1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2014 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 /* Prototypes for local functions */
66 static void signals_info (char *, int);
68 static void handle_command (char *, int);
70 static void sig_print_info (enum gdb_signal
);
72 static void sig_print_header (void);
74 static void resume_cleanups (void *);
76 static int hook_stop_stub (void *);
78 static int restore_selected_frame (void *);
80 static int follow_fork (void);
82 static int follow_fork_inferior (int follow_child
, int detach_fork
);
84 static void follow_inferior_reset_breakpoints (void);
86 static void set_schedlock_func (char *args
, int from_tty
,
87 struct cmd_list_element
*c
);
89 static int currently_stepping (struct thread_info
*tp
);
91 static void xdb_handle_command (char *args
, int from_tty
);
93 void _initialize_infrun (void);
95 void nullify_last_target_wait_ptid (void);
97 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
99 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
101 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
103 /* When set, stop the 'step' command if we enter a function which has
104 no line number information. The normal behavior is that we step
105 over such function. */
106 int step_stop_if_no_debug
= 0;
108 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
109 struct cmd_list_element
*c
, const char *value
)
111 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
114 /* In asynchronous mode, but simulating synchronous execution. */
116 int sync_execution
= 0;
118 /* proceed and normal_stop use this to notify the user when the
119 inferior stopped in a different thread than it had been running
122 static ptid_t previous_inferior_ptid
;
124 /* If set (default for legacy reasons), when following a fork, GDB
125 will detach from one of the fork branches, child or parent.
126 Exactly which branch is detached depends on 'set follow-fork-mode'
129 static int detach_fork
= 1;
131 int debug_displaced
= 0;
133 show_debug_displaced (struct ui_file
*file
, int from_tty
,
134 struct cmd_list_element
*c
, const char *value
)
136 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
139 unsigned int debug_infrun
= 0;
141 show_debug_infrun (struct ui_file
*file
, int from_tty
,
142 struct cmd_list_element
*c
, const char *value
)
144 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
148 /* Support for disabling address space randomization. */
150 int disable_randomization
= 1;
153 show_disable_randomization (struct ui_file
*file
, int from_tty
,
154 struct cmd_list_element
*c
, const char *value
)
156 if (target_supports_disable_randomization ())
157 fprintf_filtered (file
,
158 _("Disabling randomization of debuggee's "
159 "virtual address space is %s.\n"),
162 fputs_filtered (_("Disabling randomization of debuggee's "
163 "virtual address space is unsupported on\n"
164 "this platform.\n"), file
);
168 set_disable_randomization (char *args
, int from_tty
,
169 struct cmd_list_element
*c
)
171 if (!target_supports_disable_randomization ())
172 error (_("Disabling randomization of debuggee's "
173 "virtual address space is unsupported on\n"
177 /* User interface for non-stop mode. */
180 static int non_stop_1
= 0;
183 set_non_stop (char *args
, int from_tty
,
184 struct cmd_list_element
*c
)
186 if (target_has_execution
)
188 non_stop_1
= non_stop
;
189 error (_("Cannot change this setting while the inferior is running."));
192 non_stop
= non_stop_1
;
196 show_non_stop (struct ui_file
*file
, int from_tty
,
197 struct cmd_list_element
*c
, const char *value
)
199 fprintf_filtered (file
,
200 _("Controlling the inferior in non-stop mode is %s.\n"),
204 /* "Observer mode" is somewhat like a more extreme version of
205 non-stop, in which all GDB operations that might affect the
206 target's execution have been disabled. */
208 int observer_mode
= 0;
209 static int observer_mode_1
= 0;
212 set_observer_mode (char *args
, int from_tty
,
213 struct cmd_list_element
*c
)
215 if (target_has_execution
)
217 observer_mode_1
= observer_mode
;
218 error (_("Cannot change this setting while the inferior is running."));
221 observer_mode
= observer_mode_1
;
223 may_write_registers
= !observer_mode
;
224 may_write_memory
= !observer_mode
;
225 may_insert_breakpoints
= !observer_mode
;
226 may_insert_tracepoints
= !observer_mode
;
227 /* We can insert fast tracepoints in or out of observer mode,
228 but enable them if we're going into this mode. */
230 may_insert_fast_tracepoints
= 1;
231 may_stop
= !observer_mode
;
232 update_target_permissions ();
234 /* Going *into* observer mode we must force non-stop, then
235 going out we leave it that way. */
238 pagination_enabled
= 0;
239 non_stop
= non_stop_1
= 1;
243 printf_filtered (_("Observer mode is now %s.\n"),
244 (observer_mode
? "on" : "off"));
248 show_observer_mode (struct ui_file
*file
, int from_tty
,
249 struct cmd_list_element
*c
, const char *value
)
251 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
254 /* This updates the value of observer mode based on changes in
255 permissions. Note that we are deliberately ignoring the values of
256 may-write-registers and may-write-memory, since the user may have
257 reason to enable these during a session, for instance to turn on a
258 debugging-related global. */
261 update_observer_mode (void)
265 newval
= (!may_insert_breakpoints
266 && !may_insert_tracepoints
267 && may_insert_fast_tracepoints
271 /* Let the user know if things change. */
272 if (newval
!= observer_mode
)
273 printf_filtered (_("Observer mode is now %s.\n"),
274 (newval
? "on" : "off"));
276 observer_mode
= observer_mode_1
= newval
;
279 /* Tables of how to react to signals; the user sets them. */
281 static unsigned char *signal_stop
;
282 static unsigned char *signal_print
;
283 static unsigned char *signal_program
;
285 /* Table of signals that are registered with "catch signal". A
286 non-zero entry indicates that the signal is caught by some "catch
287 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
289 static unsigned char *signal_catch
;
291 /* Table of signals that the target may silently handle.
292 This is automatically determined from the flags above,
293 and simply cached here. */
294 static unsigned char *signal_pass
;
296 #define SET_SIGS(nsigs,sigs,flags) \
298 int signum = (nsigs); \
299 while (signum-- > 0) \
300 if ((sigs)[signum]) \
301 (flags)[signum] = 1; \
304 #define UNSET_SIGS(nsigs,sigs,flags) \
306 int signum = (nsigs); \
307 while (signum-- > 0) \
308 if ((sigs)[signum]) \
309 (flags)[signum] = 0; \
312 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
313 this function is to avoid exporting `signal_program'. */
316 update_signals_program_target (void)
318 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
321 /* Value to pass to target_resume() to cause all threads to resume. */
323 #define RESUME_ALL minus_one_ptid
325 /* Command list pointer for the "stop" placeholder. */
327 static struct cmd_list_element
*stop_command
;
329 /* Function inferior was in as of last step command. */
331 static struct symbol
*step_start_function
;
333 /* Nonzero if we want to give control to the user when we're notified
334 of shared library events by the dynamic linker. */
335 int stop_on_solib_events
;
337 /* Enable or disable optional shared library event breakpoints
338 as appropriate when the above flag is changed. */
341 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
343 update_solib_breakpoints ();
347 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
348 struct cmd_list_element
*c
, const char *value
)
350 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
354 /* Nonzero means expecting a trace trap
355 and should stop the inferior and return silently when it happens. */
359 /* Save register contents here when executing a "finish" command or are
360 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
361 Thus this contains the return value from the called function (assuming
362 values are returned in a register). */
364 struct regcache
*stop_registers
;
366 /* Nonzero after stop if current stack frame should be printed. */
368 static int stop_print_frame
;
370 /* This is a cached copy of the pid/waitstatus of the last event
371 returned by target_wait()/deprecated_target_wait_hook(). This
372 information is returned by get_last_target_status(). */
373 static ptid_t target_last_wait_ptid
;
374 static struct target_waitstatus target_last_waitstatus
;
376 static void context_switch (ptid_t ptid
);
378 void init_thread_stepping_state (struct thread_info
*tss
);
380 static const char follow_fork_mode_child
[] = "child";
381 static const char follow_fork_mode_parent
[] = "parent";
383 static const char *const follow_fork_mode_kind_names
[] = {
384 follow_fork_mode_child
,
385 follow_fork_mode_parent
,
389 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
391 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
392 struct cmd_list_element
*c
, const char *value
)
394 fprintf_filtered (file
,
395 _("Debugger response to a program "
396 "call of fork or vfork is \"%s\".\n"),
401 /* Handle changes to the inferior list based on the type of fork,
402 which process is being followed, and whether the other process
403 should be detached. On entry inferior_ptid must be the ptid of
404 the fork parent. At return inferior_ptid is the ptid of the
405 followed inferior. */
408 follow_fork_inferior (int follow_child
, int detach_fork
)
411 int parent_pid
, child_pid
;
413 has_vforked
= (inferior_thread ()->pending_follow
.kind
414 == TARGET_WAITKIND_VFORKED
);
415 parent_pid
= ptid_get_lwp (inferior_ptid
);
417 parent_pid
= ptid_get_pid (inferior_ptid
);
419 = ptid_get_pid (inferior_thread ()->pending_follow
.value
.related_pid
);
422 && !non_stop
/* Non-stop always resumes both branches. */
423 && (!target_is_async_p () || sync_execution
)
424 && !(follow_child
|| detach_fork
|| sched_multi
))
426 /* The parent stays blocked inside the vfork syscall until the
427 child execs or exits. If we don't let the child run, then
428 the parent stays blocked. If we're telling the parent to run
429 in the foreground, the user will not be able to ctrl-c to get
430 back the terminal, effectively hanging the debug session. */
431 fprintf_filtered (gdb_stderr
, _("\
432 Can not resume the parent process over vfork in the foreground while\n\
433 holding the child stopped. Try \"set detach-on-fork\" or \
434 \"set schedule-multiple\".\n"));
435 /* FIXME output string > 80 columns. */
441 /* Detach new forked process? */
444 struct cleanup
*old_chain
;
446 /* Before detaching from the child, remove all breakpoints
447 from it. If we forked, then this has already been taken
448 care of by infrun.c. If we vforked however, any
449 breakpoint inserted in the parent is visible in the
450 child, even those added while stopped in a vfork
451 catchpoint. This will remove the breakpoints from the
452 parent also, but they'll be reinserted below. */
455 /* Keep breakpoints list in sync. */
456 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
459 if (info_verbose
|| debug_infrun
)
461 target_terminal_ours_for_output ();
462 fprintf_filtered (gdb_stdlog
,
463 _("Detaching after %s from "
464 "child process %d.\n"),
465 has_vforked
? "vfork" : "fork",
471 struct inferior
*parent_inf
, *child_inf
;
472 struct cleanup
*old_chain
;
474 /* Add process to GDB's tables. */
475 child_inf
= add_inferior (child_pid
);
477 parent_inf
= current_inferior ();
478 child_inf
->attach_flag
= parent_inf
->attach_flag
;
479 copy_terminal_info (child_inf
, parent_inf
);
480 child_inf
->gdbarch
= parent_inf
->gdbarch
;
481 copy_inferior_target_desc_info (child_inf
, parent_inf
);
483 old_chain
= save_inferior_ptid ();
484 save_current_program_space ();
486 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
487 add_thread (inferior_ptid
);
488 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
490 /* If this is a vfork child, then the address-space is
491 shared with the parent. */
494 child_inf
->pspace
= parent_inf
->pspace
;
495 child_inf
->aspace
= parent_inf
->aspace
;
497 /* The parent will be frozen until the child is done
498 with the shared region. Keep track of the
500 child_inf
->vfork_parent
= parent_inf
;
501 child_inf
->pending_detach
= 0;
502 parent_inf
->vfork_child
= child_inf
;
503 parent_inf
->pending_detach
= 0;
507 child_inf
->aspace
= new_address_space ();
508 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
509 child_inf
->removable
= 1;
510 set_current_program_space (child_inf
->pspace
);
511 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
513 /* Let the shared library layer (e.g., solib-svr4) learn
514 about this new process, relocate the cloned exec, pull
515 in shared libraries, and install the solib event
516 breakpoint. If a "cloned-VM" event was propagated
517 better throughout the core, this wouldn't be
519 solib_create_inferior_hook (0);
522 do_cleanups (old_chain
);
527 struct inferior
*parent_inf
;
529 parent_inf
= current_inferior ();
531 /* If we detached from the child, then we have to be careful
532 to not insert breakpoints in the parent until the child
533 is done with the shared memory region. However, if we're
534 staying attached to the child, then we can and should
535 insert breakpoints, so that we can debug it. A
536 subsequent child exec or exit is enough to know when does
537 the child stops using the parent's address space. */
538 parent_inf
->waiting_for_vfork_done
= detach_fork
;
539 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
544 /* Follow the child. */
545 struct inferior
*parent_inf
, *child_inf
;
546 struct program_space
*parent_pspace
;
548 if (info_verbose
|| debug_infrun
)
550 target_terminal_ours_for_output ();
551 fprintf_filtered (gdb_stdlog
,
552 _("Attaching after process %d "
553 "%s to child process %d.\n"),
555 has_vforked
? "vfork" : "fork",
559 /* Add the new inferior first, so that the target_detach below
560 doesn't unpush the target. */
562 child_inf
= add_inferior (child_pid
);
564 parent_inf
= current_inferior ();
565 child_inf
->attach_flag
= parent_inf
->attach_flag
;
566 copy_terminal_info (child_inf
, parent_inf
);
567 child_inf
->gdbarch
= parent_inf
->gdbarch
;
568 copy_inferior_target_desc_info (child_inf
, parent_inf
);
570 parent_pspace
= parent_inf
->pspace
;
572 /* If we're vforking, we want to hold on to the parent until the
573 child exits or execs. At child exec or exit time we can
574 remove the old breakpoints from the parent and detach or
575 resume debugging it. Otherwise, detach the parent now; we'll
576 want to reuse it's program/address spaces, but we can't set
577 them to the child before removing breakpoints from the
578 parent, otherwise, the breakpoints module could decide to
579 remove breakpoints from the wrong process (since they'd be
580 assigned to the same address space). */
584 gdb_assert (child_inf
->vfork_parent
== NULL
);
585 gdb_assert (parent_inf
->vfork_child
== NULL
);
586 child_inf
->vfork_parent
= parent_inf
;
587 child_inf
->pending_detach
= 0;
588 parent_inf
->vfork_child
= child_inf
;
589 parent_inf
->pending_detach
= detach_fork
;
590 parent_inf
->waiting_for_vfork_done
= 0;
592 else if (detach_fork
)
594 if (info_verbose
|| debug_infrun
)
596 target_terminal_ours_for_output ();
597 fprintf_filtered (gdb_stdlog
,
598 _("Detaching after fork from "
599 "child process %d.\n"),
603 target_detach (NULL
, 0);
606 /* Note that the detach above makes PARENT_INF dangling. */
608 /* Add the child thread to the appropriate lists, and switch to
609 this new thread, before cloning the program space, and
610 informing the solib layer about this new process. */
612 inferior_ptid
= ptid_build (child_pid
, child_pid
, 0);
613 add_thread (inferior_ptid
);
615 /* If this is a vfork child, then the address-space is shared
616 with the parent. If we detached from the parent, then we can
617 reuse the parent's program/address spaces. */
618 if (has_vforked
|| detach_fork
)
620 child_inf
->pspace
= parent_pspace
;
621 child_inf
->aspace
= child_inf
->pspace
->aspace
;
625 child_inf
->aspace
= new_address_space ();
626 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
627 child_inf
->removable
= 1;
628 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
629 set_current_program_space (child_inf
->pspace
);
630 clone_program_space (child_inf
->pspace
, parent_pspace
);
632 /* Let the shared library layer (e.g., solib-svr4) learn
633 about this new process, relocate the cloned exec, pull in
634 shared libraries, and install the solib event breakpoint.
635 If a "cloned-VM" event was propagated better throughout
636 the core, this wouldn't be required. */
637 solib_create_inferior_hook (0);
641 return target_follow_fork (follow_child
, detach_fork
);
644 /* Tell the target to follow the fork we're stopped at. Returns true
645 if the inferior should be resumed; false, if the target for some
646 reason decided it's best not to resume. */
651 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
652 int should_resume
= 1;
653 struct thread_info
*tp
;
655 /* Copy user stepping state to the new inferior thread. FIXME: the
656 followed fork child thread should have a copy of most of the
657 parent thread structure's run control related fields, not just these.
658 Initialized to avoid "may be used uninitialized" warnings from gcc. */
659 struct breakpoint
*step_resume_breakpoint
= NULL
;
660 struct breakpoint
*exception_resume_breakpoint
= NULL
;
661 CORE_ADDR step_range_start
= 0;
662 CORE_ADDR step_range_end
= 0;
663 struct frame_id step_frame_id
= { 0 };
664 struct interp
*command_interp
= NULL
;
669 struct target_waitstatus wait_status
;
671 /* Get the last target status returned by target_wait(). */
672 get_last_target_status (&wait_ptid
, &wait_status
);
674 /* If not stopped at a fork event, then there's nothing else to
676 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
677 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
680 /* Check if we switched over from WAIT_PTID, since the event was
682 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
683 && !ptid_equal (inferior_ptid
, wait_ptid
))
685 /* We did. Switch back to WAIT_PTID thread, to tell the
686 target to follow it (in either direction). We'll
687 afterwards refuse to resume, and inform the user what
689 switch_to_thread (wait_ptid
);
694 tp
= inferior_thread ();
696 /* If there were any forks/vforks that were caught and are now to be
697 followed, then do so now. */
698 switch (tp
->pending_follow
.kind
)
700 case TARGET_WAITKIND_FORKED
:
701 case TARGET_WAITKIND_VFORKED
:
703 ptid_t parent
, child
;
705 /* If the user did a next/step, etc, over a fork call,
706 preserve the stepping state in the fork child. */
707 if (follow_child
&& should_resume
)
709 step_resume_breakpoint
= clone_momentary_breakpoint
710 (tp
->control
.step_resume_breakpoint
);
711 step_range_start
= tp
->control
.step_range_start
;
712 step_range_end
= tp
->control
.step_range_end
;
713 step_frame_id
= tp
->control
.step_frame_id
;
714 exception_resume_breakpoint
715 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
716 command_interp
= tp
->control
.command_interp
;
718 /* For now, delete the parent's sr breakpoint, otherwise,
719 parent/child sr breakpoints are considered duplicates,
720 and the child version will not be installed. Remove
721 this when the breakpoints module becomes aware of
722 inferiors and address spaces. */
723 delete_step_resume_breakpoint (tp
);
724 tp
->control
.step_range_start
= 0;
725 tp
->control
.step_range_end
= 0;
726 tp
->control
.step_frame_id
= null_frame_id
;
727 delete_exception_resume_breakpoint (tp
);
728 tp
->control
.command_interp
= NULL
;
731 parent
= inferior_ptid
;
732 child
= tp
->pending_follow
.value
.related_pid
;
734 /* Set up inferior(s) as specified by the caller, and tell the
735 target to do whatever is necessary to follow either parent
737 if (follow_fork_inferior (follow_child
, detach_fork
))
739 /* Target refused to follow, or there's some other reason
740 we shouldn't resume. */
745 /* This pending follow fork event is now handled, one way
746 or another. The previous selected thread may be gone
747 from the lists by now, but if it is still around, need
748 to clear the pending follow request. */
749 tp
= find_thread_ptid (parent
);
751 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
753 /* This makes sure we don't try to apply the "Switched
754 over from WAIT_PID" logic above. */
755 nullify_last_target_wait_ptid ();
757 /* If we followed the child, switch to it... */
760 switch_to_thread (child
);
762 /* ... and preserve the stepping state, in case the
763 user was stepping over the fork call. */
766 tp
= inferior_thread ();
767 tp
->control
.step_resume_breakpoint
768 = step_resume_breakpoint
;
769 tp
->control
.step_range_start
= step_range_start
;
770 tp
->control
.step_range_end
= step_range_end
;
771 tp
->control
.step_frame_id
= step_frame_id
;
772 tp
->control
.exception_resume_breakpoint
773 = exception_resume_breakpoint
;
774 tp
->control
.command_interp
= command_interp
;
778 /* If we get here, it was because we're trying to
779 resume from a fork catchpoint, but, the user
780 has switched threads away from the thread that
781 forked. In that case, the resume command
782 issued is most likely not applicable to the
783 child, so just warn, and refuse to resume. */
784 warning (_("Not resuming: switched threads "
785 "before following fork child.\n"));
788 /* Reset breakpoints in the child as appropriate. */
789 follow_inferior_reset_breakpoints ();
792 switch_to_thread (parent
);
796 case TARGET_WAITKIND_SPURIOUS
:
797 /* Nothing to follow. */
800 internal_error (__FILE__
, __LINE__
,
801 "Unexpected pending_follow.kind %d\n",
802 tp
->pending_follow
.kind
);
806 return should_resume
;
810 follow_inferior_reset_breakpoints (void)
812 struct thread_info
*tp
= inferior_thread ();
814 /* Was there a step_resume breakpoint? (There was if the user
815 did a "next" at the fork() call.) If so, explicitly reset its
816 thread number. Cloned step_resume breakpoints are disabled on
817 creation, so enable it here now that it is associated with the
820 step_resumes are a form of bp that are made to be per-thread.
821 Since we created the step_resume bp when the parent process
822 was being debugged, and now are switching to the child process,
823 from the breakpoint package's viewpoint, that's a switch of
824 "threads". We must update the bp's notion of which thread
825 it is for, or it'll be ignored when it triggers. */
827 if (tp
->control
.step_resume_breakpoint
)
829 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
830 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
833 /* Treat exception_resume breakpoints like step_resume breakpoints. */
834 if (tp
->control
.exception_resume_breakpoint
)
836 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
837 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
840 /* Reinsert all breakpoints in the child. The user may have set
841 breakpoints after catching the fork, in which case those
842 were never set in the child, but only in the parent. This makes
843 sure the inserted breakpoints match the breakpoint list. */
845 breakpoint_re_set ();
846 insert_breakpoints ();
849 /* The child has exited or execed: resume threads of the parent the
850 user wanted to be executing. */
853 proceed_after_vfork_done (struct thread_info
*thread
,
856 int pid
= * (int *) arg
;
858 if (ptid_get_pid (thread
->ptid
) == pid
859 && is_running (thread
->ptid
)
860 && !is_executing (thread
->ptid
)
861 && !thread
->stop_requested
862 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
865 fprintf_unfiltered (gdb_stdlog
,
866 "infrun: resuming vfork parent thread %s\n",
867 target_pid_to_str (thread
->ptid
));
869 switch_to_thread (thread
->ptid
);
870 clear_proceed_status (0);
871 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
, 0);
877 /* Called whenever we notice an exec or exit event, to handle
878 detaching or resuming a vfork parent. */
881 handle_vfork_child_exec_or_exit (int exec
)
883 struct inferior
*inf
= current_inferior ();
885 if (inf
->vfork_parent
)
887 int resume_parent
= -1;
889 /* This exec or exit marks the end of the shared memory region
890 between the parent and the child. If the user wanted to
891 detach from the parent, now is the time. */
893 if (inf
->vfork_parent
->pending_detach
)
895 struct thread_info
*tp
;
896 struct cleanup
*old_chain
;
897 struct program_space
*pspace
;
898 struct address_space
*aspace
;
900 /* follow-fork child, detach-on-fork on. */
902 inf
->vfork_parent
->pending_detach
= 0;
906 /* If we're handling a child exit, then inferior_ptid
907 points at the inferior's pid, not to a thread. */
908 old_chain
= save_inferior_ptid ();
909 save_current_program_space ();
910 save_current_inferior ();
913 old_chain
= save_current_space_and_thread ();
915 /* We're letting loose of the parent. */
916 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
917 switch_to_thread (tp
->ptid
);
919 /* We're about to detach from the parent, which implicitly
920 removes breakpoints from its address space. There's a
921 catch here: we want to reuse the spaces for the child,
922 but, parent/child are still sharing the pspace at this
923 point, although the exec in reality makes the kernel give
924 the child a fresh set of new pages. The problem here is
925 that the breakpoints module being unaware of this, would
926 likely chose the child process to write to the parent
927 address space. Swapping the child temporarily away from
928 the spaces has the desired effect. Yes, this is "sort
931 pspace
= inf
->pspace
;
932 aspace
= inf
->aspace
;
936 if (debug_infrun
|| info_verbose
)
938 target_terminal_ours_for_output ();
942 fprintf_filtered (gdb_stdlog
,
943 _("Detaching vfork parent process "
944 "%d after child exec.\n"),
945 inf
->vfork_parent
->pid
);
949 fprintf_filtered (gdb_stdlog
,
950 _("Detaching vfork parent process "
951 "%d after child exit.\n"),
952 inf
->vfork_parent
->pid
);
956 target_detach (NULL
, 0);
959 inf
->pspace
= pspace
;
960 inf
->aspace
= aspace
;
962 do_cleanups (old_chain
);
966 /* We're staying attached to the parent, so, really give the
967 child a new address space. */
968 inf
->pspace
= add_program_space (maybe_new_address_space ());
969 inf
->aspace
= inf
->pspace
->aspace
;
971 set_current_program_space (inf
->pspace
);
973 resume_parent
= inf
->vfork_parent
->pid
;
975 /* Break the bonds. */
976 inf
->vfork_parent
->vfork_child
= NULL
;
980 struct cleanup
*old_chain
;
981 struct program_space
*pspace
;
983 /* If this is a vfork child exiting, then the pspace and
984 aspaces were shared with the parent. Since we're
985 reporting the process exit, we'll be mourning all that is
986 found in the address space, and switching to null_ptid,
987 preparing to start a new inferior. But, since we don't
988 want to clobber the parent's address/program spaces, we
989 go ahead and create a new one for this exiting
992 /* Switch to null_ptid, so that clone_program_space doesn't want
993 to read the selected frame of a dead process. */
994 old_chain
= save_inferior_ptid ();
995 inferior_ptid
= null_ptid
;
997 /* This inferior is dead, so avoid giving the breakpoints
998 module the option to write through to it (cloning a
999 program space resets breakpoints). */
1002 pspace
= add_program_space (maybe_new_address_space ());
1003 set_current_program_space (pspace
);
1005 inf
->symfile_flags
= SYMFILE_NO_READ
;
1006 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1007 inf
->pspace
= pspace
;
1008 inf
->aspace
= pspace
->aspace
;
1010 /* Put back inferior_ptid. We'll continue mourning this
1012 do_cleanups (old_chain
);
1014 resume_parent
= inf
->vfork_parent
->pid
;
1015 /* Break the bonds. */
1016 inf
->vfork_parent
->vfork_child
= NULL
;
1019 inf
->vfork_parent
= NULL
;
1021 gdb_assert (current_program_space
== inf
->pspace
);
1023 if (non_stop
&& resume_parent
!= -1)
1025 /* If the user wanted the parent to be running, let it go
1027 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1030 fprintf_unfiltered (gdb_stdlog
,
1031 "infrun: resuming vfork parent process %d\n",
1034 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1036 do_cleanups (old_chain
);
1041 /* Enum strings for "set|show follow-exec-mode". */
1043 static const char follow_exec_mode_new
[] = "new";
1044 static const char follow_exec_mode_same
[] = "same";
1045 static const char *const follow_exec_mode_names
[] =
1047 follow_exec_mode_new
,
1048 follow_exec_mode_same
,
1052 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1054 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1055 struct cmd_list_element
*c
, const char *value
)
1057 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1060 /* EXECD_PATHNAME is assumed to be non-NULL. */
1063 follow_exec (ptid_t pid
, char *execd_pathname
)
1065 struct thread_info
*th
= inferior_thread ();
1066 struct inferior
*inf
= current_inferior ();
1068 /* This is an exec event that we actually wish to pay attention to.
1069 Refresh our symbol table to the newly exec'd program, remove any
1070 momentary bp's, etc.
1072 If there are breakpoints, they aren't really inserted now,
1073 since the exec() transformed our inferior into a fresh set
1076 We want to preserve symbolic breakpoints on the list, since
1077 we have hopes that they can be reset after the new a.out's
1078 symbol table is read.
1080 However, any "raw" breakpoints must be removed from the list
1081 (e.g., the solib bp's), since their address is probably invalid
1084 And, we DON'T want to call delete_breakpoints() here, since
1085 that may write the bp's "shadow contents" (the instruction
1086 value that was overwritten witha TRAP instruction). Since
1087 we now have a new a.out, those shadow contents aren't valid. */
1089 mark_breakpoints_out ();
1091 update_breakpoints_after_exec ();
1093 /* If there was one, it's gone now. We cannot truly step-to-next
1094 statement through an exec(). */
1095 th
->control
.step_resume_breakpoint
= NULL
;
1096 th
->control
.exception_resume_breakpoint
= NULL
;
1097 th
->control
.single_step_breakpoints
= NULL
;
1098 th
->control
.step_range_start
= 0;
1099 th
->control
.step_range_end
= 0;
1101 /* The target reports the exec event to the main thread, even if
1102 some other thread does the exec, and even if the main thread was
1103 already stopped --- if debugging in non-stop mode, it's possible
1104 the user had the main thread held stopped in the previous image
1105 --- release it now. This is the same behavior as step-over-exec
1106 with scheduler-locking on in all-stop mode. */
1107 th
->stop_requested
= 0;
1109 /* What is this a.out's name? */
1110 printf_unfiltered (_("%s is executing new program: %s\n"),
1111 target_pid_to_str (inferior_ptid
),
1114 /* We've followed the inferior through an exec. Therefore, the
1115 inferior has essentially been killed & reborn. */
1117 gdb_flush (gdb_stdout
);
1119 breakpoint_init_inferior (inf_execd
);
1121 if (gdb_sysroot
&& *gdb_sysroot
)
1123 char *name
= alloca (strlen (gdb_sysroot
)
1124 + strlen (execd_pathname
)
1127 strcpy (name
, gdb_sysroot
);
1128 strcat (name
, execd_pathname
);
1129 execd_pathname
= name
;
1132 /* Reset the shared library package. This ensures that we get a
1133 shlib event when the child reaches "_start", at which point the
1134 dld will have had a chance to initialize the child. */
1135 /* Also, loading a symbol file below may trigger symbol lookups, and
1136 we don't want those to be satisfied by the libraries of the
1137 previous incarnation of this process. */
1138 no_shared_libraries (NULL
, 0);
1140 if (follow_exec_mode_string
== follow_exec_mode_new
)
1142 struct program_space
*pspace
;
1144 /* The user wants to keep the old inferior and program spaces
1145 around. Create a new fresh one, and switch to it. */
1147 inf
= add_inferior (current_inferior ()->pid
);
1148 pspace
= add_program_space (maybe_new_address_space ());
1149 inf
->pspace
= pspace
;
1150 inf
->aspace
= pspace
->aspace
;
1152 exit_inferior_num_silent (current_inferior ()->num
);
1154 set_current_inferior (inf
);
1155 set_current_program_space (pspace
);
1159 /* The old description may no longer be fit for the new image.
1160 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1161 old description; we'll read a new one below. No need to do
1162 this on "follow-exec-mode new", as the old inferior stays
1163 around (its description is later cleared/refetched on
1165 target_clear_description ();
1168 gdb_assert (current_program_space
== inf
->pspace
);
1170 /* That a.out is now the one to use. */
1171 exec_file_attach (execd_pathname
, 0);
1173 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1174 (Position Independent Executable) main symbol file will get applied by
1175 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1176 the breakpoints with the zero displacement. */
1178 symbol_file_add (execd_pathname
,
1180 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1183 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1184 set_initial_language ();
1186 /* If the target can specify a description, read it. Must do this
1187 after flipping to the new executable (because the target supplied
1188 description must be compatible with the executable's
1189 architecture, and the old executable may e.g., be 32-bit, while
1190 the new one 64-bit), and before anything involving memory or
1192 target_find_description ();
1194 solib_create_inferior_hook (0);
1196 jit_inferior_created_hook ();
1198 breakpoint_re_set ();
1200 /* Reinsert all breakpoints. (Those which were symbolic have
1201 been reset to the proper address in the new a.out, thanks
1202 to symbol_file_command...). */
1203 insert_breakpoints ();
1205 /* The next resume of this inferior should bring it to the shlib
1206 startup breakpoints. (If the user had also set bp's on
1207 "main" from the old (parent) process, then they'll auto-
1208 matically get reset there in the new process.). */
1211 /* Info about an instruction that is being stepped over. */
1213 struct step_over_info
1215 /* If we're stepping past a breakpoint, this is the address space
1216 and address of the instruction the breakpoint is set at. We'll
1217 skip inserting all breakpoints here. Valid iff ASPACE is
1219 struct address_space
*aspace
;
1222 /* The instruction being stepped over triggers a nonsteppable
1223 watchpoint. If true, we'll skip inserting watchpoints. */
1224 int nonsteppable_watchpoint_p
;
1227 /* The step-over info of the location that is being stepped over.
1229 Note that with async/breakpoint always-inserted mode, a user might
1230 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1231 being stepped over. As setting a new breakpoint inserts all
1232 breakpoints, we need to make sure the breakpoint being stepped over
1233 isn't inserted then. We do that by only clearing the step-over
1234 info when the step-over is actually finished (or aborted).
1236 Presently GDB can only step over one breakpoint at any given time.
1237 Given threads that can't run code in the same address space as the
1238 breakpoint's can't really miss the breakpoint, GDB could be taught
1239 to step-over at most one breakpoint per address space (so this info
1240 could move to the address space object if/when GDB is extended).
1241 The set of breakpoints being stepped over will normally be much
1242 smaller than the set of all breakpoints, so a flag in the
1243 breakpoint location structure would be wasteful. A separate list
1244 also saves complexity and run-time, as otherwise we'd have to go
1245 through all breakpoint locations clearing their flag whenever we
1246 start a new sequence. Similar considerations weigh against storing
1247 this info in the thread object. Plus, not all step overs actually
1248 have breakpoint locations -- e.g., stepping past a single-step
1249 breakpoint, or stepping to complete a non-continuable
1251 static struct step_over_info step_over_info
;
1253 /* Record the address of the breakpoint/instruction we're currently
1257 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1258 int nonsteppable_watchpoint_p
)
1260 step_over_info
.aspace
= aspace
;
1261 step_over_info
.address
= address
;
1262 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1265 /* Called when we're not longer stepping over a breakpoint / an
1266 instruction, so all breakpoints are free to be (re)inserted. */
1269 clear_step_over_info (void)
1271 step_over_info
.aspace
= NULL
;
1272 step_over_info
.address
= 0;
1273 step_over_info
.nonsteppable_watchpoint_p
= 0;
1279 stepping_past_instruction_at (struct address_space
*aspace
,
1282 return (step_over_info
.aspace
!= NULL
1283 && breakpoint_address_match (aspace
, address
,
1284 step_over_info
.aspace
,
1285 step_over_info
.address
));
1291 stepping_past_nonsteppable_watchpoint (void)
1293 return step_over_info
.nonsteppable_watchpoint_p
;
1296 /* Returns true if step-over info is valid. */
1299 step_over_info_valid_p (void)
1301 return (step_over_info
.aspace
!= NULL
1302 || stepping_past_nonsteppable_watchpoint ());
1306 /* Displaced stepping. */
1308 /* In non-stop debugging mode, we must take special care to manage
1309 breakpoints properly; in particular, the traditional strategy for
1310 stepping a thread past a breakpoint it has hit is unsuitable.
1311 'Displaced stepping' is a tactic for stepping one thread past a
1312 breakpoint it has hit while ensuring that other threads running
1313 concurrently will hit the breakpoint as they should.
1315 The traditional way to step a thread T off a breakpoint in a
1316 multi-threaded program in all-stop mode is as follows:
1318 a0) Initially, all threads are stopped, and breakpoints are not
1320 a1) We single-step T, leaving breakpoints uninserted.
1321 a2) We insert breakpoints, and resume all threads.
1323 In non-stop debugging, however, this strategy is unsuitable: we
1324 don't want to have to stop all threads in the system in order to
1325 continue or step T past a breakpoint. Instead, we use displaced
1328 n0) Initially, T is stopped, other threads are running, and
1329 breakpoints are inserted.
1330 n1) We copy the instruction "under" the breakpoint to a separate
1331 location, outside the main code stream, making any adjustments
1332 to the instruction, register, and memory state as directed by
1334 n2) We single-step T over the instruction at its new location.
1335 n3) We adjust the resulting register and memory state as directed
1336 by T's architecture. This includes resetting T's PC to point
1337 back into the main instruction stream.
1340 This approach depends on the following gdbarch methods:
1342 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1343 indicate where to copy the instruction, and how much space must
1344 be reserved there. We use these in step n1.
1346 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1347 address, and makes any necessary adjustments to the instruction,
1348 register contents, and memory. We use this in step n1.
1350 - gdbarch_displaced_step_fixup adjusts registers and memory after
1351 we have successfuly single-stepped the instruction, to yield the
1352 same effect the instruction would have had if we had executed it
1353 at its original address. We use this in step n3.
1355 - gdbarch_displaced_step_free_closure provides cleanup.
1357 The gdbarch_displaced_step_copy_insn and
1358 gdbarch_displaced_step_fixup functions must be written so that
1359 copying an instruction with gdbarch_displaced_step_copy_insn,
1360 single-stepping across the copied instruction, and then applying
1361 gdbarch_displaced_insn_fixup should have the same effects on the
1362 thread's memory and registers as stepping the instruction in place
1363 would have. Exactly which responsibilities fall to the copy and
1364 which fall to the fixup is up to the author of those functions.
1366 See the comments in gdbarch.sh for details.
1368 Note that displaced stepping and software single-step cannot
1369 currently be used in combination, although with some care I think
1370 they could be made to. Software single-step works by placing
1371 breakpoints on all possible subsequent instructions; if the
1372 displaced instruction is a PC-relative jump, those breakpoints
1373 could fall in very strange places --- on pages that aren't
1374 executable, or at addresses that are not proper instruction
1375 boundaries. (We do generally let other threads run while we wait
1376 to hit the software single-step breakpoint, and they might
1377 encounter such a corrupted instruction.) One way to work around
1378 this would be to have gdbarch_displaced_step_copy_insn fully
1379 simulate the effect of PC-relative instructions (and return NULL)
1380 on architectures that use software single-stepping.
1382 In non-stop mode, we can have independent and simultaneous step
1383 requests, so more than one thread may need to simultaneously step
1384 over a breakpoint. The current implementation assumes there is
1385 only one scratch space per process. In this case, we have to
1386 serialize access to the scratch space. If thread A wants to step
1387 over a breakpoint, but we are currently waiting for some other
1388 thread to complete a displaced step, we leave thread A stopped and
1389 place it in the displaced_step_request_queue. Whenever a displaced
1390 step finishes, we pick the next thread in the queue and start a new
1391 displaced step operation on it. See displaced_step_prepare and
1392 displaced_step_fixup for details. */
1394 struct displaced_step_request
1397 struct displaced_step_request
*next
;
1400 /* Per-inferior displaced stepping state. */
1401 struct displaced_step_inferior_state
1403 /* Pointer to next in linked list. */
1404 struct displaced_step_inferior_state
*next
;
1406 /* The process this displaced step state refers to. */
1409 /* A queue of pending displaced stepping requests. One entry per
1410 thread that needs to do a displaced step. */
1411 struct displaced_step_request
*step_request_queue
;
1413 /* If this is not null_ptid, this is the thread carrying out a
1414 displaced single-step in process PID. This thread's state will
1415 require fixing up once it has completed its step. */
1418 /* The architecture the thread had when we stepped it. */
1419 struct gdbarch
*step_gdbarch
;
1421 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1422 for post-step cleanup. */
1423 struct displaced_step_closure
*step_closure
;
1425 /* The address of the original instruction, and the copy we
1427 CORE_ADDR step_original
, step_copy
;
1429 /* Saved contents of copy area. */
1430 gdb_byte
*step_saved_copy
;
1433 /* The list of states of processes involved in displaced stepping
1435 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1437 /* Get the displaced stepping state of process PID. */
1439 static struct displaced_step_inferior_state
*
1440 get_displaced_stepping_state (int pid
)
1442 struct displaced_step_inferior_state
*state
;
1444 for (state
= displaced_step_inferior_states
;
1446 state
= state
->next
)
1447 if (state
->pid
== pid
)
1453 /* Add a new displaced stepping state for process PID to the displaced
1454 stepping state list, or return a pointer to an already existing
1455 entry, if it already exists. Never returns NULL. */
1457 static struct displaced_step_inferior_state
*
1458 add_displaced_stepping_state (int pid
)
1460 struct displaced_step_inferior_state
*state
;
1462 for (state
= displaced_step_inferior_states
;
1464 state
= state
->next
)
1465 if (state
->pid
== pid
)
1468 state
= xcalloc (1, sizeof (*state
));
1470 state
->next
= displaced_step_inferior_states
;
1471 displaced_step_inferior_states
= state
;
1476 /* If inferior is in displaced stepping, and ADDR equals to starting address
1477 of copy area, return corresponding displaced_step_closure. Otherwise,
1480 struct displaced_step_closure
*
1481 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1483 struct displaced_step_inferior_state
*displaced
1484 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1486 /* If checking the mode of displaced instruction in copy area. */
1487 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1488 && (displaced
->step_copy
== addr
))
1489 return displaced
->step_closure
;
1494 /* Remove the displaced stepping state of process PID. */
1497 remove_displaced_stepping_state (int pid
)
1499 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1501 gdb_assert (pid
!= 0);
1503 it
= displaced_step_inferior_states
;
1504 prev_next_p
= &displaced_step_inferior_states
;
1509 *prev_next_p
= it
->next
;
1514 prev_next_p
= &it
->next
;
1520 infrun_inferior_exit (struct inferior
*inf
)
1522 remove_displaced_stepping_state (inf
->pid
);
1525 /* If ON, and the architecture supports it, GDB will use displaced
1526 stepping to step over breakpoints. If OFF, or if the architecture
1527 doesn't support it, GDB will instead use the traditional
1528 hold-and-step approach. If AUTO (which is the default), GDB will
1529 decide which technique to use to step over breakpoints depending on
1530 which of all-stop or non-stop mode is active --- displaced stepping
1531 in non-stop mode; hold-and-step in all-stop mode. */
1533 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1536 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1537 struct cmd_list_element
*c
,
1540 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1541 fprintf_filtered (file
,
1542 _("Debugger's willingness to use displaced stepping "
1543 "to step over breakpoints is %s (currently %s).\n"),
1544 value
, non_stop
? "on" : "off");
1546 fprintf_filtered (file
,
1547 _("Debugger's willingness to use displaced stepping "
1548 "to step over breakpoints is %s.\n"), value
);
1551 /* Return non-zero if displaced stepping can/should be used to step
1552 over breakpoints. */
1555 use_displaced_stepping (struct gdbarch
*gdbarch
)
1557 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
&& non_stop
)
1558 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1559 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1560 && find_record_target () == NULL
);
1563 /* Clean out any stray displaced stepping state. */
1565 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1567 /* Indicate that there is no cleanup pending. */
1568 displaced
->step_ptid
= null_ptid
;
1570 if (displaced
->step_closure
)
1572 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1573 displaced
->step_closure
);
1574 displaced
->step_closure
= NULL
;
1579 displaced_step_clear_cleanup (void *arg
)
1581 struct displaced_step_inferior_state
*state
= arg
;
1583 displaced_step_clear (state
);
1586 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1588 displaced_step_dump_bytes (struct ui_file
*file
,
1589 const gdb_byte
*buf
,
1594 for (i
= 0; i
< len
; i
++)
1595 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1596 fputs_unfiltered ("\n", file
);
1599 /* Prepare to single-step, using displaced stepping.
1601 Note that we cannot use displaced stepping when we have a signal to
1602 deliver. If we have a signal to deliver and an instruction to step
1603 over, then after the step, there will be no indication from the
1604 target whether the thread entered a signal handler or ignored the
1605 signal and stepped over the instruction successfully --- both cases
1606 result in a simple SIGTRAP. In the first case we mustn't do a
1607 fixup, and in the second case we must --- but we can't tell which.
1608 Comments in the code for 'random signals' in handle_inferior_event
1609 explain how we handle this case instead.
1611 Returns 1 if preparing was successful -- this thread is going to be
1612 stepped now; or 0 if displaced stepping this thread got queued. */
1614 displaced_step_prepare (ptid_t ptid
)
1616 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1617 struct thread_info
*tp
= find_thread_ptid (ptid
);
1618 struct regcache
*regcache
= get_thread_regcache (ptid
);
1619 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1620 CORE_ADDR original
, copy
;
1622 struct displaced_step_closure
*closure
;
1623 struct displaced_step_inferior_state
*displaced
;
1626 /* We should never reach this function if the architecture does not
1627 support displaced stepping. */
1628 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1630 /* Disable range stepping while executing in the scratch pad. We
1631 want a single-step even if executing the displaced instruction in
1632 the scratch buffer lands within the stepping range (e.g., a
1634 tp
->control
.may_range_step
= 0;
1636 /* We have to displaced step one thread at a time, as we only have
1637 access to a single scratch space per inferior. */
1639 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1641 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1643 /* Already waiting for a displaced step to finish. Defer this
1644 request and place in queue. */
1645 struct displaced_step_request
*req
, *new_req
;
1647 if (debug_displaced
)
1648 fprintf_unfiltered (gdb_stdlog
,
1649 "displaced: defering step of %s\n",
1650 target_pid_to_str (ptid
));
1652 new_req
= xmalloc (sizeof (*new_req
));
1653 new_req
->ptid
= ptid
;
1654 new_req
->next
= NULL
;
1656 if (displaced
->step_request_queue
)
1658 for (req
= displaced
->step_request_queue
;
1662 req
->next
= new_req
;
1665 displaced
->step_request_queue
= new_req
;
1671 if (debug_displaced
)
1672 fprintf_unfiltered (gdb_stdlog
,
1673 "displaced: stepping %s now\n",
1674 target_pid_to_str (ptid
));
1677 displaced_step_clear (displaced
);
1679 old_cleanups
= save_inferior_ptid ();
1680 inferior_ptid
= ptid
;
1682 original
= regcache_read_pc (regcache
);
1684 copy
= gdbarch_displaced_step_location (gdbarch
);
1685 len
= gdbarch_max_insn_length (gdbarch
);
1687 /* Save the original contents of the copy area. */
1688 displaced
->step_saved_copy
= xmalloc (len
);
1689 ignore_cleanups
= make_cleanup (free_current_contents
,
1690 &displaced
->step_saved_copy
);
1691 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1693 throw_error (MEMORY_ERROR
,
1694 _("Error accessing memory address %s (%s) for "
1695 "displaced-stepping scratch space."),
1696 paddress (gdbarch
, copy
), safe_strerror (status
));
1697 if (debug_displaced
)
1699 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1700 paddress (gdbarch
, copy
));
1701 displaced_step_dump_bytes (gdb_stdlog
,
1702 displaced
->step_saved_copy
,
1706 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1707 original
, copy
, regcache
);
1709 /* We don't support the fully-simulated case at present. */
1710 gdb_assert (closure
);
1712 /* Save the information we need to fix things up if the step
1714 displaced
->step_ptid
= ptid
;
1715 displaced
->step_gdbarch
= gdbarch
;
1716 displaced
->step_closure
= closure
;
1717 displaced
->step_original
= original
;
1718 displaced
->step_copy
= copy
;
1720 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1722 /* Resume execution at the copy. */
1723 regcache_write_pc (regcache
, copy
);
1725 discard_cleanups (ignore_cleanups
);
1727 do_cleanups (old_cleanups
);
1729 if (debug_displaced
)
1730 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1731 paddress (gdbarch
, copy
));
1737 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1738 const gdb_byte
*myaddr
, int len
)
1740 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1742 inferior_ptid
= ptid
;
1743 write_memory (memaddr
, myaddr
, len
);
1744 do_cleanups (ptid_cleanup
);
1747 /* Restore the contents of the copy area for thread PTID. */
1750 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1753 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1755 write_memory_ptid (ptid
, displaced
->step_copy
,
1756 displaced
->step_saved_copy
, len
);
1757 if (debug_displaced
)
1758 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1759 target_pid_to_str (ptid
),
1760 paddress (displaced
->step_gdbarch
,
1761 displaced
->step_copy
));
1765 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1767 struct cleanup
*old_cleanups
;
1768 struct displaced_step_inferior_state
*displaced
1769 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1771 /* Was any thread of this process doing a displaced step? */
1772 if (displaced
== NULL
)
1775 /* Was this event for the pid we displaced? */
1776 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1777 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1780 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1782 displaced_step_restore (displaced
, displaced
->step_ptid
);
1784 /* Did the instruction complete successfully? */
1785 if (signal
== GDB_SIGNAL_TRAP
)
1787 /* Fix up the resulting state. */
1788 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1789 displaced
->step_closure
,
1790 displaced
->step_original
,
1791 displaced
->step_copy
,
1792 get_thread_regcache (displaced
->step_ptid
));
1796 /* Since the instruction didn't complete, all we can do is
1798 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1799 CORE_ADDR pc
= regcache_read_pc (regcache
);
1801 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1802 regcache_write_pc (regcache
, pc
);
1805 do_cleanups (old_cleanups
);
1807 displaced
->step_ptid
= null_ptid
;
1809 /* Are there any pending displaced stepping requests? If so, run
1810 one now. Leave the state object around, since we're likely to
1811 need it again soon. */
1812 while (displaced
->step_request_queue
)
1814 struct displaced_step_request
*head
;
1816 struct regcache
*regcache
;
1817 struct gdbarch
*gdbarch
;
1818 CORE_ADDR actual_pc
;
1819 struct address_space
*aspace
;
1821 head
= displaced
->step_request_queue
;
1823 displaced
->step_request_queue
= head
->next
;
1826 context_switch (ptid
);
1828 regcache
= get_thread_regcache (ptid
);
1829 actual_pc
= regcache_read_pc (regcache
);
1830 aspace
= get_regcache_aspace (regcache
);
1832 if (breakpoint_here_p (aspace
, actual_pc
))
1834 if (debug_displaced
)
1835 fprintf_unfiltered (gdb_stdlog
,
1836 "displaced: stepping queued %s now\n",
1837 target_pid_to_str (ptid
));
1839 displaced_step_prepare (ptid
);
1841 gdbarch
= get_regcache_arch (regcache
);
1843 if (debug_displaced
)
1845 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1848 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1849 paddress (gdbarch
, actual_pc
));
1850 read_memory (actual_pc
, buf
, sizeof (buf
));
1851 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1854 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1855 displaced
->step_closure
))
1856 target_resume (ptid
, 1, GDB_SIGNAL_0
);
1858 target_resume (ptid
, 0, GDB_SIGNAL_0
);
1860 /* Done, we're stepping a thread. */
1866 struct thread_info
*tp
= inferior_thread ();
1868 /* The breakpoint we were sitting under has since been
1870 tp
->control
.trap_expected
= 0;
1872 /* Go back to what we were trying to do. */
1873 step
= currently_stepping (tp
);
1875 if (debug_displaced
)
1876 fprintf_unfiltered (gdb_stdlog
,
1877 "displaced: breakpoint is gone: %s, step(%d)\n",
1878 target_pid_to_str (tp
->ptid
), step
);
1880 target_resume (ptid
, step
, GDB_SIGNAL_0
);
1881 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1883 /* This request was discarded. See if there's any other
1884 thread waiting for its turn. */
1889 /* Update global variables holding ptids to hold NEW_PTID if they were
1890 holding OLD_PTID. */
1892 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1894 struct displaced_step_request
*it
;
1895 struct displaced_step_inferior_state
*displaced
;
1897 if (ptid_equal (inferior_ptid
, old_ptid
))
1898 inferior_ptid
= new_ptid
;
1900 for (displaced
= displaced_step_inferior_states
;
1902 displaced
= displaced
->next
)
1904 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1905 displaced
->step_ptid
= new_ptid
;
1907 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1908 if (ptid_equal (it
->ptid
, old_ptid
))
1909 it
->ptid
= new_ptid
;
1916 /* Things to clean up if we QUIT out of resume (). */
1918 resume_cleanups (void *ignore
)
1920 if (!ptid_equal (inferior_ptid
, null_ptid
))
1921 delete_single_step_breakpoints (inferior_thread ());
1926 static const char schedlock_off
[] = "off";
1927 static const char schedlock_on
[] = "on";
1928 static const char schedlock_step
[] = "step";
1929 static const char *const scheduler_enums
[] = {
1935 static const char *scheduler_mode
= schedlock_off
;
1937 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1938 struct cmd_list_element
*c
, const char *value
)
1940 fprintf_filtered (file
,
1941 _("Mode for locking scheduler "
1942 "during execution is \"%s\".\n"),
1947 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1949 if (!target_can_lock_scheduler
)
1951 scheduler_mode
= schedlock_off
;
1952 error (_("Target '%s' cannot support this command."), target_shortname
);
1956 /* True if execution commands resume all threads of all processes by
1957 default; otherwise, resume only threads of the current inferior
1959 int sched_multi
= 0;
1961 /* Try to setup for software single stepping over the specified location.
1962 Return 1 if target_resume() should use hardware single step.
1964 GDBARCH the current gdbarch.
1965 PC the location to step over. */
1968 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1972 if (execution_direction
== EXEC_FORWARD
1973 && gdbarch_software_single_step_p (gdbarch
)
1974 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1982 user_visible_resume_ptid (int step
)
1984 /* By default, resume all threads of all processes. */
1985 ptid_t resume_ptid
= RESUME_ALL
;
1987 /* Maybe resume only all threads of the current process. */
1988 if (!sched_multi
&& target_supports_multi_process ())
1990 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1993 /* Maybe resume a single thread after all. */
1996 /* With non-stop mode on, threads are always handled
1998 resume_ptid
= inferior_ptid
;
2000 else if ((scheduler_mode
== schedlock_on
)
2001 || (scheduler_mode
== schedlock_step
&& step
))
2003 /* User-settable 'scheduler' mode requires solo thread resume. */
2004 resume_ptid
= inferior_ptid
;
2007 /* We may actually resume fewer threads at first, e.g., if a thread
2008 is stopped at a breakpoint that needs stepping-off, but that
2009 should not be visible to the user/frontend, and neither should
2010 the frontend/user be allowed to proceed any of the threads that
2011 happen to be stopped for internal run control handling, if a
2012 previous command wanted them resumed. */
2016 /* Resume the inferior, but allow a QUIT. This is useful if the user
2017 wants to interrupt some lengthy single-stepping operation
2018 (for child processes, the SIGINT goes to the inferior, and so
2019 we get a SIGINT random_signal, but for remote debugging and perhaps
2020 other targets, that's not true).
2022 STEP nonzero if we should step (zero to continue instead).
2023 SIG is the signal to give the inferior (zero for none). */
2025 resume (int step
, enum gdb_signal sig
)
2027 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2028 struct regcache
*regcache
= get_current_regcache ();
2029 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2030 struct thread_info
*tp
= inferior_thread ();
2031 CORE_ADDR pc
= regcache_read_pc (regcache
);
2032 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2034 /* From here on, this represents the caller's step vs continue
2035 request, while STEP represents what we'll actually request the
2036 target to do. STEP can decay from a step to a continue, if e.g.,
2037 we need to implement single-stepping with breakpoints (software
2038 single-step). When deciding whether "set scheduler-locking step"
2039 applies, it's the callers intention that counts. */
2040 const int entry_step
= step
;
2042 tp
->stepped_breakpoint
= 0;
2046 if (current_inferior ()->waiting_for_vfork_done
)
2048 /* Don't try to single-step a vfork parent that is waiting for
2049 the child to get out of the shared memory region (by exec'ing
2050 or exiting). This is particularly important on software
2051 single-step archs, as the child process would trip on the
2052 software single step breakpoint inserted for the parent
2053 process. Since the parent will not actually execute any
2054 instruction until the child is out of the shared region (such
2055 are vfork's semantics), it is safe to simply continue it.
2056 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2057 the parent, and tell it to `keep_going', which automatically
2058 re-sets it stepping. */
2060 fprintf_unfiltered (gdb_stdlog
,
2061 "infrun: resume : clear step\n");
2066 fprintf_unfiltered (gdb_stdlog
,
2067 "infrun: resume (step=%d, signal=%s), "
2068 "trap_expected=%d, current thread [%s] at %s\n",
2069 step
, gdb_signal_to_symbol_string (sig
),
2070 tp
->control
.trap_expected
,
2071 target_pid_to_str (inferior_ptid
),
2072 paddress (gdbarch
, pc
));
2074 /* Normally, by the time we reach `resume', the breakpoints are either
2075 removed or inserted, as appropriate. The exception is if we're sitting
2076 at a permanent breakpoint; we need to step over it, but permanent
2077 breakpoints can't be removed. So we have to test for it here. */
2078 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2080 if (sig
!= GDB_SIGNAL_0
)
2082 /* We have a signal to pass to the inferior. The resume
2083 may, or may not take us to the signal handler. If this
2084 is a step, we'll need to stop in the signal handler, if
2085 there's one, (if the target supports stepping into
2086 handlers), or in the next mainline instruction, if
2087 there's no handler. If this is a continue, we need to be
2088 sure to run the handler with all breakpoints inserted.
2089 In all cases, set a breakpoint at the current address
2090 (where the handler returns to), and once that breakpoint
2091 is hit, resume skipping the permanent breakpoint. If
2092 that breakpoint isn't hit, then we've stepped into the
2093 signal handler (or hit some other event). We'll delete
2094 the step-resume breakpoint then. */
2097 fprintf_unfiltered (gdb_stdlog
,
2098 "infrun: resume: skipping permanent breakpoint, "
2099 "deliver signal first\n");
2101 clear_step_over_info ();
2102 tp
->control
.trap_expected
= 0;
2104 if (tp
->control
.step_resume_breakpoint
== NULL
)
2106 /* Set a "high-priority" step-resume, as we don't want
2107 user breakpoints at PC to trigger (again) when this
2109 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2110 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2112 tp
->step_after_step_resume_breakpoint
= step
;
2115 insert_breakpoints ();
2119 /* There's no signal to pass, we can go ahead and skip the
2120 permanent breakpoint manually. */
2122 fprintf_unfiltered (gdb_stdlog
,
2123 "infrun: resume: skipping permanent breakpoint\n");
2124 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2125 /* Update pc to reflect the new address from which we will
2126 execute instructions. */
2127 pc
= regcache_read_pc (regcache
);
2131 /* We've already advanced the PC, so the stepping part
2132 is done. Now we need to arrange for a trap to be
2133 reported to handle_inferior_event. Set a breakpoint
2134 at the current PC, and run to it. Don't update
2135 prev_pc, because if we end in
2136 switch_back_to_stepping, we want the "expected thread
2137 advanced also" branch to be taken. IOW, we don't
2138 want this thread to step further from PC
2140 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2141 insert_breakpoints ();
2143 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2144 /* We're continuing with all breakpoints inserted. It's
2145 safe to let the target bypass signals. */
2146 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2147 /* ... and safe to let other threads run, according to
2149 resume_ptid
= user_visible_resume_ptid (entry_step
);
2150 target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2151 discard_cleanups (old_cleanups
);
2157 /* If we have a breakpoint to step over, make sure to do a single
2158 step only. Same if we have software watchpoints. */
2159 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2160 tp
->control
.may_range_step
= 0;
2162 /* If enabled, step over breakpoints by executing a copy of the
2163 instruction at a different address.
2165 We can't use displaced stepping when we have a signal to deliver;
2166 the comments for displaced_step_prepare explain why. The
2167 comments in the handle_inferior event for dealing with 'random
2168 signals' explain what we do instead.
2170 We can't use displaced stepping when we are waiting for vfork_done
2171 event, displaced stepping breaks the vfork child similarly as single
2172 step software breakpoint. */
2173 if (use_displaced_stepping (gdbarch
)
2174 && tp
->control
.trap_expected
2175 && sig
== GDB_SIGNAL_0
2176 && !current_inferior ()->waiting_for_vfork_done
)
2178 struct displaced_step_inferior_state
*displaced
;
2180 if (!displaced_step_prepare (inferior_ptid
))
2182 /* Got placed in displaced stepping queue. Will be resumed
2183 later when all the currently queued displaced stepping
2184 requests finish. The thread is not executing at this
2185 point, and the call to set_executing will be made later.
2186 But we need to call set_running here, since from the
2187 user/frontend's point of view, threads were set running.
2188 Unless we're calling an inferior function, as in that
2189 case we pretend the inferior doesn't run at all. */
2190 if (!tp
->control
.in_infcall
)
2191 set_running (user_visible_resume_ptid (entry_step
), 1);
2192 discard_cleanups (old_cleanups
);
2196 /* Update pc to reflect the new address from which we will execute
2197 instructions due to displaced stepping. */
2198 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2200 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2201 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2202 displaced
->step_closure
);
2205 /* Do we need to do it the hard way, w/temp breakpoints? */
2207 step
= maybe_software_singlestep (gdbarch
, pc
);
2209 /* Currently, our software single-step implementation leads to different
2210 results than hardware single-stepping in one situation: when stepping
2211 into delivering a signal which has an associated signal handler,
2212 hardware single-step will stop at the first instruction of the handler,
2213 while software single-step will simply skip execution of the handler.
2215 For now, this difference in behavior is accepted since there is no
2216 easy way to actually implement single-stepping into a signal handler
2217 without kernel support.
2219 However, there is one scenario where this difference leads to follow-on
2220 problems: if we're stepping off a breakpoint by removing all breakpoints
2221 and then single-stepping. In this case, the software single-step
2222 behavior means that even if there is a *breakpoint* in the signal
2223 handler, GDB still would not stop.
2225 Fortunately, we can at least fix this particular issue. We detect
2226 here the case where we are about to deliver a signal while software
2227 single-stepping with breakpoints removed. In this situation, we
2228 revert the decisions to remove all breakpoints and insert single-
2229 step breakpoints, and instead we install a step-resume breakpoint
2230 at the current address, deliver the signal without stepping, and
2231 once we arrive back at the step-resume breakpoint, actually step
2232 over the breakpoint we originally wanted to step over. */
2233 if (thread_has_single_step_breakpoints_set (tp
)
2234 && sig
!= GDB_SIGNAL_0
2235 && step_over_info_valid_p ())
2237 /* If we have nested signals or a pending signal is delivered
2238 immediately after a handler returns, might might already have
2239 a step-resume breakpoint set on the earlier handler. We cannot
2240 set another step-resume breakpoint; just continue on until the
2241 original breakpoint is hit. */
2242 if (tp
->control
.step_resume_breakpoint
== NULL
)
2244 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2245 tp
->step_after_step_resume_breakpoint
= 1;
2248 delete_single_step_breakpoints (tp
);
2250 clear_step_over_info ();
2251 tp
->control
.trap_expected
= 0;
2253 insert_breakpoints ();
2256 /* If STEP is set, it's a request to use hardware stepping
2257 facilities. But in that case, we should never
2258 use singlestep breakpoint. */
2259 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2261 /* Decide the set of threads to ask the target to resume. Start
2262 by assuming everything will be resumed, than narrow the set
2263 by applying increasingly restricting conditions. */
2264 resume_ptid
= user_visible_resume_ptid (entry_step
);
2266 /* Even if RESUME_PTID is a wildcard, and we end up resuming less
2267 (e.g., we might need to step over a breakpoint), from the
2268 user/frontend's point of view, all threads in RESUME_PTID are now
2269 running. Unless we're calling an inferior function, as in that
2270 case pretend we inferior doesn't run at all. */
2271 if (!tp
->control
.in_infcall
)
2272 set_running (resume_ptid
, 1);
2274 /* Maybe resume a single thread after all. */
2275 if ((step
|| thread_has_single_step_breakpoints_set (tp
))
2276 && tp
->control
.trap_expected
)
2278 /* We're allowing a thread to run past a breakpoint it has
2279 hit, by single-stepping the thread with the breakpoint
2280 removed. In which case, we need to single-step only this
2281 thread, and keep others stopped, as they can miss this
2282 breakpoint if allowed to run. */
2283 resume_ptid
= inferior_ptid
;
2286 if (execution_direction
!= EXEC_REVERSE
2287 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2289 /* The only case we currently need to step a breakpoint
2290 instruction is when we have a signal to deliver. See
2291 handle_signal_stop where we handle random signals that could
2292 take out us out of the stepping range. Normally, in that
2293 case we end up continuing (instead of stepping) over the
2294 signal handler with a breakpoint at PC, but there are cases
2295 where we should _always_ single-step, even if we have a
2296 step-resume breakpoint, like when a software watchpoint is
2297 set. Assuming single-stepping and delivering a signal at the
2298 same time would takes us to the signal handler, then we could
2299 have removed the breakpoint at PC to step over it. However,
2300 some hardware step targets (like e.g., Mac OS) can't step
2301 into signal handlers, and for those, we need to leave the
2302 breakpoint at PC inserted, as otherwise if the handler
2303 recurses and executes PC again, it'll miss the breakpoint.
2304 So we leave the breakpoint inserted anyway, but we need to
2305 record that we tried to step a breakpoint instruction, so
2306 that adjust_pc_after_break doesn't end up confused. */
2307 gdb_assert (sig
!= GDB_SIGNAL_0
);
2309 tp
->stepped_breakpoint
= 1;
2311 /* Most targets can step a breakpoint instruction, thus
2312 executing it normally. But if this one cannot, just
2313 continue and we will hit it anyway. */
2314 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2319 && use_displaced_stepping (gdbarch
)
2320 && tp
->control
.trap_expected
)
2322 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
2323 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2324 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2327 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2328 paddress (resume_gdbarch
, actual_pc
));
2329 read_memory (actual_pc
, buf
, sizeof (buf
));
2330 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2333 if (tp
->control
.may_range_step
)
2335 /* If we're resuming a thread with the PC out of the step
2336 range, then we're doing some nested/finer run control
2337 operation, like stepping the thread out of the dynamic
2338 linker or the displaced stepping scratch pad. We
2339 shouldn't have allowed a range step then. */
2340 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2343 /* Install inferior's terminal modes. */
2344 target_terminal_inferior ();
2346 /* Avoid confusing the next resume, if the next stop/resume
2347 happens to apply to another thread. */
2348 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2350 /* Advise target which signals may be handled silently. If we have
2351 removed breakpoints because we are stepping over one (in any
2352 thread), we need to receive all signals to avoid accidentally
2353 skipping a breakpoint during execution of a signal handler. */
2354 if (step_over_info_valid_p ())
2355 target_pass_signals (0, NULL
);
2357 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2359 target_resume (resume_ptid
, step
, sig
);
2361 discard_cleanups (old_cleanups
);
2366 /* Clear out all variables saying what to do when inferior is continued.
2367 First do this, then set the ones you want, then call `proceed'. */
2370 clear_proceed_status_thread (struct thread_info
*tp
)
2373 fprintf_unfiltered (gdb_stdlog
,
2374 "infrun: clear_proceed_status_thread (%s)\n",
2375 target_pid_to_str (tp
->ptid
));
2377 /* If this signal should not be seen by program, give it zero.
2378 Used for debugging signals. */
2379 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2380 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2382 tp
->control
.trap_expected
= 0;
2383 tp
->control
.step_range_start
= 0;
2384 tp
->control
.step_range_end
= 0;
2385 tp
->control
.may_range_step
= 0;
2386 tp
->control
.step_frame_id
= null_frame_id
;
2387 tp
->control
.step_stack_frame_id
= null_frame_id
;
2388 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2389 tp
->stop_requested
= 0;
2391 tp
->control
.stop_step
= 0;
2393 tp
->control
.proceed_to_finish
= 0;
2395 tp
->control
.command_interp
= NULL
;
2397 /* Discard any remaining commands or status from previous stop. */
2398 bpstat_clear (&tp
->control
.stop_bpstat
);
2402 clear_proceed_status (int step
)
2406 struct thread_info
*tp
;
2409 resume_ptid
= user_visible_resume_ptid (step
);
2411 /* In all-stop mode, delete the per-thread status of all threads
2412 we're about to resume, implicitly and explicitly. */
2413 ALL_NON_EXITED_THREADS (tp
)
2415 if (!ptid_match (tp
->ptid
, resume_ptid
))
2417 clear_proceed_status_thread (tp
);
2421 if (!ptid_equal (inferior_ptid
, null_ptid
))
2423 struct inferior
*inferior
;
2427 /* If in non-stop mode, only delete the per-thread status of
2428 the current thread. */
2429 clear_proceed_status_thread (inferior_thread ());
2432 inferior
= current_inferior ();
2433 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2436 stop_after_trap
= 0;
2438 clear_step_over_info ();
2440 observer_notify_about_to_proceed ();
2444 regcache_xfree (stop_registers
);
2445 stop_registers
= NULL
;
2449 /* Returns true if TP is still stopped at a breakpoint that needs
2450 stepping-over in order to make progress. If the breakpoint is gone
2451 meanwhile, we can skip the whole step-over dance. */
2454 thread_still_needs_step_over (struct thread_info
*tp
)
2456 if (tp
->stepping_over_breakpoint
)
2458 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2460 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2461 regcache_read_pc (regcache
))
2462 == ordinary_breakpoint_here
)
2465 tp
->stepping_over_breakpoint
= 0;
2471 /* Returns true if scheduler locking applies. STEP indicates whether
2472 we're about to do a step/next-like command to a thread. */
2475 schedlock_applies (int step
)
2477 return (scheduler_mode
== schedlock_on
2478 || (scheduler_mode
== schedlock_step
2482 /* Look a thread other than EXCEPT that has previously reported a
2483 breakpoint event, and thus needs a step-over in order to make
2484 progress. Returns NULL is none is found. STEP indicates whether
2485 we're about to step the current thread, in order to decide whether
2486 "set scheduler-locking step" applies. */
2488 static struct thread_info
*
2489 find_thread_needs_step_over (int step
, struct thread_info
*except
)
2491 struct thread_info
*tp
, *current
;
2493 /* With non-stop mode on, threads are always handled individually. */
2494 gdb_assert (! non_stop
);
2496 current
= inferior_thread ();
2498 /* If scheduler locking applies, we can avoid iterating over all
2500 if (schedlock_applies (step
))
2502 if (except
!= current
2503 && thread_still_needs_step_over (current
))
2509 ALL_NON_EXITED_THREADS (tp
)
2511 /* Ignore the EXCEPT thread. */
2514 /* Ignore threads of processes we're not resuming. */
2516 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
2519 if (thread_still_needs_step_over (tp
))
2526 /* Basic routine for continuing the program in various fashions.
2528 ADDR is the address to resume at, or -1 for resume where stopped.
2529 SIGGNAL is the signal to give it, or 0 for none,
2530 or -1 for act according to how it stopped.
2531 STEP is nonzero if should trap after one instruction.
2532 -1 means return after that and print nothing.
2533 You should probably set various step_... variables
2534 before calling here, if you are stepping.
2536 You should call clear_proceed_status before calling proceed. */
2539 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
, int step
)
2541 struct regcache
*regcache
;
2542 struct gdbarch
*gdbarch
;
2543 struct thread_info
*tp
;
2545 struct address_space
*aspace
;
2547 /* If we're stopped at a fork/vfork, follow the branch set by the
2548 "set follow-fork-mode" command; otherwise, we'll just proceed
2549 resuming the current thread. */
2550 if (!follow_fork ())
2552 /* The target for some reason decided not to resume. */
2554 if (target_can_async_p ())
2555 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2559 /* We'll update this if & when we switch to a new thread. */
2560 previous_inferior_ptid
= inferior_ptid
;
2562 regcache
= get_current_regcache ();
2563 gdbarch
= get_regcache_arch (regcache
);
2564 aspace
= get_regcache_aspace (regcache
);
2565 pc
= regcache_read_pc (regcache
);
2566 tp
= inferior_thread ();
2569 step_start_function
= find_pc_function (pc
);
2571 stop_after_trap
= 1;
2573 /* Fill in with reasonable starting values. */
2574 init_thread_stepping_state (tp
);
2576 if (addr
== (CORE_ADDR
) -1)
2579 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
2580 && execution_direction
!= EXEC_REVERSE
)
2581 /* There is a breakpoint at the address we will resume at,
2582 step one instruction before inserting breakpoints so that
2583 we do not stop right away (and report a second hit at this
2586 Note, we don't do this in reverse, because we won't
2587 actually be executing the breakpoint insn anyway.
2588 We'll be (un-)executing the previous instruction. */
2589 tp
->stepping_over_breakpoint
= 1;
2590 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2591 && gdbarch_single_step_through_delay (gdbarch
,
2592 get_current_frame ()))
2593 /* We stepped onto an instruction that needs to be stepped
2594 again before re-inserting the breakpoint, do so. */
2595 tp
->stepping_over_breakpoint
= 1;
2599 regcache_write_pc (regcache
, addr
);
2602 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2603 tp
->suspend
.stop_signal
= siggnal
;
2605 /* Record the interpreter that issued the execution command that
2606 caused this thread to resume. If the top level interpreter is
2607 MI/async, and the execution command was a CLI command
2608 (next/step/etc.), we'll want to print stop event output to the MI
2609 console channel (the stepped-to line, etc.), as if the user
2610 entered the execution command on a real GDB console. */
2611 inferior_thread ()->control
.command_interp
= command_interp ();
2614 fprintf_unfiltered (gdb_stdlog
,
2615 "infrun: proceed (addr=%s, signal=%s, step=%d)\n",
2616 paddress (gdbarch
, addr
),
2617 gdb_signal_to_symbol_string (siggnal
), step
);
2620 /* In non-stop, each thread is handled individually. The context
2621 must already be set to the right thread here. */
2625 struct thread_info
*step_over
;
2627 /* In a multi-threaded task we may select another thread and
2628 then continue or step.
2630 But if the old thread was stopped at a breakpoint, it will
2631 immediately cause another breakpoint stop without any
2632 execution (i.e. it will report a breakpoint hit incorrectly).
2633 So we must step over it first.
2635 Look for a thread other than the current (TP) that reported a
2636 breakpoint hit and hasn't been resumed yet since. */
2637 step_over
= find_thread_needs_step_over (step
, tp
);
2638 if (step_over
!= NULL
)
2641 fprintf_unfiltered (gdb_stdlog
,
2642 "infrun: need to step-over [%s] first\n",
2643 target_pid_to_str (step_over
->ptid
));
2645 /* Store the prev_pc for the stepping thread too, needed by
2646 switch_back_to_stepping thread. */
2647 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2648 switch_to_thread (step_over
->ptid
);
2653 /* If we need to step over a breakpoint, and we're not using
2654 displaced stepping to do so, insert all breakpoints (watchpoints,
2655 etc.) but the one we're stepping over, step one instruction, and
2656 then re-insert the breakpoint when that step is finished. */
2657 if (tp
->stepping_over_breakpoint
&& !use_displaced_stepping (gdbarch
))
2659 struct regcache
*regcache
= get_current_regcache ();
2661 set_step_over_info (get_regcache_aspace (regcache
),
2662 regcache_read_pc (regcache
), 0);
2665 clear_step_over_info ();
2667 insert_breakpoints ();
2669 tp
->control
.trap_expected
= tp
->stepping_over_breakpoint
;
2671 annotate_starting ();
2673 /* Make sure that output from GDB appears before output from the
2675 gdb_flush (gdb_stdout
);
2677 /* Refresh prev_pc value just prior to resuming. This used to be
2678 done in stop_waiting, however, setting prev_pc there did not handle
2679 scenarios such as inferior function calls or returning from
2680 a function via the return command. In those cases, the prev_pc
2681 value was not set properly for subsequent commands. The prev_pc value
2682 is used to initialize the starting line number in the ecs. With an
2683 invalid value, the gdb next command ends up stopping at the position
2684 represented by the next line table entry past our start position.
2685 On platforms that generate one line table entry per line, this
2686 is not a problem. However, on the ia64, the compiler generates
2687 extraneous line table entries that do not increase the line number.
2688 When we issue the gdb next command on the ia64 after an inferior call
2689 or a return command, we often end up a few instructions forward, still
2690 within the original line we started.
2692 An attempt was made to refresh the prev_pc at the same time the
2693 execution_control_state is initialized (for instance, just before
2694 waiting for an inferior event). But this approach did not work
2695 because of platforms that use ptrace, where the pc register cannot
2696 be read unless the inferior is stopped. At that point, we are not
2697 guaranteed the inferior is stopped and so the regcache_read_pc() call
2698 can fail. Setting the prev_pc value here ensures the value is updated
2699 correctly when the inferior is stopped. */
2700 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2702 /* Resume inferior. */
2703 resume (tp
->control
.trap_expected
|| step
|| bpstat_should_step (),
2704 tp
->suspend
.stop_signal
);
2706 /* Wait for it to stop (if not standalone)
2707 and in any case decode why it stopped, and act accordingly. */
2708 /* Do this only if we are not using the event loop, or if the target
2709 does not support asynchronous execution. */
2710 if (!target_can_async_p ())
2712 wait_for_inferior ();
2718 /* Start remote-debugging of a machine over a serial link. */
2721 start_remote (int from_tty
)
2723 struct inferior
*inferior
;
2725 inferior
= current_inferior ();
2726 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2728 /* Always go on waiting for the target, regardless of the mode. */
2729 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2730 indicate to wait_for_inferior that a target should timeout if
2731 nothing is returned (instead of just blocking). Because of this,
2732 targets expecting an immediate response need to, internally, set
2733 things up so that the target_wait() is forced to eventually
2735 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2736 differentiate to its caller what the state of the target is after
2737 the initial open has been performed. Here we're assuming that
2738 the target has stopped. It should be possible to eventually have
2739 target_open() return to the caller an indication that the target
2740 is currently running and GDB state should be set to the same as
2741 for an async run. */
2742 wait_for_inferior ();
2744 /* Now that the inferior has stopped, do any bookkeeping like
2745 loading shared libraries. We want to do this before normal_stop,
2746 so that the displayed frame is up to date. */
2747 post_create_inferior (¤t_target
, from_tty
);
2752 /* Initialize static vars when a new inferior begins. */
2755 init_wait_for_inferior (void)
2757 /* These are meaningless until the first time through wait_for_inferior. */
2759 breakpoint_init_inferior (inf_starting
);
2761 clear_proceed_status (0);
2763 target_last_wait_ptid
= minus_one_ptid
;
2765 previous_inferior_ptid
= inferior_ptid
;
2767 /* Discard any skipped inlined frames. */
2768 clear_inline_frame_state (minus_one_ptid
);
2772 /* Data to be passed around while handling an event. This data is
2773 discarded between events. */
2774 struct execution_control_state
2777 /* The thread that got the event, if this was a thread event; NULL
2779 struct thread_info
*event_thread
;
2781 struct target_waitstatus ws
;
2782 int stop_func_filled_in
;
2783 CORE_ADDR stop_func_start
;
2784 CORE_ADDR stop_func_end
;
2785 const char *stop_func_name
;
2788 /* True if the event thread hit the single-step breakpoint of
2789 another thread. Thus the event doesn't cause a stop, the thread
2790 needs to be single-stepped past the single-step breakpoint before
2791 we can switch back to the original stepping thread. */
2792 int hit_singlestep_breakpoint
;
2795 static void handle_inferior_event (struct execution_control_state
*ecs
);
2797 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2798 struct execution_control_state
*ecs
);
2799 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2800 struct execution_control_state
*ecs
);
2801 static void handle_signal_stop (struct execution_control_state
*ecs
);
2802 static void check_exception_resume (struct execution_control_state
*,
2803 struct frame_info
*);
2805 static void end_stepping_range (struct execution_control_state
*ecs
);
2806 static void stop_waiting (struct execution_control_state
*ecs
);
2807 static void prepare_to_wait (struct execution_control_state
*ecs
);
2808 static void keep_going (struct execution_control_state
*ecs
);
2809 static void process_event_stop_test (struct execution_control_state
*ecs
);
2810 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
2812 /* Callback for iterate over threads. If the thread is stopped, but
2813 the user/frontend doesn't know about that yet, go through
2814 normal_stop, as if the thread had just stopped now. ARG points at
2815 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2816 ptid_is_pid(PTID) is true, applies to all threads of the process
2817 pointed at by PTID. Otherwise, apply only to the thread pointed by
2821 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2823 ptid_t ptid
= * (ptid_t
*) arg
;
2825 if ((ptid_equal (info
->ptid
, ptid
)
2826 || ptid_equal (minus_one_ptid
, ptid
)
2827 || (ptid_is_pid (ptid
)
2828 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2829 && is_running (info
->ptid
)
2830 && !is_executing (info
->ptid
))
2832 struct cleanup
*old_chain
;
2833 struct execution_control_state ecss
;
2834 struct execution_control_state
*ecs
= &ecss
;
2836 memset (ecs
, 0, sizeof (*ecs
));
2838 old_chain
= make_cleanup_restore_current_thread ();
2840 overlay_cache_invalid
= 1;
2841 /* Flush target cache before starting to handle each event.
2842 Target was running and cache could be stale. This is just a
2843 heuristic. Running threads may modify target memory, but we
2844 don't get any event. */
2845 target_dcache_invalidate ();
2847 /* Go through handle_inferior_event/normal_stop, so we always
2848 have consistent output as if the stop event had been
2850 ecs
->ptid
= info
->ptid
;
2851 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2852 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2853 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2855 handle_inferior_event (ecs
);
2857 if (!ecs
->wait_some_more
)
2859 struct thread_info
*tp
;
2863 /* Finish off the continuations. */
2864 tp
= inferior_thread ();
2865 do_all_intermediate_continuations_thread (tp
, 1);
2866 do_all_continuations_thread (tp
, 1);
2869 do_cleanups (old_chain
);
2875 /* This function is attached as a "thread_stop_requested" observer.
2876 Cleanup local state that assumed the PTID was to be resumed, and
2877 report the stop to the frontend. */
2880 infrun_thread_stop_requested (ptid_t ptid
)
2882 struct displaced_step_inferior_state
*displaced
;
2884 /* PTID was requested to stop. Remove it from the displaced
2885 stepping queue, so we don't try to resume it automatically. */
2887 for (displaced
= displaced_step_inferior_states
;
2889 displaced
= displaced
->next
)
2891 struct displaced_step_request
*it
, **prev_next_p
;
2893 it
= displaced
->step_request_queue
;
2894 prev_next_p
= &displaced
->step_request_queue
;
2897 if (ptid_match (it
->ptid
, ptid
))
2899 *prev_next_p
= it
->next
;
2905 prev_next_p
= &it
->next
;
2912 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2916 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2918 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2919 nullify_last_target_wait_ptid ();
2922 /* Delete the step resume, single-step and longjmp/exception resume
2923 breakpoints of TP. */
2926 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
2928 delete_step_resume_breakpoint (tp
);
2929 delete_exception_resume_breakpoint (tp
);
2930 delete_single_step_breakpoints (tp
);
2933 /* If the target still has execution, call FUNC for each thread that
2934 just stopped. In all-stop, that's all the non-exited threads; in
2935 non-stop, that's the current thread, only. */
2937 typedef void (*for_each_just_stopped_thread_callback_func
)
2938 (struct thread_info
*tp
);
2941 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
2943 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
2948 /* If in non-stop mode, only the current thread stopped. */
2949 func (inferior_thread ());
2953 struct thread_info
*tp
;
2955 /* In all-stop mode, all threads have stopped. */
2956 ALL_NON_EXITED_THREADS (tp
)
2963 /* Delete the step resume and longjmp/exception resume breakpoints of
2964 the threads that just stopped. */
2967 delete_just_stopped_threads_infrun_breakpoints (void)
2969 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
2972 /* Delete the single-step breakpoints of the threads that just
2976 delete_just_stopped_threads_single_step_breakpoints (void)
2978 for_each_just_stopped_thread (delete_single_step_breakpoints
);
2981 /* A cleanup wrapper. */
2984 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
2986 delete_just_stopped_threads_infrun_breakpoints ();
2989 /* Pretty print the results of target_wait, for debugging purposes. */
2992 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2993 const struct target_waitstatus
*ws
)
2995 char *status_string
= target_waitstatus_to_string (ws
);
2996 struct ui_file
*tmp_stream
= mem_fileopen ();
2999 /* The text is split over several lines because it was getting too long.
3000 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3001 output as a unit; we want only one timestamp printed if debug_timestamp
3004 fprintf_unfiltered (tmp_stream
,
3005 "infrun: target_wait (%d", ptid_get_pid (waiton_ptid
));
3006 if (ptid_get_pid (waiton_ptid
) != -1)
3007 fprintf_unfiltered (tmp_stream
,
3008 " [%s]", target_pid_to_str (waiton_ptid
));
3009 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3010 fprintf_unfiltered (tmp_stream
,
3011 "infrun: %d [%s],\n",
3012 ptid_get_pid (result_ptid
),
3013 target_pid_to_str (result_ptid
));
3014 fprintf_unfiltered (tmp_stream
,
3018 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3020 /* This uses %s in part to handle %'s in the text, but also to avoid
3021 a gcc error: the format attribute requires a string literal. */
3022 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3024 xfree (status_string
);
3026 ui_file_delete (tmp_stream
);
3029 /* Prepare and stabilize the inferior for detaching it. E.g.,
3030 detaching while a thread is displaced stepping is a recipe for
3031 crashing it, as nothing would readjust the PC out of the scratch
3035 prepare_for_detach (void)
3037 struct inferior
*inf
= current_inferior ();
3038 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3039 struct cleanup
*old_chain_1
;
3040 struct displaced_step_inferior_state
*displaced
;
3042 displaced
= get_displaced_stepping_state (inf
->pid
);
3044 /* Is any thread of this process displaced stepping? If not,
3045 there's nothing else to do. */
3046 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3050 fprintf_unfiltered (gdb_stdlog
,
3051 "displaced-stepping in-process while detaching");
3053 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3056 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3058 struct cleanup
*old_chain_2
;
3059 struct execution_control_state ecss
;
3060 struct execution_control_state
*ecs
;
3063 memset (ecs
, 0, sizeof (*ecs
));
3065 overlay_cache_invalid
= 1;
3066 /* Flush target cache before starting to handle each event.
3067 Target was running and cache could be stale. This is just a
3068 heuristic. Running threads may modify target memory, but we
3069 don't get any event. */
3070 target_dcache_invalidate ();
3072 if (deprecated_target_wait_hook
)
3073 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
3075 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
3078 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3080 /* If an error happens while handling the event, propagate GDB's
3081 knowledge of the executing state to the frontend/user running
3083 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3086 /* Now figure out what to do with the result of the result. */
3087 handle_inferior_event (ecs
);
3089 /* No error, don't finish the state yet. */
3090 discard_cleanups (old_chain_2
);
3092 /* Breakpoints and watchpoints are not installed on the target
3093 at this point, and signals are passed directly to the
3094 inferior, so this must mean the process is gone. */
3095 if (!ecs
->wait_some_more
)
3097 discard_cleanups (old_chain_1
);
3098 error (_("Program exited while detaching"));
3102 discard_cleanups (old_chain_1
);
3105 /* Wait for control to return from inferior to debugger.
3107 If inferior gets a signal, we may decide to start it up again
3108 instead of returning. That is why there is a loop in this function.
3109 When this function actually returns it means the inferior
3110 should be left stopped and GDB should read more commands. */
3113 wait_for_inferior (void)
3115 struct cleanup
*old_cleanups
;
3119 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3122 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3127 struct execution_control_state ecss
;
3128 struct execution_control_state
*ecs
= &ecss
;
3129 struct cleanup
*old_chain
;
3130 ptid_t waiton_ptid
= minus_one_ptid
;
3132 memset (ecs
, 0, sizeof (*ecs
));
3134 overlay_cache_invalid
= 1;
3136 /* Flush target cache before starting to handle each event.
3137 Target was running and cache could be stale. This is just a
3138 heuristic. Running threads may modify target memory, but we
3139 don't get any event. */
3140 target_dcache_invalidate ();
3142 if (deprecated_target_wait_hook
)
3143 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
3145 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
3148 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3150 /* If an error happens while handling the event, propagate GDB's
3151 knowledge of the executing state to the frontend/user running
3153 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3155 /* Now figure out what to do with the result of the result. */
3156 handle_inferior_event (ecs
);
3158 /* No error, don't finish the state yet. */
3159 discard_cleanups (old_chain
);
3161 if (!ecs
->wait_some_more
)
3165 do_cleanups (old_cleanups
);
3168 /* Cleanup that reinstalls the readline callback handler, if the
3169 target is running in the background. If while handling the target
3170 event something triggered a secondary prompt, like e.g., a
3171 pagination prompt, we'll have removed the callback handler (see
3172 gdb_readline_wrapper_line). Need to do this as we go back to the
3173 event loop, ready to process further input. Note this has no
3174 effect if the handler hasn't actually been removed, because calling
3175 rl_callback_handler_install resets the line buffer, thus losing
3179 reinstall_readline_callback_handler_cleanup (void *arg
)
3181 if (async_command_editing_p
&& !sync_execution
)
3182 gdb_rl_callback_handler_reinstall ();
3185 /* Asynchronous version of wait_for_inferior. It is called by the
3186 event loop whenever a change of state is detected on the file
3187 descriptor corresponding to the target. It can be called more than
3188 once to complete a single execution command. In such cases we need
3189 to keep the state in a global variable ECSS. If it is the last time
3190 that this function is called for a single execution command, then
3191 report to the user that the inferior has stopped, and do the
3192 necessary cleanups. */
3195 fetch_inferior_event (void *client_data
)
3197 struct execution_control_state ecss
;
3198 struct execution_control_state
*ecs
= &ecss
;
3199 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3200 struct cleanup
*ts_old_chain
;
3201 int was_sync
= sync_execution
;
3203 ptid_t waiton_ptid
= minus_one_ptid
;
3205 memset (ecs
, 0, sizeof (*ecs
));
3207 /* End up with readline processing input, if necessary. */
3208 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3210 /* We're handling a live event, so make sure we're doing live
3211 debugging. If we're looking at traceframes while the target is
3212 running, we're going to need to get back to that mode after
3213 handling the event. */
3216 make_cleanup_restore_current_traceframe ();
3217 set_current_traceframe (-1);
3221 /* In non-stop mode, the user/frontend should not notice a thread
3222 switch due to internal events. Make sure we reverse to the
3223 user selected thread and frame after handling the event and
3224 running any breakpoint commands. */
3225 make_cleanup_restore_current_thread ();
3227 overlay_cache_invalid
= 1;
3228 /* Flush target cache before starting to handle each event. Target
3229 was running and cache could be stale. This is just a heuristic.
3230 Running threads may modify target memory, but we don't get any
3232 target_dcache_invalidate ();
3234 make_cleanup_restore_integer (&execution_direction
);
3235 execution_direction
= target_execution_direction ();
3237 if (deprecated_target_wait_hook
)
3239 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3241 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3244 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3246 /* If an error happens while handling the event, propagate GDB's
3247 knowledge of the executing state to the frontend/user running
3250 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3252 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3254 /* Get executed before make_cleanup_restore_current_thread above to apply
3255 still for the thread which has thrown the exception. */
3256 make_bpstat_clear_actions_cleanup ();
3258 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3260 /* Now figure out what to do with the result of the result. */
3261 handle_inferior_event (ecs
);
3263 if (!ecs
->wait_some_more
)
3265 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3267 delete_just_stopped_threads_infrun_breakpoints ();
3269 /* We may not find an inferior if this was a process exit. */
3270 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3273 if (target_has_execution
3274 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
3275 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3276 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3277 && ecs
->event_thread
->step_multi
3278 && ecs
->event_thread
->control
.stop_step
)
3279 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
3282 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3287 /* No error, don't finish the thread states yet. */
3288 discard_cleanups (ts_old_chain
);
3290 /* Revert thread and frame. */
3291 do_cleanups (old_chain
);
3293 /* If the inferior was in sync execution mode, and now isn't,
3294 restore the prompt (a synchronous execution command has finished,
3295 and we're ready for input). */
3296 if (interpreter_async
&& was_sync
&& !sync_execution
)
3297 observer_notify_sync_execution_done ();
3301 && exec_done_display_p
3302 && (ptid_equal (inferior_ptid
, null_ptid
)
3303 || !is_running (inferior_ptid
)))
3304 printf_unfiltered (_("completed.\n"));
3307 /* Record the frame and location we're currently stepping through. */
3309 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3311 struct thread_info
*tp
= inferior_thread ();
3313 tp
->control
.step_frame_id
= get_frame_id (frame
);
3314 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3316 tp
->current_symtab
= sal
.symtab
;
3317 tp
->current_line
= sal
.line
;
3320 /* Clear context switchable stepping state. */
3323 init_thread_stepping_state (struct thread_info
*tss
)
3325 tss
->stepped_breakpoint
= 0;
3326 tss
->stepping_over_breakpoint
= 0;
3327 tss
->stepping_over_watchpoint
= 0;
3328 tss
->step_after_step_resume_breakpoint
= 0;
3331 /* Set the cached copy of the last ptid/waitstatus. */
3334 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3336 target_last_wait_ptid
= ptid
;
3337 target_last_waitstatus
= status
;
3340 /* Return the cached copy of the last pid/waitstatus returned by
3341 target_wait()/deprecated_target_wait_hook(). The data is actually
3342 cached by handle_inferior_event(), which gets called immediately
3343 after target_wait()/deprecated_target_wait_hook(). */
3346 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3348 *ptidp
= target_last_wait_ptid
;
3349 *status
= target_last_waitstatus
;
3353 nullify_last_target_wait_ptid (void)
3355 target_last_wait_ptid
= minus_one_ptid
;
3358 /* Switch thread contexts. */
3361 context_switch (ptid_t ptid
)
3363 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
3365 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3366 target_pid_to_str (inferior_ptid
));
3367 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3368 target_pid_to_str (ptid
));
3371 switch_to_thread (ptid
);
3375 adjust_pc_after_break (struct execution_control_state
*ecs
)
3377 struct regcache
*regcache
;
3378 struct gdbarch
*gdbarch
;
3379 struct address_space
*aspace
;
3380 CORE_ADDR breakpoint_pc
, decr_pc
;
3382 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3383 we aren't, just return.
3385 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3386 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3387 implemented by software breakpoints should be handled through the normal
3390 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3391 different signals (SIGILL or SIGEMT for instance), but it is less
3392 clear where the PC is pointing afterwards. It may not match
3393 gdbarch_decr_pc_after_break. I don't know any specific target that
3394 generates these signals at breakpoints (the code has been in GDB since at
3395 least 1992) so I can not guess how to handle them here.
3397 In earlier versions of GDB, a target with
3398 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3399 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3400 target with both of these set in GDB history, and it seems unlikely to be
3401 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3403 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
3406 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
3409 /* In reverse execution, when a breakpoint is hit, the instruction
3410 under it has already been de-executed. The reported PC always
3411 points at the breakpoint address, so adjusting it further would
3412 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3415 B1 0x08000000 : INSN1
3416 B2 0x08000001 : INSN2
3418 PC -> 0x08000003 : INSN4
3420 Say you're stopped at 0x08000003 as above. Reverse continuing
3421 from that point should hit B2 as below. Reading the PC when the
3422 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3423 been de-executed already.
3425 B1 0x08000000 : INSN1
3426 B2 PC -> 0x08000001 : INSN2
3430 We can't apply the same logic as for forward execution, because
3431 we would wrongly adjust the PC to 0x08000000, since there's a
3432 breakpoint at PC - 1. We'd then report a hit on B1, although
3433 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3435 if (execution_direction
== EXEC_REVERSE
)
3438 /* If this target does not decrement the PC after breakpoints, then
3439 we have nothing to do. */
3440 regcache
= get_thread_regcache (ecs
->ptid
);
3441 gdbarch
= get_regcache_arch (regcache
);
3443 decr_pc
= target_decr_pc_after_break (gdbarch
);
3447 aspace
= get_regcache_aspace (regcache
);
3449 /* Find the location where (if we've hit a breakpoint) the
3450 breakpoint would be. */
3451 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3453 /* Check whether there actually is a software breakpoint inserted at
3456 If in non-stop mode, a race condition is possible where we've
3457 removed a breakpoint, but stop events for that breakpoint were
3458 already queued and arrive later. To suppress those spurious
3459 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3460 and retire them after a number of stop events are reported. */
3461 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3462 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3464 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
3466 if (record_full_is_used ())
3467 record_full_gdb_operation_disable_set ();
3469 /* When using hardware single-step, a SIGTRAP is reported for both
3470 a completed single-step and a software breakpoint. Need to
3471 differentiate between the two, as the latter needs adjusting
3472 but the former does not.
3474 The SIGTRAP can be due to a completed hardware single-step only if
3475 - we didn't insert software single-step breakpoints
3476 - the thread to be examined is still the current thread
3477 - this thread is currently being stepped
3479 If any of these events did not occur, we must have stopped due
3480 to hitting a software breakpoint, and have to back up to the
3483 As a special case, we could have hardware single-stepped a
3484 software breakpoint. In this case (prev_pc == breakpoint_pc),
3485 we also need to back up to the breakpoint address. */
3487 if (thread_has_single_step_breakpoints_set (ecs
->event_thread
)
3488 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
3489 || !currently_stepping (ecs
->event_thread
)
3490 || (ecs
->event_thread
->stepped_breakpoint
3491 && ecs
->event_thread
->prev_pc
== breakpoint_pc
))
3492 regcache_write_pc (regcache
, breakpoint_pc
);
3494 do_cleanups (old_cleanups
);
3499 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3501 for (frame
= get_prev_frame (frame
);
3503 frame
= get_prev_frame (frame
))
3505 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3507 if (get_frame_type (frame
) != INLINE_FRAME
)
3514 /* Auxiliary function that handles syscall entry/return events.
3515 It returns 1 if the inferior should keep going (and GDB
3516 should ignore the event), or 0 if the event deserves to be
3520 handle_syscall_event (struct execution_control_state
*ecs
)
3522 struct regcache
*regcache
;
3525 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3526 context_switch (ecs
->ptid
);
3528 regcache
= get_thread_regcache (ecs
->ptid
);
3529 syscall_number
= ecs
->ws
.value
.syscall_number
;
3530 stop_pc
= regcache_read_pc (regcache
);
3532 if (catch_syscall_enabled () > 0
3533 && catching_syscall_number (syscall_number
) > 0)
3536 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3539 ecs
->event_thread
->control
.stop_bpstat
3540 = bpstat_stop_status (get_regcache_aspace (regcache
),
3541 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3543 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3545 /* Catchpoint hit. */
3550 /* If no catchpoint triggered for this, then keep going. */
3555 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3558 fill_in_stop_func (struct gdbarch
*gdbarch
,
3559 struct execution_control_state
*ecs
)
3561 if (!ecs
->stop_func_filled_in
)
3563 /* Don't care about return value; stop_func_start and stop_func_name
3564 will both be 0 if it doesn't work. */
3565 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3566 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3567 ecs
->stop_func_start
3568 += gdbarch_deprecated_function_start_offset (gdbarch
);
3570 if (gdbarch_skip_entrypoint_p (gdbarch
))
3571 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
3572 ecs
->stop_func_start
);
3574 ecs
->stop_func_filled_in
= 1;
3579 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
3581 static enum stop_kind
3582 get_inferior_stop_soon (ptid_t ptid
)
3584 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ptid
));
3586 gdb_assert (inf
!= NULL
);
3587 return inf
->control
.stop_soon
;
3590 /* Given an execution control state that has been freshly filled in by
3591 an event from the inferior, figure out what it means and take
3594 The alternatives are:
3596 1) stop_waiting and return; to really stop and return to the
3599 2) keep_going and return; to wait for the next event (set
3600 ecs->event_thread->stepping_over_breakpoint to 1 to single step
3604 handle_inferior_event (struct execution_control_state
*ecs
)
3606 enum stop_kind stop_soon
;
3608 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3610 /* We had an event in the inferior, but we are not interested in
3611 handling it at this level. The lower layers have already
3612 done what needs to be done, if anything.
3614 One of the possible circumstances for this is when the
3615 inferior produces output for the console. The inferior has
3616 not stopped, and we are ignoring the event. Another possible
3617 circumstance is any event which the lower level knows will be
3618 reported multiple times without an intervening resume. */
3620 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3621 prepare_to_wait (ecs
);
3625 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3626 && target_can_async_p () && !sync_execution
)
3628 /* There were no unwaited-for children left in the target, but,
3629 we're not synchronously waiting for events either. Just
3630 ignore. Otherwise, if we were running a synchronous
3631 execution command, we need to cancel it and give the user
3632 back the terminal. */
3634 fprintf_unfiltered (gdb_stdlog
,
3635 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3636 prepare_to_wait (ecs
);
3640 /* Cache the last pid/waitstatus. */
3641 set_last_target_status (ecs
->ptid
, ecs
->ws
);
3643 /* Always clear state belonging to the previous time we stopped. */
3644 stop_stack_dummy
= STOP_NONE
;
3646 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3648 /* No unwaited-for children left. IOW, all resumed children
3651 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3653 stop_print_frame
= 0;
3658 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3659 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3661 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3662 /* If it's a new thread, add it to the thread database. */
3663 if (ecs
->event_thread
== NULL
)
3664 ecs
->event_thread
= add_thread (ecs
->ptid
);
3666 /* Disable range stepping. If the next step request could use a
3667 range, this will be end up re-enabled then. */
3668 ecs
->event_thread
->control
.may_range_step
= 0;
3671 /* Dependent on valid ECS->EVENT_THREAD. */
3672 adjust_pc_after_break (ecs
);
3674 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3675 reinit_frame_cache ();
3677 breakpoint_retire_moribund ();
3679 /* First, distinguish signals caused by the debugger from signals
3680 that have to do with the program's own actions. Note that
3681 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3682 on the operating system version. Here we detect when a SIGILL or
3683 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3684 something similar for SIGSEGV, since a SIGSEGV will be generated
3685 when we're trying to execute a breakpoint instruction on a
3686 non-executable stack. This happens for call dummy breakpoints
3687 for architectures like SPARC that place call dummies on the
3689 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3690 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3691 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3692 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3694 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3696 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3697 regcache_read_pc (regcache
)))
3700 fprintf_unfiltered (gdb_stdlog
,
3701 "infrun: Treating signal as SIGTRAP\n");
3702 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3706 /* Mark the non-executing threads accordingly. In all-stop, all
3707 threads of all processes are stopped when we get any event
3708 reported. In non-stop mode, only the event thread stops. If
3709 we're handling a process exit in non-stop mode, there's nothing
3710 to do, as threads of the dead process are gone, and threads of
3711 any other process were left running. */
3713 set_executing (minus_one_ptid
, 0);
3714 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3715 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3716 set_executing (ecs
->ptid
, 0);
3718 switch (ecs
->ws
.kind
)
3720 case TARGET_WAITKIND_LOADED
:
3722 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3723 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3724 context_switch (ecs
->ptid
);
3725 /* Ignore gracefully during startup of the inferior, as it might
3726 be the shell which has just loaded some objects, otherwise
3727 add the symbols for the newly loaded objects. Also ignore at
3728 the beginning of an attach or remote session; we will query
3729 the full list of libraries once the connection is
3732 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
3733 if (stop_soon
== NO_STOP_QUIETLY
)
3735 struct regcache
*regcache
;
3737 regcache
= get_thread_regcache (ecs
->ptid
);
3739 handle_solib_event ();
3741 ecs
->event_thread
->control
.stop_bpstat
3742 = bpstat_stop_status (get_regcache_aspace (regcache
),
3743 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3745 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3747 /* A catchpoint triggered. */
3748 process_event_stop_test (ecs
);
3752 /* If requested, stop when the dynamic linker notifies
3753 gdb of events. This allows the user to get control
3754 and place breakpoints in initializer routines for
3755 dynamically loaded objects (among other things). */
3756 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3757 if (stop_on_solib_events
)
3759 /* Make sure we print "Stopped due to solib-event" in
3761 stop_print_frame
= 1;
3768 /* If we are skipping through a shell, or through shared library
3769 loading that we aren't interested in, resume the program. If
3770 we're running the program normally, also resume. */
3771 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3773 /* Loading of shared libraries might have changed breakpoint
3774 addresses. Make sure new breakpoints are inserted. */
3775 if (stop_soon
== NO_STOP_QUIETLY
)
3776 insert_breakpoints ();
3777 resume (0, GDB_SIGNAL_0
);
3778 prepare_to_wait (ecs
);
3782 /* But stop if we're attaching or setting up a remote
3784 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3785 || stop_soon
== STOP_QUIETLY_REMOTE
)
3788 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3793 internal_error (__FILE__
, __LINE__
,
3794 _("unhandled stop_soon: %d"), (int) stop_soon
);
3796 case TARGET_WAITKIND_SPURIOUS
:
3798 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3799 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3800 context_switch (ecs
->ptid
);
3801 resume (0, GDB_SIGNAL_0
);
3802 prepare_to_wait (ecs
);
3805 case TARGET_WAITKIND_EXITED
:
3806 case TARGET_WAITKIND_SIGNALLED
:
3809 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3810 fprintf_unfiltered (gdb_stdlog
,
3811 "infrun: TARGET_WAITKIND_EXITED\n");
3813 fprintf_unfiltered (gdb_stdlog
,
3814 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3817 inferior_ptid
= ecs
->ptid
;
3818 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3819 set_current_program_space (current_inferior ()->pspace
);
3820 handle_vfork_child_exec_or_exit (0);
3821 target_terminal_ours (); /* Must do this before mourn anyway. */
3823 /* Clearing any previous state of convenience variables. */
3824 clear_exit_convenience_vars ();
3826 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3828 /* Record the exit code in the convenience variable $_exitcode, so
3829 that the user can inspect this again later. */
3830 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3831 (LONGEST
) ecs
->ws
.value
.integer
);
3833 /* Also record this in the inferior itself. */
3834 current_inferior ()->has_exit_code
= 1;
3835 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3837 /* Support the --return-child-result option. */
3838 return_child_result_value
= ecs
->ws
.value
.integer
;
3840 observer_notify_exited (ecs
->ws
.value
.integer
);
3844 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3845 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3847 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
3849 /* Set the value of the internal variable $_exitsignal,
3850 which holds the signal uncaught by the inferior. */
3851 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
3852 gdbarch_gdb_signal_to_target (gdbarch
,
3853 ecs
->ws
.value
.sig
));
3857 /* We don't have access to the target's method used for
3858 converting between signal numbers (GDB's internal
3859 representation <-> target's representation).
3860 Therefore, we cannot do a good job at displaying this
3861 information to the user. It's better to just warn
3862 her about it (if infrun debugging is enabled), and
3865 fprintf_filtered (gdb_stdlog
, _("\
3866 Cannot fill $_exitsignal with the correct signal number.\n"));
3869 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
3872 gdb_flush (gdb_stdout
);
3873 target_mourn_inferior ();
3874 stop_print_frame
= 0;
3878 /* The following are the only cases in which we keep going;
3879 the above cases end in a continue or goto. */
3880 case TARGET_WAITKIND_FORKED
:
3881 case TARGET_WAITKIND_VFORKED
:
3884 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3885 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3887 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
3890 /* Check whether the inferior is displaced stepping. */
3892 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3893 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3894 struct displaced_step_inferior_state
*displaced
3895 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3897 /* If checking displaced stepping is supported, and thread
3898 ecs->ptid is displaced stepping. */
3899 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3901 struct inferior
*parent_inf
3902 = find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3903 struct regcache
*child_regcache
;
3904 CORE_ADDR parent_pc
;
3906 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3907 indicating that the displaced stepping of syscall instruction
3908 has been done. Perform cleanup for parent process here. Note
3909 that this operation also cleans up the child process for vfork,
3910 because their pages are shared. */
3911 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3913 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3915 /* Restore scratch pad for child process. */
3916 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3919 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3920 the child's PC is also within the scratchpad. Set the child's PC
3921 to the parent's PC value, which has already been fixed up.
3922 FIXME: we use the parent's aspace here, although we're touching
3923 the child, because the child hasn't been added to the inferior
3924 list yet at this point. */
3927 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3929 parent_inf
->aspace
);
3930 /* Read PC value of parent process. */
3931 parent_pc
= regcache_read_pc (regcache
);
3933 if (debug_displaced
)
3934 fprintf_unfiltered (gdb_stdlog
,
3935 "displaced: write child pc from %s to %s\n",
3937 regcache_read_pc (child_regcache
)),
3938 paddress (gdbarch
, parent_pc
));
3940 regcache_write_pc (child_regcache
, parent_pc
);
3944 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3945 context_switch (ecs
->ptid
);
3947 /* Immediately detach breakpoints from the child before there's
3948 any chance of letting the user delete breakpoints from the
3949 breakpoint lists. If we don't do this early, it's easy to
3950 leave left over traps in the child, vis: "break foo; catch
3951 fork; c; <fork>; del; c; <child calls foo>". We only follow
3952 the fork on the last `continue', and by that time the
3953 breakpoint at "foo" is long gone from the breakpoint table.
3954 If we vforked, then we don't need to unpatch here, since both
3955 parent and child are sharing the same memory pages; we'll
3956 need to unpatch at follow/detach time instead to be certain
3957 that new breakpoints added between catchpoint hit time and
3958 vfork follow are detached. */
3959 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3961 /* This won't actually modify the breakpoint list, but will
3962 physically remove the breakpoints from the child. */
3963 detach_breakpoints (ecs
->ws
.value
.related_pid
);
3966 delete_just_stopped_threads_single_step_breakpoints ();
3968 /* In case the event is caught by a catchpoint, remember that
3969 the event is to be followed at the next resume of the thread,
3970 and not immediately. */
3971 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3973 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3975 ecs
->event_thread
->control
.stop_bpstat
3976 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3977 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3979 /* If no catchpoint triggered for this, then keep going. Note
3980 that we're interested in knowing the bpstat actually causes a
3981 stop, not just if it may explain the signal. Software
3982 watchpoints, for example, always appear in the bpstat. */
3983 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3989 = (follow_fork_mode_string
== follow_fork_mode_child
);
3991 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3993 should_resume
= follow_fork ();
3996 child
= ecs
->ws
.value
.related_pid
;
3998 /* In non-stop mode, also resume the other branch. */
3999 if (non_stop
&& !detach_fork
)
4002 switch_to_thread (parent
);
4004 switch_to_thread (child
);
4006 ecs
->event_thread
= inferior_thread ();
4007 ecs
->ptid
= inferior_ptid
;
4012 switch_to_thread (child
);
4014 switch_to_thread (parent
);
4016 ecs
->event_thread
= inferior_thread ();
4017 ecs
->ptid
= inferior_ptid
;
4025 process_event_stop_test (ecs
);
4028 case TARGET_WAITKIND_VFORK_DONE
:
4029 /* Done with the shared memory region. Re-insert breakpoints in
4030 the parent, and keep going. */
4033 fprintf_unfiltered (gdb_stdlog
,
4034 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
4036 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4037 context_switch (ecs
->ptid
);
4039 current_inferior ()->waiting_for_vfork_done
= 0;
4040 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
4041 /* This also takes care of reinserting breakpoints in the
4042 previously locked inferior. */
4046 case TARGET_WAITKIND_EXECD
:
4048 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
4050 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4051 context_switch (ecs
->ptid
);
4053 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4055 /* Do whatever is necessary to the parent branch of the vfork. */
4056 handle_vfork_child_exec_or_exit (1);
4058 /* This causes the eventpoints and symbol table to be reset.
4059 Must do this now, before trying to determine whether to
4061 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
4063 ecs
->event_thread
->control
.stop_bpstat
4064 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4065 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4067 /* Note that this may be referenced from inside
4068 bpstat_stop_status above, through inferior_has_execd. */
4069 xfree (ecs
->ws
.value
.execd_pathname
);
4070 ecs
->ws
.value
.execd_pathname
= NULL
;
4072 /* If no catchpoint triggered for this, then keep going. */
4073 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4075 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4079 process_event_stop_test (ecs
);
4082 /* Be careful not to try to gather much state about a thread
4083 that's in a syscall. It's frequently a losing proposition. */
4084 case TARGET_WAITKIND_SYSCALL_ENTRY
:
4086 fprintf_unfiltered (gdb_stdlog
,
4087 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
4088 /* Getting the current syscall number. */
4089 if (handle_syscall_event (ecs
) == 0)
4090 process_event_stop_test (ecs
);
4093 /* Before examining the threads further, step this thread to
4094 get it entirely out of the syscall. (We get notice of the
4095 event when the thread is just on the verge of exiting a
4096 syscall. Stepping one instruction seems to get it back
4098 case TARGET_WAITKIND_SYSCALL_RETURN
:
4100 fprintf_unfiltered (gdb_stdlog
,
4101 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
4102 if (handle_syscall_event (ecs
) == 0)
4103 process_event_stop_test (ecs
);
4106 case TARGET_WAITKIND_STOPPED
:
4108 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
4109 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
4110 handle_signal_stop (ecs
);
4113 case TARGET_WAITKIND_NO_HISTORY
:
4115 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
4116 /* Reverse execution: target ran out of history info. */
4118 delete_just_stopped_threads_single_step_breakpoints ();
4119 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4120 observer_notify_no_history ();
4126 /* Come here when the program has stopped with a signal. */
4129 handle_signal_stop (struct execution_control_state
*ecs
)
4131 struct frame_info
*frame
;
4132 struct gdbarch
*gdbarch
;
4133 int stopped_by_watchpoint
;
4134 enum stop_kind stop_soon
;
4137 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
4139 /* Do we need to clean up the state of a thread that has
4140 completed a displaced single-step? (Doing so usually affects
4141 the PC, so do it here, before we set stop_pc.) */
4142 displaced_step_fixup (ecs
->ptid
,
4143 ecs
->event_thread
->suspend
.stop_signal
);
4145 /* If we either finished a single-step or hit a breakpoint, but
4146 the user wanted this thread to be stopped, pretend we got a
4147 SIG0 (generic unsignaled stop). */
4148 if (ecs
->event_thread
->stop_requested
4149 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4150 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4152 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4156 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4157 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4158 struct cleanup
*old_chain
= save_inferior_ptid ();
4160 inferior_ptid
= ecs
->ptid
;
4162 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
4163 paddress (gdbarch
, stop_pc
));
4164 if (target_stopped_by_watchpoint ())
4168 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
4170 if (target_stopped_data_address (¤t_target
, &addr
))
4171 fprintf_unfiltered (gdb_stdlog
,
4172 "infrun: stopped data address = %s\n",
4173 paddress (gdbarch
, addr
));
4175 fprintf_unfiltered (gdb_stdlog
,
4176 "infrun: (no data address available)\n");
4179 do_cleanups (old_chain
);
4182 /* This is originated from start_remote(), start_inferior() and
4183 shared libraries hook functions. */
4184 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4185 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4187 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4188 context_switch (ecs
->ptid
);
4190 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4191 stop_print_frame
= 1;
4196 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4199 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4200 context_switch (ecs
->ptid
);
4202 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4203 stop_print_frame
= 0;
4208 /* This originates from attach_command(). We need to overwrite
4209 the stop_signal here, because some kernels don't ignore a
4210 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4211 See more comments in inferior.h. On the other hand, if we
4212 get a non-SIGSTOP, report it to the user - assume the backend
4213 will handle the SIGSTOP if it should show up later.
4215 Also consider that the attach is complete when we see a
4216 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4217 target extended-remote report it instead of a SIGSTOP
4218 (e.g. gdbserver). We already rely on SIGTRAP being our
4219 signal, so this is no exception.
4221 Also consider that the attach is complete when we see a
4222 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4223 the target to stop all threads of the inferior, in case the
4224 low level attach operation doesn't stop them implicitly. If
4225 they weren't stopped implicitly, then the stub will report a
4226 GDB_SIGNAL_0, meaning: stopped for no particular reason
4227 other than GDB's request. */
4228 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4229 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4230 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4231 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4233 stop_print_frame
= 1;
4235 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4239 /* See if something interesting happened to the non-current thread. If
4240 so, then switch to that thread. */
4241 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4244 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
4246 context_switch (ecs
->ptid
);
4248 if (deprecated_context_hook
)
4249 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
4252 /* At this point, get hold of the now-current thread's frame. */
4253 frame
= get_current_frame ();
4254 gdbarch
= get_frame_arch (frame
);
4256 /* Pull the single step breakpoints out of the target. */
4257 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4259 struct regcache
*regcache
;
4260 struct address_space
*aspace
;
4263 regcache
= get_thread_regcache (ecs
->ptid
);
4264 aspace
= get_regcache_aspace (regcache
);
4265 pc
= regcache_read_pc (regcache
);
4267 /* However, before doing so, if this single-step breakpoint was
4268 actually for another thread, set this thread up for moving
4270 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
4273 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
4277 fprintf_unfiltered (gdb_stdlog
,
4278 "infrun: [%s] hit another thread's "
4279 "single-step breakpoint\n",
4280 target_pid_to_str (ecs
->ptid
));
4282 ecs
->hit_singlestep_breakpoint
= 1;
4289 fprintf_unfiltered (gdb_stdlog
,
4290 "infrun: [%s] hit its "
4291 "single-step breakpoint\n",
4292 target_pid_to_str (ecs
->ptid
));
4296 delete_just_stopped_threads_single_step_breakpoints ();
4298 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4299 && ecs
->event_thread
->control
.trap_expected
4300 && ecs
->event_thread
->stepping_over_watchpoint
)
4301 stopped_by_watchpoint
= 0;
4303 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4305 /* If necessary, step over this watchpoint. We'll be back to display
4307 if (stopped_by_watchpoint
4308 && (target_have_steppable_watchpoint
4309 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4311 /* At this point, we are stopped at an instruction which has
4312 attempted to write to a piece of memory under control of
4313 a watchpoint. The instruction hasn't actually executed
4314 yet. If we were to evaluate the watchpoint expression
4315 now, we would get the old value, and therefore no change
4316 would seem to have occurred.
4318 In order to make watchpoints work `right', we really need
4319 to complete the memory write, and then evaluate the
4320 watchpoint expression. We do this by single-stepping the
4323 It may not be necessary to disable the watchpoint to step over
4324 it. For example, the PA can (with some kernel cooperation)
4325 single step over a watchpoint without disabling the watchpoint.
4327 It is far more common to need to disable a watchpoint to step
4328 the inferior over it. If we have non-steppable watchpoints,
4329 we must disable the current watchpoint; it's simplest to
4330 disable all watchpoints.
4332 Any breakpoint at PC must also be stepped over -- if there's
4333 one, it will have already triggered before the watchpoint
4334 triggered, and we either already reported it to the user, or
4335 it didn't cause a stop and we called keep_going. In either
4336 case, if there was a breakpoint at PC, we must be trying to
4338 ecs
->event_thread
->stepping_over_watchpoint
= 1;
4343 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4344 ecs
->event_thread
->stepping_over_watchpoint
= 0;
4345 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4346 ecs
->event_thread
->control
.stop_step
= 0;
4347 stop_print_frame
= 1;
4348 stopped_by_random_signal
= 0;
4350 /* Hide inlined functions starting here, unless we just performed stepi or
4351 nexti. After stepi and nexti, always show the innermost frame (not any
4352 inline function call sites). */
4353 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4355 struct address_space
*aspace
=
4356 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4358 /* skip_inline_frames is expensive, so we avoid it if we can
4359 determine that the address is one where functions cannot have
4360 been inlined. This improves performance with inferiors that
4361 load a lot of shared libraries, because the solib event
4362 breakpoint is defined as the address of a function (i.e. not
4363 inline). Note that we have to check the previous PC as well
4364 as the current one to catch cases when we have just
4365 single-stepped off a breakpoint prior to reinstating it.
4366 Note that we're assuming that the code we single-step to is
4367 not inline, but that's not definitive: there's nothing
4368 preventing the event breakpoint function from containing
4369 inlined code, and the single-step ending up there. If the
4370 user had set a breakpoint on that inlined code, the missing
4371 skip_inline_frames call would break things. Fortunately
4372 that's an extremely unlikely scenario. */
4373 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4374 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4375 && ecs
->event_thread
->control
.trap_expected
4376 && pc_at_non_inline_function (aspace
,
4377 ecs
->event_thread
->prev_pc
,
4380 skip_inline_frames (ecs
->ptid
);
4382 /* Re-fetch current thread's frame in case that invalidated
4384 frame
= get_current_frame ();
4385 gdbarch
= get_frame_arch (frame
);
4389 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4390 && ecs
->event_thread
->control
.trap_expected
4391 && gdbarch_single_step_through_delay_p (gdbarch
)
4392 && currently_stepping (ecs
->event_thread
))
4394 /* We're trying to step off a breakpoint. Turns out that we're
4395 also on an instruction that needs to be stepped multiple
4396 times before it's been fully executing. E.g., architectures
4397 with a delay slot. It needs to be stepped twice, once for
4398 the instruction and once for the delay slot. */
4399 int step_through_delay
4400 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4402 if (debug_infrun
&& step_through_delay
)
4403 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4404 if (ecs
->event_thread
->control
.step_range_end
== 0
4405 && step_through_delay
)
4407 /* The user issued a continue when stopped at a breakpoint.
4408 Set up for another trap and get out of here. */
4409 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4413 else if (step_through_delay
)
4415 /* The user issued a step when stopped at a breakpoint.
4416 Maybe we should stop, maybe we should not - the delay
4417 slot *might* correspond to a line of source. In any
4418 case, don't decide that here, just set
4419 ecs->stepping_over_breakpoint, making sure we
4420 single-step again before breakpoints are re-inserted. */
4421 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4425 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4426 handles this event. */
4427 ecs
->event_thread
->control
.stop_bpstat
4428 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4429 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4431 /* Following in case break condition called a
4433 stop_print_frame
= 1;
4435 /* This is where we handle "moribund" watchpoints. Unlike
4436 software breakpoints traps, hardware watchpoint traps are
4437 always distinguishable from random traps. If no high-level
4438 watchpoint is associated with the reported stop data address
4439 anymore, then the bpstat does not explain the signal ---
4440 simply make sure to ignore it if `stopped_by_watchpoint' is
4444 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4445 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4447 && stopped_by_watchpoint
)
4448 fprintf_unfiltered (gdb_stdlog
,
4449 "infrun: no user watchpoint explains "
4450 "watchpoint SIGTRAP, ignoring\n");
4452 /* NOTE: cagney/2003-03-29: These checks for a random signal
4453 at one stage in the past included checks for an inferior
4454 function call's call dummy's return breakpoint. The original
4455 comment, that went with the test, read:
4457 ``End of a stack dummy. Some systems (e.g. Sony news) give
4458 another signal besides SIGTRAP, so check here as well as
4461 If someone ever tries to get call dummys on a
4462 non-executable stack to work (where the target would stop
4463 with something like a SIGSEGV), then those tests might need
4464 to be re-instated. Given, however, that the tests were only
4465 enabled when momentary breakpoints were not being used, I
4466 suspect that it won't be the case.
4468 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4469 be necessary for call dummies on a non-executable stack on
4472 /* See if the breakpoints module can explain the signal. */
4474 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4475 ecs
->event_thread
->suspend
.stop_signal
);
4477 /* If not, perhaps stepping/nexting can. */
4479 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4480 && currently_stepping (ecs
->event_thread
));
4482 /* Perhaps the thread hit a single-step breakpoint of _another_
4483 thread. Single-step breakpoints are transparent to the
4484 breakpoints module. */
4486 random_signal
= !ecs
->hit_singlestep_breakpoint
;
4488 /* No? Perhaps we got a moribund watchpoint. */
4490 random_signal
= !stopped_by_watchpoint
;
4492 /* For the program's own signals, act according to
4493 the signal handling tables. */
4497 /* Signal not for debugging purposes. */
4498 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4499 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
4502 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
4503 gdb_signal_to_symbol_string (stop_signal
));
4505 stopped_by_random_signal
= 1;
4507 /* Always stop on signals if we're either just gaining control
4508 of the program, or the user explicitly requested this thread
4509 to remain stopped. */
4510 if (stop_soon
!= NO_STOP_QUIETLY
4511 || ecs
->event_thread
->stop_requested
4513 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4519 /* Notify observers the signal has "handle print" set. Note we
4520 returned early above if stopping; normal_stop handles the
4521 printing in that case. */
4522 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4524 /* The signal table tells us to print about this signal. */
4525 target_terminal_ours_for_output ();
4526 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
4527 target_terminal_inferior ();
4530 /* Clear the signal if it should not be passed. */
4531 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4532 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4534 if (ecs
->event_thread
->prev_pc
== stop_pc
4535 && ecs
->event_thread
->control
.trap_expected
4536 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4538 /* We were just starting a new sequence, attempting to
4539 single-step off of a breakpoint and expecting a SIGTRAP.
4540 Instead this signal arrives. This signal will take us out
4541 of the stepping range so GDB needs to remember to, when
4542 the signal handler returns, resume stepping off that
4544 /* To simplify things, "continue" is forced to use the same
4545 code paths as single-step - set a breakpoint at the
4546 signal return address and then, once hit, step off that
4549 fprintf_unfiltered (gdb_stdlog
,
4550 "infrun: signal arrived while stepping over "
4553 insert_hp_step_resume_breakpoint_at_frame (frame
);
4554 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4555 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4556 ecs
->event_thread
->control
.trap_expected
= 0;
4558 /* If we were nexting/stepping some other thread, switch to
4559 it, so that we don't continue it, losing control. */
4560 if (!switch_back_to_stepped_thread (ecs
))
4565 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4566 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4567 || ecs
->event_thread
->control
.step_range_end
== 1)
4568 && frame_id_eq (get_stack_frame_id (frame
),
4569 ecs
->event_thread
->control
.step_stack_frame_id
)
4570 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4572 /* The inferior is about to take a signal that will take it
4573 out of the single step range. Set a breakpoint at the
4574 current PC (which is presumably where the signal handler
4575 will eventually return) and then allow the inferior to
4578 Note that this is only needed for a signal delivered
4579 while in the single-step range. Nested signals aren't a
4580 problem as they eventually all return. */
4582 fprintf_unfiltered (gdb_stdlog
,
4583 "infrun: signal may take us out of "
4584 "single-step range\n");
4586 insert_hp_step_resume_breakpoint_at_frame (frame
);
4587 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4588 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4589 ecs
->event_thread
->control
.trap_expected
= 0;
4594 /* Note: step_resume_breakpoint may be non-NULL. This occures
4595 when either there's a nested signal, or when there's a
4596 pending signal enabled just as the signal handler returns
4597 (leaving the inferior at the step-resume-breakpoint without
4598 actually executing it). Either way continue until the
4599 breakpoint is really hit. */
4601 if (!switch_back_to_stepped_thread (ecs
))
4604 fprintf_unfiltered (gdb_stdlog
,
4605 "infrun: random signal, keep going\n");
4612 process_event_stop_test (ecs
);
4615 /* Come here when we've got some debug event / signal we can explain
4616 (IOW, not a random signal), and test whether it should cause a
4617 stop, or whether we should resume the inferior (transparently).
4618 E.g., could be a breakpoint whose condition evaluates false; we
4619 could be still stepping within the line; etc. */
4622 process_event_stop_test (struct execution_control_state
*ecs
)
4624 struct symtab_and_line stop_pc_sal
;
4625 struct frame_info
*frame
;
4626 struct gdbarch
*gdbarch
;
4627 CORE_ADDR jmp_buf_pc
;
4628 struct bpstat_what what
;
4630 /* Handle cases caused by hitting a breakpoint. */
4632 frame
= get_current_frame ();
4633 gdbarch
= get_frame_arch (frame
);
4635 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4637 if (what
.call_dummy
)
4639 stop_stack_dummy
= what
.call_dummy
;
4642 /* If we hit an internal event that triggers symbol changes, the
4643 current frame will be invalidated within bpstat_what (e.g., if we
4644 hit an internal solib event). Re-fetch it. */
4645 frame
= get_current_frame ();
4646 gdbarch
= get_frame_arch (frame
);
4648 switch (what
.main_action
)
4650 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4651 /* If we hit the breakpoint at longjmp while stepping, we
4652 install a momentary breakpoint at the target of the
4656 fprintf_unfiltered (gdb_stdlog
,
4657 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4659 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4661 if (what
.is_longjmp
)
4663 struct value
*arg_value
;
4665 /* If we set the longjmp breakpoint via a SystemTap probe,
4666 then use it to extract the arguments. The destination PC
4667 is the third argument to the probe. */
4668 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4671 jmp_buf_pc
= value_as_address (arg_value
);
4672 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
4674 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4675 || !gdbarch_get_longjmp_target (gdbarch
,
4676 frame
, &jmp_buf_pc
))
4679 fprintf_unfiltered (gdb_stdlog
,
4680 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4681 "(!gdbarch_get_longjmp_target)\n");
4686 /* Insert a breakpoint at resume address. */
4687 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4690 check_exception_resume (ecs
, frame
);
4694 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4696 struct frame_info
*init_frame
;
4698 /* There are several cases to consider.
4700 1. The initiating frame no longer exists. In this case we
4701 must stop, because the exception or longjmp has gone too
4704 2. The initiating frame exists, and is the same as the
4705 current frame. We stop, because the exception or longjmp
4708 3. The initiating frame exists and is different from the
4709 current frame. This means the exception or longjmp has
4710 been caught beneath the initiating frame, so keep going.
4712 4. longjmp breakpoint has been placed just to protect
4713 against stale dummy frames and user is not interested in
4714 stopping around longjmps. */
4717 fprintf_unfiltered (gdb_stdlog
,
4718 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4720 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4722 delete_exception_resume_breakpoint (ecs
->event_thread
);
4724 if (what
.is_longjmp
)
4726 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
4728 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4736 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4740 struct frame_id current_id
4741 = get_frame_id (get_current_frame ());
4742 if (frame_id_eq (current_id
,
4743 ecs
->event_thread
->initiating_frame
))
4745 /* Case 2. Fall through. */
4755 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
4757 delete_step_resume_breakpoint (ecs
->event_thread
);
4759 end_stepping_range (ecs
);
4763 case BPSTAT_WHAT_SINGLE
:
4765 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4766 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4767 /* Still need to check other stuff, at least the case where we
4768 are stepping and step out of the right range. */
4771 case BPSTAT_WHAT_STEP_RESUME
:
4773 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4775 delete_step_resume_breakpoint (ecs
->event_thread
);
4776 if (ecs
->event_thread
->control
.proceed_to_finish
4777 && execution_direction
== EXEC_REVERSE
)
4779 struct thread_info
*tp
= ecs
->event_thread
;
4781 /* We are finishing a function in reverse, and just hit the
4782 step-resume breakpoint at the start address of the
4783 function, and we're almost there -- just need to back up
4784 by one more single-step, which should take us back to the
4786 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4790 fill_in_stop_func (gdbarch
, ecs
);
4791 if (stop_pc
== ecs
->stop_func_start
4792 && execution_direction
== EXEC_REVERSE
)
4794 /* We are stepping over a function call in reverse, and just
4795 hit the step-resume breakpoint at the start address of
4796 the function. Go back to single-stepping, which should
4797 take us back to the function call. */
4798 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4804 case BPSTAT_WHAT_STOP_NOISY
:
4806 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4807 stop_print_frame
= 1;
4809 /* Assume the thread stopped for a breapoint. We'll still check
4810 whether a/the breakpoint is there when the thread is next
4812 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4817 case BPSTAT_WHAT_STOP_SILENT
:
4819 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4820 stop_print_frame
= 0;
4822 /* Assume the thread stopped for a breapoint. We'll still check
4823 whether a/the breakpoint is there when the thread is next
4825 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4829 case BPSTAT_WHAT_HP_STEP_RESUME
:
4831 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4833 delete_step_resume_breakpoint (ecs
->event_thread
);
4834 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4836 /* Back when the step-resume breakpoint was inserted, we
4837 were trying to single-step off a breakpoint. Go back to
4839 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4840 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4846 case BPSTAT_WHAT_KEEP_CHECKING
:
4850 /* If we stepped a permanent breakpoint and we had a high priority
4851 step-resume breakpoint for the address we stepped, but we didn't
4852 hit it, then we must have stepped into the signal handler. The
4853 step-resume was only necessary to catch the case of _not_
4854 stepping into the handler, so delete it, and fall through to
4855 checking whether the step finished. */
4856 if (ecs
->event_thread
->stepped_breakpoint
)
4858 struct breakpoint
*sr_bp
4859 = ecs
->event_thread
->control
.step_resume_breakpoint
;
4861 if (sr_bp
->loc
->permanent
4862 && sr_bp
->type
== bp_hp_step_resume
4863 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
4866 fprintf_unfiltered (gdb_stdlog
,
4867 "infrun: stepped permanent breakpoint, stopped in "
4869 delete_step_resume_breakpoint (ecs
->event_thread
);
4870 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4874 /* We come here if we hit a breakpoint but should not stop for it.
4875 Possibly we also were stepping and should stop for that. So fall
4876 through and test for stepping. But, if not stepping, do not
4879 /* In all-stop mode, if we're currently stepping but have stopped in
4880 some other thread, we need to switch back to the stepped thread. */
4881 if (switch_back_to_stepped_thread (ecs
))
4884 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4887 fprintf_unfiltered (gdb_stdlog
,
4888 "infrun: step-resume breakpoint is inserted\n");
4890 /* Having a step-resume breakpoint overrides anything
4891 else having to do with stepping commands until
4892 that breakpoint is reached. */
4897 if (ecs
->event_thread
->control
.step_range_end
== 0)
4900 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4901 /* Likewise if we aren't even stepping. */
4906 /* Re-fetch current thread's frame in case the code above caused
4907 the frame cache to be re-initialized, making our FRAME variable
4908 a dangling pointer. */
4909 frame
= get_current_frame ();
4910 gdbarch
= get_frame_arch (frame
);
4911 fill_in_stop_func (gdbarch
, ecs
);
4913 /* If stepping through a line, keep going if still within it.
4915 Note that step_range_end is the address of the first instruction
4916 beyond the step range, and NOT the address of the last instruction
4919 Note also that during reverse execution, we may be stepping
4920 through a function epilogue and therefore must detect when
4921 the current-frame changes in the middle of a line. */
4923 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4924 && (execution_direction
!= EXEC_REVERSE
4925 || frame_id_eq (get_frame_id (frame
),
4926 ecs
->event_thread
->control
.step_frame_id
)))
4930 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4931 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4932 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4934 /* Tentatively re-enable range stepping; `resume' disables it if
4935 necessary (e.g., if we're stepping over a breakpoint or we
4936 have software watchpoints). */
4937 ecs
->event_thread
->control
.may_range_step
= 1;
4939 /* When stepping backward, stop at beginning of line range
4940 (unless it's the function entry point, in which case
4941 keep going back to the call point). */
4942 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4943 && stop_pc
!= ecs
->stop_func_start
4944 && execution_direction
== EXEC_REVERSE
)
4945 end_stepping_range (ecs
);
4952 /* We stepped out of the stepping range. */
4954 /* If we are stepping at the source level and entered the runtime
4955 loader dynamic symbol resolution code...
4957 EXEC_FORWARD: we keep on single stepping until we exit the run
4958 time loader code and reach the callee's address.
4960 EXEC_REVERSE: we've already executed the callee (backward), and
4961 the runtime loader code is handled just like any other
4962 undebuggable function call. Now we need only keep stepping
4963 backward through the trampoline code, and that's handled further
4964 down, so there is nothing for us to do here. */
4966 if (execution_direction
!= EXEC_REVERSE
4967 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4968 && in_solib_dynsym_resolve_code (stop_pc
))
4970 CORE_ADDR pc_after_resolver
=
4971 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4974 fprintf_unfiltered (gdb_stdlog
,
4975 "infrun: stepped into dynsym resolve code\n");
4977 if (pc_after_resolver
)
4979 /* Set up a step-resume breakpoint at the address
4980 indicated by SKIP_SOLIB_RESOLVER. */
4981 struct symtab_and_line sr_sal
;
4984 sr_sal
.pc
= pc_after_resolver
;
4985 sr_sal
.pspace
= get_frame_program_space (frame
);
4987 insert_step_resume_breakpoint_at_sal (gdbarch
,
4988 sr_sal
, null_frame_id
);
4995 if (ecs
->event_thread
->control
.step_range_end
!= 1
4996 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4997 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4998 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
5001 fprintf_unfiltered (gdb_stdlog
,
5002 "infrun: stepped into signal trampoline\n");
5003 /* The inferior, while doing a "step" or "next", has ended up in
5004 a signal trampoline (either by a signal being delivered or by
5005 the signal handler returning). Just single-step until the
5006 inferior leaves the trampoline (either by calling the handler
5012 /* If we're in the return path from a shared library trampoline,
5013 we want to proceed through the trampoline when stepping. */
5014 /* macro/2012-04-25: This needs to come before the subroutine
5015 call check below as on some targets return trampolines look
5016 like subroutine calls (MIPS16 return thunks). */
5017 if (gdbarch_in_solib_return_trampoline (gdbarch
,
5018 stop_pc
, ecs
->stop_func_name
)
5019 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5021 /* Determine where this trampoline returns. */
5022 CORE_ADDR real_stop_pc
;
5024 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5027 fprintf_unfiltered (gdb_stdlog
,
5028 "infrun: stepped into solib return tramp\n");
5030 /* Only proceed through if we know where it's going. */
5033 /* And put the step-breakpoint there and go until there. */
5034 struct symtab_and_line sr_sal
;
5036 init_sal (&sr_sal
); /* initialize to zeroes */
5037 sr_sal
.pc
= real_stop_pc
;
5038 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5039 sr_sal
.pspace
= get_frame_program_space (frame
);
5041 /* Do not specify what the fp should be when we stop since
5042 on some machines the prologue is where the new fp value
5044 insert_step_resume_breakpoint_at_sal (gdbarch
,
5045 sr_sal
, null_frame_id
);
5047 /* Restart without fiddling with the step ranges or
5054 /* Check for subroutine calls. The check for the current frame
5055 equalling the step ID is not necessary - the check of the
5056 previous frame's ID is sufficient - but it is a common case and
5057 cheaper than checking the previous frame's ID.
5059 NOTE: frame_id_eq will never report two invalid frame IDs as
5060 being equal, so to get into this block, both the current and
5061 previous frame must have valid frame IDs. */
5062 /* The outer_frame_id check is a heuristic to detect stepping
5063 through startup code. If we step over an instruction which
5064 sets the stack pointer from an invalid value to a valid value,
5065 we may detect that as a subroutine call from the mythical
5066 "outermost" function. This could be fixed by marking
5067 outermost frames as !stack_p,code_p,special_p. Then the
5068 initial outermost frame, before sp was valid, would
5069 have code_addr == &_start. See the comment in frame_id_eq
5071 if (!frame_id_eq (get_stack_frame_id (frame
),
5072 ecs
->event_thread
->control
.step_stack_frame_id
)
5073 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
5074 ecs
->event_thread
->control
.step_stack_frame_id
)
5075 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
5077 || step_start_function
!= find_pc_function (stop_pc
))))
5079 CORE_ADDR real_stop_pc
;
5082 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
5084 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
5086 /* I presume that step_over_calls is only 0 when we're
5087 supposed to be stepping at the assembly language level
5088 ("stepi"). Just stop. */
5089 /* And this works the same backward as frontward. MVS */
5090 end_stepping_range (ecs
);
5094 /* Reverse stepping through solib trampolines. */
5096 if (execution_direction
== EXEC_REVERSE
5097 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
5098 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5099 || (ecs
->stop_func_start
== 0
5100 && in_solib_dynsym_resolve_code (stop_pc
))))
5102 /* Any solib trampoline code can be handled in reverse
5103 by simply continuing to single-step. We have already
5104 executed the solib function (backwards), and a few
5105 steps will take us back through the trampoline to the
5111 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5113 /* We're doing a "next".
5115 Normal (forward) execution: set a breakpoint at the
5116 callee's return address (the address at which the caller
5119 Reverse (backward) execution. set the step-resume
5120 breakpoint at the start of the function that we just
5121 stepped into (backwards), and continue to there. When we
5122 get there, we'll need to single-step back to the caller. */
5124 if (execution_direction
== EXEC_REVERSE
)
5126 /* If we're already at the start of the function, we've either
5127 just stepped backward into a single instruction function,
5128 or stepped back out of a signal handler to the first instruction
5129 of the function. Just keep going, which will single-step back
5131 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
5133 struct symtab_and_line sr_sal
;
5135 /* Normal function call return (static or dynamic). */
5137 sr_sal
.pc
= ecs
->stop_func_start
;
5138 sr_sal
.pspace
= get_frame_program_space (frame
);
5139 insert_step_resume_breakpoint_at_sal (gdbarch
,
5140 sr_sal
, null_frame_id
);
5144 insert_step_resume_breakpoint_at_caller (frame
);
5150 /* If we are in a function call trampoline (a stub between the
5151 calling routine and the real function), locate the real
5152 function. That's what tells us (a) whether we want to step
5153 into it at all, and (b) what prologue we want to run to the
5154 end of, if we do step into it. */
5155 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
5156 if (real_stop_pc
== 0)
5157 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5158 if (real_stop_pc
!= 0)
5159 ecs
->stop_func_start
= real_stop_pc
;
5161 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
5163 struct symtab_and_line sr_sal
;
5166 sr_sal
.pc
= ecs
->stop_func_start
;
5167 sr_sal
.pspace
= get_frame_program_space (frame
);
5169 insert_step_resume_breakpoint_at_sal (gdbarch
,
5170 sr_sal
, null_frame_id
);
5175 /* If we have line number information for the function we are
5176 thinking of stepping into and the function isn't on the skip
5179 If there are several symtabs at that PC (e.g. with include
5180 files), just want to know whether *any* of them have line
5181 numbers. find_pc_line handles this. */
5183 struct symtab_and_line tmp_sal
;
5185 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5186 if (tmp_sal
.line
!= 0
5187 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
5190 if (execution_direction
== EXEC_REVERSE
)
5191 handle_step_into_function_backward (gdbarch
, ecs
);
5193 handle_step_into_function (gdbarch
, ecs
);
5198 /* If we have no line number and the step-stop-if-no-debug is
5199 set, we stop the step so that the user has a chance to switch
5200 in assembly mode. */
5201 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5202 && step_stop_if_no_debug
)
5204 end_stepping_range (ecs
);
5208 if (execution_direction
== EXEC_REVERSE
)
5210 /* If we're already at the start of the function, we've either just
5211 stepped backward into a single instruction function without line
5212 number info, or stepped back out of a signal handler to the first
5213 instruction of the function without line number info. Just keep
5214 going, which will single-step back to the caller. */
5215 if (ecs
->stop_func_start
!= stop_pc
)
5217 /* Set a breakpoint at callee's start address.
5218 From there we can step once and be back in the caller. */
5219 struct symtab_and_line sr_sal
;
5222 sr_sal
.pc
= ecs
->stop_func_start
;
5223 sr_sal
.pspace
= get_frame_program_space (frame
);
5224 insert_step_resume_breakpoint_at_sal (gdbarch
,
5225 sr_sal
, null_frame_id
);
5229 /* Set a breakpoint at callee's return address (the address
5230 at which the caller will resume). */
5231 insert_step_resume_breakpoint_at_caller (frame
);
5237 /* Reverse stepping through solib trampolines. */
5239 if (execution_direction
== EXEC_REVERSE
5240 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5242 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5243 || (ecs
->stop_func_start
== 0
5244 && in_solib_dynsym_resolve_code (stop_pc
)))
5246 /* Any solib trampoline code can be handled in reverse
5247 by simply continuing to single-step. We have already
5248 executed the solib function (backwards), and a few
5249 steps will take us back through the trampoline to the
5254 else if (in_solib_dynsym_resolve_code (stop_pc
))
5256 /* Stepped backward into the solib dynsym resolver.
5257 Set a breakpoint at its start and continue, then
5258 one more step will take us out. */
5259 struct symtab_and_line sr_sal
;
5262 sr_sal
.pc
= ecs
->stop_func_start
;
5263 sr_sal
.pspace
= get_frame_program_space (frame
);
5264 insert_step_resume_breakpoint_at_sal (gdbarch
,
5265 sr_sal
, null_frame_id
);
5271 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5273 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5274 the trampoline processing logic, however, there are some trampolines
5275 that have no names, so we should do trampoline handling first. */
5276 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5277 && ecs
->stop_func_name
== NULL
5278 && stop_pc_sal
.line
== 0)
5281 fprintf_unfiltered (gdb_stdlog
,
5282 "infrun: stepped into undebuggable function\n");
5284 /* The inferior just stepped into, or returned to, an
5285 undebuggable function (where there is no debugging information
5286 and no line number corresponding to the address where the
5287 inferior stopped). Since we want to skip this kind of code,
5288 we keep going until the inferior returns from this
5289 function - unless the user has asked us not to (via
5290 set step-mode) or we no longer know how to get back
5291 to the call site. */
5292 if (step_stop_if_no_debug
5293 || !frame_id_p (frame_unwind_caller_id (frame
)))
5295 /* If we have no line number and the step-stop-if-no-debug
5296 is set, we stop the step so that the user has a chance to
5297 switch in assembly mode. */
5298 end_stepping_range (ecs
);
5303 /* Set a breakpoint at callee's return address (the address
5304 at which the caller will resume). */
5305 insert_step_resume_breakpoint_at_caller (frame
);
5311 if (ecs
->event_thread
->control
.step_range_end
== 1)
5313 /* It is stepi or nexti. We always want to stop stepping after
5316 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5317 end_stepping_range (ecs
);
5321 if (stop_pc_sal
.line
== 0)
5323 /* We have no line number information. That means to stop
5324 stepping (does this always happen right after one instruction,
5325 when we do "s" in a function with no line numbers,
5326 or can this happen as a result of a return or longjmp?). */
5328 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5329 end_stepping_range (ecs
);
5333 /* Look for "calls" to inlined functions, part one. If the inline
5334 frame machinery detected some skipped call sites, we have entered
5335 a new inline function. */
5337 if (frame_id_eq (get_frame_id (get_current_frame ()),
5338 ecs
->event_thread
->control
.step_frame_id
)
5339 && inline_skipped_frames (ecs
->ptid
))
5341 struct symtab_and_line call_sal
;
5344 fprintf_unfiltered (gdb_stdlog
,
5345 "infrun: stepped into inlined function\n");
5347 find_frame_sal (get_current_frame (), &call_sal
);
5349 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5351 /* For "step", we're going to stop. But if the call site
5352 for this inlined function is on the same source line as
5353 we were previously stepping, go down into the function
5354 first. Otherwise stop at the call site. */
5356 if (call_sal
.line
== ecs
->event_thread
->current_line
5357 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5358 step_into_inline_frame (ecs
->ptid
);
5360 end_stepping_range (ecs
);
5365 /* For "next", we should stop at the call site if it is on a
5366 different source line. Otherwise continue through the
5367 inlined function. */
5368 if (call_sal
.line
== ecs
->event_thread
->current_line
5369 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5372 end_stepping_range (ecs
);
5377 /* Look for "calls" to inlined functions, part two. If we are still
5378 in the same real function we were stepping through, but we have
5379 to go further up to find the exact frame ID, we are stepping
5380 through a more inlined call beyond its call site. */
5382 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5383 && !frame_id_eq (get_frame_id (get_current_frame ()),
5384 ecs
->event_thread
->control
.step_frame_id
)
5385 && stepped_in_from (get_current_frame (),
5386 ecs
->event_thread
->control
.step_frame_id
))
5389 fprintf_unfiltered (gdb_stdlog
,
5390 "infrun: stepping through inlined function\n");
5392 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5395 end_stepping_range (ecs
);
5399 if ((stop_pc
== stop_pc_sal
.pc
)
5400 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5401 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5403 /* We are at the start of a different line. So stop. Note that
5404 we don't stop if we step into the middle of a different line.
5405 That is said to make things like for (;;) statements work
5408 fprintf_unfiltered (gdb_stdlog
,
5409 "infrun: stepped to a different line\n");
5410 end_stepping_range (ecs
);
5414 /* We aren't done stepping.
5416 Optimize by setting the stepping range to the line.
5417 (We might not be in the original line, but if we entered a
5418 new line in mid-statement, we continue stepping. This makes
5419 things like for(;;) statements work better.) */
5421 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5422 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5423 ecs
->event_thread
->control
.may_range_step
= 1;
5424 set_step_info (frame
, stop_pc_sal
);
5427 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5431 /* In all-stop mode, if we're currently stepping but have stopped in
5432 some other thread, we may need to switch back to the stepped
5433 thread. Returns true we set the inferior running, false if we left
5434 it stopped (and the event needs further processing). */
5437 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
5441 struct thread_info
*tp
;
5442 struct thread_info
*stepping_thread
;
5443 struct thread_info
*step_over
;
5445 /* If any thread is blocked on some internal breakpoint, and we
5446 simply need to step over that breakpoint to get it going
5447 again, do that first. */
5449 /* However, if we see an event for the stepping thread, then we
5450 know all other threads have been moved past their breakpoints
5451 already. Let the caller check whether the step is finished,
5452 etc., before deciding to move it past a breakpoint. */
5453 if (ecs
->event_thread
->control
.step_range_end
!= 0)
5456 /* Check if the current thread is blocked on an incomplete
5457 step-over, interrupted by a random signal. */
5458 if (ecs
->event_thread
->control
.trap_expected
5459 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5463 fprintf_unfiltered (gdb_stdlog
,
5464 "infrun: need to finish step-over of [%s]\n",
5465 target_pid_to_str (ecs
->event_thread
->ptid
));
5471 /* Check if the current thread is blocked by a single-step
5472 breakpoint of another thread. */
5473 if (ecs
->hit_singlestep_breakpoint
)
5477 fprintf_unfiltered (gdb_stdlog
,
5478 "infrun: need to step [%s] over single-step "
5480 target_pid_to_str (ecs
->ptid
));
5486 /* Otherwise, we no longer expect a trap in the current thread.
5487 Clear the trap_expected flag before switching back -- this is
5488 what keep_going does as well, if we call it. */
5489 ecs
->event_thread
->control
.trap_expected
= 0;
5491 /* Likewise, clear the signal if it should not be passed. */
5492 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5493 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5495 /* If scheduler locking applies even if not stepping, there's no
5496 need to walk over threads. Above we've checked whether the
5497 current thread is stepping. If some other thread not the
5498 event thread is stepping, then it must be that scheduler
5499 locking is not in effect. */
5500 if (schedlock_applies (0))
5503 /* Look for the stepping/nexting thread, and check if any other
5504 thread other than the stepping thread needs to start a
5505 step-over. Do all step-overs before actually proceeding with
5507 stepping_thread
= NULL
;
5509 ALL_NON_EXITED_THREADS (tp
)
5511 /* Ignore threads of processes we're not resuming. */
5513 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
5516 /* When stepping over a breakpoint, we lock all threads
5517 except the one that needs to move past the breakpoint.
5518 If a non-event thread has this set, the "incomplete
5519 step-over" check above should have caught it earlier. */
5520 gdb_assert (!tp
->control
.trap_expected
);
5522 /* Did we find the stepping thread? */
5523 if (tp
->control
.step_range_end
)
5525 /* Yep. There should only one though. */
5526 gdb_assert (stepping_thread
== NULL
);
5528 /* The event thread is handled at the top, before we
5530 gdb_assert (tp
!= ecs
->event_thread
);
5532 /* If some thread other than the event thread is
5533 stepping, then scheduler locking can't be in effect,
5534 otherwise we wouldn't have resumed the current event
5535 thread in the first place. */
5536 gdb_assert (!schedlock_applies (currently_stepping (tp
)));
5538 stepping_thread
= tp
;
5540 else if (thread_still_needs_step_over (tp
))
5544 /* At the top we've returned early if the event thread
5545 is stepping. If some other thread not the event
5546 thread is stepping, then scheduler locking can't be
5547 in effect, and we can resume this thread. No need to
5548 keep looking for the stepping thread then. */
5553 if (step_over
!= NULL
)
5558 fprintf_unfiltered (gdb_stdlog
,
5559 "infrun: need to step-over [%s]\n",
5560 target_pid_to_str (tp
->ptid
));
5563 /* Only the stepping thread should have this set. */
5564 gdb_assert (tp
->control
.step_range_end
== 0);
5566 ecs
->ptid
= tp
->ptid
;
5567 ecs
->event_thread
= tp
;
5568 switch_to_thread (ecs
->ptid
);
5573 if (stepping_thread
!= NULL
)
5575 struct frame_info
*frame
;
5576 struct gdbarch
*gdbarch
;
5578 tp
= stepping_thread
;
5580 /* If the stepping thread exited, then don't try to switch
5581 back and resume it, which could fail in several different
5582 ways depending on the target. Instead, just keep going.
5584 We can find a stepping dead thread in the thread list in
5587 - The target supports thread exit events, and when the
5588 target tries to delete the thread from the thread list,
5589 inferior_ptid pointed at the exiting thread. In such
5590 case, calling delete_thread does not really remove the
5591 thread from the list; instead, the thread is left listed,
5592 with 'exited' state.
5594 - The target's debug interface does not support thread
5595 exit events, and so we have no idea whatsoever if the
5596 previously stepping thread is still alive. For that
5597 reason, we need to synchronously query the target
5599 if (is_exited (tp
->ptid
)
5600 || !target_thread_alive (tp
->ptid
))
5603 fprintf_unfiltered (gdb_stdlog
,
5604 "infrun: not switching back to "
5605 "stepped thread, it has vanished\n");
5607 delete_thread (tp
->ptid
);
5613 fprintf_unfiltered (gdb_stdlog
,
5614 "infrun: switching back to stepped thread\n");
5616 ecs
->event_thread
= tp
;
5617 ecs
->ptid
= tp
->ptid
;
5618 context_switch (ecs
->ptid
);
5620 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5621 frame
= get_current_frame ();
5622 gdbarch
= get_frame_arch (frame
);
5624 /* If the PC of the thread we were trying to single-step has
5625 changed, then that thread has trapped or been signaled,
5626 but the event has not been reported to GDB yet. Re-poll
5627 the target looking for this particular thread's event
5628 (i.e. temporarily enable schedlock) by:
5630 - setting a break at the current PC
5631 - resuming that particular thread, only (by setting
5634 This prevents us continuously moving the single-step
5635 breakpoint forward, one instruction at a time,
5638 if (stop_pc
!= tp
->prev_pc
)
5641 fprintf_unfiltered (gdb_stdlog
,
5642 "infrun: expected thread advanced also\n");
5644 /* Clear the info of the previous step-over, as it's no
5645 longer valid. It's what keep_going would do too, if
5646 we called it. Must do this before trying to insert
5647 the sss breakpoint, otherwise if we were previously
5648 trying to step over this exact address in another
5649 thread, the breakpoint ends up not installed. */
5650 clear_step_over_info ();
5652 insert_single_step_breakpoint (get_frame_arch (frame
),
5653 get_frame_address_space (frame
),
5655 ecs
->event_thread
->control
.trap_expected
= 1;
5657 resume (0, GDB_SIGNAL_0
);
5658 prepare_to_wait (ecs
);
5663 fprintf_unfiltered (gdb_stdlog
,
5664 "infrun: expected thread still "
5665 "hasn't advanced\n");
5675 /* Is thread TP in the middle of single-stepping? */
5678 currently_stepping (struct thread_info
*tp
)
5680 return ((tp
->control
.step_range_end
5681 && tp
->control
.step_resume_breakpoint
== NULL
)
5682 || tp
->control
.trap_expected
5683 || tp
->stepped_breakpoint
5684 || bpstat_should_step ());
5687 /* Inferior has stepped into a subroutine call with source code that
5688 we should not step over. Do step to the first line of code in
5692 handle_step_into_function (struct gdbarch
*gdbarch
,
5693 struct execution_control_state
*ecs
)
5695 struct compunit_symtab
*cust
;
5696 struct symtab_and_line stop_func_sal
, sr_sal
;
5698 fill_in_stop_func (gdbarch
, ecs
);
5700 cust
= find_pc_compunit_symtab (stop_pc
);
5701 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
5702 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5703 ecs
->stop_func_start
);
5705 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5706 /* Use the step_resume_break to step until the end of the prologue,
5707 even if that involves jumps (as it seems to on the vax under
5709 /* If the prologue ends in the middle of a source line, continue to
5710 the end of that source line (if it is still within the function).
5711 Otherwise, just go to end of prologue. */
5712 if (stop_func_sal
.end
5713 && stop_func_sal
.pc
!= ecs
->stop_func_start
5714 && stop_func_sal
.end
< ecs
->stop_func_end
)
5715 ecs
->stop_func_start
= stop_func_sal
.end
;
5717 /* Architectures which require breakpoint adjustment might not be able
5718 to place a breakpoint at the computed address. If so, the test
5719 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5720 ecs->stop_func_start to an address at which a breakpoint may be
5721 legitimately placed.
5723 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5724 made, GDB will enter an infinite loop when stepping through
5725 optimized code consisting of VLIW instructions which contain
5726 subinstructions corresponding to different source lines. On
5727 FR-V, it's not permitted to place a breakpoint on any but the
5728 first subinstruction of a VLIW instruction. When a breakpoint is
5729 set, GDB will adjust the breakpoint address to the beginning of
5730 the VLIW instruction. Thus, we need to make the corresponding
5731 adjustment here when computing the stop address. */
5733 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5735 ecs
->stop_func_start
5736 = gdbarch_adjust_breakpoint_address (gdbarch
,
5737 ecs
->stop_func_start
);
5740 if (ecs
->stop_func_start
== stop_pc
)
5742 /* We are already there: stop now. */
5743 end_stepping_range (ecs
);
5748 /* Put the step-breakpoint there and go until there. */
5749 init_sal (&sr_sal
); /* initialize to zeroes */
5750 sr_sal
.pc
= ecs
->stop_func_start
;
5751 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5752 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5754 /* Do not specify what the fp should be when we stop since on
5755 some machines the prologue is where the new fp value is
5757 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5759 /* And make sure stepping stops right away then. */
5760 ecs
->event_thread
->control
.step_range_end
5761 = ecs
->event_thread
->control
.step_range_start
;
5766 /* Inferior has stepped backward into a subroutine call with source
5767 code that we should not step over. Do step to the beginning of the
5768 last line of code in it. */
5771 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5772 struct execution_control_state
*ecs
)
5774 struct compunit_symtab
*cust
;
5775 struct symtab_and_line stop_func_sal
;
5777 fill_in_stop_func (gdbarch
, ecs
);
5779 cust
= find_pc_compunit_symtab (stop_pc
);
5780 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
5781 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5782 ecs
->stop_func_start
);
5784 stop_func_sal
= find_pc_line (stop_pc
, 0);
5786 /* OK, we're just going to keep stepping here. */
5787 if (stop_func_sal
.pc
== stop_pc
)
5789 /* We're there already. Just stop stepping now. */
5790 end_stepping_range (ecs
);
5794 /* Else just reset the step range and keep going.
5795 No step-resume breakpoint, they don't work for
5796 epilogues, which can have multiple entry paths. */
5797 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5798 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5804 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5805 This is used to both functions and to skip over code. */
5808 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5809 struct symtab_and_line sr_sal
,
5810 struct frame_id sr_id
,
5811 enum bptype sr_type
)
5813 /* There should never be more than one step-resume or longjmp-resume
5814 breakpoint per thread, so we should never be setting a new
5815 step_resume_breakpoint when one is already active. */
5816 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5817 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5820 fprintf_unfiltered (gdb_stdlog
,
5821 "infrun: inserting step-resume breakpoint at %s\n",
5822 paddress (gdbarch
, sr_sal
.pc
));
5824 inferior_thread ()->control
.step_resume_breakpoint
5825 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5829 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5830 struct symtab_and_line sr_sal
,
5831 struct frame_id sr_id
)
5833 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5838 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5839 This is used to skip a potential signal handler.
5841 This is called with the interrupted function's frame. The signal
5842 handler, when it returns, will resume the interrupted function at
5846 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5848 struct symtab_and_line sr_sal
;
5849 struct gdbarch
*gdbarch
;
5851 gdb_assert (return_frame
!= NULL
);
5852 init_sal (&sr_sal
); /* initialize to zeros */
5854 gdbarch
= get_frame_arch (return_frame
);
5855 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5856 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5857 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5859 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5860 get_stack_frame_id (return_frame
),
5864 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5865 is used to skip a function after stepping into it (for "next" or if
5866 the called function has no debugging information).
5868 The current function has almost always been reached by single
5869 stepping a call or return instruction. NEXT_FRAME belongs to the
5870 current function, and the breakpoint will be set at the caller's
5873 This is a separate function rather than reusing
5874 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5875 get_prev_frame, which may stop prematurely (see the implementation
5876 of frame_unwind_caller_id for an example). */
5879 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5881 struct symtab_and_line sr_sal
;
5882 struct gdbarch
*gdbarch
;
5884 /* We shouldn't have gotten here if we don't know where the call site
5886 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5888 init_sal (&sr_sal
); /* initialize to zeros */
5890 gdbarch
= frame_unwind_caller_arch (next_frame
);
5891 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5892 frame_unwind_caller_pc (next_frame
));
5893 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5894 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5896 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5897 frame_unwind_caller_id (next_frame
));
5900 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5901 new breakpoint at the target of a jmp_buf. The handling of
5902 longjmp-resume uses the same mechanisms used for handling
5903 "step-resume" breakpoints. */
5906 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5908 /* There should never be more than one longjmp-resume breakpoint per
5909 thread, so we should never be setting a new
5910 longjmp_resume_breakpoint when one is already active. */
5911 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
5914 fprintf_unfiltered (gdb_stdlog
,
5915 "infrun: inserting longjmp-resume breakpoint at %s\n",
5916 paddress (gdbarch
, pc
));
5918 inferior_thread ()->control
.exception_resume_breakpoint
=
5919 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5922 /* Insert an exception resume breakpoint. TP is the thread throwing
5923 the exception. The block B is the block of the unwinder debug hook
5924 function. FRAME is the frame corresponding to the call to this
5925 function. SYM is the symbol of the function argument holding the
5926 target PC of the exception. */
5929 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5930 const struct block
*b
,
5931 struct frame_info
*frame
,
5934 volatile struct gdb_exception e
;
5936 /* We want to ignore errors here. */
5937 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5939 struct symbol
*vsym
;
5940 struct value
*value
;
5942 struct breakpoint
*bp
;
5944 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5945 value
= read_var_value (vsym
, frame
);
5946 /* If the value was optimized out, revert to the old behavior. */
5947 if (! value_optimized_out (value
))
5949 handler
= value_as_address (value
);
5952 fprintf_unfiltered (gdb_stdlog
,
5953 "infrun: exception resume at %lx\n",
5954 (unsigned long) handler
);
5956 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5957 handler
, bp_exception_resume
);
5959 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5962 bp
->thread
= tp
->num
;
5963 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5968 /* A helper for check_exception_resume that sets an
5969 exception-breakpoint based on a SystemTap probe. */
5972 insert_exception_resume_from_probe (struct thread_info
*tp
,
5973 const struct bound_probe
*probe
,
5974 struct frame_info
*frame
)
5976 struct value
*arg_value
;
5978 struct breakpoint
*bp
;
5980 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
5984 handler
= value_as_address (arg_value
);
5987 fprintf_unfiltered (gdb_stdlog
,
5988 "infrun: exception resume at %s\n",
5989 paddress (get_objfile_arch (probe
->objfile
),
5992 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5993 handler
, bp_exception_resume
);
5994 bp
->thread
= tp
->num
;
5995 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5998 /* This is called when an exception has been intercepted. Check to
5999 see whether the exception's destination is of interest, and if so,
6000 set an exception resume breakpoint there. */
6003 check_exception_resume (struct execution_control_state
*ecs
,
6004 struct frame_info
*frame
)
6006 volatile struct gdb_exception e
;
6007 struct bound_probe probe
;
6008 struct symbol
*func
;
6010 /* First see if this exception unwinding breakpoint was set via a
6011 SystemTap probe point. If so, the probe has two arguments: the
6012 CFA and the HANDLER. We ignore the CFA, extract the handler, and
6013 set a breakpoint there. */
6014 probe
= find_probe_by_pc (get_frame_pc (frame
));
6017 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
6021 func
= get_frame_function (frame
);
6025 TRY_CATCH (e
, RETURN_MASK_ERROR
)
6027 const struct block
*b
;
6028 struct block_iterator iter
;
6032 /* The exception breakpoint is a thread-specific breakpoint on
6033 the unwinder's debug hook, declared as:
6035 void _Unwind_DebugHook (void *cfa, void *handler);
6037 The CFA argument indicates the frame to which control is
6038 about to be transferred. HANDLER is the destination PC.
6040 We ignore the CFA and set a temporary breakpoint at HANDLER.
6041 This is not extremely efficient but it avoids issues in gdb
6042 with computing the DWARF CFA, and it also works even in weird
6043 cases such as throwing an exception from inside a signal
6046 b
= SYMBOL_BLOCK_VALUE (func
);
6047 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
6049 if (!SYMBOL_IS_ARGUMENT (sym
))
6056 insert_exception_resume_breakpoint (ecs
->event_thread
,
6065 stop_waiting (struct execution_control_state
*ecs
)
6068 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
6070 clear_step_over_info ();
6072 /* Let callers know we don't want to wait for the inferior anymore. */
6073 ecs
->wait_some_more
= 0;
6076 /* Called when we should continue running the inferior, because the
6077 current event doesn't cause a user visible stop. This does the
6078 resuming part; waiting for the next event is done elsewhere. */
6081 keep_going (struct execution_control_state
*ecs
)
6083 /* Make sure normal_stop is called if we get a QUIT handled before
6085 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
6087 /* Save the pc before execution, to compare with pc after stop. */
6088 ecs
->event_thread
->prev_pc
6089 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
6091 if (ecs
->event_thread
->control
.trap_expected
6092 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6094 /* We haven't yet gotten our trap, and either: intercepted a
6095 non-signal event (e.g., a fork); or took a signal which we
6096 are supposed to pass through to the inferior. Simply
6098 discard_cleanups (old_cleanups
);
6099 resume (currently_stepping (ecs
->event_thread
),
6100 ecs
->event_thread
->suspend
.stop_signal
);
6104 volatile struct gdb_exception e
;
6105 struct regcache
*regcache
= get_current_regcache ();
6109 /* Either the trap was not expected, but we are continuing
6110 anyway (if we got a signal, the user asked it be passed to
6113 We got our expected trap, but decided we should resume from
6116 We're going to run this baby now!
6118 Note that insert_breakpoints won't try to re-insert
6119 already inserted breakpoints. Therefore, we don't
6120 care if breakpoints were already inserted, or not. */
6122 /* If we need to step over a breakpoint, and we're not using
6123 displaced stepping to do so, insert all breakpoints
6124 (watchpoints, etc.) but the one we're stepping over, step one
6125 instruction, and then re-insert the breakpoint when that step
6128 remove_bp
= (ecs
->hit_singlestep_breakpoint
6129 || thread_still_needs_step_over (ecs
->event_thread
));
6130 remove_wps
= (ecs
->event_thread
->stepping_over_watchpoint
6131 && !target_have_steppable_watchpoint
);
6133 if (remove_bp
&& !use_displaced_stepping (get_regcache_arch (regcache
)))
6135 set_step_over_info (get_regcache_aspace (regcache
),
6136 regcache_read_pc (regcache
), remove_wps
);
6138 else if (remove_wps
)
6139 set_step_over_info (NULL
, 0, remove_wps
);
6141 clear_step_over_info ();
6143 /* Stop stepping if inserting breakpoints fails. */
6144 TRY_CATCH (e
, RETURN_MASK_ERROR
)
6146 insert_breakpoints ();
6150 exception_print (gdb_stderr
, e
);
6155 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
6157 /* Do not deliver GDB_SIGNAL_TRAP (except when the user
6158 explicitly specifies that such a signal should be delivered
6159 to the target program). Typically, that would occur when a
6160 user is debugging a target monitor on a simulator: the target
6161 monitor sets a breakpoint; the simulator encounters this
6162 breakpoint and halts the simulation handing control to GDB;
6163 GDB, noting that the stop address doesn't map to any known
6164 breakpoint, returns control back to the simulator; the
6165 simulator then delivers the hardware equivalent of a
6166 GDB_SIGNAL_TRAP to the program being debugged. */
6167 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6168 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6169 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6171 discard_cleanups (old_cleanups
);
6172 resume (currently_stepping (ecs
->event_thread
),
6173 ecs
->event_thread
->suspend
.stop_signal
);
6176 prepare_to_wait (ecs
);
6179 /* This function normally comes after a resume, before
6180 handle_inferior_event exits. It takes care of any last bits of
6181 housekeeping, and sets the all-important wait_some_more flag. */
6184 prepare_to_wait (struct execution_control_state
*ecs
)
6187 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
6189 /* This is the old end of the while loop. Let everybody know we
6190 want to wait for the inferior some more and get called again
6192 ecs
->wait_some_more
= 1;
6195 /* We are done with the step range of a step/next/si/ni command.
6196 Called once for each n of a "step n" operation. */
6199 end_stepping_range (struct execution_control_state
*ecs
)
6201 ecs
->event_thread
->control
.stop_step
= 1;
6205 /* Several print_*_reason functions to print why the inferior has stopped.
6206 We always print something when the inferior exits, or receives a signal.
6207 The rest of the cases are dealt with later on in normal_stop and
6208 print_it_typical. Ideally there should be a call to one of these
6209 print_*_reason functions functions from handle_inferior_event each time
6210 stop_waiting is called.
6212 Note that we don't call these directly, instead we delegate that to
6213 the interpreters, through observers. Interpreters then call these
6214 with whatever uiout is right. */
6217 print_end_stepping_range_reason (struct ui_out
*uiout
)
6219 /* For CLI-like interpreters, print nothing. */
6221 if (ui_out_is_mi_like_p (uiout
))
6223 ui_out_field_string (uiout
, "reason",
6224 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
6229 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6231 annotate_signalled ();
6232 if (ui_out_is_mi_like_p (uiout
))
6234 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
6235 ui_out_text (uiout
, "\nProgram terminated with signal ");
6236 annotate_signal_name ();
6237 ui_out_field_string (uiout
, "signal-name",
6238 gdb_signal_to_name (siggnal
));
6239 annotate_signal_name_end ();
6240 ui_out_text (uiout
, ", ");
6241 annotate_signal_string ();
6242 ui_out_field_string (uiout
, "signal-meaning",
6243 gdb_signal_to_string (siggnal
));
6244 annotate_signal_string_end ();
6245 ui_out_text (uiout
, ".\n");
6246 ui_out_text (uiout
, "The program no longer exists.\n");
6250 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
6252 struct inferior
*inf
= current_inferior ();
6253 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
6255 annotate_exited (exitstatus
);
6258 if (ui_out_is_mi_like_p (uiout
))
6259 ui_out_field_string (uiout
, "reason",
6260 async_reason_lookup (EXEC_ASYNC_EXITED
));
6261 ui_out_text (uiout
, "[Inferior ");
6262 ui_out_text (uiout
, plongest (inf
->num
));
6263 ui_out_text (uiout
, " (");
6264 ui_out_text (uiout
, pidstr
);
6265 ui_out_text (uiout
, ") exited with code ");
6266 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
6267 ui_out_text (uiout
, "]\n");
6271 if (ui_out_is_mi_like_p (uiout
))
6273 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
6274 ui_out_text (uiout
, "[Inferior ");
6275 ui_out_text (uiout
, plongest (inf
->num
));
6276 ui_out_text (uiout
, " (");
6277 ui_out_text (uiout
, pidstr
);
6278 ui_out_text (uiout
, ") exited normally]\n");
6283 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6287 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
6289 struct thread_info
*t
= inferior_thread ();
6291 ui_out_text (uiout
, "\n[");
6292 ui_out_field_string (uiout
, "thread-name",
6293 target_pid_to_str (t
->ptid
));
6294 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
6295 ui_out_text (uiout
, " stopped");
6299 ui_out_text (uiout
, "\nProgram received signal ");
6300 annotate_signal_name ();
6301 if (ui_out_is_mi_like_p (uiout
))
6303 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
6304 ui_out_field_string (uiout
, "signal-name",
6305 gdb_signal_to_name (siggnal
));
6306 annotate_signal_name_end ();
6307 ui_out_text (uiout
, ", ");
6308 annotate_signal_string ();
6309 ui_out_field_string (uiout
, "signal-meaning",
6310 gdb_signal_to_string (siggnal
));
6311 annotate_signal_string_end ();
6313 ui_out_text (uiout
, ".\n");
6317 print_no_history_reason (struct ui_out
*uiout
)
6319 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
6322 /* Print current location without a level number, if we have changed
6323 functions or hit a breakpoint. Print source line if we have one.
6324 bpstat_print contains the logic deciding in detail what to print,
6325 based on the event(s) that just occurred. */
6328 print_stop_event (struct target_waitstatus
*ws
)
6332 int do_frame_printing
= 1;
6333 struct thread_info
*tp
= inferior_thread ();
6335 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
6339 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
6340 should) carry around the function and does (or should) use
6341 that when doing a frame comparison. */
6342 if (tp
->control
.stop_step
6343 && frame_id_eq (tp
->control
.step_frame_id
,
6344 get_frame_id (get_current_frame ()))
6345 && step_start_function
== find_pc_function (stop_pc
))
6347 /* Finished step, just print source line. */
6348 source_flag
= SRC_LINE
;
6352 /* Print location and source line. */
6353 source_flag
= SRC_AND_LOC
;
6356 case PRINT_SRC_AND_LOC
:
6357 /* Print location and source line. */
6358 source_flag
= SRC_AND_LOC
;
6360 case PRINT_SRC_ONLY
:
6361 source_flag
= SRC_LINE
;
6364 /* Something bogus. */
6365 source_flag
= SRC_LINE
;
6366 do_frame_printing
= 0;
6369 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6372 /* The behavior of this routine with respect to the source
6374 SRC_LINE: Print only source line
6375 LOCATION: Print only location
6376 SRC_AND_LOC: Print location and source line. */
6377 if (do_frame_printing
)
6378 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
6380 /* Display the auto-display expressions. */
6384 /* Here to return control to GDB when the inferior stops for real.
6385 Print appropriate messages, remove breakpoints, give terminal our modes.
6387 STOP_PRINT_FRAME nonzero means print the executing frame
6388 (pc, function, args, file, line number and line text).
6389 BREAKPOINTS_FAILED nonzero means stop was due to error
6390 attempting to insert breakpoints. */
6395 struct target_waitstatus last
;
6397 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
6399 get_last_target_status (&last_ptid
, &last
);
6401 /* If an exception is thrown from this point on, make sure to
6402 propagate GDB's knowledge of the executing state to the
6403 frontend/user running state. A QUIT is an easy exception to see
6404 here, so do this before any filtered output. */
6406 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
6407 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6408 && last
.kind
!= TARGET_WAITKIND_EXITED
6409 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6410 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
6412 /* As we're presenting a stop, and potentially removing breakpoints,
6413 update the thread list so we can tell whether there are threads
6414 running on the target. With target remote, for example, we can
6415 only learn about new threads when we explicitly update the thread
6416 list. Do this before notifying the interpreters about signal
6417 stops, end of stepping ranges, etc., so that the "new thread"
6418 output is emitted before e.g., "Program received signal FOO",
6419 instead of after. */
6420 update_thread_list ();
6422 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
6423 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
6425 /* As with the notification of thread events, we want to delay
6426 notifying the user that we've switched thread context until
6427 the inferior actually stops.
6429 There's no point in saying anything if the inferior has exited.
6430 Note that SIGNALLED here means "exited with a signal", not
6431 "received a signal".
6433 Also skip saying anything in non-stop mode. In that mode, as we
6434 don't want GDB to switch threads behind the user's back, to avoid
6435 races where the user is typing a command to apply to thread x,
6436 but GDB switches to thread y before the user finishes entering
6437 the command, fetch_inferior_event installs a cleanup to restore
6438 the current thread back to the thread the user had selected right
6439 after this event is handled, so we're not really switching, only
6440 informing of a stop. */
6442 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
6443 && target_has_execution
6444 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6445 && last
.kind
!= TARGET_WAITKIND_EXITED
6446 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6448 target_terminal_ours_for_output ();
6449 printf_filtered (_("[Switching to %s]\n"),
6450 target_pid_to_str (inferior_ptid
));
6451 annotate_thread_changed ();
6452 previous_inferior_ptid
= inferior_ptid
;
6455 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
6457 gdb_assert (sync_execution
|| !target_can_async_p ());
6459 target_terminal_ours_for_output ();
6460 printf_filtered (_("No unwaited-for children left.\n"));
6463 /* Note: this depends on the update_thread_list call above. */
6464 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
6466 if (remove_breakpoints ())
6468 target_terminal_ours_for_output ();
6469 printf_filtered (_("Cannot remove breakpoints because "
6470 "program is no longer writable.\nFurther "
6471 "execution is probably impossible.\n"));
6475 /* If an auto-display called a function and that got a signal,
6476 delete that auto-display to avoid an infinite recursion. */
6478 if (stopped_by_random_signal
)
6479 disable_current_display ();
6481 /* Notify observers if we finished a "step"-like command, etc. */
6482 if (target_has_execution
6483 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6484 && last
.kind
!= TARGET_WAITKIND_EXITED
6485 && inferior_thread ()->control
.stop_step
)
6487 /* But not if in the middle of doing a "step n" operation for
6489 if (inferior_thread ()->step_multi
)
6492 observer_notify_end_stepping_range ();
6495 target_terminal_ours ();
6496 async_enable_stdin ();
6498 /* Set the current source location. This will also happen if we
6499 display the frame below, but the current SAL will be incorrect
6500 during a user hook-stop function. */
6501 if (has_stack_frames () && !stop_stack_dummy
)
6502 set_current_sal_from_frame (get_current_frame ());
6504 /* Let the user/frontend see the threads as stopped, but do nothing
6505 if the thread was running an infcall. We may be e.g., evaluating
6506 a breakpoint condition. In that case, the thread had state
6507 THREAD_RUNNING before the infcall, and shall remain set to
6508 running, all without informing the user/frontend about state
6509 transition changes. If this is actually a call command, then the
6510 thread was originally already stopped, so there's no state to
6512 if (target_has_execution
&& inferior_thread ()->control
.in_infcall
)
6513 discard_cleanups (old_chain
);
6515 do_cleanups (old_chain
);
6517 /* Look up the hook_stop and run it (CLI internally handles problem
6518 of stop_command's pre-hook not existing). */
6520 catch_errors (hook_stop_stub
, stop_command
,
6521 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6523 if (!has_stack_frames ())
6526 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6527 || last
.kind
== TARGET_WAITKIND_EXITED
)
6530 /* Select innermost stack frame - i.e., current frame is frame 0,
6531 and current location is based on that.
6532 Don't do this on return from a stack dummy routine,
6533 or if the program has exited. */
6535 if (!stop_stack_dummy
)
6537 select_frame (get_current_frame ());
6539 /* If --batch-silent is enabled then there's no need to print the current
6540 source location, and to try risks causing an error message about
6541 missing source files. */
6542 if (stop_print_frame
&& !batch_silent
)
6543 print_stop_event (&last
);
6546 /* Save the function value return registers, if we care.
6547 We might be about to restore their previous contents. */
6548 if (inferior_thread ()->control
.proceed_to_finish
6549 && execution_direction
!= EXEC_REVERSE
)
6551 /* This should not be necessary. */
6553 regcache_xfree (stop_registers
);
6555 /* NB: The copy goes through to the target picking up the value of
6556 all the registers. */
6557 stop_registers
= regcache_dup (get_current_regcache ());
6560 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6562 /* Pop the empty frame that contains the stack dummy.
6563 This also restores inferior state prior to the call
6564 (struct infcall_suspend_state). */
6565 struct frame_info
*frame
= get_current_frame ();
6567 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6569 /* frame_pop() calls reinit_frame_cache as the last thing it
6570 does which means there's currently no selected frame. We
6571 don't need to re-establish a selected frame if the dummy call
6572 returns normally, that will be done by
6573 restore_infcall_control_state. However, we do have to handle
6574 the case where the dummy call is returning after being
6575 stopped (e.g. the dummy call previously hit a breakpoint).
6576 We can't know which case we have so just always re-establish
6577 a selected frame here. */
6578 select_frame (get_current_frame ());
6582 annotate_stopped ();
6584 /* Suppress the stop observer if we're in the middle of:
6586 - a step n (n > 1), as there still more steps to be done.
6588 - a "finish" command, as the observer will be called in
6589 finish_command_continuation, so it can include the inferior
6590 function's return value.
6592 - calling an inferior function, as we pretend we inferior didn't
6593 run at all. The return value of the call is handled by the
6594 expression evaluator, through call_function_by_hand. */
6596 if (!target_has_execution
6597 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6598 || last
.kind
== TARGET_WAITKIND_EXITED
6599 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6600 || (!(inferior_thread ()->step_multi
6601 && inferior_thread ()->control
.stop_step
)
6602 && !(inferior_thread ()->control
.stop_bpstat
6603 && inferior_thread ()->control
.proceed_to_finish
)
6604 && !inferior_thread ()->control
.in_infcall
))
6606 if (!ptid_equal (inferior_ptid
, null_ptid
))
6607 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6610 observer_notify_normal_stop (NULL
, stop_print_frame
);
6613 if (target_has_execution
)
6615 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6616 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6617 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6618 Delete any breakpoint that is to be deleted at the next stop. */
6619 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6622 /* Try to get rid of automatically added inferiors that are no
6623 longer needed. Keeping those around slows down things linearly.
6624 Note that this never removes the current inferior. */
6629 hook_stop_stub (void *cmd
)
6631 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6636 signal_stop_state (int signo
)
6638 return signal_stop
[signo
];
6642 signal_print_state (int signo
)
6644 return signal_print
[signo
];
6648 signal_pass_state (int signo
)
6650 return signal_program
[signo
];
6654 signal_cache_update (int signo
)
6658 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6659 signal_cache_update (signo
);
6664 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6665 && signal_print
[signo
] == 0
6666 && signal_program
[signo
] == 1
6667 && signal_catch
[signo
] == 0);
6671 signal_stop_update (int signo
, int state
)
6673 int ret
= signal_stop
[signo
];
6675 signal_stop
[signo
] = state
;
6676 signal_cache_update (signo
);
6681 signal_print_update (int signo
, int state
)
6683 int ret
= signal_print
[signo
];
6685 signal_print
[signo
] = state
;
6686 signal_cache_update (signo
);
6691 signal_pass_update (int signo
, int state
)
6693 int ret
= signal_program
[signo
];
6695 signal_program
[signo
] = state
;
6696 signal_cache_update (signo
);
6700 /* Update the global 'signal_catch' from INFO and notify the
6704 signal_catch_update (const unsigned int *info
)
6708 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
6709 signal_catch
[i
] = info
[i
] > 0;
6710 signal_cache_update (-1);
6711 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6715 sig_print_header (void)
6717 printf_filtered (_("Signal Stop\tPrint\tPass "
6718 "to program\tDescription\n"));
6722 sig_print_info (enum gdb_signal oursig
)
6724 const char *name
= gdb_signal_to_name (oursig
);
6725 int name_padding
= 13 - strlen (name
);
6727 if (name_padding
<= 0)
6730 printf_filtered ("%s", name
);
6731 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6732 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6733 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6734 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6735 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6738 /* Specify how various signals in the inferior should be handled. */
6741 handle_command (char *args
, int from_tty
)
6744 int digits
, wordlen
;
6745 int sigfirst
, signum
, siglast
;
6746 enum gdb_signal oursig
;
6749 unsigned char *sigs
;
6750 struct cleanup
*old_chain
;
6754 error_no_arg (_("signal to handle"));
6757 /* Allocate and zero an array of flags for which signals to handle. */
6759 nsigs
= (int) GDB_SIGNAL_LAST
;
6760 sigs
= (unsigned char *) alloca (nsigs
);
6761 memset (sigs
, 0, nsigs
);
6763 /* Break the command line up into args. */
6765 argv
= gdb_buildargv (args
);
6766 old_chain
= make_cleanup_freeargv (argv
);
6768 /* Walk through the args, looking for signal oursigs, signal names, and
6769 actions. Signal numbers and signal names may be interspersed with
6770 actions, with the actions being performed for all signals cumulatively
6771 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6773 while (*argv
!= NULL
)
6775 wordlen
= strlen (*argv
);
6776 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6780 sigfirst
= siglast
= -1;
6782 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6784 /* Apply action to all signals except those used by the
6785 debugger. Silently skip those. */
6788 siglast
= nsigs
- 1;
6790 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6792 SET_SIGS (nsigs
, sigs
, signal_stop
);
6793 SET_SIGS (nsigs
, sigs
, signal_print
);
6795 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6797 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6799 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6801 SET_SIGS (nsigs
, sigs
, signal_print
);
6803 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6805 SET_SIGS (nsigs
, sigs
, signal_program
);
6807 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6809 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6811 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6813 SET_SIGS (nsigs
, sigs
, signal_program
);
6815 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6817 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6818 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6820 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6822 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6824 else if (digits
> 0)
6826 /* It is numeric. The numeric signal refers to our own
6827 internal signal numbering from target.h, not to host/target
6828 signal number. This is a feature; users really should be
6829 using symbolic names anyway, and the common ones like
6830 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6832 sigfirst
= siglast
= (int)
6833 gdb_signal_from_command (atoi (*argv
));
6834 if ((*argv
)[digits
] == '-')
6837 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6839 if (sigfirst
> siglast
)
6841 /* Bet he didn't figure we'd think of this case... */
6849 oursig
= gdb_signal_from_name (*argv
);
6850 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6852 sigfirst
= siglast
= (int) oursig
;
6856 /* Not a number and not a recognized flag word => complain. */
6857 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6861 /* If any signal numbers or symbol names were found, set flags for
6862 which signals to apply actions to. */
6864 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6866 switch ((enum gdb_signal
) signum
)
6868 case GDB_SIGNAL_TRAP
:
6869 case GDB_SIGNAL_INT
:
6870 if (!allsigs
&& !sigs
[signum
])
6872 if (query (_("%s is used by the debugger.\n\
6873 Are you sure you want to change it? "),
6874 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6880 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6881 gdb_flush (gdb_stdout
);
6886 case GDB_SIGNAL_DEFAULT
:
6887 case GDB_SIGNAL_UNKNOWN
:
6888 /* Make sure that "all" doesn't print these. */
6899 for (signum
= 0; signum
< nsigs
; signum
++)
6902 signal_cache_update (-1);
6903 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6904 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6908 /* Show the results. */
6909 sig_print_header ();
6910 for (; signum
< nsigs
; signum
++)
6912 sig_print_info (signum
);
6918 do_cleanups (old_chain
);
6921 /* Complete the "handle" command. */
6923 static VEC (char_ptr
) *
6924 handle_completer (struct cmd_list_element
*ignore
,
6925 const char *text
, const char *word
)
6927 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
6928 static const char * const keywords
[] =
6942 vec_signals
= signal_completer (ignore
, text
, word
);
6943 vec_keywords
= complete_on_enum (keywords
, word
, word
);
6945 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
6946 VEC_free (char_ptr
, vec_signals
);
6947 VEC_free (char_ptr
, vec_keywords
);
6952 xdb_handle_command (char *args
, int from_tty
)
6955 struct cleanup
*old_chain
;
6958 error_no_arg (_("xdb command"));
6960 /* Break the command line up into args. */
6962 argv
= gdb_buildargv (args
);
6963 old_chain
= make_cleanup_freeargv (argv
);
6964 if (argv
[1] != (char *) NULL
)
6969 bufLen
= strlen (argv
[0]) + 20;
6970 argBuf
= (char *) xmalloc (bufLen
);
6974 enum gdb_signal oursig
;
6976 oursig
= gdb_signal_from_name (argv
[0]);
6977 memset (argBuf
, 0, bufLen
);
6978 if (strcmp (argv
[1], "Q") == 0)
6979 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6982 if (strcmp (argv
[1], "s") == 0)
6984 if (!signal_stop
[oursig
])
6985 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6987 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6989 else if (strcmp (argv
[1], "i") == 0)
6991 if (!signal_program
[oursig
])
6992 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6994 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6996 else if (strcmp (argv
[1], "r") == 0)
6998 if (!signal_print
[oursig
])
6999 sprintf (argBuf
, "%s %s", argv
[0], "print");
7001 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
7007 handle_command (argBuf
, from_tty
);
7009 printf_filtered (_("Invalid signal handling flag.\n"));
7014 do_cleanups (old_chain
);
7018 gdb_signal_from_command (int num
)
7020 if (num
>= 1 && num
<= 15)
7021 return (enum gdb_signal
) num
;
7022 error (_("Only signals 1-15 are valid as numeric signals.\n\
7023 Use \"info signals\" for a list of symbolic signals."));
7026 /* Print current contents of the tables set by the handle command.
7027 It is possible we should just be printing signals actually used
7028 by the current target (but for things to work right when switching
7029 targets, all signals should be in the signal tables). */
7032 signals_info (char *signum_exp
, int from_tty
)
7034 enum gdb_signal oursig
;
7036 sig_print_header ();
7040 /* First see if this is a symbol name. */
7041 oursig
= gdb_signal_from_name (signum_exp
);
7042 if (oursig
== GDB_SIGNAL_UNKNOWN
)
7044 /* No, try numeric. */
7046 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
7048 sig_print_info (oursig
);
7052 printf_filtered ("\n");
7053 /* These ugly casts brought to you by the native VAX compiler. */
7054 for (oursig
= GDB_SIGNAL_FIRST
;
7055 (int) oursig
< (int) GDB_SIGNAL_LAST
;
7056 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
7060 if (oursig
!= GDB_SIGNAL_UNKNOWN
7061 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
7062 sig_print_info (oursig
);
7065 printf_filtered (_("\nUse the \"handle\" command "
7066 "to change these tables.\n"));
7069 /* Check if it makes sense to read $_siginfo from the current thread
7070 at this point. If not, throw an error. */
7073 validate_siginfo_access (void)
7075 /* No current inferior, no siginfo. */
7076 if (ptid_equal (inferior_ptid
, null_ptid
))
7077 error (_("No thread selected."));
7079 /* Don't try to read from a dead thread. */
7080 if (is_exited (inferior_ptid
))
7081 error (_("The current thread has terminated"));
7083 /* ... or from a spinning thread. */
7084 if (is_running (inferior_ptid
))
7085 error (_("Selected thread is running."));
7088 /* The $_siginfo convenience variable is a bit special. We don't know
7089 for sure the type of the value until we actually have a chance to
7090 fetch the data. The type can change depending on gdbarch, so it is
7091 also dependent on which thread you have selected.
7093 1. making $_siginfo be an internalvar that creates a new value on
7096 2. making the value of $_siginfo be an lval_computed value. */
7098 /* This function implements the lval_computed support for reading a
7102 siginfo_value_read (struct value
*v
)
7104 LONGEST transferred
;
7106 validate_siginfo_access ();
7109 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
7111 value_contents_all_raw (v
),
7113 TYPE_LENGTH (value_type (v
)));
7115 if (transferred
!= TYPE_LENGTH (value_type (v
)))
7116 error (_("Unable to read siginfo"));
7119 /* This function implements the lval_computed support for writing a
7123 siginfo_value_write (struct value
*v
, struct value
*fromval
)
7125 LONGEST transferred
;
7127 validate_siginfo_access ();
7129 transferred
= target_write (¤t_target
,
7130 TARGET_OBJECT_SIGNAL_INFO
,
7132 value_contents_all_raw (fromval
),
7134 TYPE_LENGTH (value_type (fromval
)));
7136 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
7137 error (_("Unable to write siginfo"));
7140 static const struct lval_funcs siginfo_value_funcs
=
7146 /* Return a new value with the correct type for the siginfo object of
7147 the current thread using architecture GDBARCH. Return a void value
7148 if there's no object available. */
7150 static struct value
*
7151 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
7154 if (target_has_stack
7155 && !ptid_equal (inferior_ptid
, null_ptid
)
7156 && gdbarch_get_siginfo_type_p (gdbarch
))
7158 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7160 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
7163 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
7167 /* infcall_suspend_state contains state about the program itself like its
7168 registers and any signal it received when it last stopped.
7169 This state must be restored regardless of how the inferior function call
7170 ends (either successfully, or after it hits a breakpoint or signal)
7171 if the program is to properly continue where it left off. */
7173 struct infcall_suspend_state
7175 struct thread_suspend_state thread_suspend
;
7176 #if 0 /* Currently unused and empty structures are not valid C. */
7177 struct inferior_suspend_state inferior_suspend
;
7182 struct regcache
*registers
;
7184 /* Format of SIGINFO_DATA or NULL if it is not present. */
7185 struct gdbarch
*siginfo_gdbarch
;
7187 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
7188 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
7189 content would be invalid. */
7190 gdb_byte
*siginfo_data
;
7193 struct infcall_suspend_state
*
7194 save_infcall_suspend_state (void)
7196 struct infcall_suspend_state
*inf_state
;
7197 struct thread_info
*tp
= inferior_thread ();
7199 struct inferior
*inf
= current_inferior ();
7201 struct regcache
*regcache
= get_current_regcache ();
7202 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7203 gdb_byte
*siginfo_data
= NULL
;
7205 if (gdbarch_get_siginfo_type_p (gdbarch
))
7207 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7208 size_t len
= TYPE_LENGTH (type
);
7209 struct cleanup
*back_to
;
7211 siginfo_data
= xmalloc (len
);
7212 back_to
= make_cleanup (xfree
, siginfo_data
);
7214 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7215 siginfo_data
, 0, len
) == len
)
7216 discard_cleanups (back_to
);
7219 /* Errors ignored. */
7220 do_cleanups (back_to
);
7221 siginfo_data
= NULL
;
7225 inf_state
= XCNEW (struct infcall_suspend_state
);
7229 inf_state
->siginfo_gdbarch
= gdbarch
;
7230 inf_state
->siginfo_data
= siginfo_data
;
7233 inf_state
->thread_suspend
= tp
->suspend
;
7234 #if 0 /* Currently unused and empty structures are not valid C. */
7235 inf_state
->inferior_suspend
= inf
->suspend
;
7238 /* run_inferior_call will not use the signal due to its `proceed' call with
7239 GDB_SIGNAL_0 anyway. */
7240 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7242 inf_state
->stop_pc
= stop_pc
;
7244 inf_state
->registers
= regcache_dup (regcache
);
7249 /* Restore inferior session state to INF_STATE. */
7252 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7254 struct thread_info
*tp
= inferior_thread ();
7256 struct inferior
*inf
= current_inferior ();
7258 struct regcache
*regcache
= get_current_regcache ();
7259 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7261 tp
->suspend
= inf_state
->thread_suspend
;
7262 #if 0 /* Currently unused and empty structures are not valid C. */
7263 inf
->suspend
= inf_state
->inferior_suspend
;
7266 stop_pc
= inf_state
->stop_pc
;
7268 if (inf_state
->siginfo_gdbarch
== gdbarch
)
7270 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7272 /* Errors ignored. */
7273 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7274 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
7277 /* The inferior can be gone if the user types "print exit(0)"
7278 (and perhaps other times). */
7279 if (target_has_execution
)
7280 /* NB: The register write goes through to the target. */
7281 regcache_cpy (regcache
, inf_state
->registers
);
7283 discard_infcall_suspend_state (inf_state
);
7287 do_restore_infcall_suspend_state_cleanup (void *state
)
7289 restore_infcall_suspend_state (state
);
7293 make_cleanup_restore_infcall_suspend_state
7294 (struct infcall_suspend_state
*inf_state
)
7296 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
7300 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7302 regcache_xfree (inf_state
->registers
);
7303 xfree (inf_state
->siginfo_data
);
7308 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
7310 return inf_state
->registers
;
7313 /* infcall_control_state contains state regarding gdb's control of the
7314 inferior itself like stepping control. It also contains session state like
7315 the user's currently selected frame. */
7317 struct infcall_control_state
7319 struct thread_control_state thread_control
;
7320 struct inferior_control_state inferior_control
;
7323 enum stop_stack_kind stop_stack_dummy
;
7324 int stopped_by_random_signal
;
7325 int stop_after_trap
;
7327 /* ID if the selected frame when the inferior function call was made. */
7328 struct frame_id selected_frame_id
;
7331 /* Save all of the information associated with the inferior<==>gdb
7334 struct infcall_control_state
*
7335 save_infcall_control_state (void)
7337 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
7338 struct thread_info
*tp
= inferior_thread ();
7339 struct inferior
*inf
= current_inferior ();
7341 inf_status
->thread_control
= tp
->control
;
7342 inf_status
->inferior_control
= inf
->control
;
7344 tp
->control
.step_resume_breakpoint
= NULL
;
7345 tp
->control
.exception_resume_breakpoint
= NULL
;
7347 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
7348 chain. If caller's caller is walking the chain, they'll be happier if we
7349 hand them back the original chain when restore_infcall_control_state is
7351 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
7354 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
7355 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
7356 inf_status
->stop_after_trap
= stop_after_trap
;
7358 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
7364 restore_selected_frame (void *args
)
7366 struct frame_id
*fid
= (struct frame_id
*) args
;
7367 struct frame_info
*frame
;
7369 frame
= frame_find_by_id (*fid
);
7371 /* If inf_status->selected_frame_id is NULL, there was no previously
7375 warning (_("Unable to restore previously selected frame."));
7379 select_frame (frame
);
7384 /* Restore inferior session state to INF_STATUS. */
7387 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
7389 struct thread_info
*tp
= inferior_thread ();
7390 struct inferior
*inf
= current_inferior ();
7392 if (tp
->control
.step_resume_breakpoint
)
7393 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
7395 if (tp
->control
.exception_resume_breakpoint
)
7396 tp
->control
.exception_resume_breakpoint
->disposition
7397 = disp_del_at_next_stop
;
7399 /* Handle the bpstat_copy of the chain. */
7400 bpstat_clear (&tp
->control
.stop_bpstat
);
7402 tp
->control
= inf_status
->thread_control
;
7403 inf
->control
= inf_status
->inferior_control
;
7406 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
7407 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
7408 stop_after_trap
= inf_status
->stop_after_trap
;
7410 if (target_has_stack
)
7412 /* The point of catch_errors is that if the stack is clobbered,
7413 walking the stack might encounter a garbage pointer and
7414 error() trying to dereference it. */
7416 (restore_selected_frame
, &inf_status
->selected_frame_id
,
7417 "Unable to restore previously selected frame:\n",
7418 RETURN_MASK_ERROR
) == 0)
7419 /* Error in restoring the selected frame. Select the innermost
7421 select_frame (get_current_frame ());
7428 do_restore_infcall_control_state_cleanup (void *sts
)
7430 restore_infcall_control_state (sts
);
7434 make_cleanup_restore_infcall_control_state
7435 (struct infcall_control_state
*inf_status
)
7437 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
7441 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
7443 if (inf_status
->thread_control
.step_resume_breakpoint
)
7444 inf_status
->thread_control
.step_resume_breakpoint
->disposition
7445 = disp_del_at_next_stop
;
7447 if (inf_status
->thread_control
.exception_resume_breakpoint
)
7448 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
7449 = disp_del_at_next_stop
;
7451 /* See save_infcall_control_state for info on stop_bpstat. */
7452 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
7457 /* restore_inferior_ptid() will be used by the cleanup machinery
7458 to restore the inferior_ptid value saved in a call to
7459 save_inferior_ptid(). */
7462 restore_inferior_ptid (void *arg
)
7464 ptid_t
*saved_ptid_ptr
= arg
;
7466 inferior_ptid
= *saved_ptid_ptr
;
7470 /* Save the value of inferior_ptid so that it may be restored by a
7471 later call to do_cleanups(). Returns the struct cleanup pointer
7472 needed for later doing the cleanup. */
7475 save_inferior_ptid (void)
7477 ptid_t
*saved_ptid_ptr
;
7479 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
7480 *saved_ptid_ptr
= inferior_ptid
;
7481 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
7487 clear_exit_convenience_vars (void)
7489 clear_internalvar (lookup_internalvar ("_exitsignal"));
7490 clear_internalvar (lookup_internalvar ("_exitcode"));
7494 /* User interface for reverse debugging:
7495 Set exec-direction / show exec-direction commands
7496 (returns error unless target implements to_set_exec_direction method). */
7498 int execution_direction
= EXEC_FORWARD
;
7499 static const char exec_forward
[] = "forward";
7500 static const char exec_reverse
[] = "reverse";
7501 static const char *exec_direction
= exec_forward
;
7502 static const char *const exec_direction_names
[] = {
7509 set_exec_direction_func (char *args
, int from_tty
,
7510 struct cmd_list_element
*cmd
)
7512 if (target_can_execute_reverse
)
7514 if (!strcmp (exec_direction
, exec_forward
))
7515 execution_direction
= EXEC_FORWARD
;
7516 else if (!strcmp (exec_direction
, exec_reverse
))
7517 execution_direction
= EXEC_REVERSE
;
7521 exec_direction
= exec_forward
;
7522 error (_("Target does not support this operation."));
7527 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7528 struct cmd_list_element
*cmd
, const char *value
)
7530 switch (execution_direction
) {
7532 fprintf_filtered (out
, _("Forward.\n"));
7535 fprintf_filtered (out
, _("Reverse.\n"));
7538 internal_error (__FILE__
, __LINE__
,
7539 _("bogus execution_direction value: %d"),
7540 (int) execution_direction
);
7545 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7546 struct cmd_list_element
*c
, const char *value
)
7548 fprintf_filtered (file
, _("Resuming the execution of threads "
7549 "of all processes is %s.\n"), value
);
7552 /* Implementation of `siginfo' variable. */
7554 static const struct internalvar_funcs siginfo_funcs
=
7562 _initialize_infrun (void)
7566 struct cmd_list_element
*c
;
7568 add_info ("signals", signals_info
, _("\
7569 What debugger does when program gets various signals.\n\
7570 Specify a signal as argument to print info on that signal only."));
7571 add_info_alias ("handle", "signals", 0);
7573 c
= add_com ("handle", class_run
, handle_command
, _("\
7574 Specify how to handle signals.\n\
7575 Usage: handle SIGNAL [ACTIONS]\n\
7576 Args are signals and actions to apply to those signals.\n\
7577 If no actions are specified, the current settings for the specified signals\n\
7578 will be displayed instead.\n\
7580 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7581 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7582 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7583 The special arg \"all\" is recognized to mean all signals except those\n\
7584 used by the debugger, typically SIGTRAP and SIGINT.\n\
7586 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7587 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7588 Stop means reenter debugger if this signal happens (implies print).\n\
7589 Print means print a message if this signal happens.\n\
7590 Pass means let program see this signal; otherwise program doesn't know.\n\
7591 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7592 Pass and Stop may be combined.\n\
7594 Multiple signals may be specified. Signal numbers and signal names\n\
7595 may be interspersed with actions, with the actions being performed for\n\
7596 all signals cumulatively specified."));
7597 set_cmd_completer (c
, handle_completer
);
7601 add_com ("lz", class_info
, signals_info
, _("\
7602 What debugger does when program gets various signals.\n\
7603 Specify a signal as argument to print info on that signal only."));
7604 add_com ("z", class_run
, xdb_handle_command
, _("\
7605 Specify how to handle a signal.\n\
7606 Args are signals and actions to apply to those signals.\n\
7607 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7608 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7609 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7610 The special arg \"all\" is recognized to mean all signals except those\n\
7611 used by the debugger, typically SIGTRAP and SIGINT.\n\
7612 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7613 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7614 nopass), \"Q\" (noprint)\n\
7615 Stop means reenter debugger if this signal happens (implies print).\n\
7616 Print means print a message if this signal happens.\n\
7617 Pass means let program see this signal; otherwise program doesn't know.\n\
7618 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7619 Pass and Stop may be combined."));
7623 stop_command
= add_cmd ("stop", class_obscure
,
7624 not_just_help_class_command
, _("\
7625 There is no `stop' command, but you can set a hook on `stop'.\n\
7626 This allows you to set a list of commands to be run each time execution\n\
7627 of the program stops."), &cmdlist
);
7629 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7630 Set inferior debugging."), _("\
7631 Show inferior debugging."), _("\
7632 When non-zero, inferior specific debugging is enabled."),
7635 &setdebuglist
, &showdebuglist
);
7637 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7638 &debug_displaced
, _("\
7639 Set displaced stepping debugging."), _("\
7640 Show displaced stepping debugging."), _("\
7641 When non-zero, displaced stepping specific debugging is enabled."),
7643 show_debug_displaced
,
7644 &setdebuglist
, &showdebuglist
);
7646 add_setshow_boolean_cmd ("non-stop", no_class
,
7648 Set whether gdb controls the inferior in non-stop mode."), _("\
7649 Show whether gdb controls the inferior in non-stop mode."), _("\
7650 When debugging a multi-threaded program and this setting is\n\
7651 off (the default, also called all-stop mode), when one thread stops\n\
7652 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7653 all other threads in the program while you interact with the thread of\n\
7654 interest. When you continue or step a thread, you can allow the other\n\
7655 threads to run, or have them remain stopped, but while you inspect any\n\
7656 thread's state, all threads stop.\n\
7658 In non-stop mode, when one thread stops, other threads can continue\n\
7659 to run freely. You'll be able to step each thread independently,\n\
7660 leave it stopped or free to run as needed."),
7666 numsigs
= (int) GDB_SIGNAL_LAST
;
7667 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7668 signal_print
= (unsigned char *)
7669 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7670 signal_program
= (unsigned char *)
7671 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7672 signal_catch
= (unsigned char *)
7673 xmalloc (sizeof (signal_catch
[0]) * numsigs
);
7674 signal_pass
= (unsigned char *)
7675 xmalloc (sizeof (signal_pass
[0]) * numsigs
);
7676 for (i
= 0; i
< numsigs
; i
++)
7679 signal_print
[i
] = 1;
7680 signal_program
[i
] = 1;
7681 signal_catch
[i
] = 0;
7684 /* Signals caused by debugger's own actions
7685 should not be given to the program afterwards. */
7686 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7687 signal_program
[GDB_SIGNAL_INT
] = 0;
7689 /* Signals that are not errors should not normally enter the debugger. */
7690 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7691 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7692 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7693 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7694 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7695 signal_print
[GDB_SIGNAL_PROF
] = 0;
7696 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7697 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7698 signal_stop
[GDB_SIGNAL_IO
] = 0;
7699 signal_print
[GDB_SIGNAL_IO
] = 0;
7700 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7701 signal_print
[GDB_SIGNAL_POLL
] = 0;
7702 signal_stop
[GDB_SIGNAL_URG
] = 0;
7703 signal_print
[GDB_SIGNAL_URG
] = 0;
7704 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7705 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7706 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7707 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7709 /* These signals are used internally by user-level thread
7710 implementations. (See signal(5) on Solaris.) Like the above
7711 signals, a healthy program receives and handles them as part of
7712 its normal operation. */
7713 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7714 signal_print
[GDB_SIGNAL_LWP
] = 0;
7715 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7716 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7717 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7718 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7720 /* Update cached state. */
7721 signal_cache_update (-1);
7723 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7724 &stop_on_solib_events
, _("\
7725 Set stopping for shared library events."), _("\
7726 Show stopping for shared library events."), _("\
7727 If nonzero, gdb will give control to the user when the dynamic linker\n\
7728 notifies gdb of shared library events. The most common event of interest\n\
7729 to the user would be loading/unloading of a new library."),
7730 set_stop_on_solib_events
,
7731 show_stop_on_solib_events
,
7732 &setlist
, &showlist
);
7734 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7735 follow_fork_mode_kind_names
,
7736 &follow_fork_mode_string
, _("\
7737 Set debugger response to a program call of fork or vfork."), _("\
7738 Show debugger response to a program call of fork or vfork."), _("\
7739 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7740 parent - the original process is debugged after a fork\n\
7741 child - the new process is debugged after a fork\n\
7742 The unfollowed process will continue to run.\n\
7743 By default, the debugger will follow the parent process."),
7745 show_follow_fork_mode_string
,
7746 &setlist
, &showlist
);
7748 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7749 follow_exec_mode_names
,
7750 &follow_exec_mode_string
, _("\
7751 Set debugger response to a program call of exec."), _("\
7752 Show debugger response to a program call of exec."), _("\
7753 An exec call replaces the program image of a process.\n\
7755 follow-exec-mode can be:\n\
7757 new - the debugger creates a new inferior and rebinds the process\n\
7758 to this new inferior. The program the process was running before\n\
7759 the exec call can be restarted afterwards by restarting the original\n\
7762 same - the debugger keeps the process bound to the same inferior.\n\
7763 The new executable image replaces the previous executable loaded in\n\
7764 the inferior. Restarting the inferior after the exec call restarts\n\
7765 the executable the process was running after the exec call.\n\
7767 By default, the debugger will use the same inferior."),
7769 show_follow_exec_mode_string
,
7770 &setlist
, &showlist
);
7772 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7773 scheduler_enums
, &scheduler_mode
, _("\
7774 Set mode for locking scheduler during execution."), _("\
7775 Show mode for locking scheduler during execution."), _("\
7776 off == no locking (threads may preempt at any time)\n\
7777 on == full locking (no thread except the current thread may run)\n\
7778 step == scheduler locked during every single-step operation.\n\
7779 In this mode, no other thread may run during a step command.\n\
7780 Other threads may run while stepping over a function call ('next')."),
7781 set_schedlock_func
, /* traps on target vector */
7782 show_scheduler_mode
,
7783 &setlist
, &showlist
);
7785 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7786 Set mode for resuming threads of all processes."), _("\
7787 Show mode for resuming threads of all processes."), _("\
7788 When on, execution commands (such as 'continue' or 'next') resume all\n\
7789 threads of all processes. When off (which is the default), execution\n\
7790 commands only resume the threads of the current process. The set of\n\
7791 threads that are resumed is further refined by the scheduler-locking\n\
7792 mode (see help set scheduler-locking)."),
7794 show_schedule_multiple
,
7795 &setlist
, &showlist
);
7797 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7798 Set mode of the step operation."), _("\
7799 Show mode of the step operation."), _("\
7800 When set, doing a step over a function without debug line information\n\
7801 will stop at the first instruction of that function. Otherwise, the\n\
7802 function is skipped and the step command stops at a different source line."),
7804 show_step_stop_if_no_debug
,
7805 &setlist
, &showlist
);
7807 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7808 &can_use_displaced_stepping
, _("\
7809 Set debugger's willingness to use displaced stepping."), _("\
7810 Show debugger's willingness to use displaced stepping."), _("\
7811 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7812 supported by the target architecture. If off, gdb will not use displaced\n\
7813 stepping to step over breakpoints, even if such is supported by the target\n\
7814 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7815 if the target architecture supports it and non-stop mode is active, but will not\n\
7816 use it in all-stop mode (see help set non-stop)."),
7818 show_can_use_displaced_stepping
,
7819 &setlist
, &showlist
);
7821 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7822 &exec_direction
, _("Set direction of execution.\n\
7823 Options are 'forward' or 'reverse'."),
7824 _("Show direction of execution (forward/reverse)."),
7825 _("Tells gdb whether to execute forward or backward."),
7826 set_exec_direction_func
, show_exec_direction_func
,
7827 &setlist
, &showlist
);
7829 /* Set/show detach-on-fork: user-settable mode. */
7831 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7832 Set whether gdb will detach the child of a fork."), _("\
7833 Show whether gdb will detach the child of a fork."), _("\
7834 Tells gdb whether to detach the child of a fork."),
7835 NULL
, NULL
, &setlist
, &showlist
);
7837 /* Set/show disable address space randomization mode. */
7839 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7840 &disable_randomization
, _("\
7841 Set disabling of debuggee's virtual address space randomization."), _("\
7842 Show disabling of debuggee's virtual address space randomization."), _("\
7843 When this mode is on (which is the default), randomization of the virtual\n\
7844 address space is disabled. Standalone programs run with the randomization\n\
7845 enabled by default on some platforms."),
7846 &set_disable_randomization
,
7847 &show_disable_randomization
,
7848 &setlist
, &showlist
);
7850 /* ptid initializations */
7851 inferior_ptid
= null_ptid
;
7852 target_last_wait_ptid
= minus_one_ptid
;
7854 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7855 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7856 observer_attach_thread_exit (infrun_thread_thread_exit
);
7857 observer_attach_inferior_exit (infrun_inferior_exit
);
7859 /* Explicitly create without lookup, since that tries to create a
7860 value with a void typed value, and when we get here, gdbarch
7861 isn't initialized yet. At this point, we're quite sure there
7862 isn't another convenience variable of the same name. */
7863 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7865 add_setshow_boolean_cmd ("observer", no_class
,
7866 &observer_mode_1
, _("\
7867 Set whether gdb controls the inferior in observer mode."), _("\
7868 Show whether gdb controls the inferior in observer mode."), _("\
7869 In observer mode, GDB can get data from the inferior, but not\n\
7870 affect its execution. Registers and memory may not be changed,\n\
7871 breakpoints may not be set, and the program cannot be interrupted\n\