1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2015 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 /* Prototypes for local functions */
66 static void signals_info (char *, int);
68 static void handle_command (char *, int);
70 static void sig_print_info (enum gdb_signal
);
72 static void sig_print_header (void);
74 static void resume_cleanups (void *);
76 static int hook_stop_stub (void *);
78 static int restore_selected_frame (void *);
80 static int follow_fork (void);
82 static int follow_fork_inferior (int follow_child
, int detach_fork
);
84 static void follow_inferior_reset_breakpoints (void);
86 static void set_schedlock_func (char *args
, int from_tty
,
87 struct cmd_list_element
*c
);
89 static int currently_stepping (struct thread_info
*tp
);
91 static void xdb_handle_command (char *args
, int from_tty
);
93 void _initialize_infrun (void);
95 void nullify_last_target_wait_ptid (void);
97 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
99 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
101 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
103 /* When set, stop the 'step' command if we enter a function which has
104 no line number information. The normal behavior is that we step
105 over such function. */
106 int step_stop_if_no_debug
= 0;
108 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
109 struct cmd_list_element
*c
, const char *value
)
111 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
114 /* In asynchronous mode, but simulating synchronous execution. */
116 int sync_execution
= 0;
118 /* proceed and normal_stop use this to notify the user when the
119 inferior stopped in a different thread than it had been running
122 static ptid_t previous_inferior_ptid
;
124 /* If set (default for legacy reasons), when following a fork, GDB
125 will detach from one of the fork branches, child or parent.
126 Exactly which branch is detached depends on 'set follow-fork-mode'
129 static int detach_fork
= 1;
131 int debug_displaced
= 0;
133 show_debug_displaced (struct ui_file
*file
, int from_tty
,
134 struct cmd_list_element
*c
, const char *value
)
136 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
139 unsigned int debug_infrun
= 0;
141 show_debug_infrun (struct ui_file
*file
, int from_tty
,
142 struct cmd_list_element
*c
, const char *value
)
144 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
148 /* Support for disabling address space randomization. */
150 int disable_randomization
= 1;
153 show_disable_randomization (struct ui_file
*file
, int from_tty
,
154 struct cmd_list_element
*c
, const char *value
)
156 if (target_supports_disable_randomization ())
157 fprintf_filtered (file
,
158 _("Disabling randomization of debuggee's "
159 "virtual address space is %s.\n"),
162 fputs_filtered (_("Disabling randomization of debuggee's "
163 "virtual address space is unsupported on\n"
164 "this platform.\n"), file
);
168 set_disable_randomization (char *args
, int from_tty
,
169 struct cmd_list_element
*c
)
171 if (!target_supports_disable_randomization ())
172 error (_("Disabling randomization of debuggee's "
173 "virtual address space is unsupported on\n"
177 /* User interface for non-stop mode. */
180 static int non_stop_1
= 0;
183 set_non_stop (char *args
, int from_tty
,
184 struct cmd_list_element
*c
)
186 if (target_has_execution
)
188 non_stop_1
= non_stop
;
189 error (_("Cannot change this setting while the inferior is running."));
192 non_stop
= non_stop_1
;
196 show_non_stop (struct ui_file
*file
, int from_tty
,
197 struct cmd_list_element
*c
, const char *value
)
199 fprintf_filtered (file
,
200 _("Controlling the inferior in non-stop mode is %s.\n"),
204 /* "Observer mode" is somewhat like a more extreme version of
205 non-stop, in which all GDB operations that might affect the
206 target's execution have been disabled. */
208 int observer_mode
= 0;
209 static int observer_mode_1
= 0;
212 set_observer_mode (char *args
, int from_tty
,
213 struct cmd_list_element
*c
)
215 if (target_has_execution
)
217 observer_mode_1
= observer_mode
;
218 error (_("Cannot change this setting while the inferior is running."));
221 observer_mode
= observer_mode_1
;
223 may_write_registers
= !observer_mode
;
224 may_write_memory
= !observer_mode
;
225 may_insert_breakpoints
= !observer_mode
;
226 may_insert_tracepoints
= !observer_mode
;
227 /* We can insert fast tracepoints in or out of observer mode,
228 but enable them if we're going into this mode. */
230 may_insert_fast_tracepoints
= 1;
231 may_stop
= !observer_mode
;
232 update_target_permissions ();
234 /* Going *into* observer mode we must force non-stop, then
235 going out we leave it that way. */
238 pagination_enabled
= 0;
239 non_stop
= non_stop_1
= 1;
243 printf_filtered (_("Observer mode is now %s.\n"),
244 (observer_mode
? "on" : "off"));
248 show_observer_mode (struct ui_file
*file
, int from_tty
,
249 struct cmd_list_element
*c
, const char *value
)
251 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
254 /* This updates the value of observer mode based on changes in
255 permissions. Note that we are deliberately ignoring the values of
256 may-write-registers and may-write-memory, since the user may have
257 reason to enable these during a session, for instance to turn on a
258 debugging-related global. */
261 update_observer_mode (void)
265 newval
= (!may_insert_breakpoints
266 && !may_insert_tracepoints
267 && may_insert_fast_tracepoints
271 /* Let the user know if things change. */
272 if (newval
!= observer_mode
)
273 printf_filtered (_("Observer mode is now %s.\n"),
274 (newval
? "on" : "off"));
276 observer_mode
= observer_mode_1
= newval
;
279 /* Tables of how to react to signals; the user sets them. */
281 static unsigned char *signal_stop
;
282 static unsigned char *signal_print
;
283 static unsigned char *signal_program
;
285 /* Table of signals that are registered with "catch signal". A
286 non-zero entry indicates that the signal is caught by some "catch
287 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
289 static unsigned char *signal_catch
;
291 /* Table of signals that the target may silently handle.
292 This is automatically determined from the flags above,
293 and simply cached here. */
294 static unsigned char *signal_pass
;
296 #define SET_SIGS(nsigs,sigs,flags) \
298 int signum = (nsigs); \
299 while (signum-- > 0) \
300 if ((sigs)[signum]) \
301 (flags)[signum] = 1; \
304 #define UNSET_SIGS(nsigs,sigs,flags) \
306 int signum = (nsigs); \
307 while (signum-- > 0) \
308 if ((sigs)[signum]) \
309 (flags)[signum] = 0; \
312 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
313 this function is to avoid exporting `signal_program'. */
316 update_signals_program_target (void)
318 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
321 /* Value to pass to target_resume() to cause all threads to resume. */
323 #define RESUME_ALL minus_one_ptid
325 /* Command list pointer for the "stop" placeholder. */
327 static struct cmd_list_element
*stop_command
;
329 /* Function inferior was in as of last step command. */
331 static struct symbol
*step_start_function
;
333 /* Nonzero if we want to give control to the user when we're notified
334 of shared library events by the dynamic linker. */
335 int stop_on_solib_events
;
337 /* Enable or disable optional shared library event breakpoints
338 as appropriate when the above flag is changed. */
341 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
343 update_solib_breakpoints ();
347 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
348 struct cmd_list_element
*c
, const char *value
)
350 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
354 /* Nonzero means expecting a trace trap
355 and should stop the inferior and return silently when it happens. */
359 /* Save register contents here when executing a "finish" command or are
360 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
361 Thus this contains the return value from the called function (assuming
362 values are returned in a register). */
364 struct regcache
*stop_registers
;
366 /* Nonzero after stop if current stack frame should be printed. */
368 static int stop_print_frame
;
370 /* This is a cached copy of the pid/waitstatus of the last event
371 returned by target_wait()/deprecated_target_wait_hook(). This
372 information is returned by get_last_target_status(). */
373 static ptid_t target_last_wait_ptid
;
374 static struct target_waitstatus target_last_waitstatus
;
376 static void context_switch (ptid_t ptid
);
378 void init_thread_stepping_state (struct thread_info
*tss
);
380 static const char follow_fork_mode_child
[] = "child";
381 static const char follow_fork_mode_parent
[] = "parent";
383 static const char *const follow_fork_mode_kind_names
[] = {
384 follow_fork_mode_child
,
385 follow_fork_mode_parent
,
389 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
391 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
392 struct cmd_list_element
*c
, const char *value
)
394 fprintf_filtered (file
,
395 _("Debugger response to a program "
396 "call of fork or vfork is \"%s\".\n"),
401 /* Handle changes to the inferior list based on the type of fork,
402 which process is being followed, and whether the other process
403 should be detached. On entry inferior_ptid must be the ptid of
404 the fork parent. At return inferior_ptid is the ptid of the
405 followed inferior. */
408 follow_fork_inferior (int follow_child
, int detach_fork
)
411 int parent_pid
, child_pid
;
413 has_vforked
= (inferior_thread ()->pending_follow
.kind
414 == TARGET_WAITKIND_VFORKED
);
415 parent_pid
= ptid_get_lwp (inferior_ptid
);
417 parent_pid
= ptid_get_pid (inferior_ptid
);
419 = ptid_get_pid (inferior_thread ()->pending_follow
.value
.related_pid
);
422 && !non_stop
/* Non-stop always resumes both branches. */
423 && (!target_is_async_p () || sync_execution
)
424 && !(follow_child
|| detach_fork
|| sched_multi
))
426 /* The parent stays blocked inside the vfork syscall until the
427 child execs or exits. If we don't let the child run, then
428 the parent stays blocked. If we're telling the parent to run
429 in the foreground, the user will not be able to ctrl-c to get
430 back the terminal, effectively hanging the debug session. */
431 fprintf_filtered (gdb_stderr
, _("\
432 Can not resume the parent process over vfork in the foreground while\n\
433 holding the child stopped. Try \"set detach-on-fork\" or \
434 \"set schedule-multiple\".\n"));
435 /* FIXME output string > 80 columns. */
441 /* Detach new forked process? */
444 struct cleanup
*old_chain
;
446 /* Before detaching from the child, remove all breakpoints
447 from it. If we forked, then this has already been taken
448 care of by infrun.c. If we vforked however, any
449 breakpoint inserted in the parent is visible in the
450 child, even those added while stopped in a vfork
451 catchpoint. This will remove the breakpoints from the
452 parent also, but they'll be reinserted below. */
455 /* Keep breakpoints list in sync. */
456 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
459 if (info_verbose
|| debug_infrun
)
461 target_terminal_ours_for_output ();
462 fprintf_filtered (gdb_stdlog
,
463 _("Detaching after %s from "
464 "child process %d.\n"),
465 has_vforked
? "vfork" : "fork",
471 struct inferior
*parent_inf
, *child_inf
;
472 struct cleanup
*old_chain
;
474 /* Add process to GDB's tables. */
475 child_inf
= add_inferior (child_pid
);
477 parent_inf
= current_inferior ();
478 child_inf
->attach_flag
= parent_inf
->attach_flag
;
479 copy_terminal_info (child_inf
, parent_inf
);
480 child_inf
->gdbarch
= parent_inf
->gdbarch
;
481 copy_inferior_target_desc_info (child_inf
, parent_inf
);
483 old_chain
= save_inferior_ptid ();
484 save_current_program_space ();
486 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
487 add_thread (inferior_ptid
);
488 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
490 /* If this is a vfork child, then the address-space is
491 shared with the parent. */
494 child_inf
->pspace
= parent_inf
->pspace
;
495 child_inf
->aspace
= parent_inf
->aspace
;
497 /* The parent will be frozen until the child is done
498 with the shared region. Keep track of the
500 child_inf
->vfork_parent
= parent_inf
;
501 child_inf
->pending_detach
= 0;
502 parent_inf
->vfork_child
= child_inf
;
503 parent_inf
->pending_detach
= 0;
507 child_inf
->aspace
= new_address_space ();
508 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
509 child_inf
->removable
= 1;
510 set_current_program_space (child_inf
->pspace
);
511 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
513 /* Let the shared library layer (e.g., solib-svr4) learn
514 about this new process, relocate the cloned exec, pull
515 in shared libraries, and install the solib event
516 breakpoint. If a "cloned-VM" event was propagated
517 better throughout the core, this wouldn't be
519 solib_create_inferior_hook (0);
522 do_cleanups (old_chain
);
527 struct inferior
*parent_inf
;
529 parent_inf
= current_inferior ();
531 /* If we detached from the child, then we have to be careful
532 to not insert breakpoints in the parent until the child
533 is done with the shared memory region. However, if we're
534 staying attached to the child, then we can and should
535 insert breakpoints, so that we can debug it. A
536 subsequent child exec or exit is enough to know when does
537 the child stops using the parent's address space. */
538 parent_inf
->waiting_for_vfork_done
= detach_fork
;
539 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
544 /* Follow the child. */
545 struct inferior
*parent_inf
, *child_inf
;
546 struct program_space
*parent_pspace
;
548 if (info_verbose
|| debug_infrun
)
550 target_terminal_ours_for_output ();
551 fprintf_filtered (gdb_stdlog
,
552 _("Attaching after process %d "
553 "%s to child process %d.\n"),
555 has_vforked
? "vfork" : "fork",
559 /* Add the new inferior first, so that the target_detach below
560 doesn't unpush the target. */
562 child_inf
= add_inferior (child_pid
);
564 parent_inf
= current_inferior ();
565 child_inf
->attach_flag
= parent_inf
->attach_flag
;
566 copy_terminal_info (child_inf
, parent_inf
);
567 child_inf
->gdbarch
= parent_inf
->gdbarch
;
568 copy_inferior_target_desc_info (child_inf
, parent_inf
);
570 parent_pspace
= parent_inf
->pspace
;
572 /* If we're vforking, we want to hold on to the parent until the
573 child exits or execs. At child exec or exit time we can
574 remove the old breakpoints from the parent and detach or
575 resume debugging it. Otherwise, detach the parent now; we'll
576 want to reuse it's program/address spaces, but we can't set
577 them to the child before removing breakpoints from the
578 parent, otherwise, the breakpoints module could decide to
579 remove breakpoints from the wrong process (since they'd be
580 assigned to the same address space). */
584 gdb_assert (child_inf
->vfork_parent
== NULL
);
585 gdb_assert (parent_inf
->vfork_child
== NULL
);
586 child_inf
->vfork_parent
= parent_inf
;
587 child_inf
->pending_detach
= 0;
588 parent_inf
->vfork_child
= child_inf
;
589 parent_inf
->pending_detach
= detach_fork
;
590 parent_inf
->waiting_for_vfork_done
= 0;
592 else if (detach_fork
)
594 if (info_verbose
|| debug_infrun
)
596 target_terminal_ours_for_output ();
597 fprintf_filtered (gdb_stdlog
,
598 _("Detaching after fork from "
599 "child process %d.\n"),
603 target_detach (NULL
, 0);
606 /* Note that the detach above makes PARENT_INF dangling. */
608 /* Add the child thread to the appropriate lists, and switch to
609 this new thread, before cloning the program space, and
610 informing the solib layer about this new process. */
612 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
613 add_thread (inferior_ptid
);
615 /* If this is a vfork child, then the address-space is shared
616 with the parent. If we detached from the parent, then we can
617 reuse the parent's program/address spaces. */
618 if (has_vforked
|| detach_fork
)
620 child_inf
->pspace
= parent_pspace
;
621 child_inf
->aspace
= child_inf
->pspace
->aspace
;
625 child_inf
->aspace
= new_address_space ();
626 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
627 child_inf
->removable
= 1;
628 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
629 set_current_program_space (child_inf
->pspace
);
630 clone_program_space (child_inf
->pspace
, parent_pspace
);
632 /* Let the shared library layer (e.g., solib-svr4) learn
633 about this new process, relocate the cloned exec, pull in
634 shared libraries, and install the solib event breakpoint.
635 If a "cloned-VM" event was propagated better throughout
636 the core, this wouldn't be required. */
637 solib_create_inferior_hook (0);
641 return target_follow_fork (follow_child
, detach_fork
);
644 /* Tell the target to follow the fork we're stopped at. Returns true
645 if the inferior should be resumed; false, if the target for some
646 reason decided it's best not to resume. */
651 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
652 int should_resume
= 1;
653 struct thread_info
*tp
;
655 /* Copy user stepping state to the new inferior thread. FIXME: the
656 followed fork child thread should have a copy of most of the
657 parent thread structure's run control related fields, not just these.
658 Initialized to avoid "may be used uninitialized" warnings from gcc. */
659 struct breakpoint
*step_resume_breakpoint
= NULL
;
660 struct breakpoint
*exception_resume_breakpoint
= NULL
;
661 CORE_ADDR step_range_start
= 0;
662 CORE_ADDR step_range_end
= 0;
663 struct frame_id step_frame_id
= { 0 };
664 struct interp
*command_interp
= NULL
;
669 struct target_waitstatus wait_status
;
671 /* Get the last target status returned by target_wait(). */
672 get_last_target_status (&wait_ptid
, &wait_status
);
674 /* If not stopped at a fork event, then there's nothing else to
676 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
677 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
680 /* Check if we switched over from WAIT_PTID, since the event was
682 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
683 && !ptid_equal (inferior_ptid
, wait_ptid
))
685 /* We did. Switch back to WAIT_PTID thread, to tell the
686 target to follow it (in either direction). We'll
687 afterwards refuse to resume, and inform the user what
689 switch_to_thread (wait_ptid
);
694 tp
= inferior_thread ();
696 /* If there were any forks/vforks that were caught and are now to be
697 followed, then do so now. */
698 switch (tp
->pending_follow
.kind
)
700 case TARGET_WAITKIND_FORKED
:
701 case TARGET_WAITKIND_VFORKED
:
703 ptid_t parent
, child
;
705 /* If the user did a next/step, etc, over a fork call,
706 preserve the stepping state in the fork child. */
707 if (follow_child
&& should_resume
)
709 step_resume_breakpoint
= clone_momentary_breakpoint
710 (tp
->control
.step_resume_breakpoint
);
711 step_range_start
= tp
->control
.step_range_start
;
712 step_range_end
= tp
->control
.step_range_end
;
713 step_frame_id
= tp
->control
.step_frame_id
;
714 exception_resume_breakpoint
715 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
716 command_interp
= tp
->control
.command_interp
;
718 /* For now, delete the parent's sr breakpoint, otherwise,
719 parent/child sr breakpoints are considered duplicates,
720 and the child version will not be installed. Remove
721 this when the breakpoints module becomes aware of
722 inferiors and address spaces. */
723 delete_step_resume_breakpoint (tp
);
724 tp
->control
.step_range_start
= 0;
725 tp
->control
.step_range_end
= 0;
726 tp
->control
.step_frame_id
= null_frame_id
;
727 delete_exception_resume_breakpoint (tp
);
728 tp
->control
.command_interp
= NULL
;
731 parent
= inferior_ptid
;
732 child
= tp
->pending_follow
.value
.related_pid
;
734 /* Set up inferior(s) as specified by the caller, and tell the
735 target to do whatever is necessary to follow either parent
737 if (follow_fork_inferior (follow_child
, detach_fork
))
739 /* Target refused to follow, or there's some other reason
740 we shouldn't resume. */
745 /* This pending follow fork event is now handled, one way
746 or another. The previous selected thread may be gone
747 from the lists by now, but if it is still around, need
748 to clear the pending follow request. */
749 tp
= find_thread_ptid (parent
);
751 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
753 /* This makes sure we don't try to apply the "Switched
754 over from WAIT_PID" logic above. */
755 nullify_last_target_wait_ptid ();
757 /* If we followed the child, switch to it... */
760 switch_to_thread (child
);
762 /* ... and preserve the stepping state, in case the
763 user was stepping over the fork call. */
766 tp
= inferior_thread ();
767 tp
->control
.step_resume_breakpoint
768 = step_resume_breakpoint
;
769 tp
->control
.step_range_start
= step_range_start
;
770 tp
->control
.step_range_end
= step_range_end
;
771 tp
->control
.step_frame_id
= step_frame_id
;
772 tp
->control
.exception_resume_breakpoint
773 = exception_resume_breakpoint
;
774 tp
->control
.command_interp
= command_interp
;
778 /* If we get here, it was because we're trying to
779 resume from a fork catchpoint, but, the user
780 has switched threads away from the thread that
781 forked. In that case, the resume command
782 issued is most likely not applicable to the
783 child, so just warn, and refuse to resume. */
784 warning (_("Not resuming: switched threads "
785 "before following fork child.\n"));
788 /* Reset breakpoints in the child as appropriate. */
789 follow_inferior_reset_breakpoints ();
792 switch_to_thread (parent
);
796 case TARGET_WAITKIND_SPURIOUS
:
797 /* Nothing to follow. */
800 internal_error (__FILE__
, __LINE__
,
801 "Unexpected pending_follow.kind %d\n",
802 tp
->pending_follow
.kind
);
806 return should_resume
;
810 follow_inferior_reset_breakpoints (void)
812 struct thread_info
*tp
= inferior_thread ();
814 /* Was there a step_resume breakpoint? (There was if the user
815 did a "next" at the fork() call.) If so, explicitly reset its
816 thread number. Cloned step_resume breakpoints are disabled on
817 creation, so enable it here now that it is associated with the
820 step_resumes are a form of bp that are made to be per-thread.
821 Since we created the step_resume bp when the parent process
822 was being debugged, and now are switching to the child process,
823 from the breakpoint package's viewpoint, that's a switch of
824 "threads". We must update the bp's notion of which thread
825 it is for, or it'll be ignored when it triggers. */
827 if (tp
->control
.step_resume_breakpoint
)
829 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
830 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
833 /* Treat exception_resume breakpoints like step_resume breakpoints. */
834 if (tp
->control
.exception_resume_breakpoint
)
836 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
837 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
840 /* Reinsert all breakpoints in the child. The user may have set
841 breakpoints after catching the fork, in which case those
842 were never set in the child, but only in the parent. This makes
843 sure the inserted breakpoints match the breakpoint list. */
845 breakpoint_re_set ();
846 insert_breakpoints ();
849 /* The child has exited or execed: resume threads of the parent the
850 user wanted to be executing. */
853 proceed_after_vfork_done (struct thread_info
*thread
,
856 int pid
= * (int *) arg
;
858 if (ptid_get_pid (thread
->ptid
) == pid
859 && is_running (thread
->ptid
)
860 && !is_executing (thread
->ptid
)
861 && !thread
->stop_requested
862 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
865 fprintf_unfiltered (gdb_stdlog
,
866 "infrun: resuming vfork parent thread %s\n",
867 target_pid_to_str (thread
->ptid
));
869 switch_to_thread (thread
->ptid
);
870 clear_proceed_status (0);
871 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
, 0);
877 /* Called whenever we notice an exec or exit event, to handle
878 detaching or resuming a vfork parent. */
881 handle_vfork_child_exec_or_exit (int exec
)
883 struct inferior
*inf
= current_inferior ();
885 if (inf
->vfork_parent
)
887 int resume_parent
= -1;
889 /* This exec or exit marks the end of the shared memory region
890 between the parent and the child. If the user wanted to
891 detach from the parent, now is the time. */
893 if (inf
->vfork_parent
->pending_detach
)
895 struct thread_info
*tp
;
896 struct cleanup
*old_chain
;
897 struct program_space
*pspace
;
898 struct address_space
*aspace
;
900 /* follow-fork child, detach-on-fork on. */
902 inf
->vfork_parent
->pending_detach
= 0;
906 /* If we're handling a child exit, then inferior_ptid
907 points at the inferior's pid, not to a thread. */
908 old_chain
= save_inferior_ptid ();
909 save_current_program_space ();
910 save_current_inferior ();
913 old_chain
= save_current_space_and_thread ();
915 /* We're letting loose of the parent. */
916 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
917 switch_to_thread (tp
->ptid
);
919 /* We're about to detach from the parent, which implicitly
920 removes breakpoints from its address space. There's a
921 catch here: we want to reuse the spaces for the child,
922 but, parent/child are still sharing the pspace at this
923 point, although the exec in reality makes the kernel give
924 the child a fresh set of new pages. The problem here is
925 that the breakpoints module being unaware of this, would
926 likely chose the child process to write to the parent
927 address space. Swapping the child temporarily away from
928 the spaces has the desired effect. Yes, this is "sort
931 pspace
= inf
->pspace
;
932 aspace
= inf
->aspace
;
936 if (debug_infrun
|| info_verbose
)
938 target_terminal_ours_for_output ();
942 fprintf_filtered (gdb_stdlog
,
943 _("Detaching vfork parent process "
944 "%d after child exec.\n"),
945 inf
->vfork_parent
->pid
);
949 fprintf_filtered (gdb_stdlog
,
950 _("Detaching vfork parent process "
951 "%d after child exit.\n"),
952 inf
->vfork_parent
->pid
);
956 target_detach (NULL
, 0);
959 inf
->pspace
= pspace
;
960 inf
->aspace
= aspace
;
962 do_cleanups (old_chain
);
966 /* We're staying attached to the parent, so, really give the
967 child a new address space. */
968 inf
->pspace
= add_program_space (maybe_new_address_space ());
969 inf
->aspace
= inf
->pspace
->aspace
;
971 set_current_program_space (inf
->pspace
);
973 resume_parent
= inf
->vfork_parent
->pid
;
975 /* Break the bonds. */
976 inf
->vfork_parent
->vfork_child
= NULL
;
980 struct cleanup
*old_chain
;
981 struct program_space
*pspace
;
983 /* If this is a vfork child exiting, then the pspace and
984 aspaces were shared with the parent. Since we're
985 reporting the process exit, we'll be mourning all that is
986 found in the address space, and switching to null_ptid,
987 preparing to start a new inferior. But, since we don't
988 want to clobber the parent's address/program spaces, we
989 go ahead and create a new one for this exiting
992 /* Switch to null_ptid, so that clone_program_space doesn't want
993 to read the selected frame of a dead process. */
994 old_chain
= save_inferior_ptid ();
995 inferior_ptid
= null_ptid
;
997 /* This inferior is dead, so avoid giving the breakpoints
998 module the option to write through to it (cloning a
999 program space resets breakpoints). */
1002 pspace
= add_program_space (maybe_new_address_space ());
1003 set_current_program_space (pspace
);
1005 inf
->symfile_flags
= SYMFILE_NO_READ
;
1006 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1007 inf
->pspace
= pspace
;
1008 inf
->aspace
= pspace
->aspace
;
1010 /* Put back inferior_ptid. We'll continue mourning this
1012 do_cleanups (old_chain
);
1014 resume_parent
= inf
->vfork_parent
->pid
;
1015 /* Break the bonds. */
1016 inf
->vfork_parent
->vfork_child
= NULL
;
1019 inf
->vfork_parent
= NULL
;
1021 gdb_assert (current_program_space
== inf
->pspace
);
1023 if (non_stop
&& resume_parent
!= -1)
1025 /* If the user wanted the parent to be running, let it go
1027 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1030 fprintf_unfiltered (gdb_stdlog
,
1031 "infrun: resuming vfork parent process %d\n",
1034 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1036 do_cleanups (old_chain
);
1041 /* Enum strings for "set|show follow-exec-mode". */
1043 static const char follow_exec_mode_new
[] = "new";
1044 static const char follow_exec_mode_same
[] = "same";
1045 static const char *const follow_exec_mode_names
[] =
1047 follow_exec_mode_new
,
1048 follow_exec_mode_same
,
1052 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1054 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1055 struct cmd_list_element
*c
, const char *value
)
1057 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1060 /* EXECD_PATHNAME is assumed to be non-NULL. */
1063 follow_exec (ptid_t ptid
, char *execd_pathname
)
1065 struct thread_info
*th
, *tmp
;
1066 struct inferior
*inf
= current_inferior ();
1067 int pid
= ptid_get_pid (ptid
);
1069 /* This is an exec event that we actually wish to pay attention to.
1070 Refresh our symbol table to the newly exec'd program, remove any
1071 momentary bp's, etc.
1073 If there are breakpoints, they aren't really inserted now,
1074 since the exec() transformed our inferior into a fresh set
1077 We want to preserve symbolic breakpoints on the list, since
1078 we have hopes that they can be reset after the new a.out's
1079 symbol table is read.
1081 However, any "raw" breakpoints must be removed from the list
1082 (e.g., the solib bp's), since their address is probably invalid
1085 And, we DON'T want to call delete_breakpoints() here, since
1086 that may write the bp's "shadow contents" (the instruction
1087 value that was overwritten witha TRAP instruction). Since
1088 we now have a new a.out, those shadow contents aren't valid. */
1090 mark_breakpoints_out ();
1092 /* The target reports the exec event to the main thread, even if
1093 some other thread does the exec, and even if the main thread was
1094 stopped or already gone. We may still have non-leader threads of
1095 the process on our list. E.g., on targets that don't have thread
1096 exit events (like remote); or on native Linux in non-stop mode if
1097 there were only two threads in the inferior and the non-leader
1098 one is the one that execs (and nothing forces an update of the
1099 thread list up to here). When debugging remotely, it's best to
1100 avoid extra traffic, when possible, so avoid syncing the thread
1101 list with the target, and instead go ahead and delete all threads
1102 of the process but one that reported the event. Note this must
1103 be done before calling update_breakpoints_after_exec, as
1104 otherwise clearing the threads' resources would reference stale
1105 thread breakpoints -- it may have been one of these threads that
1106 stepped across the exec. We could just clear their stepping
1107 states, but as long as we're iterating, might as well delete
1108 them. Deleting them now rather than at the next user-visible
1109 stop provides a nicer sequence of events for user and MI
1111 ALL_NON_EXITED_THREADS_SAFE (th
, tmp
)
1112 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1113 delete_thread (th
->ptid
);
1115 /* We also need to clear any left over stale state for the
1116 leader/event thread. E.g., if there was any step-resume
1117 breakpoint or similar, it's gone now. We cannot truly
1118 step-to-next statement through an exec(). */
1119 th
= inferior_thread ();
1120 th
->control
.step_resume_breakpoint
= NULL
;
1121 th
->control
.exception_resume_breakpoint
= NULL
;
1122 th
->control
.single_step_breakpoints
= NULL
;
1123 th
->control
.step_range_start
= 0;
1124 th
->control
.step_range_end
= 0;
1126 /* The user may have had the main thread held stopped in the
1127 previous image (e.g., schedlock on, or non-stop). Release
1129 th
->stop_requested
= 0;
1131 update_breakpoints_after_exec ();
1133 /* What is this a.out's name? */
1134 printf_unfiltered (_("%s is executing new program: %s\n"),
1135 target_pid_to_str (inferior_ptid
),
1138 /* We've followed the inferior through an exec. Therefore, the
1139 inferior has essentially been killed & reborn. */
1141 gdb_flush (gdb_stdout
);
1143 breakpoint_init_inferior (inf_execd
);
1145 if (gdb_sysroot
&& *gdb_sysroot
)
1147 char *name
= alloca (strlen (gdb_sysroot
)
1148 + strlen (execd_pathname
)
1151 strcpy (name
, gdb_sysroot
);
1152 strcat (name
, execd_pathname
);
1153 execd_pathname
= name
;
1156 /* Reset the shared library package. This ensures that we get a
1157 shlib event when the child reaches "_start", at which point the
1158 dld will have had a chance to initialize the child. */
1159 /* Also, loading a symbol file below may trigger symbol lookups, and
1160 we don't want those to be satisfied by the libraries of the
1161 previous incarnation of this process. */
1162 no_shared_libraries (NULL
, 0);
1164 if (follow_exec_mode_string
== follow_exec_mode_new
)
1166 struct program_space
*pspace
;
1168 /* The user wants to keep the old inferior and program spaces
1169 around. Create a new fresh one, and switch to it. */
1171 inf
= add_inferior (current_inferior ()->pid
);
1172 pspace
= add_program_space (maybe_new_address_space ());
1173 inf
->pspace
= pspace
;
1174 inf
->aspace
= pspace
->aspace
;
1176 exit_inferior_num_silent (current_inferior ()->num
);
1178 set_current_inferior (inf
);
1179 set_current_program_space (pspace
);
1183 /* The old description may no longer be fit for the new image.
1184 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1185 old description; we'll read a new one below. No need to do
1186 this on "follow-exec-mode new", as the old inferior stays
1187 around (its description is later cleared/refetched on
1189 target_clear_description ();
1192 gdb_assert (current_program_space
== inf
->pspace
);
1194 /* That a.out is now the one to use. */
1195 exec_file_attach (execd_pathname
, 0);
1197 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1198 (Position Independent Executable) main symbol file will get applied by
1199 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1200 the breakpoints with the zero displacement. */
1202 symbol_file_add (execd_pathname
,
1204 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1207 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1208 set_initial_language ();
1210 /* If the target can specify a description, read it. Must do this
1211 after flipping to the new executable (because the target supplied
1212 description must be compatible with the executable's
1213 architecture, and the old executable may e.g., be 32-bit, while
1214 the new one 64-bit), and before anything involving memory or
1216 target_find_description ();
1218 solib_create_inferior_hook (0);
1220 jit_inferior_created_hook ();
1222 breakpoint_re_set ();
1224 /* Reinsert all breakpoints. (Those which were symbolic have
1225 been reset to the proper address in the new a.out, thanks
1226 to symbol_file_command...). */
1227 insert_breakpoints ();
1229 /* The next resume of this inferior should bring it to the shlib
1230 startup breakpoints. (If the user had also set bp's on
1231 "main" from the old (parent) process, then they'll auto-
1232 matically get reset there in the new process.). */
1235 /* Info about an instruction that is being stepped over. */
1237 struct step_over_info
1239 /* If we're stepping past a breakpoint, this is the address space
1240 and address of the instruction the breakpoint is set at. We'll
1241 skip inserting all breakpoints here. Valid iff ASPACE is
1243 struct address_space
*aspace
;
1246 /* The instruction being stepped over triggers a nonsteppable
1247 watchpoint. If true, we'll skip inserting watchpoints. */
1248 int nonsteppable_watchpoint_p
;
1251 /* The step-over info of the location that is being stepped over.
1253 Note that with async/breakpoint always-inserted mode, a user might
1254 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1255 being stepped over. As setting a new breakpoint inserts all
1256 breakpoints, we need to make sure the breakpoint being stepped over
1257 isn't inserted then. We do that by only clearing the step-over
1258 info when the step-over is actually finished (or aborted).
1260 Presently GDB can only step over one breakpoint at any given time.
1261 Given threads that can't run code in the same address space as the
1262 breakpoint's can't really miss the breakpoint, GDB could be taught
1263 to step-over at most one breakpoint per address space (so this info
1264 could move to the address space object if/when GDB is extended).
1265 The set of breakpoints being stepped over will normally be much
1266 smaller than the set of all breakpoints, so a flag in the
1267 breakpoint location structure would be wasteful. A separate list
1268 also saves complexity and run-time, as otherwise we'd have to go
1269 through all breakpoint locations clearing their flag whenever we
1270 start a new sequence. Similar considerations weigh against storing
1271 this info in the thread object. Plus, not all step overs actually
1272 have breakpoint locations -- e.g., stepping past a single-step
1273 breakpoint, or stepping to complete a non-continuable
1275 static struct step_over_info step_over_info
;
1277 /* Record the address of the breakpoint/instruction we're currently
1281 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1282 int nonsteppable_watchpoint_p
)
1284 step_over_info
.aspace
= aspace
;
1285 step_over_info
.address
= address
;
1286 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1289 /* Called when we're not longer stepping over a breakpoint / an
1290 instruction, so all breakpoints are free to be (re)inserted. */
1293 clear_step_over_info (void)
1295 step_over_info
.aspace
= NULL
;
1296 step_over_info
.address
= 0;
1297 step_over_info
.nonsteppable_watchpoint_p
= 0;
1303 stepping_past_instruction_at (struct address_space
*aspace
,
1306 return (step_over_info
.aspace
!= NULL
1307 && breakpoint_address_match (aspace
, address
,
1308 step_over_info
.aspace
,
1309 step_over_info
.address
));
1315 stepping_past_nonsteppable_watchpoint (void)
1317 return step_over_info
.nonsteppable_watchpoint_p
;
1320 /* Returns true if step-over info is valid. */
1323 step_over_info_valid_p (void)
1325 return (step_over_info
.aspace
!= NULL
1326 || stepping_past_nonsteppable_watchpoint ());
1330 /* Displaced stepping. */
1332 /* In non-stop debugging mode, we must take special care to manage
1333 breakpoints properly; in particular, the traditional strategy for
1334 stepping a thread past a breakpoint it has hit is unsuitable.
1335 'Displaced stepping' is a tactic for stepping one thread past a
1336 breakpoint it has hit while ensuring that other threads running
1337 concurrently will hit the breakpoint as they should.
1339 The traditional way to step a thread T off a breakpoint in a
1340 multi-threaded program in all-stop mode is as follows:
1342 a0) Initially, all threads are stopped, and breakpoints are not
1344 a1) We single-step T, leaving breakpoints uninserted.
1345 a2) We insert breakpoints, and resume all threads.
1347 In non-stop debugging, however, this strategy is unsuitable: we
1348 don't want to have to stop all threads in the system in order to
1349 continue or step T past a breakpoint. Instead, we use displaced
1352 n0) Initially, T is stopped, other threads are running, and
1353 breakpoints are inserted.
1354 n1) We copy the instruction "under" the breakpoint to a separate
1355 location, outside the main code stream, making any adjustments
1356 to the instruction, register, and memory state as directed by
1358 n2) We single-step T over the instruction at its new location.
1359 n3) We adjust the resulting register and memory state as directed
1360 by T's architecture. This includes resetting T's PC to point
1361 back into the main instruction stream.
1364 This approach depends on the following gdbarch methods:
1366 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1367 indicate where to copy the instruction, and how much space must
1368 be reserved there. We use these in step n1.
1370 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1371 address, and makes any necessary adjustments to the instruction,
1372 register contents, and memory. We use this in step n1.
1374 - gdbarch_displaced_step_fixup adjusts registers and memory after
1375 we have successfuly single-stepped the instruction, to yield the
1376 same effect the instruction would have had if we had executed it
1377 at its original address. We use this in step n3.
1379 - gdbarch_displaced_step_free_closure provides cleanup.
1381 The gdbarch_displaced_step_copy_insn and
1382 gdbarch_displaced_step_fixup functions must be written so that
1383 copying an instruction with gdbarch_displaced_step_copy_insn,
1384 single-stepping across the copied instruction, and then applying
1385 gdbarch_displaced_insn_fixup should have the same effects on the
1386 thread's memory and registers as stepping the instruction in place
1387 would have. Exactly which responsibilities fall to the copy and
1388 which fall to the fixup is up to the author of those functions.
1390 See the comments in gdbarch.sh for details.
1392 Note that displaced stepping and software single-step cannot
1393 currently be used in combination, although with some care I think
1394 they could be made to. Software single-step works by placing
1395 breakpoints on all possible subsequent instructions; if the
1396 displaced instruction is a PC-relative jump, those breakpoints
1397 could fall in very strange places --- on pages that aren't
1398 executable, or at addresses that are not proper instruction
1399 boundaries. (We do generally let other threads run while we wait
1400 to hit the software single-step breakpoint, and they might
1401 encounter such a corrupted instruction.) One way to work around
1402 this would be to have gdbarch_displaced_step_copy_insn fully
1403 simulate the effect of PC-relative instructions (and return NULL)
1404 on architectures that use software single-stepping.
1406 In non-stop mode, we can have independent and simultaneous step
1407 requests, so more than one thread may need to simultaneously step
1408 over a breakpoint. The current implementation assumes there is
1409 only one scratch space per process. In this case, we have to
1410 serialize access to the scratch space. If thread A wants to step
1411 over a breakpoint, but we are currently waiting for some other
1412 thread to complete a displaced step, we leave thread A stopped and
1413 place it in the displaced_step_request_queue. Whenever a displaced
1414 step finishes, we pick the next thread in the queue and start a new
1415 displaced step operation on it. See displaced_step_prepare and
1416 displaced_step_fixup for details. */
1418 struct displaced_step_request
1421 struct displaced_step_request
*next
;
1424 /* Per-inferior displaced stepping state. */
1425 struct displaced_step_inferior_state
1427 /* Pointer to next in linked list. */
1428 struct displaced_step_inferior_state
*next
;
1430 /* The process this displaced step state refers to. */
1433 /* A queue of pending displaced stepping requests. One entry per
1434 thread that needs to do a displaced step. */
1435 struct displaced_step_request
*step_request_queue
;
1437 /* If this is not null_ptid, this is the thread carrying out a
1438 displaced single-step in process PID. This thread's state will
1439 require fixing up once it has completed its step. */
1442 /* The architecture the thread had when we stepped it. */
1443 struct gdbarch
*step_gdbarch
;
1445 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1446 for post-step cleanup. */
1447 struct displaced_step_closure
*step_closure
;
1449 /* The address of the original instruction, and the copy we
1451 CORE_ADDR step_original
, step_copy
;
1453 /* Saved contents of copy area. */
1454 gdb_byte
*step_saved_copy
;
1457 /* The list of states of processes involved in displaced stepping
1459 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1461 /* Get the displaced stepping state of process PID. */
1463 static struct displaced_step_inferior_state
*
1464 get_displaced_stepping_state (int pid
)
1466 struct displaced_step_inferior_state
*state
;
1468 for (state
= displaced_step_inferior_states
;
1470 state
= state
->next
)
1471 if (state
->pid
== pid
)
1477 /* Add a new displaced stepping state for process PID to the displaced
1478 stepping state list, or return a pointer to an already existing
1479 entry, if it already exists. Never returns NULL. */
1481 static struct displaced_step_inferior_state
*
1482 add_displaced_stepping_state (int pid
)
1484 struct displaced_step_inferior_state
*state
;
1486 for (state
= displaced_step_inferior_states
;
1488 state
= state
->next
)
1489 if (state
->pid
== pid
)
1492 state
= xcalloc (1, sizeof (*state
));
1494 state
->next
= displaced_step_inferior_states
;
1495 displaced_step_inferior_states
= state
;
1500 /* If inferior is in displaced stepping, and ADDR equals to starting address
1501 of copy area, return corresponding displaced_step_closure. Otherwise,
1504 struct displaced_step_closure
*
1505 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1507 struct displaced_step_inferior_state
*displaced
1508 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1510 /* If checking the mode of displaced instruction in copy area. */
1511 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1512 && (displaced
->step_copy
== addr
))
1513 return displaced
->step_closure
;
1518 /* Remove the displaced stepping state of process PID. */
1521 remove_displaced_stepping_state (int pid
)
1523 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1525 gdb_assert (pid
!= 0);
1527 it
= displaced_step_inferior_states
;
1528 prev_next_p
= &displaced_step_inferior_states
;
1533 *prev_next_p
= it
->next
;
1538 prev_next_p
= &it
->next
;
1544 infrun_inferior_exit (struct inferior
*inf
)
1546 remove_displaced_stepping_state (inf
->pid
);
1549 /* If ON, and the architecture supports it, GDB will use displaced
1550 stepping to step over breakpoints. If OFF, or if the architecture
1551 doesn't support it, GDB will instead use the traditional
1552 hold-and-step approach. If AUTO (which is the default), GDB will
1553 decide which technique to use to step over breakpoints depending on
1554 which of all-stop or non-stop mode is active --- displaced stepping
1555 in non-stop mode; hold-and-step in all-stop mode. */
1557 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1560 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1561 struct cmd_list_element
*c
,
1564 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1565 fprintf_filtered (file
,
1566 _("Debugger's willingness to use displaced stepping "
1567 "to step over breakpoints is %s (currently %s).\n"),
1568 value
, non_stop
? "on" : "off");
1570 fprintf_filtered (file
,
1571 _("Debugger's willingness to use displaced stepping "
1572 "to step over breakpoints is %s.\n"), value
);
1575 /* Return non-zero if displaced stepping can/should be used to step
1576 over breakpoints. */
1579 use_displaced_stepping (struct gdbarch
*gdbarch
)
1581 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
&& non_stop
)
1582 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1583 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1584 && find_record_target () == NULL
);
1587 /* Clean out any stray displaced stepping state. */
1589 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1591 /* Indicate that there is no cleanup pending. */
1592 displaced
->step_ptid
= null_ptid
;
1594 if (displaced
->step_closure
)
1596 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1597 displaced
->step_closure
);
1598 displaced
->step_closure
= NULL
;
1603 displaced_step_clear_cleanup (void *arg
)
1605 struct displaced_step_inferior_state
*state
= arg
;
1607 displaced_step_clear (state
);
1610 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1612 displaced_step_dump_bytes (struct ui_file
*file
,
1613 const gdb_byte
*buf
,
1618 for (i
= 0; i
< len
; i
++)
1619 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1620 fputs_unfiltered ("\n", file
);
1623 /* Prepare to single-step, using displaced stepping.
1625 Note that we cannot use displaced stepping when we have a signal to
1626 deliver. If we have a signal to deliver and an instruction to step
1627 over, then after the step, there will be no indication from the
1628 target whether the thread entered a signal handler or ignored the
1629 signal and stepped over the instruction successfully --- both cases
1630 result in a simple SIGTRAP. In the first case we mustn't do a
1631 fixup, and in the second case we must --- but we can't tell which.
1632 Comments in the code for 'random signals' in handle_inferior_event
1633 explain how we handle this case instead.
1635 Returns 1 if preparing was successful -- this thread is going to be
1636 stepped now; or 0 if displaced stepping this thread got queued. */
1638 displaced_step_prepare (ptid_t ptid
)
1640 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1641 struct thread_info
*tp
= find_thread_ptid (ptid
);
1642 struct regcache
*regcache
= get_thread_regcache (ptid
);
1643 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1644 CORE_ADDR original
, copy
;
1646 struct displaced_step_closure
*closure
;
1647 struct displaced_step_inferior_state
*displaced
;
1650 /* We should never reach this function if the architecture does not
1651 support displaced stepping. */
1652 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1654 /* Disable range stepping while executing in the scratch pad. We
1655 want a single-step even if executing the displaced instruction in
1656 the scratch buffer lands within the stepping range (e.g., a
1658 tp
->control
.may_range_step
= 0;
1660 /* We have to displaced step one thread at a time, as we only have
1661 access to a single scratch space per inferior. */
1663 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1665 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1667 /* Already waiting for a displaced step to finish. Defer this
1668 request and place in queue. */
1669 struct displaced_step_request
*req
, *new_req
;
1671 if (debug_displaced
)
1672 fprintf_unfiltered (gdb_stdlog
,
1673 "displaced: defering step of %s\n",
1674 target_pid_to_str (ptid
));
1676 new_req
= xmalloc (sizeof (*new_req
));
1677 new_req
->ptid
= ptid
;
1678 new_req
->next
= NULL
;
1680 if (displaced
->step_request_queue
)
1682 for (req
= displaced
->step_request_queue
;
1686 req
->next
= new_req
;
1689 displaced
->step_request_queue
= new_req
;
1695 if (debug_displaced
)
1696 fprintf_unfiltered (gdb_stdlog
,
1697 "displaced: stepping %s now\n",
1698 target_pid_to_str (ptid
));
1701 displaced_step_clear (displaced
);
1703 old_cleanups
= save_inferior_ptid ();
1704 inferior_ptid
= ptid
;
1706 original
= regcache_read_pc (regcache
);
1708 copy
= gdbarch_displaced_step_location (gdbarch
);
1709 len
= gdbarch_max_insn_length (gdbarch
);
1711 /* Save the original contents of the copy area. */
1712 displaced
->step_saved_copy
= xmalloc (len
);
1713 ignore_cleanups
= make_cleanup (free_current_contents
,
1714 &displaced
->step_saved_copy
);
1715 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1717 throw_error (MEMORY_ERROR
,
1718 _("Error accessing memory address %s (%s) for "
1719 "displaced-stepping scratch space."),
1720 paddress (gdbarch
, copy
), safe_strerror (status
));
1721 if (debug_displaced
)
1723 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1724 paddress (gdbarch
, copy
));
1725 displaced_step_dump_bytes (gdb_stdlog
,
1726 displaced
->step_saved_copy
,
1730 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1731 original
, copy
, regcache
);
1733 /* We don't support the fully-simulated case at present. */
1734 gdb_assert (closure
);
1736 /* Save the information we need to fix things up if the step
1738 displaced
->step_ptid
= ptid
;
1739 displaced
->step_gdbarch
= gdbarch
;
1740 displaced
->step_closure
= closure
;
1741 displaced
->step_original
= original
;
1742 displaced
->step_copy
= copy
;
1744 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1746 /* Resume execution at the copy. */
1747 regcache_write_pc (regcache
, copy
);
1749 discard_cleanups (ignore_cleanups
);
1751 do_cleanups (old_cleanups
);
1753 if (debug_displaced
)
1754 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1755 paddress (gdbarch
, copy
));
1761 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1762 const gdb_byte
*myaddr
, int len
)
1764 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1766 inferior_ptid
= ptid
;
1767 write_memory (memaddr
, myaddr
, len
);
1768 do_cleanups (ptid_cleanup
);
1771 /* Restore the contents of the copy area for thread PTID. */
1774 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1777 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1779 write_memory_ptid (ptid
, displaced
->step_copy
,
1780 displaced
->step_saved_copy
, len
);
1781 if (debug_displaced
)
1782 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1783 target_pid_to_str (ptid
),
1784 paddress (displaced
->step_gdbarch
,
1785 displaced
->step_copy
));
1789 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1791 struct cleanup
*old_cleanups
;
1792 struct displaced_step_inferior_state
*displaced
1793 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1795 /* Was any thread of this process doing a displaced step? */
1796 if (displaced
== NULL
)
1799 /* Was this event for the pid we displaced? */
1800 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1801 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1804 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1806 displaced_step_restore (displaced
, displaced
->step_ptid
);
1808 /* Did the instruction complete successfully? */
1809 if (signal
== GDB_SIGNAL_TRAP
)
1811 /* Fixup may need to read memory/registers. Switch to the
1812 thread that we're fixing up. */
1813 switch_to_thread (event_ptid
);
1815 /* Fix up the resulting state. */
1816 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1817 displaced
->step_closure
,
1818 displaced
->step_original
,
1819 displaced
->step_copy
,
1820 get_thread_regcache (displaced
->step_ptid
));
1824 /* Since the instruction didn't complete, all we can do is
1826 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1827 CORE_ADDR pc
= regcache_read_pc (regcache
);
1829 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1830 regcache_write_pc (regcache
, pc
);
1833 do_cleanups (old_cleanups
);
1835 displaced
->step_ptid
= null_ptid
;
1837 /* Are there any pending displaced stepping requests? If so, run
1838 one now. Leave the state object around, since we're likely to
1839 need it again soon. */
1840 while (displaced
->step_request_queue
)
1842 struct displaced_step_request
*head
;
1844 struct regcache
*regcache
;
1845 struct gdbarch
*gdbarch
;
1846 CORE_ADDR actual_pc
;
1847 struct address_space
*aspace
;
1849 head
= displaced
->step_request_queue
;
1851 displaced
->step_request_queue
= head
->next
;
1854 context_switch (ptid
);
1856 regcache
= get_thread_regcache (ptid
);
1857 actual_pc
= regcache_read_pc (regcache
);
1858 aspace
= get_regcache_aspace (regcache
);
1860 if (breakpoint_here_p (aspace
, actual_pc
))
1862 if (debug_displaced
)
1863 fprintf_unfiltered (gdb_stdlog
,
1864 "displaced: stepping queued %s now\n",
1865 target_pid_to_str (ptid
));
1867 displaced_step_prepare (ptid
);
1869 gdbarch
= get_regcache_arch (regcache
);
1871 if (debug_displaced
)
1873 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1876 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1877 paddress (gdbarch
, actual_pc
));
1878 read_memory (actual_pc
, buf
, sizeof (buf
));
1879 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1882 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1883 displaced
->step_closure
))
1884 target_resume (ptid
, 1, GDB_SIGNAL_0
);
1886 target_resume (ptid
, 0, GDB_SIGNAL_0
);
1888 /* Done, we're stepping a thread. */
1894 struct thread_info
*tp
= inferior_thread ();
1896 /* The breakpoint we were sitting under has since been
1898 tp
->control
.trap_expected
= 0;
1900 /* Go back to what we were trying to do. */
1901 step
= currently_stepping (tp
);
1903 if (debug_displaced
)
1904 fprintf_unfiltered (gdb_stdlog
,
1905 "displaced: breakpoint is gone: %s, step(%d)\n",
1906 target_pid_to_str (tp
->ptid
), step
);
1908 target_resume (ptid
, step
, GDB_SIGNAL_0
);
1909 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1911 /* This request was discarded. See if there's any other
1912 thread waiting for its turn. */
1917 /* Update global variables holding ptids to hold NEW_PTID if they were
1918 holding OLD_PTID. */
1920 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1922 struct displaced_step_request
*it
;
1923 struct displaced_step_inferior_state
*displaced
;
1925 if (ptid_equal (inferior_ptid
, old_ptid
))
1926 inferior_ptid
= new_ptid
;
1928 for (displaced
= displaced_step_inferior_states
;
1930 displaced
= displaced
->next
)
1932 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1933 displaced
->step_ptid
= new_ptid
;
1935 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1936 if (ptid_equal (it
->ptid
, old_ptid
))
1937 it
->ptid
= new_ptid
;
1944 /* Things to clean up if we QUIT out of resume (). */
1946 resume_cleanups (void *ignore
)
1948 if (!ptid_equal (inferior_ptid
, null_ptid
))
1949 delete_single_step_breakpoints (inferior_thread ());
1954 static const char schedlock_off
[] = "off";
1955 static const char schedlock_on
[] = "on";
1956 static const char schedlock_step
[] = "step";
1957 static const char *const scheduler_enums
[] = {
1963 static const char *scheduler_mode
= schedlock_off
;
1965 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1966 struct cmd_list_element
*c
, const char *value
)
1968 fprintf_filtered (file
,
1969 _("Mode for locking scheduler "
1970 "during execution is \"%s\".\n"),
1975 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1977 if (!target_can_lock_scheduler
)
1979 scheduler_mode
= schedlock_off
;
1980 error (_("Target '%s' cannot support this command."), target_shortname
);
1984 /* True if execution commands resume all threads of all processes by
1985 default; otherwise, resume only threads of the current inferior
1987 int sched_multi
= 0;
1989 /* Try to setup for software single stepping over the specified location.
1990 Return 1 if target_resume() should use hardware single step.
1992 GDBARCH the current gdbarch.
1993 PC the location to step over. */
1996 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2000 if (execution_direction
== EXEC_FORWARD
2001 && gdbarch_software_single_step_p (gdbarch
)
2002 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
2010 user_visible_resume_ptid (int step
)
2012 /* By default, resume all threads of all processes. */
2013 ptid_t resume_ptid
= RESUME_ALL
;
2015 /* Maybe resume only all threads of the current process. */
2016 if (!sched_multi
&& target_supports_multi_process ())
2018 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2021 /* Maybe resume a single thread after all. */
2024 /* With non-stop mode on, threads are always handled
2026 resume_ptid
= inferior_ptid
;
2028 else if ((scheduler_mode
== schedlock_on
)
2029 || (scheduler_mode
== schedlock_step
&& step
))
2031 /* User-settable 'scheduler' mode requires solo thread resume. */
2032 resume_ptid
= inferior_ptid
;
2035 /* We may actually resume fewer threads at first, e.g., if a thread
2036 is stopped at a breakpoint that needs stepping-off, but that
2037 should not be visible to the user/frontend, and neither should
2038 the frontend/user be allowed to proceed any of the threads that
2039 happen to be stopped for internal run control handling, if a
2040 previous command wanted them resumed. */
2044 /* Resume the inferior, but allow a QUIT. This is useful if the user
2045 wants to interrupt some lengthy single-stepping operation
2046 (for child processes, the SIGINT goes to the inferior, and so
2047 we get a SIGINT random_signal, but for remote debugging and perhaps
2048 other targets, that's not true).
2050 STEP nonzero if we should step (zero to continue instead).
2051 SIG is the signal to give the inferior (zero for none). */
2053 resume (int step
, enum gdb_signal sig
)
2055 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2056 struct regcache
*regcache
= get_current_regcache ();
2057 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2058 struct thread_info
*tp
= inferior_thread ();
2059 CORE_ADDR pc
= regcache_read_pc (regcache
);
2060 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2062 /* From here on, this represents the caller's step vs continue
2063 request, while STEP represents what we'll actually request the
2064 target to do. STEP can decay from a step to a continue, if e.g.,
2065 we need to implement single-stepping with breakpoints (software
2066 single-step). When deciding whether "set scheduler-locking step"
2067 applies, it's the callers intention that counts. */
2068 const int entry_step
= step
;
2070 tp
->stepped_breakpoint
= 0;
2074 if (current_inferior ()->waiting_for_vfork_done
)
2076 /* Don't try to single-step a vfork parent that is waiting for
2077 the child to get out of the shared memory region (by exec'ing
2078 or exiting). This is particularly important on software
2079 single-step archs, as the child process would trip on the
2080 software single step breakpoint inserted for the parent
2081 process. Since the parent will not actually execute any
2082 instruction until the child is out of the shared region (such
2083 are vfork's semantics), it is safe to simply continue it.
2084 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2085 the parent, and tell it to `keep_going', which automatically
2086 re-sets it stepping. */
2088 fprintf_unfiltered (gdb_stdlog
,
2089 "infrun: resume : clear step\n");
2094 fprintf_unfiltered (gdb_stdlog
,
2095 "infrun: resume (step=%d, signal=%s), "
2096 "trap_expected=%d, current thread [%s] at %s\n",
2097 step
, gdb_signal_to_symbol_string (sig
),
2098 tp
->control
.trap_expected
,
2099 target_pid_to_str (inferior_ptid
),
2100 paddress (gdbarch
, pc
));
2102 /* Normally, by the time we reach `resume', the breakpoints are either
2103 removed or inserted, as appropriate. The exception is if we're sitting
2104 at a permanent breakpoint; we need to step over it, but permanent
2105 breakpoints can't be removed. So we have to test for it here. */
2106 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2108 if (sig
!= GDB_SIGNAL_0
)
2110 /* We have a signal to pass to the inferior. The resume
2111 may, or may not take us to the signal handler. If this
2112 is a step, we'll need to stop in the signal handler, if
2113 there's one, (if the target supports stepping into
2114 handlers), or in the next mainline instruction, if
2115 there's no handler. If this is a continue, we need to be
2116 sure to run the handler with all breakpoints inserted.
2117 In all cases, set a breakpoint at the current address
2118 (where the handler returns to), and once that breakpoint
2119 is hit, resume skipping the permanent breakpoint. If
2120 that breakpoint isn't hit, then we've stepped into the
2121 signal handler (or hit some other event). We'll delete
2122 the step-resume breakpoint then. */
2125 fprintf_unfiltered (gdb_stdlog
,
2126 "infrun: resume: skipping permanent breakpoint, "
2127 "deliver signal first\n");
2129 clear_step_over_info ();
2130 tp
->control
.trap_expected
= 0;
2132 if (tp
->control
.step_resume_breakpoint
== NULL
)
2134 /* Set a "high-priority" step-resume, as we don't want
2135 user breakpoints at PC to trigger (again) when this
2137 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2138 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2140 tp
->step_after_step_resume_breakpoint
= step
;
2143 insert_breakpoints ();
2147 /* There's no signal to pass, we can go ahead and skip the
2148 permanent breakpoint manually. */
2150 fprintf_unfiltered (gdb_stdlog
,
2151 "infrun: resume: skipping permanent breakpoint\n");
2152 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2153 /* Update pc to reflect the new address from which we will
2154 execute instructions. */
2155 pc
= regcache_read_pc (regcache
);
2159 /* We've already advanced the PC, so the stepping part
2160 is done. Now we need to arrange for a trap to be
2161 reported to handle_inferior_event. Set a breakpoint
2162 at the current PC, and run to it. Don't update
2163 prev_pc, because if we end in
2164 switch_back_to_stepping, we want the "expected thread
2165 advanced also" branch to be taken. IOW, we don't
2166 want this thread to step further from PC
2168 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2169 insert_breakpoints ();
2171 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2172 /* We're continuing with all breakpoints inserted. It's
2173 safe to let the target bypass signals. */
2174 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2175 /* ... and safe to let other threads run, according to
2177 resume_ptid
= user_visible_resume_ptid (entry_step
);
2178 target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2179 discard_cleanups (old_cleanups
);
2185 /* If we have a breakpoint to step over, make sure to do a single
2186 step only. Same if we have software watchpoints. */
2187 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2188 tp
->control
.may_range_step
= 0;
2190 /* If enabled, step over breakpoints by executing a copy of the
2191 instruction at a different address.
2193 We can't use displaced stepping when we have a signal to deliver;
2194 the comments for displaced_step_prepare explain why. The
2195 comments in the handle_inferior event for dealing with 'random
2196 signals' explain what we do instead.
2198 We can't use displaced stepping when we are waiting for vfork_done
2199 event, displaced stepping breaks the vfork child similarly as single
2200 step software breakpoint. */
2201 if (use_displaced_stepping (gdbarch
)
2202 && tp
->control
.trap_expected
2203 && sig
== GDB_SIGNAL_0
2204 && !current_inferior ()->waiting_for_vfork_done
)
2206 struct displaced_step_inferior_state
*displaced
;
2208 if (!displaced_step_prepare (inferior_ptid
))
2210 /* Got placed in displaced stepping queue. Will be resumed
2211 later when all the currently queued displaced stepping
2212 requests finish. The thread is not executing at this
2213 point, and the call to set_executing will be made later.
2214 But we need to call set_running here, since from the
2215 user/frontend's point of view, threads were set running.
2216 Unless we're calling an inferior function, as in that
2217 case we pretend the inferior doesn't run at all. */
2218 if (!tp
->control
.in_infcall
)
2219 set_running (user_visible_resume_ptid (entry_step
), 1);
2220 discard_cleanups (old_cleanups
);
2224 /* Update pc to reflect the new address from which we will execute
2225 instructions due to displaced stepping. */
2226 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2228 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2229 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2230 displaced
->step_closure
);
2233 /* Do we need to do it the hard way, w/temp breakpoints? */
2235 step
= maybe_software_singlestep (gdbarch
, pc
);
2237 /* Currently, our software single-step implementation leads to different
2238 results than hardware single-stepping in one situation: when stepping
2239 into delivering a signal which has an associated signal handler,
2240 hardware single-step will stop at the first instruction of the handler,
2241 while software single-step will simply skip execution of the handler.
2243 For now, this difference in behavior is accepted since there is no
2244 easy way to actually implement single-stepping into a signal handler
2245 without kernel support.
2247 However, there is one scenario where this difference leads to follow-on
2248 problems: if we're stepping off a breakpoint by removing all breakpoints
2249 and then single-stepping. In this case, the software single-step
2250 behavior means that even if there is a *breakpoint* in the signal
2251 handler, GDB still would not stop.
2253 Fortunately, we can at least fix this particular issue. We detect
2254 here the case where we are about to deliver a signal while software
2255 single-stepping with breakpoints removed. In this situation, we
2256 revert the decisions to remove all breakpoints and insert single-
2257 step breakpoints, and instead we install a step-resume breakpoint
2258 at the current address, deliver the signal without stepping, and
2259 once we arrive back at the step-resume breakpoint, actually step
2260 over the breakpoint we originally wanted to step over. */
2261 if (thread_has_single_step_breakpoints_set (tp
)
2262 && sig
!= GDB_SIGNAL_0
2263 && step_over_info_valid_p ())
2265 /* If we have nested signals or a pending signal is delivered
2266 immediately after a handler returns, might might already have
2267 a step-resume breakpoint set on the earlier handler. We cannot
2268 set another step-resume breakpoint; just continue on until the
2269 original breakpoint is hit. */
2270 if (tp
->control
.step_resume_breakpoint
== NULL
)
2272 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2273 tp
->step_after_step_resume_breakpoint
= 1;
2276 delete_single_step_breakpoints (tp
);
2278 clear_step_over_info ();
2279 tp
->control
.trap_expected
= 0;
2281 insert_breakpoints ();
2284 /* If STEP is set, it's a request to use hardware stepping
2285 facilities. But in that case, we should never
2286 use singlestep breakpoint. */
2287 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2289 /* Decide the set of threads to ask the target to resume. Start
2290 by assuming everything will be resumed, than narrow the set
2291 by applying increasingly restricting conditions. */
2292 resume_ptid
= user_visible_resume_ptid (entry_step
);
2294 /* Even if RESUME_PTID is a wildcard, and we end up resuming less
2295 (e.g., we might need to step over a breakpoint), from the
2296 user/frontend's point of view, all threads in RESUME_PTID are now
2297 running. Unless we're calling an inferior function, as in that
2298 case pretend we inferior doesn't run at all. */
2299 if (!tp
->control
.in_infcall
)
2300 set_running (resume_ptid
, 1);
2302 /* Maybe resume a single thread after all. */
2303 if ((step
|| thread_has_single_step_breakpoints_set (tp
))
2304 && tp
->control
.trap_expected
)
2306 /* We're allowing a thread to run past a breakpoint it has
2307 hit, by single-stepping the thread with the breakpoint
2308 removed. In which case, we need to single-step only this
2309 thread, and keep others stopped, as they can miss this
2310 breakpoint if allowed to run. */
2311 resume_ptid
= inferior_ptid
;
2314 if (execution_direction
!= EXEC_REVERSE
2315 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2317 /* The only case we currently need to step a breakpoint
2318 instruction is when we have a signal to deliver. See
2319 handle_signal_stop where we handle random signals that could
2320 take out us out of the stepping range. Normally, in that
2321 case we end up continuing (instead of stepping) over the
2322 signal handler with a breakpoint at PC, but there are cases
2323 where we should _always_ single-step, even if we have a
2324 step-resume breakpoint, like when a software watchpoint is
2325 set. Assuming single-stepping and delivering a signal at the
2326 same time would takes us to the signal handler, then we could
2327 have removed the breakpoint at PC to step over it. However,
2328 some hardware step targets (like e.g., Mac OS) can't step
2329 into signal handlers, and for those, we need to leave the
2330 breakpoint at PC inserted, as otherwise if the handler
2331 recurses and executes PC again, it'll miss the breakpoint.
2332 So we leave the breakpoint inserted anyway, but we need to
2333 record that we tried to step a breakpoint instruction, so
2334 that adjust_pc_after_break doesn't end up confused. */
2335 gdb_assert (sig
!= GDB_SIGNAL_0
);
2337 tp
->stepped_breakpoint
= 1;
2339 /* Most targets can step a breakpoint instruction, thus
2340 executing it normally. But if this one cannot, just
2341 continue and we will hit it anyway. */
2342 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2347 && use_displaced_stepping (gdbarch
)
2348 && tp
->control
.trap_expected
)
2350 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
2351 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2352 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2355 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2356 paddress (resume_gdbarch
, actual_pc
));
2357 read_memory (actual_pc
, buf
, sizeof (buf
));
2358 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2361 if (tp
->control
.may_range_step
)
2363 /* If we're resuming a thread with the PC out of the step
2364 range, then we're doing some nested/finer run control
2365 operation, like stepping the thread out of the dynamic
2366 linker or the displaced stepping scratch pad. We
2367 shouldn't have allowed a range step then. */
2368 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2371 /* Install inferior's terminal modes. */
2372 target_terminal_inferior ();
2374 /* Avoid confusing the next resume, if the next stop/resume
2375 happens to apply to another thread. */
2376 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2378 /* Advise target which signals may be handled silently. If we have
2379 removed breakpoints because we are stepping over one (in any
2380 thread), we need to receive all signals to avoid accidentally
2381 skipping a breakpoint during execution of a signal handler. */
2382 if (step_over_info_valid_p ())
2383 target_pass_signals (0, NULL
);
2385 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2387 target_resume (resume_ptid
, step
, sig
);
2389 discard_cleanups (old_cleanups
);
2394 /* Clear out all variables saying what to do when inferior is continued.
2395 First do this, then set the ones you want, then call `proceed'. */
2398 clear_proceed_status_thread (struct thread_info
*tp
)
2401 fprintf_unfiltered (gdb_stdlog
,
2402 "infrun: clear_proceed_status_thread (%s)\n",
2403 target_pid_to_str (tp
->ptid
));
2405 /* If this signal should not be seen by program, give it zero.
2406 Used for debugging signals. */
2407 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2408 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2410 tp
->control
.trap_expected
= 0;
2411 tp
->control
.step_range_start
= 0;
2412 tp
->control
.step_range_end
= 0;
2413 tp
->control
.may_range_step
= 0;
2414 tp
->control
.step_frame_id
= null_frame_id
;
2415 tp
->control
.step_stack_frame_id
= null_frame_id
;
2416 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2417 tp
->stop_requested
= 0;
2419 tp
->control
.stop_step
= 0;
2421 tp
->control
.proceed_to_finish
= 0;
2423 tp
->control
.command_interp
= NULL
;
2425 /* Discard any remaining commands or status from previous stop. */
2426 bpstat_clear (&tp
->control
.stop_bpstat
);
2430 clear_proceed_status (int step
)
2434 struct thread_info
*tp
;
2437 resume_ptid
= user_visible_resume_ptid (step
);
2439 /* In all-stop mode, delete the per-thread status of all threads
2440 we're about to resume, implicitly and explicitly. */
2441 ALL_NON_EXITED_THREADS (tp
)
2443 if (!ptid_match (tp
->ptid
, resume_ptid
))
2445 clear_proceed_status_thread (tp
);
2449 if (!ptid_equal (inferior_ptid
, null_ptid
))
2451 struct inferior
*inferior
;
2455 /* If in non-stop mode, only delete the per-thread status of
2456 the current thread. */
2457 clear_proceed_status_thread (inferior_thread ());
2460 inferior
= current_inferior ();
2461 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2464 stop_after_trap
= 0;
2466 clear_step_over_info ();
2468 observer_notify_about_to_proceed ();
2472 regcache_xfree (stop_registers
);
2473 stop_registers
= NULL
;
2477 /* Returns true if TP is still stopped at a breakpoint that needs
2478 stepping-over in order to make progress. If the breakpoint is gone
2479 meanwhile, we can skip the whole step-over dance. */
2482 thread_still_needs_step_over (struct thread_info
*tp
)
2484 if (tp
->stepping_over_breakpoint
)
2486 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2488 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2489 regcache_read_pc (regcache
))
2490 == ordinary_breakpoint_here
)
2493 tp
->stepping_over_breakpoint
= 0;
2499 /* Returns true if scheduler locking applies. STEP indicates whether
2500 we're about to do a step/next-like command to a thread. */
2503 schedlock_applies (int step
)
2505 return (scheduler_mode
== schedlock_on
2506 || (scheduler_mode
== schedlock_step
2510 /* Look a thread other than EXCEPT that has previously reported a
2511 breakpoint event, and thus needs a step-over in order to make
2512 progress. Returns NULL is none is found. STEP indicates whether
2513 we're about to step the current thread, in order to decide whether
2514 "set scheduler-locking step" applies. */
2516 static struct thread_info
*
2517 find_thread_needs_step_over (int step
, struct thread_info
*except
)
2519 struct thread_info
*tp
, *current
;
2521 /* With non-stop mode on, threads are always handled individually. */
2522 gdb_assert (! non_stop
);
2524 current
= inferior_thread ();
2526 /* If scheduler locking applies, we can avoid iterating over all
2528 if (schedlock_applies (step
))
2530 if (except
!= current
2531 && thread_still_needs_step_over (current
))
2537 ALL_NON_EXITED_THREADS (tp
)
2539 /* Ignore the EXCEPT thread. */
2542 /* Ignore threads of processes we're not resuming. */
2544 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
2547 if (thread_still_needs_step_over (tp
))
2554 /* Basic routine for continuing the program in various fashions.
2556 ADDR is the address to resume at, or -1 for resume where stopped.
2557 SIGGNAL is the signal to give it, or 0 for none,
2558 or -1 for act according to how it stopped.
2559 STEP is nonzero if should trap after one instruction.
2560 -1 means return after that and print nothing.
2561 You should probably set various step_... variables
2562 before calling here, if you are stepping.
2564 You should call clear_proceed_status before calling proceed. */
2567 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
, int step
)
2569 struct regcache
*regcache
;
2570 struct gdbarch
*gdbarch
;
2571 struct thread_info
*tp
;
2573 struct address_space
*aspace
;
2575 /* If we're stopped at a fork/vfork, follow the branch set by the
2576 "set follow-fork-mode" command; otherwise, we'll just proceed
2577 resuming the current thread. */
2578 if (!follow_fork ())
2580 /* The target for some reason decided not to resume. */
2582 if (target_can_async_p ())
2583 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2587 /* We'll update this if & when we switch to a new thread. */
2588 previous_inferior_ptid
= inferior_ptid
;
2590 regcache
= get_current_regcache ();
2591 gdbarch
= get_regcache_arch (regcache
);
2592 aspace
= get_regcache_aspace (regcache
);
2593 pc
= regcache_read_pc (regcache
);
2594 tp
= inferior_thread ();
2597 step_start_function
= find_pc_function (pc
);
2599 stop_after_trap
= 1;
2601 /* Fill in with reasonable starting values. */
2602 init_thread_stepping_state (tp
);
2604 if (addr
== (CORE_ADDR
) -1)
2607 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
2608 && execution_direction
!= EXEC_REVERSE
)
2609 /* There is a breakpoint at the address we will resume at,
2610 step one instruction before inserting breakpoints so that
2611 we do not stop right away (and report a second hit at this
2614 Note, we don't do this in reverse, because we won't
2615 actually be executing the breakpoint insn anyway.
2616 We'll be (un-)executing the previous instruction. */
2617 tp
->stepping_over_breakpoint
= 1;
2618 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2619 && gdbarch_single_step_through_delay (gdbarch
,
2620 get_current_frame ()))
2621 /* We stepped onto an instruction that needs to be stepped
2622 again before re-inserting the breakpoint, do so. */
2623 tp
->stepping_over_breakpoint
= 1;
2627 regcache_write_pc (regcache
, addr
);
2630 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2631 tp
->suspend
.stop_signal
= siggnal
;
2633 /* Record the interpreter that issued the execution command that
2634 caused this thread to resume. If the top level interpreter is
2635 MI/async, and the execution command was a CLI command
2636 (next/step/etc.), we'll want to print stop event output to the MI
2637 console channel (the stepped-to line, etc.), as if the user
2638 entered the execution command on a real GDB console. */
2639 inferior_thread ()->control
.command_interp
= command_interp ();
2642 fprintf_unfiltered (gdb_stdlog
,
2643 "infrun: proceed (addr=%s, signal=%s, step=%d)\n",
2644 paddress (gdbarch
, addr
),
2645 gdb_signal_to_symbol_string (siggnal
), step
);
2648 /* In non-stop, each thread is handled individually. The context
2649 must already be set to the right thread here. */
2653 struct thread_info
*step_over
;
2655 /* In a multi-threaded task we may select another thread and
2656 then continue or step.
2658 But if the old thread was stopped at a breakpoint, it will
2659 immediately cause another breakpoint stop without any
2660 execution (i.e. it will report a breakpoint hit incorrectly).
2661 So we must step over it first.
2663 Look for a thread other than the current (TP) that reported a
2664 breakpoint hit and hasn't been resumed yet since. */
2665 step_over
= find_thread_needs_step_over (step
, tp
);
2666 if (step_over
!= NULL
)
2669 fprintf_unfiltered (gdb_stdlog
,
2670 "infrun: need to step-over [%s] first\n",
2671 target_pid_to_str (step_over
->ptid
));
2673 /* Store the prev_pc for the stepping thread too, needed by
2674 switch_back_to_stepping thread. */
2675 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2676 switch_to_thread (step_over
->ptid
);
2681 /* If we need to step over a breakpoint, and we're not using
2682 displaced stepping to do so, insert all breakpoints (watchpoints,
2683 etc.) but the one we're stepping over, step one instruction, and
2684 then re-insert the breakpoint when that step is finished. */
2685 if (tp
->stepping_over_breakpoint
&& !use_displaced_stepping (gdbarch
))
2687 struct regcache
*regcache
= get_current_regcache ();
2689 set_step_over_info (get_regcache_aspace (regcache
),
2690 regcache_read_pc (regcache
), 0);
2693 clear_step_over_info ();
2695 insert_breakpoints ();
2697 tp
->control
.trap_expected
= tp
->stepping_over_breakpoint
;
2699 annotate_starting ();
2701 /* Make sure that output from GDB appears before output from the
2703 gdb_flush (gdb_stdout
);
2705 /* Refresh prev_pc value just prior to resuming. This used to be
2706 done in stop_waiting, however, setting prev_pc there did not handle
2707 scenarios such as inferior function calls or returning from
2708 a function via the return command. In those cases, the prev_pc
2709 value was not set properly for subsequent commands. The prev_pc value
2710 is used to initialize the starting line number in the ecs. With an
2711 invalid value, the gdb next command ends up stopping at the position
2712 represented by the next line table entry past our start position.
2713 On platforms that generate one line table entry per line, this
2714 is not a problem. However, on the ia64, the compiler generates
2715 extraneous line table entries that do not increase the line number.
2716 When we issue the gdb next command on the ia64 after an inferior call
2717 or a return command, we often end up a few instructions forward, still
2718 within the original line we started.
2720 An attempt was made to refresh the prev_pc at the same time the
2721 execution_control_state is initialized (for instance, just before
2722 waiting for an inferior event). But this approach did not work
2723 because of platforms that use ptrace, where the pc register cannot
2724 be read unless the inferior is stopped. At that point, we are not
2725 guaranteed the inferior is stopped and so the regcache_read_pc() call
2726 can fail. Setting the prev_pc value here ensures the value is updated
2727 correctly when the inferior is stopped. */
2728 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2730 /* Resume inferior. */
2731 resume (tp
->control
.trap_expected
|| step
|| bpstat_should_step (),
2732 tp
->suspend
.stop_signal
);
2734 /* Wait for it to stop (if not standalone)
2735 and in any case decode why it stopped, and act accordingly. */
2736 /* Do this only if we are not using the event loop, or if the target
2737 does not support asynchronous execution. */
2738 if (!target_can_async_p ())
2740 wait_for_inferior ();
2746 /* Start remote-debugging of a machine over a serial link. */
2749 start_remote (int from_tty
)
2751 struct inferior
*inferior
;
2753 inferior
= current_inferior ();
2754 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2756 /* Always go on waiting for the target, regardless of the mode. */
2757 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2758 indicate to wait_for_inferior that a target should timeout if
2759 nothing is returned (instead of just blocking). Because of this,
2760 targets expecting an immediate response need to, internally, set
2761 things up so that the target_wait() is forced to eventually
2763 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2764 differentiate to its caller what the state of the target is after
2765 the initial open has been performed. Here we're assuming that
2766 the target has stopped. It should be possible to eventually have
2767 target_open() return to the caller an indication that the target
2768 is currently running and GDB state should be set to the same as
2769 for an async run. */
2770 wait_for_inferior ();
2772 /* Now that the inferior has stopped, do any bookkeeping like
2773 loading shared libraries. We want to do this before normal_stop,
2774 so that the displayed frame is up to date. */
2775 post_create_inferior (¤t_target
, from_tty
);
2780 /* Initialize static vars when a new inferior begins. */
2783 init_wait_for_inferior (void)
2785 /* These are meaningless until the first time through wait_for_inferior. */
2787 breakpoint_init_inferior (inf_starting
);
2789 clear_proceed_status (0);
2791 target_last_wait_ptid
= minus_one_ptid
;
2793 previous_inferior_ptid
= inferior_ptid
;
2795 /* Discard any skipped inlined frames. */
2796 clear_inline_frame_state (minus_one_ptid
);
2800 /* Data to be passed around while handling an event. This data is
2801 discarded between events. */
2802 struct execution_control_state
2805 /* The thread that got the event, if this was a thread event; NULL
2807 struct thread_info
*event_thread
;
2809 struct target_waitstatus ws
;
2810 int stop_func_filled_in
;
2811 CORE_ADDR stop_func_start
;
2812 CORE_ADDR stop_func_end
;
2813 const char *stop_func_name
;
2816 /* True if the event thread hit the single-step breakpoint of
2817 another thread. Thus the event doesn't cause a stop, the thread
2818 needs to be single-stepped past the single-step breakpoint before
2819 we can switch back to the original stepping thread. */
2820 int hit_singlestep_breakpoint
;
2823 static void handle_inferior_event (struct execution_control_state
*ecs
);
2825 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2826 struct execution_control_state
*ecs
);
2827 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2828 struct execution_control_state
*ecs
);
2829 static void handle_signal_stop (struct execution_control_state
*ecs
);
2830 static void check_exception_resume (struct execution_control_state
*,
2831 struct frame_info
*);
2833 static void end_stepping_range (struct execution_control_state
*ecs
);
2834 static void stop_waiting (struct execution_control_state
*ecs
);
2835 static void prepare_to_wait (struct execution_control_state
*ecs
);
2836 static void keep_going (struct execution_control_state
*ecs
);
2837 static void process_event_stop_test (struct execution_control_state
*ecs
);
2838 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
2840 /* Callback for iterate over threads. If the thread is stopped, but
2841 the user/frontend doesn't know about that yet, go through
2842 normal_stop, as if the thread had just stopped now. ARG points at
2843 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2844 ptid_is_pid(PTID) is true, applies to all threads of the process
2845 pointed at by PTID. Otherwise, apply only to the thread pointed by
2849 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2851 ptid_t ptid
= * (ptid_t
*) arg
;
2853 if ((ptid_equal (info
->ptid
, ptid
)
2854 || ptid_equal (minus_one_ptid
, ptid
)
2855 || (ptid_is_pid (ptid
)
2856 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2857 && is_running (info
->ptid
)
2858 && !is_executing (info
->ptid
))
2860 struct cleanup
*old_chain
;
2861 struct execution_control_state ecss
;
2862 struct execution_control_state
*ecs
= &ecss
;
2864 memset (ecs
, 0, sizeof (*ecs
));
2866 old_chain
= make_cleanup_restore_current_thread ();
2868 overlay_cache_invalid
= 1;
2869 /* Flush target cache before starting to handle each event.
2870 Target was running and cache could be stale. This is just a
2871 heuristic. Running threads may modify target memory, but we
2872 don't get any event. */
2873 target_dcache_invalidate ();
2875 /* Go through handle_inferior_event/normal_stop, so we always
2876 have consistent output as if the stop event had been
2878 ecs
->ptid
= info
->ptid
;
2879 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2880 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2881 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2883 handle_inferior_event (ecs
);
2885 if (!ecs
->wait_some_more
)
2887 struct thread_info
*tp
;
2891 /* Finish off the continuations. */
2892 tp
= inferior_thread ();
2893 do_all_intermediate_continuations_thread (tp
, 1);
2894 do_all_continuations_thread (tp
, 1);
2897 do_cleanups (old_chain
);
2903 /* This function is attached as a "thread_stop_requested" observer.
2904 Cleanup local state that assumed the PTID was to be resumed, and
2905 report the stop to the frontend. */
2908 infrun_thread_stop_requested (ptid_t ptid
)
2910 struct displaced_step_inferior_state
*displaced
;
2912 /* PTID was requested to stop. Remove it from the displaced
2913 stepping queue, so we don't try to resume it automatically. */
2915 for (displaced
= displaced_step_inferior_states
;
2917 displaced
= displaced
->next
)
2919 struct displaced_step_request
*it
, **prev_next_p
;
2921 it
= displaced
->step_request_queue
;
2922 prev_next_p
= &displaced
->step_request_queue
;
2925 if (ptid_match (it
->ptid
, ptid
))
2927 *prev_next_p
= it
->next
;
2933 prev_next_p
= &it
->next
;
2940 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2944 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2946 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2947 nullify_last_target_wait_ptid ();
2950 /* Delete the step resume, single-step and longjmp/exception resume
2951 breakpoints of TP. */
2954 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
2956 delete_step_resume_breakpoint (tp
);
2957 delete_exception_resume_breakpoint (tp
);
2958 delete_single_step_breakpoints (tp
);
2961 /* If the target still has execution, call FUNC for each thread that
2962 just stopped. In all-stop, that's all the non-exited threads; in
2963 non-stop, that's the current thread, only. */
2965 typedef void (*for_each_just_stopped_thread_callback_func
)
2966 (struct thread_info
*tp
);
2969 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
2971 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
2976 /* If in non-stop mode, only the current thread stopped. */
2977 func (inferior_thread ());
2981 struct thread_info
*tp
;
2983 /* In all-stop mode, all threads have stopped. */
2984 ALL_NON_EXITED_THREADS (tp
)
2991 /* Delete the step resume and longjmp/exception resume breakpoints of
2992 the threads that just stopped. */
2995 delete_just_stopped_threads_infrun_breakpoints (void)
2997 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3000 /* Delete the single-step breakpoints of the threads that just
3004 delete_just_stopped_threads_single_step_breakpoints (void)
3006 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3009 /* A cleanup wrapper. */
3012 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3014 delete_just_stopped_threads_infrun_breakpoints ();
3017 /* Pretty print the results of target_wait, for debugging purposes. */
3020 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3021 const struct target_waitstatus
*ws
)
3023 char *status_string
= target_waitstatus_to_string (ws
);
3024 struct ui_file
*tmp_stream
= mem_fileopen ();
3027 /* The text is split over several lines because it was getting too long.
3028 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3029 output as a unit; we want only one timestamp printed if debug_timestamp
3032 fprintf_unfiltered (tmp_stream
,
3033 "infrun: target_wait (%d", ptid_get_pid (waiton_ptid
));
3034 if (ptid_get_pid (waiton_ptid
) != -1)
3035 fprintf_unfiltered (tmp_stream
,
3036 " [%s]", target_pid_to_str (waiton_ptid
));
3037 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3038 fprintf_unfiltered (tmp_stream
,
3039 "infrun: %d [%s],\n",
3040 ptid_get_pid (result_ptid
),
3041 target_pid_to_str (result_ptid
));
3042 fprintf_unfiltered (tmp_stream
,
3046 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3048 /* This uses %s in part to handle %'s in the text, but also to avoid
3049 a gcc error: the format attribute requires a string literal. */
3050 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3052 xfree (status_string
);
3054 ui_file_delete (tmp_stream
);
3057 /* Prepare and stabilize the inferior for detaching it. E.g.,
3058 detaching while a thread is displaced stepping is a recipe for
3059 crashing it, as nothing would readjust the PC out of the scratch
3063 prepare_for_detach (void)
3065 struct inferior
*inf
= current_inferior ();
3066 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3067 struct cleanup
*old_chain_1
;
3068 struct displaced_step_inferior_state
*displaced
;
3070 displaced
= get_displaced_stepping_state (inf
->pid
);
3072 /* Is any thread of this process displaced stepping? If not,
3073 there's nothing else to do. */
3074 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3078 fprintf_unfiltered (gdb_stdlog
,
3079 "displaced-stepping in-process while detaching");
3081 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3084 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3086 struct cleanup
*old_chain_2
;
3087 struct execution_control_state ecss
;
3088 struct execution_control_state
*ecs
;
3091 memset (ecs
, 0, sizeof (*ecs
));
3093 overlay_cache_invalid
= 1;
3094 /* Flush target cache before starting to handle each event.
3095 Target was running and cache could be stale. This is just a
3096 heuristic. Running threads may modify target memory, but we
3097 don't get any event. */
3098 target_dcache_invalidate ();
3100 if (deprecated_target_wait_hook
)
3101 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
3103 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
3106 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3108 /* If an error happens while handling the event, propagate GDB's
3109 knowledge of the executing state to the frontend/user running
3111 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3114 /* Now figure out what to do with the result of the result. */
3115 handle_inferior_event (ecs
);
3117 /* No error, don't finish the state yet. */
3118 discard_cleanups (old_chain_2
);
3120 /* Breakpoints and watchpoints are not installed on the target
3121 at this point, and signals are passed directly to the
3122 inferior, so this must mean the process is gone. */
3123 if (!ecs
->wait_some_more
)
3125 discard_cleanups (old_chain_1
);
3126 error (_("Program exited while detaching"));
3130 discard_cleanups (old_chain_1
);
3133 /* Wait for control to return from inferior to debugger.
3135 If inferior gets a signal, we may decide to start it up again
3136 instead of returning. That is why there is a loop in this function.
3137 When this function actually returns it means the inferior
3138 should be left stopped and GDB should read more commands. */
3141 wait_for_inferior (void)
3143 struct cleanup
*old_cleanups
;
3147 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3150 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3155 struct execution_control_state ecss
;
3156 struct execution_control_state
*ecs
= &ecss
;
3157 struct cleanup
*old_chain
;
3158 ptid_t waiton_ptid
= minus_one_ptid
;
3160 memset (ecs
, 0, sizeof (*ecs
));
3162 overlay_cache_invalid
= 1;
3164 /* Flush target cache before starting to handle each event.
3165 Target was running and cache could be stale. This is just a
3166 heuristic. Running threads may modify target memory, but we
3167 don't get any event. */
3168 target_dcache_invalidate ();
3170 if (deprecated_target_wait_hook
)
3171 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
3173 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
3176 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3178 /* If an error happens while handling the event, propagate GDB's
3179 knowledge of the executing state to the frontend/user running
3181 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3183 /* Now figure out what to do with the result of the result. */
3184 handle_inferior_event (ecs
);
3186 /* No error, don't finish the state yet. */
3187 discard_cleanups (old_chain
);
3189 if (!ecs
->wait_some_more
)
3193 do_cleanups (old_cleanups
);
3196 /* Cleanup that reinstalls the readline callback handler, if the
3197 target is running in the background. If while handling the target
3198 event something triggered a secondary prompt, like e.g., a
3199 pagination prompt, we'll have removed the callback handler (see
3200 gdb_readline_wrapper_line). Need to do this as we go back to the
3201 event loop, ready to process further input. Note this has no
3202 effect if the handler hasn't actually been removed, because calling
3203 rl_callback_handler_install resets the line buffer, thus losing
3207 reinstall_readline_callback_handler_cleanup (void *arg
)
3209 if (!interpreter_async
)
3211 /* We're not going back to the top level event loop yet. Don't
3212 install the readline callback, as it'd prep the terminal,
3213 readline-style (raw, noecho) (e.g., --batch). We'll install
3214 it the next time the prompt is displayed, when we're ready
3219 if (async_command_editing_p
&& !sync_execution
)
3220 gdb_rl_callback_handler_reinstall ();
3223 /* Asynchronous version of wait_for_inferior. It is called by the
3224 event loop whenever a change of state is detected on the file
3225 descriptor corresponding to the target. It can be called more than
3226 once to complete a single execution command. In such cases we need
3227 to keep the state in a global variable ECSS. If it is the last time
3228 that this function is called for a single execution command, then
3229 report to the user that the inferior has stopped, and do the
3230 necessary cleanups. */
3233 fetch_inferior_event (void *client_data
)
3235 struct execution_control_state ecss
;
3236 struct execution_control_state
*ecs
= &ecss
;
3237 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3238 struct cleanup
*ts_old_chain
;
3239 int was_sync
= sync_execution
;
3241 ptid_t waiton_ptid
= minus_one_ptid
;
3243 memset (ecs
, 0, sizeof (*ecs
));
3245 /* End up with readline processing input, if necessary. */
3246 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3248 /* We're handling a live event, so make sure we're doing live
3249 debugging. If we're looking at traceframes while the target is
3250 running, we're going to need to get back to that mode after
3251 handling the event. */
3254 make_cleanup_restore_current_traceframe ();
3255 set_current_traceframe (-1);
3259 /* In non-stop mode, the user/frontend should not notice a thread
3260 switch due to internal events. Make sure we reverse to the
3261 user selected thread and frame after handling the event and
3262 running any breakpoint commands. */
3263 make_cleanup_restore_current_thread ();
3265 overlay_cache_invalid
= 1;
3266 /* Flush target cache before starting to handle each event. Target
3267 was running and cache could be stale. This is just a heuristic.
3268 Running threads may modify target memory, but we don't get any
3270 target_dcache_invalidate ();
3272 make_cleanup_restore_integer (&execution_direction
);
3273 execution_direction
= target_execution_direction ();
3275 if (deprecated_target_wait_hook
)
3277 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3279 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3282 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3284 /* If an error happens while handling the event, propagate GDB's
3285 knowledge of the executing state to the frontend/user running
3288 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3290 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3292 /* Get executed before make_cleanup_restore_current_thread above to apply
3293 still for the thread which has thrown the exception. */
3294 make_bpstat_clear_actions_cleanup ();
3296 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3298 /* Now figure out what to do with the result of the result. */
3299 handle_inferior_event (ecs
);
3301 if (!ecs
->wait_some_more
)
3303 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3305 delete_just_stopped_threads_infrun_breakpoints ();
3307 /* We may not find an inferior if this was a process exit. */
3308 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3311 if (target_has_execution
3312 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
3313 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3314 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3315 && ecs
->event_thread
->step_multi
3316 && ecs
->event_thread
->control
.stop_step
)
3317 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
3320 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3325 /* No error, don't finish the thread states yet. */
3326 discard_cleanups (ts_old_chain
);
3328 /* Revert thread and frame. */
3329 do_cleanups (old_chain
);
3331 /* If the inferior was in sync execution mode, and now isn't,
3332 restore the prompt (a synchronous execution command has finished,
3333 and we're ready for input). */
3334 if (interpreter_async
&& was_sync
&& !sync_execution
)
3335 observer_notify_sync_execution_done ();
3339 && exec_done_display_p
3340 && (ptid_equal (inferior_ptid
, null_ptid
)
3341 || !is_running (inferior_ptid
)))
3342 printf_unfiltered (_("completed.\n"));
3345 /* Record the frame and location we're currently stepping through. */
3347 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3349 struct thread_info
*tp
= inferior_thread ();
3351 tp
->control
.step_frame_id
= get_frame_id (frame
);
3352 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3354 tp
->current_symtab
= sal
.symtab
;
3355 tp
->current_line
= sal
.line
;
3358 /* Clear context switchable stepping state. */
3361 init_thread_stepping_state (struct thread_info
*tss
)
3363 tss
->stepped_breakpoint
= 0;
3364 tss
->stepping_over_breakpoint
= 0;
3365 tss
->stepping_over_watchpoint
= 0;
3366 tss
->step_after_step_resume_breakpoint
= 0;
3369 /* Set the cached copy of the last ptid/waitstatus. */
3372 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3374 target_last_wait_ptid
= ptid
;
3375 target_last_waitstatus
= status
;
3378 /* Return the cached copy of the last pid/waitstatus returned by
3379 target_wait()/deprecated_target_wait_hook(). The data is actually
3380 cached by handle_inferior_event(), which gets called immediately
3381 after target_wait()/deprecated_target_wait_hook(). */
3384 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3386 *ptidp
= target_last_wait_ptid
;
3387 *status
= target_last_waitstatus
;
3391 nullify_last_target_wait_ptid (void)
3393 target_last_wait_ptid
= minus_one_ptid
;
3396 /* Switch thread contexts. */
3399 context_switch (ptid_t ptid
)
3401 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
3403 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3404 target_pid_to_str (inferior_ptid
));
3405 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3406 target_pid_to_str (ptid
));
3409 switch_to_thread (ptid
);
3413 adjust_pc_after_break (struct execution_control_state
*ecs
)
3415 struct regcache
*regcache
;
3416 struct gdbarch
*gdbarch
;
3417 struct address_space
*aspace
;
3418 CORE_ADDR breakpoint_pc
, decr_pc
;
3420 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3421 we aren't, just return.
3423 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3424 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3425 implemented by software breakpoints should be handled through the normal
3428 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3429 different signals (SIGILL or SIGEMT for instance), but it is less
3430 clear where the PC is pointing afterwards. It may not match
3431 gdbarch_decr_pc_after_break. I don't know any specific target that
3432 generates these signals at breakpoints (the code has been in GDB since at
3433 least 1992) so I can not guess how to handle them here.
3435 In earlier versions of GDB, a target with
3436 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3437 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3438 target with both of these set in GDB history, and it seems unlikely to be
3439 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3441 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
3444 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
3447 /* In reverse execution, when a breakpoint is hit, the instruction
3448 under it has already been de-executed. The reported PC always
3449 points at the breakpoint address, so adjusting it further would
3450 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3453 B1 0x08000000 : INSN1
3454 B2 0x08000001 : INSN2
3456 PC -> 0x08000003 : INSN4
3458 Say you're stopped at 0x08000003 as above. Reverse continuing
3459 from that point should hit B2 as below. Reading the PC when the
3460 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3461 been de-executed already.
3463 B1 0x08000000 : INSN1
3464 B2 PC -> 0x08000001 : INSN2
3468 We can't apply the same logic as for forward execution, because
3469 we would wrongly adjust the PC to 0x08000000, since there's a
3470 breakpoint at PC - 1. We'd then report a hit on B1, although
3471 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3473 if (execution_direction
== EXEC_REVERSE
)
3476 /* If this target does not decrement the PC after breakpoints, then
3477 we have nothing to do. */
3478 regcache
= get_thread_regcache (ecs
->ptid
);
3479 gdbarch
= get_regcache_arch (regcache
);
3481 decr_pc
= target_decr_pc_after_break (gdbarch
);
3485 aspace
= get_regcache_aspace (regcache
);
3487 /* Find the location where (if we've hit a breakpoint) the
3488 breakpoint would be. */
3489 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3491 /* Check whether there actually is a software breakpoint inserted at
3494 If in non-stop mode, a race condition is possible where we've
3495 removed a breakpoint, but stop events for that breakpoint were
3496 already queued and arrive later. To suppress those spurious
3497 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3498 and retire them after a number of stop events are reported. */
3499 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3500 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3502 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
3504 if (record_full_is_used ())
3505 record_full_gdb_operation_disable_set ();
3507 /* When using hardware single-step, a SIGTRAP is reported for both
3508 a completed single-step and a software breakpoint. Need to
3509 differentiate between the two, as the latter needs adjusting
3510 but the former does not.
3512 The SIGTRAP can be due to a completed hardware single-step only if
3513 - we didn't insert software single-step breakpoints
3514 - this thread is currently being stepped
3516 If any of these events did not occur, we must have stopped due
3517 to hitting a software breakpoint, and have to back up to the
3520 As a special case, we could have hardware single-stepped a
3521 software breakpoint. In this case (prev_pc == breakpoint_pc),
3522 we also need to back up to the breakpoint address. */
3524 if (thread_has_single_step_breakpoints_set (ecs
->event_thread
)
3525 || !currently_stepping (ecs
->event_thread
)
3526 || (ecs
->event_thread
->stepped_breakpoint
3527 && ecs
->event_thread
->prev_pc
== breakpoint_pc
))
3528 regcache_write_pc (regcache
, breakpoint_pc
);
3530 do_cleanups (old_cleanups
);
3535 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3537 for (frame
= get_prev_frame (frame
);
3539 frame
= get_prev_frame (frame
))
3541 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3543 if (get_frame_type (frame
) != INLINE_FRAME
)
3550 /* Auxiliary function that handles syscall entry/return events.
3551 It returns 1 if the inferior should keep going (and GDB
3552 should ignore the event), or 0 if the event deserves to be
3556 handle_syscall_event (struct execution_control_state
*ecs
)
3558 struct regcache
*regcache
;
3561 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3562 context_switch (ecs
->ptid
);
3564 regcache
= get_thread_regcache (ecs
->ptid
);
3565 syscall_number
= ecs
->ws
.value
.syscall_number
;
3566 stop_pc
= regcache_read_pc (regcache
);
3568 if (catch_syscall_enabled () > 0
3569 && catching_syscall_number (syscall_number
) > 0)
3572 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3575 ecs
->event_thread
->control
.stop_bpstat
3576 = bpstat_stop_status (get_regcache_aspace (regcache
),
3577 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3579 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3581 /* Catchpoint hit. */
3586 /* If no catchpoint triggered for this, then keep going. */
3591 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3594 fill_in_stop_func (struct gdbarch
*gdbarch
,
3595 struct execution_control_state
*ecs
)
3597 if (!ecs
->stop_func_filled_in
)
3599 /* Don't care about return value; stop_func_start and stop_func_name
3600 will both be 0 if it doesn't work. */
3601 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3602 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3603 ecs
->stop_func_start
3604 += gdbarch_deprecated_function_start_offset (gdbarch
);
3606 if (gdbarch_skip_entrypoint_p (gdbarch
))
3607 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
3608 ecs
->stop_func_start
);
3610 ecs
->stop_func_filled_in
= 1;
3615 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
3617 static enum stop_kind
3618 get_inferior_stop_soon (ptid_t ptid
)
3620 struct inferior
*inf
= find_inferior_ptid (ptid
);
3622 gdb_assert (inf
!= NULL
);
3623 return inf
->control
.stop_soon
;
3626 /* Given an execution control state that has been freshly filled in by
3627 an event from the inferior, figure out what it means and take
3630 The alternatives are:
3632 1) stop_waiting and return; to really stop and return to the
3635 2) keep_going and return; to wait for the next event (set
3636 ecs->event_thread->stepping_over_breakpoint to 1 to single step
3640 handle_inferior_event (struct execution_control_state
*ecs
)
3642 enum stop_kind stop_soon
;
3644 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3646 /* We had an event in the inferior, but we are not interested in
3647 handling it at this level. The lower layers have already
3648 done what needs to be done, if anything.
3650 One of the possible circumstances for this is when the
3651 inferior produces output for the console. The inferior has
3652 not stopped, and we are ignoring the event. Another possible
3653 circumstance is any event which the lower level knows will be
3654 reported multiple times without an intervening resume. */
3656 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3657 prepare_to_wait (ecs
);
3661 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3662 && target_can_async_p () && !sync_execution
)
3664 /* There were no unwaited-for children left in the target, but,
3665 we're not synchronously waiting for events either. Just
3666 ignore. Otherwise, if we were running a synchronous
3667 execution command, we need to cancel it and give the user
3668 back the terminal. */
3670 fprintf_unfiltered (gdb_stdlog
,
3671 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3672 prepare_to_wait (ecs
);
3676 /* Cache the last pid/waitstatus. */
3677 set_last_target_status (ecs
->ptid
, ecs
->ws
);
3679 /* Always clear state belonging to the previous time we stopped. */
3680 stop_stack_dummy
= STOP_NONE
;
3682 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3684 /* No unwaited-for children left. IOW, all resumed children
3687 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3689 stop_print_frame
= 0;
3694 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3695 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3697 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3698 /* If it's a new thread, add it to the thread database. */
3699 if (ecs
->event_thread
== NULL
)
3700 ecs
->event_thread
= add_thread (ecs
->ptid
);
3702 /* Disable range stepping. If the next step request could use a
3703 range, this will be end up re-enabled then. */
3704 ecs
->event_thread
->control
.may_range_step
= 0;
3707 /* Dependent on valid ECS->EVENT_THREAD. */
3708 adjust_pc_after_break (ecs
);
3710 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3711 reinit_frame_cache ();
3713 breakpoint_retire_moribund ();
3715 /* First, distinguish signals caused by the debugger from signals
3716 that have to do with the program's own actions. Note that
3717 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3718 on the operating system version. Here we detect when a SIGILL or
3719 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3720 something similar for SIGSEGV, since a SIGSEGV will be generated
3721 when we're trying to execute a breakpoint instruction on a
3722 non-executable stack. This happens for call dummy breakpoints
3723 for architectures like SPARC that place call dummies on the
3725 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3726 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3727 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3728 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3730 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3732 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3733 regcache_read_pc (regcache
)))
3736 fprintf_unfiltered (gdb_stdlog
,
3737 "infrun: Treating signal as SIGTRAP\n");
3738 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3742 /* Mark the non-executing threads accordingly. In all-stop, all
3743 threads of all processes are stopped when we get any event
3744 reported. In non-stop mode, only the event thread stops. If
3745 we're handling a process exit in non-stop mode, there's nothing
3746 to do, as threads of the dead process are gone, and threads of
3747 any other process were left running. */
3749 set_executing (minus_one_ptid
, 0);
3750 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3751 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3752 set_executing (ecs
->ptid
, 0);
3754 switch (ecs
->ws
.kind
)
3756 case TARGET_WAITKIND_LOADED
:
3758 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3759 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3760 context_switch (ecs
->ptid
);
3761 /* Ignore gracefully during startup of the inferior, as it might
3762 be the shell which has just loaded some objects, otherwise
3763 add the symbols for the newly loaded objects. Also ignore at
3764 the beginning of an attach or remote session; we will query
3765 the full list of libraries once the connection is
3768 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
3769 if (stop_soon
== NO_STOP_QUIETLY
)
3771 struct regcache
*regcache
;
3773 regcache
= get_thread_regcache (ecs
->ptid
);
3775 handle_solib_event ();
3777 ecs
->event_thread
->control
.stop_bpstat
3778 = bpstat_stop_status (get_regcache_aspace (regcache
),
3779 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3781 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3783 /* A catchpoint triggered. */
3784 process_event_stop_test (ecs
);
3788 /* If requested, stop when the dynamic linker notifies
3789 gdb of events. This allows the user to get control
3790 and place breakpoints in initializer routines for
3791 dynamically loaded objects (among other things). */
3792 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3793 if (stop_on_solib_events
)
3795 /* Make sure we print "Stopped due to solib-event" in
3797 stop_print_frame
= 1;
3804 /* If we are skipping through a shell, or through shared library
3805 loading that we aren't interested in, resume the program. If
3806 we're running the program normally, also resume. */
3807 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3809 /* Loading of shared libraries might have changed breakpoint
3810 addresses. Make sure new breakpoints are inserted. */
3811 if (stop_soon
== NO_STOP_QUIETLY
)
3812 insert_breakpoints ();
3813 resume (0, GDB_SIGNAL_0
);
3814 prepare_to_wait (ecs
);
3818 /* But stop if we're attaching or setting up a remote
3820 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3821 || stop_soon
== STOP_QUIETLY_REMOTE
)
3824 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3829 internal_error (__FILE__
, __LINE__
,
3830 _("unhandled stop_soon: %d"), (int) stop_soon
);
3832 case TARGET_WAITKIND_SPURIOUS
:
3834 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3835 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3836 context_switch (ecs
->ptid
);
3837 resume (0, GDB_SIGNAL_0
);
3838 prepare_to_wait (ecs
);
3841 case TARGET_WAITKIND_EXITED
:
3842 case TARGET_WAITKIND_SIGNALLED
:
3845 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3846 fprintf_unfiltered (gdb_stdlog
,
3847 "infrun: TARGET_WAITKIND_EXITED\n");
3849 fprintf_unfiltered (gdb_stdlog
,
3850 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3853 inferior_ptid
= ecs
->ptid
;
3854 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
3855 set_current_program_space (current_inferior ()->pspace
);
3856 handle_vfork_child_exec_or_exit (0);
3857 target_terminal_ours (); /* Must do this before mourn anyway. */
3859 /* Clearing any previous state of convenience variables. */
3860 clear_exit_convenience_vars ();
3862 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3864 /* Record the exit code in the convenience variable $_exitcode, so
3865 that the user can inspect this again later. */
3866 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3867 (LONGEST
) ecs
->ws
.value
.integer
);
3869 /* Also record this in the inferior itself. */
3870 current_inferior ()->has_exit_code
= 1;
3871 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3873 /* Support the --return-child-result option. */
3874 return_child_result_value
= ecs
->ws
.value
.integer
;
3876 observer_notify_exited (ecs
->ws
.value
.integer
);
3880 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3881 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3883 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
3885 /* Set the value of the internal variable $_exitsignal,
3886 which holds the signal uncaught by the inferior. */
3887 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
3888 gdbarch_gdb_signal_to_target (gdbarch
,
3889 ecs
->ws
.value
.sig
));
3893 /* We don't have access to the target's method used for
3894 converting between signal numbers (GDB's internal
3895 representation <-> target's representation).
3896 Therefore, we cannot do a good job at displaying this
3897 information to the user. It's better to just warn
3898 her about it (if infrun debugging is enabled), and
3901 fprintf_filtered (gdb_stdlog
, _("\
3902 Cannot fill $_exitsignal with the correct signal number.\n"));
3905 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
3908 gdb_flush (gdb_stdout
);
3909 target_mourn_inferior ();
3910 stop_print_frame
= 0;
3914 /* The following are the only cases in which we keep going;
3915 the above cases end in a continue or goto. */
3916 case TARGET_WAITKIND_FORKED
:
3917 case TARGET_WAITKIND_VFORKED
:
3920 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3921 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3923 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
3926 /* Check whether the inferior is displaced stepping. */
3928 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3929 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3930 struct displaced_step_inferior_state
*displaced
3931 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3933 /* If checking displaced stepping is supported, and thread
3934 ecs->ptid is displaced stepping. */
3935 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3937 struct inferior
*parent_inf
3938 = find_inferior_ptid (ecs
->ptid
);
3939 struct regcache
*child_regcache
;
3940 CORE_ADDR parent_pc
;
3942 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3943 indicating that the displaced stepping of syscall instruction
3944 has been done. Perform cleanup for parent process here. Note
3945 that this operation also cleans up the child process for vfork,
3946 because their pages are shared. */
3947 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3949 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3951 /* Restore scratch pad for child process. */
3952 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3955 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3956 the child's PC is also within the scratchpad. Set the child's PC
3957 to the parent's PC value, which has already been fixed up.
3958 FIXME: we use the parent's aspace here, although we're touching
3959 the child, because the child hasn't been added to the inferior
3960 list yet at this point. */
3963 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3965 parent_inf
->aspace
);
3966 /* Read PC value of parent process. */
3967 parent_pc
= regcache_read_pc (regcache
);
3969 if (debug_displaced
)
3970 fprintf_unfiltered (gdb_stdlog
,
3971 "displaced: write child pc from %s to %s\n",
3973 regcache_read_pc (child_regcache
)),
3974 paddress (gdbarch
, parent_pc
));
3976 regcache_write_pc (child_regcache
, parent_pc
);
3980 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3981 context_switch (ecs
->ptid
);
3983 /* Immediately detach breakpoints from the child before there's
3984 any chance of letting the user delete breakpoints from the
3985 breakpoint lists. If we don't do this early, it's easy to
3986 leave left over traps in the child, vis: "break foo; catch
3987 fork; c; <fork>; del; c; <child calls foo>". We only follow
3988 the fork on the last `continue', and by that time the
3989 breakpoint at "foo" is long gone from the breakpoint table.
3990 If we vforked, then we don't need to unpatch here, since both
3991 parent and child are sharing the same memory pages; we'll
3992 need to unpatch at follow/detach time instead to be certain
3993 that new breakpoints added between catchpoint hit time and
3994 vfork follow are detached. */
3995 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3997 /* This won't actually modify the breakpoint list, but will
3998 physically remove the breakpoints from the child. */
3999 detach_breakpoints (ecs
->ws
.value
.related_pid
);
4002 delete_just_stopped_threads_single_step_breakpoints ();
4004 /* In case the event is caught by a catchpoint, remember that
4005 the event is to be followed at the next resume of the thread,
4006 and not immediately. */
4007 ecs
->event_thread
->pending_follow
= ecs
->ws
;
4009 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4011 ecs
->event_thread
->control
.stop_bpstat
4012 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4013 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4015 /* If no catchpoint triggered for this, then keep going. Note
4016 that we're interested in knowing the bpstat actually causes a
4017 stop, not just if it may explain the signal. Software
4018 watchpoints, for example, always appear in the bpstat. */
4019 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4025 = (follow_fork_mode_string
== follow_fork_mode_child
);
4027 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4029 should_resume
= follow_fork ();
4032 child
= ecs
->ws
.value
.related_pid
;
4034 /* In non-stop mode, also resume the other branch. */
4035 if (non_stop
&& !detach_fork
)
4038 switch_to_thread (parent
);
4040 switch_to_thread (child
);
4042 ecs
->event_thread
= inferior_thread ();
4043 ecs
->ptid
= inferior_ptid
;
4048 switch_to_thread (child
);
4050 switch_to_thread (parent
);
4052 ecs
->event_thread
= inferior_thread ();
4053 ecs
->ptid
= inferior_ptid
;
4061 process_event_stop_test (ecs
);
4064 case TARGET_WAITKIND_VFORK_DONE
:
4065 /* Done with the shared memory region. Re-insert breakpoints in
4066 the parent, and keep going. */
4069 fprintf_unfiltered (gdb_stdlog
,
4070 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
4072 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4073 context_switch (ecs
->ptid
);
4075 current_inferior ()->waiting_for_vfork_done
= 0;
4076 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
4077 /* This also takes care of reinserting breakpoints in the
4078 previously locked inferior. */
4082 case TARGET_WAITKIND_EXECD
:
4084 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
4086 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4087 context_switch (ecs
->ptid
);
4089 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4091 /* Do whatever is necessary to the parent branch of the vfork. */
4092 handle_vfork_child_exec_or_exit (1);
4094 /* This causes the eventpoints and symbol table to be reset.
4095 Must do this now, before trying to determine whether to
4097 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
4099 ecs
->event_thread
->control
.stop_bpstat
4100 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4101 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4103 /* Note that this may be referenced from inside
4104 bpstat_stop_status above, through inferior_has_execd. */
4105 xfree (ecs
->ws
.value
.execd_pathname
);
4106 ecs
->ws
.value
.execd_pathname
= NULL
;
4108 /* If no catchpoint triggered for this, then keep going. */
4109 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4111 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4115 process_event_stop_test (ecs
);
4118 /* Be careful not to try to gather much state about a thread
4119 that's in a syscall. It's frequently a losing proposition. */
4120 case TARGET_WAITKIND_SYSCALL_ENTRY
:
4122 fprintf_unfiltered (gdb_stdlog
,
4123 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
4124 /* Getting the current syscall number. */
4125 if (handle_syscall_event (ecs
) == 0)
4126 process_event_stop_test (ecs
);
4129 /* Before examining the threads further, step this thread to
4130 get it entirely out of the syscall. (We get notice of the
4131 event when the thread is just on the verge of exiting a
4132 syscall. Stepping one instruction seems to get it back
4134 case TARGET_WAITKIND_SYSCALL_RETURN
:
4136 fprintf_unfiltered (gdb_stdlog
,
4137 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
4138 if (handle_syscall_event (ecs
) == 0)
4139 process_event_stop_test (ecs
);
4142 case TARGET_WAITKIND_STOPPED
:
4144 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
4145 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
4146 handle_signal_stop (ecs
);
4149 case TARGET_WAITKIND_NO_HISTORY
:
4151 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
4152 /* Reverse execution: target ran out of history info. */
4154 delete_just_stopped_threads_single_step_breakpoints ();
4155 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4156 observer_notify_no_history ();
4162 /* Come here when the program has stopped with a signal. */
4165 handle_signal_stop (struct execution_control_state
*ecs
)
4167 struct frame_info
*frame
;
4168 struct gdbarch
*gdbarch
;
4169 int stopped_by_watchpoint
;
4170 enum stop_kind stop_soon
;
4173 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
4175 /* Do we need to clean up the state of a thread that has
4176 completed a displaced single-step? (Doing so usually affects
4177 the PC, so do it here, before we set stop_pc.) */
4178 displaced_step_fixup (ecs
->ptid
,
4179 ecs
->event_thread
->suspend
.stop_signal
);
4181 /* If we either finished a single-step or hit a breakpoint, but
4182 the user wanted this thread to be stopped, pretend we got a
4183 SIG0 (generic unsignaled stop). */
4184 if (ecs
->event_thread
->stop_requested
4185 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4186 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4188 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4192 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4193 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4194 struct cleanup
*old_chain
= save_inferior_ptid ();
4196 inferior_ptid
= ecs
->ptid
;
4198 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
4199 paddress (gdbarch
, stop_pc
));
4200 if (target_stopped_by_watchpoint ())
4204 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
4206 if (target_stopped_data_address (¤t_target
, &addr
))
4207 fprintf_unfiltered (gdb_stdlog
,
4208 "infrun: stopped data address = %s\n",
4209 paddress (gdbarch
, addr
));
4211 fprintf_unfiltered (gdb_stdlog
,
4212 "infrun: (no data address available)\n");
4215 do_cleanups (old_chain
);
4218 /* This is originated from start_remote(), start_inferior() and
4219 shared libraries hook functions. */
4220 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4221 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4223 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4224 context_switch (ecs
->ptid
);
4226 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4227 stop_print_frame
= 1;
4232 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4235 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4236 context_switch (ecs
->ptid
);
4238 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4239 stop_print_frame
= 0;
4244 /* This originates from attach_command(). We need to overwrite
4245 the stop_signal here, because some kernels don't ignore a
4246 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4247 See more comments in inferior.h. On the other hand, if we
4248 get a non-SIGSTOP, report it to the user - assume the backend
4249 will handle the SIGSTOP if it should show up later.
4251 Also consider that the attach is complete when we see a
4252 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4253 target extended-remote report it instead of a SIGSTOP
4254 (e.g. gdbserver). We already rely on SIGTRAP being our
4255 signal, so this is no exception.
4257 Also consider that the attach is complete when we see a
4258 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4259 the target to stop all threads of the inferior, in case the
4260 low level attach operation doesn't stop them implicitly. If
4261 they weren't stopped implicitly, then the stub will report a
4262 GDB_SIGNAL_0, meaning: stopped for no particular reason
4263 other than GDB's request. */
4264 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4265 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4266 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4267 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4269 stop_print_frame
= 1;
4271 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4275 /* See if something interesting happened to the non-current thread. If
4276 so, then switch to that thread. */
4277 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4280 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
4282 context_switch (ecs
->ptid
);
4284 if (deprecated_context_hook
)
4285 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
4288 /* At this point, get hold of the now-current thread's frame. */
4289 frame
= get_current_frame ();
4290 gdbarch
= get_frame_arch (frame
);
4292 /* Pull the single step breakpoints out of the target. */
4293 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4295 struct regcache
*regcache
;
4296 struct address_space
*aspace
;
4299 regcache
= get_thread_regcache (ecs
->ptid
);
4300 aspace
= get_regcache_aspace (regcache
);
4301 pc
= regcache_read_pc (regcache
);
4303 /* However, before doing so, if this single-step breakpoint was
4304 actually for another thread, set this thread up for moving
4306 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
4309 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
4313 fprintf_unfiltered (gdb_stdlog
,
4314 "infrun: [%s] hit another thread's "
4315 "single-step breakpoint\n",
4316 target_pid_to_str (ecs
->ptid
));
4318 ecs
->hit_singlestep_breakpoint
= 1;
4325 fprintf_unfiltered (gdb_stdlog
,
4326 "infrun: [%s] hit its "
4327 "single-step breakpoint\n",
4328 target_pid_to_str (ecs
->ptid
));
4332 delete_just_stopped_threads_single_step_breakpoints ();
4334 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4335 && ecs
->event_thread
->control
.trap_expected
4336 && ecs
->event_thread
->stepping_over_watchpoint
)
4337 stopped_by_watchpoint
= 0;
4339 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4341 /* If necessary, step over this watchpoint. We'll be back to display
4343 if (stopped_by_watchpoint
4344 && (target_have_steppable_watchpoint
4345 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4347 /* At this point, we are stopped at an instruction which has
4348 attempted to write to a piece of memory under control of
4349 a watchpoint. The instruction hasn't actually executed
4350 yet. If we were to evaluate the watchpoint expression
4351 now, we would get the old value, and therefore no change
4352 would seem to have occurred.
4354 In order to make watchpoints work `right', we really need
4355 to complete the memory write, and then evaluate the
4356 watchpoint expression. We do this by single-stepping the
4359 It may not be necessary to disable the watchpoint to step over
4360 it. For example, the PA can (with some kernel cooperation)
4361 single step over a watchpoint without disabling the watchpoint.
4363 It is far more common to need to disable a watchpoint to step
4364 the inferior over it. If we have non-steppable watchpoints,
4365 we must disable the current watchpoint; it's simplest to
4366 disable all watchpoints.
4368 Any breakpoint at PC must also be stepped over -- if there's
4369 one, it will have already triggered before the watchpoint
4370 triggered, and we either already reported it to the user, or
4371 it didn't cause a stop and we called keep_going. In either
4372 case, if there was a breakpoint at PC, we must be trying to
4374 ecs
->event_thread
->stepping_over_watchpoint
= 1;
4379 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4380 ecs
->event_thread
->stepping_over_watchpoint
= 0;
4381 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4382 ecs
->event_thread
->control
.stop_step
= 0;
4383 stop_print_frame
= 1;
4384 stopped_by_random_signal
= 0;
4386 /* Hide inlined functions starting here, unless we just performed stepi or
4387 nexti. After stepi and nexti, always show the innermost frame (not any
4388 inline function call sites). */
4389 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4391 struct address_space
*aspace
=
4392 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4394 /* skip_inline_frames is expensive, so we avoid it if we can
4395 determine that the address is one where functions cannot have
4396 been inlined. This improves performance with inferiors that
4397 load a lot of shared libraries, because the solib event
4398 breakpoint is defined as the address of a function (i.e. not
4399 inline). Note that we have to check the previous PC as well
4400 as the current one to catch cases when we have just
4401 single-stepped off a breakpoint prior to reinstating it.
4402 Note that we're assuming that the code we single-step to is
4403 not inline, but that's not definitive: there's nothing
4404 preventing the event breakpoint function from containing
4405 inlined code, and the single-step ending up there. If the
4406 user had set a breakpoint on that inlined code, the missing
4407 skip_inline_frames call would break things. Fortunately
4408 that's an extremely unlikely scenario. */
4409 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4410 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4411 && ecs
->event_thread
->control
.trap_expected
4412 && pc_at_non_inline_function (aspace
,
4413 ecs
->event_thread
->prev_pc
,
4416 skip_inline_frames (ecs
->ptid
);
4418 /* Re-fetch current thread's frame in case that invalidated
4420 frame
= get_current_frame ();
4421 gdbarch
= get_frame_arch (frame
);
4425 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4426 && ecs
->event_thread
->control
.trap_expected
4427 && gdbarch_single_step_through_delay_p (gdbarch
)
4428 && currently_stepping (ecs
->event_thread
))
4430 /* We're trying to step off a breakpoint. Turns out that we're
4431 also on an instruction that needs to be stepped multiple
4432 times before it's been fully executing. E.g., architectures
4433 with a delay slot. It needs to be stepped twice, once for
4434 the instruction and once for the delay slot. */
4435 int step_through_delay
4436 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4438 if (debug_infrun
&& step_through_delay
)
4439 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4440 if (ecs
->event_thread
->control
.step_range_end
== 0
4441 && step_through_delay
)
4443 /* The user issued a continue when stopped at a breakpoint.
4444 Set up for another trap and get out of here. */
4445 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4449 else if (step_through_delay
)
4451 /* The user issued a step when stopped at a breakpoint.
4452 Maybe we should stop, maybe we should not - the delay
4453 slot *might* correspond to a line of source. In any
4454 case, don't decide that here, just set
4455 ecs->stepping_over_breakpoint, making sure we
4456 single-step again before breakpoints are re-inserted. */
4457 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4461 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4462 handles this event. */
4463 ecs
->event_thread
->control
.stop_bpstat
4464 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4465 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4467 /* Following in case break condition called a
4469 stop_print_frame
= 1;
4471 /* This is where we handle "moribund" watchpoints. Unlike
4472 software breakpoints traps, hardware watchpoint traps are
4473 always distinguishable from random traps. If no high-level
4474 watchpoint is associated with the reported stop data address
4475 anymore, then the bpstat does not explain the signal ---
4476 simply make sure to ignore it if `stopped_by_watchpoint' is
4480 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4481 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4483 && stopped_by_watchpoint
)
4484 fprintf_unfiltered (gdb_stdlog
,
4485 "infrun: no user watchpoint explains "
4486 "watchpoint SIGTRAP, ignoring\n");
4488 /* NOTE: cagney/2003-03-29: These checks for a random signal
4489 at one stage in the past included checks for an inferior
4490 function call's call dummy's return breakpoint. The original
4491 comment, that went with the test, read:
4493 ``End of a stack dummy. Some systems (e.g. Sony news) give
4494 another signal besides SIGTRAP, so check here as well as
4497 If someone ever tries to get call dummys on a
4498 non-executable stack to work (where the target would stop
4499 with something like a SIGSEGV), then those tests might need
4500 to be re-instated. Given, however, that the tests were only
4501 enabled when momentary breakpoints were not being used, I
4502 suspect that it won't be the case.
4504 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4505 be necessary for call dummies on a non-executable stack on
4508 /* See if the breakpoints module can explain the signal. */
4510 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4511 ecs
->event_thread
->suspend
.stop_signal
);
4513 /* If not, perhaps stepping/nexting can. */
4515 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4516 && currently_stepping (ecs
->event_thread
));
4518 /* Perhaps the thread hit a single-step breakpoint of _another_
4519 thread. Single-step breakpoints are transparent to the
4520 breakpoints module. */
4522 random_signal
= !ecs
->hit_singlestep_breakpoint
;
4524 /* No? Perhaps we got a moribund watchpoint. */
4526 random_signal
= !stopped_by_watchpoint
;
4528 /* For the program's own signals, act according to
4529 the signal handling tables. */
4533 /* Signal not for debugging purposes. */
4534 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
4535 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
4538 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
4539 gdb_signal_to_symbol_string (stop_signal
));
4541 stopped_by_random_signal
= 1;
4543 /* Always stop on signals if we're either just gaining control
4544 of the program, or the user explicitly requested this thread
4545 to remain stopped. */
4546 if (stop_soon
!= NO_STOP_QUIETLY
4547 || ecs
->event_thread
->stop_requested
4549 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4555 /* Notify observers the signal has "handle print" set. Note we
4556 returned early above if stopping; normal_stop handles the
4557 printing in that case. */
4558 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4560 /* The signal table tells us to print about this signal. */
4561 target_terminal_ours_for_output ();
4562 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
4563 target_terminal_inferior ();
4566 /* Clear the signal if it should not be passed. */
4567 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4568 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4570 if (ecs
->event_thread
->prev_pc
== stop_pc
4571 && ecs
->event_thread
->control
.trap_expected
4572 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4574 /* We were just starting a new sequence, attempting to
4575 single-step off of a breakpoint and expecting a SIGTRAP.
4576 Instead this signal arrives. This signal will take us out
4577 of the stepping range so GDB needs to remember to, when
4578 the signal handler returns, resume stepping off that
4580 /* To simplify things, "continue" is forced to use the same
4581 code paths as single-step - set a breakpoint at the
4582 signal return address and then, once hit, step off that
4585 fprintf_unfiltered (gdb_stdlog
,
4586 "infrun: signal arrived while stepping over "
4589 insert_hp_step_resume_breakpoint_at_frame (frame
);
4590 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4591 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4592 ecs
->event_thread
->control
.trap_expected
= 0;
4594 /* If we were nexting/stepping some other thread, switch to
4595 it, so that we don't continue it, losing control. */
4596 if (!switch_back_to_stepped_thread (ecs
))
4601 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4602 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4603 || ecs
->event_thread
->control
.step_range_end
== 1)
4604 && frame_id_eq (get_stack_frame_id (frame
),
4605 ecs
->event_thread
->control
.step_stack_frame_id
)
4606 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4608 /* The inferior is about to take a signal that will take it
4609 out of the single step range. Set a breakpoint at the
4610 current PC (which is presumably where the signal handler
4611 will eventually return) and then allow the inferior to
4614 Note that this is only needed for a signal delivered
4615 while in the single-step range. Nested signals aren't a
4616 problem as they eventually all return. */
4618 fprintf_unfiltered (gdb_stdlog
,
4619 "infrun: signal may take us out of "
4620 "single-step range\n");
4622 insert_hp_step_resume_breakpoint_at_frame (frame
);
4623 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4624 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4625 ecs
->event_thread
->control
.trap_expected
= 0;
4630 /* Note: step_resume_breakpoint may be non-NULL. This occures
4631 when either there's a nested signal, or when there's a
4632 pending signal enabled just as the signal handler returns
4633 (leaving the inferior at the step-resume-breakpoint without
4634 actually executing it). Either way continue until the
4635 breakpoint is really hit. */
4637 if (!switch_back_to_stepped_thread (ecs
))
4640 fprintf_unfiltered (gdb_stdlog
,
4641 "infrun: random signal, keep going\n");
4648 process_event_stop_test (ecs
);
4651 /* Come here when we've got some debug event / signal we can explain
4652 (IOW, not a random signal), and test whether it should cause a
4653 stop, or whether we should resume the inferior (transparently).
4654 E.g., could be a breakpoint whose condition evaluates false; we
4655 could be still stepping within the line; etc. */
4658 process_event_stop_test (struct execution_control_state
*ecs
)
4660 struct symtab_and_line stop_pc_sal
;
4661 struct frame_info
*frame
;
4662 struct gdbarch
*gdbarch
;
4663 CORE_ADDR jmp_buf_pc
;
4664 struct bpstat_what what
;
4666 /* Handle cases caused by hitting a breakpoint. */
4668 frame
= get_current_frame ();
4669 gdbarch
= get_frame_arch (frame
);
4671 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4673 if (what
.call_dummy
)
4675 stop_stack_dummy
= what
.call_dummy
;
4678 /* If we hit an internal event that triggers symbol changes, the
4679 current frame will be invalidated within bpstat_what (e.g., if we
4680 hit an internal solib event). Re-fetch it. */
4681 frame
= get_current_frame ();
4682 gdbarch
= get_frame_arch (frame
);
4684 switch (what
.main_action
)
4686 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4687 /* If we hit the breakpoint at longjmp while stepping, we
4688 install a momentary breakpoint at the target of the
4692 fprintf_unfiltered (gdb_stdlog
,
4693 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4695 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4697 if (what
.is_longjmp
)
4699 struct value
*arg_value
;
4701 /* If we set the longjmp breakpoint via a SystemTap probe,
4702 then use it to extract the arguments. The destination PC
4703 is the third argument to the probe. */
4704 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4707 jmp_buf_pc
= value_as_address (arg_value
);
4708 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
4710 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4711 || !gdbarch_get_longjmp_target (gdbarch
,
4712 frame
, &jmp_buf_pc
))
4715 fprintf_unfiltered (gdb_stdlog
,
4716 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4717 "(!gdbarch_get_longjmp_target)\n");
4722 /* Insert a breakpoint at resume address. */
4723 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4726 check_exception_resume (ecs
, frame
);
4730 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4732 struct frame_info
*init_frame
;
4734 /* There are several cases to consider.
4736 1. The initiating frame no longer exists. In this case we
4737 must stop, because the exception or longjmp has gone too
4740 2. The initiating frame exists, and is the same as the
4741 current frame. We stop, because the exception or longjmp
4744 3. The initiating frame exists and is different from the
4745 current frame. This means the exception or longjmp has
4746 been caught beneath the initiating frame, so keep going.
4748 4. longjmp breakpoint has been placed just to protect
4749 against stale dummy frames and user is not interested in
4750 stopping around longjmps. */
4753 fprintf_unfiltered (gdb_stdlog
,
4754 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4756 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4758 delete_exception_resume_breakpoint (ecs
->event_thread
);
4760 if (what
.is_longjmp
)
4762 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
4764 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4772 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4776 struct frame_id current_id
4777 = get_frame_id (get_current_frame ());
4778 if (frame_id_eq (current_id
,
4779 ecs
->event_thread
->initiating_frame
))
4781 /* Case 2. Fall through. */
4791 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
4793 delete_step_resume_breakpoint (ecs
->event_thread
);
4795 end_stepping_range (ecs
);
4799 case BPSTAT_WHAT_SINGLE
:
4801 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4802 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4803 /* Still need to check other stuff, at least the case where we
4804 are stepping and step out of the right range. */
4807 case BPSTAT_WHAT_STEP_RESUME
:
4809 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4811 delete_step_resume_breakpoint (ecs
->event_thread
);
4812 if (ecs
->event_thread
->control
.proceed_to_finish
4813 && execution_direction
== EXEC_REVERSE
)
4815 struct thread_info
*tp
= ecs
->event_thread
;
4817 /* We are finishing a function in reverse, and just hit the
4818 step-resume breakpoint at the start address of the
4819 function, and we're almost there -- just need to back up
4820 by one more single-step, which should take us back to the
4822 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4826 fill_in_stop_func (gdbarch
, ecs
);
4827 if (stop_pc
== ecs
->stop_func_start
4828 && execution_direction
== EXEC_REVERSE
)
4830 /* We are stepping over a function call in reverse, and just
4831 hit the step-resume breakpoint at the start address of
4832 the function. Go back to single-stepping, which should
4833 take us back to the function call. */
4834 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4840 case BPSTAT_WHAT_STOP_NOISY
:
4842 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4843 stop_print_frame
= 1;
4845 /* Assume the thread stopped for a breapoint. We'll still check
4846 whether a/the breakpoint is there when the thread is next
4848 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4853 case BPSTAT_WHAT_STOP_SILENT
:
4855 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4856 stop_print_frame
= 0;
4858 /* Assume the thread stopped for a breapoint. We'll still check
4859 whether a/the breakpoint is there when the thread is next
4861 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4865 case BPSTAT_WHAT_HP_STEP_RESUME
:
4867 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4869 delete_step_resume_breakpoint (ecs
->event_thread
);
4870 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4872 /* Back when the step-resume breakpoint was inserted, we
4873 were trying to single-step off a breakpoint. Go back to
4875 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4876 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4882 case BPSTAT_WHAT_KEEP_CHECKING
:
4886 /* If we stepped a permanent breakpoint and we had a high priority
4887 step-resume breakpoint for the address we stepped, but we didn't
4888 hit it, then we must have stepped into the signal handler. The
4889 step-resume was only necessary to catch the case of _not_
4890 stepping into the handler, so delete it, and fall through to
4891 checking whether the step finished. */
4892 if (ecs
->event_thread
->stepped_breakpoint
)
4894 struct breakpoint
*sr_bp
4895 = ecs
->event_thread
->control
.step_resume_breakpoint
;
4897 if (sr_bp
->loc
->permanent
4898 && sr_bp
->type
== bp_hp_step_resume
4899 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
4902 fprintf_unfiltered (gdb_stdlog
,
4903 "infrun: stepped permanent breakpoint, stopped in "
4905 delete_step_resume_breakpoint (ecs
->event_thread
);
4906 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4910 /* We come here if we hit a breakpoint but should not stop for it.
4911 Possibly we also were stepping and should stop for that. So fall
4912 through and test for stepping. But, if not stepping, do not
4915 /* In all-stop mode, if we're currently stepping but have stopped in
4916 some other thread, we need to switch back to the stepped thread. */
4917 if (switch_back_to_stepped_thread (ecs
))
4920 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4923 fprintf_unfiltered (gdb_stdlog
,
4924 "infrun: step-resume breakpoint is inserted\n");
4926 /* Having a step-resume breakpoint overrides anything
4927 else having to do with stepping commands until
4928 that breakpoint is reached. */
4933 if (ecs
->event_thread
->control
.step_range_end
== 0)
4936 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4937 /* Likewise if we aren't even stepping. */
4942 /* Re-fetch current thread's frame in case the code above caused
4943 the frame cache to be re-initialized, making our FRAME variable
4944 a dangling pointer. */
4945 frame
= get_current_frame ();
4946 gdbarch
= get_frame_arch (frame
);
4947 fill_in_stop_func (gdbarch
, ecs
);
4949 /* If stepping through a line, keep going if still within it.
4951 Note that step_range_end is the address of the first instruction
4952 beyond the step range, and NOT the address of the last instruction
4955 Note also that during reverse execution, we may be stepping
4956 through a function epilogue and therefore must detect when
4957 the current-frame changes in the middle of a line. */
4959 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4960 && (execution_direction
!= EXEC_REVERSE
4961 || frame_id_eq (get_frame_id (frame
),
4962 ecs
->event_thread
->control
.step_frame_id
)))
4966 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4967 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4968 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4970 /* Tentatively re-enable range stepping; `resume' disables it if
4971 necessary (e.g., if we're stepping over a breakpoint or we
4972 have software watchpoints). */
4973 ecs
->event_thread
->control
.may_range_step
= 1;
4975 /* When stepping backward, stop at beginning of line range
4976 (unless it's the function entry point, in which case
4977 keep going back to the call point). */
4978 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4979 && stop_pc
!= ecs
->stop_func_start
4980 && execution_direction
== EXEC_REVERSE
)
4981 end_stepping_range (ecs
);
4988 /* We stepped out of the stepping range. */
4990 /* If we are stepping at the source level and entered the runtime
4991 loader dynamic symbol resolution code...
4993 EXEC_FORWARD: we keep on single stepping until we exit the run
4994 time loader code and reach the callee's address.
4996 EXEC_REVERSE: we've already executed the callee (backward), and
4997 the runtime loader code is handled just like any other
4998 undebuggable function call. Now we need only keep stepping
4999 backward through the trampoline code, and that's handled further
5000 down, so there is nothing for us to do here. */
5002 if (execution_direction
!= EXEC_REVERSE
5003 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5004 && in_solib_dynsym_resolve_code (stop_pc
))
5006 CORE_ADDR pc_after_resolver
=
5007 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
5010 fprintf_unfiltered (gdb_stdlog
,
5011 "infrun: stepped into dynsym resolve code\n");
5013 if (pc_after_resolver
)
5015 /* Set up a step-resume breakpoint at the address
5016 indicated by SKIP_SOLIB_RESOLVER. */
5017 struct symtab_and_line sr_sal
;
5020 sr_sal
.pc
= pc_after_resolver
;
5021 sr_sal
.pspace
= get_frame_program_space (frame
);
5023 insert_step_resume_breakpoint_at_sal (gdbarch
,
5024 sr_sal
, null_frame_id
);
5031 if (ecs
->event_thread
->control
.step_range_end
!= 1
5032 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5033 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5034 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
5037 fprintf_unfiltered (gdb_stdlog
,
5038 "infrun: stepped into signal trampoline\n");
5039 /* The inferior, while doing a "step" or "next", has ended up in
5040 a signal trampoline (either by a signal being delivered or by
5041 the signal handler returning). Just single-step until the
5042 inferior leaves the trampoline (either by calling the handler
5048 /* If we're in the return path from a shared library trampoline,
5049 we want to proceed through the trampoline when stepping. */
5050 /* macro/2012-04-25: This needs to come before the subroutine
5051 call check below as on some targets return trampolines look
5052 like subroutine calls (MIPS16 return thunks). */
5053 if (gdbarch_in_solib_return_trampoline (gdbarch
,
5054 stop_pc
, ecs
->stop_func_name
)
5055 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5057 /* Determine where this trampoline returns. */
5058 CORE_ADDR real_stop_pc
;
5060 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5063 fprintf_unfiltered (gdb_stdlog
,
5064 "infrun: stepped into solib return tramp\n");
5066 /* Only proceed through if we know where it's going. */
5069 /* And put the step-breakpoint there and go until there. */
5070 struct symtab_and_line sr_sal
;
5072 init_sal (&sr_sal
); /* initialize to zeroes */
5073 sr_sal
.pc
= real_stop_pc
;
5074 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5075 sr_sal
.pspace
= get_frame_program_space (frame
);
5077 /* Do not specify what the fp should be when we stop since
5078 on some machines the prologue is where the new fp value
5080 insert_step_resume_breakpoint_at_sal (gdbarch
,
5081 sr_sal
, null_frame_id
);
5083 /* Restart without fiddling with the step ranges or
5090 /* Check for subroutine calls. The check for the current frame
5091 equalling the step ID is not necessary - the check of the
5092 previous frame's ID is sufficient - but it is a common case and
5093 cheaper than checking the previous frame's ID.
5095 NOTE: frame_id_eq will never report two invalid frame IDs as
5096 being equal, so to get into this block, both the current and
5097 previous frame must have valid frame IDs. */
5098 /* The outer_frame_id check is a heuristic to detect stepping
5099 through startup code. If we step over an instruction which
5100 sets the stack pointer from an invalid value to a valid value,
5101 we may detect that as a subroutine call from the mythical
5102 "outermost" function. This could be fixed by marking
5103 outermost frames as !stack_p,code_p,special_p. Then the
5104 initial outermost frame, before sp was valid, would
5105 have code_addr == &_start. See the comment in frame_id_eq
5107 if (!frame_id_eq (get_stack_frame_id (frame
),
5108 ecs
->event_thread
->control
.step_stack_frame_id
)
5109 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
5110 ecs
->event_thread
->control
.step_stack_frame_id
)
5111 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
5113 || step_start_function
!= find_pc_function (stop_pc
))))
5115 CORE_ADDR real_stop_pc
;
5118 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
5120 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
5122 /* I presume that step_over_calls is only 0 when we're
5123 supposed to be stepping at the assembly language level
5124 ("stepi"). Just stop. */
5125 /* And this works the same backward as frontward. MVS */
5126 end_stepping_range (ecs
);
5130 /* Reverse stepping through solib trampolines. */
5132 if (execution_direction
== EXEC_REVERSE
5133 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
5134 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5135 || (ecs
->stop_func_start
== 0
5136 && in_solib_dynsym_resolve_code (stop_pc
))))
5138 /* Any solib trampoline code can be handled in reverse
5139 by simply continuing to single-step. We have already
5140 executed the solib function (backwards), and a few
5141 steps will take us back through the trampoline to the
5147 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5149 /* We're doing a "next".
5151 Normal (forward) execution: set a breakpoint at the
5152 callee's return address (the address at which the caller
5155 Reverse (backward) execution. set the step-resume
5156 breakpoint at the start of the function that we just
5157 stepped into (backwards), and continue to there. When we
5158 get there, we'll need to single-step back to the caller. */
5160 if (execution_direction
== EXEC_REVERSE
)
5162 /* If we're already at the start of the function, we've either
5163 just stepped backward into a single instruction function,
5164 or stepped back out of a signal handler to the first instruction
5165 of the function. Just keep going, which will single-step back
5167 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
5169 struct symtab_and_line sr_sal
;
5171 /* Normal function call return (static or dynamic). */
5173 sr_sal
.pc
= ecs
->stop_func_start
;
5174 sr_sal
.pspace
= get_frame_program_space (frame
);
5175 insert_step_resume_breakpoint_at_sal (gdbarch
,
5176 sr_sal
, null_frame_id
);
5180 insert_step_resume_breakpoint_at_caller (frame
);
5186 /* If we are in a function call trampoline (a stub between the
5187 calling routine and the real function), locate the real
5188 function. That's what tells us (a) whether we want to step
5189 into it at all, and (b) what prologue we want to run to the
5190 end of, if we do step into it. */
5191 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
5192 if (real_stop_pc
== 0)
5193 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5194 if (real_stop_pc
!= 0)
5195 ecs
->stop_func_start
= real_stop_pc
;
5197 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
5199 struct symtab_and_line sr_sal
;
5202 sr_sal
.pc
= ecs
->stop_func_start
;
5203 sr_sal
.pspace
= get_frame_program_space (frame
);
5205 insert_step_resume_breakpoint_at_sal (gdbarch
,
5206 sr_sal
, null_frame_id
);
5211 /* If we have line number information for the function we are
5212 thinking of stepping into and the function isn't on the skip
5215 If there are several symtabs at that PC (e.g. with include
5216 files), just want to know whether *any* of them have line
5217 numbers. find_pc_line handles this. */
5219 struct symtab_and_line tmp_sal
;
5221 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5222 if (tmp_sal
.line
!= 0
5223 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
5226 if (execution_direction
== EXEC_REVERSE
)
5227 handle_step_into_function_backward (gdbarch
, ecs
);
5229 handle_step_into_function (gdbarch
, ecs
);
5234 /* If we have no line number and the step-stop-if-no-debug is
5235 set, we stop the step so that the user has a chance to switch
5236 in assembly mode. */
5237 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5238 && step_stop_if_no_debug
)
5240 end_stepping_range (ecs
);
5244 if (execution_direction
== EXEC_REVERSE
)
5246 /* If we're already at the start of the function, we've either just
5247 stepped backward into a single instruction function without line
5248 number info, or stepped back out of a signal handler to the first
5249 instruction of the function without line number info. Just keep
5250 going, which will single-step back to the caller. */
5251 if (ecs
->stop_func_start
!= stop_pc
)
5253 /* Set a breakpoint at callee's start address.
5254 From there we can step once and be back in the caller. */
5255 struct symtab_and_line sr_sal
;
5258 sr_sal
.pc
= ecs
->stop_func_start
;
5259 sr_sal
.pspace
= get_frame_program_space (frame
);
5260 insert_step_resume_breakpoint_at_sal (gdbarch
,
5261 sr_sal
, null_frame_id
);
5265 /* Set a breakpoint at callee's return address (the address
5266 at which the caller will resume). */
5267 insert_step_resume_breakpoint_at_caller (frame
);
5273 /* Reverse stepping through solib trampolines. */
5275 if (execution_direction
== EXEC_REVERSE
5276 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5278 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5279 || (ecs
->stop_func_start
== 0
5280 && in_solib_dynsym_resolve_code (stop_pc
)))
5282 /* Any solib trampoline code can be handled in reverse
5283 by simply continuing to single-step. We have already
5284 executed the solib function (backwards), and a few
5285 steps will take us back through the trampoline to the
5290 else if (in_solib_dynsym_resolve_code (stop_pc
))
5292 /* Stepped backward into the solib dynsym resolver.
5293 Set a breakpoint at its start and continue, then
5294 one more step will take us out. */
5295 struct symtab_and_line sr_sal
;
5298 sr_sal
.pc
= ecs
->stop_func_start
;
5299 sr_sal
.pspace
= get_frame_program_space (frame
);
5300 insert_step_resume_breakpoint_at_sal (gdbarch
,
5301 sr_sal
, null_frame_id
);
5307 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5309 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5310 the trampoline processing logic, however, there are some trampolines
5311 that have no names, so we should do trampoline handling first. */
5312 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5313 && ecs
->stop_func_name
== NULL
5314 && stop_pc_sal
.line
== 0)
5317 fprintf_unfiltered (gdb_stdlog
,
5318 "infrun: stepped into undebuggable function\n");
5320 /* The inferior just stepped into, or returned to, an
5321 undebuggable function (where there is no debugging information
5322 and no line number corresponding to the address where the
5323 inferior stopped). Since we want to skip this kind of code,
5324 we keep going until the inferior returns from this
5325 function - unless the user has asked us not to (via
5326 set step-mode) or we no longer know how to get back
5327 to the call site. */
5328 if (step_stop_if_no_debug
5329 || !frame_id_p (frame_unwind_caller_id (frame
)))
5331 /* If we have no line number and the step-stop-if-no-debug
5332 is set, we stop the step so that the user has a chance to
5333 switch in assembly mode. */
5334 end_stepping_range (ecs
);
5339 /* Set a breakpoint at callee's return address (the address
5340 at which the caller will resume). */
5341 insert_step_resume_breakpoint_at_caller (frame
);
5347 if (ecs
->event_thread
->control
.step_range_end
== 1)
5349 /* It is stepi or nexti. We always want to stop stepping after
5352 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5353 end_stepping_range (ecs
);
5357 if (stop_pc_sal
.line
== 0)
5359 /* We have no line number information. That means to stop
5360 stepping (does this always happen right after one instruction,
5361 when we do "s" in a function with no line numbers,
5362 or can this happen as a result of a return or longjmp?). */
5364 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5365 end_stepping_range (ecs
);
5369 /* Look for "calls" to inlined functions, part one. If the inline
5370 frame machinery detected some skipped call sites, we have entered
5371 a new inline function. */
5373 if (frame_id_eq (get_frame_id (get_current_frame ()),
5374 ecs
->event_thread
->control
.step_frame_id
)
5375 && inline_skipped_frames (ecs
->ptid
))
5377 struct symtab_and_line call_sal
;
5380 fprintf_unfiltered (gdb_stdlog
,
5381 "infrun: stepped into inlined function\n");
5383 find_frame_sal (get_current_frame (), &call_sal
);
5385 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5387 /* For "step", we're going to stop. But if the call site
5388 for this inlined function is on the same source line as
5389 we were previously stepping, go down into the function
5390 first. Otherwise stop at the call site. */
5392 if (call_sal
.line
== ecs
->event_thread
->current_line
5393 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5394 step_into_inline_frame (ecs
->ptid
);
5396 end_stepping_range (ecs
);
5401 /* For "next", we should stop at the call site if it is on a
5402 different source line. Otherwise continue through the
5403 inlined function. */
5404 if (call_sal
.line
== ecs
->event_thread
->current_line
5405 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5408 end_stepping_range (ecs
);
5413 /* Look for "calls" to inlined functions, part two. If we are still
5414 in the same real function we were stepping through, but we have
5415 to go further up to find the exact frame ID, we are stepping
5416 through a more inlined call beyond its call site. */
5418 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5419 && !frame_id_eq (get_frame_id (get_current_frame ()),
5420 ecs
->event_thread
->control
.step_frame_id
)
5421 && stepped_in_from (get_current_frame (),
5422 ecs
->event_thread
->control
.step_frame_id
))
5425 fprintf_unfiltered (gdb_stdlog
,
5426 "infrun: stepping through inlined function\n");
5428 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5431 end_stepping_range (ecs
);
5435 if ((stop_pc
== stop_pc_sal
.pc
)
5436 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5437 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5439 /* We are at the start of a different line. So stop. Note that
5440 we don't stop if we step into the middle of a different line.
5441 That is said to make things like for (;;) statements work
5444 fprintf_unfiltered (gdb_stdlog
,
5445 "infrun: stepped to a different line\n");
5446 end_stepping_range (ecs
);
5450 /* We aren't done stepping.
5452 Optimize by setting the stepping range to the line.
5453 (We might not be in the original line, but if we entered a
5454 new line in mid-statement, we continue stepping. This makes
5455 things like for(;;) statements work better.) */
5457 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5458 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5459 ecs
->event_thread
->control
.may_range_step
= 1;
5460 set_step_info (frame
, stop_pc_sal
);
5463 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5467 /* In all-stop mode, if we're currently stepping but have stopped in
5468 some other thread, we may need to switch back to the stepped
5469 thread. Returns true we set the inferior running, false if we left
5470 it stopped (and the event needs further processing). */
5473 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
5477 struct thread_info
*tp
;
5478 struct thread_info
*stepping_thread
;
5479 struct thread_info
*step_over
;
5481 /* If any thread is blocked on some internal breakpoint, and we
5482 simply need to step over that breakpoint to get it going
5483 again, do that first. */
5485 /* However, if we see an event for the stepping thread, then we
5486 know all other threads have been moved past their breakpoints
5487 already. Let the caller check whether the step is finished,
5488 etc., before deciding to move it past a breakpoint. */
5489 if (ecs
->event_thread
->control
.step_range_end
!= 0)
5492 /* Check if the current thread is blocked on an incomplete
5493 step-over, interrupted by a random signal. */
5494 if (ecs
->event_thread
->control
.trap_expected
5495 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5499 fprintf_unfiltered (gdb_stdlog
,
5500 "infrun: need to finish step-over of [%s]\n",
5501 target_pid_to_str (ecs
->event_thread
->ptid
));
5507 /* Check if the current thread is blocked by a single-step
5508 breakpoint of another thread. */
5509 if (ecs
->hit_singlestep_breakpoint
)
5513 fprintf_unfiltered (gdb_stdlog
,
5514 "infrun: need to step [%s] over single-step "
5516 target_pid_to_str (ecs
->ptid
));
5522 /* Otherwise, we no longer expect a trap in the current thread.
5523 Clear the trap_expected flag before switching back -- this is
5524 what keep_going does as well, if we call it. */
5525 ecs
->event_thread
->control
.trap_expected
= 0;
5527 /* Likewise, clear the signal if it should not be passed. */
5528 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5529 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5531 /* If scheduler locking applies even if not stepping, there's no
5532 need to walk over threads. Above we've checked whether the
5533 current thread is stepping. If some other thread not the
5534 event thread is stepping, then it must be that scheduler
5535 locking is not in effect. */
5536 if (schedlock_applies (0))
5539 /* Look for the stepping/nexting thread, and check if any other
5540 thread other than the stepping thread needs to start a
5541 step-over. Do all step-overs before actually proceeding with
5543 stepping_thread
= NULL
;
5545 ALL_NON_EXITED_THREADS (tp
)
5547 /* Ignore threads of processes we're not resuming. */
5549 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
5552 /* When stepping over a breakpoint, we lock all threads
5553 except the one that needs to move past the breakpoint.
5554 If a non-event thread has this set, the "incomplete
5555 step-over" check above should have caught it earlier. */
5556 gdb_assert (!tp
->control
.trap_expected
);
5558 /* Did we find the stepping thread? */
5559 if (tp
->control
.step_range_end
)
5561 /* Yep. There should only one though. */
5562 gdb_assert (stepping_thread
== NULL
);
5564 /* The event thread is handled at the top, before we
5566 gdb_assert (tp
!= ecs
->event_thread
);
5568 /* If some thread other than the event thread is
5569 stepping, then scheduler locking can't be in effect,
5570 otherwise we wouldn't have resumed the current event
5571 thread in the first place. */
5572 gdb_assert (!schedlock_applies (currently_stepping (tp
)));
5574 stepping_thread
= tp
;
5576 else if (thread_still_needs_step_over (tp
))
5580 /* At the top we've returned early if the event thread
5581 is stepping. If some other thread not the event
5582 thread is stepping, then scheduler locking can't be
5583 in effect, and we can resume this thread. No need to
5584 keep looking for the stepping thread then. */
5589 if (step_over
!= NULL
)
5594 fprintf_unfiltered (gdb_stdlog
,
5595 "infrun: need to step-over [%s]\n",
5596 target_pid_to_str (tp
->ptid
));
5599 /* Only the stepping thread should have this set. */
5600 gdb_assert (tp
->control
.step_range_end
== 0);
5602 ecs
->ptid
= tp
->ptid
;
5603 ecs
->event_thread
= tp
;
5604 switch_to_thread (ecs
->ptid
);
5609 if (stepping_thread
!= NULL
)
5611 struct frame_info
*frame
;
5612 struct gdbarch
*gdbarch
;
5614 tp
= stepping_thread
;
5616 /* If the stepping thread exited, then don't try to switch
5617 back and resume it, which could fail in several different
5618 ways depending on the target. Instead, just keep going.
5620 We can find a stepping dead thread in the thread list in
5623 - The target supports thread exit events, and when the
5624 target tries to delete the thread from the thread list,
5625 inferior_ptid pointed at the exiting thread. In such
5626 case, calling delete_thread does not really remove the
5627 thread from the list; instead, the thread is left listed,
5628 with 'exited' state.
5630 - The target's debug interface does not support thread
5631 exit events, and so we have no idea whatsoever if the
5632 previously stepping thread is still alive. For that
5633 reason, we need to synchronously query the target
5635 if (is_exited (tp
->ptid
)
5636 || !target_thread_alive (tp
->ptid
))
5639 fprintf_unfiltered (gdb_stdlog
,
5640 "infrun: not switching back to "
5641 "stepped thread, it has vanished\n");
5643 delete_thread (tp
->ptid
);
5649 fprintf_unfiltered (gdb_stdlog
,
5650 "infrun: switching back to stepped thread\n");
5652 ecs
->event_thread
= tp
;
5653 ecs
->ptid
= tp
->ptid
;
5654 context_switch (ecs
->ptid
);
5656 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5657 frame
= get_current_frame ();
5658 gdbarch
= get_frame_arch (frame
);
5660 /* If the PC of the thread we were trying to single-step has
5661 changed, then that thread has trapped or been signaled,
5662 but the event has not been reported to GDB yet. Re-poll
5663 the target looking for this particular thread's event
5664 (i.e. temporarily enable schedlock) by:
5666 - setting a break at the current PC
5667 - resuming that particular thread, only (by setting
5670 This prevents us continuously moving the single-step
5671 breakpoint forward, one instruction at a time,
5674 if (stop_pc
!= tp
->prev_pc
)
5677 fprintf_unfiltered (gdb_stdlog
,
5678 "infrun: expected thread advanced also\n");
5680 /* Clear the info of the previous step-over, as it's no
5681 longer valid. It's what keep_going would do too, if
5682 we called it. Must do this before trying to insert
5683 the sss breakpoint, otherwise if we were previously
5684 trying to step over this exact address in another
5685 thread, the breakpoint ends up not installed. */
5686 clear_step_over_info ();
5688 insert_single_step_breakpoint (get_frame_arch (frame
),
5689 get_frame_address_space (frame
),
5691 ecs
->event_thread
->control
.trap_expected
= 1;
5693 resume (0, GDB_SIGNAL_0
);
5694 prepare_to_wait (ecs
);
5699 fprintf_unfiltered (gdb_stdlog
,
5700 "infrun: expected thread still "
5701 "hasn't advanced\n");
5711 /* Is thread TP in the middle of single-stepping? */
5714 currently_stepping (struct thread_info
*tp
)
5716 return ((tp
->control
.step_range_end
5717 && tp
->control
.step_resume_breakpoint
== NULL
)
5718 || tp
->control
.trap_expected
5719 || tp
->stepped_breakpoint
5720 || bpstat_should_step ());
5723 /* Inferior has stepped into a subroutine call with source code that
5724 we should not step over. Do step to the first line of code in
5728 handle_step_into_function (struct gdbarch
*gdbarch
,
5729 struct execution_control_state
*ecs
)
5731 struct compunit_symtab
*cust
;
5732 struct symtab_and_line stop_func_sal
, sr_sal
;
5734 fill_in_stop_func (gdbarch
, ecs
);
5736 cust
= find_pc_compunit_symtab (stop_pc
);
5737 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
5738 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5739 ecs
->stop_func_start
);
5741 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5742 /* Use the step_resume_break to step until the end of the prologue,
5743 even if that involves jumps (as it seems to on the vax under
5745 /* If the prologue ends in the middle of a source line, continue to
5746 the end of that source line (if it is still within the function).
5747 Otherwise, just go to end of prologue. */
5748 if (stop_func_sal
.end
5749 && stop_func_sal
.pc
!= ecs
->stop_func_start
5750 && stop_func_sal
.end
< ecs
->stop_func_end
)
5751 ecs
->stop_func_start
= stop_func_sal
.end
;
5753 /* Architectures which require breakpoint adjustment might not be able
5754 to place a breakpoint at the computed address. If so, the test
5755 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5756 ecs->stop_func_start to an address at which a breakpoint may be
5757 legitimately placed.
5759 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5760 made, GDB will enter an infinite loop when stepping through
5761 optimized code consisting of VLIW instructions which contain
5762 subinstructions corresponding to different source lines. On
5763 FR-V, it's not permitted to place a breakpoint on any but the
5764 first subinstruction of a VLIW instruction. When a breakpoint is
5765 set, GDB will adjust the breakpoint address to the beginning of
5766 the VLIW instruction. Thus, we need to make the corresponding
5767 adjustment here when computing the stop address. */
5769 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5771 ecs
->stop_func_start
5772 = gdbarch_adjust_breakpoint_address (gdbarch
,
5773 ecs
->stop_func_start
);
5776 if (ecs
->stop_func_start
== stop_pc
)
5778 /* We are already there: stop now. */
5779 end_stepping_range (ecs
);
5784 /* Put the step-breakpoint there and go until there. */
5785 init_sal (&sr_sal
); /* initialize to zeroes */
5786 sr_sal
.pc
= ecs
->stop_func_start
;
5787 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5788 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5790 /* Do not specify what the fp should be when we stop since on
5791 some machines the prologue is where the new fp value is
5793 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5795 /* And make sure stepping stops right away then. */
5796 ecs
->event_thread
->control
.step_range_end
5797 = ecs
->event_thread
->control
.step_range_start
;
5802 /* Inferior has stepped backward into a subroutine call with source
5803 code that we should not step over. Do step to the beginning of the
5804 last line of code in it. */
5807 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5808 struct execution_control_state
*ecs
)
5810 struct compunit_symtab
*cust
;
5811 struct symtab_and_line stop_func_sal
;
5813 fill_in_stop_func (gdbarch
, ecs
);
5815 cust
= find_pc_compunit_symtab (stop_pc
);
5816 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
5817 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5818 ecs
->stop_func_start
);
5820 stop_func_sal
= find_pc_line (stop_pc
, 0);
5822 /* OK, we're just going to keep stepping here. */
5823 if (stop_func_sal
.pc
== stop_pc
)
5825 /* We're there already. Just stop stepping now. */
5826 end_stepping_range (ecs
);
5830 /* Else just reset the step range and keep going.
5831 No step-resume breakpoint, they don't work for
5832 epilogues, which can have multiple entry paths. */
5833 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5834 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5840 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5841 This is used to both functions and to skip over code. */
5844 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5845 struct symtab_and_line sr_sal
,
5846 struct frame_id sr_id
,
5847 enum bptype sr_type
)
5849 /* There should never be more than one step-resume or longjmp-resume
5850 breakpoint per thread, so we should never be setting a new
5851 step_resume_breakpoint when one is already active. */
5852 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5853 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5856 fprintf_unfiltered (gdb_stdlog
,
5857 "infrun: inserting step-resume breakpoint at %s\n",
5858 paddress (gdbarch
, sr_sal
.pc
));
5860 inferior_thread ()->control
.step_resume_breakpoint
5861 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5865 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5866 struct symtab_and_line sr_sal
,
5867 struct frame_id sr_id
)
5869 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5874 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5875 This is used to skip a potential signal handler.
5877 This is called with the interrupted function's frame. The signal
5878 handler, when it returns, will resume the interrupted function at
5882 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5884 struct symtab_and_line sr_sal
;
5885 struct gdbarch
*gdbarch
;
5887 gdb_assert (return_frame
!= NULL
);
5888 init_sal (&sr_sal
); /* initialize to zeros */
5890 gdbarch
= get_frame_arch (return_frame
);
5891 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5892 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5893 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5895 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5896 get_stack_frame_id (return_frame
),
5900 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5901 is used to skip a function after stepping into it (for "next" or if
5902 the called function has no debugging information).
5904 The current function has almost always been reached by single
5905 stepping a call or return instruction. NEXT_FRAME belongs to the
5906 current function, and the breakpoint will be set at the caller's
5909 This is a separate function rather than reusing
5910 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5911 get_prev_frame, which may stop prematurely (see the implementation
5912 of frame_unwind_caller_id for an example). */
5915 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5917 struct symtab_and_line sr_sal
;
5918 struct gdbarch
*gdbarch
;
5920 /* We shouldn't have gotten here if we don't know where the call site
5922 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5924 init_sal (&sr_sal
); /* initialize to zeros */
5926 gdbarch
= frame_unwind_caller_arch (next_frame
);
5927 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5928 frame_unwind_caller_pc (next_frame
));
5929 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5930 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5932 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5933 frame_unwind_caller_id (next_frame
));
5936 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5937 new breakpoint at the target of a jmp_buf. The handling of
5938 longjmp-resume uses the same mechanisms used for handling
5939 "step-resume" breakpoints. */
5942 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5944 /* There should never be more than one longjmp-resume breakpoint per
5945 thread, so we should never be setting a new
5946 longjmp_resume_breakpoint when one is already active. */
5947 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
5950 fprintf_unfiltered (gdb_stdlog
,
5951 "infrun: inserting longjmp-resume breakpoint at %s\n",
5952 paddress (gdbarch
, pc
));
5954 inferior_thread ()->control
.exception_resume_breakpoint
=
5955 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5958 /* Insert an exception resume breakpoint. TP is the thread throwing
5959 the exception. The block B is the block of the unwinder debug hook
5960 function. FRAME is the frame corresponding to the call to this
5961 function. SYM is the symbol of the function argument holding the
5962 target PC of the exception. */
5965 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5966 const struct block
*b
,
5967 struct frame_info
*frame
,
5970 volatile struct gdb_exception e
;
5972 /* We want to ignore errors here. */
5973 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5975 struct symbol
*vsym
;
5976 struct value
*value
;
5978 struct breakpoint
*bp
;
5980 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5981 value
= read_var_value (vsym
, frame
);
5982 /* If the value was optimized out, revert to the old behavior. */
5983 if (! value_optimized_out (value
))
5985 handler
= value_as_address (value
);
5988 fprintf_unfiltered (gdb_stdlog
,
5989 "infrun: exception resume at %lx\n",
5990 (unsigned long) handler
);
5992 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5993 handler
, bp_exception_resume
);
5995 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5998 bp
->thread
= tp
->num
;
5999 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
6004 /* A helper for check_exception_resume that sets an
6005 exception-breakpoint based on a SystemTap probe. */
6008 insert_exception_resume_from_probe (struct thread_info
*tp
,
6009 const struct bound_probe
*probe
,
6010 struct frame_info
*frame
)
6012 struct value
*arg_value
;
6014 struct breakpoint
*bp
;
6016 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
6020 handler
= value_as_address (arg_value
);
6023 fprintf_unfiltered (gdb_stdlog
,
6024 "infrun: exception resume at %s\n",
6025 paddress (get_objfile_arch (probe
->objfile
),
6028 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
6029 handler
, bp_exception_resume
);
6030 bp
->thread
= tp
->num
;
6031 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
6034 /* This is called when an exception has been intercepted. Check to
6035 see whether the exception's destination is of interest, and if so,
6036 set an exception resume breakpoint there. */
6039 check_exception_resume (struct execution_control_state
*ecs
,
6040 struct frame_info
*frame
)
6042 volatile struct gdb_exception e
;
6043 struct bound_probe probe
;
6044 struct symbol
*func
;
6046 /* First see if this exception unwinding breakpoint was set via a
6047 SystemTap probe point. If so, the probe has two arguments: the
6048 CFA and the HANDLER. We ignore the CFA, extract the handler, and
6049 set a breakpoint there. */
6050 probe
= find_probe_by_pc (get_frame_pc (frame
));
6053 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
6057 func
= get_frame_function (frame
);
6061 TRY_CATCH (e
, RETURN_MASK_ERROR
)
6063 const struct block
*b
;
6064 struct block_iterator iter
;
6068 /* The exception breakpoint is a thread-specific breakpoint on
6069 the unwinder's debug hook, declared as:
6071 void _Unwind_DebugHook (void *cfa, void *handler);
6073 The CFA argument indicates the frame to which control is
6074 about to be transferred. HANDLER is the destination PC.
6076 We ignore the CFA and set a temporary breakpoint at HANDLER.
6077 This is not extremely efficient but it avoids issues in gdb
6078 with computing the DWARF CFA, and it also works even in weird
6079 cases such as throwing an exception from inside a signal
6082 b
= SYMBOL_BLOCK_VALUE (func
);
6083 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
6085 if (!SYMBOL_IS_ARGUMENT (sym
))
6092 insert_exception_resume_breakpoint (ecs
->event_thread
,
6101 stop_waiting (struct execution_control_state
*ecs
)
6104 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
6106 clear_step_over_info ();
6108 /* Let callers know we don't want to wait for the inferior anymore. */
6109 ecs
->wait_some_more
= 0;
6112 /* Called when we should continue running the inferior, because the
6113 current event doesn't cause a user visible stop. This does the
6114 resuming part; waiting for the next event is done elsewhere. */
6117 keep_going (struct execution_control_state
*ecs
)
6119 /* Make sure normal_stop is called if we get a QUIT handled before
6121 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
6123 /* Save the pc before execution, to compare with pc after stop. */
6124 ecs
->event_thread
->prev_pc
6125 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
6127 if (ecs
->event_thread
->control
.trap_expected
6128 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6130 /* We haven't yet gotten our trap, and either: intercepted a
6131 non-signal event (e.g., a fork); or took a signal which we
6132 are supposed to pass through to the inferior. Simply
6134 discard_cleanups (old_cleanups
);
6135 resume (currently_stepping (ecs
->event_thread
),
6136 ecs
->event_thread
->suspend
.stop_signal
);
6140 volatile struct gdb_exception e
;
6141 struct regcache
*regcache
= get_current_regcache ();
6145 /* Either the trap was not expected, but we are continuing
6146 anyway (if we got a signal, the user asked it be passed to
6149 We got our expected trap, but decided we should resume from
6152 We're going to run this baby now!
6154 Note that insert_breakpoints won't try to re-insert
6155 already inserted breakpoints. Therefore, we don't
6156 care if breakpoints were already inserted, or not. */
6158 /* If we need to step over a breakpoint, and we're not using
6159 displaced stepping to do so, insert all breakpoints
6160 (watchpoints, etc.) but the one we're stepping over, step one
6161 instruction, and then re-insert the breakpoint when that step
6164 remove_bp
= (ecs
->hit_singlestep_breakpoint
6165 || thread_still_needs_step_over (ecs
->event_thread
));
6166 remove_wps
= (ecs
->event_thread
->stepping_over_watchpoint
6167 && !target_have_steppable_watchpoint
);
6169 if (remove_bp
&& !use_displaced_stepping (get_regcache_arch (regcache
)))
6171 set_step_over_info (get_regcache_aspace (regcache
),
6172 regcache_read_pc (regcache
), remove_wps
);
6174 else if (remove_wps
)
6175 set_step_over_info (NULL
, 0, remove_wps
);
6177 clear_step_over_info ();
6179 /* Stop stepping if inserting breakpoints fails. */
6180 TRY_CATCH (e
, RETURN_MASK_ERROR
)
6182 insert_breakpoints ();
6186 exception_print (gdb_stderr
, e
);
6191 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
6193 /* Do not deliver GDB_SIGNAL_TRAP (except when the user
6194 explicitly specifies that such a signal should be delivered
6195 to the target program). Typically, that would occur when a
6196 user is debugging a target monitor on a simulator: the target
6197 monitor sets a breakpoint; the simulator encounters this
6198 breakpoint and halts the simulation handing control to GDB;
6199 GDB, noting that the stop address doesn't map to any known
6200 breakpoint, returns control back to the simulator; the
6201 simulator then delivers the hardware equivalent of a
6202 GDB_SIGNAL_TRAP to the program being debugged. */
6203 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6204 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6205 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6207 discard_cleanups (old_cleanups
);
6208 resume (currently_stepping (ecs
->event_thread
),
6209 ecs
->event_thread
->suspend
.stop_signal
);
6212 prepare_to_wait (ecs
);
6215 /* This function normally comes after a resume, before
6216 handle_inferior_event exits. It takes care of any last bits of
6217 housekeeping, and sets the all-important wait_some_more flag. */
6220 prepare_to_wait (struct execution_control_state
*ecs
)
6223 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
6225 /* This is the old end of the while loop. Let everybody know we
6226 want to wait for the inferior some more and get called again
6228 ecs
->wait_some_more
= 1;
6231 /* We are done with the step range of a step/next/si/ni command.
6232 Called once for each n of a "step n" operation. */
6235 end_stepping_range (struct execution_control_state
*ecs
)
6237 ecs
->event_thread
->control
.stop_step
= 1;
6241 /* Several print_*_reason functions to print why the inferior has stopped.
6242 We always print something when the inferior exits, or receives a signal.
6243 The rest of the cases are dealt with later on in normal_stop and
6244 print_it_typical. Ideally there should be a call to one of these
6245 print_*_reason functions functions from handle_inferior_event each time
6246 stop_waiting is called.
6248 Note that we don't call these directly, instead we delegate that to
6249 the interpreters, through observers. Interpreters then call these
6250 with whatever uiout is right. */
6253 print_end_stepping_range_reason (struct ui_out
*uiout
)
6255 /* For CLI-like interpreters, print nothing. */
6257 if (ui_out_is_mi_like_p (uiout
))
6259 ui_out_field_string (uiout
, "reason",
6260 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
6265 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6267 annotate_signalled ();
6268 if (ui_out_is_mi_like_p (uiout
))
6270 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
6271 ui_out_text (uiout
, "\nProgram terminated with signal ");
6272 annotate_signal_name ();
6273 ui_out_field_string (uiout
, "signal-name",
6274 gdb_signal_to_name (siggnal
));
6275 annotate_signal_name_end ();
6276 ui_out_text (uiout
, ", ");
6277 annotate_signal_string ();
6278 ui_out_field_string (uiout
, "signal-meaning",
6279 gdb_signal_to_string (siggnal
));
6280 annotate_signal_string_end ();
6281 ui_out_text (uiout
, ".\n");
6282 ui_out_text (uiout
, "The program no longer exists.\n");
6286 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
6288 struct inferior
*inf
= current_inferior ();
6289 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
6291 annotate_exited (exitstatus
);
6294 if (ui_out_is_mi_like_p (uiout
))
6295 ui_out_field_string (uiout
, "reason",
6296 async_reason_lookup (EXEC_ASYNC_EXITED
));
6297 ui_out_text (uiout
, "[Inferior ");
6298 ui_out_text (uiout
, plongest (inf
->num
));
6299 ui_out_text (uiout
, " (");
6300 ui_out_text (uiout
, pidstr
);
6301 ui_out_text (uiout
, ") exited with code ");
6302 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
6303 ui_out_text (uiout
, "]\n");
6307 if (ui_out_is_mi_like_p (uiout
))
6309 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
6310 ui_out_text (uiout
, "[Inferior ");
6311 ui_out_text (uiout
, plongest (inf
->num
));
6312 ui_out_text (uiout
, " (");
6313 ui_out_text (uiout
, pidstr
);
6314 ui_out_text (uiout
, ") exited normally]\n");
6319 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6323 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
6325 struct thread_info
*t
= inferior_thread ();
6327 ui_out_text (uiout
, "\n[");
6328 ui_out_field_string (uiout
, "thread-name",
6329 target_pid_to_str (t
->ptid
));
6330 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
6331 ui_out_text (uiout
, " stopped");
6335 ui_out_text (uiout
, "\nProgram received signal ");
6336 annotate_signal_name ();
6337 if (ui_out_is_mi_like_p (uiout
))
6339 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
6340 ui_out_field_string (uiout
, "signal-name",
6341 gdb_signal_to_name (siggnal
));
6342 annotate_signal_name_end ();
6343 ui_out_text (uiout
, ", ");
6344 annotate_signal_string ();
6345 ui_out_field_string (uiout
, "signal-meaning",
6346 gdb_signal_to_string (siggnal
));
6347 annotate_signal_string_end ();
6349 ui_out_text (uiout
, ".\n");
6353 print_no_history_reason (struct ui_out
*uiout
)
6355 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
6358 /* Print current location without a level number, if we have changed
6359 functions or hit a breakpoint. Print source line if we have one.
6360 bpstat_print contains the logic deciding in detail what to print,
6361 based on the event(s) that just occurred. */
6364 print_stop_event (struct target_waitstatus
*ws
)
6368 int do_frame_printing
= 1;
6369 struct thread_info
*tp
= inferior_thread ();
6371 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
6375 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
6376 should) carry around the function and does (or should) use
6377 that when doing a frame comparison. */
6378 if (tp
->control
.stop_step
6379 && frame_id_eq (tp
->control
.step_frame_id
,
6380 get_frame_id (get_current_frame ()))
6381 && step_start_function
== find_pc_function (stop_pc
))
6383 /* Finished step, just print source line. */
6384 source_flag
= SRC_LINE
;
6388 /* Print location and source line. */
6389 source_flag
= SRC_AND_LOC
;
6392 case PRINT_SRC_AND_LOC
:
6393 /* Print location and source line. */
6394 source_flag
= SRC_AND_LOC
;
6396 case PRINT_SRC_ONLY
:
6397 source_flag
= SRC_LINE
;
6400 /* Something bogus. */
6401 source_flag
= SRC_LINE
;
6402 do_frame_printing
= 0;
6405 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6408 /* The behavior of this routine with respect to the source
6410 SRC_LINE: Print only source line
6411 LOCATION: Print only location
6412 SRC_AND_LOC: Print location and source line. */
6413 if (do_frame_printing
)
6414 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
6416 /* Display the auto-display expressions. */
6420 /* Here to return control to GDB when the inferior stops for real.
6421 Print appropriate messages, remove breakpoints, give terminal our modes.
6423 STOP_PRINT_FRAME nonzero means print the executing frame
6424 (pc, function, args, file, line number and line text).
6425 BREAKPOINTS_FAILED nonzero means stop was due to error
6426 attempting to insert breakpoints. */
6431 struct target_waitstatus last
;
6433 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
6435 get_last_target_status (&last_ptid
, &last
);
6437 /* If an exception is thrown from this point on, make sure to
6438 propagate GDB's knowledge of the executing state to the
6439 frontend/user running state. A QUIT is an easy exception to see
6440 here, so do this before any filtered output. */
6442 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
6443 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6444 && last
.kind
!= TARGET_WAITKIND_EXITED
6445 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6446 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
6448 /* As we're presenting a stop, and potentially removing breakpoints,
6449 update the thread list so we can tell whether there are threads
6450 running on the target. With target remote, for example, we can
6451 only learn about new threads when we explicitly update the thread
6452 list. Do this before notifying the interpreters about signal
6453 stops, end of stepping ranges, etc., so that the "new thread"
6454 output is emitted before e.g., "Program received signal FOO",
6455 instead of after. */
6456 update_thread_list ();
6458 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
6459 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
6461 /* As with the notification of thread events, we want to delay
6462 notifying the user that we've switched thread context until
6463 the inferior actually stops.
6465 There's no point in saying anything if the inferior has exited.
6466 Note that SIGNALLED here means "exited with a signal", not
6467 "received a signal".
6469 Also skip saying anything in non-stop mode. In that mode, as we
6470 don't want GDB to switch threads behind the user's back, to avoid
6471 races where the user is typing a command to apply to thread x,
6472 but GDB switches to thread y before the user finishes entering
6473 the command, fetch_inferior_event installs a cleanup to restore
6474 the current thread back to the thread the user had selected right
6475 after this event is handled, so we're not really switching, only
6476 informing of a stop. */
6478 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
6479 && target_has_execution
6480 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6481 && last
.kind
!= TARGET_WAITKIND_EXITED
6482 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6484 target_terminal_ours_for_output ();
6485 printf_filtered (_("[Switching to %s]\n"),
6486 target_pid_to_str (inferior_ptid
));
6487 annotate_thread_changed ();
6488 previous_inferior_ptid
= inferior_ptid
;
6491 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
6493 gdb_assert (sync_execution
|| !target_can_async_p ());
6495 target_terminal_ours_for_output ();
6496 printf_filtered (_("No unwaited-for children left.\n"));
6499 /* Note: this depends on the update_thread_list call above. */
6500 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
6502 if (remove_breakpoints ())
6504 target_terminal_ours_for_output ();
6505 printf_filtered (_("Cannot remove breakpoints because "
6506 "program is no longer writable.\nFurther "
6507 "execution is probably impossible.\n"));
6511 /* If an auto-display called a function and that got a signal,
6512 delete that auto-display to avoid an infinite recursion. */
6514 if (stopped_by_random_signal
)
6515 disable_current_display ();
6517 /* Notify observers if we finished a "step"-like command, etc. */
6518 if (target_has_execution
6519 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6520 && last
.kind
!= TARGET_WAITKIND_EXITED
6521 && inferior_thread ()->control
.stop_step
)
6523 /* But not if in the middle of doing a "step n" operation for
6525 if (inferior_thread ()->step_multi
)
6528 observer_notify_end_stepping_range ();
6531 target_terminal_ours ();
6532 async_enable_stdin ();
6534 /* Set the current source location. This will also happen if we
6535 display the frame below, but the current SAL will be incorrect
6536 during a user hook-stop function. */
6537 if (has_stack_frames () && !stop_stack_dummy
)
6538 set_current_sal_from_frame (get_current_frame ());
6540 /* Let the user/frontend see the threads as stopped, but do nothing
6541 if the thread was running an infcall. We may be e.g., evaluating
6542 a breakpoint condition. In that case, the thread had state
6543 THREAD_RUNNING before the infcall, and shall remain set to
6544 running, all without informing the user/frontend about state
6545 transition changes. If this is actually a call command, then the
6546 thread was originally already stopped, so there's no state to
6548 if (target_has_execution
&& inferior_thread ()->control
.in_infcall
)
6549 discard_cleanups (old_chain
);
6551 do_cleanups (old_chain
);
6553 /* Look up the hook_stop and run it (CLI internally handles problem
6554 of stop_command's pre-hook not existing). */
6556 catch_errors (hook_stop_stub
, stop_command
,
6557 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6559 if (!has_stack_frames ())
6562 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6563 || last
.kind
== TARGET_WAITKIND_EXITED
)
6566 /* Select innermost stack frame - i.e., current frame is frame 0,
6567 and current location is based on that.
6568 Don't do this on return from a stack dummy routine,
6569 or if the program has exited. */
6571 if (!stop_stack_dummy
)
6573 select_frame (get_current_frame ());
6575 /* If --batch-silent is enabled then there's no need to print the current
6576 source location, and to try risks causing an error message about
6577 missing source files. */
6578 if (stop_print_frame
&& !batch_silent
)
6579 print_stop_event (&last
);
6582 /* Save the function value return registers, if we care.
6583 We might be about to restore their previous contents. */
6584 if (inferior_thread ()->control
.proceed_to_finish
6585 && execution_direction
!= EXEC_REVERSE
)
6587 /* This should not be necessary. */
6589 regcache_xfree (stop_registers
);
6591 /* NB: The copy goes through to the target picking up the value of
6592 all the registers. */
6593 stop_registers
= regcache_dup (get_current_regcache ());
6596 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6598 /* Pop the empty frame that contains the stack dummy.
6599 This also restores inferior state prior to the call
6600 (struct infcall_suspend_state). */
6601 struct frame_info
*frame
= get_current_frame ();
6603 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6605 /* frame_pop() calls reinit_frame_cache as the last thing it
6606 does which means there's currently no selected frame. We
6607 don't need to re-establish a selected frame if the dummy call
6608 returns normally, that will be done by
6609 restore_infcall_control_state. However, we do have to handle
6610 the case where the dummy call is returning after being
6611 stopped (e.g. the dummy call previously hit a breakpoint).
6612 We can't know which case we have so just always re-establish
6613 a selected frame here. */
6614 select_frame (get_current_frame ());
6618 annotate_stopped ();
6620 /* Suppress the stop observer if we're in the middle of:
6622 - a step n (n > 1), as there still more steps to be done.
6624 - a "finish" command, as the observer will be called in
6625 finish_command_continuation, so it can include the inferior
6626 function's return value.
6628 - calling an inferior function, as we pretend we inferior didn't
6629 run at all. The return value of the call is handled by the
6630 expression evaluator, through call_function_by_hand. */
6632 if (!target_has_execution
6633 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6634 || last
.kind
== TARGET_WAITKIND_EXITED
6635 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6636 || (!(inferior_thread ()->step_multi
6637 && inferior_thread ()->control
.stop_step
)
6638 && !(inferior_thread ()->control
.stop_bpstat
6639 && inferior_thread ()->control
.proceed_to_finish
)
6640 && !inferior_thread ()->control
.in_infcall
))
6642 if (!ptid_equal (inferior_ptid
, null_ptid
))
6643 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6646 observer_notify_normal_stop (NULL
, stop_print_frame
);
6649 if (target_has_execution
)
6651 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6652 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6653 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6654 Delete any breakpoint that is to be deleted at the next stop. */
6655 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6658 /* Try to get rid of automatically added inferiors that are no
6659 longer needed. Keeping those around slows down things linearly.
6660 Note that this never removes the current inferior. */
6665 hook_stop_stub (void *cmd
)
6667 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6672 signal_stop_state (int signo
)
6674 return signal_stop
[signo
];
6678 signal_print_state (int signo
)
6680 return signal_print
[signo
];
6684 signal_pass_state (int signo
)
6686 return signal_program
[signo
];
6690 signal_cache_update (int signo
)
6694 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6695 signal_cache_update (signo
);
6700 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6701 && signal_print
[signo
] == 0
6702 && signal_program
[signo
] == 1
6703 && signal_catch
[signo
] == 0);
6707 signal_stop_update (int signo
, int state
)
6709 int ret
= signal_stop
[signo
];
6711 signal_stop
[signo
] = state
;
6712 signal_cache_update (signo
);
6717 signal_print_update (int signo
, int state
)
6719 int ret
= signal_print
[signo
];
6721 signal_print
[signo
] = state
;
6722 signal_cache_update (signo
);
6727 signal_pass_update (int signo
, int state
)
6729 int ret
= signal_program
[signo
];
6731 signal_program
[signo
] = state
;
6732 signal_cache_update (signo
);
6736 /* Update the global 'signal_catch' from INFO and notify the
6740 signal_catch_update (const unsigned int *info
)
6744 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
6745 signal_catch
[i
] = info
[i
] > 0;
6746 signal_cache_update (-1);
6747 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6751 sig_print_header (void)
6753 printf_filtered (_("Signal Stop\tPrint\tPass "
6754 "to program\tDescription\n"));
6758 sig_print_info (enum gdb_signal oursig
)
6760 const char *name
= gdb_signal_to_name (oursig
);
6761 int name_padding
= 13 - strlen (name
);
6763 if (name_padding
<= 0)
6766 printf_filtered ("%s", name
);
6767 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6768 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6769 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6770 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6771 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6774 /* Specify how various signals in the inferior should be handled. */
6777 handle_command (char *args
, int from_tty
)
6780 int digits
, wordlen
;
6781 int sigfirst
, signum
, siglast
;
6782 enum gdb_signal oursig
;
6785 unsigned char *sigs
;
6786 struct cleanup
*old_chain
;
6790 error_no_arg (_("signal to handle"));
6793 /* Allocate and zero an array of flags for which signals to handle. */
6795 nsigs
= (int) GDB_SIGNAL_LAST
;
6796 sigs
= (unsigned char *) alloca (nsigs
);
6797 memset (sigs
, 0, nsigs
);
6799 /* Break the command line up into args. */
6801 argv
= gdb_buildargv (args
);
6802 old_chain
= make_cleanup_freeargv (argv
);
6804 /* Walk through the args, looking for signal oursigs, signal names, and
6805 actions. Signal numbers and signal names may be interspersed with
6806 actions, with the actions being performed for all signals cumulatively
6807 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6809 while (*argv
!= NULL
)
6811 wordlen
= strlen (*argv
);
6812 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6816 sigfirst
= siglast
= -1;
6818 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6820 /* Apply action to all signals except those used by the
6821 debugger. Silently skip those. */
6824 siglast
= nsigs
- 1;
6826 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6828 SET_SIGS (nsigs
, sigs
, signal_stop
);
6829 SET_SIGS (nsigs
, sigs
, signal_print
);
6831 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6833 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6835 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6837 SET_SIGS (nsigs
, sigs
, signal_print
);
6839 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6841 SET_SIGS (nsigs
, sigs
, signal_program
);
6843 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6845 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6847 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6849 SET_SIGS (nsigs
, sigs
, signal_program
);
6851 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6853 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6854 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6856 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6858 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6860 else if (digits
> 0)
6862 /* It is numeric. The numeric signal refers to our own
6863 internal signal numbering from target.h, not to host/target
6864 signal number. This is a feature; users really should be
6865 using symbolic names anyway, and the common ones like
6866 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6868 sigfirst
= siglast
= (int)
6869 gdb_signal_from_command (atoi (*argv
));
6870 if ((*argv
)[digits
] == '-')
6873 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6875 if (sigfirst
> siglast
)
6877 /* Bet he didn't figure we'd think of this case... */
6885 oursig
= gdb_signal_from_name (*argv
);
6886 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6888 sigfirst
= siglast
= (int) oursig
;
6892 /* Not a number and not a recognized flag word => complain. */
6893 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6897 /* If any signal numbers or symbol names were found, set flags for
6898 which signals to apply actions to. */
6900 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6902 switch ((enum gdb_signal
) signum
)
6904 case GDB_SIGNAL_TRAP
:
6905 case GDB_SIGNAL_INT
:
6906 if (!allsigs
&& !sigs
[signum
])
6908 if (query (_("%s is used by the debugger.\n\
6909 Are you sure you want to change it? "),
6910 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6916 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6917 gdb_flush (gdb_stdout
);
6922 case GDB_SIGNAL_DEFAULT
:
6923 case GDB_SIGNAL_UNKNOWN
:
6924 /* Make sure that "all" doesn't print these. */
6935 for (signum
= 0; signum
< nsigs
; signum
++)
6938 signal_cache_update (-1);
6939 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6940 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6944 /* Show the results. */
6945 sig_print_header ();
6946 for (; signum
< nsigs
; signum
++)
6948 sig_print_info (signum
);
6954 do_cleanups (old_chain
);
6957 /* Complete the "handle" command. */
6959 static VEC (char_ptr
) *
6960 handle_completer (struct cmd_list_element
*ignore
,
6961 const char *text
, const char *word
)
6963 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
6964 static const char * const keywords
[] =
6978 vec_signals
= signal_completer (ignore
, text
, word
);
6979 vec_keywords
= complete_on_enum (keywords
, word
, word
);
6981 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
6982 VEC_free (char_ptr
, vec_signals
);
6983 VEC_free (char_ptr
, vec_keywords
);
6988 xdb_handle_command (char *args
, int from_tty
)
6991 struct cleanup
*old_chain
;
6994 error_no_arg (_("xdb command"));
6996 /* Break the command line up into args. */
6998 argv
= gdb_buildargv (args
);
6999 old_chain
= make_cleanup_freeargv (argv
);
7000 if (argv
[1] != (char *) NULL
)
7005 bufLen
= strlen (argv
[0]) + 20;
7006 argBuf
= (char *) xmalloc (bufLen
);
7010 enum gdb_signal oursig
;
7012 oursig
= gdb_signal_from_name (argv
[0]);
7013 memset (argBuf
, 0, bufLen
);
7014 if (strcmp (argv
[1], "Q") == 0)
7015 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
7018 if (strcmp (argv
[1], "s") == 0)
7020 if (!signal_stop
[oursig
])
7021 sprintf (argBuf
, "%s %s", argv
[0], "stop");
7023 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
7025 else if (strcmp (argv
[1], "i") == 0)
7027 if (!signal_program
[oursig
])
7028 sprintf (argBuf
, "%s %s", argv
[0], "pass");
7030 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
7032 else if (strcmp (argv
[1], "r") == 0)
7034 if (!signal_print
[oursig
])
7035 sprintf (argBuf
, "%s %s", argv
[0], "print");
7037 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
7043 handle_command (argBuf
, from_tty
);
7045 printf_filtered (_("Invalid signal handling flag.\n"));
7050 do_cleanups (old_chain
);
7054 gdb_signal_from_command (int num
)
7056 if (num
>= 1 && num
<= 15)
7057 return (enum gdb_signal
) num
;
7058 error (_("Only signals 1-15 are valid as numeric signals.\n\
7059 Use \"info signals\" for a list of symbolic signals."));
7062 /* Print current contents of the tables set by the handle command.
7063 It is possible we should just be printing signals actually used
7064 by the current target (but for things to work right when switching
7065 targets, all signals should be in the signal tables). */
7068 signals_info (char *signum_exp
, int from_tty
)
7070 enum gdb_signal oursig
;
7072 sig_print_header ();
7076 /* First see if this is a symbol name. */
7077 oursig
= gdb_signal_from_name (signum_exp
);
7078 if (oursig
== GDB_SIGNAL_UNKNOWN
)
7080 /* No, try numeric. */
7082 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
7084 sig_print_info (oursig
);
7088 printf_filtered ("\n");
7089 /* These ugly casts brought to you by the native VAX compiler. */
7090 for (oursig
= GDB_SIGNAL_FIRST
;
7091 (int) oursig
< (int) GDB_SIGNAL_LAST
;
7092 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
7096 if (oursig
!= GDB_SIGNAL_UNKNOWN
7097 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
7098 sig_print_info (oursig
);
7101 printf_filtered (_("\nUse the \"handle\" command "
7102 "to change these tables.\n"));
7105 /* Check if it makes sense to read $_siginfo from the current thread
7106 at this point. If not, throw an error. */
7109 validate_siginfo_access (void)
7111 /* No current inferior, no siginfo. */
7112 if (ptid_equal (inferior_ptid
, null_ptid
))
7113 error (_("No thread selected."));
7115 /* Don't try to read from a dead thread. */
7116 if (is_exited (inferior_ptid
))
7117 error (_("The current thread has terminated"));
7119 /* ... or from a spinning thread. */
7120 if (is_running (inferior_ptid
))
7121 error (_("Selected thread is running."));
7124 /* The $_siginfo convenience variable is a bit special. We don't know
7125 for sure the type of the value until we actually have a chance to
7126 fetch the data. The type can change depending on gdbarch, so it is
7127 also dependent on which thread you have selected.
7129 1. making $_siginfo be an internalvar that creates a new value on
7132 2. making the value of $_siginfo be an lval_computed value. */
7134 /* This function implements the lval_computed support for reading a
7138 siginfo_value_read (struct value
*v
)
7140 LONGEST transferred
;
7142 validate_siginfo_access ();
7145 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
7147 value_contents_all_raw (v
),
7149 TYPE_LENGTH (value_type (v
)));
7151 if (transferred
!= TYPE_LENGTH (value_type (v
)))
7152 error (_("Unable to read siginfo"));
7155 /* This function implements the lval_computed support for writing a
7159 siginfo_value_write (struct value
*v
, struct value
*fromval
)
7161 LONGEST transferred
;
7163 validate_siginfo_access ();
7165 transferred
= target_write (¤t_target
,
7166 TARGET_OBJECT_SIGNAL_INFO
,
7168 value_contents_all_raw (fromval
),
7170 TYPE_LENGTH (value_type (fromval
)));
7172 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
7173 error (_("Unable to write siginfo"));
7176 static const struct lval_funcs siginfo_value_funcs
=
7182 /* Return a new value with the correct type for the siginfo object of
7183 the current thread using architecture GDBARCH. Return a void value
7184 if there's no object available. */
7186 static struct value
*
7187 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
7190 if (target_has_stack
7191 && !ptid_equal (inferior_ptid
, null_ptid
)
7192 && gdbarch_get_siginfo_type_p (gdbarch
))
7194 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7196 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
7199 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
7203 /* infcall_suspend_state contains state about the program itself like its
7204 registers and any signal it received when it last stopped.
7205 This state must be restored regardless of how the inferior function call
7206 ends (either successfully, or after it hits a breakpoint or signal)
7207 if the program is to properly continue where it left off. */
7209 struct infcall_suspend_state
7211 struct thread_suspend_state thread_suspend
;
7212 #if 0 /* Currently unused and empty structures are not valid C. */
7213 struct inferior_suspend_state inferior_suspend
;
7218 struct regcache
*registers
;
7220 /* Format of SIGINFO_DATA or NULL if it is not present. */
7221 struct gdbarch
*siginfo_gdbarch
;
7223 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
7224 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
7225 content would be invalid. */
7226 gdb_byte
*siginfo_data
;
7229 struct infcall_suspend_state
*
7230 save_infcall_suspend_state (void)
7232 struct infcall_suspend_state
*inf_state
;
7233 struct thread_info
*tp
= inferior_thread ();
7235 struct inferior
*inf
= current_inferior ();
7237 struct regcache
*regcache
= get_current_regcache ();
7238 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7239 gdb_byte
*siginfo_data
= NULL
;
7241 if (gdbarch_get_siginfo_type_p (gdbarch
))
7243 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7244 size_t len
= TYPE_LENGTH (type
);
7245 struct cleanup
*back_to
;
7247 siginfo_data
= xmalloc (len
);
7248 back_to
= make_cleanup (xfree
, siginfo_data
);
7250 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7251 siginfo_data
, 0, len
) == len
)
7252 discard_cleanups (back_to
);
7255 /* Errors ignored. */
7256 do_cleanups (back_to
);
7257 siginfo_data
= NULL
;
7261 inf_state
= XCNEW (struct infcall_suspend_state
);
7265 inf_state
->siginfo_gdbarch
= gdbarch
;
7266 inf_state
->siginfo_data
= siginfo_data
;
7269 inf_state
->thread_suspend
= tp
->suspend
;
7270 #if 0 /* Currently unused and empty structures are not valid C. */
7271 inf_state
->inferior_suspend
= inf
->suspend
;
7274 /* run_inferior_call will not use the signal due to its `proceed' call with
7275 GDB_SIGNAL_0 anyway. */
7276 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7278 inf_state
->stop_pc
= stop_pc
;
7280 inf_state
->registers
= regcache_dup (regcache
);
7285 /* Restore inferior session state to INF_STATE. */
7288 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7290 struct thread_info
*tp
= inferior_thread ();
7292 struct inferior
*inf
= current_inferior ();
7294 struct regcache
*regcache
= get_current_regcache ();
7295 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7297 tp
->suspend
= inf_state
->thread_suspend
;
7298 #if 0 /* Currently unused and empty structures are not valid C. */
7299 inf
->suspend
= inf_state
->inferior_suspend
;
7302 stop_pc
= inf_state
->stop_pc
;
7304 if (inf_state
->siginfo_gdbarch
== gdbarch
)
7306 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7308 /* Errors ignored. */
7309 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7310 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
7313 /* The inferior can be gone if the user types "print exit(0)"
7314 (and perhaps other times). */
7315 if (target_has_execution
)
7316 /* NB: The register write goes through to the target. */
7317 regcache_cpy (regcache
, inf_state
->registers
);
7319 discard_infcall_suspend_state (inf_state
);
7323 do_restore_infcall_suspend_state_cleanup (void *state
)
7325 restore_infcall_suspend_state (state
);
7329 make_cleanup_restore_infcall_suspend_state
7330 (struct infcall_suspend_state
*inf_state
)
7332 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
7336 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7338 regcache_xfree (inf_state
->registers
);
7339 xfree (inf_state
->siginfo_data
);
7344 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
7346 return inf_state
->registers
;
7349 /* infcall_control_state contains state regarding gdb's control of the
7350 inferior itself like stepping control. It also contains session state like
7351 the user's currently selected frame. */
7353 struct infcall_control_state
7355 struct thread_control_state thread_control
;
7356 struct inferior_control_state inferior_control
;
7359 enum stop_stack_kind stop_stack_dummy
;
7360 int stopped_by_random_signal
;
7361 int stop_after_trap
;
7363 /* ID if the selected frame when the inferior function call was made. */
7364 struct frame_id selected_frame_id
;
7367 /* Save all of the information associated with the inferior<==>gdb
7370 struct infcall_control_state
*
7371 save_infcall_control_state (void)
7373 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
7374 struct thread_info
*tp
= inferior_thread ();
7375 struct inferior
*inf
= current_inferior ();
7377 inf_status
->thread_control
= tp
->control
;
7378 inf_status
->inferior_control
= inf
->control
;
7380 tp
->control
.step_resume_breakpoint
= NULL
;
7381 tp
->control
.exception_resume_breakpoint
= NULL
;
7383 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
7384 chain. If caller's caller is walking the chain, they'll be happier if we
7385 hand them back the original chain when restore_infcall_control_state is
7387 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
7390 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
7391 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
7392 inf_status
->stop_after_trap
= stop_after_trap
;
7394 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
7400 restore_selected_frame (void *args
)
7402 struct frame_id
*fid
= (struct frame_id
*) args
;
7403 struct frame_info
*frame
;
7405 frame
= frame_find_by_id (*fid
);
7407 /* If inf_status->selected_frame_id is NULL, there was no previously
7411 warning (_("Unable to restore previously selected frame."));
7415 select_frame (frame
);
7420 /* Restore inferior session state to INF_STATUS. */
7423 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
7425 struct thread_info
*tp
= inferior_thread ();
7426 struct inferior
*inf
= current_inferior ();
7428 if (tp
->control
.step_resume_breakpoint
)
7429 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
7431 if (tp
->control
.exception_resume_breakpoint
)
7432 tp
->control
.exception_resume_breakpoint
->disposition
7433 = disp_del_at_next_stop
;
7435 /* Handle the bpstat_copy of the chain. */
7436 bpstat_clear (&tp
->control
.stop_bpstat
);
7438 tp
->control
= inf_status
->thread_control
;
7439 inf
->control
= inf_status
->inferior_control
;
7442 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
7443 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
7444 stop_after_trap
= inf_status
->stop_after_trap
;
7446 if (target_has_stack
)
7448 /* The point of catch_errors is that if the stack is clobbered,
7449 walking the stack might encounter a garbage pointer and
7450 error() trying to dereference it. */
7452 (restore_selected_frame
, &inf_status
->selected_frame_id
,
7453 "Unable to restore previously selected frame:\n",
7454 RETURN_MASK_ERROR
) == 0)
7455 /* Error in restoring the selected frame. Select the innermost
7457 select_frame (get_current_frame ());
7464 do_restore_infcall_control_state_cleanup (void *sts
)
7466 restore_infcall_control_state (sts
);
7470 make_cleanup_restore_infcall_control_state
7471 (struct infcall_control_state
*inf_status
)
7473 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
7477 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
7479 if (inf_status
->thread_control
.step_resume_breakpoint
)
7480 inf_status
->thread_control
.step_resume_breakpoint
->disposition
7481 = disp_del_at_next_stop
;
7483 if (inf_status
->thread_control
.exception_resume_breakpoint
)
7484 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
7485 = disp_del_at_next_stop
;
7487 /* See save_infcall_control_state for info on stop_bpstat. */
7488 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
7493 /* restore_inferior_ptid() will be used by the cleanup machinery
7494 to restore the inferior_ptid value saved in a call to
7495 save_inferior_ptid(). */
7498 restore_inferior_ptid (void *arg
)
7500 ptid_t
*saved_ptid_ptr
= arg
;
7502 inferior_ptid
= *saved_ptid_ptr
;
7506 /* Save the value of inferior_ptid so that it may be restored by a
7507 later call to do_cleanups(). Returns the struct cleanup pointer
7508 needed for later doing the cleanup. */
7511 save_inferior_ptid (void)
7513 ptid_t
*saved_ptid_ptr
;
7515 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
7516 *saved_ptid_ptr
= inferior_ptid
;
7517 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
7523 clear_exit_convenience_vars (void)
7525 clear_internalvar (lookup_internalvar ("_exitsignal"));
7526 clear_internalvar (lookup_internalvar ("_exitcode"));
7530 /* User interface for reverse debugging:
7531 Set exec-direction / show exec-direction commands
7532 (returns error unless target implements to_set_exec_direction method). */
7534 int execution_direction
= EXEC_FORWARD
;
7535 static const char exec_forward
[] = "forward";
7536 static const char exec_reverse
[] = "reverse";
7537 static const char *exec_direction
= exec_forward
;
7538 static const char *const exec_direction_names
[] = {
7545 set_exec_direction_func (char *args
, int from_tty
,
7546 struct cmd_list_element
*cmd
)
7548 if (target_can_execute_reverse
)
7550 if (!strcmp (exec_direction
, exec_forward
))
7551 execution_direction
= EXEC_FORWARD
;
7552 else if (!strcmp (exec_direction
, exec_reverse
))
7553 execution_direction
= EXEC_REVERSE
;
7557 exec_direction
= exec_forward
;
7558 error (_("Target does not support this operation."));
7563 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7564 struct cmd_list_element
*cmd
, const char *value
)
7566 switch (execution_direction
) {
7568 fprintf_filtered (out
, _("Forward.\n"));
7571 fprintf_filtered (out
, _("Reverse.\n"));
7574 internal_error (__FILE__
, __LINE__
,
7575 _("bogus execution_direction value: %d"),
7576 (int) execution_direction
);
7581 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7582 struct cmd_list_element
*c
, const char *value
)
7584 fprintf_filtered (file
, _("Resuming the execution of threads "
7585 "of all processes is %s.\n"), value
);
7588 /* Implementation of `siginfo' variable. */
7590 static const struct internalvar_funcs siginfo_funcs
=
7598 _initialize_infrun (void)
7602 struct cmd_list_element
*c
;
7604 add_info ("signals", signals_info
, _("\
7605 What debugger does when program gets various signals.\n\
7606 Specify a signal as argument to print info on that signal only."));
7607 add_info_alias ("handle", "signals", 0);
7609 c
= add_com ("handle", class_run
, handle_command
, _("\
7610 Specify how to handle signals.\n\
7611 Usage: handle SIGNAL [ACTIONS]\n\
7612 Args are signals and actions to apply to those signals.\n\
7613 If no actions are specified, the current settings for the specified signals\n\
7614 will be displayed instead.\n\
7616 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7617 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7618 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7619 The special arg \"all\" is recognized to mean all signals except those\n\
7620 used by the debugger, typically SIGTRAP and SIGINT.\n\
7622 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7623 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7624 Stop means reenter debugger if this signal happens (implies print).\n\
7625 Print means print a message if this signal happens.\n\
7626 Pass means let program see this signal; otherwise program doesn't know.\n\
7627 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7628 Pass and Stop may be combined.\n\
7630 Multiple signals may be specified. Signal numbers and signal names\n\
7631 may be interspersed with actions, with the actions being performed for\n\
7632 all signals cumulatively specified."));
7633 set_cmd_completer (c
, handle_completer
);
7637 add_com ("lz", class_info
, signals_info
, _("\
7638 What debugger does when program gets various signals.\n\
7639 Specify a signal as argument to print info on that signal only."));
7640 add_com ("z", class_run
, xdb_handle_command
, _("\
7641 Specify how to handle a signal.\n\
7642 Args are signals and actions to apply to those signals.\n\
7643 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7644 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7645 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7646 The special arg \"all\" is recognized to mean all signals except those\n\
7647 used by the debugger, typically SIGTRAP and SIGINT.\n\
7648 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7649 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7650 nopass), \"Q\" (noprint)\n\
7651 Stop means reenter debugger if this signal happens (implies print).\n\
7652 Print means print a message if this signal happens.\n\
7653 Pass means let program see this signal; otherwise program doesn't know.\n\
7654 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7655 Pass and Stop may be combined."));
7659 stop_command
= add_cmd ("stop", class_obscure
,
7660 not_just_help_class_command
, _("\
7661 There is no `stop' command, but you can set a hook on `stop'.\n\
7662 This allows you to set a list of commands to be run each time execution\n\
7663 of the program stops."), &cmdlist
);
7665 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7666 Set inferior debugging."), _("\
7667 Show inferior debugging."), _("\
7668 When non-zero, inferior specific debugging is enabled."),
7671 &setdebuglist
, &showdebuglist
);
7673 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7674 &debug_displaced
, _("\
7675 Set displaced stepping debugging."), _("\
7676 Show displaced stepping debugging."), _("\
7677 When non-zero, displaced stepping specific debugging is enabled."),
7679 show_debug_displaced
,
7680 &setdebuglist
, &showdebuglist
);
7682 add_setshow_boolean_cmd ("non-stop", no_class
,
7684 Set whether gdb controls the inferior in non-stop mode."), _("\
7685 Show whether gdb controls the inferior in non-stop mode."), _("\
7686 When debugging a multi-threaded program and this setting is\n\
7687 off (the default, also called all-stop mode), when one thread stops\n\
7688 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7689 all other threads in the program while you interact with the thread of\n\
7690 interest. When you continue or step a thread, you can allow the other\n\
7691 threads to run, or have them remain stopped, but while you inspect any\n\
7692 thread's state, all threads stop.\n\
7694 In non-stop mode, when one thread stops, other threads can continue\n\
7695 to run freely. You'll be able to step each thread independently,\n\
7696 leave it stopped or free to run as needed."),
7702 numsigs
= (int) GDB_SIGNAL_LAST
;
7703 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7704 signal_print
= (unsigned char *)
7705 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7706 signal_program
= (unsigned char *)
7707 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7708 signal_catch
= (unsigned char *)
7709 xmalloc (sizeof (signal_catch
[0]) * numsigs
);
7710 signal_pass
= (unsigned char *)
7711 xmalloc (sizeof (signal_pass
[0]) * numsigs
);
7712 for (i
= 0; i
< numsigs
; i
++)
7715 signal_print
[i
] = 1;
7716 signal_program
[i
] = 1;
7717 signal_catch
[i
] = 0;
7720 /* Signals caused by debugger's own actions
7721 should not be given to the program afterwards. */
7722 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7723 signal_program
[GDB_SIGNAL_INT
] = 0;
7725 /* Signals that are not errors should not normally enter the debugger. */
7726 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7727 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7728 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7729 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7730 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7731 signal_print
[GDB_SIGNAL_PROF
] = 0;
7732 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7733 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7734 signal_stop
[GDB_SIGNAL_IO
] = 0;
7735 signal_print
[GDB_SIGNAL_IO
] = 0;
7736 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7737 signal_print
[GDB_SIGNAL_POLL
] = 0;
7738 signal_stop
[GDB_SIGNAL_URG
] = 0;
7739 signal_print
[GDB_SIGNAL_URG
] = 0;
7740 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7741 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7742 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7743 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7745 /* These signals are used internally by user-level thread
7746 implementations. (See signal(5) on Solaris.) Like the above
7747 signals, a healthy program receives and handles them as part of
7748 its normal operation. */
7749 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7750 signal_print
[GDB_SIGNAL_LWP
] = 0;
7751 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7752 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7753 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7754 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7756 /* Update cached state. */
7757 signal_cache_update (-1);
7759 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7760 &stop_on_solib_events
, _("\
7761 Set stopping for shared library events."), _("\
7762 Show stopping for shared library events."), _("\
7763 If nonzero, gdb will give control to the user when the dynamic linker\n\
7764 notifies gdb of shared library events. The most common event of interest\n\
7765 to the user would be loading/unloading of a new library."),
7766 set_stop_on_solib_events
,
7767 show_stop_on_solib_events
,
7768 &setlist
, &showlist
);
7770 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7771 follow_fork_mode_kind_names
,
7772 &follow_fork_mode_string
, _("\
7773 Set debugger response to a program call of fork or vfork."), _("\
7774 Show debugger response to a program call of fork or vfork."), _("\
7775 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7776 parent - the original process is debugged after a fork\n\
7777 child - the new process is debugged after a fork\n\
7778 The unfollowed process will continue to run.\n\
7779 By default, the debugger will follow the parent process."),
7781 show_follow_fork_mode_string
,
7782 &setlist
, &showlist
);
7784 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7785 follow_exec_mode_names
,
7786 &follow_exec_mode_string
, _("\
7787 Set debugger response to a program call of exec."), _("\
7788 Show debugger response to a program call of exec."), _("\
7789 An exec call replaces the program image of a process.\n\
7791 follow-exec-mode can be:\n\
7793 new - the debugger creates a new inferior and rebinds the process\n\
7794 to this new inferior. The program the process was running before\n\
7795 the exec call can be restarted afterwards by restarting the original\n\
7798 same - the debugger keeps the process bound to the same inferior.\n\
7799 The new executable image replaces the previous executable loaded in\n\
7800 the inferior. Restarting the inferior after the exec call restarts\n\
7801 the executable the process was running after the exec call.\n\
7803 By default, the debugger will use the same inferior."),
7805 show_follow_exec_mode_string
,
7806 &setlist
, &showlist
);
7808 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7809 scheduler_enums
, &scheduler_mode
, _("\
7810 Set mode for locking scheduler during execution."), _("\
7811 Show mode for locking scheduler during execution."), _("\
7812 off == no locking (threads may preempt at any time)\n\
7813 on == full locking (no thread except the current thread may run)\n\
7814 step == scheduler locked during every single-step operation.\n\
7815 In this mode, no other thread may run during a step command.\n\
7816 Other threads may run while stepping over a function call ('next')."),
7817 set_schedlock_func
, /* traps on target vector */
7818 show_scheduler_mode
,
7819 &setlist
, &showlist
);
7821 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7822 Set mode for resuming threads of all processes."), _("\
7823 Show mode for resuming threads of all processes."), _("\
7824 When on, execution commands (such as 'continue' or 'next') resume all\n\
7825 threads of all processes. When off (which is the default), execution\n\
7826 commands only resume the threads of the current process. The set of\n\
7827 threads that are resumed is further refined by the scheduler-locking\n\
7828 mode (see help set scheduler-locking)."),
7830 show_schedule_multiple
,
7831 &setlist
, &showlist
);
7833 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7834 Set mode of the step operation."), _("\
7835 Show mode of the step operation."), _("\
7836 When set, doing a step over a function without debug line information\n\
7837 will stop at the first instruction of that function. Otherwise, the\n\
7838 function is skipped and the step command stops at a different source line."),
7840 show_step_stop_if_no_debug
,
7841 &setlist
, &showlist
);
7843 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7844 &can_use_displaced_stepping
, _("\
7845 Set debugger's willingness to use displaced stepping."), _("\
7846 Show debugger's willingness to use displaced stepping."), _("\
7847 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7848 supported by the target architecture. If off, gdb will not use displaced\n\
7849 stepping to step over breakpoints, even if such is supported by the target\n\
7850 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7851 if the target architecture supports it and non-stop mode is active, but will not\n\
7852 use it in all-stop mode (see help set non-stop)."),
7854 show_can_use_displaced_stepping
,
7855 &setlist
, &showlist
);
7857 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7858 &exec_direction
, _("Set direction of execution.\n\
7859 Options are 'forward' or 'reverse'."),
7860 _("Show direction of execution (forward/reverse)."),
7861 _("Tells gdb whether to execute forward or backward."),
7862 set_exec_direction_func
, show_exec_direction_func
,
7863 &setlist
, &showlist
);
7865 /* Set/show detach-on-fork: user-settable mode. */
7867 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7868 Set whether gdb will detach the child of a fork."), _("\
7869 Show whether gdb will detach the child of a fork."), _("\
7870 Tells gdb whether to detach the child of a fork."),
7871 NULL
, NULL
, &setlist
, &showlist
);
7873 /* Set/show disable address space randomization mode. */
7875 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7876 &disable_randomization
, _("\
7877 Set disabling of debuggee's virtual address space randomization."), _("\
7878 Show disabling of debuggee's virtual address space randomization."), _("\
7879 When this mode is on (which is the default), randomization of the virtual\n\
7880 address space is disabled. Standalone programs run with the randomization\n\
7881 enabled by default on some platforms."),
7882 &set_disable_randomization
,
7883 &show_disable_randomization
,
7884 &setlist
, &showlist
);
7886 /* ptid initializations */
7887 inferior_ptid
= null_ptid
;
7888 target_last_wait_ptid
= minus_one_ptid
;
7890 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7891 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7892 observer_attach_thread_exit (infrun_thread_thread_exit
);
7893 observer_attach_inferior_exit (infrun_inferior_exit
);
7895 /* Explicitly create without lookup, since that tries to create a
7896 value with a void typed value, and when we get here, gdbarch
7897 isn't initialized yet. At this point, we're quite sure there
7898 isn't another convenience variable of the same name. */
7899 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7901 add_setshow_boolean_cmd ("observer", no_class
,
7902 &observer_mode_1
, _("\
7903 Set whether gdb controls the inferior in observer mode."), _("\
7904 Show whether gdb controls the inferior in observer mode."), _("\
7905 In observer mode, GDB can get data from the inferior, but not\n\
7906 affect its execution. Registers and memory may not be changed,\n\
7907 breakpoints may not be set, and the program cannot be interrupted\n\