1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2015 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 /* Prototypes for local functions */
66 static void signals_info (char *, int);
68 static void handle_command (char *, int);
70 static void sig_print_info (enum gdb_signal
);
72 static void sig_print_header (void);
74 static void resume_cleanups (void *);
76 static int hook_stop_stub (void *);
78 static int restore_selected_frame (void *);
80 static int follow_fork (void);
82 static int follow_fork_inferior (int follow_child
, int detach_fork
);
84 static void follow_inferior_reset_breakpoints (void);
86 static void set_schedlock_func (char *args
, int from_tty
,
87 struct cmd_list_element
*c
);
89 static int currently_stepping (struct thread_info
*tp
);
91 static void xdb_handle_command (char *args
, int from_tty
);
93 void _initialize_infrun (void);
95 void nullify_last_target_wait_ptid (void);
97 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
99 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
101 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
103 /* When set, stop the 'step' command if we enter a function which has
104 no line number information. The normal behavior is that we step
105 over such function. */
106 int step_stop_if_no_debug
= 0;
108 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
109 struct cmd_list_element
*c
, const char *value
)
111 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
114 /* In asynchronous mode, but simulating synchronous execution. */
116 int sync_execution
= 0;
118 /* proceed and normal_stop use this to notify the user when the
119 inferior stopped in a different thread than it had been running
122 static ptid_t previous_inferior_ptid
;
124 /* If set (default for legacy reasons), when following a fork, GDB
125 will detach from one of the fork branches, child or parent.
126 Exactly which branch is detached depends on 'set follow-fork-mode'
129 static int detach_fork
= 1;
131 int debug_displaced
= 0;
133 show_debug_displaced (struct ui_file
*file
, int from_tty
,
134 struct cmd_list_element
*c
, const char *value
)
136 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
139 unsigned int debug_infrun
= 0;
141 show_debug_infrun (struct ui_file
*file
, int from_tty
,
142 struct cmd_list_element
*c
, const char *value
)
144 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
148 /* Support for disabling address space randomization. */
150 int disable_randomization
= 1;
153 show_disable_randomization (struct ui_file
*file
, int from_tty
,
154 struct cmd_list_element
*c
, const char *value
)
156 if (target_supports_disable_randomization ())
157 fprintf_filtered (file
,
158 _("Disabling randomization of debuggee's "
159 "virtual address space is %s.\n"),
162 fputs_filtered (_("Disabling randomization of debuggee's "
163 "virtual address space is unsupported on\n"
164 "this platform.\n"), file
);
168 set_disable_randomization (char *args
, int from_tty
,
169 struct cmd_list_element
*c
)
171 if (!target_supports_disable_randomization ())
172 error (_("Disabling randomization of debuggee's "
173 "virtual address space is unsupported on\n"
177 /* User interface for non-stop mode. */
180 static int non_stop_1
= 0;
183 set_non_stop (char *args
, int from_tty
,
184 struct cmd_list_element
*c
)
186 if (target_has_execution
)
188 non_stop_1
= non_stop
;
189 error (_("Cannot change this setting while the inferior is running."));
192 non_stop
= non_stop_1
;
196 show_non_stop (struct ui_file
*file
, int from_tty
,
197 struct cmd_list_element
*c
, const char *value
)
199 fprintf_filtered (file
,
200 _("Controlling the inferior in non-stop mode is %s.\n"),
204 /* "Observer mode" is somewhat like a more extreme version of
205 non-stop, in which all GDB operations that might affect the
206 target's execution have been disabled. */
208 int observer_mode
= 0;
209 static int observer_mode_1
= 0;
212 set_observer_mode (char *args
, int from_tty
,
213 struct cmd_list_element
*c
)
215 if (target_has_execution
)
217 observer_mode_1
= observer_mode
;
218 error (_("Cannot change this setting while the inferior is running."));
221 observer_mode
= observer_mode_1
;
223 may_write_registers
= !observer_mode
;
224 may_write_memory
= !observer_mode
;
225 may_insert_breakpoints
= !observer_mode
;
226 may_insert_tracepoints
= !observer_mode
;
227 /* We can insert fast tracepoints in or out of observer mode,
228 but enable them if we're going into this mode. */
230 may_insert_fast_tracepoints
= 1;
231 may_stop
= !observer_mode
;
232 update_target_permissions ();
234 /* Going *into* observer mode we must force non-stop, then
235 going out we leave it that way. */
238 pagination_enabled
= 0;
239 non_stop
= non_stop_1
= 1;
243 printf_filtered (_("Observer mode is now %s.\n"),
244 (observer_mode
? "on" : "off"));
248 show_observer_mode (struct ui_file
*file
, int from_tty
,
249 struct cmd_list_element
*c
, const char *value
)
251 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
254 /* This updates the value of observer mode based on changes in
255 permissions. Note that we are deliberately ignoring the values of
256 may-write-registers and may-write-memory, since the user may have
257 reason to enable these during a session, for instance to turn on a
258 debugging-related global. */
261 update_observer_mode (void)
265 newval
= (!may_insert_breakpoints
266 && !may_insert_tracepoints
267 && may_insert_fast_tracepoints
271 /* Let the user know if things change. */
272 if (newval
!= observer_mode
)
273 printf_filtered (_("Observer mode is now %s.\n"),
274 (newval
? "on" : "off"));
276 observer_mode
= observer_mode_1
= newval
;
279 /* Tables of how to react to signals; the user sets them. */
281 static unsigned char *signal_stop
;
282 static unsigned char *signal_print
;
283 static unsigned char *signal_program
;
285 /* Table of signals that are registered with "catch signal". A
286 non-zero entry indicates that the signal is caught by some "catch
287 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
289 static unsigned char *signal_catch
;
291 /* Table of signals that the target may silently handle.
292 This is automatically determined from the flags above,
293 and simply cached here. */
294 static unsigned char *signal_pass
;
296 #define SET_SIGS(nsigs,sigs,flags) \
298 int signum = (nsigs); \
299 while (signum-- > 0) \
300 if ((sigs)[signum]) \
301 (flags)[signum] = 1; \
304 #define UNSET_SIGS(nsigs,sigs,flags) \
306 int signum = (nsigs); \
307 while (signum-- > 0) \
308 if ((sigs)[signum]) \
309 (flags)[signum] = 0; \
312 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
313 this function is to avoid exporting `signal_program'. */
316 update_signals_program_target (void)
318 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
321 /* Value to pass to target_resume() to cause all threads to resume. */
323 #define RESUME_ALL minus_one_ptid
325 /* Command list pointer for the "stop" placeholder. */
327 static struct cmd_list_element
*stop_command
;
329 /* Nonzero if we want to give control to the user when we're notified
330 of shared library events by the dynamic linker. */
331 int stop_on_solib_events
;
333 /* Enable or disable optional shared library event breakpoints
334 as appropriate when the above flag is changed. */
337 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
339 update_solib_breakpoints ();
343 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
344 struct cmd_list_element
*c
, const char *value
)
346 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
350 /* Nonzero means expecting a trace trap
351 and should stop the inferior and return silently when it happens. */
355 /* Save register contents here when executing a "finish" command or are
356 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
357 Thus this contains the return value from the called function (assuming
358 values are returned in a register). */
360 struct regcache
*stop_registers
;
362 /* Nonzero after stop if current stack frame should be printed. */
364 static int stop_print_frame
;
366 /* This is a cached copy of the pid/waitstatus of the last event
367 returned by target_wait()/deprecated_target_wait_hook(). This
368 information is returned by get_last_target_status(). */
369 static ptid_t target_last_wait_ptid
;
370 static struct target_waitstatus target_last_waitstatus
;
372 static void context_switch (ptid_t ptid
);
374 void init_thread_stepping_state (struct thread_info
*tss
);
376 static const char follow_fork_mode_child
[] = "child";
377 static const char follow_fork_mode_parent
[] = "parent";
379 static const char *const follow_fork_mode_kind_names
[] = {
380 follow_fork_mode_child
,
381 follow_fork_mode_parent
,
385 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
387 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
388 struct cmd_list_element
*c
, const char *value
)
390 fprintf_filtered (file
,
391 _("Debugger response to a program "
392 "call of fork or vfork is \"%s\".\n"),
397 /* Handle changes to the inferior list based on the type of fork,
398 which process is being followed, and whether the other process
399 should be detached. On entry inferior_ptid must be the ptid of
400 the fork parent. At return inferior_ptid is the ptid of the
401 followed inferior. */
404 follow_fork_inferior (int follow_child
, int detach_fork
)
407 ptid_t parent_ptid
, child_ptid
;
409 has_vforked
= (inferior_thread ()->pending_follow
.kind
410 == TARGET_WAITKIND_VFORKED
);
411 parent_ptid
= inferior_ptid
;
412 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
415 && !non_stop
/* Non-stop always resumes both branches. */
416 && (!target_is_async_p () || sync_execution
)
417 && !(follow_child
|| detach_fork
|| sched_multi
))
419 /* The parent stays blocked inside the vfork syscall until the
420 child execs or exits. If we don't let the child run, then
421 the parent stays blocked. If we're telling the parent to run
422 in the foreground, the user will not be able to ctrl-c to get
423 back the terminal, effectively hanging the debug session. */
424 fprintf_filtered (gdb_stderr
, _("\
425 Can not resume the parent process over vfork in the foreground while\n\
426 holding the child stopped. Try \"set detach-on-fork\" or \
427 \"set schedule-multiple\".\n"));
428 /* FIXME output string > 80 columns. */
434 /* Detach new forked process? */
437 struct cleanup
*old_chain
;
439 /* Before detaching from the child, remove all breakpoints
440 from it. If we forked, then this has already been taken
441 care of by infrun.c. If we vforked however, any
442 breakpoint inserted in the parent is visible in the
443 child, even those added while stopped in a vfork
444 catchpoint. This will remove the breakpoints from the
445 parent also, but they'll be reinserted below. */
448 /* Keep breakpoints list in sync. */
449 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
452 if (info_verbose
|| debug_infrun
)
454 target_terminal_ours_for_output ();
455 fprintf_filtered (gdb_stdlog
,
456 _("Detaching after %s from child %s.\n"),
457 has_vforked
? "vfork" : "fork",
458 target_pid_to_str (child_ptid
));
463 struct inferior
*parent_inf
, *child_inf
;
464 struct cleanup
*old_chain
;
466 /* Add process to GDB's tables. */
467 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
469 parent_inf
= current_inferior ();
470 child_inf
->attach_flag
= parent_inf
->attach_flag
;
471 copy_terminal_info (child_inf
, parent_inf
);
472 child_inf
->gdbarch
= parent_inf
->gdbarch
;
473 copy_inferior_target_desc_info (child_inf
, parent_inf
);
475 old_chain
= save_inferior_ptid ();
476 save_current_program_space ();
478 inferior_ptid
= child_ptid
;
479 add_thread (inferior_ptid
);
480 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
482 /* If this is a vfork child, then the address-space is
483 shared with the parent. */
486 child_inf
->pspace
= parent_inf
->pspace
;
487 child_inf
->aspace
= parent_inf
->aspace
;
489 /* The parent will be frozen until the child is done
490 with the shared region. Keep track of the
492 child_inf
->vfork_parent
= parent_inf
;
493 child_inf
->pending_detach
= 0;
494 parent_inf
->vfork_child
= child_inf
;
495 parent_inf
->pending_detach
= 0;
499 child_inf
->aspace
= new_address_space ();
500 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
501 child_inf
->removable
= 1;
502 set_current_program_space (child_inf
->pspace
);
503 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
505 /* Let the shared library layer (e.g., solib-svr4) learn
506 about this new process, relocate the cloned exec, pull
507 in shared libraries, and install the solib event
508 breakpoint. If a "cloned-VM" event was propagated
509 better throughout the core, this wouldn't be
511 solib_create_inferior_hook (0);
514 do_cleanups (old_chain
);
519 struct inferior
*parent_inf
;
521 parent_inf
= current_inferior ();
523 /* If we detached from the child, then we have to be careful
524 to not insert breakpoints in the parent until the child
525 is done with the shared memory region. However, if we're
526 staying attached to the child, then we can and should
527 insert breakpoints, so that we can debug it. A
528 subsequent child exec or exit is enough to know when does
529 the child stops using the parent's address space. */
530 parent_inf
->waiting_for_vfork_done
= detach_fork
;
531 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
536 /* Follow the child. */
537 struct inferior
*parent_inf
, *child_inf
;
538 struct program_space
*parent_pspace
;
540 if (info_verbose
|| debug_infrun
)
542 target_terminal_ours_for_output ();
543 fprintf_filtered (gdb_stdlog
,
544 _("Attaching after %s %s to child %s.\n"),
545 target_pid_to_str (parent_ptid
),
546 has_vforked
? "vfork" : "fork",
547 target_pid_to_str (child_ptid
));
550 /* Add the new inferior first, so that the target_detach below
551 doesn't unpush the target. */
553 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
555 parent_inf
= current_inferior ();
556 child_inf
->attach_flag
= parent_inf
->attach_flag
;
557 copy_terminal_info (child_inf
, parent_inf
);
558 child_inf
->gdbarch
= parent_inf
->gdbarch
;
559 copy_inferior_target_desc_info (child_inf
, parent_inf
);
561 parent_pspace
= parent_inf
->pspace
;
563 /* If we're vforking, we want to hold on to the parent until the
564 child exits or execs. At child exec or exit time we can
565 remove the old breakpoints from the parent and detach or
566 resume debugging it. Otherwise, detach the parent now; we'll
567 want to reuse it's program/address spaces, but we can't set
568 them to the child before removing breakpoints from the
569 parent, otherwise, the breakpoints module could decide to
570 remove breakpoints from the wrong process (since they'd be
571 assigned to the same address space). */
575 gdb_assert (child_inf
->vfork_parent
== NULL
);
576 gdb_assert (parent_inf
->vfork_child
== NULL
);
577 child_inf
->vfork_parent
= parent_inf
;
578 child_inf
->pending_detach
= 0;
579 parent_inf
->vfork_child
= child_inf
;
580 parent_inf
->pending_detach
= detach_fork
;
581 parent_inf
->waiting_for_vfork_done
= 0;
583 else if (detach_fork
)
585 if (info_verbose
|| debug_infrun
)
587 target_terminal_ours_for_output ();
588 fprintf_filtered (gdb_stdlog
,
589 _("Detaching after fork from "
591 target_pid_to_str (child_ptid
));
594 target_detach (NULL
, 0);
597 /* Note that the detach above makes PARENT_INF dangling. */
599 /* Add the child thread to the appropriate lists, and switch to
600 this new thread, before cloning the program space, and
601 informing the solib layer about this new process. */
603 inferior_ptid
= child_ptid
;
604 add_thread (inferior_ptid
);
606 /* If this is a vfork child, then the address-space is shared
607 with the parent. If we detached from the parent, then we can
608 reuse the parent's program/address spaces. */
609 if (has_vforked
|| detach_fork
)
611 child_inf
->pspace
= parent_pspace
;
612 child_inf
->aspace
= child_inf
->pspace
->aspace
;
616 child_inf
->aspace
= new_address_space ();
617 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
618 child_inf
->removable
= 1;
619 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
620 set_current_program_space (child_inf
->pspace
);
621 clone_program_space (child_inf
->pspace
, parent_pspace
);
623 /* Let the shared library layer (e.g., solib-svr4) learn
624 about this new process, relocate the cloned exec, pull in
625 shared libraries, and install the solib event breakpoint.
626 If a "cloned-VM" event was propagated better throughout
627 the core, this wouldn't be required. */
628 solib_create_inferior_hook (0);
632 return target_follow_fork (follow_child
, detach_fork
);
635 /* Tell the target to follow the fork we're stopped at. Returns true
636 if the inferior should be resumed; false, if the target for some
637 reason decided it's best not to resume. */
642 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
643 int should_resume
= 1;
644 struct thread_info
*tp
;
646 /* Copy user stepping state to the new inferior thread. FIXME: the
647 followed fork child thread should have a copy of most of the
648 parent thread structure's run control related fields, not just these.
649 Initialized to avoid "may be used uninitialized" warnings from gcc. */
650 struct breakpoint
*step_resume_breakpoint
= NULL
;
651 struct breakpoint
*exception_resume_breakpoint
= NULL
;
652 CORE_ADDR step_range_start
= 0;
653 CORE_ADDR step_range_end
= 0;
654 struct frame_id step_frame_id
= { 0 };
655 struct interp
*command_interp
= NULL
;
660 struct target_waitstatus wait_status
;
662 /* Get the last target status returned by target_wait(). */
663 get_last_target_status (&wait_ptid
, &wait_status
);
665 /* If not stopped at a fork event, then there's nothing else to
667 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
668 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
671 /* Check if we switched over from WAIT_PTID, since the event was
673 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
674 && !ptid_equal (inferior_ptid
, wait_ptid
))
676 /* We did. Switch back to WAIT_PTID thread, to tell the
677 target to follow it (in either direction). We'll
678 afterwards refuse to resume, and inform the user what
680 switch_to_thread (wait_ptid
);
685 tp
= inferior_thread ();
687 /* If there were any forks/vforks that were caught and are now to be
688 followed, then do so now. */
689 switch (tp
->pending_follow
.kind
)
691 case TARGET_WAITKIND_FORKED
:
692 case TARGET_WAITKIND_VFORKED
:
694 ptid_t parent
, child
;
696 /* If the user did a next/step, etc, over a fork call,
697 preserve the stepping state in the fork child. */
698 if (follow_child
&& should_resume
)
700 step_resume_breakpoint
= clone_momentary_breakpoint
701 (tp
->control
.step_resume_breakpoint
);
702 step_range_start
= tp
->control
.step_range_start
;
703 step_range_end
= tp
->control
.step_range_end
;
704 step_frame_id
= tp
->control
.step_frame_id
;
705 exception_resume_breakpoint
706 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
707 command_interp
= tp
->control
.command_interp
;
709 /* For now, delete the parent's sr breakpoint, otherwise,
710 parent/child sr breakpoints are considered duplicates,
711 and the child version will not be installed. Remove
712 this when the breakpoints module becomes aware of
713 inferiors and address spaces. */
714 delete_step_resume_breakpoint (tp
);
715 tp
->control
.step_range_start
= 0;
716 tp
->control
.step_range_end
= 0;
717 tp
->control
.step_frame_id
= null_frame_id
;
718 delete_exception_resume_breakpoint (tp
);
719 tp
->control
.command_interp
= NULL
;
722 parent
= inferior_ptid
;
723 child
= tp
->pending_follow
.value
.related_pid
;
725 /* Set up inferior(s) as specified by the caller, and tell the
726 target to do whatever is necessary to follow either parent
728 if (follow_fork_inferior (follow_child
, detach_fork
))
730 /* Target refused to follow, or there's some other reason
731 we shouldn't resume. */
736 /* This pending follow fork event is now handled, one way
737 or another. The previous selected thread may be gone
738 from the lists by now, but if it is still around, need
739 to clear the pending follow request. */
740 tp
= find_thread_ptid (parent
);
742 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
744 /* This makes sure we don't try to apply the "Switched
745 over from WAIT_PID" logic above. */
746 nullify_last_target_wait_ptid ();
748 /* If we followed the child, switch to it... */
751 switch_to_thread (child
);
753 /* ... and preserve the stepping state, in case the
754 user was stepping over the fork call. */
757 tp
= inferior_thread ();
758 tp
->control
.step_resume_breakpoint
759 = step_resume_breakpoint
;
760 tp
->control
.step_range_start
= step_range_start
;
761 tp
->control
.step_range_end
= step_range_end
;
762 tp
->control
.step_frame_id
= step_frame_id
;
763 tp
->control
.exception_resume_breakpoint
764 = exception_resume_breakpoint
;
765 tp
->control
.command_interp
= command_interp
;
769 /* If we get here, it was because we're trying to
770 resume from a fork catchpoint, but, the user
771 has switched threads away from the thread that
772 forked. In that case, the resume command
773 issued is most likely not applicable to the
774 child, so just warn, and refuse to resume. */
775 warning (_("Not resuming: switched threads "
776 "before following fork child.\n"));
779 /* Reset breakpoints in the child as appropriate. */
780 follow_inferior_reset_breakpoints ();
783 switch_to_thread (parent
);
787 case TARGET_WAITKIND_SPURIOUS
:
788 /* Nothing to follow. */
791 internal_error (__FILE__
, __LINE__
,
792 "Unexpected pending_follow.kind %d\n",
793 tp
->pending_follow
.kind
);
797 return should_resume
;
801 follow_inferior_reset_breakpoints (void)
803 struct thread_info
*tp
= inferior_thread ();
805 /* Was there a step_resume breakpoint? (There was if the user
806 did a "next" at the fork() call.) If so, explicitly reset its
807 thread number. Cloned step_resume breakpoints are disabled on
808 creation, so enable it here now that it is associated with the
811 step_resumes are a form of bp that are made to be per-thread.
812 Since we created the step_resume bp when the parent process
813 was being debugged, and now are switching to the child process,
814 from the breakpoint package's viewpoint, that's a switch of
815 "threads". We must update the bp's notion of which thread
816 it is for, or it'll be ignored when it triggers. */
818 if (tp
->control
.step_resume_breakpoint
)
820 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
821 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
824 /* Treat exception_resume breakpoints like step_resume breakpoints. */
825 if (tp
->control
.exception_resume_breakpoint
)
827 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
828 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
831 /* Reinsert all breakpoints in the child. The user may have set
832 breakpoints after catching the fork, in which case those
833 were never set in the child, but only in the parent. This makes
834 sure the inserted breakpoints match the breakpoint list. */
836 breakpoint_re_set ();
837 insert_breakpoints ();
840 /* The child has exited or execed: resume threads of the parent the
841 user wanted to be executing. */
844 proceed_after_vfork_done (struct thread_info
*thread
,
847 int pid
= * (int *) arg
;
849 if (ptid_get_pid (thread
->ptid
) == pid
850 && is_running (thread
->ptid
)
851 && !is_executing (thread
->ptid
)
852 && !thread
->stop_requested
853 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
856 fprintf_unfiltered (gdb_stdlog
,
857 "infrun: resuming vfork parent thread %s\n",
858 target_pid_to_str (thread
->ptid
));
860 switch_to_thread (thread
->ptid
);
861 clear_proceed_status (0);
862 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
, 0);
868 /* Called whenever we notice an exec or exit event, to handle
869 detaching or resuming a vfork parent. */
872 handle_vfork_child_exec_or_exit (int exec
)
874 struct inferior
*inf
= current_inferior ();
876 if (inf
->vfork_parent
)
878 int resume_parent
= -1;
880 /* This exec or exit marks the end of the shared memory region
881 between the parent and the child. If the user wanted to
882 detach from the parent, now is the time. */
884 if (inf
->vfork_parent
->pending_detach
)
886 struct thread_info
*tp
;
887 struct cleanup
*old_chain
;
888 struct program_space
*pspace
;
889 struct address_space
*aspace
;
891 /* follow-fork child, detach-on-fork on. */
893 inf
->vfork_parent
->pending_detach
= 0;
897 /* If we're handling a child exit, then inferior_ptid
898 points at the inferior's pid, not to a thread. */
899 old_chain
= save_inferior_ptid ();
900 save_current_program_space ();
901 save_current_inferior ();
904 old_chain
= save_current_space_and_thread ();
906 /* We're letting loose of the parent. */
907 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
908 switch_to_thread (tp
->ptid
);
910 /* We're about to detach from the parent, which implicitly
911 removes breakpoints from its address space. There's a
912 catch here: we want to reuse the spaces for the child,
913 but, parent/child are still sharing the pspace at this
914 point, although the exec in reality makes the kernel give
915 the child a fresh set of new pages. The problem here is
916 that the breakpoints module being unaware of this, would
917 likely chose the child process to write to the parent
918 address space. Swapping the child temporarily away from
919 the spaces has the desired effect. Yes, this is "sort
922 pspace
= inf
->pspace
;
923 aspace
= inf
->aspace
;
927 if (debug_infrun
|| info_verbose
)
929 target_terminal_ours_for_output ();
933 fprintf_filtered (gdb_stdlog
,
934 _("Detaching vfork parent process "
935 "%d after child exec.\n"),
936 inf
->vfork_parent
->pid
);
940 fprintf_filtered (gdb_stdlog
,
941 _("Detaching vfork parent process "
942 "%d after child exit.\n"),
943 inf
->vfork_parent
->pid
);
947 target_detach (NULL
, 0);
950 inf
->pspace
= pspace
;
951 inf
->aspace
= aspace
;
953 do_cleanups (old_chain
);
957 /* We're staying attached to the parent, so, really give the
958 child a new address space. */
959 inf
->pspace
= add_program_space (maybe_new_address_space ());
960 inf
->aspace
= inf
->pspace
->aspace
;
962 set_current_program_space (inf
->pspace
);
964 resume_parent
= inf
->vfork_parent
->pid
;
966 /* Break the bonds. */
967 inf
->vfork_parent
->vfork_child
= NULL
;
971 struct cleanup
*old_chain
;
972 struct program_space
*pspace
;
974 /* If this is a vfork child exiting, then the pspace and
975 aspaces were shared with the parent. Since we're
976 reporting the process exit, we'll be mourning all that is
977 found in the address space, and switching to null_ptid,
978 preparing to start a new inferior. But, since we don't
979 want to clobber the parent's address/program spaces, we
980 go ahead and create a new one for this exiting
983 /* Switch to null_ptid, so that clone_program_space doesn't want
984 to read the selected frame of a dead process. */
985 old_chain
= save_inferior_ptid ();
986 inferior_ptid
= null_ptid
;
988 /* This inferior is dead, so avoid giving the breakpoints
989 module the option to write through to it (cloning a
990 program space resets breakpoints). */
993 pspace
= add_program_space (maybe_new_address_space ());
994 set_current_program_space (pspace
);
996 inf
->symfile_flags
= SYMFILE_NO_READ
;
997 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
998 inf
->pspace
= pspace
;
999 inf
->aspace
= pspace
->aspace
;
1001 /* Put back inferior_ptid. We'll continue mourning this
1003 do_cleanups (old_chain
);
1005 resume_parent
= inf
->vfork_parent
->pid
;
1006 /* Break the bonds. */
1007 inf
->vfork_parent
->vfork_child
= NULL
;
1010 inf
->vfork_parent
= NULL
;
1012 gdb_assert (current_program_space
== inf
->pspace
);
1014 if (non_stop
&& resume_parent
!= -1)
1016 /* If the user wanted the parent to be running, let it go
1018 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1021 fprintf_unfiltered (gdb_stdlog
,
1022 "infrun: resuming vfork parent process %d\n",
1025 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1027 do_cleanups (old_chain
);
1032 /* Enum strings for "set|show follow-exec-mode". */
1034 static const char follow_exec_mode_new
[] = "new";
1035 static const char follow_exec_mode_same
[] = "same";
1036 static const char *const follow_exec_mode_names
[] =
1038 follow_exec_mode_new
,
1039 follow_exec_mode_same
,
1043 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1045 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1046 struct cmd_list_element
*c
, const char *value
)
1048 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1051 /* EXECD_PATHNAME is assumed to be non-NULL. */
1054 follow_exec (ptid_t ptid
, char *execd_pathname
)
1056 struct thread_info
*th
, *tmp
;
1057 struct inferior
*inf
= current_inferior ();
1058 int pid
= ptid_get_pid (ptid
);
1060 /* This is an exec event that we actually wish to pay attention to.
1061 Refresh our symbol table to the newly exec'd program, remove any
1062 momentary bp's, etc.
1064 If there are breakpoints, they aren't really inserted now,
1065 since the exec() transformed our inferior into a fresh set
1068 We want to preserve symbolic breakpoints on the list, since
1069 we have hopes that they can be reset after the new a.out's
1070 symbol table is read.
1072 However, any "raw" breakpoints must be removed from the list
1073 (e.g., the solib bp's), since their address is probably invalid
1076 And, we DON'T want to call delete_breakpoints() here, since
1077 that may write the bp's "shadow contents" (the instruction
1078 value that was overwritten witha TRAP instruction). Since
1079 we now have a new a.out, those shadow contents aren't valid. */
1081 mark_breakpoints_out ();
1083 /* The target reports the exec event to the main thread, even if
1084 some other thread does the exec, and even if the main thread was
1085 stopped or already gone. We may still have non-leader threads of
1086 the process on our list. E.g., on targets that don't have thread
1087 exit events (like remote); or on native Linux in non-stop mode if
1088 there were only two threads in the inferior and the non-leader
1089 one is the one that execs (and nothing forces an update of the
1090 thread list up to here). When debugging remotely, it's best to
1091 avoid extra traffic, when possible, so avoid syncing the thread
1092 list with the target, and instead go ahead and delete all threads
1093 of the process but one that reported the event. Note this must
1094 be done before calling update_breakpoints_after_exec, as
1095 otherwise clearing the threads' resources would reference stale
1096 thread breakpoints -- it may have been one of these threads that
1097 stepped across the exec. We could just clear their stepping
1098 states, but as long as we're iterating, might as well delete
1099 them. Deleting them now rather than at the next user-visible
1100 stop provides a nicer sequence of events for user and MI
1102 ALL_NON_EXITED_THREADS_SAFE (th
, tmp
)
1103 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1104 delete_thread (th
->ptid
);
1106 /* We also need to clear any left over stale state for the
1107 leader/event thread. E.g., if there was any step-resume
1108 breakpoint or similar, it's gone now. We cannot truly
1109 step-to-next statement through an exec(). */
1110 th
= inferior_thread ();
1111 th
->control
.step_resume_breakpoint
= NULL
;
1112 th
->control
.exception_resume_breakpoint
= NULL
;
1113 th
->control
.single_step_breakpoints
= NULL
;
1114 th
->control
.step_range_start
= 0;
1115 th
->control
.step_range_end
= 0;
1117 /* The user may have had the main thread held stopped in the
1118 previous image (e.g., schedlock on, or non-stop). Release
1120 th
->stop_requested
= 0;
1122 update_breakpoints_after_exec ();
1124 /* What is this a.out's name? */
1125 printf_unfiltered (_("%s is executing new program: %s\n"),
1126 target_pid_to_str (inferior_ptid
),
1129 /* We've followed the inferior through an exec. Therefore, the
1130 inferior has essentially been killed & reborn. */
1132 gdb_flush (gdb_stdout
);
1134 breakpoint_init_inferior (inf_execd
);
1136 if (gdb_sysroot
&& *gdb_sysroot
)
1138 char *name
= alloca (strlen (gdb_sysroot
)
1139 + strlen (execd_pathname
)
1142 strcpy (name
, gdb_sysroot
);
1143 strcat (name
, execd_pathname
);
1144 execd_pathname
= name
;
1147 /* Reset the shared library package. This ensures that we get a
1148 shlib event when the child reaches "_start", at which point the
1149 dld will have had a chance to initialize the child. */
1150 /* Also, loading a symbol file below may trigger symbol lookups, and
1151 we don't want those to be satisfied by the libraries of the
1152 previous incarnation of this process. */
1153 no_shared_libraries (NULL
, 0);
1155 if (follow_exec_mode_string
== follow_exec_mode_new
)
1157 struct program_space
*pspace
;
1159 /* The user wants to keep the old inferior and program spaces
1160 around. Create a new fresh one, and switch to it. */
1162 inf
= add_inferior (current_inferior ()->pid
);
1163 pspace
= add_program_space (maybe_new_address_space ());
1164 inf
->pspace
= pspace
;
1165 inf
->aspace
= pspace
->aspace
;
1167 exit_inferior_num_silent (current_inferior ()->num
);
1169 set_current_inferior (inf
);
1170 set_current_program_space (pspace
);
1174 /* The old description may no longer be fit for the new image.
1175 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1176 old description; we'll read a new one below. No need to do
1177 this on "follow-exec-mode new", as the old inferior stays
1178 around (its description is later cleared/refetched on
1180 target_clear_description ();
1183 gdb_assert (current_program_space
== inf
->pspace
);
1185 /* That a.out is now the one to use. */
1186 exec_file_attach (execd_pathname
, 0);
1188 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1189 (Position Independent Executable) main symbol file will get applied by
1190 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1191 the breakpoints with the zero displacement. */
1193 symbol_file_add (execd_pathname
,
1195 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1198 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1199 set_initial_language ();
1201 /* If the target can specify a description, read it. Must do this
1202 after flipping to the new executable (because the target supplied
1203 description must be compatible with the executable's
1204 architecture, and the old executable may e.g., be 32-bit, while
1205 the new one 64-bit), and before anything involving memory or
1207 target_find_description ();
1209 solib_create_inferior_hook (0);
1211 jit_inferior_created_hook ();
1213 breakpoint_re_set ();
1215 /* Reinsert all breakpoints. (Those which were symbolic have
1216 been reset to the proper address in the new a.out, thanks
1217 to symbol_file_command...). */
1218 insert_breakpoints ();
1220 /* The next resume of this inferior should bring it to the shlib
1221 startup breakpoints. (If the user had also set bp's on
1222 "main" from the old (parent) process, then they'll auto-
1223 matically get reset there in the new process.). */
1226 /* Info about an instruction that is being stepped over. */
1228 struct step_over_info
1230 /* If we're stepping past a breakpoint, this is the address space
1231 and address of the instruction the breakpoint is set at. We'll
1232 skip inserting all breakpoints here. Valid iff ASPACE is
1234 struct address_space
*aspace
;
1237 /* The instruction being stepped over triggers a nonsteppable
1238 watchpoint. If true, we'll skip inserting watchpoints. */
1239 int nonsteppable_watchpoint_p
;
1242 /* The step-over info of the location that is being stepped over.
1244 Note that with async/breakpoint always-inserted mode, a user might
1245 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1246 being stepped over. As setting a new breakpoint inserts all
1247 breakpoints, we need to make sure the breakpoint being stepped over
1248 isn't inserted then. We do that by only clearing the step-over
1249 info when the step-over is actually finished (or aborted).
1251 Presently GDB can only step over one breakpoint at any given time.
1252 Given threads that can't run code in the same address space as the
1253 breakpoint's can't really miss the breakpoint, GDB could be taught
1254 to step-over at most one breakpoint per address space (so this info
1255 could move to the address space object if/when GDB is extended).
1256 The set of breakpoints being stepped over will normally be much
1257 smaller than the set of all breakpoints, so a flag in the
1258 breakpoint location structure would be wasteful. A separate list
1259 also saves complexity and run-time, as otherwise we'd have to go
1260 through all breakpoint locations clearing their flag whenever we
1261 start a new sequence. Similar considerations weigh against storing
1262 this info in the thread object. Plus, not all step overs actually
1263 have breakpoint locations -- e.g., stepping past a single-step
1264 breakpoint, or stepping to complete a non-continuable
1266 static struct step_over_info step_over_info
;
1268 /* Record the address of the breakpoint/instruction we're currently
1272 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1273 int nonsteppable_watchpoint_p
)
1275 step_over_info
.aspace
= aspace
;
1276 step_over_info
.address
= address
;
1277 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1280 /* Called when we're not longer stepping over a breakpoint / an
1281 instruction, so all breakpoints are free to be (re)inserted. */
1284 clear_step_over_info (void)
1286 step_over_info
.aspace
= NULL
;
1287 step_over_info
.address
= 0;
1288 step_over_info
.nonsteppable_watchpoint_p
= 0;
1294 stepping_past_instruction_at (struct address_space
*aspace
,
1297 return (step_over_info
.aspace
!= NULL
1298 && breakpoint_address_match (aspace
, address
,
1299 step_over_info
.aspace
,
1300 step_over_info
.address
));
1306 stepping_past_nonsteppable_watchpoint (void)
1308 return step_over_info
.nonsteppable_watchpoint_p
;
1311 /* Returns true if step-over info is valid. */
1314 step_over_info_valid_p (void)
1316 return (step_over_info
.aspace
!= NULL
1317 || stepping_past_nonsteppable_watchpoint ());
1321 /* Displaced stepping. */
1323 /* In non-stop debugging mode, we must take special care to manage
1324 breakpoints properly; in particular, the traditional strategy for
1325 stepping a thread past a breakpoint it has hit is unsuitable.
1326 'Displaced stepping' is a tactic for stepping one thread past a
1327 breakpoint it has hit while ensuring that other threads running
1328 concurrently will hit the breakpoint as they should.
1330 The traditional way to step a thread T off a breakpoint in a
1331 multi-threaded program in all-stop mode is as follows:
1333 a0) Initially, all threads are stopped, and breakpoints are not
1335 a1) We single-step T, leaving breakpoints uninserted.
1336 a2) We insert breakpoints, and resume all threads.
1338 In non-stop debugging, however, this strategy is unsuitable: we
1339 don't want to have to stop all threads in the system in order to
1340 continue or step T past a breakpoint. Instead, we use displaced
1343 n0) Initially, T is stopped, other threads are running, and
1344 breakpoints are inserted.
1345 n1) We copy the instruction "under" the breakpoint to a separate
1346 location, outside the main code stream, making any adjustments
1347 to the instruction, register, and memory state as directed by
1349 n2) We single-step T over the instruction at its new location.
1350 n3) We adjust the resulting register and memory state as directed
1351 by T's architecture. This includes resetting T's PC to point
1352 back into the main instruction stream.
1355 This approach depends on the following gdbarch methods:
1357 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1358 indicate where to copy the instruction, and how much space must
1359 be reserved there. We use these in step n1.
1361 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1362 address, and makes any necessary adjustments to the instruction,
1363 register contents, and memory. We use this in step n1.
1365 - gdbarch_displaced_step_fixup adjusts registers and memory after
1366 we have successfuly single-stepped the instruction, to yield the
1367 same effect the instruction would have had if we had executed it
1368 at its original address. We use this in step n3.
1370 - gdbarch_displaced_step_free_closure provides cleanup.
1372 The gdbarch_displaced_step_copy_insn and
1373 gdbarch_displaced_step_fixup functions must be written so that
1374 copying an instruction with gdbarch_displaced_step_copy_insn,
1375 single-stepping across the copied instruction, and then applying
1376 gdbarch_displaced_insn_fixup should have the same effects on the
1377 thread's memory and registers as stepping the instruction in place
1378 would have. Exactly which responsibilities fall to the copy and
1379 which fall to the fixup is up to the author of those functions.
1381 See the comments in gdbarch.sh for details.
1383 Note that displaced stepping and software single-step cannot
1384 currently be used in combination, although with some care I think
1385 they could be made to. Software single-step works by placing
1386 breakpoints on all possible subsequent instructions; if the
1387 displaced instruction is a PC-relative jump, those breakpoints
1388 could fall in very strange places --- on pages that aren't
1389 executable, or at addresses that are not proper instruction
1390 boundaries. (We do generally let other threads run while we wait
1391 to hit the software single-step breakpoint, and they might
1392 encounter such a corrupted instruction.) One way to work around
1393 this would be to have gdbarch_displaced_step_copy_insn fully
1394 simulate the effect of PC-relative instructions (and return NULL)
1395 on architectures that use software single-stepping.
1397 In non-stop mode, we can have independent and simultaneous step
1398 requests, so more than one thread may need to simultaneously step
1399 over a breakpoint. The current implementation assumes there is
1400 only one scratch space per process. In this case, we have to
1401 serialize access to the scratch space. If thread A wants to step
1402 over a breakpoint, but we are currently waiting for some other
1403 thread to complete a displaced step, we leave thread A stopped and
1404 place it in the displaced_step_request_queue. Whenever a displaced
1405 step finishes, we pick the next thread in the queue and start a new
1406 displaced step operation on it. See displaced_step_prepare and
1407 displaced_step_fixup for details. */
1409 struct displaced_step_request
1412 struct displaced_step_request
*next
;
1415 /* Per-inferior displaced stepping state. */
1416 struct displaced_step_inferior_state
1418 /* Pointer to next in linked list. */
1419 struct displaced_step_inferior_state
*next
;
1421 /* The process this displaced step state refers to. */
1424 /* A queue of pending displaced stepping requests. One entry per
1425 thread that needs to do a displaced step. */
1426 struct displaced_step_request
*step_request_queue
;
1428 /* If this is not null_ptid, this is the thread carrying out a
1429 displaced single-step in process PID. This thread's state will
1430 require fixing up once it has completed its step. */
1433 /* The architecture the thread had when we stepped it. */
1434 struct gdbarch
*step_gdbarch
;
1436 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1437 for post-step cleanup. */
1438 struct displaced_step_closure
*step_closure
;
1440 /* The address of the original instruction, and the copy we
1442 CORE_ADDR step_original
, step_copy
;
1444 /* Saved contents of copy area. */
1445 gdb_byte
*step_saved_copy
;
1448 /* The list of states of processes involved in displaced stepping
1450 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1452 /* Get the displaced stepping state of process PID. */
1454 static struct displaced_step_inferior_state
*
1455 get_displaced_stepping_state (int pid
)
1457 struct displaced_step_inferior_state
*state
;
1459 for (state
= displaced_step_inferior_states
;
1461 state
= state
->next
)
1462 if (state
->pid
== pid
)
1468 /* Add a new displaced stepping state for process PID to the displaced
1469 stepping state list, or return a pointer to an already existing
1470 entry, if it already exists. Never returns NULL. */
1472 static struct displaced_step_inferior_state
*
1473 add_displaced_stepping_state (int pid
)
1475 struct displaced_step_inferior_state
*state
;
1477 for (state
= displaced_step_inferior_states
;
1479 state
= state
->next
)
1480 if (state
->pid
== pid
)
1483 state
= xcalloc (1, sizeof (*state
));
1485 state
->next
= displaced_step_inferior_states
;
1486 displaced_step_inferior_states
= state
;
1491 /* If inferior is in displaced stepping, and ADDR equals to starting address
1492 of copy area, return corresponding displaced_step_closure. Otherwise,
1495 struct displaced_step_closure
*
1496 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1498 struct displaced_step_inferior_state
*displaced
1499 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1501 /* If checking the mode of displaced instruction in copy area. */
1502 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1503 && (displaced
->step_copy
== addr
))
1504 return displaced
->step_closure
;
1509 /* Remove the displaced stepping state of process PID. */
1512 remove_displaced_stepping_state (int pid
)
1514 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1516 gdb_assert (pid
!= 0);
1518 it
= displaced_step_inferior_states
;
1519 prev_next_p
= &displaced_step_inferior_states
;
1524 *prev_next_p
= it
->next
;
1529 prev_next_p
= &it
->next
;
1535 infrun_inferior_exit (struct inferior
*inf
)
1537 remove_displaced_stepping_state (inf
->pid
);
1540 /* If ON, and the architecture supports it, GDB will use displaced
1541 stepping to step over breakpoints. If OFF, or if the architecture
1542 doesn't support it, GDB will instead use the traditional
1543 hold-and-step approach. If AUTO (which is the default), GDB will
1544 decide which technique to use to step over breakpoints depending on
1545 which of all-stop or non-stop mode is active --- displaced stepping
1546 in non-stop mode; hold-and-step in all-stop mode. */
1548 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1551 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1552 struct cmd_list_element
*c
,
1555 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1556 fprintf_filtered (file
,
1557 _("Debugger's willingness to use displaced stepping "
1558 "to step over breakpoints is %s (currently %s).\n"),
1559 value
, non_stop
? "on" : "off");
1561 fprintf_filtered (file
,
1562 _("Debugger's willingness to use displaced stepping "
1563 "to step over breakpoints is %s.\n"), value
);
1566 /* Return non-zero if displaced stepping can/should be used to step
1567 over breakpoints. */
1570 use_displaced_stepping (struct gdbarch
*gdbarch
)
1572 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
&& non_stop
)
1573 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1574 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1575 && find_record_target () == NULL
);
1578 /* Clean out any stray displaced stepping state. */
1580 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1582 /* Indicate that there is no cleanup pending. */
1583 displaced
->step_ptid
= null_ptid
;
1585 if (displaced
->step_closure
)
1587 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1588 displaced
->step_closure
);
1589 displaced
->step_closure
= NULL
;
1594 displaced_step_clear_cleanup (void *arg
)
1596 struct displaced_step_inferior_state
*state
= arg
;
1598 displaced_step_clear (state
);
1601 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1603 displaced_step_dump_bytes (struct ui_file
*file
,
1604 const gdb_byte
*buf
,
1609 for (i
= 0; i
< len
; i
++)
1610 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1611 fputs_unfiltered ("\n", file
);
1614 /* Prepare to single-step, using displaced stepping.
1616 Note that we cannot use displaced stepping when we have a signal to
1617 deliver. If we have a signal to deliver and an instruction to step
1618 over, then after the step, there will be no indication from the
1619 target whether the thread entered a signal handler or ignored the
1620 signal and stepped over the instruction successfully --- both cases
1621 result in a simple SIGTRAP. In the first case we mustn't do a
1622 fixup, and in the second case we must --- but we can't tell which.
1623 Comments in the code for 'random signals' in handle_inferior_event
1624 explain how we handle this case instead.
1626 Returns 1 if preparing was successful -- this thread is going to be
1627 stepped now; or 0 if displaced stepping this thread got queued. */
1629 displaced_step_prepare (ptid_t ptid
)
1631 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1632 struct thread_info
*tp
= find_thread_ptid (ptid
);
1633 struct regcache
*regcache
= get_thread_regcache (ptid
);
1634 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1635 CORE_ADDR original
, copy
;
1637 struct displaced_step_closure
*closure
;
1638 struct displaced_step_inferior_state
*displaced
;
1641 /* We should never reach this function if the architecture does not
1642 support displaced stepping. */
1643 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1645 /* Disable range stepping while executing in the scratch pad. We
1646 want a single-step even if executing the displaced instruction in
1647 the scratch buffer lands within the stepping range (e.g., a
1649 tp
->control
.may_range_step
= 0;
1651 /* We have to displaced step one thread at a time, as we only have
1652 access to a single scratch space per inferior. */
1654 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1656 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1658 /* Already waiting for a displaced step to finish. Defer this
1659 request and place in queue. */
1660 struct displaced_step_request
*req
, *new_req
;
1662 if (debug_displaced
)
1663 fprintf_unfiltered (gdb_stdlog
,
1664 "displaced: defering step of %s\n",
1665 target_pid_to_str (ptid
));
1667 new_req
= xmalloc (sizeof (*new_req
));
1668 new_req
->ptid
= ptid
;
1669 new_req
->next
= NULL
;
1671 if (displaced
->step_request_queue
)
1673 for (req
= displaced
->step_request_queue
;
1677 req
->next
= new_req
;
1680 displaced
->step_request_queue
= new_req
;
1686 if (debug_displaced
)
1687 fprintf_unfiltered (gdb_stdlog
,
1688 "displaced: stepping %s now\n",
1689 target_pid_to_str (ptid
));
1692 displaced_step_clear (displaced
);
1694 old_cleanups
= save_inferior_ptid ();
1695 inferior_ptid
= ptid
;
1697 original
= regcache_read_pc (regcache
);
1699 copy
= gdbarch_displaced_step_location (gdbarch
);
1700 len
= gdbarch_max_insn_length (gdbarch
);
1702 /* Save the original contents of the copy area. */
1703 displaced
->step_saved_copy
= xmalloc (len
);
1704 ignore_cleanups
= make_cleanup (free_current_contents
,
1705 &displaced
->step_saved_copy
);
1706 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1708 throw_error (MEMORY_ERROR
,
1709 _("Error accessing memory address %s (%s) for "
1710 "displaced-stepping scratch space."),
1711 paddress (gdbarch
, copy
), safe_strerror (status
));
1712 if (debug_displaced
)
1714 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1715 paddress (gdbarch
, copy
));
1716 displaced_step_dump_bytes (gdb_stdlog
,
1717 displaced
->step_saved_copy
,
1721 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1722 original
, copy
, regcache
);
1724 /* We don't support the fully-simulated case at present. */
1725 gdb_assert (closure
);
1727 /* Save the information we need to fix things up if the step
1729 displaced
->step_ptid
= ptid
;
1730 displaced
->step_gdbarch
= gdbarch
;
1731 displaced
->step_closure
= closure
;
1732 displaced
->step_original
= original
;
1733 displaced
->step_copy
= copy
;
1735 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1737 /* Resume execution at the copy. */
1738 regcache_write_pc (regcache
, copy
);
1740 discard_cleanups (ignore_cleanups
);
1742 do_cleanups (old_cleanups
);
1744 if (debug_displaced
)
1745 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1746 paddress (gdbarch
, copy
));
1752 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1753 const gdb_byte
*myaddr
, int len
)
1755 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1757 inferior_ptid
= ptid
;
1758 write_memory (memaddr
, myaddr
, len
);
1759 do_cleanups (ptid_cleanup
);
1762 /* Restore the contents of the copy area for thread PTID. */
1765 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1768 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1770 write_memory_ptid (ptid
, displaced
->step_copy
,
1771 displaced
->step_saved_copy
, len
);
1772 if (debug_displaced
)
1773 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1774 target_pid_to_str (ptid
),
1775 paddress (displaced
->step_gdbarch
,
1776 displaced
->step_copy
));
1780 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1782 struct cleanup
*old_cleanups
;
1783 struct displaced_step_inferior_state
*displaced
1784 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1786 /* Was any thread of this process doing a displaced step? */
1787 if (displaced
== NULL
)
1790 /* Was this event for the pid we displaced? */
1791 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1792 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1795 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1797 displaced_step_restore (displaced
, displaced
->step_ptid
);
1799 /* Did the instruction complete successfully? */
1800 if (signal
== GDB_SIGNAL_TRAP
)
1802 /* Fixup may need to read memory/registers. Switch to the
1803 thread that we're fixing up. */
1804 switch_to_thread (event_ptid
);
1806 /* Fix up the resulting state. */
1807 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1808 displaced
->step_closure
,
1809 displaced
->step_original
,
1810 displaced
->step_copy
,
1811 get_thread_regcache (displaced
->step_ptid
));
1815 /* Since the instruction didn't complete, all we can do is
1817 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1818 CORE_ADDR pc
= regcache_read_pc (regcache
);
1820 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1821 regcache_write_pc (regcache
, pc
);
1824 do_cleanups (old_cleanups
);
1826 displaced
->step_ptid
= null_ptid
;
1828 /* Are there any pending displaced stepping requests? If so, run
1829 one now. Leave the state object around, since we're likely to
1830 need it again soon. */
1831 while (displaced
->step_request_queue
)
1833 struct displaced_step_request
*head
;
1835 struct regcache
*regcache
;
1836 struct gdbarch
*gdbarch
;
1837 CORE_ADDR actual_pc
;
1838 struct address_space
*aspace
;
1840 head
= displaced
->step_request_queue
;
1842 displaced
->step_request_queue
= head
->next
;
1845 context_switch (ptid
);
1847 regcache
= get_thread_regcache (ptid
);
1848 actual_pc
= regcache_read_pc (regcache
);
1849 aspace
= get_regcache_aspace (regcache
);
1851 if (breakpoint_here_p (aspace
, actual_pc
))
1853 if (debug_displaced
)
1854 fprintf_unfiltered (gdb_stdlog
,
1855 "displaced: stepping queued %s now\n",
1856 target_pid_to_str (ptid
));
1858 displaced_step_prepare (ptid
);
1860 gdbarch
= get_regcache_arch (regcache
);
1862 if (debug_displaced
)
1864 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1867 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1868 paddress (gdbarch
, actual_pc
));
1869 read_memory (actual_pc
, buf
, sizeof (buf
));
1870 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1873 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1874 displaced
->step_closure
))
1875 target_resume (ptid
, 1, GDB_SIGNAL_0
);
1877 target_resume (ptid
, 0, GDB_SIGNAL_0
);
1879 /* Done, we're stepping a thread. */
1885 struct thread_info
*tp
= inferior_thread ();
1887 /* The breakpoint we were sitting under has since been
1889 tp
->control
.trap_expected
= 0;
1891 /* Go back to what we were trying to do. */
1892 step
= currently_stepping (tp
);
1894 if (debug_displaced
)
1895 fprintf_unfiltered (gdb_stdlog
,
1896 "displaced: breakpoint is gone: %s, step(%d)\n",
1897 target_pid_to_str (tp
->ptid
), step
);
1899 target_resume (ptid
, step
, GDB_SIGNAL_0
);
1900 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1902 /* This request was discarded. See if there's any other
1903 thread waiting for its turn. */
1908 /* Update global variables holding ptids to hold NEW_PTID if they were
1909 holding OLD_PTID. */
1911 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1913 struct displaced_step_request
*it
;
1914 struct displaced_step_inferior_state
*displaced
;
1916 if (ptid_equal (inferior_ptid
, old_ptid
))
1917 inferior_ptid
= new_ptid
;
1919 for (displaced
= displaced_step_inferior_states
;
1921 displaced
= displaced
->next
)
1923 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1924 displaced
->step_ptid
= new_ptid
;
1926 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1927 if (ptid_equal (it
->ptid
, old_ptid
))
1928 it
->ptid
= new_ptid
;
1935 /* Things to clean up if we QUIT out of resume (). */
1937 resume_cleanups (void *ignore
)
1939 if (!ptid_equal (inferior_ptid
, null_ptid
))
1940 delete_single_step_breakpoints (inferior_thread ());
1945 static const char schedlock_off
[] = "off";
1946 static const char schedlock_on
[] = "on";
1947 static const char schedlock_step
[] = "step";
1948 static const char *const scheduler_enums
[] = {
1954 static const char *scheduler_mode
= schedlock_off
;
1956 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1957 struct cmd_list_element
*c
, const char *value
)
1959 fprintf_filtered (file
,
1960 _("Mode for locking scheduler "
1961 "during execution is \"%s\".\n"),
1966 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1968 if (!target_can_lock_scheduler
)
1970 scheduler_mode
= schedlock_off
;
1971 error (_("Target '%s' cannot support this command."), target_shortname
);
1975 /* True if execution commands resume all threads of all processes by
1976 default; otherwise, resume only threads of the current inferior
1978 int sched_multi
= 0;
1980 /* Try to setup for software single stepping over the specified location.
1981 Return 1 if target_resume() should use hardware single step.
1983 GDBARCH the current gdbarch.
1984 PC the location to step over. */
1987 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1991 if (execution_direction
== EXEC_FORWARD
1992 && gdbarch_software_single_step_p (gdbarch
)
1993 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
2001 user_visible_resume_ptid (int step
)
2003 /* By default, resume all threads of all processes. */
2004 ptid_t resume_ptid
= RESUME_ALL
;
2006 /* Maybe resume only all threads of the current process. */
2007 if (!sched_multi
&& target_supports_multi_process ())
2009 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2012 /* Maybe resume a single thread after all. */
2015 /* With non-stop mode on, threads are always handled
2017 resume_ptid
= inferior_ptid
;
2019 else if ((scheduler_mode
== schedlock_on
)
2020 || (scheduler_mode
== schedlock_step
&& step
))
2022 /* User-settable 'scheduler' mode requires solo thread resume. */
2023 resume_ptid
= inferior_ptid
;
2026 /* We may actually resume fewer threads at first, e.g., if a thread
2027 is stopped at a breakpoint that needs stepping-off, but that
2028 should not be visible to the user/frontend, and neither should
2029 the frontend/user be allowed to proceed any of the threads that
2030 happen to be stopped for internal run control handling, if a
2031 previous command wanted them resumed. */
2035 /* Resume the inferior, but allow a QUIT. This is useful if the user
2036 wants to interrupt some lengthy single-stepping operation
2037 (for child processes, the SIGINT goes to the inferior, and so
2038 we get a SIGINT random_signal, but for remote debugging and perhaps
2039 other targets, that's not true).
2041 SIG is the signal to give the inferior (zero for none). */
2043 resume (int step
, enum gdb_signal sig
)
2045 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2046 struct regcache
*regcache
= get_current_regcache ();
2047 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2048 struct thread_info
*tp
= inferior_thread ();
2049 CORE_ADDR pc
= regcache_read_pc (regcache
);
2050 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2052 /* This represents the user's step vs continue request. When
2053 deciding whether "set scheduler-locking step" applies, it's the
2054 user's intention that counts. */
2055 const int user_step
= tp
->control
.stepping_command
;
2057 tp
->stepped_breakpoint
= 0;
2061 if (current_inferior ()->waiting_for_vfork_done
)
2063 /* Don't try to single-step a vfork parent that is waiting for
2064 the child to get out of the shared memory region (by exec'ing
2065 or exiting). This is particularly important on software
2066 single-step archs, as the child process would trip on the
2067 software single step breakpoint inserted for the parent
2068 process. Since the parent will not actually execute any
2069 instruction until the child is out of the shared region (such
2070 are vfork's semantics), it is safe to simply continue it.
2071 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2072 the parent, and tell it to `keep_going', which automatically
2073 re-sets it stepping. */
2075 fprintf_unfiltered (gdb_stdlog
,
2076 "infrun: resume : clear step\n");
2081 fprintf_unfiltered (gdb_stdlog
,
2082 "infrun: resume (step=%d, signal=%s), "
2083 "trap_expected=%d, current thread [%s] at %s\n",
2084 step
, gdb_signal_to_symbol_string (sig
),
2085 tp
->control
.trap_expected
,
2086 target_pid_to_str (inferior_ptid
),
2087 paddress (gdbarch
, pc
));
2089 /* Normally, by the time we reach `resume', the breakpoints are either
2090 removed or inserted, as appropriate. The exception is if we're sitting
2091 at a permanent breakpoint; we need to step over it, but permanent
2092 breakpoints can't be removed. So we have to test for it here. */
2093 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2095 if (sig
!= GDB_SIGNAL_0
)
2097 /* We have a signal to pass to the inferior. The resume
2098 may, or may not take us to the signal handler. If this
2099 is a step, we'll need to stop in the signal handler, if
2100 there's one, (if the target supports stepping into
2101 handlers), or in the next mainline instruction, if
2102 there's no handler. If this is a continue, we need to be
2103 sure to run the handler with all breakpoints inserted.
2104 In all cases, set a breakpoint at the current address
2105 (where the handler returns to), and once that breakpoint
2106 is hit, resume skipping the permanent breakpoint. If
2107 that breakpoint isn't hit, then we've stepped into the
2108 signal handler (or hit some other event). We'll delete
2109 the step-resume breakpoint then. */
2112 fprintf_unfiltered (gdb_stdlog
,
2113 "infrun: resume: skipping permanent breakpoint, "
2114 "deliver signal first\n");
2116 clear_step_over_info ();
2117 tp
->control
.trap_expected
= 0;
2119 if (tp
->control
.step_resume_breakpoint
== NULL
)
2121 /* Set a "high-priority" step-resume, as we don't want
2122 user breakpoints at PC to trigger (again) when this
2124 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2125 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2127 tp
->step_after_step_resume_breakpoint
= step
;
2130 insert_breakpoints ();
2134 /* There's no signal to pass, we can go ahead and skip the
2135 permanent breakpoint manually. */
2137 fprintf_unfiltered (gdb_stdlog
,
2138 "infrun: resume: skipping permanent breakpoint\n");
2139 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2140 /* Update pc to reflect the new address from which we will
2141 execute instructions. */
2142 pc
= regcache_read_pc (regcache
);
2146 /* We've already advanced the PC, so the stepping part
2147 is done. Now we need to arrange for a trap to be
2148 reported to handle_inferior_event. Set a breakpoint
2149 at the current PC, and run to it. Don't update
2150 prev_pc, because if we end in
2151 switch_back_to_stepping, we want the "expected thread
2152 advanced also" branch to be taken. IOW, we don't
2153 want this thread to step further from PC
2155 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2156 insert_breakpoints ();
2158 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2159 /* We're continuing with all breakpoints inserted. It's
2160 safe to let the target bypass signals. */
2161 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2162 /* ... and safe to let other threads run, according to
2164 resume_ptid
= user_visible_resume_ptid (user_step
);
2165 target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2166 discard_cleanups (old_cleanups
);
2172 /* If we have a breakpoint to step over, make sure to do a single
2173 step only. Same if we have software watchpoints. */
2174 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2175 tp
->control
.may_range_step
= 0;
2177 /* If enabled, step over breakpoints by executing a copy of the
2178 instruction at a different address.
2180 We can't use displaced stepping when we have a signal to deliver;
2181 the comments for displaced_step_prepare explain why. The
2182 comments in the handle_inferior event for dealing with 'random
2183 signals' explain what we do instead.
2185 We can't use displaced stepping when we are waiting for vfork_done
2186 event, displaced stepping breaks the vfork child similarly as single
2187 step software breakpoint. */
2188 if (use_displaced_stepping (gdbarch
)
2189 && tp
->control
.trap_expected
2190 && sig
== GDB_SIGNAL_0
2191 && !current_inferior ()->waiting_for_vfork_done
)
2193 struct displaced_step_inferior_state
*displaced
;
2195 if (!displaced_step_prepare (inferior_ptid
))
2197 /* Got placed in displaced stepping queue. Will be resumed
2198 later when all the currently queued displaced stepping
2199 requests finish. The thread is not executing at this
2200 point, and the call to set_executing will be made later.
2201 But we need to call set_running here, since from the
2202 user/frontend's point of view, threads were set running.
2203 Unless we're calling an inferior function, as in that
2204 case we pretend the inferior doesn't run at all. */
2205 if (!tp
->control
.in_infcall
)
2206 set_running (user_visible_resume_ptid (user_step
), 1);
2207 discard_cleanups (old_cleanups
);
2211 /* Update pc to reflect the new address from which we will execute
2212 instructions due to displaced stepping. */
2213 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2215 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2216 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2217 displaced
->step_closure
);
2220 /* Do we need to do it the hard way, w/temp breakpoints? */
2222 step
= maybe_software_singlestep (gdbarch
, pc
);
2224 /* Currently, our software single-step implementation leads to different
2225 results than hardware single-stepping in one situation: when stepping
2226 into delivering a signal which has an associated signal handler,
2227 hardware single-step will stop at the first instruction of the handler,
2228 while software single-step will simply skip execution of the handler.
2230 For now, this difference in behavior is accepted since there is no
2231 easy way to actually implement single-stepping into a signal handler
2232 without kernel support.
2234 However, there is one scenario where this difference leads to follow-on
2235 problems: if we're stepping off a breakpoint by removing all breakpoints
2236 and then single-stepping. In this case, the software single-step
2237 behavior means that even if there is a *breakpoint* in the signal
2238 handler, GDB still would not stop.
2240 Fortunately, we can at least fix this particular issue. We detect
2241 here the case where we are about to deliver a signal while software
2242 single-stepping with breakpoints removed. In this situation, we
2243 revert the decisions to remove all breakpoints and insert single-
2244 step breakpoints, and instead we install a step-resume breakpoint
2245 at the current address, deliver the signal without stepping, and
2246 once we arrive back at the step-resume breakpoint, actually step
2247 over the breakpoint we originally wanted to step over. */
2248 if (thread_has_single_step_breakpoints_set (tp
)
2249 && sig
!= GDB_SIGNAL_0
2250 && step_over_info_valid_p ())
2252 /* If we have nested signals or a pending signal is delivered
2253 immediately after a handler returns, might might already have
2254 a step-resume breakpoint set on the earlier handler. We cannot
2255 set another step-resume breakpoint; just continue on until the
2256 original breakpoint is hit. */
2257 if (tp
->control
.step_resume_breakpoint
== NULL
)
2259 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2260 tp
->step_after_step_resume_breakpoint
= 1;
2263 delete_single_step_breakpoints (tp
);
2265 clear_step_over_info ();
2266 tp
->control
.trap_expected
= 0;
2268 insert_breakpoints ();
2271 /* If STEP is set, it's a request to use hardware stepping
2272 facilities. But in that case, we should never
2273 use singlestep breakpoint. */
2274 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2276 /* Decide the set of threads to ask the target to resume. Start
2277 by assuming everything will be resumed, than narrow the set
2278 by applying increasingly restricting conditions. */
2279 resume_ptid
= user_visible_resume_ptid (user_step
);
2281 /* Even if RESUME_PTID is a wildcard, and we end up resuming less
2282 (e.g., we might need to step over a breakpoint), from the
2283 user/frontend's point of view, all threads in RESUME_PTID are now
2284 running. Unless we're calling an inferior function, as in that
2285 case pretend we inferior doesn't run at all. */
2286 if (!tp
->control
.in_infcall
)
2287 set_running (resume_ptid
, 1);
2289 /* Maybe resume a single thread after all. */
2290 if ((step
|| thread_has_single_step_breakpoints_set (tp
))
2291 && tp
->control
.trap_expected
)
2293 /* We're allowing a thread to run past a breakpoint it has
2294 hit, by single-stepping the thread with the breakpoint
2295 removed. In which case, we need to single-step only this
2296 thread, and keep others stopped, as they can miss this
2297 breakpoint if allowed to run. */
2298 resume_ptid
= inferior_ptid
;
2301 if (execution_direction
!= EXEC_REVERSE
2302 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2304 /* The only case we currently need to step a breakpoint
2305 instruction is when we have a signal to deliver. See
2306 handle_signal_stop where we handle random signals that could
2307 take out us out of the stepping range. Normally, in that
2308 case we end up continuing (instead of stepping) over the
2309 signal handler with a breakpoint at PC, but there are cases
2310 where we should _always_ single-step, even if we have a
2311 step-resume breakpoint, like when a software watchpoint is
2312 set. Assuming single-stepping and delivering a signal at the
2313 same time would takes us to the signal handler, then we could
2314 have removed the breakpoint at PC to step over it. However,
2315 some hardware step targets (like e.g., Mac OS) can't step
2316 into signal handlers, and for those, we need to leave the
2317 breakpoint at PC inserted, as otherwise if the handler
2318 recurses and executes PC again, it'll miss the breakpoint.
2319 So we leave the breakpoint inserted anyway, but we need to
2320 record that we tried to step a breakpoint instruction, so
2321 that adjust_pc_after_break doesn't end up confused. */
2322 gdb_assert (sig
!= GDB_SIGNAL_0
);
2324 tp
->stepped_breakpoint
= 1;
2326 /* Most targets can step a breakpoint instruction, thus
2327 executing it normally. But if this one cannot, just
2328 continue and we will hit it anyway. */
2329 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2334 && use_displaced_stepping (gdbarch
)
2335 && tp
->control
.trap_expected
)
2337 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
2338 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2339 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2342 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2343 paddress (resume_gdbarch
, actual_pc
));
2344 read_memory (actual_pc
, buf
, sizeof (buf
));
2345 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2348 if (tp
->control
.may_range_step
)
2350 /* If we're resuming a thread with the PC out of the step
2351 range, then we're doing some nested/finer run control
2352 operation, like stepping the thread out of the dynamic
2353 linker or the displaced stepping scratch pad. We
2354 shouldn't have allowed a range step then. */
2355 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2358 /* Install inferior's terminal modes. */
2359 target_terminal_inferior ();
2361 /* Avoid confusing the next resume, if the next stop/resume
2362 happens to apply to another thread. */
2363 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2365 /* Advise target which signals may be handled silently. If we have
2366 removed breakpoints because we are stepping over one (in any
2367 thread), we need to receive all signals to avoid accidentally
2368 skipping a breakpoint during execution of a signal handler. */
2369 if (step_over_info_valid_p ())
2370 target_pass_signals (0, NULL
);
2372 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2374 target_resume (resume_ptid
, step
, sig
);
2376 discard_cleanups (old_cleanups
);
2381 /* Clear out all variables saying what to do when inferior is continued.
2382 First do this, then set the ones you want, then call `proceed'. */
2385 clear_proceed_status_thread (struct thread_info
*tp
)
2388 fprintf_unfiltered (gdb_stdlog
,
2389 "infrun: clear_proceed_status_thread (%s)\n",
2390 target_pid_to_str (tp
->ptid
));
2392 /* If this signal should not be seen by program, give it zero.
2393 Used for debugging signals. */
2394 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2395 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2397 tp
->control
.trap_expected
= 0;
2398 tp
->control
.step_range_start
= 0;
2399 tp
->control
.step_range_end
= 0;
2400 tp
->control
.may_range_step
= 0;
2401 tp
->control
.step_frame_id
= null_frame_id
;
2402 tp
->control
.step_stack_frame_id
= null_frame_id
;
2403 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2404 tp
->control
.step_start_function
= NULL
;
2405 tp
->stop_requested
= 0;
2407 tp
->control
.stop_step
= 0;
2409 tp
->control
.proceed_to_finish
= 0;
2411 tp
->control
.command_interp
= NULL
;
2412 tp
->control
.stepping_command
= 0;
2414 /* Discard any remaining commands or status from previous stop. */
2415 bpstat_clear (&tp
->control
.stop_bpstat
);
2419 clear_proceed_status (int step
)
2423 struct thread_info
*tp
;
2426 resume_ptid
= user_visible_resume_ptid (step
);
2428 /* In all-stop mode, delete the per-thread status of all threads
2429 we're about to resume, implicitly and explicitly. */
2430 ALL_NON_EXITED_THREADS (tp
)
2432 if (!ptid_match (tp
->ptid
, resume_ptid
))
2434 clear_proceed_status_thread (tp
);
2438 if (!ptid_equal (inferior_ptid
, null_ptid
))
2440 struct inferior
*inferior
;
2444 /* If in non-stop mode, only delete the per-thread status of
2445 the current thread. */
2446 clear_proceed_status_thread (inferior_thread ());
2449 inferior
= current_inferior ();
2450 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2453 stop_after_trap
= 0;
2455 clear_step_over_info ();
2457 observer_notify_about_to_proceed ();
2461 regcache_xfree (stop_registers
);
2462 stop_registers
= NULL
;
2466 /* Returns true if TP is still stopped at a breakpoint that needs
2467 stepping-over in order to make progress. If the breakpoint is gone
2468 meanwhile, we can skip the whole step-over dance. */
2471 thread_still_needs_step_over (struct thread_info
*tp
)
2473 if (tp
->stepping_over_breakpoint
)
2475 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2477 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2478 regcache_read_pc (regcache
))
2479 == ordinary_breakpoint_here
)
2482 tp
->stepping_over_breakpoint
= 0;
2488 /* Returns true if scheduler locking applies. STEP indicates whether
2489 we're about to do a step/next-like command to a thread. */
2492 schedlock_applies (struct thread_info
*tp
)
2494 return (scheduler_mode
== schedlock_on
2495 || (scheduler_mode
== schedlock_step
2496 && tp
->control
.stepping_command
));
2499 /* Look a thread other than EXCEPT that has previously reported a
2500 breakpoint event, and thus needs a step-over in order to make
2501 progress. Returns NULL is none is found. */
2503 static struct thread_info
*
2504 find_thread_needs_step_over (struct thread_info
*except
)
2506 struct thread_info
*tp
, *current
;
2508 /* With non-stop mode on, threads are always handled individually. */
2509 gdb_assert (! non_stop
);
2511 current
= inferior_thread ();
2513 /* If scheduler locking applies, we can avoid iterating over all
2515 if (schedlock_applies (except
))
2517 if (except
!= current
2518 && thread_still_needs_step_over (current
))
2524 ALL_NON_EXITED_THREADS (tp
)
2526 /* Ignore the EXCEPT thread. */
2529 /* Ignore threads of processes we're not resuming. */
2531 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
2534 if (thread_still_needs_step_over (tp
))
2541 /* Basic routine for continuing the program in various fashions.
2543 ADDR is the address to resume at, or -1 for resume where stopped.
2544 SIGGNAL is the signal to give it, or 0 for none,
2545 or -1 for act according to how it stopped.
2546 STEP is nonzero if should trap after one instruction.
2547 -1 means return after that and print nothing.
2548 You should probably set various step_... variables
2549 before calling here, if you are stepping.
2551 You should call clear_proceed_status before calling proceed. */
2554 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
, int step
)
2556 struct regcache
*regcache
;
2557 struct gdbarch
*gdbarch
;
2558 struct thread_info
*tp
;
2560 struct address_space
*aspace
;
2562 /* If we're stopped at a fork/vfork, follow the branch set by the
2563 "set follow-fork-mode" command; otherwise, we'll just proceed
2564 resuming the current thread. */
2565 if (!follow_fork ())
2567 /* The target for some reason decided not to resume. */
2569 if (target_can_async_p ())
2570 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2574 /* We'll update this if & when we switch to a new thread. */
2575 previous_inferior_ptid
= inferior_ptid
;
2577 regcache
= get_current_regcache ();
2578 gdbarch
= get_regcache_arch (regcache
);
2579 aspace
= get_regcache_aspace (regcache
);
2580 pc
= regcache_read_pc (regcache
);
2581 tp
= inferior_thread ();
2584 tp
->control
.step_start_function
= find_pc_function (pc
);
2586 /* Fill in with reasonable starting values. */
2587 init_thread_stepping_state (tp
);
2589 if (addr
== (CORE_ADDR
) -1)
2592 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
2593 && execution_direction
!= EXEC_REVERSE
)
2594 /* There is a breakpoint at the address we will resume at,
2595 step one instruction before inserting breakpoints so that
2596 we do not stop right away (and report a second hit at this
2599 Note, we don't do this in reverse, because we won't
2600 actually be executing the breakpoint insn anyway.
2601 We'll be (un-)executing the previous instruction. */
2602 tp
->stepping_over_breakpoint
= 1;
2603 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2604 && gdbarch_single_step_through_delay (gdbarch
,
2605 get_current_frame ()))
2606 /* We stepped onto an instruction that needs to be stepped
2607 again before re-inserting the breakpoint, do so. */
2608 tp
->stepping_over_breakpoint
= 1;
2612 regcache_write_pc (regcache
, addr
);
2615 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2616 tp
->suspend
.stop_signal
= siggnal
;
2618 /* Record the interpreter that issued the execution command that
2619 caused this thread to resume. If the top level interpreter is
2620 MI/async, and the execution command was a CLI command
2621 (next/step/etc.), we'll want to print stop event output to the MI
2622 console channel (the stepped-to line, etc.), as if the user
2623 entered the execution command on a real GDB console. */
2624 inferior_thread ()->control
.command_interp
= command_interp ();
2627 fprintf_unfiltered (gdb_stdlog
,
2628 "infrun: proceed (addr=%s, signal=%s, step=%d)\n",
2629 paddress (gdbarch
, addr
),
2630 gdb_signal_to_symbol_string (siggnal
), step
);
2633 /* In non-stop, each thread is handled individually. The context
2634 must already be set to the right thread here. */
2638 struct thread_info
*step_over
;
2640 /* In a multi-threaded task we may select another thread and
2641 then continue or step.
2643 But if the old thread was stopped at a breakpoint, it will
2644 immediately cause another breakpoint stop without any
2645 execution (i.e. it will report a breakpoint hit incorrectly).
2646 So we must step over it first.
2648 Look for a thread other than the current (TP) that reported a
2649 breakpoint hit and hasn't been resumed yet since. */
2650 step_over
= find_thread_needs_step_over (tp
);
2651 if (step_over
!= NULL
)
2654 fprintf_unfiltered (gdb_stdlog
,
2655 "infrun: need to step-over [%s] first\n",
2656 target_pid_to_str (step_over
->ptid
));
2658 /* Store the prev_pc for the stepping thread too, needed by
2659 switch_back_to_stepping thread. */
2660 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2661 switch_to_thread (step_over
->ptid
);
2666 /* If we need to step over a breakpoint, and we're not using
2667 displaced stepping to do so, insert all breakpoints (watchpoints,
2668 etc.) but the one we're stepping over, step one instruction, and
2669 then re-insert the breakpoint when that step is finished. */
2670 if (tp
->stepping_over_breakpoint
&& !use_displaced_stepping (gdbarch
))
2672 struct regcache
*regcache
= get_current_regcache ();
2674 set_step_over_info (get_regcache_aspace (regcache
),
2675 regcache_read_pc (regcache
), 0);
2678 clear_step_over_info ();
2680 insert_breakpoints ();
2682 tp
->control
.trap_expected
= tp
->stepping_over_breakpoint
;
2684 annotate_starting ();
2686 /* Make sure that output from GDB appears before output from the
2688 gdb_flush (gdb_stdout
);
2690 /* Refresh prev_pc value just prior to resuming. This used to be
2691 done in stop_waiting, however, setting prev_pc there did not handle
2692 scenarios such as inferior function calls or returning from
2693 a function via the return command. In those cases, the prev_pc
2694 value was not set properly for subsequent commands. The prev_pc value
2695 is used to initialize the starting line number in the ecs. With an
2696 invalid value, the gdb next command ends up stopping at the position
2697 represented by the next line table entry past our start position.
2698 On platforms that generate one line table entry per line, this
2699 is not a problem. However, on the ia64, the compiler generates
2700 extraneous line table entries that do not increase the line number.
2701 When we issue the gdb next command on the ia64 after an inferior call
2702 or a return command, we often end up a few instructions forward, still
2703 within the original line we started.
2705 An attempt was made to refresh the prev_pc at the same time the
2706 execution_control_state is initialized (for instance, just before
2707 waiting for an inferior event). But this approach did not work
2708 because of platforms that use ptrace, where the pc register cannot
2709 be read unless the inferior is stopped. At that point, we are not
2710 guaranteed the inferior is stopped and so the regcache_read_pc() call
2711 can fail. Setting the prev_pc value here ensures the value is updated
2712 correctly when the inferior is stopped. */
2713 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2715 /* Resume inferior. */
2716 resume (tp
->control
.trap_expected
|| step
|| bpstat_should_step (),
2717 tp
->suspend
.stop_signal
);
2719 /* Wait for it to stop (if not standalone)
2720 and in any case decode why it stopped, and act accordingly. */
2721 /* Do this only if we are not using the event loop, or if the target
2722 does not support asynchronous execution. */
2723 if (!target_can_async_p ())
2725 wait_for_inferior ();
2731 /* Start remote-debugging of a machine over a serial link. */
2734 start_remote (int from_tty
)
2736 struct inferior
*inferior
;
2738 inferior
= current_inferior ();
2739 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2741 /* Always go on waiting for the target, regardless of the mode. */
2742 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2743 indicate to wait_for_inferior that a target should timeout if
2744 nothing is returned (instead of just blocking). Because of this,
2745 targets expecting an immediate response need to, internally, set
2746 things up so that the target_wait() is forced to eventually
2748 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2749 differentiate to its caller what the state of the target is after
2750 the initial open has been performed. Here we're assuming that
2751 the target has stopped. It should be possible to eventually have
2752 target_open() return to the caller an indication that the target
2753 is currently running and GDB state should be set to the same as
2754 for an async run. */
2755 wait_for_inferior ();
2757 /* Now that the inferior has stopped, do any bookkeeping like
2758 loading shared libraries. We want to do this before normal_stop,
2759 so that the displayed frame is up to date. */
2760 post_create_inferior (¤t_target
, from_tty
);
2765 /* Initialize static vars when a new inferior begins. */
2768 init_wait_for_inferior (void)
2770 /* These are meaningless until the first time through wait_for_inferior. */
2772 breakpoint_init_inferior (inf_starting
);
2774 clear_proceed_status (0);
2776 target_last_wait_ptid
= minus_one_ptid
;
2778 previous_inferior_ptid
= inferior_ptid
;
2780 /* Discard any skipped inlined frames. */
2781 clear_inline_frame_state (minus_one_ptid
);
2785 /* Data to be passed around while handling an event. This data is
2786 discarded between events. */
2787 struct execution_control_state
2790 /* The thread that got the event, if this was a thread event; NULL
2792 struct thread_info
*event_thread
;
2794 struct target_waitstatus ws
;
2795 int stop_func_filled_in
;
2796 CORE_ADDR stop_func_start
;
2797 CORE_ADDR stop_func_end
;
2798 const char *stop_func_name
;
2801 /* True if the event thread hit the single-step breakpoint of
2802 another thread. Thus the event doesn't cause a stop, the thread
2803 needs to be single-stepped past the single-step breakpoint before
2804 we can switch back to the original stepping thread. */
2805 int hit_singlestep_breakpoint
;
2808 static void handle_inferior_event (struct execution_control_state
*ecs
);
2810 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2811 struct execution_control_state
*ecs
);
2812 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2813 struct execution_control_state
*ecs
);
2814 static void handle_signal_stop (struct execution_control_state
*ecs
);
2815 static void check_exception_resume (struct execution_control_state
*,
2816 struct frame_info
*);
2818 static void end_stepping_range (struct execution_control_state
*ecs
);
2819 static void stop_waiting (struct execution_control_state
*ecs
);
2820 static void prepare_to_wait (struct execution_control_state
*ecs
);
2821 static void keep_going (struct execution_control_state
*ecs
);
2822 static void process_event_stop_test (struct execution_control_state
*ecs
);
2823 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
2825 /* Callback for iterate over threads. If the thread is stopped, but
2826 the user/frontend doesn't know about that yet, go through
2827 normal_stop, as if the thread had just stopped now. ARG points at
2828 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2829 ptid_is_pid(PTID) is true, applies to all threads of the process
2830 pointed at by PTID. Otherwise, apply only to the thread pointed by
2834 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2836 ptid_t ptid
= * (ptid_t
*) arg
;
2838 if ((ptid_equal (info
->ptid
, ptid
)
2839 || ptid_equal (minus_one_ptid
, ptid
)
2840 || (ptid_is_pid (ptid
)
2841 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2842 && is_running (info
->ptid
)
2843 && !is_executing (info
->ptid
))
2845 struct cleanup
*old_chain
;
2846 struct execution_control_state ecss
;
2847 struct execution_control_state
*ecs
= &ecss
;
2849 memset (ecs
, 0, sizeof (*ecs
));
2851 old_chain
= make_cleanup_restore_current_thread ();
2853 overlay_cache_invalid
= 1;
2854 /* Flush target cache before starting to handle each event.
2855 Target was running and cache could be stale. This is just a
2856 heuristic. Running threads may modify target memory, but we
2857 don't get any event. */
2858 target_dcache_invalidate ();
2860 /* Go through handle_inferior_event/normal_stop, so we always
2861 have consistent output as if the stop event had been
2863 ecs
->ptid
= info
->ptid
;
2864 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2865 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2866 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2868 handle_inferior_event (ecs
);
2870 if (!ecs
->wait_some_more
)
2872 struct thread_info
*tp
;
2876 /* Finish off the continuations. */
2877 tp
= inferior_thread ();
2878 do_all_intermediate_continuations_thread (tp
, 1);
2879 do_all_continuations_thread (tp
, 1);
2882 do_cleanups (old_chain
);
2888 /* This function is attached as a "thread_stop_requested" observer.
2889 Cleanup local state that assumed the PTID was to be resumed, and
2890 report the stop to the frontend. */
2893 infrun_thread_stop_requested (ptid_t ptid
)
2895 struct displaced_step_inferior_state
*displaced
;
2897 /* PTID was requested to stop. Remove it from the displaced
2898 stepping queue, so we don't try to resume it automatically. */
2900 for (displaced
= displaced_step_inferior_states
;
2902 displaced
= displaced
->next
)
2904 struct displaced_step_request
*it
, **prev_next_p
;
2906 it
= displaced
->step_request_queue
;
2907 prev_next_p
= &displaced
->step_request_queue
;
2910 if (ptid_match (it
->ptid
, ptid
))
2912 *prev_next_p
= it
->next
;
2918 prev_next_p
= &it
->next
;
2925 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2929 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2931 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2932 nullify_last_target_wait_ptid ();
2935 /* Delete the step resume, single-step and longjmp/exception resume
2936 breakpoints of TP. */
2939 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
2941 delete_step_resume_breakpoint (tp
);
2942 delete_exception_resume_breakpoint (tp
);
2943 delete_single_step_breakpoints (tp
);
2946 /* If the target still has execution, call FUNC for each thread that
2947 just stopped. In all-stop, that's all the non-exited threads; in
2948 non-stop, that's the current thread, only. */
2950 typedef void (*for_each_just_stopped_thread_callback_func
)
2951 (struct thread_info
*tp
);
2954 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
2956 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
2961 /* If in non-stop mode, only the current thread stopped. */
2962 func (inferior_thread ());
2966 struct thread_info
*tp
;
2968 /* In all-stop mode, all threads have stopped. */
2969 ALL_NON_EXITED_THREADS (tp
)
2976 /* Delete the step resume and longjmp/exception resume breakpoints of
2977 the threads that just stopped. */
2980 delete_just_stopped_threads_infrun_breakpoints (void)
2982 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
2985 /* Delete the single-step breakpoints of the threads that just
2989 delete_just_stopped_threads_single_step_breakpoints (void)
2991 for_each_just_stopped_thread (delete_single_step_breakpoints
);
2994 /* A cleanup wrapper. */
2997 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
2999 delete_just_stopped_threads_infrun_breakpoints ();
3002 /* Pretty print the results of target_wait, for debugging purposes. */
3005 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3006 const struct target_waitstatus
*ws
)
3008 char *status_string
= target_waitstatus_to_string (ws
);
3009 struct ui_file
*tmp_stream
= mem_fileopen ();
3012 /* The text is split over several lines because it was getting too long.
3013 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3014 output as a unit; we want only one timestamp printed if debug_timestamp
3017 fprintf_unfiltered (tmp_stream
,
3018 "infrun: target_wait (%d", ptid_get_pid (waiton_ptid
));
3019 if (ptid_get_pid (waiton_ptid
) != -1)
3020 fprintf_unfiltered (tmp_stream
,
3021 " [%s]", target_pid_to_str (waiton_ptid
));
3022 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3023 fprintf_unfiltered (tmp_stream
,
3024 "infrun: %d [%s],\n",
3025 ptid_get_pid (result_ptid
),
3026 target_pid_to_str (result_ptid
));
3027 fprintf_unfiltered (tmp_stream
,
3031 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3033 /* This uses %s in part to handle %'s in the text, but also to avoid
3034 a gcc error: the format attribute requires a string literal. */
3035 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3037 xfree (status_string
);
3039 ui_file_delete (tmp_stream
);
3042 /* Prepare and stabilize the inferior for detaching it. E.g.,
3043 detaching while a thread is displaced stepping is a recipe for
3044 crashing it, as nothing would readjust the PC out of the scratch
3048 prepare_for_detach (void)
3050 struct inferior
*inf
= current_inferior ();
3051 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3052 struct cleanup
*old_chain_1
;
3053 struct displaced_step_inferior_state
*displaced
;
3055 displaced
= get_displaced_stepping_state (inf
->pid
);
3057 /* Is any thread of this process displaced stepping? If not,
3058 there's nothing else to do. */
3059 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3063 fprintf_unfiltered (gdb_stdlog
,
3064 "displaced-stepping in-process while detaching");
3066 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3069 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3071 struct cleanup
*old_chain_2
;
3072 struct execution_control_state ecss
;
3073 struct execution_control_state
*ecs
;
3076 memset (ecs
, 0, sizeof (*ecs
));
3078 overlay_cache_invalid
= 1;
3079 /* Flush target cache before starting to handle each event.
3080 Target was running and cache could be stale. This is just a
3081 heuristic. Running threads may modify target memory, but we
3082 don't get any event. */
3083 target_dcache_invalidate ();
3085 if (deprecated_target_wait_hook
)
3086 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
3088 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
3091 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3093 /* If an error happens while handling the event, propagate GDB's
3094 knowledge of the executing state to the frontend/user running
3096 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3099 /* Now figure out what to do with the result of the result. */
3100 handle_inferior_event (ecs
);
3102 /* No error, don't finish the state yet. */
3103 discard_cleanups (old_chain_2
);
3105 /* Breakpoints and watchpoints are not installed on the target
3106 at this point, and signals are passed directly to the
3107 inferior, so this must mean the process is gone. */
3108 if (!ecs
->wait_some_more
)
3110 discard_cleanups (old_chain_1
);
3111 error (_("Program exited while detaching"));
3115 discard_cleanups (old_chain_1
);
3118 /* Wait for control to return from inferior to debugger.
3120 If inferior gets a signal, we may decide to start it up again
3121 instead of returning. That is why there is a loop in this function.
3122 When this function actually returns it means the inferior
3123 should be left stopped and GDB should read more commands. */
3126 wait_for_inferior (void)
3128 struct cleanup
*old_cleanups
;
3132 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3135 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3140 struct execution_control_state ecss
;
3141 struct execution_control_state
*ecs
= &ecss
;
3142 struct cleanup
*old_chain
;
3143 ptid_t waiton_ptid
= minus_one_ptid
;
3145 memset (ecs
, 0, sizeof (*ecs
));
3147 overlay_cache_invalid
= 1;
3149 /* Flush target cache before starting to handle each event.
3150 Target was running and cache could be stale. This is just a
3151 heuristic. Running threads may modify target memory, but we
3152 don't get any event. */
3153 target_dcache_invalidate ();
3155 if (deprecated_target_wait_hook
)
3156 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
3158 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
3161 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3163 /* If an error happens while handling the event, propagate GDB's
3164 knowledge of the executing state to the frontend/user running
3166 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3168 /* Now figure out what to do with the result of the result. */
3169 handle_inferior_event (ecs
);
3171 /* No error, don't finish the state yet. */
3172 discard_cleanups (old_chain
);
3174 if (!ecs
->wait_some_more
)
3178 do_cleanups (old_cleanups
);
3181 /* Cleanup that reinstalls the readline callback handler, if the
3182 target is running in the background. If while handling the target
3183 event something triggered a secondary prompt, like e.g., a
3184 pagination prompt, we'll have removed the callback handler (see
3185 gdb_readline_wrapper_line). Need to do this as we go back to the
3186 event loop, ready to process further input. Note this has no
3187 effect if the handler hasn't actually been removed, because calling
3188 rl_callback_handler_install resets the line buffer, thus losing
3192 reinstall_readline_callback_handler_cleanup (void *arg
)
3194 if (!interpreter_async
)
3196 /* We're not going back to the top level event loop yet. Don't
3197 install the readline callback, as it'd prep the terminal,
3198 readline-style (raw, noecho) (e.g., --batch). We'll install
3199 it the next time the prompt is displayed, when we're ready
3204 if (async_command_editing_p
&& !sync_execution
)
3205 gdb_rl_callback_handler_reinstall ();
3208 /* Asynchronous version of wait_for_inferior. It is called by the
3209 event loop whenever a change of state is detected on the file
3210 descriptor corresponding to the target. It can be called more than
3211 once to complete a single execution command. In such cases we need
3212 to keep the state in a global variable ECSS. If it is the last time
3213 that this function is called for a single execution command, then
3214 report to the user that the inferior has stopped, and do the
3215 necessary cleanups. */
3218 fetch_inferior_event (void *client_data
)
3220 struct execution_control_state ecss
;
3221 struct execution_control_state
*ecs
= &ecss
;
3222 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3223 struct cleanup
*ts_old_chain
;
3224 int was_sync
= sync_execution
;
3226 ptid_t waiton_ptid
= minus_one_ptid
;
3228 memset (ecs
, 0, sizeof (*ecs
));
3230 /* End up with readline processing input, if necessary. */
3231 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3233 /* We're handling a live event, so make sure we're doing live
3234 debugging. If we're looking at traceframes while the target is
3235 running, we're going to need to get back to that mode after
3236 handling the event. */
3239 make_cleanup_restore_current_traceframe ();
3240 set_current_traceframe (-1);
3244 /* In non-stop mode, the user/frontend should not notice a thread
3245 switch due to internal events. Make sure we reverse to the
3246 user selected thread and frame after handling the event and
3247 running any breakpoint commands. */
3248 make_cleanup_restore_current_thread ();
3250 overlay_cache_invalid
= 1;
3251 /* Flush target cache before starting to handle each event. Target
3252 was running and cache could be stale. This is just a heuristic.
3253 Running threads may modify target memory, but we don't get any
3255 target_dcache_invalidate ();
3257 make_cleanup_restore_integer (&execution_direction
);
3258 execution_direction
= target_execution_direction ();
3260 if (deprecated_target_wait_hook
)
3262 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3264 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3267 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3269 /* If an error happens while handling the event, propagate GDB's
3270 knowledge of the executing state to the frontend/user running
3273 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3275 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3277 /* Get executed before make_cleanup_restore_current_thread above to apply
3278 still for the thread which has thrown the exception. */
3279 make_bpstat_clear_actions_cleanup ();
3281 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3283 /* Now figure out what to do with the result of the result. */
3284 handle_inferior_event (ecs
);
3286 if (!ecs
->wait_some_more
)
3288 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3290 delete_just_stopped_threads_infrun_breakpoints ();
3292 /* We may not find an inferior if this was a process exit. */
3293 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3296 if (target_has_execution
3297 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
3298 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3299 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3300 && ecs
->event_thread
->step_multi
3301 && ecs
->event_thread
->control
.stop_step
)
3302 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
3305 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3310 /* No error, don't finish the thread states yet. */
3311 discard_cleanups (ts_old_chain
);
3313 /* Revert thread and frame. */
3314 do_cleanups (old_chain
);
3316 /* If the inferior was in sync execution mode, and now isn't,
3317 restore the prompt (a synchronous execution command has finished,
3318 and we're ready for input). */
3319 if (interpreter_async
&& was_sync
&& !sync_execution
)
3320 observer_notify_sync_execution_done ();
3324 && exec_done_display_p
3325 && (ptid_equal (inferior_ptid
, null_ptid
)
3326 || !is_running (inferior_ptid
)))
3327 printf_unfiltered (_("completed.\n"));
3330 /* Record the frame and location we're currently stepping through. */
3332 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3334 struct thread_info
*tp
= inferior_thread ();
3336 tp
->control
.step_frame_id
= get_frame_id (frame
);
3337 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3339 tp
->current_symtab
= sal
.symtab
;
3340 tp
->current_line
= sal
.line
;
3343 /* Clear context switchable stepping state. */
3346 init_thread_stepping_state (struct thread_info
*tss
)
3348 tss
->stepped_breakpoint
= 0;
3349 tss
->stepping_over_breakpoint
= 0;
3350 tss
->stepping_over_watchpoint
= 0;
3351 tss
->step_after_step_resume_breakpoint
= 0;
3354 /* Set the cached copy of the last ptid/waitstatus. */
3357 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3359 target_last_wait_ptid
= ptid
;
3360 target_last_waitstatus
= status
;
3363 /* Return the cached copy of the last pid/waitstatus returned by
3364 target_wait()/deprecated_target_wait_hook(). The data is actually
3365 cached by handle_inferior_event(), which gets called immediately
3366 after target_wait()/deprecated_target_wait_hook(). */
3369 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3371 *ptidp
= target_last_wait_ptid
;
3372 *status
= target_last_waitstatus
;
3376 nullify_last_target_wait_ptid (void)
3378 target_last_wait_ptid
= minus_one_ptid
;
3381 /* Switch thread contexts. */
3384 context_switch (ptid_t ptid
)
3386 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
3388 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3389 target_pid_to_str (inferior_ptid
));
3390 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3391 target_pid_to_str (ptid
));
3394 switch_to_thread (ptid
);
3398 adjust_pc_after_break (struct execution_control_state
*ecs
)
3400 struct regcache
*regcache
;
3401 struct gdbarch
*gdbarch
;
3402 struct address_space
*aspace
;
3403 CORE_ADDR breakpoint_pc
, decr_pc
;
3405 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3406 we aren't, just return.
3408 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3409 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3410 implemented by software breakpoints should be handled through the normal
3413 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3414 different signals (SIGILL or SIGEMT for instance), but it is less
3415 clear where the PC is pointing afterwards. It may not match
3416 gdbarch_decr_pc_after_break. I don't know any specific target that
3417 generates these signals at breakpoints (the code has been in GDB since at
3418 least 1992) so I can not guess how to handle them here.
3420 In earlier versions of GDB, a target with
3421 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3422 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3423 target with both of these set in GDB history, and it seems unlikely to be
3424 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3426 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
3429 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
3432 /* In reverse execution, when a breakpoint is hit, the instruction
3433 under it has already been de-executed. The reported PC always
3434 points at the breakpoint address, so adjusting it further would
3435 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3438 B1 0x08000000 : INSN1
3439 B2 0x08000001 : INSN2
3441 PC -> 0x08000003 : INSN4
3443 Say you're stopped at 0x08000003 as above. Reverse continuing
3444 from that point should hit B2 as below. Reading the PC when the
3445 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3446 been de-executed already.
3448 B1 0x08000000 : INSN1
3449 B2 PC -> 0x08000001 : INSN2
3453 We can't apply the same logic as for forward execution, because
3454 we would wrongly adjust the PC to 0x08000000, since there's a
3455 breakpoint at PC - 1. We'd then report a hit on B1, although
3456 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3458 if (execution_direction
== EXEC_REVERSE
)
3461 /* If the target can tell whether the thread hit a SW breakpoint,
3462 trust it. Targets that can tell also adjust the PC
3464 if (target_supports_stopped_by_sw_breakpoint ())
3467 /* Note that relying on whether a breakpoint is planted in memory to
3468 determine this can fail. E.g,. the breakpoint could have been
3469 removed since. Or the thread could have been told to step an
3470 instruction the size of a breakpoint instruction, and only
3471 _after_ was a breakpoint inserted at its address. */
3473 /* If this target does not decrement the PC after breakpoints, then
3474 we have nothing to do. */
3475 regcache
= get_thread_regcache (ecs
->ptid
);
3476 gdbarch
= get_regcache_arch (regcache
);
3478 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3482 aspace
= get_regcache_aspace (regcache
);
3484 /* Find the location where (if we've hit a breakpoint) the
3485 breakpoint would be. */
3486 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3488 /* If the target can't tell whether a software breakpoint triggered,
3489 fallback to figuring it out based on breakpoints we think were
3490 inserted in the target, and on whether the thread was stepped or
3493 /* Check whether there actually is a software breakpoint inserted at
3496 If in non-stop mode, a race condition is possible where we've
3497 removed a breakpoint, but stop events for that breakpoint were
3498 already queued and arrive later. To suppress those spurious
3499 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3500 and retire them after a number of stop events are reported. Note
3501 this is an heuristic and can thus get confused. The real fix is
3502 to get the "stopped by SW BP and needs adjustment" info out of
3503 the target/kernel (and thus never reach here; see above). */
3504 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3505 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3507 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
3509 if (record_full_is_used ())
3510 record_full_gdb_operation_disable_set ();
3512 /* When using hardware single-step, a SIGTRAP is reported for both
3513 a completed single-step and a software breakpoint. Need to
3514 differentiate between the two, as the latter needs adjusting
3515 but the former does not.
3517 The SIGTRAP can be due to a completed hardware single-step only if
3518 - we didn't insert software single-step breakpoints
3519 - this thread is currently being stepped
3521 If any of these events did not occur, we must have stopped due
3522 to hitting a software breakpoint, and have to back up to the
3525 As a special case, we could have hardware single-stepped a
3526 software breakpoint. In this case (prev_pc == breakpoint_pc),
3527 we also need to back up to the breakpoint address. */
3529 if (thread_has_single_step_breakpoints_set (ecs
->event_thread
)
3530 || !currently_stepping (ecs
->event_thread
)
3531 || (ecs
->event_thread
->stepped_breakpoint
3532 && ecs
->event_thread
->prev_pc
== breakpoint_pc
))
3533 regcache_write_pc (regcache
, breakpoint_pc
);
3535 do_cleanups (old_cleanups
);
3540 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3542 for (frame
= get_prev_frame (frame
);
3544 frame
= get_prev_frame (frame
))
3546 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3548 if (get_frame_type (frame
) != INLINE_FRAME
)
3555 /* Auxiliary function that handles syscall entry/return events.
3556 It returns 1 if the inferior should keep going (and GDB
3557 should ignore the event), or 0 if the event deserves to be
3561 handle_syscall_event (struct execution_control_state
*ecs
)
3563 struct regcache
*regcache
;
3566 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3567 context_switch (ecs
->ptid
);
3569 regcache
= get_thread_regcache (ecs
->ptid
);
3570 syscall_number
= ecs
->ws
.value
.syscall_number
;
3571 stop_pc
= regcache_read_pc (regcache
);
3573 if (catch_syscall_enabled () > 0
3574 && catching_syscall_number (syscall_number
) > 0)
3577 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3580 ecs
->event_thread
->control
.stop_bpstat
3581 = bpstat_stop_status (get_regcache_aspace (regcache
),
3582 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3584 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3586 /* Catchpoint hit. */
3591 /* If no catchpoint triggered for this, then keep going. */
3596 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3599 fill_in_stop_func (struct gdbarch
*gdbarch
,
3600 struct execution_control_state
*ecs
)
3602 if (!ecs
->stop_func_filled_in
)
3604 /* Don't care about return value; stop_func_start and stop_func_name
3605 will both be 0 if it doesn't work. */
3606 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3607 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3608 ecs
->stop_func_start
3609 += gdbarch_deprecated_function_start_offset (gdbarch
);
3611 if (gdbarch_skip_entrypoint_p (gdbarch
))
3612 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
3613 ecs
->stop_func_start
);
3615 ecs
->stop_func_filled_in
= 1;
3620 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
3622 static enum stop_kind
3623 get_inferior_stop_soon (ptid_t ptid
)
3625 struct inferior
*inf
= find_inferior_ptid (ptid
);
3627 gdb_assert (inf
!= NULL
);
3628 return inf
->control
.stop_soon
;
3631 /* Given an execution control state that has been freshly filled in by
3632 an event from the inferior, figure out what it means and take
3635 The alternatives are:
3637 1) stop_waiting and return; to really stop and return to the
3640 2) keep_going and return; to wait for the next event (set
3641 ecs->event_thread->stepping_over_breakpoint to 1 to single step
3645 handle_inferior_event (struct execution_control_state
*ecs
)
3647 enum stop_kind stop_soon
;
3649 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3651 /* We had an event in the inferior, but we are not interested in
3652 handling it at this level. The lower layers have already
3653 done what needs to be done, if anything.
3655 One of the possible circumstances for this is when the
3656 inferior produces output for the console. The inferior has
3657 not stopped, and we are ignoring the event. Another possible
3658 circumstance is any event which the lower level knows will be
3659 reported multiple times without an intervening resume. */
3661 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3662 prepare_to_wait (ecs
);
3666 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3667 && target_can_async_p () && !sync_execution
)
3669 /* There were no unwaited-for children left in the target, but,
3670 we're not synchronously waiting for events either. Just
3671 ignore. Otherwise, if we were running a synchronous
3672 execution command, we need to cancel it and give the user
3673 back the terminal. */
3675 fprintf_unfiltered (gdb_stdlog
,
3676 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3677 prepare_to_wait (ecs
);
3681 /* Cache the last pid/waitstatus. */
3682 set_last_target_status (ecs
->ptid
, ecs
->ws
);
3684 /* Always clear state belonging to the previous time we stopped. */
3685 stop_stack_dummy
= STOP_NONE
;
3687 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3689 /* No unwaited-for children left. IOW, all resumed children
3692 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3694 stop_print_frame
= 0;
3699 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3700 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3702 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3703 /* If it's a new thread, add it to the thread database. */
3704 if (ecs
->event_thread
== NULL
)
3705 ecs
->event_thread
= add_thread (ecs
->ptid
);
3707 /* Disable range stepping. If the next step request could use a
3708 range, this will be end up re-enabled then. */
3709 ecs
->event_thread
->control
.may_range_step
= 0;
3712 /* Dependent on valid ECS->EVENT_THREAD. */
3713 adjust_pc_after_break (ecs
);
3715 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3716 reinit_frame_cache ();
3718 breakpoint_retire_moribund ();
3720 /* First, distinguish signals caused by the debugger from signals
3721 that have to do with the program's own actions. Note that
3722 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3723 on the operating system version. Here we detect when a SIGILL or
3724 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3725 something similar for SIGSEGV, since a SIGSEGV will be generated
3726 when we're trying to execute a breakpoint instruction on a
3727 non-executable stack. This happens for call dummy breakpoints
3728 for architectures like SPARC that place call dummies on the
3730 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3731 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3732 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3733 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3735 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3737 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3738 regcache_read_pc (regcache
)))
3741 fprintf_unfiltered (gdb_stdlog
,
3742 "infrun: Treating signal as SIGTRAP\n");
3743 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3747 /* Mark the non-executing threads accordingly. In all-stop, all
3748 threads of all processes are stopped when we get any event
3749 reported. In non-stop mode, only the event thread stops. If
3750 we're handling a process exit in non-stop mode, there's nothing
3751 to do, as threads of the dead process are gone, and threads of
3752 any other process were left running. */
3754 set_executing (minus_one_ptid
, 0);
3755 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3756 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3757 set_executing (ecs
->ptid
, 0);
3759 switch (ecs
->ws
.kind
)
3761 case TARGET_WAITKIND_LOADED
:
3763 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3764 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3765 context_switch (ecs
->ptid
);
3766 /* Ignore gracefully during startup of the inferior, as it might
3767 be the shell which has just loaded some objects, otherwise
3768 add the symbols for the newly loaded objects. Also ignore at
3769 the beginning of an attach or remote session; we will query
3770 the full list of libraries once the connection is
3773 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
3774 if (stop_soon
== NO_STOP_QUIETLY
)
3776 struct regcache
*regcache
;
3778 regcache
= get_thread_regcache (ecs
->ptid
);
3780 handle_solib_event ();
3782 ecs
->event_thread
->control
.stop_bpstat
3783 = bpstat_stop_status (get_regcache_aspace (regcache
),
3784 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3786 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3788 /* A catchpoint triggered. */
3789 process_event_stop_test (ecs
);
3793 /* If requested, stop when the dynamic linker notifies
3794 gdb of events. This allows the user to get control
3795 and place breakpoints in initializer routines for
3796 dynamically loaded objects (among other things). */
3797 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3798 if (stop_on_solib_events
)
3800 /* Make sure we print "Stopped due to solib-event" in
3802 stop_print_frame
= 1;
3809 /* If we are skipping through a shell, or through shared library
3810 loading that we aren't interested in, resume the program. If
3811 we're running the program normally, also resume. */
3812 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3814 /* Loading of shared libraries might have changed breakpoint
3815 addresses. Make sure new breakpoints are inserted. */
3816 if (stop_soon
== NO_STOP_QUIETLY
)
3817 insert_breakpoints ();
3818 resume (0, GDB_SIGNAL_0
);
3819 prepare_to_wait (ecs
);
3823 /* But stop if we're attaching or setting up a remote
3825 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3826 || stop_soon
== STOP_QUIETLY_REMOTE
)
3829 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3834 internal_error (__FILE__
, __LINE__
,
3835 _("unhandled stop_soon: %d"), (int) stop_soon
);
3837 case TARGET_WAITKIND_SPURIOUS
:
3839 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3840 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3841 context_switch (ecs
->ptid
);
3842 resume (0, GDB_SIGNAL_0
);
3843 prepare_to_wait (ecs
);
3846 case TARGET_WAITKIND_EXITED
:
3847 case TARGET_WAITKIND_SIGNALLED
:
3850 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3851 fprintf_unfiltered (gdb_stdlog
,
3852 "infrun: TARGET_WAITKIND_EXITED\n");
3854 fprintf_unfiltered (gdb_stdlog
,
3855 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3858 inferior_ptid
= ecs
->ptid
;
3859 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
3860 set_current_program_space (current_inferior ()->pspace
);
3861 handle_vfork_child_exec_or_exit (0);
3862 target_terminal_ours (); /* Must do this before mourn anyway. */
3864 /* Clearing any previous state of convenience variables. */
3865 clear_exit_convenience_vars ();
3867 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3869 /* Record the exit code in the convenience variable $_exitcode, so
3870 that the user can inspect this again later. */
3871 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3872 (LONGEST
) ecs
->ws
.value
.integer
);
3874 /* Also record this in the inferior itself. */
3875 current_inferior ()->has_exit_code
= 1;
3876 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3878 /* Support the --return-child-result option. */
3879 return_child_result_value
= ecs
->ws
.value
.integer
;
3881 observer_notify_exited (ecs
->ws
.value
.integer
);
3885 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3886 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3888 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
3890 /* Set the value of the internal variable $_exitsignal,
3891 which holds the signal uncaught by the inferior. */
3892 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
3893 gdbarch_gdb_signal_to_target (gdbarch
,
3894 ecs
->ws
.value
.sig
));
3898 /* We don't have access to the target's method used for
3899 converting between signal numbers (GDB's internal
3900 representation <-> target's representation).
3901 Therefore, we cannot do a good job at displaying this
3902 information to the user. It's better to just warn
3903 her about it (if infrun debugging is enabled), and
3906 fprintf_filtered (gdb_stdlog
, _("\
3907 Cannot fill $_exitsignal with the correct signal number.\n"));
3910 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
3913 gdb_flush (gdb_stdout
);
3914 target_mourn_inferior ();
3915 stop_print_frame
= 0;
3919 /* The following are the only cases in which we keep going;
3920 the above cases end in a continue or goto. */
3921 case TARGET_WAITKIND_FORKED
:
3922 case TARGET_WAITKIND_VFORKED
:
3925 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3926 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3928 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
3931 /* Check whether the inferior is displaced stepping. */
3933 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3934 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3935 struct displaced_step_inferior_state
*displaced
3936 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3938 /* If checking displaced stepping is supported, and thread
3939 ecs->ptid is displaced stepping. */
3940 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3942 struct inferior
*parent_inf
3943 = find_inferior_ptid (ecs
->ptid
);
3944 struct regcache
*child_regcache
;
3945 CORE_ADDR parent_pc
;
3947 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3948 indicating that the displaced stepping of syscall instruction
3949 has been done. Perform cleanup for parent process here. Note
3950 that this operation also cleans up the child process for vfork,
3951 because their pages are shared. */
3952 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3954 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3956 /* Restore scratch pad for child process. */
3957 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3960 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3961 the child's PC is also within the scratchpad. Set the child's PC
3962 to the parent's PC value, which has already been fixed up.
3963 FIXME: we use the parent's aspace here, although we're touching
3964 the child, because the child hasn't been added to the inferior
3965 list yet at this point. */
3968 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3970 parent_inf
->aspace
);
3971 /* Read PC value of parent process. */
3972 parent_pc
= regcache_read_pc (regcache
);
3974 if (debug_displaced
)
3975 fprintf_unfiltered (gdb_stdlog
,
3976 "displaced: write child pc from %s to %s\n",
3978 regcache_read_pc (child_regcache
)),
3979 paddress (gdbarch
, parent_pc
));
3981 regcache_write_pc (child_regcache
, parent_pc
);
3985 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3986 context_switch (ecs
->ptid
);
3988 /* Immediately detach breakpoints from the child before there's
3989 any chance of letting the user delete breakpoints from the
3990 breakpoint lists. If we don't do this early, it's easy to
3991 leave left over traps in the child, vis: "break foo; catch
3992 fork; c; <fork>; del; c; <child calls foo>". We only follow
3993 the fork on the last `continue', and by that time the
3994 breakpoint at "foo" is long gone from the breakpoint table.
3995 If we vforked, then we don't need to unpatch here, since both
3996 parent and child are sharing the same memory pages; we'll
3997 need to unpatch at follow/detach time instead to be certain
3998 that new breakpoints added between catchpoint hit time and
3999 vfork follow are detached. */
4000 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
4002 /* This won't actually modify the breakpoint list, but will
4003 physically remove the breakpoints from the child. */
4004 detach_breakpoints (ecs
->ws
.value
.related_pid
);
4007 delete_just_stopped_threads_single_step_breakpoints ();
4009 /* In case the event is caught by a catchpoint, remember that
4010 the event is to be followed at the next resume of the thread,
4011 and not immediately. */
4012 ecs
->event_thread
->pending_follow
= ecs
->ws
;
4014 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4016 ecs
->event_thread
->control
.stop_bpstat
4017 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4018 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4020 /* If no catchpoint triggered for this, then keep going. Note
4021 that we're interested in knowing the bpstat actually causes a
4022 stop, not just if it may explain the signal. Software
4023 watchpoints, for example, always appear in the bpstat. */
4024 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4030 = (follow_fork_mode_string
== follow_fork_mode_child
);
4032 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4034 should_resume
= follow_fork ();
4037 child
= ecs
->ws
.value
.related_pid
;
4039 /* In non-stop mode, also resume the other branch. */
4040 if (non_stop
&& !detach_fork
)
4043 switch_to_thread (parent
);
4045 switch_to_thread (child
);
4047 ecs
->event_thread
= inferior_thread ();
4048 ecs
->ptid
= inferior_ptid
;
4053 switch_to_thread (child
);
4055 switch_to_thread (parent
);
4057 ecs
->event_thread
= inferior_thread ();
4058 ecs
->ptid
= inferior_ptid
;
4066 process_event_stop_test (ecs
);
4069 case TARGET_WAITKIND_VFORK_DONE
:
4070 /* Done with the shared memory region. Re-insert breakpoints in
4071 the parent, and keep going. */
4074 fprintf_unfiltered (gdb_stdlog
,
4075 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
4077 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4078 context_switch (ecs
->ptid
);
4080 current_inferior ()->waiting_for_vfork_done
= 0;
4081 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
4082 /* This also takes care of reinserting breakpoints in the
4083 previously locked inferior. */
4087 case TARGET_WAITKIND_EXECD
:
4089 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
4091 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4092 context_switch (ecs
->ptid
);
4094 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4096 /* Do whatever is necessary to the parent branch of the vfork. */
4097 handle_vfork_child_exec_or_exit (1);
4099 /* This causes the eventpoints and symbol table to be reset.
4100 Must do this now, before trying to determine whether to
4102 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
4104 ecs
->event_thread
->control
.stop_bpstat
4105 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4106 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4108 /* Note that this may be referenced from inside
4109 bpstat_stop_status above, through inferior_has_execd. */
4110 xfree (ecs
->ws
.value
.execd_pathname
);
4111 ecs
->ws
.value
.execd_pathname
= NULL
;
4113 /* If no catchpoint triggered for this, then keep going. */
4114 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4116 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4120 process_event_stop_test (ecs
);
4123 /* Be careful not to try to gather much state about a thread
4124 that's in a syscall. It's frequently a losing proposition. */
4125 case TARGET_WAITKIND_SYSCALL_ENTRY
:
4127 fprintf_unfiltered (gdb_stdlog
,
4128 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
4129 /* Getting the current syscall number. */
4130 if (handle_syscall_event (ecs
) == 0)
4131 process_event_stop_test (ecs
);
4134 /* Before examining the threads further, step this thread to
4135 get it entirely out of the syscall. (We get notice of the
4136 event when the thread is just on the verge of exiting a
4137 syscall. Stepping one instruction seems to get it back
4139 case TARGET_WAITKIND_SYSCALL_RETURN
:
4141 fprintf_unfiltered (gdb_stdlog
,
4142 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
4143 if (handle_syscall_event (ecs
) == 0)
4144 process_event_stop_test (ecs
);
4147 case TARGET_WAITKIND_STOPPED
:
4149 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
4150 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
4151 handle_signal_stop (ecs
);
4154 case TARGET_WAITKIND_NO_HISTORY
:
4156 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
4157 /* Reverse execution: target ran out of history info. */
4159 delete_just_stopped_threads_single_step_breakpoints ();
4160 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4161 observer_notify_no_history ();
4167 /* Come here when the program has stopped with a signal. */
4170 handle_signal_stop (struct execution_control_state
*ecs
)
4172 struct frame_info
*frame
;
4173 struct gdbarch
*gdbarch
;
4174 int stopped_by_watchpoint
;
4175 enum stop_kind stop_soon
;
4178 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
4180 /* Do we need to clean up the state of a thread that has
4181 completed a displaced single-step? (Doing so usually affects
4182 the PC, so do it here, before we set stop_pc.) */
4183 displaced_step_fixup (ecs
->ptid
,
4184 ecs
->event_thread
->suspend
.stop_signal
);
4186 /* If we either finished a single-step or hit a breakpoint, but
4187 the user wanted this thread to be stopped, pretend we got a
4188 SIG0 (generic unsignaled stop). */
4189 if (ecs
->event_thread
->stop_requested
4190 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4191 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4193 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4197 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4198 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4199 struct cleanup
*old_chain
= save_inferior_ptid ();
4201 inferior_ptid
= ecs
->ptid
;
4203 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
4204 paddress (gdbarch
, stop_pc
));
4205 if (target_stopped_by_watchpoint ())
4209 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
4211 if (target_stopped_data_address (¤t_target
, &addr
))
4212 fprintf_unfiltered (gdb_stdlog
,
4213 "infrun: stopped data address = %s\n",
4214 paddress (gdbarch
, addr
));
4216 fprintf_unfiltered (gdb_stdlog
,
4217 "infrun: (no data address available)\n");
4220 do_cleanups (old_chain
);
4223 /* This is originated from start_remote(), start_inferior() and
4224 shared libraries hook functions. */
4225 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4226 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4228 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4229 context_switch (ecs
->ptid
);
4231 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4232 stop_print_frame
= 1;
4237 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4240 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4241 context_switch (ecs
->ptid
);
4243 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4244 stop_print_frame
= 0;
4249 /* This originates from attach_command(). We need to overwrite
4250 the stop_signal here, because some kernels don't ignore a
4251 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4252 See more comments in inferior.h. On the other hand, if we
4253 get a non-SIGSTOP, report it to the user - assume the backend
4254 will handle the SIGSTOP if it should show up later.
4256 Also consider that the attach is complete when we see a
4257 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4258 target extended-remote report it instead of a SIGSTOP
4259 (e.g. gdbserver). We already rely on SIGTRAP being our
4260 signal, so this is no exception.
4262 Also consider that the attach is complete when we see a
4263 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4264 the target to stop all threads of the inferior, in case the
4265 low level attach operation doesn't stop them implicitly. If
4266 they weren't stopped implicitly, then the stub will report a
4267 GDB_SIGNAL_0, meaning: stopped for no particular reason
4268 other than GDB's request. */
4269 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4270 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4271 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4272 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4274 stop_print_frame
= 1;
4276 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4280 /* See if something interesting happened to the non-current thread. If
4281 so, then switch to that thread. */
4282 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4285 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
4287 context_switch (ecs
->ptid
);
4289 if (deprecated_context_hook
)
4290 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
4293 /* At this point, get hold of the now-current thread's frame. */
4294 frame
= get_current_frame ();
4295 gdbarch
= get_frame_arch (frame
);
4297 /* Pull the single step breakpoints out of the target. */
4298 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4300 struct regcache
*regcache
;
4301 struct address_space
*aspace
;
4304 regcache
= get_thread_regcache (ecs
->ptid
);
4305 aspace
= get_regcache_aspace (regcache
);
4306 pc
= regcache_read_pc (regcache
);
4308 /* However, before doing so, if this single-step breakpoint was
4309 actually for another thread, set this thread up for moving
4311 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
4314 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
4318 fprintf_unfiltered (gdb_stdlog
,
4319 "infrun: [%s] hit another thread's "
4320 "single-step breakpoint\n",
4321 target_pid_to_str (ecs
->ptid
));
4323 ecs
->hit_singlestep_breakpoint
= 1;
4330 fprintf_unfiltered (gdb_stdlog
,
4331 "infrun: [%s] hit its "
4332 "single-step breakpoint\n",
4333 target_pid_to_str (ecs
->ptid
));
4337 delete_just_stopped_threads_single_step_breakpoints ();
4339 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4340 && ecs
->event_thread
->control
.trap_expected
4341 && ecs
->event_thread
->stepping_over_watchpoint
)
4342 stopped_by_watchpoint
= 0;
4344 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4346 /* If necessary, step over this watchpoint. We'll be back to display
4348 if (stopped_by_watchpoint
4349 && (target_have_steppable_watchpoint
4350 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4352 /* At this point, we are stopped at an instruction which has
4353 attempted to write to a piece of memory under control of
4354 a watchpoint. The instruction hasn't actually executed
4355 yet. If we were to evaluate the watchpoint expression
4356 now, we would get the old value, and therefore no change
4357 would seem to have occurred.
4359 In order to make watchpoints work `right', we really need
4360 to complete the memory write, and then evaluate the
4361 watchpoint expression. We do this by single-stepping the
4364 It may not be necessary to disable the watchpoint to step over
4365 it. For example, the PA can (with some kernel cooperation)
4366 single step over a watchpoint without disabling the watchpoint.
4368 It is far more common to need to disable a watchpoint to step
4369 the inferior over it. If we have non-steppable watchpoints,
4370 we must disable the current watchpoint; it's simplest to
4371 disable all watchpoints.
4373 Any breakpoint at PC must also be stepped over -- if there's
4374 one, it will have already triggered before the watchpoint
4375 triggered, and we either already reported it to the user, or
4376 it didn't cause a stop and we called keep_going. In either
4377 case, if there was a breakpoint at PC, we must be trying to
4379 ecs
->event_thread
->stepping_over_watchpoint
= 1;
4384 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4385 ecs
->event_thread
->stepping_over_watchpoint
= 0;
4386 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4387 ecs
->event_thread
->control
.stop_step
= 0;
4388 stop_print_frame
= 1;
4389 stopped_by_random_signal
= 0;
4391 /* Hide inlined functions starting here, unless we just performed stepi or
4392 nexti. After stepi and nexti, always show the innermost frame (not any
4393 inline function call sites). */
4394 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4396 struct address_space
*aspace
=
4397 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4399 /* skip_inline_frames is expensive, so we avoid it if we can
4400 determine that the address is one where functions cannot have
4401 been inlined. This improves performance with inferiors that
4402 load a lot of shared libraries, because the solib event
4403 breakpoint is defined as the address of a function (i.e. not
4404 inline). Note that we have to check the previous PC as well
4405 as the current one to catch cases when we have just
4406 single-stepped off a breakpoint prior to reinstating it.
4407 Note that we're assuming that the code we single-step to is
4408 not inline, but that's not definitive: there's nothing
4409 preventing the event breakpoint function from containing
4410 inlined code, and the single-step ending up there. If the
4411 user had set a breakpoint on that inlined code, the missing
4412 skip_inline_frames call would break things. Fortunately
4413 that's an extremely unlikely scenario. */
4414 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4415 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4416 && ecs
->event_thread
->control
.trap_expected
4417 && pc_at_non_inline_function (aspace
,
4418 ecs
->event_thread
->prev_pc
,
4421 skip_inline_frames (ecs
->ptid
);
4423 /* Re-fetch current thread's frame in case that invalidated
4425 frame
= get_current_frame ();
4426 gdbarch
= get_frame_arch (frame
);
4430 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4431 && ecs
->event_thread
->control
.trap_expected
4432 && gdbarch_single_step_through_delay_p (gdbarch
)
4433 && currently_stepping (ecs
->event_thread
))
4435 /* We're trying to step off a breakpoint. Turns out that we're
4436 also on an instruction that needs to be stepped multiple
4437 times before it's been fully executing. E.g., architectures
4438 with a delay slot. It needs to be stepped twice, once for
4439 the instruction and once for the delay slot. */
4440 int step_through_delay
4441 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4443 if (debug_infrun
&& step_through_delay
)
4444 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4445 if (ecs
->event_thread
->control
.step_range_end
== 0
4446 && step_through_delay
)
4448 /* The user issued a continue when stopped at a breakpoint.
4449 Set up for another trap and get out of here. */
4450 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4454 else if (step_through_delay
)
4456 /* The user issued a step when stopped at a breakpoint.
4457 Maybe we should stop, maybe we should not - the delay
4458 slot *might* correspond to a line of source. In any
4459 case, don't decide that here, just set
4460 ecs->stepping_over_breakpoint, making sure we
4461 single-step again before breakpoints are re-inserted. */
4462 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4466 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4467 handles this event. */
4468 ecs
->event_thread
->control
.stop_bpstat
4469 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4470 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4472 /* Following in case break condition called a
4474 stop_print_frame
= 1;
4476 /* This is where we handle "moribund" watchpoints. Unlike
4477 software breakpoints traps, hardware watchpoint traps are
4478 always distinguishable from random traps. If no high-level
4479 watchpoint is associated with the reported stop data address
4480 anymore, then the bpstat does not explain the signal ---
4481 simply make sure to ignore it if `stopped_by_watchpoint' is
4485 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4486 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4488 && stopped_by_watchpoint
)
4489 fprintf_unfiltered (gdb_stdlog
,
4490 "infrun: no user watchpoint explains "
4491 "watchpoint SIGTRAP, ignoring\n");
4493 /* NOTE: cagney/2003-03-29: These checks for a random signal
4494 at one stage in the past included checks for an inferior
4495 function call's call dummy's return breakpoint. The original
4496 comment, that went with the test, read:
4498 ``End of a stack dummy. Some systems (e.g. Sony news) give
4499 another signal besides SIGTRAP, so check here as well as
4502 If someone ever tries to get call dummys on a
4503 non-executable stack to work (where the target would stop
4504 with something like a SIGSEGV), then those tests might need
4505 to be re-instated. Given, however, that the tests were only
4506 enabled when momentary breakpoints were not being used, I
4507 suspect that it won't be the case.
4509 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4510 be necessary for call dummies on a non-executable stack on
4513 /* See if the breakpoints module can explain the signal. */
4515 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4516 ecs
->event_thread
->suspend
.stop_signal
);
4518 /* Maybe this was a trap for a software breakpoint that has since
4520 if (random_signal
&& target_stopped_by_sw_breakpoint ())
4522 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
4524 struct regcache
*regcache
;
4527 /* Re-adjust PC to what the program would see if GDB was not
4529 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
4530 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4533 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
4535 if (record_full_is_used ())
4536 record_full_gdb_operation_disable_set ();
4538 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
4540 do_cleanups (old_cleanups
);
4545 /* A delayed software breakpoint event. Ignore the trap. */
4547 fprintf_unfiltered (gdb_stdlog
,
4548 "infrun: delayed software breakpoint "
4549 "trap, ignoring\n");
4554 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
4555 has since been removed. */
4556 if (random_signal
&& target_stopped_by_hw_breakpoint ())
4558 /* A delayed hardware breakpoint event. Ignore the trap. */
4560 fprintf_unfiltered (gdb_stdlog
,
4561 "infrun: delayed hardware breakpoint/watchpoint "
4562 "trap, ignoring\n");
4566 /* If not, perhaps stepping/nexting can. */
4568 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4569 && currently_stepping (ecs
->event_thread
));
4571 /* Perhaps the thread hit a single-step breakpoint of _another_
4572 thread. Single-step breakpoints are transparent to the
4573 breakpoints module. */
4575 random_signal
= !ecs
->hit_singlestep_breakpoint
;
4577 /* No? Perhaps we got a moribund watchpoint. */
4579 random_signal
= !stopped_by_watchpoint
;
4581 /* For the program's own signals, act according to
4582 the signal handling tables. */
4586 /* Signal not for debugging purposes. */
4587 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
4588 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
4591 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
4592 gdb_signal_to_symbol_string (stop_signal
));
4594 stopped_by_random_signal
= 1;
4596 /* Always stop on signals if we're either just gaining control
4597 of the program, or the user explicitly requested this thread
4598 to remain stopped. */
4599 if (stop_soon
!= NO_STOP_QUIETLY
4600 || ecs
->event_thread
->stop_requested
4602 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4608 /* Notify observers the signal has "handle print" set. Note we
4609 returned early above if stopping; normal_stop handles the
4610 printing in that case. */
4611 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4613 /* The signal table tells us to print about this signal. */
4614 target_terminal_ours_for_output ();
4615 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
4616 target_terminal_inferior ();
4619 /* Clear the signal if it should not be passed. */
4620 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4621 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4623 if (ecs
->event_thread
->prev_pc
== stop_pc
4624 && ecs
->event_thread
->control
.trap_expected
4625 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4627 /* We were just starting a new sequence, attempting to
4628 single-step off of a breakpoint and expecting a SIGTRAP.
4629 Instead this signal arrives. This signal will take us out
4630 of the stepping range so GDB needs to remember to, when
4631 the signal handler returns, resume stepping off that
4633 /* To simplify things, "continue" is forced to use the same
4634 code paths as single-step - set a breakpoint at the
4635 signal return address and then, once hit, step off that
4638 fprintf_unfiltered (gdb_stdlog
,
4639 "infrun: signal arrived while stepping over "
4642 insert_hp_step_resume_breakpoint_at_frame (frame
);
4643 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4644 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4645 ecs
->event_thread
->control
.trap_expected
= 0;
4647 /* If we were nexting/stepping some other thread, switch to
4648 it, so that we don't continue it, losing control. */
4649 if (!switch_back_to_stepped_thread (ecs
))
4654 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4655 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4656 || ecs
->event_thread
->control
.step_range_end
== 1)
4657 && frame_id_eq (get_stack_frame_id (frame
),
4658 ecs
->event_thread
->control
.step_stack_frame_id
)
4659 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4661 /* The inferior is about to take a signal that will take it
4662 out of the single step range. Set a breakpoint at the
4663 current PC (which is presumably where the signal handler
4664 will eventually return) and then allow the inferior to
4667 Note that this is only needed for a signal delivered
4668 while in the single-step range. Nested signals aren't a
4669 problem as they eventually all return. */
4671 fprintf_unfiltered (gdb_stdlog
,
4672 "infrun: signal may take us out of "
4673 "single-step range\n");
4675 insert_hp_step_resume_breakpoint_at_frame (frame
);
4676 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4677 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4678 ecs
->event_thread
->control
.trap_expected
= 0;
4683 /* Note: step_resume_breakpoint may be non-NULL. This occures
4684 when either there's a nested signal, or when there's a
4685 pending signal enabled just as the signal handler returns
4686 (leaving the inferior at the step-resume-breakpoint without
4687 actually executing it). Either way continue until the
4688 breakpoint is really hit. */
4690 if (!switch_back_to_stepped_thread (ecs
))
4693 fprintf_unfiltered (gdb_stdlog
,
4694 "infrun: random signal, keep going\n");
4701 process_event_stop_test (ecs
);
4704 /* Come here when we've got some debug event / signal we can explain
4705 (IOW, not a random signal), and test whether it should cause a
4706 stop, or whether we should resume the inferior (transparently).
4707 E.g., could be a breakpoint whose condition evaluates false; we
4708 could be still stepping within the line; etc. */
4711 process_event_stop_test (struct execution_control_state
*ecs
)
4713 struct symtab_and_line stop_pc_sal
;
4714 struct frame_info
*frame
;
4715 struct gdbarch
*gdbarch
;
4716 CORE_ADDR jmp_buf_pc
;
4717 struct bpstat_what what
;
4719 /* Handle cases caused by hitting a breakpoint. */
4721 frame
= get_current_frame ();
4722 gdbarch
= get_frame_arch (frame
);
4724 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4726 if (what
.call_dummy
)
4728 stop_stack_dummy
= what
.call_dummy
;
4731 /* If we hit an internal event that triggers symbol changes, the
4732 current frame will be invalidated within bpstat_what (e.g., if we
4733 hit an internal solib event). Re-fetch it. */
4734 frame
= get_current_frame ();
4735 gdbarch
= get_frame_arch (frame
);
4737 switch (what
.main_action
)
4739 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4740 /* If we hit the breakpoint at longjmp while stepping, we
4741 install a momentary breakpoint at the target of the
4745 fprintf_unfiltered (gdb_stdlog
,
4746 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4748 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4750 if (what
.is_longjmp
)
4752 struct value
*arg_value
;
4754 /* If we set the longjmp breakpoint via a SystemTap probe,
4755 then use it to extract the arguments. The destination PC
4756 is the third argument to the probe. */
4757 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4760 jmp_buf_pc
= value_as_address (arg_value
);
4761 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
4763 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4764 || !gdbarch_get_longjmp_target (gdbarch
,
4765 frame
, &jmp_buf_pc
))
4768 fprintf_unfiltered (gdb_stdlog
,
4769 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4770 "(!gdbarch_get_longjmp_target)\n");
4775 /* Insert a breakpoint at resume address. */
4776 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4779 check_exception_resume (ecs
, frame
);
4783 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4785 struct frame_info
*init_frame
;
4787 /* There are several cases to consider.
4789 1. The initiating frame no longer exists. In this case we
4790 must stop, because the exception or longjmp has gone too
4793 2. The initiating frame exists, and is the same as the
4794 current frame. We stop, because the exception or longjmp
4797 3. The initiating frame exists and is different from the
4798 current frame. This means the exception or longjmp has
4799 been caught beneath the initiating frame, so keep going.
4801 4. longjmp breakpoint has been placed just to protect
4802 against stale dummy frames and user is not interested in
4803 stopping around longjmps. */
4806 fprintf_unfiltered (gdb_stdlog
,
4807 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4809 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4811 delete_exception_resume_breakpoint (ecs
->event_thread
);
4813 if (what
.is_longjmp
)
4815 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
4817 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4825 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4829 struct frame_id current_id
4830 = get_frame_id (get_current_frame ());
4831 if (frame_id_eq (current_id
,
4832 ecs
->event_thread
->initiating_frame
))
4834 /* Case 2. Fall through. */
4844 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
4846 delete_step_resume_breakpoint (ecs
->event_thread
);
4848 end_stepping_range (ecs
);
4852 case BPSTAT_WHAT_SINGLE
:
4854 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4855 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4856 /* Still need to check other stuff, at least the case where we
4857 are stepping and step out of the right range. */
4860 case BPSTAT_WHAT_STEP_RESUME
:
4862 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4864 delete_step_resume_breakpoint (ecs
->event_thread
);
4865 if (ecs
->event_thread
->control
.proceed_to_finish
4866 && execution_direction
== EXEC_REVERSE
)
4868 struct thread_info
*tp
= ecs
->event_thread
;
4870 /* We are finishing a function in reverse, and just hit the
4871 step-resume breakpoint at the start address of the
4872 function, and we're almost there -- just need to back up
4873 by one more single-step, which should take us back to the
4875 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4879 fill_in_stop_func (gdbarch
, ecs
);
4880 if (stop_pc
== ecs
->stop_func_start
4881 && execution_direction
== EXEC_REVERSE
)
4883 /* We are stepping over a function call in reverse, and just
4884 hit the step-resume breakpoint at the start address of
4885 the function. Go back to single-stepping, which should
4886 take us back to the function call. */
4887 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4893 case BPSTAT_WHAT_STOP_NOISY
:
4895 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4896 stop_print_frame
= 1;
4898 /* Assume the thread stopped for a breapoint. We'll still check
4899 whether a/the breakpoint is there when the thread is next
4901 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4906 case BPSTAT_WHAT_STOP_SILENT
:
4908 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4909 stop_print_frame
= 0;
4911 /* Assume the thread stopped for a breapoint. We'll still check
4912 whether a/the breakpoint is there when the thread is next
4914 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4918 case BPSTAT_WHAT_HP_STEP_RESUME
:
4920 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4922 delete_step_resume_breakpoint (ecs
->event_thread
);
4923 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4925 /* Back when the step-resume breakpoint was inserted, we
4926 were trying to single-step off a breakpoint. Go back to
4928 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4929 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4935 case BPSTAT_WHAT_KEEP_CHECKING
:
4939 /* If we stepped a permanent breakpoint and we had a high priority
4940 step-resume breakpoint for the address we stepped, but we didn't
4941 hit it, then we must have stepped into the signal handler. The
4942 step-resume was only necessary to catch the case of _not_
4943 stepping into the handler, so delete it, and fall through to
4944 checking whether the step finished. */
4945 if (ecs
->event_thread
->stepped_breakpoint
)
4947 struct breakpoint
*sr_bp
4948 = ecs
->event_thread
->control
.step_resume_breakpoint
;
4950 if (sr_bp
->loc
->permanent
4951 && sr_bp
->type
== bp_hp_step_resume
4952 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
4955 fprintf_unfiltered (gdb_stdlog
,
4956 "infrun: stepped permanent breakpoint, stopped in "
4958 delete_step_resume_breakpoint (ecs
->event_thread
);
4959 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4963 /* We come here if we hit a breakpoint but should not stop for it.
4964 Possibly we also were stepping and should stop for that. So fall
4965 through and test for stepping. But, if not stepping, do not
4968 /* In all-stop mode, if we're currently stepping but have stopped in
4969 some other thread, we need to switch back to the stepped thread. */
4970 if (switch_back_to_stepped_thread (ecs
))
4973 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4976 fprintf_unfiltered (gdb_stdlog
,
4977 "infrun: step-resume breakpoint is inserted\n");
4979 /* Having a step-resume breakpoint overrides anything
4980 else having to do with stepping commands until
4981 that breakpoint is reached. */
4986 if (ecs
->event_thread
->control
.step_range_end
== 0)
4989 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4990 /* Likewise if we aren't even stepping. */
4995 /* Re-fetch current thread's frame in case the code above caused
4996 the frame cache to be re-initialized, making our FRAME variable
4997 a dangling pointer. */
4998 frame
= get_current_frame ();
4999 gdbarch
= get_frame_arch (frame
);
5000 fill_in_stop_func (gdbarch
, ecs
);
5002 /* If stepping through a line, keep going if still within it.
5004 Note that step_range_end is the address of the first instruction
5005 beyond the step range, and NOT the address of the last instruction
5008 Note also that during reverse execution, we may be stepping
5009 through a function epilogue and therefore must detect when
5010 the current-frame changes in the middle of a line. */
5012 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
5013 && (execution_direction
!= EXEC_REVERSE
5014 || frame_id_eq (get_frame_id (frame
),
5015 ecs
->event_thread
->control
.step_frame_id
)))
5019 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
5020 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
5021 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
5023 /* Tentatively re-enable range stepping; `resume' disables it if
5024 necessary (e.g., if we're stepping over a breakpoint or we
5025 have software watchpoints). */
5026 ecs
->event_thread
->control
.may_range_step
= 1;
5028 /* When stepping backward, stop at beginning of line range
5029 (unless it's the function entry point, in which case
5030 keep going back to the call point). */
5031 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
5032 && stop_pc
!= ecs
->stop_func_start
5033 && execution_direction
== EXEC_REVERSE
)
5034 end_stepping_range (ecs
);
5041 /* We stepped out of the stepping range. */
5043 /* If we are stepping at the source level and entered the runtime
5044 loader dynamic symbol resolution code...
5046 EXEC_FORWARD: we keep on single stepping until we exit the run
5047 time loader code and reach the callee's address.
5049 EXEC_REVERSE: we've already executed the callee (backward), and
5050 the runtime loader code is handled just like any other
5051 undebuggable function call. Now we need only keep stepping
5052 backward through the trampoline code, and that's handled further
5053 down, so there is nothing for us to do here. */
5055 if (execution_direction
!= EXEC_REVERSE
5056 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5057 && in_solib_dynsym_resolve_code (stop_pc
))
5059 CORE_ADDR pc_after_resolver
=
5060 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
5063 fprintf_unfiltered (gdb_stdlog
,
5064 "infrun: stepped into dynsym resolve code\n");
5066 if (pc_after_resolver
)
5068 /* Set up a step-resume breakpoint at the address
5069 indicated by SKIP_SOLIB_RESOLVER. */
5070 struct symtab_and_line sr_sal
;
5073 sr_sal
.pc
= pc_after_resolver
;
5074 sr_sal
.pspace
= get_frame_program_space (frame
);
5076 insert_step_resume_breakpoint_at_sal (gdbarch
,
5077 sr_sal
, null_frame_id
);
5084 if (ecs
->event_thread
->control
.step_range_end
!= 1
5085 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5086 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5087 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
5090 fprintf_unfiltered (gdb_stdlog
,
5091 "infrun: stepped into signal trampoline\n");
5092 /* The inferior, while doing a "step" or "next", has ended up in
5093 a signal trampoline (either by a signal being delivered or by
5094 the signal handler returning). Just single-step until the
5095 inferior leaves the trampoline (either by calling the handler
5101 /* If we're in the return path from a shared library trampoline,
5102 we want to proceed through the trampoline when stepping. */
5103 /* macro/2012-04-25: This needs to come before the subroutine
5104 call check below as on some targets return trampolines look
5105 like subroutine calls (MIPS16 return thunks). */
5106 if (gdbarch_in_solib_return_trampoline (gdbarch
,
5107 stop_pc
, ecs
->stop_func_name
)
5108 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5110 /* Determine where this trampoline returns. */
5111 CORE_ADDR real_stop_pc
;
5113 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5116 fprintf_unfiltered (gdb_stdlog
,
5117 "infrun: stepped into solib return tramp\n");
5119 /* Only proceed through if we know where it's going. */
5122 /* And put the step-breakpoint there and go until there. */
5123 struct symtab_and_line sr_sal
;
5125 init_sal (&sr_sal
); /* initialize to zeroes */
5126 sr_sal
.pc
= real_stop_pc
;
5127 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5128 sr_sal
.pspace
= get_frame_program_space (frame
);
5130 /* Do not specify what the fp should be when we stop since
5131 on some machines the prologue is where the new fp value
5133 insert_step_resume_breakpoint_at_sal (gdbarch
,
5134 sr_sal
, null_frame_id
);
5136 /* Restart without fiddling with the step ranges or
5143 /* Check for subroutine calls. The check for the current frame
5144 equalling the step ID is not necessary - the check of the
5145 previous frame's ID is sufficient - but it is a common case and
5146 cheaper than checking the previous frame's ID.
5148 NOTE: frame_id_eq will never report two invalid frame IDs as
5149 being equal, so to get into this block, both the current and
5150 previous frame must have valid frame IDs. */
5151 /* The outer_frame_id check is a heuristic to detect stepping
5152 through startup code. If we step over an instruction which
5153 sets the stack pointer from an invalid value to a valid value,
5154 we may detect that as a subroutine call from the mythical
5155 "outermost" function. This could be fixed by marking
5156 outermost frames as !stack_p,code_p,special_p. Then the
5157 initial outermost frame, before sp was valid, would
5158 have code_addr == &_start. See the comment in frame_id_eq
5160 if (!frame_id_eq (get_stack_frame_id (frame
),
5161 ecs
->event_thread
->control
.step_stack_frame_id
)
5162 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
5163 ecs
->event_thread
->control
.step_stack_frame_id
)
5164 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
5166 || (ecs
->event_thread
->control
.step_start_function
5167 != find_pc_function (stop_pc
)))))
5169 CORE_ADDR real_stop_pc
;
5172 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
5174 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
5176 /* I presume that step_over_calls is only 0 when we're
5177 supposed to be stepping at the assembly language level
5178 ("stepi"). Just stop. */
5179 /* And this works the same backward as frontward. MVS */
5180 end_stepping_range (ecs
);
5184 /* Reverse stepping through solib trampolines. */
5186 if (execution_direction
== EXEC_REVERSE
5187 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
5188 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5189 || (ecs
->stop_func_start
== 0
5190 && in_solib_dynsym_resolve_code (stop_pc
))))
5192 /* Any solib trampoline code can be handled in reverse
5193 by simply continuing to single-step. We have already
5194 executed the solib function (backwards), and a few
5195 steps will take us back through the trampoline to the
5201 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5203 /* We're doing a "next".
5205 Normal (forward) execution: set a breakpoint at the
5206 callee's return address (the address at which the caller
5209 Reverse (backward) execution. set the step-resume
5210 breakpoint at the start of the function that we just
5211 stepped into (backwards), and continue to there. When we
5212 get there, we'll need to single-step back to the caller. */
5214 if (execution_direction
== EXEC_REVERSE
)
5216 /* If we're already at the start of the function, we've either
5217 just stepped backward into a single instruction function,
5218 or stepped back out of a signal handler to the first instruction
5219 of the function. Just keep going, which will single-step back
5221 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
5223 struct symtab_and_line sr_sal
;
5225 /* Normal function call return (static or dynamic). */
5227 sr_sal
.pc
= ecs
->stop_func_start
;
5228 sr_sal
.pspace
= get_frame_program_space (frame
);
5229 insert_step_resume_breakpoint_at_sal (gdbarch
,
5230 sr_sal
, null_frame_id
);
5234 insert_step_resume_breakpoint_at_caller (frame
);
5240 /* If we are in a function call trampoline (a stub between the
5241 calling routine and the real function), locate the real
5242 function. That's what tells us (a) whether we want to step
5243 into it at all, and (b) what prologue we want to run to the
5244 end of, if we do step into it. */
5245 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
5246 if (real_stop_pc
== 0)
5247 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5248 if (real_stop_pc
!= 0)
5249 ecs
->stop_func_start
= real_stop_pc
;
5251 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
5253 struct symtab_and_line sr_sal
;
5256 sr_sal
.pc
= ecs
->stop_func_start
;
5257 sr_sal
.pspace
= get_frame_program_space (frame
);
5259 insert_step_resume_breakpoint_at_sal (gdbarch
,
5260 sr_sal
, null_frame_id
);
5265 /* If we have line number information for the function we are
5266 thinking of stepping into and the function isn't on the skip
5269 If there are several symtabs at that PC (e.g. with include
5270 files), just want to know whether *any* of them have line
5271 numbers. find_pc_line handles this. */
5273 struct symtab_and_line tmp_sal
;
5275 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5276 if (tmp_sal
.line
!= 0
5277 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
5280 if (execution_direction
== EXEC_REVERSE
)
5281 handle_step_into_function_backward (gdbarch
, ecs
);
5283 handle_step_into_function (gdbarch
, ecs
);
5288 /* If we have no line number and the step-stop-if-no-debug is
5289 set, we stop the step so that the user has a chance to switch
5290 in assembly mode. */
5291 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5292 && step_stop_if_no_debug
)
5294 end_stepping_range (ecs
);
5298 if (execution_direction
== EXEC_REVERSE
)
5300 /* If we're already at the start of the function, we've either just
5301 stepped backward into a single instruction function without line
5302 number info, or stepped back out of a signal handler to the first
5303 instruction of the function without line number info. Just keep
5304 going, which will single-step back to the caller. */
5305 if (ecs
->stop_func_start
!= stop_pc
)
5307 /* Set a breakpoint at callee's start address.
5308 From there we can step once and be back in the caller. */
5309 struct symtab_and_line sr_sal
;
5312 sr_sal
.pc
= ecs
->stop_func_start
;
5313 sr_sal
.pspace
= get_frame_program_space (frame
);
5314 insert_step_resume_breakpoint_at_sal (gdbarch
,
5315 sr_sal
, null_frame_id
);
5319 /* Set a breakpoint at callee's return address (the address
5320 at which the caller will resume). */
5321 insert_step_resume_breakpoint_at_caller (frame
);
5327 /* Reverse stepping through solib trampolines. */
5329 if (execution_direction
== EXEC_REVERSE
5330 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5332 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5333 || (ecs
->stop_func_start
== 0
5334 && in_solib_dynsym_resolve_code (stop_pc
)))
5336 /* Any solib trampoline code can be handled in reverse
5337 by simply continuing to single-step. We have already
5338 executed the solib function (backwards), and a few
5339 steps will take us back through the trampoline to the
5344 else if (in_solib_dynsym_resolve_code (stop_pc
))
5346 /* Stepped backward into the solib dynsym resolver.
5347 Set a breakpoint at its start and continue, then
5348 one more step will take us out. */
5349 struct symtab_and_line sr_sal
;
5352 sr_sal
.pc
= ecs
->stop_func_start
;
5353 sr_sal
.pspace
= get_frame_program_space (frame
);
5354 insert_step_resume_breakpoint_at_sal (gdbarch
,
5355 sr_sal
, null_frame_id
);
5361 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5363 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5364 the trampoline processing logic, however, there are some trampolines
5365 that have no names, so we should do trampoline handling first. */
5366 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5367 && ecs
->stop_func_name
== NULL
5368 && stop_pc_sal
.line
== 0)
5371 fprintf_unfiltered (gdb_stdlog
,
5372 "infrun: stepped into undebuggable function\n");
5374 /* The inferior just stepped into, or returned to, an
5375 undebuggable function (where there is no debugging information
5376 and no line number corresponding to the address where the
5377 inferior stopped). Since we want to skip this kind of code,
5378 we keep going until the inferior returns from this
5379 function - unless the user has asked us not to (via
5380 set step-mode) or we no longer know how to get back
5381 to the call site. */
5382 if (step_stop_if_no_debug
5383 || !frame_id_p (frame_unwind_caller_id (frame
)))
5385 /* If we have no line number and the step-stop-if-no-debug
5386 is set, we stop the step so that the user has a chance to
5387 switch in assembly mode. */
5388 end_stepping_range (ecs
);
5393 /* Set a breakpoint at callee's return address (the address
5394 at which the caller will resume). */
5395 insert_step_resume_breakpoint_at_caller (frame
);
5401 if (ecs
->event_thread
->control
.step_range_end
== 1)
5403 /* It is stepi or nexti. We always want to stop stepping after
5406 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5407 end_stepping_range (ecs
);
5411 if (stop_pc_sal
.line
== 0)
5413 /* We have no line number information. That means to stop
5414 stepping (does this always happen right after one instruction,
5415 when we do "s" in a function with no line numbers,
5416 or can this happen as a result of a return or longjmp?). */
5418 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5419 end_stepping_range (ecs
);
5423 /* Look for "calls" to inlined functions, part one. If the inline
5424 frame machinery detected some skipped call sites, we have entered
5425 a new inline function. */
5427 if (frame_id_eq (get_frame_id (get_current_frame ()),
5428 ecs
->event_thread
->control
.step_frame_id
)
5429 && inline_skipped_frames (ecs
->ptid
))
5431 struct symtab_and_line call_sal
;
5434 fprintf_unfiltered (gdb_stdlog
,
5435 "infrun: stepped into inlined function\n");
5437 find_frame_sal (get_current_frame (), &call_sal
);
5439 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5441 /* For "step", we're going to stop. But if the call site
5442 for this inlined function is on the same source line as
5443 we were previously stepping, go down into the function
5444 first. Otherwise stop at the call site. */
5446 if (call_sal
.line
== ecs
->event_thread
->current_line
5447 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5448 step_into_inline_frame (ecs
->ptid
);
5450 end_stepping_range (ecs
);
5455 /* For "next", we should stop at the call site if it is on a
5456 different source line. Otherwise continue through the
5457 inlined function. */
5458 if (call_sal
.line
== ecs
->event_thread
->current_line
5459 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5462 end_stepping_range (ecs
);
5467 /* Look for "calls" to inlined functions, part two. If we are still
5468 in the same real function we were stepping through, but we have
5469 to go further up to find the exact frame ID, we are stepping
5470 through a more inlined call beyond its call site. */
5472 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5473 && !frame_id_eq (get_frame_id (get_current_frame ()),
5474 ecs
->event_thread
->control
.step_frame_id
)
5475 && stepped_in_from (get_current_frame (),
5476 ecs
->event_thread
->control
.step_frame_id
))
5479 fprintf_unfiltered (gdb_stdlog
,
5480 "infrun: stepping through inlined function\n");
5482 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5485 end_stepping_range (ecs
);
5489 if ((stop_pc
== stop_pc_sal
.pc
)
5490 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5491 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5493 /* We are at the start of a different line. So stop. Note that
5494 we don't stop if we step into the middle of a different line.
5495 That is said to make things like for (;;) statements work
5498 fprintf_unfiltered (gdb_stdlog
,
5499 "infrun: stepped to a different line\n");
5500 end_stepping_range (ecs
);
5504 /* We aren't done stepping.
5506 Optimize by setting the stepping range to the line.
5507 (We might not be in the original line, but if we entered a
5508 new line in mid-statement, we continue stepping. This makes
5509 things like for(;;) statements work better.) */
5511 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5512 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5513 ecs
->event_thread
->control
.may_range_step
= 1;
5514 set_step_info (frame
, stop_pc_sal
);
5517 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5521 /* In all-stop mode, if we're currently stepping but have stopped in
5522 some other thread, we may need to switch back to the stepped
5523 thread. Returns true we set the inferior running, false if we left
5524 it stopped (and the event needs further processing). */
5527 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
5531 struct thread_info
*tp
;
5532 struct thread_info
*stepping_thread
;
5533 struct thread_info
*step_over
;
5535 /* If any thread is blocked on some internal breakpoint, and we
5536 simply need to step over that breakpoint to get it going
5537 again, do that first. */
5539 /* However, if we see an event for the stepping thread, then we
5540 know all other threads have been moved past their breakpoints
5541 already. Let the caller check whether the step is finished,
5542 etc., before deciding to move it past a breakpoint. */
5543 if (ecs
->event_thread
->control
.step_range_end
!= 0)
5546 /* Check if the current thread is blocked on an incomplete
5547 step-over, interrupted by a random signal. */
5548 if (ecs
->event_thread
->control
.trap_expected
5549 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5553 fprintf_unfiltered (gdb_stdlog
,
5554 "infrun: need to finish step-over of [%s]\n",
5555 target_pid_to_str (ecs
->event_thread
->ptid
));
5561 /* Check if the current thread is blocked by a single-step
5562 breakpoint of another thread. */
5563 if (ecs
->hit_singlestep_breakpoint
)
5567 fprintf_unfiltered (gdb_stdlog
,
5568 "infrun: need to step [%s] over single-step "
5570 target_pid_to_str (ecs
->ptid
));
5576 /* Otherwise, we no longer expect a trap in the current thread.
5577 Clear the trap_expected flag before switching back -- this is
5578 what keep_going does as well, if we call it. */
5579 ecs
->event_thread
->control
.trap_expected
= 0;
5581 /* Likewise, clear the signal if it should not be passed. */
5582 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5583 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5585 /* If scheduler locking applies even if not stepping, there's no
5586 need to walk over threads. Above we've checked whether the
5587 current thread is stepping. If some other thread not the
5588 event thread is stepping, then it must be that scheduler
5589 locking is not in effect. */
5590 if (schedlock_applies (ecs
->event_thread
))
5593 /* Look for the stepping/nexting thread, and check if any other
5594 thread other than the stepping thread needs to start a
5595 step-over. Do all step-overs before actually proceeding with
5597 stepping_thread
= NULL
;
5599 ALL_NON_EXITED_THREADS (tp
)
5601 /* Ignore threads of processes we're not resuming. */
5603 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
5606 /* When stepping over a breakpoint, we lock all threads
5607 except the one that needs to move past the breakpoint.
5608 If a non-event thread has this set, the "incomplete
5609 step-over" check above should have caught it earlier. */
5610 gdb_assert (!tp
->control
.trap_expected
);
5612 /* Did we find the stepping thread? */
5613 if (tp
->control
.step_range_end
)
5615 /* Yep. There should only one though. */
5616 gdb_assert (stepping_thread
== NULL
);
5618 /* The event thread is handled at the top, before we
5620 gdb_assert (tp
!= ecs
->event_thread
);
5622 /* If some thread other than the event thread is
5623 stepping, then scheduler locking can't be in effect,
5624 otherwise we wouldn't have resumed the current event
5625 thread in the first place. */
5626 gdb_assert (!schedlock_applies (tp
));
5628 stepping_thread
= tp
;
5630 else if (thread_still_needs_step_over (tp
))
5634 /* At the top we've returned early if the event thread
5635 is stepping. If some other thread not the event
5636 thread is stepping, then scheduler locking can't be
5637 in effect, and we can resume this thread. No need to
5638 keep looking for the stepping thread then. */
5643 if (step_over
!= NULL
)
5648 fprintf_unfiltered (gdb_stdlog
,
5649 "infrun: need to step-over [%s]\n",
5650 target_pid_to_str (tp
->ptid
));
5653 /* Only the stepping thread should have this set. */
5654 gdb_assert (tp
->control
.step_range_end
== 0);
5656 ecs
->ptid
= tp
->ptid
;
5657 ecs
->event_thread
= tp
;
5658 switch_to_thread (ecs
->ptid
);
5663 if (stepping_thread
!= NULL
)
5665 struct frame_info
*frame
;
5666 struct gdbarch
*gdbarch
;
5668 tp
= stepping_thread
;
5670 /* If the stepping thread exited, then don't try to switch
5671 back and resume it, which could fail in several different
5672 ways depending on the target. Instead, just keep going.
5674 We can find a stepping dead thread in the thread list in
5677 - The target supports thread exit events, and when the
5678 target tries to delete the thread from the thread list,
5679 inferior_ptid pointed at the exiting thread. In such
5680 case, calling delete_thread does not really remove the
5681 thread from the list; instead, the thread is left listed,
5682 with 'exited' state.
5684 - The target's debug interface does not support thread
5685 exit events, and so we have no idea whatsoever if the
5686 previously stepping thread is still alive. For that
5687 reason, we need to synchronously query the target
5689 if (is_exited (tp
->ptid
)
5690 || !target_thread_alive (tp
->ptid
))
5693 fprintf_unfiltered (gdb_stdlog
,
5694 "infrun: not switching back to "
5695 "stepped thread, it has vanished\n");
5697 delete_thread (tp
->ptid
);
5703 fprintf_unfiltered (gdb_stdlog
,
5704 "infrun: switching back to stepped thread\n");
5706 ecs
->event_thread
= tp
;
5707 ecs
->ptid
= tp
->ptid
;
5708 context_switch (ecs
->ptid
);
5710 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5711 frame
= get_current_frame ();
5712 gdbarch
= get_frame_arch (frame
);
5714 /* If the PC of the thread we were trying to single-step has
5715 changed, then that thread has trapped or been signaled,
5716 but the event has not been reported to GDB yet. Re-poll
5717 the target looking for this particular thread's event
5718 (i.e. temporarily enable schedlock) by:
5720 - setting a break at the current PC
5721 - resuming that particular thread, only (by setting
5724 This prevents us continuously moving the single-step
5725 breakpoint forward, one instruction at a time,
5728 if (stop_pc
!= tp
->prev_pc
)
5731 fprintf_unfiltered (gdb_stdlog
,
5732 "infrun: expected thread advanced also\n");
5734 /* Clear the info of the previous step-over, as it's no
5735 longer valid. It's what keep_going would do too, if
5736 we called it. Must do this before trying to insert
5737 the sss breakpoint, otherwise if we were previously
5738 trying to step over this exact address in another
5739 thread, the breakpoint ends up not installed. */
5740 clear_step_over_info ();
5742 insert_single_step_breakpoint (get_frame_arch (frame
),
5743 get_frame_address_space (frame
),
5745 ecs
->event_thread
->control
.trap_expected
= 1;
5747 resume (0, GDB_SIGNAL_0
);
5748 prepare_to_wait (ecs
);
5753 fprintf_unfiltered (gdb_stdlog
,
5754 "infrun: expected thread still "
5755 "hasn't advanced\n");
5765 /* Is thread TP in the middle of single-stepping? */
5768 currently_stepping (struct thread_info
*tp
)
5770 return ((tp
->control
.step_range_end
5771 && tp
->control
.step_resume_breakpoint
== NULL
)
5772 || tp
->control
.trap_expected
5773 || tp
->stepped_breakpoint
5774 || bpstat_should_step ());
5777 /* Inferior has stepped into a subroutine call with source code that
5778 we should not step over. Do step to the first line of code in
5782 handle_step_into_function (struct gdbarch
*gdbarch
,
5783 struct execution_control_state
*ecs
)
5785 struct compunit_symtab
*cust
;
5786 struct symtab_and_line stop_func_sal
, sr_sal
;
5788 fill_in_stop_func (gdbarch
, ecs
);
5790 cust
= find_pc_compunit_symtab (stop_pc
);
5791 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
5792 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5793 ecs
->stop_func_start
);
5795 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5796 /* Use the step_resume_break to step until the end of the prologue,
5797 even if that involves jumps (as it seems to on the vax under
5799 /* If the prologue ends in the middle of a source line, continue to
5800 the end of that source line (if it is still within the function).
5801 Otherwise, just go to end of prologue. */
5802 if (stop_func_sal
.end
5803 && stop_func_sal
.pc
!= ecs
->stop_func_start
5804 && stop_func_sal
.end
< ecs
->stop_func_end
)
5805 ecs
->stop_func_start
= stop_func_sal
.end
;
5807 /* Architectures which require breakpoint adjustment might not be able
5808 to place a breakpoint at the computed address. If so, the test
5809 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5810 ecs->stop_func_start to an address at which a breakpoint may be
5811 legitimately placed.
5813 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5814 made, GDB will enter an infinite loop when stepping through
5815 optimized code consisting of VLIW instructions which contain
5816 subinstructions corresponding to different source lines. On
5817 FR-V, it's not permitted to place a breakpoint on any but the
5818 first subinstruction of a VLIW instruction. When a breakpoint is
5819 set, GDB will adjust the breakpoint address to the beginning of
5820 the VLIW instruction. Thus, we need to make the corresponding
5821 adjustment here when computing the stop address. */
5823 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5825 ecs
->stop_func_start
5826 = gdbarch_adjust_breakpoint_address (gdbarch
,
5827 ecs
->stop_func_start
);
5830 if (ecs
->stop_func_start
== stop_pc
)
5832 /* We are already there: stop now. */
5833 end_stepping_range (ecs
);
5838 /* Put the step-breakpoint there and go until there. */
5839 init_sal (&sr_sal
); /* initialize to zeroes */
5840 sr_sal
.pc
= ecs
->stop_func_start
;
5841 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5842 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5844 /* Do not specify what the fp should be when we stop since on
5845 some machines the prologue is where the new fp value is
5847 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5849 /* And make sure stepping stops right away then. */
5850 ecs
->event_thread
->control
.step_range_end
5851 = ecs
->event_thread
->control
.step_range_start
;
5856 /* Inferior has stepped backward into a subroutine call with source
5857 code that we should not step over. Do step to the beginning of the
5858 last line of code in it. */
5861 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5862 struct execution_control_state
*ecs
)
5864 struct compunit_symtab
*cust
;
5865 struct symtab_and_line stop_func_sal
;
5867 fill_in_stop_func (gdbarch
, ecs
);
5869 cust
= find_pc_compunit_symtab (stop_pc
);
5870 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
5871 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5872 ecs
->stop_func_start
);
5874 stop_func_sal
= find_pc_line (stop_pc
, 0);
5876 /* OK, we're just going to keep stepping here. */
5877 if (stop_func_sal
.pc
== stop_pc
)
5879 /* We're there already. Just stop stepping now. */
5880 end_stepping_range (ecs
);
5884 /* Else just reset the step range and keep going.
5885 No step-resume breakpoint, they don't work for
5886 epilogues, which can have multiple entry paths. */
5887 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5888 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5894 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5895 This is used to both functions and to skip over code. */
5898 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5899 struct symtab_and_line sr_sal
,
5900 struct frame_id sr_id
,
5901 enum bptype sr_type
)
5903 /* There should never be more than one step-resume or longjmp-resume
5904 breakpoint per thread, so we should never be setting a new
5905 step_resume_breakpoint when one is already active. */
5906 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5907 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5910 fprintf_unfiltered (gdb_stdlog
,
5911 "infrun: inserting step-resume breakpoint at %s\n",
5912 paddress (gdbarch
, sr_sal
.pc
));
5914 inferior_thread ()->control
.step_resume_breakpoint
5915 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5919 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5920 struct symtab_and_line sr_sal
,
5921 struct frame_id sr_id
)
5923 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5928 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5929 This is used to skip a potential signal handler.
5931 This is called with the interrupted function's frame. The signal
5932 handler, when it returns, will resume the interrupted function at
5936 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5938 struct symtab_and_line sr_sal
;
5939 struct gdbarch
*gdbarch
;
5941 gdb_assert (return_frame
!= NULL
);
5942 init_sal (&sr_sal
); /* initialize to zeros */
5944 gdbarch
= get_frame_arch (return_frame
);
5945 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5946 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5947 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5949 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5950 get_stack_frame_id (return_frame
),
5954 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5955 is used to skip a function after stepping into it (for "next" or if
5956 the called function has no debugging information).
5958 The current function has almost always been reached by single
5959 stepping a call or return instruction. NEXT_FRAME belongs to the
5960 current function, and the breakpoint will be set at the caller's
5963 This is a separate function rather than reusing
5964 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5965 get_prev_frame, which may stop prematurely (see the implementation
5966 of frame_unwind_caller_id for an example). */
5969 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5971 struct symtab_and_line sr_sal
;
5972 struct gdbarch
*gdbarch
;
5974 /* We shouldn't have gotten here if we don't know where the call site
5976 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5978 init_sal (&sr_sal
); /* initialize to zeros */
5980 gdbarch
= frame_unwind_caller_arch (next_frame
);
5981 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5982 frame_unwind_caller_pc (next_frame
));
5983 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5984 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5986 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5987 frame_unwind_caller_id (next_frame
));
5990 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5991 new breakpoint at the target of a jmp_buf. The handling of
5992 longjmp-resume uses the same mechanisms used for handling
5993 "step-resume" breakpoints. */
5996 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5998 /* There should never be more than one longjmp-resume breakpoint per
5999 thread, so we should never be setting a new
6000 longjmp_resume_breakpoint when one is already active. */
6001 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
6004 fprintf_unfiltered (gdb_stdlog
,
6005 "infrun: inserting longjmp-resume breakpoint at %s\n",
6006 paddress (gdbarch
, pc
));
6008 inferior_thread ()->control
.exception_resume_breakpoint
=
6009 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
6012 /* Insert an exception resume breakpoint. TP is the thread throwing
6013 the exception. The block B is the block of the unwinder debug hook
6014 function. FRAME is the frame corresponding to the call to this
6015 function. SYM is the symbol of the function argument holding the
6016 target PC of the exception. */
6019 insert_exception_resume_breakpoint (struct thread_info
*tp
,
6020 const struct block
*b
,
6021 struct frame_info
*frame
,
6026 struct symbol
*vsym
;
6027 struct value
*value
;
6029 struct breakpoint
*bp
;
6031 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
6032 value
= read_var_value (vsym
, frame
);
6033 /* If the value was optimized out, revert to the old behavior. */
6034 if (! value_optimized_out (value
))
6036 handler
= value_as_address (value
);
6039 fprintf_unfiltered (gdb_stdlog
,
6040 "infrun: exception resume at %lx\n",
6041 (unsigned long) handler
);
6043 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
6044 handler
, bp_exception_resume
);
6046 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
6049 bp
->thread
= tp
->num
;
6050 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
6053 CATCH (e
, RETURN_MASK_ERROR
)
6055 /* We want to ignore errors here. */
6060 /* A helper for check_exception_resume that sets an
6061 exception-breakpoint based on a SystemTap probe. */
6064 insert_exception_resume_from_probe (struct thread_info
*tp
,
6065 const struct bound_probe
*probe
,
6066 struct frame_info
*frame
)
6068 struct value
*arg_value
;
6070 struct breakpoint
*bp
;
6072 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
6076 handler
= value_as_address (arg_value
);
6079 fprintf_unfiltered (gdb_stdlog
,
6080 "infrun: exception resume at %s\n",
6081 paddress (get_objfile_arch (probe
->objfile
),
6084 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
6085 handler
, bp_exception_resume
);
6086 bp
->thread
= tp
->num
;
6087 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
6090 /* This is called when an exception has been intercepted. Check to
6091 see whether the exception's destination is of interest, and if so,
6092 set an exception resume breakpoint there. */
6095 check_exception_resume (struct execution_control_state
*ecs
,
6096 struct frame_info
*frame
)
6098 struct bound_probe probe
;
6099 struct symbol
*func
;
6101 /* First see if this exception unwinding breakpoint was set via a
6102 SystemTap probe point. If so, the probe has two arguments: the
6103 CFA and the HANDLER. We ignore the CFA, extract the handler, and
6104 set a breakpoint there. */
6105 probe
= find_probe_by_pc (get_frame_pc (frame
));
6108 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
6112 func
= get_frame_function (frame
);
6118 const struct block
*b
;
6119 struct block_iterator iter
;
6123 /* The exception breakpoint is a thread-specific breakpoint on
6124 the unwinder's debug hook, declared as:
6126 void _Unwind_DebugHook (void *cfa, void *handler);
6128 The CFA argument indicates the frame to which control is
6129 about to be transferred. HANDLER is the destination PC.
6131 We ignore the CFA and set a temporary breakpoint at HANDLER.
6132 This is not extremely efficient but it avoids issues in gdb
6133 with computing the DWARF CFA, and it also works even in weird
6134 cases such as throwing an exception from inside a signal
6137 b
= SYMBOL_BLOCK_VALUE (func
);
6138 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
6140 if (!SYMBOL_IS_ARGUMENT (sym
))
6147 insert_exception_resume_breakpoint (ecs
->event_thread
,
6153 CATCH (e
, RETURN_MASK_ERROR
)
6160 stop_waiting (struct execution_control_state
*ecs
)
6163 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
6165 clear_step_over_info ();
6167 /* Let callers know we don't want to wait for the inferior anymore. */
6168 ecs
->wait_some_more
= 0;
6171 /* Called when we should continue running the inferior, because the
6172 current event doesn't cause a user visible stop. This does the
6173 resuming part; waiting for the next event is done elsewhere. */
6176 keep_going (struct execution_control_state
*ecs
)
6178 /* Make sure normal_stop is called if we get a QUIT handled before
6180 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
6182 /* Save the pc before execution, to compare with pc after stop. */
6183 ecs
->event_thread
->prev_pc
6184 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
6186 if (ecs
->event_thread
->control
.trap_expected
6187 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6189 /* We haven't yet gotten our trap, and either: intercepted a
6190 non-signal event (e.g., a fork); or took a signal which we
6191 are supposed to pass through to the inferior. Simply
6193 discard_cleanups (old_cleanups
);
6194 resume (currently_stepping (ecs
->event_thread
),
6195 ecs
->event_thread
->suspend
.stop_signal
);
6199 struct regcache
*regcache
= get_current_regcache ();
6203 /* Either the trap was not expected, but we are continuing
6204 anyway (if we got a signal, the user asked it be passed to
6207 We got our expected trap, but decided we should resume from
6210 We're going to run this baby now!
6212 Note that insert_breakpoints won't try to re-insert
6213 already inserted breakpoints. Therefore, we don't
6214 care if breakpoints were already inserted, or not. */
6216 /* If we need to step over a breakpoint, and we're not using
6217 displaced stepping to do so, insert all breakpoints
6218 (watchpoints, etc.) but the one we're stepping over, step one
6219 instruction, and then re-insert the breakpoint when that step
6222 remove_bp
= (ecs
->hit_singlestep_breakpoint
6223 || thread_still_needs_step_over (ecs
->event_thread
));
6224 remove_wps
= (ecs
->event_thread
->stepping_over_watchpoint
6225 && !target_have_steppable_watchpoint
);
6227 if (remove_bp
&& !use_displaced_stepping (get_regcache_arch (regcache
)))
6229 set_step_over_info (get_regcache_aspace (regcache
),
6230 regcache_read_pc (regcache
), remove_wps
);
6232 else if (remove_wps
)
6233 set_step_over_info (NULL
, 0, remove_wps
);
6235 clear_step_over_info ();
6237 /* Stop stepping if inserting breakpoints fails. */
6240 insert_breakpoints ();
6242 CATCH (e
, RETURN_MASK_ERROR
)
6244 exception_print (gdb_stderr
, e
);
6250 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
6252 /* Do not deliver GDB_SIGNAL_TRAP (except when the user
6253 explicitly specifies that such a signal should be delivered
6254 to the target program). Typically, that would occur when a
6255 user is debugging a target monitor on a simulator: the target
6256 monitor sets a breakpoint; the simulator encounters this
6257 breakpoint and halts the simulation handing control to GDB;
6258 GDB, noting that the stop address doesn't map to any known
6259 breakpoint, returns control back to the simulator; the
6260 simulator then delivers the hardware equivalent of a
6261 GDB_SIGNAL_TRAP to the program being debugged. */
6262 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6263 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6264 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6266 discard_cleanups (old_cleanups
);
6267 resume (currently_stepping (ecs
->event_thread
),
6268 ecs
->event_thread
->suspend
.stop_signal
);
6271 prepare_to_wait (ecs
);
6274 /* This function normally comes after a resume, before
6275 handle_inferior_event exits. It takes care of any last bits of
6276 housekeeping, and sets the all-important wait_some_more flag. */
6279 prepare_to_wait (struct execution_control_state
*ecs
)
6282 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
6284 /* This is the old end of the while loop. Let everybody know we
6285 want to wait for the inferior some more and get called again
6287 ecs
->wait_some_more
= 1;
6290 /* We are done with the step range of a step/next/si/ni command.
6291 Called once for each n of a "step n" operation. */
6294 end_stepping_range (struct execution_control_state
*ecs
)
6296 ecs
->event_thread
->control
.stop_step
= 1;
6300 /* Several print_*_reason functions to print why the inferior has stopped.
6301 We always print something when the inferior exits, or receives a signal.
6302 The rest of the cases are dealt with later on in normal_stop and
6303 print_it_typical. Ideally there should be a call to one of these
6304 print_*_reason functions functions from handle_inferior_event each time
6305 stop_waiting is called.
6307 Note that we don't call these directly, instead we delegate that to
6308 the interpreters, through observers. Interpreters then call these
6309 with whatever uiout is right. */
6312 print_end_stepping_range_reason (struct ui_out
*uiout
)
6314 /* For CLI-like interpreters, print nothing. */
6316 if (ui_out_is_mi_like_p (uiout
))
6318 ui_out_field_string (uiout
, "reason",
6319 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
6324 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6326 annotate_signalled ();
6327 if (ui_out_is_mi_like_p (uiout
))
6329 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
6330 ui_out_text (uiout
, "\nProgram terminated with signal ");
6331 annotate_signal_name ();
6332 ui_out_field_string (uiout
, "signal-name",
6333 gdb_signal_to_name (siggnal
));
6334 annotate_signal_name_end ();
6335 ui_out_text (uiout
, ", ");
6336 annotate_signal_string ();
6337 ui_out_field_string (uiout
, "signal-meaning",
6338 gdb_signal_to_string (siggnal
));
6339 annotate_signal_string_end ();
6340 ui_out_text (uiout
, ".\n");
6341 ui_out_text (uiout
, "The program no longer exists.\n");
6345 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
6347 struct inferior
*inf
= current_inferior ();
6348 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
6350 annotate_exited (exitstatus
);
6353 if (ui_out_is_mi_like_p (uiout
))
6354 ui_out_field_string (uiout
, "reason",
6355 async_reason_lookup (EXEC_ASYNC_EXITED
));
6356 ui_out_text (uiout
, "[Inferior ");
6357 ui_out_text (uiout
, plongest (inf
->num
));
6358 ui_out_text (uiout
, " (");
6359 ui_out_text (uiout
, pidstr
);
6360 ui_out_text (uiout
, ") exited with code ");
6361 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
6362 ui_out_text (uiout
, "]\n");
6366 if (ui_out_is_mi_like_p (uiout
))
6368 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
6369 ui_out_text (uiout
, "[Inferior ");
6370 ui_out_text (uiout
, plongest (inf
->num
));
6371 ui_out_text (uiout
, " (");
6372 ui_out_text (uiout
, pidstr
);
6373 ui_out_text (uiout
, ") exited normally]\n");
6378 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6382 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
6384 struct thread_info
*t
= inferior_thread ();
6386 ui_out_text (uiout
, "\n[");
6387 ui_out_field_string (uiout
, "thread-name",
6388 target_pid_to_str (t
->ptid
));
6389 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
6390 ui_out_text (uiout
, " stopped");
6394 ui_out_text (uiout
, "\nProgram received signal ");
6395 annotate_signal_name ();
6396 if (ui_out_is_mi_like_p (uiout
))
6398 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
6399 ui_out_field_string (uiout
, "signal-name",
6400 gdb_signal_to_name (siggnal
));
6401 annotate_signal_name_end ();
6402 ui_out_text (uiout
, ", ");
6403 annotate_signal_string ();
6404 ui_out_field_string (uiout
, "signal-meaning",
6405 gdb_signal_to_string (siggnal
));
6406 annotate_signal_string_end ();
6408 ui_out_text (uiout
, ".\n");
6412 print_no_history_reason (struct ui_out
*uiout
)
6414 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
6417 /* Print current location without a level number, if we have changed
6418 functions or hit a breakpoint. Print source line if we have one.
6419 bpstat_print contains the logic deciding in detail what to print,
6420 based on the event(s) that just occurred. */
6423 print_stop_event (struct target_waitstatus
*ws
)
6427 int do_frame_printing
= 1;
6428 struct thread_info
*tp
= inferior_thread ();
6430 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
6434 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
6435 should) carry around the function and does (or should) use
6436 that when doing a frame comparison. */
6437 if (tp
->control
.stop_step
6438 && frame_id_eq (tp
->control
.step_frame_id
,
6439 get_frame_id (get_current_frame ()))
6440 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
6442 /* Finished step, just print source line. */
6443 source_flag
= SRC_LINE
;
6447 /* Print location and source line. */
6448 source_flag
= SRC_AND_LOC
;
6451 case PRINT_SRC_AND_LOC
:
6452 /* Print location and source line. */
6453 source_flag
= SRC_AND_LOC
;
6455 case PRINT_SRC_ONLY
:
6456 source_flag
= SRC_LINE
;
6459 /* Something bogus. */
6460 source_flag
= SRC_LINE
;
6461 do_frame_printing
= 0;
6464 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6467 /* The behavior of this routine with respect to the source
6469 SRC_LINE: Print only source line
6470 LOCATION: Print only location
6471 SRC_AND_LOC: Print location and source line. */
6472 if (do_frame_printing
)
6473 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
6475 /* Display the auto-display expressions. */
6479 /* Here to return control to GDB when the inferior stops for real.
6480 Print appropriate messages, remove breakpoints, give terminal our modes.
6482 STOP_PRINT_FRAME nonzero means print the executing frame
6483 (pc, function, args, file, line number and line text).
6484 BREAKPOINTS_FAILED nonzero means stop was due to error
6485 attempting to insert breakpoints. */
6490 struct target_waitstatus last
;
6492 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
6494 get_last_target_status (&last_ptid
, &last
);
6496 /* If an exception is thrown from this point on, make sure to
6497 propagate GDB's knowledge of the executing state to the
6498 frontend/user running state. A QUIT is an easy exception to see
6499 here, so do this before any filtered output. */
6501 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
6502 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6503 && last
.kind
!= TARGET_WAITKIND_EXITED
6504 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6505 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
6507 /* As we're presenting a stop, and potentially removing breakpoints,
6508 update the thread list so we can tell whether there are threads
6509 running on the target. With target remote, for example, we can
6510 only learn about new threads when we explicitly update the thread
6511 list. Do this before notifying the interpreters about signal
6512 stops, end of stepping ranges, etc., so that the "new thread"
6513 output is emitted before e.g., "Program received signal FOO",
6514 instead of after. */
6515 update_thread_list ();
6517 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
6518 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
6520 /* As with the notification of thread events, we want to delay
6521 notifying the user that we've switched thread context until
6522 the inferior actually stops.
6524 There's no point in saying anything if the inferior has exited.
6525 Note that SIGNALLED here means "exited with a signal", not
6526 "received a signal".
6528 Also skip saying anything in non-stop mode. In that mode, as we
6529 don't want GDB to switch threads behind the user's back, to avoid
6530 races where the user is typing a command to apply to thread x,
6531 but GDB switches to thread y before the user finishes entering
6532 the command, fetch_inferior_event installs a cleanup to restore
6533 the current thread back to the thread the user had selected right
6534 after this event is handled, so we're not really switching, only
6535 informing of a stop. */
6537 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
6538 && target_has_execution
6539 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6540 && last
.kind
!= TARGET_WAITKIND_EXITED
6541 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6543 target_terminal_ours_for_output ();
6544 printf_filtered (_("[Switching to %s]\n"),
6545 target_pid_to_str (inferior_ptid
));
6546 annotate_thread_changed ();
6547 previous_inferior_ptid
= inferior_ptid
;
6550 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
6552 gdb_assert (sync_execution
|| !target_can_async_p ());
6554 target_terminal_ours_for_output ();
6555 printf_filtered (_("No unwaited-for children left.\n"));
6558 /* Note: this depends on the update_thread_list call above. */
6559 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
6561 if (remove_breakpoints ())
6563 target_terminal_ours_for_output ();
6564 printf_filtered (_("Cannot remove breakpoints because "
6565 "program is no longer writable.\nFurther "
6566 "execution is probably impossible.\n"));
6570 /* If an auto-display called a function and that got a signal,
6571 delete that auto-display to avoid an infinite recursion. */
6573 if (stopped_by_random_signal
)
6574 disable_current_display ();
6576 /* Notify observers if we finished a "step"-like command, etc. */
6577 if (target_has_execution
6578 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6579 && last
.kind
!= TARGET_WAITKIND_EXITED
6580 && inferior_thread ()->control
.stop_step
)
6582 /* But not if in the middle of doing a "step n" operation for
6584 if (inferior_thread ()->step_multi
)
6587 observer_notify_end_stepping_range ();
6590 target_terminal_ours ();
6591 async_enable_stdin ();
6593 /* Set the current source location. This will also happen if we
6594 display the frame below, but the current SAL will be incorrect
6595 during a user hook-stop function. */
6596 if (has_stack_frames () && !stop_stack_dummy
)
6597 set_current_sal_from_frame (get_current_frame ());
6599 /* Let the user/frontend see the threads as stopped, but do nothing
6600 if the thread was running an infcall. We may be e.g., evaluating
6601 a breakpoint condition. In that case, the thread had state
6602 THREAD_RUNNING before the infcall, and shall remain set to
6603 running, all without informing the user/frontend about state
6604 transition changes. If this is actually a call command, then the
6605 thread was originally already stopped, so there's no state to
6607 if (target_has_execution
&& inferior_thread ()->control
.in_infcall
)
6608 discard_cleanups (old_chain
);
6610 do_cleanups (old_chain
);
6612 /* Look up the hook_stop and run it (CLI internally handles problem
6613 of stop_command's pre-hook not existing). */
6615 catch_errors (hook_stop_stub
, stop_command
,
6616 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6618 if (!has_stack_frames ())
6621 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6622 || last
.kind
== TARGET_WAITKIND_EXITED
)
6625 /* Select innermost stack frame - i.e., current frame is frame 0,
6626 and current location is based on that.
6627 Don't do this on return from a stack dummy routine,
6628 or if the program has exited. */
6630 if (!stop_stack_dummy
)
6632 select_frame (get_current_frame ());
6634 /* If --batch-silent is enabled then there's no need to print the current
6635 source location, and to try risks causing an error message about
6636 missing source files. */
6637 if (stop_print_frame
&& !batch_silent
)
6638 print_stop_event (&last
);
6641 /* Save the function value return registers, if we care.
6642 We might be about to restore their previous contents. */
6643 if (inferior_thread ()->control
.proceed_to_finish
6644 && execution_direction
!= EXEC_REVERSE
)
6646 /* This should not be necessary. */
6648 regcache_xfree (stop_registers
);
6650 /* NB: The copy goes through to the target picking up the value of
6651 all the registers. */
6652 stop_registers
= regcache_dup (get_current_regcache ());
6655 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6657 /* Pop the empty frame that contains the stack dummy.
6658 This also restores inferior state prior to the call
6659 (struct infcall_suspend_state). */
6660 struct frame_info
*frame
= get_current_frame ();
6662 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6664 /* frame_pop() calls reinit_frame_cache as the last thing it
6665 does which means there's currently no selected frame. We
6666 don't need to re-establish a selected frame if the dummy call
6667 returns normally, that will be done by
6668 restore_infcall_control_state. However, we do have to handle
6669 the case where the dummy call is returning after being
6670 stopped (e.g. the dummy call previously hit a breakpoint).
6671 We can't know which case we have so just always re-establish
6672 a selected frame here. */
6673 select_frame (get_current_frame ());
6677 annotate_stopped ();
6679 /* Suppress the stop observer if we're in the middle of:
6681 - a step n (n > 1), as there still more steps to be done.
6683 - a "finish" command, as the observer will be called in
6684 finish_command_continuation, so it can include the inferior
6685 function's return value.
6687 - calling an inferior function, as we pretend we inferior didn't
6688 run at all. The return value of the call is handled by the
6689 expression evaluator, through call_function_by_hand. */
6691 if (!target_has_execution
6692 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6693 || last
.kind
== TARGET_WAITKIND_EXITED
6694 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6695 || (!(inferior_thread ()->step_multi
6696 && inferior_thread ()->control
.stop_step
)
6697 && !(inferior_thread ()->control
.stop_bpstat
6698 && inferior_thread ()->control
.proceed_to_finish
)
6699 && !inferior_thread ()->control
.in_infcall
))
6701 if (!ptid_equal (inferior_ptid
, null_ptid
))
6702 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6705 observer_notify_normal_stop (NULL
, stop_print_frame
);
6708 if (target_has_execution
)
6710 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6711 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6712 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6713 Delete any breakpoint that is to be deleted at the next stop. */
6714 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6717 /* Try to get rid of automatically added inferiors that are no
6718 longer needed. Keeping those around slows down things linearly.
6719 Note that this never removes the current inferior. */
6724 hook_stop_stub (void *cmd
)
6726 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6731 signal_stop_state (int signo
)
6733 return signal_stop
[signo
];
6737 signal_print_state (int signo
)
6739 return signal_print
[signo
];
6743 signal_pass_state (int signo
)
6745 return signal_program
[signo
];
6749 signal_cache_update (int signo
)
6753 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6754 signal_cache_update (signo
);
6759 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6760 && signal_print
[signo
] == 0
6761 && signal_program
[signo
] == 1
6762 && signal_catch
[signo
] == 0);
6766 signal_stop_update (int signo
, int state
)
6768 int ret
= signal_stop
[signo
];
6770 signal_stop
[signo
] = state
;
6771 signal_cache_update (signo
);
6776 signal_print_update (int signo
, int state
)
6778 int ret
= signal_print
[signo
];
6780 signal_print
[signo
] = state
;
6781 signal_cache_update (signo
);
6786 signal_pass_update (int signo
, int state
)
6788 int ret
= signal_program
[signo
];
6790 signal_program
[signo
] = state
;
6791 signal_cache_update (signo
);
6795 /* Update the global 'signal_catch' from INFO and notify the
6799 signal_catch_update (const unsigned int *info
)
6803 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
6804 signal_catch
[i
] = info
[i
] > 0;
6805 signal_cache_update (-1);
6806 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6810 sig_print_header (void)
6812 printf_filtered (_("Signal Stop\tPrint\tPass "
6813 "to program\tDescription\n"));
6817 sig_print_info (enum gdb_signal oursig
)
6819 const char *name
= gdb_signal_to_name (oursig
);
6820 int name_padding
= 13 - strlen (name
);
6822 if (name_padding
<= 0)
6825 printf_filtered ("%s", name
);
6826 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6827 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6828 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6829 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6830 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6833 /* Specify how various signals in the inferior should be handled. */
6836 handle_command (char *args
, int from_tty
)
6839 int digits
, wordlen
;
6840 int sigfirst
, signum
, siglast
;
6841 enum gdb_signal oursig
;
6844 unsigned char *sigs
;
6845 struct cleanup
*old_chain
;
6849 error_no_arg (_("signal to handle"));
6852 /* Allocate and zero an array of flags for which signals to handle. */
6854 nsigs
= (int) GDB_SIGNAL_LAST
;
6855 sigs
= (unsigned char *) alloca (nsigs
);
6856 memset (sigs
, 0, nsigs
);
6858 /* Break the command line up into args. */
6860 argv
= gdb_buildargv (args
);
6861 old_chain
= make_cleanup_freeargv (argv
);
6863 /* Walk through the args, looking for signal oursigs, signal names, and
6864 actions. Signal numbers and signal names may be interspersed with
6865 actions, with the actions being performed for all signals cumulatively
6866 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6868 while (*argv
!= NULL
)
6870 wordlen
= strlen (*argv
);
6871 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6875 sigfirst
= siglast
= -1;
6877 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6879 /* Apply action to all signals except those used by the
6880 debugger. Silently skip those. */
6883 siglast
= nsigs
- 1;
6885 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6887 SET_SIGS (nsigs
, sigs
, signal_stop
);
6888 SET_SIGS (nsigs
, sigs
, signal_print
);
6890 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6892 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6894 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6896 SET_SIGS (nsigs
, sigs
, signal_print
);
6898 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6900 SET_SIGS (nsigs
, sigs
, signal_program
);
6902 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6904 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6906 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6908 SET_SIGS (nsigs
, sigs
, signal_program
);
6910 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6912 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6913 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6915 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6917 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6919 else if (digits
> 0)
6921 /* It is numeric. The numeric signal refers to our own
6922 internal signal numbering from target.h, not to host/target
6923 signal number. This is a feature; users really should be
6924 using symbolic names anyway, and the common ones like
6925 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6927 sigfirst
= siglast
= (int)
6928 gdb_signal_from_command (atoi (*argv
));
6929 if ((*argv
)[digits
] == '-')
6932 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6934 if (sigfirst
> siglast
)
6936 /* Bet he didn't figure we'd think of this case... */
6944 oursig
= gdb_signal_from_name (*argv
);
6945 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6947 sigfirst
= siglast
= (int) oursig
;
6951 /* Not a number and not a recognized flag word => complain. */
6952 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6956 /* If any signal numbers or symbol names were found, set flags for
6957 which signals to apply actions to. */
6959 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6961 switch ((enum gdb_signal
) signum
)
6963 case GDB_SIGNAL_TRAP
:
6964 case GDB_SIGNAL_INT
:
6965 if (!allsigs
&& !sigs
[signum
])
6967 if (query (_("%s is used by the debugger.\n\
6968 Are you sure you want to change it? "),
6969 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6975 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6976 gdb_flush (gdb_stdout
);
6981 case GDB_SIGNAL_DEFAULT
:
6982 case GDB_SIGNAL_UNKNOWN
:
6983 /* Make sure that "all" doesn't print these. */
6994 for (signum
= 0; signum
< nsigs
; signum
++)
6997 signal_cache_update (-1);
6998 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6999 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
7003 /* Show the results. */
7004 sig_print_header ();
7005 for (; signum
< nsigs
; signum
++)
7007 sig_print_info (signum
);
7013 do_cleanups (old_chain
);
7016 /* Complete the "handle" command. */
7018 static VEC (char_ptr
) *
7019 handle_completer (struct cmd_list_element
*ignore
,
7020 const char *text
, const char *word
)
7022 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
7023 static const char * const keywords
[] =
7037 vec_signals
= signal_completer (ignore
, text
, word
);
7038 vec_keywords
= complete_on_enum (keywords
, word
, word
);
7040 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
7041 VEC_free (char_ptr
, vec_signals
);
7042 VEC_free (char_ptr
, vec_keywords
);
7047 xdb_handle_command (char *args
, int from_tty
)
7050 struct cleanup
*old_chain
;
7053 error_no_arg (_("xdb command"));
7055 /* Break the command line up into args. */
7057 argv
= gdb_buildargv (args
);
7058 old_chain
= make_cleanup_freeargv (argv
);
7059 if (argv
[1] != (char *) NULL
)
7064 bufLen
= strlen (argv
[0]) + 20;
7065 argBuf
= (char *) xmalloc (bufLen
);
7069 enum gdb_signal oursig
;
7071 oursig
= gdb_signal_from_name (argv
[0]);
7072 memset (argBuf
, 0, bufLen
);
7073 if (strcmp (argv
[1], "Q") == 0)
7074 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
7077 if (strcmp (argv
[1], "s") == 0)
7079 if (!signal_stop
[oursig
])
7080 sprintf (argBuf
, "%s %s", argv
[0], "stop");
7082 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
7084 else if (strcmp (argv
[1], "i") == 0)
7086 if (!signal_program
[oursig
])
7087 sprintf (argBuf
, "%s %s", argv
[0], "pass");
7089 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
7091 else if (strcmp (argv
[1], "r") == 0)
7093 if (!signal_print
[oursig
])
7094 sprintf (argBuf
, "%s %s", argv
[0], "print");
7096 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
7102 handle_command (argBuf
, from_tty
);
7104 printf_filtered (_("Invalid signal handling flag.\n"));
7109 do_cleanups (old_chain
);
7113 gdb_signal_from_command (int num
)
7115 if (num
>= 1 && num
<= 15)
7116 return (enum gdb_signal
) num
;
7117 error (_("Only signals 1-15 are valid as numeric signals.\n\
7118 Use \"info signals\" for a list of symbolic signals."));
7121 /* Print current contents of the tables set by the handle command.
7122 It is possible we should just be printing signals actually used
7123 by the current target (but for things to work right when switching
7124 targets, all signals should be in the signal tables). */
7127 signals_info (char *signum_exp
, int from_tty
)
7129 enum gdb_signal oursig
;
7131 sig_print_header ();
7135 /* First see if this is a symbol name. */
7136 oursig
= gdb_signal_from_name (signum_exp
);
7137 if (oursig
== GDB_SIGNAL_UNKNOWN
)
7139 /* No, try numeric. */
7141 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
7143 sig_print_info (oursig
);
7147 printf_filtered ("\n");
7148 /* These ugly casts brought to you by the native VAX compiler. */
7149 for (oursig
= GDB_SIGNAL_FIRST
;
7150 (int) oursig
< (int) GDB_SIGNAL_LAST
;
7151 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
7155 if (oursig
!= GDB_SIGNAL_UNKNOWN
7156 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
7157 sig_print_info (oursig
);
7160 printf_filtered (_("\nUse the \"handle\" command "
7161 "to change these tables.\n"));
7164 /* Check if it makes sense to read $_siginfo from the current thread
7165 at this point. If not, throw an error. */
7168 validate_siginfo_access (void)
7170 /* No current inferior, no siginfo. */
7171 if (ptid_equal (inferior_ptid
, null_ptid
))
7172 error (_("No thread selected."));
7174 /* Don't try to read from a dead thread. */
7175 if (is_exited (inferior_ptid
))
7176 error (_("The current thread has terminated"));
7178 /* ... or from a spinning thread. */
7179 if (is_running (inferior_ptid
))
7180 error (_("Selected thread is running."));
7183 /* The $_siginfo convenience variable is a bit special. We don't know
7184 for sure the type of the value until we actually have a chance to
7185 fetch the data. The type can change depending on gdbarch, so it is
7186 also dependent on which thread you have selected.
7188 1. making $_siginfo be an internalvar that creates a new value on
7191 2. making the value of $_siginfo be an lval_computed value. */
7193 /* This function implements the lval_computed support for reading a
7197 siginfo_value_read (struct value
*v
)
7199 LONGEST transferred
;
7201 validate_siginfo_access ();
7204 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
7206 value_contents_all_raw (v
),
7208 TYPE_LENGTH (value_type (v
)));
7210 if (transferred
!= TYPE_LENGTH (value_type (v
)))
7211 error (_("Unable to read siginfo"));
7214 /* This function implements the lval_computed support for writing a
7218 siginfo_value_write (struct value
*v
, struct value
*fromval
)
7220 LONGEST transferred
;
7222 validate_siginfo_access ();
7224 transferred
= target_write (¤t_target
,
7225 TARGET_OBJECT_SIGNAL_INFO
,
7227 value_contents_all_raw (fromval
),
7229 TYPE_LENGTH (value_type (fromval
)));
7231 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
7232 error (_("Unable to write siginfo"));
7235 static const struct lval_funcs siginfo_value_funcs
=
7241 /* Return a new value with the correct type for the siginfo object of
7242 the current thread using architecture GDBARCH. Return a void value
7243 if there's no object available. */
7245 static struct value
*
7246 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
7249 if (target_has_stack
7250 && !ptid_equal (inferior_ptid
, null_ptid
)
7251 && gdbarch_get_siginfo_type_p (gdbarch
))
7253 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7255 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
7258 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
7262 /* infcall_suspend_state contains state about the program itself like its
7263 registers and any signal it received when it last stopped.
7264 This state must be restored regardless of how the inferior function call
7265 ends (either successfully, or after it hits a breakpoint or signal)
7266 if the program is to properly continue where it left off. */
7268 struct infcall_suspend_state
7270 struct thread_suspend_state thread_suspend
;
7271 #if 0 /* Currently unused and empty structures are not valid C. */
7272 struct inferior_suspend_state inferior_suspend
;
7277 struct regcache
*registers
;
7279 /* Format of SIGINFO_DATA or NULL if it is not present. */
7280 struct gdbarch
*siginfo_gdbarch
;
7282 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
7283 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
7284 content would be invalid. */
7285 gdb_byte
*siginfo_data
;
7288 struct infcall_suspend_state
*
7289 save_infcall_suspend_state (void)
7291 struct infcall_suspend_state
*inf_state
;
7292 struct thread_info
*tp
= inferior_thread ();
7294 struct inferior
*inf
= current_inferior ();
7296 struct regcache
*regcache
= get_current_regcache ();
7297 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7298 gdb_byte
*siginfo_data
= NULL
;
7300 if (gdbarch_get_siginfo_type_p (gdbarch
))
7302 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7303 size_t len
= TYPE_LENGTH (type
);
7304 struct cleanup
*back_to
;
7306 siginfo_data
= xmalloc (len
);
7307 back_to
= make_cleanup (xfree
, siginfo_data
);
7309 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7310 siginfo_data
, 0, len
) == len
)
7311 discard_cleanups (back_to
);
7314 /* Errors ignored. */
7315 do_cleanups (back_to
);
7316 siginfo_data
= NULL
;
7320 inf_state
= XCNEW (struct infcall_suspend_state
);
7324 inf_state
->siginfo_gdbarch
= gdbarch
;
7325 inf_state
->siginfo_data
= siginfo_data
;
7328 inf_state
->thread_suspend
= tp
->suspend
;
7329 #if 0 /* Currently unused and empty structures are not valid C. */
7330 inf_state
->inferior_suspend
= inf
->suspend
;
7333 /* run_inferior_call will not use the signal due to its `proceed' call with
7334 GDB_SIGNAL_0 anyway. */
7335 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7337 inf_state
->stop_pc
= stop_pc
;
7339 inf_state
->registers
= regcache_dup (regcache
);
7344 /* Restore inferior session state to INF_STATE. */
7347 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7349 struct thread_info
*tp
= inferior_thread ();
7351 struct inferior
*inf
= current_inferior ();
7353 struct regcache
*regcache
= get_current_regcache ();
7354 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7356 tp
->suspend
= inf_state
->thread_suspend
;
7357 #if 0 /* Currently unused and empty structures are not valid C. */
7358 inf
->suspend
= inf_state
->inferior_suspend
;
7361 stop_pc
= inf_state
->stop_pc
;
7363 if (inf_state
->siginfo_gdbarch
== gdbarch
)
7365 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7367 /* Errors ignored. */
7368 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7369 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
7372 /* The inferior can be gone if the user types "print exit(0)"
7373 (and perhaps other times). */
7374 if (target_has_execution
)
7375 /* NB: The register write goes through to the target. */
7376 regcache_cpy (regcache
, inf_state
->registers
);
7378 discard_infcall_suspend_state (inf_state
);
7382 do_restore_infcall_suspend_state_cleanup (void *state
)
7384 restore_infcall_suspend_state (state
);
7388 make_cleanup_restore_infcall_suspend_state
7389 (struct infcall_suspend_state
*inf_state
)
7391 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
7395 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7397 regcache_xfree (inf_state
->registers
);
7398 xfree (inf_state
->siginfo_data
);
7403 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
7405 return inf_state
->registers
;
7408 /* infcall_control_state contains state regarding gdb's control of the
7409 inferior itself like stepping control. It also contains session state like
7410 the user's currently selected frame. */
7412 struct infcall_control_state
7414 struct thread_control_state thread_control
;
7415 struct inferior_control_state inferior_control
;
7418 enum stop_stack_kind stop_stack_dummy
;
7419 int stopped_by_random_signal
;
7420 int stop_after_trap
;
7422 /* ID if the selected frame when the inferior function call was made. */
7423 struct frame_id selected_frame_id
;
7426 /* Save all of the information associated with the inferior<==>gdb
7429 struct infcall_control_state
*
7430 save_infcall_control_state (void)
7432 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
7433 struct thread_info
*tp
= inferior_thread ();
7434 struct inferior
*inf
= current_inferior ();
7436 inf_status
->thread_control
= tp
->control
;
7437 inf_status
->inferior_control
= inf
->control
;
7439 tp
->control
.step_resume_breakpoint
= NULL
;
7440 tp
->control
.exception_resume_breakpoint
= NULL
;
7442 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
7443 chain. If caller's caller is walking the chain, they'll be happier if we
7444 hand them back the original chain when restore_infcall_control_state is
7446 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
7449 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
7450 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
7451 inf_status
->stop_after_trap
= stop_after_trap
;
7453 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
7459 restore_selected_frame (void *args
)
7461 struct frame_id
*fid
= (struct frame_id
*) args
;
7462 struct frame_info
*frame
;
7464 frame
= frame_find_by_id (*fid
);
7466 /* If inf_status->selected_frame_id is NULL, there was no previously
7470 warning (_("Unable to restore previously selected frame."));
7474 select_frame (frame
);
7479 /* Restore inferior session state to INF_STATUS. */
7482 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
7484 struct thread_info
*tp
= inferior_thread ();
7485 struct inferior
*inf
= current_inferior ();
7487 if (tp
->control
.step_resume_breakpoint
)
7488 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
7490 if (tp
->control
.exception_resume_breakpoint
)
7491 tp
->control
.exception_resume_breakpoint
->disposition
7492 = disp_del_at_next_stop
;
7494 /* Handle the bpstat_copy of the chain. */
7495 bpstat_clear (&tp
->control
.stop_bpstat
);
7497 tp
->control
= inf_status
->thread_control
;
7498 inf
->control
= inf_status
->inferior_control
;
7501 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
7502 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
7503 stop_after_trap
= inf_status
->stop_after_trap
;
7505 if (target_has_stack
)
7507 /* The point of catch_errors is that if the stack is clobbered,
7508 walking the stack might encounter a garbage pointer and
7509 error() trying to dereference it. */
7511 (restore_selected_frame
, &inf_status
->selected_frame_id
,
7512 "Unable to restore previously selected frame:\n",
7513 RETURN_MASK_ERROR
) == 0)
7514 /* Error in restoring the selected frame. Select the innermost
7516 select_frame (get_current_frame ());
7523 do_restore_infcall_control_state_cleanup (void *sts
)
7525 restore_infcall_control_state (sts
);
7529 make_cleanup_restore_infcall_control_state
7530 (struct infcall_control_state
*inf_status
)
7532 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
7536 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
7538 if (inf_status
->thread_control
.step_resume_breakpoint
)
7539 inf_status
->thread_control
.step_resume_breakpoint
->disposition
7540 = disp_del_at_next_stop
;
7542 if (inf_status
->thread_control
.exception_resume_breakpoint
)
7543 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
7544 = disp_del_at_next_stop
;
7546 /* See save_infcall_control_state for info on stop_bpstat. */
7547 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
7552 /* restore_inferior_ptid() will be used by the cleanup machinery
7553 to restore the inferior_ptid value saved in a call to
7554 save_inferior_ptid(). */
7557 restore_inferior_ptid (void *arg
)
7559 ptid_t
*saved_ptid_ptr
= arg
;
7561 inferior_ptid
= *saved_ptid_ptr
;
7565 /* Save the value of inferior_ptid so that it may be restored by a
7566 later call to do_cleanups(). Returns the struct cleanup pointer
7567 needed for later doing the cleanup. */
7570 save_inferior_ptid (void)
7572 ptid_t
*saved_ptid_ptr
;
7574 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
7575 *saved_ptid_ptr
= inferior_ptid
;
7576 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
7582 clear_exit_convenience_vars (void)
7584 clear_internalvar (lookup_internalvar ("_exitsignal"));
7585 clear_internalvar (lookup_internalvar ("_exitcode"));
7589 /* User interface for reverse debugging:
7590 Set exec-direction / show exec-direction commands
7591 (returns error unless target implements to_set_exec_direction method). */
7593 int execution_direction
= EXEC_FORWARD
;
7594 static const char exec_forward
[] = "forward";
7595 static const char exec_reverse
[] = "reverse";
7596 static const char *exec_direction
= exec_forward
;
7597 static const char *const exec_direction_names
[] = {
7604 set_exec_direction_func (char *args
, int from_tty
,
7605 struct cmd_list_element
*cmd
)
7607 if (target_can_execute_reverse
)
7609 if (!strcmp (exec_direction
, exec_forward
))
7610 execution_direction
= EXEC_FORWARD
;
7611 else if (!strcmp (exec_direction
, exec_reverse
))
7612 execution_direction
= EXEC_REVERSE
;
7616 exec_direction
= exec_forward
;
7617 error (_("Target does not support this operation."));
7622 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7623 struct cmd_list_element
*cmd
, const char *value
)
7625 switch (execution_direction
) {
7627 fprintf_filtered (out
, _("Forward.\n"));
7630 fprintf_filtered (out
, _("Reverse.\n"));
7633 internal_error (__FILE__
, __LINE__
,
7634 _("bogus execution_direction value: %d"),
7635 (int) execution_direction
);
7640 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7641 struct cmd_list_element
*c
, const char *value
)
7643 fprintf_filtered (file
, _("Resuming the execution of threads "
7644 "of all processes is %s.\n"), value
);
7647 /* Implementation of `siginfo' variable. */
7649 static const struct internalvar_funcs siginfo_funcs
=
7657 _initialize_infrun (void)
7661 struct cmd_list_element
*c
;
7663 add_info ("signals", signals_info
, _("\
7664 What debugger does when program gets various signals.\n\
7665 Specify a signal as argument to print info on that signal only."));
7666 add_info_alias ("handle", "signals", 0);
7668 c
= add_com ("handle", class_run
, handle_command
, _("\
7669 Specify how to handle signals.\n\
7670 Usage: handle SIGNAL [ACTIONS]\n\
7671 Args are signals and actions to apply to those signals.\n\
7672 If no actions are specified, the current settings for the specified signals\n\
7673 will be displayed instead.\n\
7675 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7676 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7677 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7678 The special arg \"all\" is recognized to mean all signals except those\n\
7679 used by the debugger, typically SIGTRAP and SIGINT.\n\
7681 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7682 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7683 Stop means reenter debugger if this signal happens (implies print).\n\
7684 Print means print a message if this signal happens.\n\
7685 Pass means let program see this signal; otherwise program doesn't know.\n\
7686 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7687 Pass and Stop may be combined.\n\
7689 Multiple signals may be specified. Signal numbers and signal names\n\
7690 may be interspersed with actions, with the actions being performed for\n\
7691 all signals cumulatively specified."));
7692 set_cmd_completer (c
, handle_completer
);
7696 add_com ("lz", class_info
, signals_info
, _("\
7697 What debugger does when program gets various signals.\n\
7698 Specify a signal as argument to print info on that signal only."));
7699 add_com ("z", class_run
, xdb_handle_command
, _("\
7700 Specify how to handle a signal.\n\
7701 Args are signals and actions to apply to those signals.\n\
7702 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7703 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7704 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7705 The special arg \"all\" is recognized to mean all signals except those\n\
7706 used by the debugger, typically SIGTRAP and SIGINT.\n\
7707 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7708 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7709 nopass), \"Q\" (noprint)\n\
7710 Stop means reenter debugger if this signal happens (implies print).\n\
7711 Print means print a message if this signal happens.\n\
7712 Pass means let program see this signal; otherwise program doesn't know.\n\
7713 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7714 Pass and Stop may be combined."));
7718 stop_command
= add_cmd ("stop", class_obscure
,
7719 not_just_help_class_command
, _("\
7720 There is no `stop' command, but you can set a hook on `stop'.\n\
7721 This allows you to set a list of commands to be run each time execution\n\
7722 of the program stops."), &cmdlist
);
7724 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7725 Set inferior debugging."), _("\
7726 Show inferior debugging."), _("\
7727 When non-zero, inferior specific debugging is enabled."),
7730 &setdebuglist
, &showdebuglist
);
7732 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7733 &debug_displaced
, _("\
7734 Set displaced stepping debugging."), _("\
7735 Show displaced stepping debugging."), _("\
7736 When non-zero, displaced stepping specific debugging is enabled."),
7738 show_debug_displaced
,
7739 &setdebuglist
, &showdebuglist
);
7741 add_setshow_boolean_cmd ("non-stop", no_class
,
7743 Set whether gdb controls the inferior in non-stop mode."), _("\
7744 Show whether gdb controls the inferior in non-stop mode."), _("\
7745 When debugging a multi-threaded program and this setting is\n\
7746 off (the default, also called all-stop mode), when one thread stops\n\
7747 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7748 all other threads in the program while you interact with the thread of\n\
7749 interest. When you continue or step a thread, you can allow the other\n\
7750 threads to run, or have them remain stopped, but while you inspect any\n\
7751 thread's state, all threads stop.\n\
7753 In non-stop mode, when one thread stops, other threads can continue\n\
7754 to run freely. You'll be able to step each thread independently,\n\
7755 leave it stopped or free to run as needed."),
7761 numsigs
= (int) GDB_SIGNAL_LAST
;
7762 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7763 signal_print
= (unsigned char *)
7764 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7765 signal_program
= (unsigned char *)
7766 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7767 signal_catch
= (unsigned char *)
7768 xmalloc (sizeof (signal_catch
[0]) * numsigs
);
7769 signal_pass
= (unsigned char *)
7770 xmalloc (sizeof (signal_pass
[0]) * numsigs
);
7771 for (i
= 0; i
< numsigs
; i
++)
7774 signal_print
[i
] = 1;
7775 signal_program
[i
] = 1;
7776 signal_catch
[i
] = 0;
7779 /* Signals caused by debugger's own actions
7780 should not be given to the program afterwards. */
7781 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7782 signal_program
[GDB_SIGNAL_INT
] = 0;
7784 /* Signals that are not errors should not normally enter the debugger. */
7785 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7786 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7787 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7788 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7789 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7790 signal_print
[GDB_SIGNAL_PROF
] = 0;
7791 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7792 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7793 signal_stop
[GDB_SIGNAL_IO
] = 0;
7794 signal_print
[GDB_SIGNAL_IO
] = 0;
7795 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7796 signal_print
[GDB_SIGNAL_POLL
] = 0;
7797 signal_stop
[GDB_SIGNAL_URG
] = 0;
7798 signal_print
[GDB_SIGNAL_URG
] = 0;
7799 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7800 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7801 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7802 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7804 /* These signals are used internally by user-level thread
7805 implementations. (See signal(5) on Solaris.) Like the above
7806 signals, a healthy program receives and handles them as part of
7807 its normal operation. */
7808 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7809 signal_print
[GDB_SIGNAL_LWP
] = 0;
7810 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7811 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7812 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7813 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7815 /* Update cached state. */
7816 signal_cache_update (-1);
7818 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7819 &stop_on_solib_events
, _("\
7820 Set stopping for shared library events."), _("\
7821 Show stopping for shared library events."), _("\
7822 If nonzero, gdb will give control to the user when the dynamic linker\n\
7823 notifies gdb of shared library events. The most common event of interest\n\
7824 to the user would be loading/unloading of a new library."),
7825 set_stop_on_solib_events
,
7826 show_stop_on_solib_events
,
7827 &setlist
, &showlist
);
7829 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7830 follow_fork_mode_kind_names
,
7831 &follow_fork_mode_string
, _("\
7832 Set debugger response to a program call of fork or vfork."), _("\
7833 Show debugger response to a program call of fork or vfork."), _("\
7834 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7835 parent - the original process is debugged after a fork\n\
7836 child - the new process is debugged after a fork\n\
7837 The unfollowed process will continue to run.\n\
7838 By default, the debugger will follow the parent process."),
7840 show_follow_fork_mode_string
,
7841 &setlist
, &showlist
);
7843 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7844 follow_exec_mode_names
,
7845 &follow_exec_mode_string
, _("\
7846 Set debugger response to a program call of exec."), _("\
7847 Show debugger response to a program call of exec."), _("\
7848 An exec call replaces the program image of a process.\n\
7850 follow-exec-mode can be:\n\
7852 new - the debugger creates a new inferior and rebinds the process\n\
7853 to this new inferior. The program the process was running before\n\
7854 the exec call can be restarted afterwards by restarting the original\n\
7857 same - the debugger keeps the process bound to the same inferior.\n\
7858 The new executable image replaces the previous executable loaded in\n\
7859 the inferior. Restarting the inferior after the exec call restarts\n\
7860 the executable the process was running after the exec call.\n\
7862 By default, the debugger will use the same inferior."),
7864 show_follow_exec_mode_string
,
7865 &setlist
, &showlist
);
7867 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7868 scheduler_enums
, &scheduler_mode
, _("\
7869 Set mode for locking scheduler during execution."), _("\
7870 Show mode for locking scheduler during execution."), _("\
7871 off == no locking (threads may preempt at any time)\n\
7872 on == full locking (no thread except the current thread may run)\n\
7873 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
7874 In this mode, other threads may run during other commands."),
7875 set_schedlock_func
, /* traps on target vector */
7876 show_scheduler_mode
,
7877 &setlist
, &showlist
);
7879 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7880 Set mode for resuming threads of all processes."), _("\
7881 Show mode for resuming threads of all processes."), _("\
7882 When on, execution commands (such as 'continue' or 'next') resume all\n\
7883 threads of all processes. When off (which is the default), execution\n\
7884 commands only resume the threads of the current process. The set of\n\
7885 threads that are resumed is further refined by the scheduler-locking\n\
7886 mode (see help set scheduler-locking)."),
7888 show_schedule_multiple
,
7889 &setlist
, &showlist
);
7891 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7892 Set mode of the step operation."), _("\
7893 Show mode of the step operation."), _("\
7894 When set, doing a step over a function without debug line information\n\
7895 will stop at the first instruction of that function. Otherwise, the\n\
7896 function is skipped and the step command stops at a different source line."),
7898 show_step_stop_if_no_debug
,
7899 &setlist
, &showlist
);
7901 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7902 &can_use_displaced_stepping
, _("\
7903 Set debugger's willingness to use displaced stepping."), _("\
7904 Show debugger's willingness to use displaced stepping."), _("\
7905 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7906 supported by the target architecture. If off, gdb will not use displaced\n\
7907 stepping to step over breakpoints, even if such is supported by the target\n\
7908 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7909 if the target architecture supports it and non-stop mode is active, but will not\n\
7910 use it in all-stop mode (see help set non-stop)."),
7912 show_can_use_displaced_stepping
,
7913 &setlist
, &showlist
);
7915 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7916 &exec_direction
, _("Set direction of execution.\n\
7917 Options are 'forward' or 'reverse'."),
7918 _("Show direction of execution (forward/reverse)."),
7919 _("Tells gdb whether to execute forward or backward."),
7920 set_exec_direction_func
, show_exec_direction_func
,
7921 &setlist
, &showlist
);
7923 /* Set/show detach-on-fork: user-settable mode. */
7925 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7926 Set whether gdb will detach the child of a fork."), _("\
7927 Show whether gdb will detach the child of a fork."), _("\
7928 Tells gdb whether to detach the child of a fork."),
7929 NULL
, NULL
, &setlist
, &showlist
);
7931 /* Set/show disable address space randomization mode. */
7933 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7934 &disable_randomization
, _("\
7935 Set disabling of debuggee's virtual address space randomization."), _("\
7936 Show disabling of debuggee's virtual address space randomization."), _("\
7937 When this mode is on (which is the default), randomization of the virtual\n\
7938 address space is disabled. Standalone programs run with the randomization\n\
7939 enabled by default on some platforms."),
7940 &set_disable_randomization
,
7941 &show_disable_randomization
,
7942 &setlist
, &showlist
);
7944 /* ptid initializations */
7945 inferior_ptid
= null_ptid
;
7946 target_last_wait_ptid
= minus_one_ptid
;
7948 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7949 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7950 observer_attach_thread_exit (infrun_thread_thread_exit
);
7951 observer_attach_inferior_exit (infrun_inferior_exit
);
7953 /* Explicitly create without lookup, since that tries to create a
7954 value with a void typed value, and when we get here, gdbarch
7955 isn't initialized yet. At this point, we're quite sure there
7956 isn't another convenience variable of the same name. */
7957 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7959 add_setshow_boolean_cmd ("observer", no_class
,
7960 &observer_mode_1
, _("\
7961 Set whether gdb controls the inferior in observer mode."), _("\
7962 Show whether gdb controls the inferior in observer mode."), _("\
7963 In observer mode, GDB can get data from the inferior, but not\n\
7964 affect its execution. Registers and memory may not be changed,\n\
7965 breakpoints may not be set, and the program cannot be interrupted\n\