1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2015 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 /* Prototypes for local functions */
66 static void signals_info (char *, int);
68 static void handle_command (char *, int);
70 static void sig_print_info (enum gdb_signal
);
72 static void sig_print_header (void);
74 static void resume_cleanups (void *);
76 static int hook_stop_stub (void *);
78 static int restore_selected_frame (void *);
80 static int follow_fork (void);
82 static int follow_fork_inferior (int follow_child
, int detach_fork
);
84 static void follow_inferior_reset_breakpoints (void);
86 static void set_schedlock_func (char *args
, int from_tty
,
87 struct cmd_list_element
*c
);
89 static int currently_stepping (struct thread_info
*tp
);
91 static void xdb_handle_command (char *args
, int from_tty
);
93 void _initialize_infrun (void);
95 void nullify_last_target_wait_ptid (void);
97 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
99 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
101 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
103 /* When set, stop the 'step' command if we enter a function which has
104 no line number information. The normal behavior is that we step
105 over such function. */
106 int step_stop_if_no_debug
= 0;
108 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
109 struct cmd_list_element
*c
, const char *value
)
111 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
114 /* In asynchronous mode, but simulating synchronous execution. */
116 int sync_execution
= 0;
118 /* proceed and normal_stop use this to notify the user when the
119 inferior stopped in a different thread than it had been running
122 static ptid_t previous_inferior_ptid
;
124 /* If set (default for legacy reasons), when following a fork, GDB
125 will detach from one of the fork branches, child or parent.
126 Exactly which branch is detached depends on 'set follow-fork-mode'
129 static int detach_fork
= 1;
131 int debug_displaced
= 0;
133 show_debug_displaced (struct ui_file
*file
, int from_tty
,
134 struct cmd_list_element
*c
, const char *value
)
136 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
139 unsigned int debug_infrun
= 0;
141 show_debug_infrun (struct ui_file
*file
, int from_tty
,
142 struct cmd_list_element
*c
, const char *value
)
144 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
148 /* Support for disabling address space randomization. */
150 int disable_randomization
= 1;
153 show_disable_randomization (struct ui_file
*file
, int from_tty
,
154 struct cmd_list_element
*c
, const char *value
)
156 if (target_supports_disable_randomization ())
157 fprintf_filtered (file
,
158 _("Disabling randomization of debuggee's "
159 "virtual address space is %s.\n"),
162 fputs_filtered (_("Disabling randomization of debuggee's "
163 "virtual address space is unsupported on\n"
164 "this platform.\n"), file
);
168 set_disable_randomization (char *args
, int from_tty
,
169 struct cmd_list_element
*c
)
171 if (!target_supports_disable_randomization ())
172 error (_("Disabling randomization of debuggee's "
173 "virtual address space is unsupported on\n"
177 /* User interface for non-stop mode. */
180 static int non_stop_1
= 0;
183 set_non_stop (char *args
, int from_tty
,
184 struct cmd_list_element
*c
)
186 if (target_has_execution
)
188 non_stop_1
= non_stop
;
189 error (_("Cannot change this setting while the inferior is running."));
192 non_stop
= non_stop_1
;
196 show_non_stop (struct ui_file
*file
, int from_tty
,
197 struct cmd_list_element
*c
, const char *value
)
199 fprintf_filtered (file
,
200 _("Controlling the inferior in non-stop mode is %s.\n"),
204 /* "Observer mode" is somewhat like a more extreme version of
205 non-stop, in which all GDB operations that might affect the
206 target's execution have been disabled. */
208 int observer_mode
= 0;
209 static int observer_mode_1
= 0;
212 set_observer_mode (char *args
, int from_tty
,
213 struct cmd_list_element
*c
)
215 if (target_has_execution
)
217 observer_mode_1
= observer_mode
;
218 error (_("Cannot change this setting while the inferior is running."));
221 observer_mode
= observer_mode_1
;
223 may_write_registers
= !observer_mode
;
224 may_write_memory
= !observer_mode
;
225 may_insert_breakpoints
= !observer_mode
;
226 may_insert_tracepoints
= !observer_mode
;
227 /* We can insert fast tracepoints in or out of observer mode,
228 but enable them if we're going into this mode. */
230 may_insert_fast_tracepoints
= 1;
231 may_stop
= !observer_mode
;
232 update_target_permissions ();
234 /* Going *into* observer mode we must force non-stop, then
235 going out we leave it that way. */
238 pagination_enabled
= 0;
239 non_stop
= non_stop_1
= 1;
243 printf_filtered (_("Observer mode is now %s.\n"),
244 (observer_mode
? "on" : "off"));
248 show_observer_mode (struct ui_file
*file
, int from_tty
,
249 struct cmd_list_element
*c
, const char *value
)
251 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
254 /* This updates the value of observer mode based on changes in
255 permissions. Note that we are deliberately ignoring the values of
256 may-write-registers and may-write-memory, since the user may have
257 reason to enable these during a session, for instance to turn on a
258 debugging-related global. */
261 update_observer_mode (void)
265 newval
= (!may_insert_breakpoints
266 && !may_insert_tracepoints
267 && may_insert_fast_tracepoints
271 /* Let the user know if things change. */
272 if (newval
!= observer_mode
)
273 printf_filtered (_("Observer mode is now %s.\n"),
274 (newval
? "on" : "off"));
276 observer_mode
= observer_mode_1
= newval
;
279 /* Tables of how to react to signals; the user sets them. */
281 static unsigned char *signal_stop
;
282 static unsigned char *signal_print
;
283 static unsigned char *signal_program
;
285 /* Table of signals that are registered with "catch signal". A
286 non-zero entry indicates that the signal is caught by some "catch
287 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
289 static unsigned char *signal_catch
;
291 /* Table of signals that the target may silently handle.
292 This is automatically determined from the flags above,
293 and simply cached here. */
294 static unsigned char *signal_pass
;
296 #define SET_SIGS(nsigs,sigs,flags) \
298 int signum = (nsigs); \
299 while (signum-- > 0) \
300 if ((sigs)[signum]) \
301 (flags)[signum] = 1; \
304 #define UNSET_SIGS(nsigs,sigs,flags) \
306 int signum = (nsigs); \
307 while (signum-- > 0) \
308 if ((sigs)[signum]) \
309 (flags)[signum] = 0; \
312 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
313 this function is to avoid exporting `signal_program'. */
316 update_signals_program_target (void)
318 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
321 /* Value to pass to target_resume() to cause all threads to resume. */
323 #define RESUME_ALL minus_one_ptid
325 /* Command list pointer for the "stop" placeholder. */
327 static struct cmd_list_element
*stop_command
;
329 /* Function inferior was in as of last step command. */
331 static struct symbol
*step_start_function
;
333 /* Nonzero if we want to give control to the user when we're notified
334 of shared library events by the dynamic linker. */
335 int stop_on_solib_events
;
337 /* Enable or disable optional shared library event breakpoints
338 as appropriate when the above flag is changed. */
341 set_stop_on_solib_events (char *args
, int from_tty
, struct cmd_list_element
*c
)
343 update_solib_breakpoints ();
347 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
348 struct cmd_list_element
*c
, const char *value
)
350 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
354 /* Nonzero means expecting a trace trap
355 and should stop the inferior and return silently when it happens. */
359 /* Save register contents here when executing a "finish" command or are
360 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
361 Thus this contains the return value from the called function (assuming
362 values are returned in a register). */
364 struct regcache
*stop_registers
;
366 /* Nonzero after stop if current stack frame should be printed. */
368 static int stop_print_frame
;
370 /* This is a cached copy of the pid/waitstatus of the last event
371 returned by target_wait()/deprecated_target_wait_hook(). This
372 information is returned by get_last_target_status(). */
373 static ptid_t target_last_wait_ptid
;
374 static struct target_waitstatus target_last_waitstatus
;
376 static void context_switch (ptid_t ptid
);
378 void init_thread_stepping_state (struct thread_info
*tss
);
380 static const char follow_fork_mode_child
[] = "child";
381 static const char follow_fork_mode_parent
[] = "parent";
383 static const char *const follow_fork_mode_kind_names
[] = {
384 follow_fork_mode_child
,
385 follow_fork_mode_parent
,
389 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
391 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
392 struct cmd_list_element
*c
, const char *value
)
394 fprintf_filtered (file
,
395 _("Debugger response to a program "
396 "call of fork or vfork is \"%s\".\n"),
401 /* Handle changes to the inferior list based on the type of fork,
402 which process is being followed, and whether the other process
403 should be detached. On entry inferior_ptid must be the ptid of
404 the fork parent. At return inferior_ptid is the ptid of the
405 followed inferior. */
408 follow_fork_inferior (int follow_child
, int detach_fork
)
411 ptid_t parent_ptid
, child_ptid
;
413 has_vforked
= (inferior_thread ()->pending_follow
.kind
414 == TARGET_WAITKIND_VFORKED
);
415 parent_ptid
= inferior_ptid
;
416 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
419 && !non_stop
/* Non-stop always resumes both branches. */
420 && (!target_is_async_p () || sync_execution
)
421 && !(follow_child
|| detach_fork
|| sched_multi
))
423 /* The parent stays blocked inside the vfork syscall until the
424 child execs or exits. If we don't let the child run, then
425 the parent stays blocked. If we're telling the parent to run
426 in the foreground, the user will not be able to ctrl-c to get
427 back the terminal, effectively hanging the debug session. */
428 fprintf_filtered (gdb_stderr
, _("\
429 Can not resume the parent process over vfork in the foreground while\n\
430 holding the child stopped. Try \"set detach-on-fork\" or \
431 \"set schedule-multiple\".\n"));
432 /* FIXME output string > 80 columns. */
438 /* Detach new forked process? */
441 struct cleanup
*old_chain
;
443 /* Before detaching from the child, remove all breakpoints
444 from it. If we forked, then this has already been taken
445 care of by infrun.c. If we vforked however, any
446 breakpoint inserted in the parent is visible in the
447 child, even those added while stopped in a vfork
448 catchpoint. This will remove the breakpoints from the
449 parent also, but they'll be reinserted below. */
452 /* Keep breakpoints list in sync. */
453 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
456 if (info_verbose
|| debug_infrun
)
458 target_terminal_ours_for_output ();
459 fprintf_filtered (gdb_stdlog
,
460 _("Detaching after %s from child %s.\n"),
461 has_vforked
? "vfork" : "fork",
462 target_pid_to_str (child_ptid
));
467 struct inferior
*parent_inf
, *child_inf
;
468 struct cleanup
*old_chain
;
470 /* Add process to GDB's tables. */
471 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
473 parent_inf
= current_inferior ();
474 child_inf
->attach_flag
= parent_inf
->attach_flag
;
475 copy_terminal_info (child_inf
, parent_inf
);
476 child_inf
->gdbarch
= parent_inf
->gdbarch
;
477 copy_inferior_target_desc_info (child_inf
, parent_inf
);
479 old_chain
= save_inferior_ptid ();
480 save_current_program_space ();
482 inferior_ptid
= child_ptid
;
483 add_thread (inferior_ptid
);
484 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
486 /* If this is a vfork child, then the address-space is
487 shared with the parent. */
490 child_inf
->pspace
= parent_inf
->pspace
;
491 child_inf
->aspace
= parent_inf
->aspace
;
493 /* The parent will be frozen until the child is done
494 with the shared region. Keep track of the
496 child_inf
->vfork_parent
= parent_inf
;
497 child_inf
->pending_detach
= 0;
498 parent_inf
->vfork_child
= child_inf
;
499 parent_inf
->pending_detach
= 0;
503 child_inf
->aspace
= new_address_space ();
504 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
505 child_inf
->removable
= 1;
506 set_current_program_space (child_inf
->pspace
);
507 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
509 /* Let the shared library layer (e.g., solib-svr4) learn
510 about this new process, relocate the cloned exec, pull
511 in shared libraries, and install the solib event
512 breakpoint. If a "cloned-VM" event was propagated
513 better throughout the core, this wouldn't be
515 solib_create_inferior_hook (0);
518 do_cleanups (old_chain
);
523 struct inferior
*parent_inf
;
525 parent_inf
= current_inferior ();
527 /* If we detached from the child, then we have to be careful
528 to not insert breakpoints in the parent until the child
529 is done with the shared memory region. However, if we're
530 staying attached to the child, then we can and should
531 insert breakpoints, so that we can debug it. A
532 subsequent child exec or exit is enough to know when does
533 the child stops using the parent's address space. */
534 parent_inf
->waiting_for_vfork_done
= detach_fork
;
535 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
540 /* Follow the child. */
541 struct inferior
*parent_inf
, *child_inf
;
542 struct program_space
*parent_pspace
;
544 if (info_verbose
|| debug_infrun
)
546 target_terminal_ours_for_output ();
547 fprintf_filtered (gdb_stdlog
,
548 _("Attaching after %s %s to child %s.\n"),
549 target_pid_to_str (parent_ptid
),
550 has_vforked
? "vfork" : "fork",
551 target_pid_to_str (child_ptid
));
554 /* Add the new inferior first, so that the target_detach below
555 doesn't unpush the target. */
557 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
559 parent_inf
= current_inferior ();
560 child_inf
->attach_flag
= parent_inf
->attach_flag
;
561 copy_terminal_info (child_inf
, parent_inf
);
562 child_inf
->gdbarch
= parent_inf
->gdbarch
;
563 copy_inferior_target_desc_info (child_inf
, parent_inf
);
565 parent_pspace
= parent_inf
->pspace
;
567 /* If we're vforking, we want to hold on to the parent until the
568 child exits or execs. At child exec or exit time we can
569 remove the old breakpoints from the parent and detach or
570 resume debugging it. Otherwise, detach the parent now; we'll
571 want to reuse it's program/address spaces, but we can't set
572 them to the child before removing breakpoints from the
573 parent, otherwise, the breakpoints module could decide to
574 remove breakpoints from the wrong process (since they'd be
575 assigned to the same address space). */
579 gdb_assert (child_inf
->vfork_parent
== NULL
);
580 gdb_assert (parent_inf
->vfork_child
== NULL
);
581 child_inf
->vfork_parent
= parent_inf
;
582 child_inf
->pending_detach
= 0;
583 parent_inf
->vfork_child
= child_inf
;
584 parent_inf
->pending_detach
= detach_fork
;
585 parent_inf
->waiting_for_vfork_done
= 0;
587 else if (detach_fork
)
589 if (info_verbose
|| debug_infrun
)
591 target_terminal_ours_for_output ();
592 fprintf_filtered (gdb_stdlog
,
593 _("Detaching after fork from "
595 target_pid_to_str (child_ptid
));
598 target_detach (NULL
, 0);
601 /* Note that the detach above makes PARENT_INF dangling. */
603 /* Add the child thread to the appropriate lists, and switch to
604 this new thread, before cloning the program space, and
605 informing the solib layer about this new process. */
607 inferior_ptid
= child_ptid
;
608 add_thread (inferior_ptid
);
610 /* If this is a vfork child, then the address-space is shared
611 with the parent. If we detached from the parent, then we can
612 reuse the parent's program/address spaces. */
613 if (has_vforked
|| detach_fork
)
615 child_inf
->pspace
= parent_pspace
;
616 child_inf
->aspace
= child_inf
->pspace
->aspace
;
620 child_inf
->aspace
= new_address_space ();
621 child_inf
->pspace
= add_program_space (child_inf
->aspace
);
622 child_inf
->removable
= 1;
623 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
624 set_current_program_space (child_inf
->pspace
);
625 clone_program_space (child_inf
->pspace
, parent_pspace
);
627 /* Let the shared library layer (e.g., solib-svr4) learn
628 about this new process, relocate the cloned exec, pull in
629 shared libraries, and install the solib event breakpoint.
630 If a "cloned-VM" event was propagated better throughout
631 the core, this wouldn't be required. */
632 solib_create_inferior_hook (0);
636 return target_follow_fork (follow_child
, detach_fork
);
639 /* Tell the target to follow the fork we're stopped at. Returns true
640 if the inferior should be resumed; false, if the target for some
641 reason decided it's best not to resume. */
646 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
647 int should_resume
= 1;
648 struct thread_info
*tp
;
650 /* Copy user stepping state to the new inferior thread. FIXME: the
651 followed fork child thread should have a copy of most of the
652 parent thread structure's run control related fields, not just these.
653 Initialized to avoid "may be used uninitialized" warnings from gcc. */
654 struct breakpoint
*step_resume_breakpoint
= NULL
;
655 struct breakpoint
*exception_resume_breakpoint
= NULL
;
656 CORE_ADDR step_range_start
= 0;
657 CORE_ADDR step_range_end
= 0;
658 struct frame_id step_frame_id
= { 0 };
659 struct interp
*command_interp
= NULL
;
664 struct target_waitstatus wait_status
;
666 /* Get the last target status returned by target_wait(). */
667 get_last_target_status (&wait_ptid
, &wait_status
);
669 /* If not stopped at a fork event, then there's nothing else to
671 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
672 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
675 /* Check if we switched over from WAIT_PTID, since the event was
677 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
678 && !ptid_equal (inferior_ptid
, wait_ptid
))
680 /* We did. Switch back to WAIT_PTID thread, to tell the
681 target to follow it (in either direction). We'll
682 afterwards refuse to resume, and inform the user what
684 switch_to_thread (wait_ptid
);
689 tp
= inferior_thread ();
691 /* If there were any forks/vforks that were caught and are now to be
692 followed, then do so now. */
693 switch (tp
->pending_follow
.kind
)
695 case TARGET_WAITKIND_FORKED
:
696 case TARGET_WAITKIND_VFORKED
:
698 ptid_t parent
, child
;
700 /* If the user did a next/step, etc, over a fork call,
701 preserve the stepping state in the fork child. */
702 if (follow_child
&& should_resume
)
704 step_resume_breakpoint
= clone_momentary_breakpoint
705 (tp
->control
.step_resume_breakpoint
);
706 step_range_start
= tp
->control
.step_range_start
;
707 step_range_end
= tp
->control
.step_range_end
;
708 step_frame_id
= tp
->control
.step_frame_id
;
709 exception_resume_breakpoint
710 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
711 command_interp
= tp
->control
.command_interp
;
713 /* For now, delete the parent's sr breakpoint, otherwise,
714 parent/child sr breakpoints are considered duplicates,
715 and the child version will not be installed. Remove
716 this when the breakpoints module becomes aware of
717 inferiors and address spaces. */
718 delete_step_resume_breakpoint (tp
);
719 tp
->control
.step_range_start
= 0;
720 tp
->control
.step_range_end
= 0;
721 tp
->control
.step_frame_id
= null_frame_id
;
722 delete_exception_resume_breakpoint (tp
);
723 tp
->control
.command_interp
= NULL
;
726 parent
= inferior_ptid
;
727 child
= tp
->pending_follow
.value
.related_pid
;
729 /* Set up inferior(s) as specified by the caller, and tell the
730 target to do whatever is necessary to follow either parent
732 if (follow_fork_inferior (follow_child
, detach_fork
))
734 /* Target refused to follow, or there's some other reason
735 we shouldn't resume. */
740 /* This pending follow fork event is now handled, one way
741 or another. The previous selected thread may be gone
742 from the lists by now, but if it is still around, need
743 to clear the pending follow request. */
744 tp
= find_thread_ptid (parent
);
746 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
748 /* This makes sure we don't try to apply the "Switched
749 over from WAIT_PID" logic above. */
750 nullify_last_target_wait_ptid ();
752 /* If we followed the child, switch to it... */
755 switch_to_thread (child
);
757 /* ... and preserve the stepping state, in case the
758 user was stepping over the fork call. */
761 tp
= inferior_thread ();
762 tp
->control
.step_resume_breakpoint
763 = step_resume_breakpoint
;
764 tp
->control
.step_range_start
= step_range_start
;
765 tp
->control
.step_range_end
= step_range_end
;
766 tp
->control
.step_frame_id
= step_frame_id
;
767 tp
->control
.exception_resume_breakpoint
768 = exception_resume_breakpoint
;
769 tp
->control
.command_interp
= command_interp
;
773 /* If we get here, it was because we're trying to
774 resume from a fork catchpoint, but, the user
775 has switched threads away from the thread that
776 forked. In that case, the resume command
777 issued is most likely not applicable to the
778 child, so just warn, and refuse to resume. */
779 warning (_("Not resuming: switched threads "
780 "before following fork child.\n"));
783 /* Reset breakpoints in the child as appropriate. */
784 follow_inferior_reset_breakpoints ();
787 switch_to_thread (parent
);
791 case TARGET_WAITKIND_SPURIOUS
:
792 /* Nothing to follow. */
795 internal_error (__FILE__
, __LINE__
,
796 "Unexpected pending_follow.kind %d\n",
797 tp
->pending_follow
.kind
);
801 return should_resume
;
805 follow_inferior_reset_breakpoints (void)
807 struct thread_info
*tp
= inferior_thread ();
809 /* Was there a step_resume breakpoint? (There was if the user
810 did a "next" at the fork() call.) If so, explicitly reset its
811 thread number. Cloned step_resume breakpoints are disabled on
812 creation, so enable it here now that it is associated with the
815 step_resumes are a form of bp that are made to be per-thread.
816 Since we created the step_resume bp when the parent process
817 was being debugged, and now are switching to the child process,
818 from the breakpoint package's viewpoint, that's a switch of
819 "threads". We must update the bp's notion of which thread
820 it is for, or it'll be ignored when it triggers. */
822 if (tp
->control
.step_resume_breakpoint
)
824 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
825 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
828 /* Treat exception_resume breakpoints like step_resume breakpoints. */
829 if (tp
->control
.exception_resume_breakpoint
)
831 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
832 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
835 /* Reinsert all breakpoints in the child. The user may have set
836 breakpoints after catching the fork, in which case those
837 were never set in the child, but only in the parent. This makes
838 sure the inserted breakpoints match the breakpoint list. */
840 breakpoint_re_set ();
841 insert_breakpoints ();
844 /* The child has exited or execed: resume threads of the parent the
845 user wanted to be executing. */
848 proceed_after_vfork_done (struct thread_info
*thread
,
851 int pid
= * (int *) arg
;
853 if (ptid_get_pid (thread
->ptid
) == pid
854 && is_running (thread
->ptid
)
855 && !is_executing (thread
->ptid
)
856 && !thread
->stop_requested
857 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
860 fprintf_unfiltered (gdb_stdlog
,
861 "infrun: resuming vfork parent thread %s\n",
862 target_pid_to_str (thread
->ptid
));
864 switch_to_thread (thread
->ptid
);
865 clear_proceed_status (0);
866 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
, 0);
872 /* Called whenever we notice an exec or exit event, to handle
873 detaching or resuming a vfork parent. */
876 handle_vfork_child_exec_or_exit (int exec
)
878 struct inferior
*inf
= current_inferior ();
880 if (inf
->vfork_parent
)
882 int resume_parent
= -1;
884 /* This exec or exit marks the end of the shared memory region
885 between the parent and the child. If the user wanted to
886 detach from the parent, now is the time. */
888 if (inf
->vfork_parent
->pending_detach
)
890 struct thread_info
*tp
;
891 struct cleanup
*old_chain
;
892 struct program_space
*pspace
;
893 struct address_space
*aspace
;
895 /* follow-fork child, detach-on-fork on. */
897 inf
->vfork_parent
->pending_detach
= 0;
901 /* If we're handling a child exit, then inferior_ptid
902 points at the inferior's pid, not to a thread. */
903 old_chain
= save_inferior_ptid ();
904 save_current_program_space ();
905 save_current_inferior ();
908 old_chain
= save_current_space_and_thread ();
910 /* We're letting loose of the parent. */
911 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
912 switch_to_thread (tp
->ptid
);
914 /* We're about to detach from the parent, which implicitly
915 removes breakpoints from its address space. There's a
916 catch here: we want to reuse the spaces for the child,
917 but, parent/child are still sharing the pspace at this
918 point, although the exec in reality makes the kernel give
919 the child a fresh set of new pages. The problem here is
920 that the breakpoints module being unaware of this, would
921 likely chose the child process to write to the parent
922 address space. Swapping the child temporarily away from
923 the spaces has the desired effect. Yes, this is "sort
926 pspace
= inf
->pspace
;
927 aspace
= inf
->aspace
;
931 if (debug_infrun
|| info_verbose
)
933 target_terminal_ours_for_output ();
937 fprintf_filtered (gdb_stdlog
,
938 _("Detaching vfork parent process "
939 "%d after child exec.\n"),
940 inf
->vfork_parent
->pid
);
944 fprintf_filtered (gdb_stdlog
,
945 _("Detaching vfork parent process "
946 "%d after child exit.\n"),
947 inf
->vfork_parent
->pid
);
951 target_detach (NULL
, 0);
954 inf
->pspace
= pspace
;
955 inf
->aspace
= aspace
;
957 do_cleanups (old_chain
);
961 /* We're staying attached to the parent, so, really give the
962 child a new address space. */
963 inf
->pspace
= add_program_space (maybe_new_address_space ());
964 inf
->aspace
= inf
->pspace
->aspace
;
966 set_current_program_space (inf
->pspace
);
968 resume_parent
= inf
->vfork_parent
->pid
;
970 /* Break the bonds. */
971 inf
->vfork_parent
->vfork_child
= NULL
;
975 struct cleanup
*old_chain
;
976 struct program_space
*pspace
;
978 /* If this is a vfork child exiting, then the pspace and
979 aspaces were shared with the parent. Since we're
980 reporting the process exit, we'll be mourning all that is
981 found in the address space, and switching to null_ptid,
982 preparing to start a new inferior. But, since we don't
983 want to clobber the parent's address/program spaces, we
984 go ahead and create a new one for this exiting
987 /* Switch to null_ptid, so that clone_program_space doesn't want
988 to read the selected frame of a dead process. */
989 old_chain
= save_inferior_ptid ();
990 inferior_ptid
= null_ptid
;
992 /* This inferior is dead, so avoid giving the breakpoints
993 module the option to write through to it (cloning a
994 program space resets breakpoints). */
997 pspace
= add_program_space (maybe_new_address_space ());
998 set_current_program_space (pspace
);
1000 inf
->symfile_flags
= SYMFILE_NO_READ
;
1001 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1002 inf
->pspace
= pspace
;
1003 inf
->aspace
= pspace
->aspace
;
1005 /* Put back inferior_ptid. We'll continue mourning this
1007 do_cleanups (old_chain
);
1009 resume_parent
= inf
->vfork_parent
->pid
;
1010 /* Break the bonds. */
1011 inf
->vfork_parent
->vfork_child
= NULL
;
1014 inf
->vfork_parent
= NULL
;
1016 gdb_assert (current_program_space
== inf
->pspace
);
1018 if (non_stop
&& resume_parent
!= -1)
1020 /* If the user wanted the parent to be running, let it go
1022 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
1025 fprintf_unfiltered (gdb_stdlog
,
1026 "infrun: resuming vfork parent process %d\n",
1029 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1031 do_cleanups (old_chain
);
1036 /* Enum strings for "set|show follow-exec-mode". */
1038 static const char follow_exec_mode_new
[] = "new";
1039 static const char follow_exec_mode_same
[] = "same";
1040 static const char *const follow_exec_mode_names
[] =
1042 follow_exec_mode_new
,
1043 follow_exec_mode_same
,
1047 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1049 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1050 struct cmd_list_element
*c
, const char *value
)
1052 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1055 /* EXECD_PATHNAME is assumed to be non-NULL. */
1058 follow_exec (ptid_t ptid
, char *execd_pathname
)
1060 struct thread_info
*th
, *tmp
;
1061 struct inferior
*inf
= current_inferior ();
1062 int pid
= ptid_get_pid (ptid
);
1064 /* This is an exec event that we actually wish to pay attention to.
1065 Refresh our symbol table to the newly exec'd program, remove any
1066 momentary bp's, etc.
1068 If there are breakpoints, they aren't really inserted now,
1069 since the exec() transformed our inferior into a fresh set
1072 We want to preserve symbolic breakpoints on the list, since
1073 we have hopes that they can be reset after the new a.out's
1074 symbol table is read.
1076 However, any "raw" breakpoints must be removed from the list
1077 (e.g., the solib bp's), since their address is probably invalid
1080 And, we DON'T want to call delete_breakpoints() here, since
1081 that may write the bp's "shadow contents" (the instruction
1082 value that was overwritten witha TRAP instruction). Since
1083 we now have a new a.out, those shadow contents aren't valid. */
1085 mark_breakpoints_out ();
1087 /* The target reports the exec event to the main thread, even if
1088 some other thread does the exec, and even if the main thread was
1089 stopped or already gone. We may still have non-leader threads of
1090 the process on our list. E.g., on targets that don't have thread
1091 exit events (like remote); or on native Linux in non-stop mode if
1092 there were only two threads in the inferior and the non-leader
1093 one is the one that execs (and nothing forces an update of the
1094 thread list up to here). When debugging remotely, it's best to
1095 avoid extra traffic, when possible, so avoid syncing the thread
1096 list with the target, and instead go ahead and delete all threads
1097 of the process but one that reported the event. Note this must
1098 be done before calling update_breakpoints_after_exec, as
1099 otherwise clearing the threads' resources would reference stale
1100 thread breakpoints -- it may have been one of these threads that
1101 stepped across the exec. We could just clear their stepping
1102 states, but as long as we're iterating, might as well delete
1103 them. Deleting them now rather than at the next user-visible
1104 stop provides a nicer sequence of events for user and MI
1106 ALL_NON_EXITED_THREADS_SAFE (th
, tmp
)
1107 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1108 delete_thread (th
->ptid
);
1110 /* We also need to clear any left over stale state for the
1111 leader/event thread. E.g., if there was any step-resume
1112 breakpoint or similar, it's gone now. We cannot truly
1113 step-to-next statement through an exec(). */
1114 th
= inferior_thread ();
1115 th
->control
.step_resume_breakpoint
= NULL
;
1116 th
->control
.exception_resume_breakpoint
= NULL
;
1117 th
->control
.single_step_breakpoints
= NULL
;
1118 th
->control
.step_range_start
= 0;
1119 th
->control
.step_range_end
= 0;
1121 /* The user may have had the main thread held stopped in the
1122 previous image (e.g., schedlock on, or non-stop). Release
1124 th
->stop_requested
= 0;
1126 update_breakpoints_after_exec ();
1128 /* What is this a.out's name? */
1129 printf_unfiltered (_("%s is executing new program: %s\n"),
1130 target_pid_to_str (inferior_ptid
),
1133 /* We've followed the inferior through an exec. Therefore, the
1134 inferior has essentially been killed & reborn. */
1136 gdb_flush (gdb_stdout
);
1138 breakpoint_init_inferior (inf_execd
);
1140 if (gdb_sysroot
&& *gdb_sysroot
)
1142 char *name
= alloca (strlen (gdb_sysroot
)
1143 + strlen (execd_pathname
)
1146 strcpy (name
, gdb_sysroot
);
1147 strcat (name
, execd_pathname
);
1148 execd_pathname
= name
;
1151 /* Reset the shared library package. This ensures that we get a
1152 shlib event when the child reaches "_start", at which point the
1153 dld will have had a chance to initialize the child. */
1154 /* Also, loading a symbol file below may trigger symbol lookups, and
1155 we don't want those to be satisfied by the libraries of the
1156 previous incarnation of this process. */
1157 no_shared_libraries (NULL
, 0);
1159 if (follow_exec_mode_string
== follow_exec_mode_new
)
1161 struct program_space
*pspace
;
1163 /* The user wants to keep the old inferior and program spaces
1164 around. Create a new fresh one, and switch to it. */
1166 inf
= add_inferior (current_inferior ()->pid
);
1167 pspace
= add_program_space (maybe_new_address_space ());
1168 inf
->pspace
= pspace
;
1169 inf
->aspace
= pspace
->aspace
;
1171 exit_inferior_num_silent (current_inferior ()->num
);
1173 set_current_inferior (inf
);
1174 set_current_program_space (pspace
);
1178 /* The old description may no longer be fit for the new image.
1179 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1180 old description; we'll read a new one below. No need to do
1181 this on "follow-exec-mode new", as the old inferior stays
1182 around (its description is later cleared/refetched on
1184 target_clear_description ();
1187 gdb_assert (current_program_space
== inf
->pspace
);
1189 /* That a.out is now the one to use. */
1190 exec_file_attach (execd_pathname
, 0);
1192 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
1193 (Position Independent Executable) main symbol file will get applied by
1194 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
1195 the breakpoints with the zero displacement. */
1197 symbol_file_add (execd_pathname
,
1199 | SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
),
1202 if ((inf
->symfile_flags
& SYMFILE_NO_READ
) == 0)
1203 set_initial_language ();
1205 /* If the target can specify a description, read it. Must do this
1206 after flipping to the new executable (because the target supplied
1207 description must be compatible with the executable's
1208 architecture, and the old executable may e.g., be 32-bit, while
1209 the new one 64-bit), and before anything involving memory or
1211 target_find_description ();
1213 solib_create_inferior_hook (0);
1215 jit_inferior_created_hook ();
1217 breakpoint_re_set ();
1219 /* Reinsert all breakpoints. (Those which were symbolic have
1220 been reset to the proper address in the new a.out, thanks
1221 to symbol_file_command...). */
1222 insert_breakpoints ();
1224 /* The next resume of this inferior should bring it to the shlib
1225 startup breakpoints. (If the user had also set bp's on
1226 "main" from the old (parent) process, then they'll auto-
1227 matically get reset there in the new process.). */
1230 /* Info about an instruction that is being stepped over. */
1232 struct step_over_info
1234 /* If we're stepping past a breakpoint, this is the address space
1235 and address of the instruction the breakpoint is set at. We'll
1236 skip inserting all breakpoints here. Valid iff ASPACE is
1238 struct address_space
*aspace
;
1241 /* The instruction being stepped over triggers a nonsteppable
1242 watchpoint. If true, we'll skip inserting watchpoints. */
1243 int nonsteppable_watchpoint_p
;
1246 /* The step-over info of the location that is being stepped over.
1248 Note that with async/breakpoint always-inserted mode, a user might
1249 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1250 being stepped over. As setting a new breakpoint inserts all
1251 breakpoints, we need to make sure the breakpoint being stepped over
1252 isn't inserted then. We do that by only clearing the step-over
1253 info when the step-over is actually finished (or aborted).
1255 Presently GDB can only step over one breakpoint at any given time.
1256 Given threads that can't run code in the same address space as the
1257 breakpoint's can't really miss the breakpoint, GDB could be taught
1258 to step-over at most one breakpoint per address space (so this info
1259 could move to the address space object if/when GDB is extended).
1260 The set of breakpoints being stepped over will normally be much
1261 smaller than the set of all breakpoints, so a flag in the
1262 breakpoint location structure would be wasteful. A separate list
1263 also saves complexity and run-time, as otherwise we'd have to go
1264 through all breakpoint locations clearing their flag whenever we
1265 start a new sequence. Similar considerations weigh against storing
1266 this info in the thread object. Plus, not all step overs actually
1267 have breakpoint locations -- e.g., stepping past a single-step
1268 breakpoint, or stepping to complete a non-continuable
1270 static struct step_over_info step_over_info
;
1272 /* Record the address of the breakpoint/instruction we're currently
1276 set_step_over_info (struct address_space
*aspace
, CORE_ADDR address
,
1277 int nonsteppable_watchpoint_p
)
1279 step_over_info
.aspace
= aspace
;
1280 step_over_info
.address
= address
;
1281 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1284 /* Called when we're not longer stepping over a breakpoint / an
1285 instruction, so all breakpoints are free to be (re)inserted. */
1288 clear_step_over_info (void)
1290 step_over_info
.aspace
= NULL
;
1291 step_over_info
.address
= 0;
1292 step_over_info
.nonsteppable_watchpoint_p
= 0;
1298 stepping_past_instruction_at (struct address_space
*aspace
,
1301 return (step_over_info
.aspace
!= NULL
1302 && breakpoint_address_match (aspace
, address
,
1303 step_over_info
.aspace
,
1304 step_over_info
.address
));
1310 stepping_past_nonsteppable_watchpoint (void)
1312 return step_over_info
.nonsteppable_watchpoint_p
;
1315 /* Returns true if step-over info is valid. */
1318 step_over_info_valid_p (void)
1320 return (step_over_info
.aspace
!= NULL
1321 || stepping_past_nonsteppable_watchpoint ());
1325 /* Displaced stepping. */
1327 /* In non-stop debugging mode, we must take special care to manage
1328 breakpoints properly; in particular, the traditional strategy for
1329 stepping a thread past a breakpoint it has hit is unsuitable.
1330 'Displaced stepping' is a tactic for stepping one thread past a
1331 breakpoint it has hit while ensuring that other threads running
1332 concurrently will hit the breakpoint as they should.
1334 The traditional way to step a thread T off a breakpoint in a
1335 multi-threaded program in all-stop mode is as follows:
1337 a0) Initially, all threads are stopped, and breakpoints are not
1339 a1) We single-step T, leaving breakpoints uninserted.
1340 a2) We insert breakpoints, and resume all threads.
1342 In non-stop debugging, however, this strategy is unsuitable: we
1343 don't want to have to stop all threads in the system in order to
1344 continue or step T past a breakpoint. Instead, we use displaced
1347 n0) Initially, T is stopped, other threads are running, and
1348 breakpoints are inserted.
1349 n1) We copy the instruction "under" the breakpoint to a separate
1350 location, outside the main code stream, making any adjustments
1351 to the instruction, register, and memory state as directed by
1353 n2) We single-step T over the instruction at its new location.
1354 n3) We adjust the resulting register and memory state as directed
1355 by T's architecture. This includes resetting T's PC to point
1356 back into the main instruction stream.
1359 This approach depends on the following gdbarch methods:
1361 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1362 indicate where to copy the instruction, and how much space must
1363 be reserved there. We use these in step n1.
1365 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1366 address, and makes any necessary adjustments to the instruction,
1367 register contents, and memory. We use this in step n1.
1369 - gdbarch_displaced_step_fixup adjusts registers and memory after
1370 we have successfuly single-stepped the instruction, to yield the
1371 same effect the instruction would have had if we had executed it
1372 at its original address. We use this in step n3.
1374 - gdbarch_displaced_step_free_closure provides cleanup.
1376 The gdbarch_displaced_step_copy_insn and
1377 gdbarch_displaced_step_fixup functions must be written so that
1378 copying an instruction with gdbarch_displaced_step_copy_insn,
1379 single-stepping across the copied instruction, and then applying
1380 gdbarch_displaced_insn_fixup should have the same effects on the
1381 thread's memory and registers as stepping the instruction in place
1382 would have. Exactly which responsibilities fall to the copy and
1383 which fall to the fixup is up to the author of those functions.
1385 See the comments in gdbarch.sh for details.
1387 Note that displaced stepping and software single-step cannot
1388 currently be used in combination, although with some care I think
1389 they could be made to. Software single-step works by placing
1390 breakpoints on all possible subsequent instructions; if the
1391 displaced instruction is a PC-relative jump, those breakpoints
1392 could fall in very strange places --- on pages that aren't
1393 executable, or at addresses that are not proper instruction
1394 boundaries. (We do generally let other threads run while we wait
1395 to hit the software single-step breakpoint, and they might
1396 encounter such a corrupted instruction.) One way to work around
1397 this would be to have gdbarch_displaced_step_copy_insn fully
1398 simulate the effect of PC-relative instructions (and return NULL)
1399 on architectures that use software single-stepping.
1401 In non-stop mode, we can have independent and simultaneous step
1402 requests, so more than one thread may need to simultaneously step
1403 over a breakpoint. The current implementation assumes there is
1404 only one scratch space per process. In this case, we have to
1405 serialize access to the scratch space. If thread A wants to step
1406 over a breakpoint, but we are currently waiting for some other
1407 thread to complete a displaced step, we leave thread A stopped and
1408 place it in the displaced_step_request_queue. Whenever a displaced
1409 step finishes, we pick the next thread in the queue and start a new
1410 displaced step operation on it. See displaced_step_prepare and
1411 displaced_step_fixup for details. */
1413 struct displaced_step_request
1416 struct displaced_step_request
*next
;
1419 /* Per-inferior displaced stepping state. */
1420 struct displaced_step_inferior_state
1422 /* Pointer to next in linked list. */
1423 struct displaced_step_inferior_state
*next
;
1425 /* The process this displaced step state refers to. */
1428 /* A queue of pending displaced stepping requests. One entry per
1429 thread that needs to do a displaced step. */
1430 struct displaced_step_request
*step_request_queue
;
1432 /* If this is not null_ptid, this is the thread carrying out a
1433 displaced single-step in process PID. This thread's state will
1434 require fixing up once it has completed its step. */
1437 /* The architecture the thread had when we stepped it. */
1438 struct gdbarch
*step_gdbarch
;
1440 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1441 for post-step cleanup. */
1442 struct displaced_step_closure
*step_closure
;
1444 /* The address of the original instruction, and the copy we
1446 CORE_ADDR step_original
, step_copy
;
1448 /* Saved contents of copy area. */
1449 gdb_byte
*step_saved_copy
;
1452 /* The list of states of processes involved in displaced stepping
1454 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1456 /* Get the displaced stepping state of process PID. */
1458 static struct displaced_step_inferior_state
*
1459 get_displaced_stepping_state (int pid
)
1461 struct displaced_step_inferior_state
*state
;
1463 for (state
= displaced_step_inferior_states
;
1465 state
= state
->next
)
1466 if (state
->pid
== pid
)
1472 /* Add a new displaced stepping state for process PID to the displaced
1473 stepping state list, or return a pointer to an already existing
1474 entry, if it already exists. Never returns NULL. */
1476 static struct displaced_step_inferior_state
*
1477 add_displaced_stepping_state (int pid
)
1479 struct displaced_step_inferior_state
*state
;
1481 for (state
= displaced_step_inferior_states
;
1483 state
= state
->next
)
1484 if (state
->pid
== pid
)
1487 state
= xcalloc (1, sizeof (*state
));
1489 state
->next
= displaced_step_inferior_states
;
1490 displaced_step_inferior_states
= state
;
1495 /* If inferior is in displaced stepping, and ADDR equals to starting address
1496 of copy area, return corresponding displaced_step_closure. Otherwise,
1499 struct displaced_step_closure
*
1500 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1502 struct displaced_step_inferior_state
*displaced
1503 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1505 /* If checking the mode of displaced instruction in copy area. */
1506 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1507 && (displaced
->step_copy
== addr
))
1508 return displaced
->step_closure
;
1513 /* Remove the displaced stepping state of process PID. */
1516 remove_displaced_stepping_state (int pid
)
1518 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1520 gdb_assert (pid
!= 0);
1522 it
= displaced_step_inferior_states
;
1523 prev_next_p
= &displaced_step_inferior_states
;
1528 *prev_next_p
= it
->next
;
1533 prev_next_p
= &it
->next
;
1539 infrun_inferior_exit (struct inferior
*inf
)
1541 remove_displaced_stepping_state (inf
->pid
);
1544 /* If ON, and the architecture supports it, GDB will use displaced
1545 stepping to step over breakpoints. If OFF, or if the architecture
1546 doesn't support it, GDB will instead use the traditional
1547 hold-and-step approach. If AUTO (which is the default), GDB will
1548 decide which technique to use to step over breakpoints depending on
1549 which of all-stop or non-stop mode is active --- displaced stepping
1550 in non-stop mode; hold-and-step in all-stop mode. */
1552 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1555 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1556 struct cmd_list_element
*c
,
1559 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1560 fprintf_filtered (file
,
1561 _("Debugger's willingness to use displaced stepping "
1562 "to step over breakpoints is %s (currently %s).\n"),
1563 value
, non_stop
? "on" : "off");
1565 fprintf_filtered (file
,
1566 _("Debugger's willingness to use displaced stepping "
1567 "to step over breakpoints is %s.\n"), value
);
1570 /* Return non-zero if displaced stepping can/should be used to step
1571 over breakpoints. */
1574 use_displaced_stepping (struct gdbarch
*gdbarch
)
1576 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
&& non_stop
)
1577 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1578 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1579 && find_record_target () == NULL
);
1582 /* Clean out any stray displaced stepping state. */
1584 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1586 /* Indicate that there is no cleanup pending. */
1587 displaced
->step_ptid
= null_ptid
;
1589 if (displaced
->step_closure
)
1591 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1592 displaced
->step_closure
);
1593 displaced
->step_closure
= NULL
;
1598 displaced_step_clear_cleanup (void *arg
)
1600 struct displaced_step_inferior_state
*state
= arg
;
1602 displaced_step_clear (state
);
1605 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1607 displaced_step_dump_bytes (struct ui_file
*file
,
1608 const gdb_byte
*buf
,
1613 for (i
= 0; i
< len
; i
++)
1614 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1615 fputs_unfiltered ("\n", file
);
1618 /* Prepare to single-step, using displaced stepping.
1620 Note that we cannot use displaced stepping when we have a signal to
1621 deliver. If we have a signal to deliver and an instruction to step
1622 over, then after the step, there will be no indication from the
1623 target whether the thread entered a signal handler or ignored the
1624 signal and stepped over the instruction successfully --- both cases
1625 result in a simple SIGTRAP. In the first case we mustn't do a
1626 fixup, and in the second case we must --- but we can't tell which.
1627 Comments in the code for 'random signals' in handle_inferior_event
1628 explain how we handle this case instead.
1630 Returns 1 if preparing was successful -- this thread is going to be
1631 stepped now; or 0 if displaced stepping this thread got queued. */
1633 displaced_step_prepare (ptid_t ptid
)
1635 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1636 struct thread_info
*tp
= find_thread_ptid (ptid
);
1637 struct regcache
*regcache
= get_thread_regcache (ptid
);
1638 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1639 CORE_ADDR original
, copy
;
1641 struct displaced_step_closure
*closure
;
1642 struct displaced_step_inferior_state
*displaced
;
1645 /* We should never reach this function if the architecture does not
1646 support displaced stepping. */
1647 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1649 /* Disable range stepping while executing in the scratch pad. We
1650 want a single-step even if executing the displaced instruction in
1651 the scratch buffer lands within the stepping range (e.g., a
1653 tp
->control
.may_range_step
= 0;
1655 /* We have to displaced step one thread at a time, as we only have
1656 access to a single scratch space per inferior. */
1658 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1660 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1662 /* Already waiting for a displaced step to finish. Defer this
1663 request and place in queue. */
1664 struct displaced_step_request
*req
, *new_req
;
1666 if (debug_displaced
)
1667 fprintf_unfiltered (gdb_stdlog
,
1668 "displaced: defering step of %s\n",
1669 target_pid_to_str (ptid
));
1671 new_req
= xmalloc (sizeof (*new_req
));
1672 new_req
->ptid
= ptid
;
1673 new_req
->next
= NULL
;
1675 if (displaced
->step_request_queue
)
1677 for (req
= displaced
->step_request_queue
;
1681 req
->next
= new_req
;
1684 displaced
->step_request_queue
= new_req
;
1690 if (debug_displaced
)
1691 fprintf_unfiltered (gdb_stdlog
,
1692 "displaced: stepping %s now\n",
1693 target_pid_to_str (ptid
));
1696 displaced_step_clear (displaced
);
1698 old_cleanups
= save_inferior_ptid ();
1699 inferior_ptid
= ptid
;
1701 original
= regcache_read_pc (regcache
);
1703 copy
= gdbarch_displaced_step_location (gdbarch
);
1704 len
= gdbarch_max_insn_length (gdbarch
);
1706 /* Save the original contents of the copy area. */
1707 displaced
->step_saved_copy
= xmalloc (len
);
1708 ignore_cleanups
= make_cleanup (free_current_contents
,
1709 &displaced
->step_saved_copy
);
1710 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1712 throw_error (MEMORY_ERROR
,
1713 _("Error accessing memory address %s (%s) for "
1714 "displaced-stepping scratch space."),
1715 paddress (gdbarch
, copy
), safe_strerror (status
));
1716 if (debug_displaced
)
1718 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1719 paddress (gdbarch
, copy
));
1720 displaced_step_dump_bytes (gdb_stdlog
,
1721 displaced
->step_saved_copy
,
1725 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1726 original
, copy
, regcache
);
1728 /* We don't support the fully-simulated case at present. */
1729 gdb_assert (closure
);
1731 /* Save the information we need to fix things up if the step
1733 displaced
->step_ptid
= ptid
;
1734 displaced
->step_gdbarch
= gdbarch
;
1735 displaced
->step_closure
= closure
;
1736 displaced
->step_original
= original
;
1737 displaced
->step_copy
= copy
;
1739 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1741 /* Resume execution at the copy. */
1742 regcache_write_pc (regcache
, copy
);
1744 discard_cleanups (ignore_cleanups
);
1746 do_cleanups (old_cleanups
);
1748 if (debug_displaced
)
1749 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1750 paddress (gdbarch
, copy
));
1756 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1757 const gdb_byte
*myaddr
, int len
)
1759 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1761 inferior_ptid
= ptid
;
1762 write_memory (memaddr
, myaddr
, len
);
1763 do_cleanups (ptid_cleanup
);
1766 /* Restore the contents of the copy area for thread PTID. */
1769 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1772 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1774 write_memory_ptid (ptid
, displaced
->step_copy
,
1775 displaced
->step_saved_copy
, len
);
1776 if (debug_displaced
)
1777 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1778 target_pid_to_str (ptid
),
1779 paddress (displaced
->step_gdbarch
,
1780 displaced
->step_copy
));
1784 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1786 struct cleanup
*old_cleanups
;
1787 struct displaced_step_inferior_state
*displaced
1788 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1790 /* Was any thread of this process doing a displaced step? */
1791 if (displaced
== NULL
)
1794 /* Was this event for the pid we displaced? */
1795 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1796 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1799 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1801 displaced_step_restore (displaced
, displaced
->step_ptid
);
1803 /* Did the instruction complete successfully? */
1804 if (signal
== GDB_SIGNAL_TRAP
)
1806 /* Fixup may need to read memory/registers. Switch to the
1807 thread that we're fixing up. */
1808 switch_to_thread (event_ptid
);
1810 /* Fix up the resulting state. */
1811 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1812 displaced
->step_closure
,
1813 displaced
->step_original
,
1814 displaced
->step_copy
,
1815 get_thread_regcache (displaced
->step_ptid
));
1819 /* Since the instruction didn't complete, all we can do is
1821 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1822 CORE_ADDR pc
= regcache_read_pc (regcache
);
1824 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1825 regcache_write_pc (regcache
, pc
);
1828 do_cleanups (old_cleanups
);
1830 displaced
->step_ptid
= null_ptid
;
1832 /* Are there any pending displaced stepping requests? If so, run
1833 one now. Leave the state object around, since we're likely to
1834 need it again soon. */
1835 while (displaced
->step_request_queue
)
1837 struct displaced_step_request
*head
;
1839 struct regcache
*regcache
;
1840 struct gdbarch
*gdbarch
;
1841 CORE_ADDR actual_pc
;
1842 struct address_space
*aspace
;
1844 head
= displaced
->step_request_queue
;
1846 displaced
->step_request_queue
= head
->next
;
1849 context_switch (ptid
);
1851 regcache
= get_thread_regcache (ptid
);
1852 actual_pc
= regcache_read_pc (regcache
);
1853 aspace
= get_regcache_aspace (regcache
);
1855 if (breakpoint_here_p (aspace
, actual_pc
))
1857 if (debug_displaced
)
1858 fprintf_unfiltered (gdb_stdlog
,
1859 "displaced: stepping queued %s now\n",
1860 target_pid_to_str (ptid
));
1862 displaced_step_prepare (ptid
);
1864 gdbarch
= get_regcache_arch (regcache
);
1866 if (debug_displaced
)
1868 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1871 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1872 paddress (gdbarch
, actual_pc
));
1873 read_memory (actual_pc
, buf
, sizeof (buf
));
1874 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1877 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1878 displaced
->step_closure
))
1879 target_resume (ptid
, 1, GDB_SIGNAL_0
);
1881 target_resume (ptid
, 0, GDB_SIGNAL_0
);
1883 /* Done, we're stepping a thread. */
1889 struct thread_info
*tp
= inferior_thread ();
1891 /* The breakpoint we were sitting under has since been
1893 tp
->control
.trap_expected
= 0;
1895 /* Go back to what we were trying to do. */
1896 step
= currently_stepping (tp
);
1898 if (debug_displaced
)
1899 fprintf_unfiltered (gdb_stdlog
,
1900 "displaced: breakpoint is gone: %s, step(%d)\n",
1901 target_pid_to_str (tp
->ptid
), step
);
1903 target_resume (ptid
, step
, GDB_SIGNAL_0
);
1904 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
1906 /* This request was discarded. See if there's any other
1907 thread waiting for its turn. */
1912 /* Update global variables holding ptids to hold NEW_PTID if they were
1913 holding OLD_PTID. */
1915 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1917 struct displaced_step_request
*it
;
1918 struct displaced_step_inferior_state
*displaced
;
1920 if (ptid_equal (inferior_ptid
, old_ptid
))
1921 inferior_ptid
= new_ptid
;
1923 for (displaced
= displaced_step_inferior_states
;
1925 displaced
= displaced
->next
)
1927 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1928 displaced
->step_ptid
= new_ptid
;
1930 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1931 if (ptid_equal (it
->ptid
, old_ptid
))
1932 it
->ptid
= new_ptid
;
1939 /* Things to clean up if we QUIT out of resume (). */
1941 resume_cleanups (void *ignore
)
1943 if (!ptid_equal (inferior_ptid
, null_ptid
))
1944 delete_single_step_breakpoints (inferior_thread ());
1949 static const char schedlock_off
[] = "off";
1950 static const char schedlock_on
[] = "on";
1951 static const char schedlock_step
[] = "step";
1952 static const char *const scheduler_enums
[] = {
1958 static const char *scheduler_mode
= schedlock_off
;
1960 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1961 struct cmd_list_element
*c
, const char *value
)
1963 fprintf_filtered (file
,
1964 _("Mode for locking scheduler "
1965 "during execution is \"%s\".\n"),
1970 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1972 if (!target_can_lock_scheduler
)
1974 scheduler_mode
= schedlock_off
;
1975 error (_("Target '%s' cannot support this command."), target_shortname
);
1979 /* True if execution commands resume all threads of all processes by
1980 default; otherwise, resume only threads of the current inferior
1982 int sched_multi
= 0;
1984 /* Try to setup for software single stepping over the specified location.
1985 Return 1 if target_resume() should use hardware single step.
1987 GDBARCH the current gdbarch.
1988 PC the location to step over. */
1991 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1995 if (execution_direction
== EXEC_FORWARD
1996 && gdbarch_software_single_step_p (gdbarch
)
1997 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
2005 user_visible_resume_ptid (int step
)
2007 /* By default, resume all threads of all processes. */
2008 ptid_t resume_ptid
= RESUME_ALL
;
2010 /* Maybe resume only all threads of the current process. */
2011 if (!sched_multi
&& target_supports_multi_process ())
2013 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2016 /* Maybe resume a single thread after all. */
2019 /* With non-stop mode on, threads are always handled
2021 resume_ptid
= inferior_ptid
;
2023 else if ((scheduler_mode
== schedlock_on
)
2024 || (scheduler_mode
== schedlock_step
&& step
))
2026 /* User-settable 'scheduler' mode requires solo thread resume. */
2027 resume_ptid
= inferior_ptid
;
2030 /* We may actually resume fewer threads at first, e.g., if a thread
2031 is stopped at a breakpoint that needs stepping-off, but that
2032 should not be visible to the user/frontend, and neither should
2033 the frontend/user be allowed to proceed any of the threads that
2034 happen to be stopped for internal run control handling, if a
2035 previous command wanted them resumed. */
2039 /* Resume the inferior, but allow a QUIT. This is useful if the user
2040 wants to interrupt some lengthy single-stepping operation
2041 (for child processes, the SIGINT goes to the inferior, and so
2042 we get a SIGINT random_signal, but for remote debugging and perhaps
2043 other targets, that's not true).
2045 STEP nonzero if we should step (zero to continue instead).
2046 SIG is the signal to give the inferior (zero for none). */
2048 resume (int step
, enum gdb_signal sig
)
2050 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
2051 struct regcache
*regcache
= get_current_regcache ();
2052 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2053 struct thread_info
*tp
= inferior_thread ();
2054 CORE_ADDR pc
= regcache_read_pc (regcache
);
2055 struct address_space
*aspace
= get_regcache_aspace (regcache
);
2057 /* From here on, this represents the caller's step vs continue
2058 request, while STEP represents what we'll actually request the
2059 target to do. STEP can decay from a step to a continue, if e.g.,
2060 we need to implement single-stepping with breakpoints (software
2061 single-step). When deciding whether "set scheduler-locking step"
2062 applies, it's the callers intention that counts. */
2063 const int entry_step
= step
;
2065 tp
->stepped_breakpoint
= 0;
2069 if (current_inferior ()->waiting_for_vfork_done
)
2071 /* Don't try to single-step a vfork parent that is waiting for
2072 the child to get out of the shared memory region (by exec'ing
2073 or exiting). This is particularly important on software
2074 single-step archs, as the child process would trip on the
2075 software single step breakpoint inserted for the parent
2076 process. Since the parent will not actually execute any
2077 instruction until the child is out of the shared region (such
2078 are vfork's semantics), it is safe to simply continue it.
2079 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2080 the parent, and tell it to `keep_going', which automatically
2081 re-sets it stepping. */
2083 fprintf_unfiltered (gdb_stdlog
,
2084 "infrun: resume : clear step\n");
2089 fprintf_unfiltered (gdb_stdlog
,
2090 "infrun: resume (step=%d, signal=%s), "
2091 "trap_expected=%d, current thread [%s] at %s\n",
2092 step
, gdb_signal_to_symbol_string (sig
),
2093 tp
->control
.trap_expected
,
2094 target_pid_to_str (inferior_ptid
),
2095 paddress (gdbarch
, pc
));
2097 /* Normally, by the time we reach `resume', the breakpoints are either
2098 removed or inserted, as appropriate. The exception is if we're sitting
2099 at a permanent breakpoint; we need to step over it, but permanent
2100 breakpoints can't be removed. So we have to test for it here. */
2101 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2103 if (sig
!= GDB_SIGNAL_0
)
2105 /* We have a signal to pass to the inferior. The resume
2106 may, or may not take us to the signal handler. If this
2107 is a step, we'll need to stop in the signal handler, if
2108 there's one, (if the target supports stepping into
2109 handlers), or in the next mainline instruction, if
2110 there's no handler. If this is a continue, we need to be
2111 sure to run the handler with all breakpoints inserted.
2112 In all cases, set a breakpoint at the current address
2113 (where the handler returns to), and once that breakpoint
2114 is hit, resume skipping the permanent breakpoint. If
2115 that breakpoint isn't hit, then we've stepped into the
2116 signal handler (or hit some other event). We'll delete
2117 the step-resume breakpoint then. */
2120 fprintf_unfiltered (gdb_stdlog
,
2121 "infrun: resume: skipping permanent breakpoint, "
2122 "deliver signal first\n");
2124 clear_step_over_info ();
2125 tp
->control
.trap_expected
= 0;
2127 if (tp
->control
.step_resume_breakpoint
== NULL
)
2129 /* Set a "high-priority" step-resume, as we don't want
2130 user breakpoints at PC to trigger (again) when this
2132 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2133 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2135 tp
->step_after_step_resume_breakpoint
= step
;
2138 insert_breakpoints ();
2142 /* There's no signal to pass, we can go ahead and skip the
2143 permanent breakpoint manually. */
2145 fprintf_unfiltered (gdb_stdlog
,
2146 "infrun: resume: skipping permanent breakpoint\n");
2147 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2148 /* Update pc to reflect the new address from which we will
2149 execute instructions. */
2150 pc
= regcache_read_pc (regcache
);
2154 /* We've already advanced the PC, so the stepping part
2155 is done. Now we need to arrange for a trap to be
2156 reported to handle_inferior_event. Set a breakpoint
2157 at the current PC, and run to it. Don't update
2158 prev_pc, because if we end in
2159 switch_back_to_stepping, we want the "expected thread
2160 advanced also" branch to be taken. IOW, we don't
2161 want this thread to step further from PC
2163 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2164 insert_breakpoints ();
2166 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2167 /* We're continuing with all breakpoints inserted. It's
2168 safe to let the target bypass signals. */
2169 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2170 /* ... and safe to let other threads run, according to
2172 resume_ptid
= user_visible_resume_ptid (entry_step
);
2173 target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2174 discard_cleanups (old_cleanups
);
2180 /* If we have a breakpoint to step over, make sure to do a single
2181 step only. Same if we have software watchpoints. */
2182 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2183 tp
->control
.may_range_step
= 0;
2185 /* If enabled, step over breakpoints by executing a copy of the
2186 instruction at a different address.
2188 We can't use displaced stepping when we have a signal to deliver;
2189 the comments for displaced_step_prepare explain why. The
2190 comments in the handle_inferior event for dealing with 'random
2191 signals' explain what we do instead.
2193 We can't use displaced stepping when we are waiting for vfork_done
2194 event, displaced stepping breaks the vfork child similarly as single
2195 step software breakpoint. */
2196 if (use_displaced_stepping (gdbarch
)
2197 && tp
->control
.trap_expected
2198 && sig
== GDB_SIGNAL_0
2199 && !current_inferior ()->waiting_for_vfork_done
)
2201 struct displaced_step_inferior_state
*displaced
;
2203 if (!displaced_step_prepare (inferior_ptid
))
2205 /* Got placed in displaced stepping queue. Will be resumed
2206 later when all the currently queued displaced stepping
2207 requests finish. The thread is not executing at this
2208 point, and the call to set_executing will be made later.
2209 But we need to call set_running here, since from the
2210 user/frontend's point of view, threads were set running.
2211 Unless we're calling an inferior function, as in that
2212 case we pretend the inferior doesn't run at all. */
2213 if (!tp
->control
.in_infcall
)
2214 set_running (user_visible_resume_ptid (entry_step
), 1);
2215 discard_cleanups (old_cleanups
);
2219 /* Update pc to reflect the new address from which we will execute
2220 instructions due to displaced stepping. */
2221 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2223 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2224 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2225 displaced
->step_closure
);
2228 /* Do we need to do it the hard way, w/temp breakpoints? */
2230 step
= maybe_software_singlestep (gdbarch
, pc
);
2232 /* Currently, our software single-step implementation leads to different
2233 results than hardware single-stepping in one situation: when stepping
2234 into delivering a signal which has an associated signal handler,
2235 hardware single-step will stop at the first instruction of the handler,
2236 while software single-step will simply skip execution of the handler.
2238 For now, this difference in behavior is accepted since there is no
2239 easy way to actually implement single-stepping into a signal handler
2240 without kernel support.
2242 However, there is one scenario where this difference leads to follow-on
2243 problems: if we're stepping off a breakpoint by removing all breakpoints
2244 and then single-stepping. In this case, the software single-step
2245 behavior means that even if there is a *breakpoint* in the signal
2246 handler, GDB still would not stop.
2248 Fortunately, we can at least fix this particular issue. We detect
2249 here the case where we are about to deliver a signal while software
2250 single-stepping with breakpoints removed. In this situation, we
2251 revert the decisions to remove all breakpoints and insert single-
2252 step breakpoints, and instead we install a step-resume breakpoint
2253 at the current address, deliver the signal without stepping, and
2254 once we arrive back at the step-resume breakpoint, actually step
2255 over the breakpoint we originally wanted to step over. */
2256 if (thread_has_single_step_breakpoints_set (tp
)
2257 && sig
!= GDB_SIGNAL_0
2258 && step_over_info_valid_p ())
2260 /* If we have nested signals or a pending signal is delivered
2261 immediately after a handler returns, might might already have
2262 a step-resume breakpoint set on the earlier handler. We cannot
2263 set another step-resume breakpoint; just continue on until the
2264 original breakpoint is hit. */
2265 if (tp
->control
.step_resume_breakpoint
== NULL
)
2267 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2268 tp
->step_after_step_resume_breakpoint
= 1;
2271 delete_single_step_breakpoints (tp
);
2273 clear_step_over_info ();
2274 tp
->control
.trap_expected
= 0;
2276 insert_breakpoints ();
2279 /* If STEP is set, it's a request to use hardware stepping
2280 facilities. But in that case, we should never
2281 use singlestep breakpoint. */
2282 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2284 /* Decide the set of threads to ask the target to resume. Start
2285 by assuming everything will be resumed, than narrow the set
2286 by applying increasingly restricting conditions. */
2287 resume_ptid
= user_visible_resume_ptid (entry_step
);
2289 /* Even if RESUME_PTID is a wildcard, and we end up resuming less
2290 (e.g., we might need to step over a breakpoint), from the
2291 user/frontend's point of view, all threads in RESUME_PTID are now
2292 running. Unless we're calling an inferior function, as in that
2293 case pretend we inferior doesn't run at all. */
2294 if (!tp
->control
.in_infcall
)
2295 set_running (resume_ptid
, 1);
2297 /* Maybe resume a single thread after all. */
2298 if ((step
|| thread_has_single_step_breakpoints_set (tp
))
2299 && tp
->control
.trap_expected
)
2301 /* We're allowing a thread to run past a breakpoint it has
2302 hit, by single-stepping the thread with the breakpoint
2303 removed. In which case, we need to single-step only this
2304 thread, and keep others stopped, as they can miss this
2305 breakpoint if allowed to run. */
2306 resume_ptid
= inferior_ptid
;
2309 if (execution_direction
!= EXEC_REVERSE
2310 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2312 /* The only case we currently need to step a breakpoint
2313 instruction is when we have a signal to deliver. See
2314 handle_signal_stop where we handle random signals that could
2315 take out us out of the stepping range. Normally, in that
2316 case we end up continuing (instead of stepping) over the
2317 signal handler with a breakpoint at PC, but there are cases
2318 where we should _always_ single-step, even if we have a
2319 step-resume breakpoint, like when a software watchpoint is
2320 set. Assuming single-stepping and delivering a signal at the
2321 same time would takes us to the signal handler, then we could
2322 have removed the breakpoint at PC to step over it. However,
2323 some hardware step targets (like e.g., Mac OS) can't step
2324 into signal handlers, and for those, we need to leave the
2325 breakpoint at PC inserted, as otherwise if the handler
2326 recurses and executes PC again, it'll miss the breakpoint.
2327 So we leave the breakpoint inserted anyway, but we need to
2328 record that we tried to step a breakpoint instruction, so
2329 that adjust_pc_after_break doesn't end up confused. */
2330 gdb_assert (sig
!= GDB_SIGNAL_0
);
2332 tp
->stepped_breakpoint
= 1;
2334 /* Most targets can step a breakpoint instruction, thus
2335 executing it normally. But if this one cannot, just
2336 continue and we will hit it anyway. */
2337 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2342 && use_displaced_stepping (gdbarch
)
2343 && tp
->control
.trap_expected
)
2345 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
2346 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
2347 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2350 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2351 paddress (resume_gdbarch
, actual_pc
));
2352 read_memory (actual_pc
, buf
, sizeof (buf
));
2353 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2356 if (tp
->control
.may_range_step
)
2358 /* If we're resuming a thread with the PC out of the step
2359 range, then we're doing some nested/finer run control
2360 operation, like stepping the thread out of the dynamic
2361 linker or the displaced stepping scratch pad. We
2362 shouldn't have allowed a range step then. */
2363 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2366 /* Install inferior's terminal modes. */
2367 target_terminal_inferior ();
2369 /* Avoid confusing the next resume, if the next stop/resume
2370 happens to apply to another thread. */
2371 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2373 /* Advise target which signals may be handled silently. If we have
2374 removed breakpoints because we are stepping over one (in any
2375 thread), we need to receive all signals to avoid accidentally
2376 skipping a breakpoint during execution of a signal handler. */
2377 if (step_over_info_valid_p ())
2378 target_pass_signals (0, NULL
);
2380 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2382 target_resume (resume_ptid
, step
, sig
);
2384 discard_cleanups (old_cleanups
);
2389 /* Clear out all variables saying what to do when inferior is continued.
2390 First do this, then set the ones you want, then call `proceed'. */
2393 clear_proceed_status_thread (struct thread_info
*tp
)
2396 fprintf_unfiltered (gdb_stdlog
,
2397 "infrun: clear_proceed_status_thread (%s)\n",
2398 target_pid_to_str (tp
->ptid
));
2400 /* If this signal should not be seen by program, give it zero.
2401 Used for debugging signals. */
2402 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2403 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2405 tp
->control
.trap_expected
= 0;
2406 tp
->control
.step_range_start
= 0;
2407 tp
->control
.step_range_end
= 0;
2408 tp
->control
.may_range_step
= 0;
2409 tp
->control
.step_frame_id
= null_frame_id
;
2410 tp
->control
.step_stack_frame_id
= null_frame_id
;
2411 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2412 tp
->stop_requested
= 0;
2414 tp
->control
.stop_step
= 0;
2416 tp
->control
.proceed_to_finish
= 0;
2418 tp
->control
.command_interp
= NULL
;
2420 /* Discard any remaining commands or status from previous stop. */
2421 bpstat_clear (&tp
->control
.stop_bpstat
);
2425 clear_proceed_status (int step
)
2429 struct thread_info
*tp
;
2432 resume_ptid
= user_visible_resume_ptid (step
);
2434 /* In all-stop mode, delete the per-thread status of all threads
2435 we're about to resume, implicitly and explicitly. */
2436 ALL_NON_EXITED_THREADS (tp
)
2438 if (!ptid_match (tp
->ptid
, resume_ptid
))
2440 clear_proceed_status_thread (tp
);
2444 if (!ptid_equal (inferior_ptid
, null_ptid
))
2446 struct inferior
*inferior
;
2450 /* If in non-stop mode, only delete the per-thread status of
2451 the current thread. */
2452 clear_proceed_status_thread (inferior_thread ());
2455 inferior
= current_inferior ();
2456 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2459 stop_after_trap
= 0;
2461 clear_step_over_info ();
2463 observer_notify_about_to_proceed ();
2467 regcache_xfree (stop_registers
);
2468 stop_registers
= NULL
;
2472 /* Returns true if TP is still stopped at a breakpoint that needs
2473 stepping-over in order to make progress. If the breakpoint is gone
2474 meanwhile, we can skip the whole step-over dance. */
2477 thread_still_needs_step_over (struct thread_info
*tp
)
2479 if (tp
->stepping_over_breakpoint
)
2481 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2483 if (breakpoint_here_p (get_regcache_aspace (regcache
),
2484 regcache_read_pc (regcache
))
2485 == ordinary_breakpoint_here
)
2488 tp
->stepping_over_breakpoint
= 0;
2494 /* Returns true if scheduler locking applies. STEP indicates whether
2495 we're about to do a step/next-like command to a thread. */
2498 schedlock_applies (int step
)
2500 return (scheduler_mode
== schedlock_on
2501 || (scheduler_mode
== schedlock_step
2505 /* Look a thread other than EXCEPT that has previously reported a
2506 breakpoint event, and thus needs a step-over in order to make
2507 progress. Returns NULL is none is found. STEP indicates whether
2508 we're about to step the current thread, in order to decide whether
2509 "set scheduler-locking step" applies. */
2511 static struct thread_info
*
2512 find_thread_needs_step_over (int step
, struct thread_info
*except
)
2514 struct thread_info
*tp
, *current
;
2516 /* With non-stop mode on, threads are always handled individually. */
2517 gdb_assert (! non_stop
);
2519 current
= inferior_thread ();
2521 /* If scheduler locking applies, we can avoid iterating over all
2523 if (schedlock_applies (step
))
2525 if (except
!= current
2526 && thread_still_needs_step_over (current
))
2532 ALL_NON_EXITED_THREADS (tp
)
2534 /* Ignore the EXCEPT thread. */
2537 /* Ignore threads of processes we're not resuming. */
2539 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
2542 if (thread_still_needs_step_over (tp
))
2549 /* Basic routine for continuing the program in various fashions.
2551 ADDR is the address to resume at, or -1 for resume where stopped.
2552 SIGGNAL is the signal to give it, or 0 for none,
2553 or -1 for act according to how it stopped.
2554 STEP is nonzero if should trap after one instruction.
2555 -1 means return after that and print nothing.
2556 You should probably set various step_... variables
2557 before calling here, if you are stepping.
2559 You should call clear_proceed_status before calling proceed. */
2562 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
, int step
)
2564 struct regcache
*regcache
;
2565 struct gdbarch
*gdbarch
;
2566 struct thread_info
*tp
;
2568 struct address_space
*aspace
;
2570 /* If we're stopped at a fork/vfork, follow the branch set by the
2571 "set follow-fork-mode" command; otherwise, we'll just proceed
2572 resuming the current thread. */
2573 if (!follow_fork ())
2575 /* The target for some reason decided not to resume. */
2577 if (target_can_async_p ())
2578 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2582 /* We'll update this if & when we switch to a new thread. */
2583 previous_inferior_ptid
= inferior_ptid
;
2585 regcache
= get_current_regcache ();
2586 gdbarch
= get_regcache_arch (regcache
);
2587 aspace
= get_regcache_aspace (regcache
);
2588 pc
= regcache_read_pc (regcache
);
2589 tp
= inferior_thread ();
2592 step_start_function
= find_pc_function (pc
);
2594 stop_after_trap
= 1;
2596 /* Fill in with reasonable starting values. */
2597 init_thread_stepping_state (tp
);
2599 if (addr
== (CORE_ADDR
) -1)
2602 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
2603 && execution_direction
!= EXEC_REVERSE
)
2604 /* There is a breakpoint at the address we will resume at,
2605 step one instruction before inserting breakpoints so that
2606 we do not stop right away (and report a second hit at this
2609 Note, we don't do this in reverse, because we won't
2610 actually be executing the breakpoint insn anyway.
2611 We'll be (un-)executing the previous instruction. */
2612 tp
->stepping_over_breakpoint
= 1;
2613 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2614 && gdbarch_single_step_through_delay (gdbarch
,
2615 get_current_frame ()))
2616 /* We stepped onto an instruction that needs to be stepped
2617 again before re-inserting the breakpoint, do so. */
2618 tp
->stepping_over_breakpoint
= 1;
2622 regcache_write_pc (regcache
, addr
);
2625 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2626 tp
->suspend
.stop_signal
= siggnal
;
2628 /* Record the interpreter that issued the execution command that
2629 caused this thread to resume. If the top level interpreter is
2630 MI/async, and the execution command was a CLI command
2631 (next/step/etc.), we'll want to print stop event output to the MI
2632 console channel (the stepped-to line, etc.), as if the user
2633 entered the execution command on a real GDB console. */
2634 inferior_thread ()->control
.command_interp
= command_interp ();
2637 fprintf_unfiltered (gdb_stdlog
,
2638 "infrun: proceed (addr=%s, signal=%s, step=%d)\n",
2639 paddress (gdbarch
, addr
),
2640 gdb_signal_to_symbol_string (siggnal
), step
);
2643 /* In non-stop, each thread is handled individually. The context
2644 must already be set to the right thread here. */
2648 struct thread_info
*step_over
;
2650 /* In a multi-threaded task we may select another thread and
2651 then continue or step.
2653 But if the old thread was stopped at a breakpoint, it will
2654 immediately cause another breakpoint stop without any
2655 execution (i.e. it will report a breakpoint hit incorrectly).
2656 So we must step over it first.
2658 Look for a thread other than the current (TP) that reported a
2659 breakpoint hit and hasn't been resumed yet since. */
2660 step_over
= find_thread_needs_step_over (step
, tp
);
2661 if (step_over
!= NULL
)
2664 fprintf_unfiltered (gdb_stdlog
,
2665 "infrun: need to step-over [%s] first\n",
2666 target_pid_to_str (step_over
->ptid
));
2668 /* Store the prev_pc for the stepping thread too, needed by
2669 switch_back_to_stepping thread. */
2670 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2671 switch_to_thread (step_over
->ptid
);
2676 /* If we need to step over a breakpoint, and we're not using
2677 displaced stepping to do so, insert all breakpoints (watchpoints,
2678 etc.) but the one we're stepping over, step one instruction, and
2679 then re-insert the breakpoint when that step is finished. */
2680 if (tp
->stepping_over_breakpoint
&& !use_displaced_stepping (gdbarch
))
2682 struct regcache
*regcache
= get_current_regcache ();
2684 set_step_over_info (get_regcache_aspace (regcache
),
2685 regcache_read_pc (regcache
), 0);
2688 clear_step_over_info ();
2690 insert_breakpoints ();
2692 tp
->control
.trap_expected
= tp
->stepping_over_breakpoint
;
2694 annotate_starting ();
2696 /* Make sure that output from GDB appears before output from the
2698 gdb_flush (gdb_stdout
);
2700 /* Refresh prev_pc value just prior to resuming. This used to be
2701 done in stop_waiting, however, setting prev_pc there did not handle
2702 scenarios such as inferior function calls or returning from
2703 a function via the return command. In those cases, the prev_pc
2704 value was not set properly for subsequent commands. The prev_pc value
2705 is used to initialize the starting line number in the ecs. With an
2706 invalid value, the gdb next command ends up stopping at the position
2707 represented by the next line table entry past our start position.
2708 On platforms that generate one line table entry per line, this
2709 is not a problem. However, on the ia64, the compiler generates
2710 extraneous line table entries that do not increase the line number.
2711 When we issue the gdb next command on the ia64 after an inferior call
2712 or a return command, we often end up a few instructions forward, still
2713 within the original line we started.
2715 An attempt was made to refresh the prev_pc at the same time the
2716 execution_control_state is initialized (for instance, just before
2717 waiting for an inferior event). But this approach did not work
2718 because of platforms that use ptrace, where the pc register cannot
2719 be read unless the inferior is stopped. At that point, we are not
2720 guaranteed the inferior is stopped and so the regcache_read_pc() call
2721 can fail. Setting the prev_pc value here ensures the value is updated
2722 correctly when the inferior is stopped. */
2723 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2725 /* Resume inferior. */
2726 resume (tp
->control
.trap_expected
|| step
|| bpstat_should_step (),
2727 tp
->suspend
.stop_signal
);
2729 /* Wait for it to stop (if not standalone)
2730 and in any case decode why it stopped, and act accordingly. */
2731 /* Do this only if we are not using the event loop, or if the target
2732 does not support asynchronous execution. */
2733 if (!target_can_async_p ())
2735 wait_for_inferior ();
2741 /* Start remote-debugging of a machine over a serial link. */
2744 start_remote (int from_tty
)
2746 struct inferior
*inferior
;
2748 inferior
= current_inferior ();
2749 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2751 /* Always go on waiting for the target, regardless of the mode. */
2752 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2753 indicate to wait_for_inferior that a target should timeout if
2754 nothing is returned (instead of just blocking). Because of this,
2755 targets expecting an immediate response need to, internally, set
2756 things up so that the target_wait() is forced to eventually
2758 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2759 differentiate to its caller what the state of the target is after
2760 the initial open has been performed. Here we're assuming that
2761 the target has stopped. It should be possible to eventually have
2762 target_open() return to the caller an indication that the target
2763 is currently running and GDB state should be set to the same as
2764 for an async run. */
2765 wait_for_inferior ();
2767 /* Now that the inferior has stopped, do any bookkeeping like
2768 loading shared libraries. We want to do this before normal_stop,
2769 so that the displayed frame is up to date. */
2770 post_create_inferior (¤t_target
, from_tty
);
2775 /* Initialize static vars when a new inferior begins. */
2778 init_wait_for_inferior (void)
2780 /* These are meaningless until the first time through wait_for_inferior. */
2782 breakpoint_init_inferior (inf_starting
);
2784 clear_proceed_status (0);
2786 target_last_wait_ptid
= minus_one_ptid
;
2788 previous_inferior_ptid
= inferior_ptid
;
2790 /* Discard any skipped inlined frames. */
2791 clear_inline_frame_state (minus_one_ptid
);
2795 /* Data to be passed around while handling an event. This data is
2796 discarded between events. */
2797 struct execution_control_state
2800 /* The thread that got the event, if this was a thread event; NULL
2802 struct thread_info
*event_thread
;
2804 struct target_waitstatus ws
;
2805 int stop_func_filled_in
;
2806 CORE_ADDR stop_func_start
;
2807 CORE_ADDR stop_func_end
;
2808 const char *stop_func_name
;
2811 /* True if the event thread hit the single-step breakpoint of
2812 another thread. Thus the event doesn't cause a stop, the thread
2813 needs to be single-stepped past the single-step breakpoint before
2814 we can switch back to the original stepping thread. */
2815 int hit_singlestep_breakpoint
;
2818 static void handle_inferior_event (struct execution_control_state
*ecs
);
2820 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2821 struct execution_control_state
*ecs
);
2822 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2823 struct execution_control_state
*ecs
);
2824 static void handle_signal_stop (struct execution_control_state
*ecs
);
2825 static void check_exception_resume (struct execution_control_state
*,
2826 struct frame_info
*);
2828 static void end_stepping_range (struct execution_control_state
*ecs
);
2829 static void stop_waiting (struct execution_control_state
*ecs
);
2830 static void prepare_to_wait (struct execution_control_state
*ecs
);
2831 static void keep_going (struct execution_control_state
*ecs
);
2832 static void process_event_stop_test (struct execution_control_state
*ecs
);
2833 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
2835 /* Callback for iterate over threads. If the thread is stopped, but
2836 the user/frontend doesn't know about that yet, go through
2837 normal_stop, as if the thread had just stopped now. ARG points at
2838 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2839 ptid_is_pid(PTID) is true, applies to all threads of the process
2840 pointed at by PTID. Otherwise, apply only to the thread pointed by
2844 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2846 ptid_t ptid
= * (ptid_t
*) arg
;
2848 if ((ptid_equal (info
->ptid
, ptid
)
2849 || ptid_equal (minus_one_ptid
, ptid
)
2850 || (ptid_is_pid (ptid
)
2851 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2852 && is_running (info
->ptid
)
2853 && !is_executing (info
->ptid
))
2855 struct cleanup
*old_chain
;
2856 struct execution_control_state ecss
;
2857 struct execution_control_state
*ecs
= &ecss
;
2859 memset (ecs
, 0, sizeof (*ecs
));
2861 old_chain
= make_cleanup_restore_current_thread ();
2863 overlay_cache_invalid
= 1;
2864 /* Flush target cache before starting to handle each event.
2865 Target was running and cache could be stale. This is just a
2866 heuristic. Running threads may modify target memory, but we
2867 don't get any event. */
2868 target_dcache_invalidate ();
2870 /* Go through handle_inferior_event/normal_stop, so we always
2871 have consistent output as if the stop event had been
2873 ecs
->ptid
= info
->ptid
;
2874 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2875 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2876 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
2878 handle_inferior_event (ecs
);
2880 if (!ecs
->wait_some_more
)
2882 struct thread_info
*tp
;
2886 /* Finish off the continuations. */
2887 tp
= inferior_thread ();
2888 do_all_intermediate_continuations_thread (tp
, 1);
2889 do_all_continuations_thread (tp
, 1);
2892 do_cleanups (old_chain
);
2898 /* This function is attached as a "thread_stop_requested" observer.
2899 Cleanup local state that assumed the PTID was to be resumed, and
2900 report the stop to the frontend. */
2903 infrun_thread_stop_requested (ptid_t ptid
)
2905 struct displaced_step_inferior_state
*displaced
;
2907 /* PTID was requested to stop. Remove it from the displaced
2908 stepping queue, so we don't try to resume it automatically. */
2910 for (displaced
= displaced_step_inferior_states
;
2912 displaced
= displaced
->next
)
2914 struct displaced_step_request
*it
, **prev_next_p
;
2916 it
= displaced
->step_request_queue
;
2917 prev_next_p
= &displaced
->step_request_queue
;
2920 if (ptid_match (it
->ptid
, ptid
))
2922 *prev_next_p
= it
->next
;
2928 prev_next_p
= &it
->next
;
2935 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2939 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2941 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2942 nullify_last_target_wait_ptid ();
2945 /* Delete the step resume, single-step and longjmp/exception resume
2946 breakpoints of TP. */
2949 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
2951 delete_step_resume_breakpoint (tp
);
2952 delete_exception_resume_breakpoint (tp
);
2953 delete_single_step_breakpoints (tp
);
2956 /* If the target still has execution, call FUNC for each thread that
2957 just stopped. In all-stop, that's all the non-exited threads; in
2958 non-stop, that's the current thread, only. */
2960 typedef void (*for_each_just_stopped_thread_callback_func
)
2961 (struct thread_info
*tp
);
2964 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
2966 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
2971 /* If in non-stop mode, only the current thread stopped. */
2972 func (inferior_thread ());
2976 struct thread_info
*tp
;
2978 /* In all-stop mode, all threads have stopped. */
2979 ALL_NON_EXITED_THREADS (tp
)
2986 /* Delete the step resume and longjmp/exception resume breakpoints of
2987 the threads that just stopped. */
2990 delete_just_stopped_threads_infrun_breakpoints (void)
2992 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
2995 /* Delete the single-step breakpoints of the threads that just
2999 delete_just_stopped_threads_single_step_breakpoints (void)
3001 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3004 /* A cleanup wrapper. */
3007 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3009 delete_just_stopped_threads_infrun_breakpoints ();
3012 /* Pretty print the results of target_wait, for debugging purposes. */
3015 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3016 const struct target_waitstatus
*ws
)
3018 char *status_string
= target_waitstatus_to_string (ws
);
3019 struct ui_file
*tmp_stream
= mem_fileopen ();
3022 /* The text is split over several lines because it was getting too long.
3023 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3024 output as a unit; we want only one timestamp printed if debug_timestamp
3027 fprintf_unfiltered (tmp_stream
,
3028 "infrun: target_wait (%d", ptid_get_pid (waiton_ptid
));
3029 if (ptid_get_pid (waiton_ptid
) != -1)
3030 fprintf_unfiltered (tmp_stream
,
3031 " [%s]", target_pid_to_str (waiton_ptid
));
3032 fprintf_unfiltered (tmp_stream
, ", status) =\n");
3033 fprintf_unfiltered (tmp_stream
,
3034 "infrun: %d [%s],\n",
3035 ptid_get_pid (result_ptid
),
3036 target_pid_to_str (result_ptid
));
3037 fprintf_unfiltered (tmp_stream
,
3041 text
= ui_file_xstrdup (tmp_stream
, NULL
);
3043 /* This uses %s in part to handle %'s in the text, but also to avoid
3044 a gcc error: the format attribute requires a string literal. */
3045 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
3047 xfree (status_string
);
3049 ui_file_delete (tmp_stream
);
3052 /* Prepare and stabilize the inferior for detaching it. E.g.,
3053 detaching while a thread is displaced stepping is a recipe for
3054 crashing it, as nothing would readjust the PC out of the scratch
3058 prepare_for_detach (void)
3060 struct inferior
*inf
= current_inferior ();
3061 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3062 struct cleanup
*old_chain_1
;
3063 struct displaced_step_inferior_state
*displaced
;
3065 displaced
= get_displaced_stepping_state (inf
->pid
);
3067 /* Is any thread of this process displaced stepping? If not,
3068 there's nothing else to do. */
3069 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3073 fprintf_unfiltered (gdb_stdlog
,
3074 "displaced-stepping in-process while detaching");
3076 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
3079 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3081 struct cleanup
*old_chain_2
;
3082 struct execution_control_state ecss
;
3083 struct execution_control_state
*ecs
;
3086 memset (ecs
, 0, sizeof (*ecs
));
3088 overlay_cache_invalid
= 1;
3089 /* Flush target cache before starting to handle each event.
3090 Target was running and cache could be stale. This is just a
3091 heuristic. Running threads may modify target memory, but we
3092 don't get any event. */
3093 target_dcache_invalidate ();
3095 if (deprecated_target_wait_hook
)
3096 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
3098 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
3101 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3103 /* If an error happens while handling the event, propagate GDB's
3104 knowledge of the executing state to the frontend/user running
3106 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3109 /* Now figure out what to do with the result of the result. */
3110 handle_inferior_event (ecs
);
3112 /* No error, don't finish the state yet. */
3113 discard_cleanups (old_chain_2
);
3115 /* Breakpoints and watchpoints are not installed on the target
3116 at this point, and signals are passed directly to the
3117 inferior, so this must mean the process is gone. */
3118 if (!ecs
->wait_some_more
)
3120 discard_cleanups (old_chain_1
);
3121 error (_("Program exited while detaching"));
3125 discard_cleanups (old_chain_1
);
3128 /* Wait for control to return from inferior to debugger.
3130 If inferior gets a signal, we may decide to start it up again
3131 instead of returning. That is why there is a loop in this function.
3132 When this function actually returns it means the inferior
3133 should be left stopped and GDB should read more commands. */
3136 wait_for_inferior (void)
3138 struct cleanup
*old_cleanups
;
3142 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3145 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3150 struct execution_control_state ecss
;
3151 struct execution_control_state
*ecs
= &ecss
;
3152 struct cleanup
*old_chain
;
3153 ptid_t waiton_ptid
= minus_one_ptid
;
3155 memset (ecs
, 0, sizeof (*ecs
));
3157 overlay_cache_invalid
= 1;
3159 /* Flush target cache before starting to handle each event.
3160 Target was running and cache could be stale. This is just a
3161 heuristic. Running threads may modify target memory, but we
3162 don't get any event. */
3163 target_dcache_invalidate ();
3165 if (deprecated_target_wait_hook
)
3166 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
3168 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
3171 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3173 /* If an error happens while handling the event, propagate GDB's
3174 knowledge of the executing state to the frontend/user running
3176 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3178 /* Now figure out what to do with the result of the result. */
3179 handle_inferior_event (ecs
);
3181 /* No error, don't finish the state yet. */
3182 discard_cleanups (old_chain
);
3184 if (!ecs
->wait_some_more
)
3188 do_cleanups (old_cleanups
);
3191 /* Cleanup that reinstalls the readline callback handler, if the
3192 target is running in the background. If while handling the target
3193 event something triggered a secondary prompt, like e.g., a
3194 pagination prompt, we'll have removed the callback handler (see
3195 gdb_readline_wrapper_line). Need to do this as we go back to the
3196 event loop, ready to process further input. Note this has no
3197 effect if the handler hasn't actually been removed, because calling
3198 rl_callback_handler_install resets the line buffer, thus losing
3202 reinstall_readline_callback_handler_cleanup (void *arg
)
3204 if (!interpreter_async
)
3206 /* We're not going back to the top level event loop yet. Don't
3207 install the readline callback, as it'd prep the terminal,
3208 readline-style (raw, noecho) (e.g., --batch). We'll install
3209 it the next time the prompt is displayed, when we're ready
3214 if (async_command_editing_p
&& !sync_execution
)
3215 gdb_rl_callback_handler_reinstall ();
3218 /* Asynchronous version of wait_for_inferior. It is called by the
3219 event loop whenever a change of state is detected on the file
3220 descriptor corresponding to the target. It can be called more than
3221 once to complete a single execution command. In such cases we need
3222 to keep the state in a global variable ECSS. If it is the last time
3223 that this function is called for a single execution command, then
3224 report to the user that the inferior has stopped, and do the
3225 necessary cleanups. */
3228 fetch_inferior_event (void *client_data
)
3230 struct execution_control_state ecss
;
3231 struct execution_control_state
*ecs
= &ecss
;
3232 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3233 struct cleanup
*ts_old_chain
;
3234 int was_sync
= sync_execution
;
3236 ptid_t waiton_ptid
= minus_one_ptid
;
3238 memset (ecs
, 0, sizeof (*ecs
));
3240 /* End up with readline processing input, if necessary. */
3241 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3243 /* We're handling a live event, so make sure we're doing live
3244 debugging. If we're looking at traceframes while the target is
3245 running, we're going to need to get back to that mode after
3246 handling the event. */
3249 make_cleanup_restore_current_traceframe ();
3250 set_current_traceframe (-1);
3254 /* In non-stop mode, the user/frontend should not notice a thread
3255 switch due to internal events. Make sure we reverse to the
3256 user selected thread and frame after handling the event and
3257 running any breakpoint commands. */
3258 make_cleanup_restore_current_thread ();
3260 overlay_cache_invalid
= 1;
3261 /* Flush target cache before starting to handle each event. Target
3262 was running and cache could be stale. This is just a heuristic.
3263 Running threads may modify target memory, but we don't get any
3265 target_dcache_invalidate ();
3267 make_cleanup_restore_integer (&execution_direction
);
3268 execution_direction
= target_execution_direction ();
3270 if (deprecated_target_wait_hook
)
3272 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3274 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
3277 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3279 /* If an error happens while handling the event, propagate GDB's
3280 knowledge of the executing state to the frontend/user running
3283 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3285 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3287 /* Get executed before make_cleanup_restore_current_thread above to apply
3288 still for the thread which has thrown the exception. */
3289 make_bpstat_clear_actions_cleanup ();
3291 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3293 /* Now figure out what to do with the result of the result. */
3294 handle_inferior_event (ecs
);
3296 if (!ecs
->wait_some_more
)
3298 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3300 delete_just_stopped_threads_infrun_breakpoints ();
3302 /* We may not find an inferior if this was a process exit. */
3303 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3306 if (target_has_execution
3307 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
3308 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3309 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3310 && ecs
->event_thread
->step_multi
3311 && ecs
->event_thread
->control
.stop_step
)
3312 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
3315 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3320 /* No error, don't finish the thread states yet. */
3321 discard_cleanups (ts_old_chain
);
3323 /* Revert thread and frame. */
3324 do_cleanups (old_chain
);
3326 /* If the inferior was in sync execution mode, and now isn't,
3327 restore the prompt (a synchronous execution command has finished,
3328 and we're ready for input). */
3329 if (interpreter_async
&& was_sync
&& !sync_execution
)
3330 observer_notify_sync_execution_done ();
3334 && exec_done_display_p
3335 && (ptid_equal (inferior_ptid
, null_ptid
)
3336 || !is_running (inferior_ptid
)))
3337 printf_unfiltered (_("completed.\n"));
3340 /* Record the frame and location we're currently stepping through. */
3342 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3344 struct thread_info
*tp
= inferior_thread ();
3346 tp
->control
.step_frame_id
= get_frame_id (frame
);
3347 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3349 tp
->current_symtab
= sal
.symtab
;
3350 tp
->current_line
= sal
.line
;
3353 /* Clear context switchable stepping state. */
3356 init_thread_stepping_state (struct thread_info
*tss
)
3358 tss
->stepped_breakpoint
= 0;
3359 tss
->stepping_over_breakpoint
= 0;
3360 tss
->stepping_over_watchpoint
= 0;
3361 tss
->step_after_step_resume_breakpoint
= 0;
3364 /* Set the cached copy of the last ptid/waitstatus. */
3367 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3369 target_last_wait_ptid
= ptid
;
3370 target_last_waitstatus
= status
;
3373 /* Return the cached copy of the last pid/waitstatus returned by
3374 target_wait()/deprecated_target_wait_hook(). The data is actually
3375 cached by handle_inferior_event(), which gets called immediately
3376 after target_wait()/deprecated_target_wait_hook(). */
3379 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3381 *ptidp
= target_last_wait_ptid
;
3382 *status
= target_last_waitstatus
;
3386 nullify_last_target_wait_ptid (void)
3388 target_last_wait_ptid
= minus_one_ptid
;
3391 /* Switch thread contexts. */
3394 context_switch (ptid_t ptid
)
3396 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
3398 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3399 target_pid_to_str (inferior_ptid
));
3400 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3401 target_pid_to_str (ptid
));
3404 switch_to_thread (ptid
);
3408 adjust_pc_after_break (struct execution_control_state
*ecs
)
3410 struct regcache
*regcache
;
3411 struct gdbarch
*gdbarch
;
3412 struct address_space
*aspace
;
3413 CORE_ADDR breakpoint_pc
, decr_pc
;
3415 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3416 we aren't, just return.
3418 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3419 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3420 implemented by software breakpoints should be handled through the normal
3423 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3424 different signals (SIGILL or SIGEMT for instance), but it is less
3425 clear where the PC is pointing afterwards. It may not match
3426 gdbarch_decr_pc_after_break. I don't know any specific target that
3427 generates these signals at breakpoints (the code has been in GDB since at
3428 least 1992) so I can not guess how to handle them here.
3430 In earlier versions of GDB, a target with
3431 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3432 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3433 target with both of these set in GDB history, and it seems unlikely to be
3434 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3436 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
3439 if (ecs
->ws
.value
.sig
!= GDB_SIGNAL_TRAP
)
3442 /* In reverse execution, when a breakpoint is hit, the instruction
3443 under it has already been de-executed. The reported PC always
3444 points at the breakpoint address, so adjusting it further would
3445 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3448 B1 0x08000000 : INSN1
3449 B2 0x08000001 : INSN2
3451 PC -> 0x08000003 : INSN4
3453 Say you're stopped at 0x08000003 as above. Reverse continuing
3454 from that point should hit B2 as below. Reading the PC when the
3455 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3456 been de-executed already.
3458 B1 0x08000000 : INSN1
3459 B2 PC -> 0x08000001 : INSN2
3463 We can't apply the same logic as for forward execution, because
3464 we would wrongly adjust the PC to 0x08000000, since there's a
3465 breakpoint at PC - 1. We'd then report a hit on B1, although
3466 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3468 if (execution_direction
== EXEC_REVERSE
)
3471 /* If this target does not decrement the PC after breakpoints, then
3472 we have nothing to do. */
3473 regcache
= get_thread_regcache (ecs
->ptid
);
3474 gdbarch
= get_regcache_arch (regcache
);
3476 decr_pc
= target_decr_pc_after_break (gdbarch
);
3480 aspace
= get_regcache_aspace (regcache
);
3482 /* Find the location where (if we've hit a breakpoint) the
3483 breakpoint would be. */
3484 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3486 /* Check whether there actually is a software breakpoint inserted at
3489 If in non-stop mode, a race condition is possible where we've
3490 removed a breakpoint, but stop events for that breakpoint were
3491 already queued and arrive later. To suppress those spurious
3492 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3493 and retire them after a number of stop events are reported. */
3494 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3495 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3497 struct cleanup
*old_cleanups
= make_cleanup (null_cleanup
, NULL
);
3499 if (record_full_is_used ())
3500 record_full_gdb_operation_disable_set ();
3502 /* When using hardware single-step, a SIGTRAP is reported for both
3503 a completed single-step and a software breakpoint. Need to
3504 differentiate between the two, as the latter needs adjusting
3505 but the former does not.
3507 The SIGTRAP can be due to a completed hardware single-step only if
3508 - we didn't insert software single-step breakpoints
3509 - this thread is currently being stepped
3511 If any of these events did not occur, we must have stopped due
3512 to hitting a software breakpoint, and have to back up to the
3515 As a special case, we could have hardware single-stepped a
3516 software breakpoint. In this case (prev_pc == breakpoint_pc),
3517 we also need to back up to the breakpoint address. */
3519 if (thread_has_single_step_breakpoints_set (ecs
->event_thread
)
3520 || !currently_stepping (ecs
->event_thread
)
3521 || (ecs
->event_thread
->stepped_breakpoint
3522 && ecs
->event_thread
->prev_pc
== breakpoint_pc
))
3523 regcache_write_pc (regcache
, breakpoint_pc
);
3525 do_cleanups (old_cleanups
);
3530 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
3532 for (frame
= get_prev_frame (frame
);
3534 frame
= get_prev_frame (frame
))
3536 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
3538 if (get_frame_type (frame
) != INLINE_FRAME
)
3545 /* Auxiliary function that handles syscall entry/return events.
3546 It returns 1 if the inferior should keep going (and GDB
3547 should ignore the event), or 0 if the event deserves to be
3551 handle_syscall_event (struct execution_control_state
*ecs
)
3553 struct regcache
*regcache
;
3556 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3557 context_switch (ecs
->ptid
);
3559 regcache
= get_thread_regcache (ecs
->ptid
);
3560 syscall_number
= ecs
->ws
.value
.syscall_number
;
3561 stop_pc
= regcache_read_pc (regcache
);
3563 if (catch_syscall_enabled () > 0
3564 && catching_syscall_number (syscall_number
) > 0)
3567 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3570 ecs
->event_thread
->control
.stop_bpstat
3571 = bpstat_stop_status (get_regcache_aspace (regcache
),
3572 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3574 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3576 /* Catchpoint hit. */
3581 /* If no catchpoint triggered for this, then keep going. */
3586 /* Lazily fill in the execution_control_state's stop_func_* fields. */
3589 fill_in_stop_func (struct gdbarch
*gdbarch
,
3590 struct execution_control_state
*ecs
)
3592 if (!ecs
->stop_func_filled_in
)
3594 /* Don't care about return value; stop_func_start and stop_func_name
3595 will both be 0 if it doesn't work. */
3596 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3597 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3598 ecs
->stop_func_start
3599 += gdbarch_deprecated_function_start_offset (gdbarch
);
3601 if (gdbarch_skip_entrypoint_p (gdbarch
))
3602 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
3603 ecs
->stop_func_start
);
3605 ecs
->stop_func_filled_in
= 1;
3610 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
3612 static enum stop_kind
3613 get_inferior_stop_soon (ptid_t ptid
)
3615 struct inferior
*inf
= find_inferior_ptid (ptid
);
3617 gdb_assert (inf
!= NULL
);
3618 return inf
->control
.stop_soon
;
3621 /* Given an execution control state that has been freshly filled in by
3622 an event from the inferior, figure out what it means and take
3625 The alternatives are:
3627 1) stop_waiting and return; to really stop and return to the
3630 2) keep_going and return; to wait for the next event (set
3631 ecs->event_thread->stepping_over_breakpoint to 1 to single step
3635 handle_inferior_event (struct execution_control_state
*ecs
)
3637 enum stop_kind stop_soon
;
3639 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3641 /* We had an event in the inferior, but we are not interested in
3642 handling it at this level. The lower layers have already
3643 done what needs to be done, if anything.
3645 One of the possible circumstances for this is when the
3646 inferior produces output for the console. The inferior has
3647 not stopped, and we are ignoring the event. Another possible
3648 circumstance is any event which the lower level knows will be
3649 reported multiple times without an intervening resume. */
3651 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3652 prepare_to_wait (ecs
);
3656 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
3657 && target_can_async_p () && !sync_execution
)
3659 /* There were no unwaited-for children left in the target, but,
3660 we're not synchronously waiting for events either. Just
3661 ignore. Otherwise, if we were running a synchronous
3662 execution command, we need to cancel it and give the user
3663 back the terminal. */
3665 fprintf_unfiltered (gdb_stdlog
,
3666 "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
3667 prepare_to_wait (ecs
);
3671 /* Cache the last pid/waitstatus. */
3672 set_last_target_status (ecs
->ptid
, ecs
->ws
);
3674 /* Always clear state belonging to the previous time we stopped. */
3675 stop_stack_dummy
= STOP_NONE
;
3677 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
3679 /* No unwaited-for children left. IOW, all resumed children
3682 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
3684 stop_print_frame
= 0;
3689 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3690 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3692 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3693 /* If it's a new thread, add it to the thread database. */
3694 if (ecs
->event_thread
== NULL
)
3695 ecs
->event_thread
= add_thread (ecs
->ptid
);
3697 /* Disable range stepping. If the next step request could use a
3698 range, this will be end up re-enabled then. */
3699 ecs
->event_thread
->control
.may_range_step
= 0;
3702 /* Dependent on valid ECS->EVENT_THREAD. */
3703 adjust_pc_after_break (ecs
);
3705 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3706 reinit_frame_cache ();
3708 breakpoint_retire_moribund ();
3710 /* First, distinguish signals caused by the debugger from signals
3711 that have to do with the program's own actions. Note that
3712 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3713 on the operating system version. Here we detect when a SIGILL or
3714 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3715 something similar for SIGSEGV, since a SIGSEGV will be generated
3716 when we're trying to execute a breakpoint instruction on a
3717 non-executable stack. This happens for call dummy breakpoints
3718 for architectures like SPARC that place call dummies on the
3720 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3721 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
3722 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
3723 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
3725 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3727 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3728 regcache_read_pc (regcache
)))
3731 fprintf_unfiltered (gdb_stdlog
,
3732 "infrun: Treating signal as SIGTRAP\n");
3733 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
3737 /* Mark the non-executing threads accordingly. In all-stop, all
3738 threads of all processes are stopped when we get any event
3739 reported. In non-stop mode, only the event thread stops. If
3740 we're handling a process exit in non-stop mode, there's nothing
3741 to do, as threads of the dead process are gone, and threads of
3742 any other process were left running. */
3744 set_executing (minus_one_ptid
, 0);
3745 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3746 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3747 set_executing (ecs
->ptid
, 0);
3749 switch (ecs
->ws
.kind
)
3751 case TARGET_WAITKIND_LOADED
:
3753 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3754 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3755 context_switch (ecs
->ptid
);
3756 /* Ignore gracefully during startup of the inferior, as it might
3757 be the shell which has just loaded some objects, otherwise
3758 add the symbols for the newly loaded objects. Also ignore at
3759 the beginning of an attach or remote session; we will query
3760 the full list of libraries once the connection is
3763 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
3764 if (stop_soon
== NO_STOP_QUIETLY
)
3766 struct regcache
*regcache
;
3768 regcache
= get_thread_regcache (ecs
->ptid
);
3770 handle_solib_event ();
3772 ecs
->event_thread
->control
.stop_bpstat
3773 = bpstat_stop_status (get_regcache_aspace (regcache
),
3774 stop_pc
, ecs
->ptid
, &ecs
->ws
);
3776 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
3778 /* A catchpoint triggered. */
3779 process_event_stop_test (ecs
);
3783 /* If requested, stop when the dynamic linker notifies
3784 gdb of events. This allows the user to get control
3785 and place breakpoints in initializer routines for
3786 dynamically loaded objects (among other things). */
3787 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
3788 if (stop_on_solib_events
)
3790 /* Make sure we print "Stopped due to solib-event" in
3792 stop_print_frame
= 1;
3799 /* If we are skipping through a shell, or through shared library
3800 loading that we aren't interested in, resume the program. If
3801 we're running the program normally, also resume. */
3802 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3804 /* Loading of shared libraries might have changed breakpoint
3805 addresses. Make sure new breakpoints are inserted. */
3806 if (stop_soon
== NO_STOP_QUIETLY
)
3807 insert_breakpoints ();
3808 resume (0, GDB_SIGNAL_0
);
3809 prepare_to_wait (ecs
);
3813 /* But stop if we're attaching or setting up a remote
3815 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3816 || stop_soon
== STOP_QUIETLY_REMOTE
)
3819 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3824 internal_error (__FILE__
, __LINE__
,
3825 _("unhandled stop_soon: %d"), (int) stop_soon
);
3827 case TARGET_WAITKIND_SPURIOUS
:
3829 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3830 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3831 context_switch (ecs
->ptid
);
3832 resume (0, GDB_SIGNAL_0
);
3833 prepare_to_wait (ecs
);
3836 case TARGET_WAITKIND_EXITED
:
3837 case TARGET_WAITKIND_SIGNALLED
:
3840 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3841 fprintf_unfiltered (gdb_stdlog
,
3842 "infrun: TARGET_WAITKIND_EXITED\n");
3844 fprintf_unfiltered (gdb_stdlog
,
3845 "infrun: TARGET_WAITKIND_SIGNALLED\n");
3848 inferior_ptid
= ecs
->ptid
;
3849 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
3850 set_current_program_space (current_inferior ()->pspace
);
3851 handle_vfork_child_exec_or_exit (0);
3852 target_terminal_ours (); /* Must do this before mourn anyway. */
3854 /* Clearing any previous state of convenience variables. */
3855 clear_exit_convenience_vars ();
3857 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
3859 /* Record the exit code in the convenience variable $_exitcode, so
3860 that the user can inspect this again later. */
3861 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3862 (LONGEST
) ecs
->ws
.value
.integer
);
3864 /* Also record this in the inferior itself. */
3865 current_inferior ()->has_exit_code
= 1;
3866 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
3868 /* Support the --return-child-result option. */
3869 return_child_result_value
= ecs
->ws
.value
.integer
;
3871 observer_notify_exited (ecs
->ws
.value
.integer
);
3875 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3876 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3878 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
3880 /* Set the value of the internal variable $_exitsignal,
3881 which holds the signal uncaught by the inferior. */
3882 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
3883 gdbarch_gdb_signal_to_target (gdbarch
,
3884 ecs
->ws
.value
.sig
));
3888 /* We don't have access to the target's method used for
3889 converting between signal numbers (GDB's internal
3890 representation <-> target's representation).
3891 Therefore, we cannot do a good job at displaying this
3892 information to the user. It's better to just warn
3893 her about it (if infrun debugging is enabled), and
3896 fprintf_filtered (gdb_stdlog
, _("\
3897 Cannot fill $_exitsignal with the correct signal number.\n"));
3900 observer_notify_signal_exited (ecs
->ws
.value
.sig
);
3903 gdb_flush (gdb_stdout
);
3904 target_mourn_inferior ();
3905 stop_print_frame
= 0;
3909 /* The following are the only cases in which we keep going;
3910 the above cases end in a continue or goto. */
3911 case TARGET_WAITKIND_FORKED
:
3912 case TARGET_WAITKIND_VFORKED
:
3915 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3916 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3918 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
3921 /* Check whether the inferior is displaced stepping. */
3923 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3924 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3925 struct displaced_step_inferior_state
*displaced
3926 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
3928 /* If checking displaced stepping is supported, and thread
3929 ecs->ptid is displaced stepping. */
3930 if (displaced
&& ptid_equal (displaced
->step_ptid
, ecs
->ptid
))
3932 struct inferior
*parent_inf
3933 = find_inferior_ptid (ecs
->ptid
);
3934 struct regcache
*child_regcache
;
3935 CORE_ADDR parent_pc
;
3937 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
3938 indicating that the displaced stepping of syscall instruction
3939 has been done. Perform cleanup for parent process here. Note
3940 that this operation also cleans up the child process for vfork,
3941 because their pages are shared. */
3942 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
3944 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
3946 /* Restore scratch pad for child process. */
3947 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
3950 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
3951 the child's PC is also within the scratchpad. Set the child's PC
3952 to the parent's PC value, which has already been fixed up.
3953 FIXME: we use the parent's aspace here, although we're touching
3954 the child, because the child hasn't been added to the inferior
3955 list yet at this point. */
3958 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
3960 parent_inf
->aspace
);
3961 /* Read PC value of parent process. */
3962 parent_pc
= regcache_read_pc (regcache
);
3964 if (debug_displaced
)
3965 fprintf_unfiltered (gdb_stdlog
,
3966 "displaced: write child pc from %s to %s\n",
3968 regcache_read_pc (child_regcache
)),
3969 paddress (gdbarch
, parent_pc
));
3971 regcache_write_pc (child_regcache
, parent_pc
);
3975 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3976 context_switch (ecs
->ptid
);
3978 /* Immediately detach breakpoints from the child before there's
3979 any chance of letting the user delete breakpoints from the
3980 breakpoint lists. If we don't do this early, it's easy to
3981 leave left over traps in the child, vis: "break foo; catch
3982 fork; c; <fork>; del; c; <child calls foo>". We only follow
3983 the fork on the last `continue', and by that time the
3984 breakpoint at "foo" is long gone from the breakpoint table.
3985 If we vforked, then we don't need to unpatch here, since both
3986 parent and child are sharing the same memory pages; we'll
3987 need to unpatch at follow/detach time instead to be certain
3988 that new breakpoints added between catchpoint hit time and
3989 vfork follow are detached. */
3990 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3992 /* This won't actually modify the breakpoint list, but will
3993 physically remove the breakpoints from the child. */
3994 detach_breakpoints (ecs
->ws
.value
.related_pid
);
3997 delete_just_stopped_threads_single_step_breakpoints ();
3999 /* In case the event is caught by a catchpoint, remember that
4000 the event is to be followed at the next resume of the thread,
4001 and not immediately. */
4002 ecs
->event_thread
->pending_follow
= ecs
->ws
;
4004 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4006 ecs
->event_thread
->control
.stop_bpstat
4007 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4008 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4010 /* If no catchpoint triggered for this, then keep going. Note
4011 that we're interested in knowing the bpstat actually causes a
4012 stop, not just if it may explain the signal. Software
4013 watchpoints, for example, always appear in the bpstat. */
4014 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4020 = (follow_fork_mode_string
== follow_fork_mode_child
);
4022 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4024 should_resume
= follow_fork ();
4027 child
= ecs
->ws
.value
.related_pid
;
4029 /* In non-stop mode, also resume the other branch. */
4030 if (non_stop
&& !detach_fork
)
4033 switch_to_thread (parent
);
4035 switch_to_thread (child
);
4037 ecs
->event_thread
= inferior_thread ();
4038 ecs
->ptid
= inferior_ptid
;
4043 switch_to_thread (child
);
4045 switch_to_thread (parent
);
4047 ecs
->event_thread
= inferior_thread ();
4048 ecs
->ptid
= inferior_ptid
;
4056 process_event_stop_test (ecs
);
4059 case TARGET_WAITKIND_VFORK_DONE
:
4060 /* Done with the shared memory region. Re-insert breakpoints in
4061 the parent, and keep going. */
4064 fprintf_unfiltered (gdb_stdlog
,
4065 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
4067 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4068 context_switch (ecs
->ptid
);
4070 current_inferior ()->waiting_for_vfork_done
= 0;
4071 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
4072 /* This also takes care of reinserting breakpoints in the
4073 previously locked inferior. */
4077 case TARGET_WAITKIND_EXECD
:
4079 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
4081 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4082 context_switch (ecs
->ptid
);
4084 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4086 /* Do whatever is necessary to the parent branch of the vfork. */
4087 handle_vfork_child_exec_or_exit (1);
4089 /* This causes the eventpoints and symbol table to be reset.
4090 Must do this now, before trying to determine whether to
4092 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
4094 ecs
->event_thread
->control
.stop_bpstat
4095 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4096 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4098 /* Note that this may be referenced from inside
4099 bpstat_stop_status above, through inferior_has_execd. */
4100 xfree (ecs
->ws
.value
.execd_pathname
);
4101 ecs
->ws
.value
.execd_pathname
= NULL
;
4103 /* If no catchpoint triggered for this, then keep going. */
4104 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4106 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4110 process_event_stop_test (ecs
);
4113 /* Be careful not to try to gather much state about a thread
4114 that's in a syscall. It's frequently a losing proposition. */
4115 case TARGET_WAITKIND_SYSCALL_ENTRY
:
4117 fprintf_unfiltered (gdb_stdlog
,
4118 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
4119 /* Getting the current syscall number. */
4120 if (handle_syscall_event (ecs
) == 0)
4121 process_event_stop_test (ecs
);
4124 /* Before examining the threads further, step this thread to
4125 get it entirely out of the syscall. (We get notice of the
4126 event when the thread is just on the verge of exiting a
4127 syscall. Stepping one instruction seems to get it back
4129 case TARGET_WAITKIND_SYSCALL_RETURN
:
4131 fprintf_unfiltered (gdb_stdlog
,
4132 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
4133 if (handle_syscall_event (ecs
) == 0)
4134 process_event_stop_test (ecs
);
4137 case TARGET_WAITKIND_STOPPED
:
4139 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
4140 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
4141 handle_signal_stop (ecs
);
4144 case TARGET_WAITKIND_NO_HISTORY
:
4146 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
4147 /* Reverse execution: target ran out of history info. */
4149 delete_just_stopped_threads_single_step_breakpoints ();
4150 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4151 observer_notify_no_history ();
4157 /* Come here when the program has stopped with a signal. */
4160 handle_signal_stop (struct execution_control_state
*ecs
)
4162 struct frame_info
*frame
;
4163 struct gdbarch
*gdbarch
;
4164 int stopped_by_watchpoint
;
4165 enum stop_kind stop_soon
;
4168 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
4170 /* Do we need to clean up the state of a thread that has
4171 completed a displaced single-step? (Doing so usually affects
4172 the PC, so do it here, before we set stop_pc.) */
4173 displaced_step_fixup (ecs
->ptid
,
4174 ecs
->event_thread
->suspend
.stop_signal
);
4176 /* If we either finished a single-step or hit a breakpoint, but
4177 the user wanted this thread to be stopped, pretend we got a
4178 SIG0 (generic unsignaled stop). */
4179 if (ecs
->event_thread
->stop_requested
4180 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4181 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4183 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4187 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4188 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
4189 struct cleanup
*old_chain
= save_inferior_ptid ();
4191 inferior_ptid
= ecs
->ptid
;
4193 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
4194 paddress (gdbarch
, stop_pc
));
4195 if (target_stopped_by_watchpoint ())
4199 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
4201 if (target_stopped_data_address (¤t_target
, &addr
))
4202 fprintf_unfiltered (gdb_stdlog
,
4203 "infrun: stopped data address = %s\n",
4204 paddress (gdbarch
, addr
));
4206 fprintf_unfiltered (gdb_stdlog
,
4207 "infrun: (no data address available)\n");
4210 do_cleanups (old_chain
);
4213 /* This is originated from start_remote(), start_inferior() and
4214 shared libraries hook functions. */
4215 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4216 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
4218 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4219 context_switch (ecs
->ptid
);
4221 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4222 stop_print_frame
= 1;
4227 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4230 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4231 context_switch (ecs
->ptid
);
4233 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
4234 stop_print_frame
= 0;
4239 /* This originates from attach_command(). We need to overwrite
4240 the stop_signal here, because some kernels don't ignore a
4241 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
4242 See more comments in inferior.h. On the other hand, if we
4243 get a non-SIGSTOP, report it to the user - assume the backend
4244 will handle the SIGSTOP if it should show up later.
4246 Also consider that the attach is complete when we see a
4247 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
4248 target extended-remote report it instead of a SIGSTOP
4249 (e.g. gdbserver). We already rely on SIGTRAP being our
4250 signal, so this is no exception.
4252 Also consider that the attach is complete when we see a
4253 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
4254 the target to stop all threads of the inferior, in case the
4255 low level attach operation doesn't stop them implicitly. If
4256 they weren't stopped implicitly, then the stub will report a
4257 GDB_SIGNAL_0, meaning: stopped for no particular reason
4258 other than GDB's request. */
4259 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4260 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
4261 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4262 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
4264 stop_print_frame
= 1;
4266 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4270 /* See if something interesting happened to the non-current thread. If
4271 so, then switch to that thread. */
4272 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4275 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
4277 context_switch (ecs
->ptid
);
4279 if (deprecated_context_hook
)
4280 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
4283 /* At this point, get hold of the now-current thread's frame. */
4284 frame
= get_current_frame ();
4285 gdbarch
= get_frame_arch (frame
);
4287 /* Pull the single step breakpoints out of the target. */
4288 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
4290 struct regcache
*regcache
;
4291 struct address_space
*aspace
;
4294 regcache
= get_thread_regcache (ecs
->ptid
);
4295 aspace
= get_regcache_aspace (regcache
);
4296 pc
= regcache_read_pc (regcache
);
4298 /* However, before doing so, if this single-step breakpoint was
4299 actually for another thread, set this thread up for moving
4301 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
4304 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
4308 fprintf_unfiltered (gdb_stdlog
,
4309 "infrun: [%s] hit another thread's "
4310 "single-step breakpoint\n",
4311 target_pid_to_str (ecs
->ptid
));
4313 ecs
->hit_singlestep_breakpoint
= 1;
4320 fprintf_unfiltered (gdb_stdlog
,
4321 "infrun: [%s] hit its "
4322 "single-step breakpoint\n",
4323 target_pid_to_str (ecs
->ptid
));
4327 delete_just_stopped_threads_single_step_breakpoints ();
4329 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4330 && ecs
->event_thread
->control
.trap_expected
4331 && ecs
->event_thread
->stepping_over_watchpoint
)
4332 stopped_by_watchpoint
= 0;
4334 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
4336 /* If necessary, step over this watchpoint. We'll be back to display
4338 if (stopped_by_watchpoint
4339 && (target_have_steppable_watchpoint
4340 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
4342 /* At this point, we are stopped at an instruction which has
4343 attempted to write to a piece of memory under control of
4344 a watchpoint. The instruction hasn't actually executed
4345 yet. If we were to evaluate the watchpoint expression
4346 now, we would get the old value, and therefore no change
4347 would seem to have occurred.
4349 In order to make watchpoints work `right', we really need
4350 to complete the memory write, and then evaluate the
4351 watchpoint expression. We do this by single-stepping the
4354 It may not be necessary to disable the watchpoint to step over
4355 it. For example, the PA can (with some kernel cooperation)
4356 single step over a watchpoint without disabling the watchpoint.
4358 It is far more common to need to disable a watchpoint to step
4359 the inferior over it. If we have non-steppable watchpoints,
4360 we must disable the current watchpoint; it's simplest to
4361 disable all watchpoints.
4363 Any breakpoint at PC must also be stepped over -- if there's
4364 one, it will have already triggered before the watchpoint
4365 triggered, and we either already reported it to the user, or
4366 it didn't cause a stop and we called keep_going. In either
4367 case, if there was a breakpoint at PC, we must be trying to
4369 ecs
->event_thread
->stepping_over_watchpoint
= 1;
4374 ecs
->event_thread
->stepping_over_breakpoint
= 0;
4375 ecs
->event_thread
->stepping_over_watchpoint
= 0;
4376 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4377 ecs
->event_thread
->control
.stop_step
= 0;
4378 stop_print_frame
= 1;
4379 stopped_by_random_signal
= 0;
4381 /* Hide inlined functions starting here, unless we just performed stepi or
4382 nexti. After stepi and nexti, always show the innermost frame (not any
4383 inline function call sites). */
4384 if (ecs
->event_thread
->control
.step_range_end
!= 1)
4386 struct address_space
*aspace
=
4387 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
4389 /* skip_inline_frames is expensive, so we avoid it if we can
4390 determine that the address is one where functions cannot have
4391 been inlined. This improves performance with inferiors that
4392 load a lot of shared libraries, because the solib event
4393 breakpoint is defined as the address of a function (i.e. not
4394 inline). Note that we have to check the previous PC as well
4395 as the current one to catch cases when we have just
4396 single-stepped off a breakpoint prior to reinstating it.
4397 Note that we're assuming that the code we single-step to is
4398 not inline, but that's not definitive: there's nothing
4399 preventing the event breakpoint function from containing
4400 inlined code, and the single-step ending up there. If the
4401 user had set a breakpoint on that inlined code, the missing
4402 skip_inline_frames call would break things. Fortunately
4403 that's an extremely unlikely scenario. */
4404 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
4405 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4406 && ecs
->event_thread
->control
.trap_expected
4407 && pc_at_non_inline_function (aspace
,
4408 ecs
->event_thread
->prev_pc
,
4411 skip_inline_frames (ecs
->ptid
);
4413 /* Re-fetch current thread's frame in case that invalidated
4415 frame
= get_current_frame ();
4416 gdbarch
= get_frame_arch (frame
);
4420 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4421 && ecs
->event_thread
->control
.trap_expected
4422 && gdbarch_single_step_through_delay_p (gdbarch
)
4423 && currently_stepping (ecs
->event_thread
))
4425 /* We're trying to step off a breakpoint. Turns out that we're
4426 also on an instruction that needs to be stepped multiple
4427 times before it's been fully executing. E.g., architectures
4428 with a delay slot. It needs to be stepped twice, once for
4429 the instruction and once for the delay slot. */
4430 int step_through_delay
4431 = gdbarch_single_step_through_delay (gdbarch
, frame
);
4433 if (debug_infrun
&& step_through_delay
)
4434 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
4435 if (ecs
->event_thread
->control
.step_range_end
== 0
4436 && step_through_delay
)
4438 /* The user issued a continue when stopped at a breakpoint.
4439 Set up for another trap and get out of here. */
4440 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4444 else if (step_through_delay
)
4446 /* The user issued a step when stopped at a breakpoint.
4447 Maybe we should stop, maybe we should not - the delay
4448 slot *might* correspond to a line of source. In any
4449 case, don't decide that here, just set
4450 ecs->stepping_over_breakpoint, making sure we
4451 single-step again before breakpoints are re-inserted. */
4452 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4456 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
4457 handles this event. */
4458 ecs
->event_thread
->control
.stop_bpstat
4459 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4460 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4462 /* Following in case break condition called a
4464 stop_print_frame
= 1;
4466 /* This is where we handle "moribund" watchpoints. Unlike
4467 software breakpoints traps, hardware watchpoint traps are
4468 always distinguishable from random traps. If no high-level
4469 watchpoint is associated with the reported stop data address
4470 anymore, then the bpstat does not explain the signal ---
4471 simply make sure to ignore it if `stopped_by_watchpoint' is
4475 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4476 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4478 && stopped_by_watchpoint
)
4479 fprintf_unfiltered (gdb_stdlog
,
4480 "infrun: no user watchpoint explains "
4481 "watchpoint SIGTRAP, ignoring\n");
4483 /* NOTE: cagney/2003-03-29: These checks for a random signal
4484 at one stage in the past included checks for an inferior
4485 function call's call dummy's return breakpoint. The original
4486 comment, that went with the test, read:
4488 ``End of a stack dummy. Some systems (e.g. Sony news) give
4489 another signal besides SIGTRAP, so check here as well as
4492 If someone ever tries to get call dummys on a
4493 non-executable stack to work (where the target would stop
4494 with something like a SIGSEGV), then those tests might need
4495 to be re-instated. Given, however, that the tests were only
4496 enabled when momentary breakpoints were not being used, I
4497 suspect that it won't be the case.
4499 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4500 be necessary for call dummies on a non-executable stack on
4503 /* See if the breakpoints module can explain the signal. */
4505 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
4506 ecs
->event_thread
->suspend
.stop_signal
);
4508 /* If not, perhaps stepping/nexting can. */
4510 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
4511 && currently_stepping (ecs
->event_thread
));
4513 /* Perhaps the thread hit a single-step breakpoint of _another_
4514 thread. Single-step breakpoints are transparent to the
4515 breakpoints module. */
4517 random_signal
= !ecs
->hit_singlestep_breakpoint
;
4519 /* No? Perhaps we got a moribund watchpoint. */
4521 random_signal
= !stopped_by_watchpoint
;
4523 /* For the program's own signals, act according to
4524 the signal handling tables. */
4528 /* Signal not for debugging purposes. */
4529 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
4530 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
4533 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
4534 gdb_signal_to_symbol_string (stop_signal
));
4536 stopped_by_random_signal
= 1;
4538 /* Always stop on signals if we're either just gaining control
4539 of the program, or the user explicitly requested this thread
4540 to remain stopped. */
4541 if (stop_soon
!= NO_STOP_QUIETLY
4542 || ecs
->event_thread
->stop_requested
4544 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4550 /* Notify observers the signal has "handle print" set. Note we
4551 returned early above if stopping; normal_stop handles the
4552 printing in that case. */
4553 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4555 /* The signal table tells us to print about this signal. */
4556 target_terminal_ours_for_output ();
4557 observer_notify_signal_received (ecs
->event_thread
->suspend
.stop_signal
);
4558 target_terminal_inferior ();
4561 /* Clear the signal if it should not be passed. */
4562 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4563 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4565 if (ecs
->event_thread
->prev_pc
== stop_pc
4566 && ecs
->event_thread
->control
.trap_expected
4567 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4569 /* We were just starting a new sequence, attempting to
4570 single-step off of a breakpoint and expecting a SIGTRAP.
4571 Instead this signal arrives. This signal will take us out
4572 of the stepping range so GDB needs to remember to, when
4573 the signal handler returns, resume stepping off that
4575 /* To simplify things, "continue" is forced to use the same
4576 code paths as single-step - set a breakpoint at the
4577 signal return address and then, once hit, step off that
4580 fprintf_unfiltered (gdb_stdlog
,
4581 "infrun: signal arrived while stepping over "
4584 insert_hp_step_resume_breakpoint_at_frame (frame
);
4585 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4586 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4587 ecs
->event_thread
->control
.trap_expected
= 0;
4589 /* If we were nexting/stepping some other thread, switch to
4590 it, so that we don't continue it, losing control. */
4591 if (!switch_back_to_stepped_thread (ecs
))
4596 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
4597 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4598 || ecs
->event_thread
->control
.step_range_end
== 1)
4599 && frame_id_eq (get_stack_frame_id (frame
),
4600 ecs
->event_thread
->control
.step_stack_frame_id
)
4601 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4603 /* The inferior is about to take a signal that will take it
4604 out of the single step range. Set a breakpoint at the
4605 current PC (which is presumably where the signal handler
4606 will eventually return) and then allow the inferior to
4609 Note that this is only needed for a signal delivered
4610 while in the single-step range. Nested signals aren't a
4611 problem as they eventually all return. */
4613 fprintf_unfiltered (gdb_stdlog
,
4614 "infrun: signal may take us out of "
4615 "single-step range\n");
4617 insert_hp_step_resume_breakpoint_at_frame (frame
);
4618 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4619 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4620 ecs
->event_thread
->control
.trap_expected
= 0;
4625 /* Note: step_resume_breakpoint may be non-NULL. This occures
4626 when either there's a nested signal, or when there's a
4627 pending signal enabled just as the signal handler returns
4628 (leaving the inferior at the step-resume-breakpoint without
4629 actually executing it). Either way continue until the
4630 breakpoint is really hit. */
4632 if (!switch_back_to_stepped_thread (ecs
))
4635 fprintf_unfiltered (gdb_stdlog
,
4636 "infrun: random signal, keep going\n");
4643 process_event_stop_test (ecs
);
4646 /* Come here when we've got some debug event / signal we can explain
4647 (IOW, not a random signal), and test whether it should cause a
4648 stop, or whether we should resume the inferior (transparently).
4649 E.g., could be a breakpoint whose condition evaluates false; we
4650 could be still stepping within the line; etc. */
4653 process_event_stop_test (struct execution_control_state
*ecs
)
4655 struct symtab_and_line stop_pc_sal
;
4656 struct frame_info
*frame
;
4657 struct gdbarch
*gdbarch
;
4658 CORE_ADDR jmp_buf_pc
;
4659 struct bpstat_what what
;
4661 /* Handle cases caused by hitting a breakpoint. */
4663 frame
= get_current_frame ();
4664 gdbarch
= get_frame_arch (frame
);
4666 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4668 if (what
.call_dummy
)
4670 stop_stack_dummy
= what
.call_dummy
;
4673 /* If we hit an internal event that triggers symbol changes, the
4674 current frame will be invalidated within bpstat_what (e.g., if we
4675 hit an internal solib event). Re-fetch it. */
4676 frame
= get_current_frame ();
4677 gdbarch
= get_frame_arch (frame
);
4679 switch (what
.main_action
)
4681 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4682 /* If we hit the breakpoint at longjmp while stepping, we
4683 install a momentary breakpoint at the target of the
4687 fprintf_unfiltered (gdb_stdlog
,
4688 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4690 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4692 if (what
.is_longjmp
)
4694 struct value
*arg_value
;
4696 /* If we set the longjmp breakpoint via a SystemTap probe,
4697 then use it to extract the arguments. The destination PC
4698 is the third argument to the probe. */
4699 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
4702 jmp_buf_pc
= value_as_address (arg_value
);
4703 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
4705 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
4706 || !gdbarch_get_longjmp_target (gdbarch
,
4707 frame
, &jmp_buf_pc
))
4710 fprintf_unfiltered (gdb_stdlog
,
4711 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4712 "(!gdbarch_get_longjmp_target)\n");
4717 /* Insert a breakpoint at resume address. */
4718 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4721 check_exception_resume (ecs
, frame
);
4725 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4727 struct frame_info
*init_frame
;
4729 /* There are several cases to consider.
4731 1. The initiating frame no longer exists. In this case we
4732 must stop, because the exception or longjmp has gone too
4735 2. The initiating frame exists, and is the same as the
4736 current frame. We stop, because the exception or longjmp
4739 3. The initiating frame exists and is different from the
4740 current frame. This means the exception or longjmp has
4741 been caught beneath the initiating frame, so keep going.
4743 4. longjmp breakpoint has been placed just to protect
4744 against stale dummy frames and user is not interested in
4745 stopping around longjmps. */
4748 fprintf_unfiltered (gdb_stdlog
,
4749 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4751 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4753 delete_exception_resume_breakpoint (ecs
->event_thread
);
4755 if (what
.is_longjmp
)
4757 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
4759 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
4767 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4771 struct frame_id current_id
4772 = get_frame_id (get_current_frame ());
4773 if (frame_id_eq (current_id
,
4774 ecs
->event_thread
->initiating_frame
))
4776 /* Case 2. Fall through. */
4786 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
4788 delete_step_resume_breakpoint (ecs
->event_thread
);
4790 end_stepping_range (ecs
);
4794 case BPSTAT_WHAT_SINGLE
:
4796 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4797 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4798 /* Still need to check other stuff, at least the case where we
4799 are stepping and step out of the right range. */
4802 case BPSTAT_WHAT_STEP_RESUME
:
4804 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4806 delete_step_resume_breakpoint (ecs
->event_thread
);
4807 if (ecs
->event_thread
->control
.proceed_to_finish
4808 && execution_direction
== EXEC_REVERSE
)
4810 struct thread_info
*tp
= ecs
->event_thread
;
4812 /* We are finishing a function in reverse, and just hit the
4813 step-resume breakpoint at the start address of the
4814 function, and we're almost there -- just need to back up
4815 by one more single-step, which should take us back to the
4817 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
4821 fill_in_stop_func (gdbarch
, ecs
);
4822 if (stop_pc
== ecs
->stop_func_start
4823 && execution_direction
== EXEC_REVERSE
)
4825 /* We are stepping over a function call in reverse, and just
4826 hit the step-resume breakpoint at the start address of
4827 the function. Go back to single-stepping, which should
4828 take us back to the function call. */
4829 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4835 case BPSTAT_WHAT_STOP_NOISY
:
4837 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4838 stop_print_frame
= 1;
4840 /* Assume the thread stopped for a breapoint. We'll still check
4841 whether a/the breakpoint is there when the thread is next
4843 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4848 case BPSTAT_WHAT_STOP_SILENT
:
4850 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4851 stop_print_frame
= 0;
4853 /* Assume the thread stopped for a breapoint. We'll still check
4854 whether a/the breakpoint is there when the thread is next
4856 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4860 case BPSTAT_WHAT_HP_STEP_RESUME
:
4862 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
4864 delete_step_resume_breakpoint (ecs
->event_thread
);
4865 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4867 /* Back when the step-resume breakpoint was inserted, we
4868 were trying to single-step off a breakpoint. Go back to
4870 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4871 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4877 case BPSTAT_WHAT_KEEP_CHECKING
:
4881 /* If we stepped a permanent breakpoint and we had a high priority
4882 step-resume breakpoint for the address we stepped, but we didn't
4883 hit it, then we must have stepped into the signal handler. The
4884 step-resume was only necessary to catch the case of _not_
4885 stepping into the handler, so delete it, and fall through to
4886 checking whether the step finished. */
4887 if (ecs
->event_thread
->stepped_breakpoint
)
4889 struct breakpoint
*sr_bp
4890 = ecs
->event_thread
->control
.step_resume_breakpoint
;
4892 if (sr_bp
->loc
->permanent
4893 && sr_bp
->type
== bp_hp_step_resume
4894 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
4897 fprintf_unfiltered (gdb_stdlog
,
4898 "infrun: stepped permanent breakpoint, stopped in "
4900 delete_step_resume_breakpoint (ecs
->event_thread
);
4901 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4905 /* We come here if we hit a breakpoint but should not stop for it.
4906 Possibly we also were stepping and should stop for that. So fall
4907 through and test for stepping. But, if not stepping, do not
4910 /* In all-stop mode, if we're currently stepping but have stopped in
4911 some other thread, we need to switch back to the stepped thread. */
4912 if (switch_back_to_stepped_thread (ecs
))
4915 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4918 fprintf_unfiltered (gdb_stdlog
,
4919 "infrun: step-resume breakpoint is inserted\n");
4921 /* Having a step-resume breakpoint overrides anything
4922 else having to do with stepping commands until
4923 that breakpoint is reached. */
4928 if (ecs
->event_thread
->control
.step_range_end
== 0)
4931 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4932 /* Likewise if we aren't even stepping. */
4937 /* Re-fetch current thread's frame in case the code above caused
4938 the frame cache to be re-initialized, making our FRAME variable
4939 a dangling pointer. */
4940 frame
= get_current_frame ();
4941 gdbarch
= get_frame_arch (frame
);
4942 fill_in_stop_func (gdbarch
, ecs
);
4944 /* If stepping through a line, keep going if still within it.
4946 Note that step_range_end is the address of the first instruction
4947 beyond the step range, and NOT the address of the last instruction
4950 Note also that during reverse execution, we may be stepping
4951 through a function epilogue and therefore must detect when
4952 the current-frame changes in the middle of a line. */
4954 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
4955 && (execution_direction
!= EXEC_REVERSE
4956 || frame_id_eq (get_frame_id (frame
),
4957 ecs
->event_thread
->control
.step_frame_id
)))
4961 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4962 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4963 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4965 /* Tentatively re-enable range stepping; `resume' disables it if
4966 necessary (e.g., if we're stepping over a breakpoint or we
4967 have software watchpoints). */
4968 ecs
->event_thread
->control
.may_range_step
= 1;
4970 /* When stepping backward, stop at beginning of line range
4971 (unless it's the function entry point, in which case
4972 keep going back to the call point). */
4973 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4974 && stop_pc
!= ecs
->stop_func_start
4975 && execution_direction
== EXEC_REVERSE
)
4976 end_stepping_range (ecs
);
4983 /* We stepped out of the stepping range. */
4985 /* If we are stepping at the source level and entered the runtime
4986 loader dynamic symbol resolution code...
4988 EXEC_FORWARD: we keep on single stepping until we exit the run
4989 time loader code and reach the callee's address.
4991 EXEC_REVERSE: we've already executed the callee (backward), and
4992 the runtime loader code is handled just like any other
4993 undebuggable function call. Now we need only keep stepping
4994 backward through the trampoline code, and that's handled further
4995 down, so there is nothing for us to do here. */
4997 if (execution_direction
!= EXEC_REVERSE
4998 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4999 && in_solib_dynsym_resolve_code (stop_pc
))
5001 CORE_ADDR pc_after_resolver
=
5002 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
5005 fprintf_unfiltered (gdb_stdlog
,
5006 "infrun: stepped into dynsym resolve code\n");
5008 if (pc_after_resolver
)
5010 /* Set up a step-resume breakpoint at the address
5011 indicated by SKIP_SOLIB_RESOLVER. */
5012 struct symtab_and_line sr_sal
;
5015 sr_sal
.pc
= pc_after_resolver
;
5016 sr_sal
.pspace
= get_frame_program_space (frame
);
5018 insert_step_resume_breakpoint_at_sal (gdbarch
,
5019 sr_sal
, null_frame_id
);
5026 if (ecs
->event_thread
->control
.step_range_end
!= 1
5027 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5028 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5029 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
5032 fprintf_unfiltered (gdb_stdlog
,
5033 "infrun: stepped into signal trampoline\n");
5034 /* The inferior, while doing a "step" or "next", has ended up in
5035 a signal trampoline (either by a signal being delivered or by
5036 the signal handler returning). Just single-step until the
5037 inferior leaves the trampoline (either by calling the handler
5043 /* If we're in the return path from a shared library trampoline,
5044 we want to proceed through the trampoline when stepping. */
5045 /* macro/2012-04-25: This needs to come before the subroutine
5046 call check below as on some targets return trampolines look
5047 like subroutine calls (MIPS16 return thunks). */
5048 if (gdbarch_in_solib_return_trampoline (gdbarch
,
5049 stop_pc
, ecs
->stop_func_name
)
5050 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5052 /* Determine where this trampoline returns. */
5053 CORE_ADDR real_stop_pc
;
5055 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5058 fprintf_unfiltered (gdb_stdlog
,
5059 "infrun: stepped into solib return tramp\n");
5061 /* Only proceed through if we know where it's going. */
5064 /* And put the step-breakpoint there and go until there. */
5065 struct symtab_and_line sr_sal
;
5067 init_sal (&sr_sal
); /* initialize to zeroes */
5068 sr_sal
.pc
= real_stop_pc
;
5069 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5070 sr_sal
.pspace
= get_frame_program_space (frame
);
5072 /* Do not specify what the fp should be when we stop since
5073 on some machines the prologue is where the new fp value
5075 insert_step_resume_breakpoint_at_sal (gdbarch
,
5076 sr_sal
, null_frame_id
);
5078 /* Restart without fiddling with the step ranges or
5085 /* Check for subroutine calls. The check for the current frame
5086 equalling the step ID is not necessary - the check of the
5087 previous frame's ID is sufficient - but it is a common case and
5088 cheaper than checking the previous frame's ID.
5090 NOTE: frame_id_eq will never report two invalid frame IDs as
5091 being equal, so to get into this block, both the current and
5092 previous frame must have valid frame IDs. */
5093 /* The outer_frame_id check is a heuristic to detect stepping
5094 through startup code. If we step over an instruction which
5095 sets the stack pointer from an invalid value to a valid value,
5096 we may detect that as a subroutine call from the mythical
5097 "outermost" function. This could be fixed by marking
5098 outermost frames as !stack_p,code_p,special_p. Then the
5099 initial outermost frame, before sp was valid, would
5100 have code_addr == &_start. See the comment in frame_id_eq
5102 if (!frame_id_eq (get_stack_frame_id (frame
),
5103 ecs
->event_thread
->control
.step_stack_frame_id
)
5104 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
5105 ecs
->event_thread
->control
.step_stack_frame_id
)
5106 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
5108 || step_start_function
!= find_pc_function (stop_pc
))))
5110 CORE_ADDR real_stop_pc
;
5113 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
5115 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
5117 /* I presume that step_over_calls is only 0 when we're
5118 supposed to be stepping at the assembly language level
5119 ("stepi"). Just stop. */
5120 /* And this works the same backward as frontward. MVS */
5121 end_stepping_range (ecs
);
5125 /* Reverse stepping through solib trampolines. */
5127 if (execution_direction
== EXEC_REVERSE
5128 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
5129 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5130 || (ecs
->stop_func_start
== 0
5131 && in_solib_dynsym_resolve_code (stop_pc
))))
5133 /* Any solib trampoline code can be handled in reverse
5134 by simply continuing to single-step. We have already
5135 executed the solib function (backwards), and a few
5136 steps will take us back through the trampoline to the
5142 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5144 /* We're doing a "next".
5146 Normal (forward) execution: set a breakpoint at the
5147 callee's return address (the address at which the caller
5150 Reverse (backward) execution. set the step-resume
5151 breakpoint at the start of the function that we just
5152 stepped into (backwards), and continue to there. When we
5153 get there, we'll need to single-step back to the caller. */
5155 if (execution_direction
== EXEC_REVERSE
)
5157 /* If we're already at the start of the function, we've either
5158 just stepped backward into a single instruction function,
5159 or stepped back out of a signal handler to the first instruction
5160 of the function. Just keep going, which will single-step back
5162 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
5164 struct symtab_and_line sr_sal
;
5166 /* Normal function call return (static or dynamic). */
5168 sr_sal
.pc
= ecs
->stop_func_start
;
5169 sr_sal
.pspace
= get_frame_program_space (frame
);
5170 insert_step_resume_breakpoint_at_sal (gdbarch
,
5171 sr_sal
, null_frame_id
);
5175 insert_step_resume_breakpoint_at_caller (frame
);
5181 /* If we are in a function call trampoline (a stub between the
5182 calling routine and the real function), locate the real
5183 function. That's what tells us (a) whether we want to step
5184 into it at all, and (b) what prologue we want to run to the
5185 end of, if we do step into it. */
5186 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
5187 if (real_stop_pc
== 0)
5188 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
5189 if (real_stop_pc
!= 0)
5190 ecs
->stop_func_start
= real_stop_pc
;
5192 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
5194 struct symtab_and_line sr_sal
;
5197 sr_sal
.pc
= ecs
->stop_func_start
;
5198 sr_sal
.pspace
= get_frame_program_space (frame
);
5200 insert_step_resume_breakpoint_at_sal (gdbarch
,
5201 sr_sal
, null_frame_id
);
5206 /* If we have line number information for the function we are
5207 thinking of stepping into and the function isn't on the skip
5210 If there are several symtabs at that PC (e.g. with include
5211 files), just want to know whether *any* of them have line
5212 numbers. find_pc_line handles this. */
5214 struct symtab_and_line tmp_sal
;
5216 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5217 if (tmp_sal
.line
!= 0
5218 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
5221 if (execution_direction
== EXEC_REVERSE
)
5222 handle_step_into_function_backward (gdbarch
, ecs
);
5224 handle_step_into_function (gdbarch
, ecs
);
5229 /* If we have no line number and the step-stop-if-no-debug is
5230 set, we stop the step so that the user has a chance to switch
5231 in assembly mode. */
5232 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5233 && step_stop_if_no_debug
)
5235 end_stepping_range (ecs
);
5239 if (execution_direction
== EXEC_REVERSE
)
5241 /* If we're already at the start of the function, we've either just
5242 stepped backward into a single instruction function without line
5243 number info, or stepped back out of a signal handler to the first
5244 instruction of the function without line number info. Just keep
5245 going, which will single-step back to the caller. */
5246 if (ecs
->stop_func_start
!= stop_pc
)
5248 /* Set a breakpoint at callee's start address.
5249 From there we can step once and be back in the caller. */
5250 struct symtab_and_line sr_sal
;
5253 sr_sal
.pc
= ecs
->stop_func_start
;
5254 sr_sal
.pspace
= get_frame_program_space (frame
);
5255 insert_step_resume_breakpoint_at_sal (gdbarch
,
5256 sr_sal
, null_frame_id
);
5260 /* Set a breakpoint at callee's return address (the address
5261 at which the caller will resume). */
5262 insert_step_resume_breakpoint_at_caller (frame
);
5268 /* Reverse stepping through solib trampolines. */
5270 if (execution_direction
== EXEC_REVERSE
5271 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
5273 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
5274 || (ecs
->stop_func_start
== 0
5275 && in_solib_dynsym_resolve_code (stop_pc
)))
5277 /* Any solib trampoline code can be handled in reverse
5278 by simply continuing to single-step. We have already
5279 executed the solib function (backwards), and a few
5280 steps will take us back through the trampoline to the
5285 else if (in_solib_dynsym_resolve_code (stop_pc
))
5287 /* Stepped backward into the solib dynsym resolver.
5288 Set a breakpoint at its start and continue, then
5289 one more step will take us out. */
5290 struct symtab_and_line sr_sal
;
5293 sr_sal
.pc
= ecs
->stop_func_start
;
5294 sr_sal
.pspace
= get_frame_program_space (frame
);
5295 insert_step_resume_breakpoint_at_sal (gdbarch
,
5296 sr_sal
, null_frame_id
);
5302 stop_pc_sal
= find_pc_line (stop_pc
, 0);
5304 /* NOTE: tausq/2004-05-24: This if block used to be done before all
5305 the trampoline processing logic, however, there are some trampolines
5306 that have no names, so we should do trampoline handling first. */
5307 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
5308 && ecs
->stop_func_name
== NULL
5309 && stop_pc_sal
.line
== 0)
5312 fprintf_unfiltered (gdb_stdlog
,
5313 "infrun: stepped into undebuggable function\n");
5315 /* The inferior just stepped into, or returned to, an
5316 undebuggable function (where there is no debugging information
5317 and no line number corresponding to the address where the
5318 inferior stopped). Since we want to skip this kind of code,
5319 we keep going until the inferior returns from this
5320 function - unless the user has asked us not to (via
5321 set step-mode) or we no longer know how to get back
5322 to the call site. */
5323 if (step_stop_if_no_debug
5324 || !frame_id_p (frame_unwind_caller_id (frame
)))
5326 /* If we have no line number and the step-stop-if-no-debug
5327 is set, we stop the step so that the user has a chance to
5328 switch in assembly mode. */
5329 end_stepping_range (ecs
);
5334 /* Set a breakpoint at callee's return address (the address
5335 at which the caller will resume). */
5336 insert_step_resume_breakpoint_at_caller (frame
);
5342 if (ecs
->event_thread
->control
.step_range_end
== 1)
5344 /* It is stepi or nexti. We always want to stop stepping after
5347 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
5348 end_stepping_range (ecs
);
5352 if (stop_pc_sal
.line
== 0)
5354 /* We have no line number information. That means to stop
5355 stepping (does this always happen right after one instruction,
5356 when we do "s" in a function with no line numbers,
5357 or can this happen as a result of a return or longjmp?). */
5359 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
5360 end_stepping_range (ecs
);
5364 /* Look for "calls" to inlined functions, part one. If the inline
5365 frame machinery detected some skipped call sites, we have entered
5366 a new inline function. */
5368 if (frame_id_eq (get_frame_id (get_current_frame ()),
5369 ecs
->event_thread
->control
.step_frame_id
)
5370 && inline_skipped_frames (ecs
->ptid
))
5372 struct symtab_and_line call_sal
;
5375 fprintf_unfiltered (gdb_stdlog
,
5376 "infrun: stepped into inlined function\n");
5378 find_frame_sal (get_current_frame (), &call_sal
);
5380 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
5382 /* For "step", we're going to stop. But if the call site
5383 for this inlined function is on the same source line as
5384 we were previously stepping, go down into the function
5385 first. Otherwise stop at the call site. */
5387 if (call_sal
.line
== ecs
->event_thread
->current_line
5388 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5389 step_into_inline_frame (ecs
->ptid
);
5391 end_stepping_range (ecs
);
5396 /* For "next", we should stop at the call site if it is on a
5397 different source line. Otherwise continue through the
5398 inlined function. */
5399 if (call_sal
.line
== ecs
->event_thread
->current_line
5400 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
5403 end_stepping_range (ecs
);
5408 /* Look for "calls" to inlined functions, part two. If we are still
5409 in the same real function we were stepping through, but we have
5410 to go further up to find the exact frame ID, we are stepping
5411 through a more inlined call beyond its call site. */
5413 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
5414 && !frame_id_eq (get_frame_id (get_current_frame ()),
5415 ecs
->event_thread
->control
.step_frame_id
)
5416 && stepped_in_from (get_current_frame (),
5417 ecs
->event_thread
->control
.step_frame_id
))
5420 fprintf_unfiltered (gdb_stdlog
,
5421 "infrun: stepping through inlined function\n");
5423 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
5426 end_stepping_range (ecs
);
5430 if ((stop_pc
== stop_pc_sal
.pc
)
5431 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5432 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5434 /* We are at the start of a different line. So stop. Note that
5435 we don't stop if we step into the middle of a different line.
5436 That is said to make things like for (;;) statements work
5439 fprintf_unfiltered (gdb_stdlog
,
5440 "infrun: stepped to a different line\n");
5441 end_stepping_range (ecs
);
5445 /* We aren't done stepping.
5447 Optimize by setting the stepping range to the line.
5448 (We might not be in the original line, but if we entered a
5449 new line in mid-statement, we continue stepping. This makes
5450 things like for(;;) statements work better.) */
5452 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5453 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5454 ecs
->event_thread
->control
.may_range_step
= 1;
5455 set_step_info (frame
, stop_pc_sal
);
5458 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5462 /* In all-stop mode, if we're currently stepping but have stopped in
5463 some other thread, we may need to switch back to the stepped
5464 thread. Returns true we set the inferior running, false if we left
5465 it stopped (and the event needs further processing). */
5468 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
5472 struct thread_info
*tp
;
5473 struct thread_info
*stepping_thread
;
5474 struct thread_info
*step_over
;
5476 /* If any thread is blocked on some internal breakpoint, and we
5477 simply need to step over that breakpoint to get it going
5478 again, do that first. */
5480 /* However, if we see an event for the stepping thread, then we
5481 know all other threads have been moved past their breakpoints
5482 already. Let the caller check whether the step is finished,
5483 etc., before deciding to move it past a breakpoint. */
5484 if (ecs
->event_thread
->control
.step_range_end
!= 0)
5487 /* Check if the current thread is blocked on an incomplete
5488 step-over, interrupted by a random signal. */
5489 if (ecs
->event_thread
->control
.trap_expected
5490 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
5494 fprintf_unfiltered (gdb_stdlog
,
5495 "infrun: need to finish step-over of [%s]\n",
5496 target_pid_to_str (ecs
->event_thread
->ptid
));
5502 /* Check if the current thread is blocked by a single-step
5503 breakpoint of another thread. */
5504 if (ecs
->hit_singlestep_breakpoint
)
5508 fprintf_unfiltered (gdb_stdlog
,
5509 "infrun: need to step [%s] over single-step "
5511 target_pid_to_str (ecs
->ptid
));
5517 /* Otherwise, we no longer expect a trap in the current thread.
5518 Clear the trap_expected flag before switching back -- this is
5519 what keep_going does as well, if we call it. */
5520 ecs
->event_thread
->control
.trap_expected
= 0;
5522 /* Likewise, clear the signal if it should not be passed. */
5523 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5524 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5526 /* If scheduler locking applies even if not stepping, there's no
5527 need to walk over threads. Above we've checked whether the
5528 current thread is stepping. If some other thread not the
5529 event thread is stepping, then it must be that scheduler
5530 locking is not in effect. */
5531 if (schedlock_applies (0))
5534 /* Look for the stepping/nexting thread, and check if any other
5535 thread other than the stepping thread needs to start a
5536 step-over. Do all step-overs before actually proceeding with
5538 stepping_thread
= NULL
;
5540 ALL_NON_EXITED_THREADS (tp
)
5542 /* Ignore threads of processes we're not resuming. */
5544 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (inferior_ptid
))
5547 /* When stepping over a breakpoint, we lock all threads
5548 except the one that needs to move past the breakpoint.
5549 If a non-event thread has this set, the "incomplete
5550 step-over" check above should have caught it earlier. */
5551 gdb_assert (!tp
->control
.trap_expected
);
5553 /* Did we find the stepping thread? */
5554 if (tp
->control
.step_range_end
)
5556 /* Yep. There should only one though. */
5557 gdb_assert (stepping_thread
== NULL
);
5559 /* The event thread is handled at the top, before we
5561 gdb_assert (tp
!= ecs
->event_thread
);
5563 /* If some thread other than the event thread is
5564 stepping, then scheduler locking can't be in effect,
5565 otherwise we wouldn't have resumed the current event
5566 thread in the first place. */
5567 gdb_assert (!schedlock_applies (currently_stepping (tp
)));
5569 stepping_thread
= tp
;
5571 else if (thread_still_needs_step_over (tp
))
5575 /* At the top we've returned early if the event thread
5576 is stepping. If some other thread not the event
5577 thread is stepping, then scheduler locking can't be
5578 in effect, and we can resume this thread. No need to
5579 keep looking for the stepping thread then. */
5584 if (step_over
!= NULL
)
5589 fprintf_unfiltered (gdb_stdlog
,
5590 "infrun: need to step-over [%s]\n",
5591 target_pid_to_str (tp
->ptid
));
5594 /* Only the stepping thread should have this set. */
5595 gdb_assert (tp
->control
.step_range_end
== 0);
5597 ecs
->ptid
= tp
->ptid
;
5598 ecs
->event_thread
= tp
;
5599 switch_to_thread (ecs
->ptid
);
5604 if (stepping_thread
!= NULL
)
5606 struct frame_info
*frame
;
5607 struct gdbarch
*gdbarch
;
5609 tp
= stepping_thread
;
5611 /* If the stepping thread exited, then don't try to switch
5612 back and resume it, which could fail in several different
5613 ways depending on the target. Instead, just keep going.
5615 We can find a stepping dead thread in the thread list in
5618 - The target supports thread exit events, and when the
5619 target tries to delete the thread from the thread list,
5620 inferior_ptid pointed at the exiting thread. In such
5621 case, calling delete_thread does not really remove the
5622 thread from the list; instead, the thread is left listed,
5623 with 'exited' state.
5625 - The target's debug interface does not support thread
5626 exit events, and so we have no idea whatsoever if the
5627 previously stepping thread is still alive. For that
5628 reason, we need to synchronously query the target
5630 if (is_exited (tp
->ptid
)
5631 || !target_thread_alive (tp
->ptid
))
5634 fprintf_unfiltered (gdb_stdlog
,
5635 "infrun: not switching back to "
5636 "stepped thread, it has vanished\n");
5638 delete_thread (tp
->ptid
);
5644 fprintf_unfiltered (gdb_stdlog
,
5645 "infrun: switching back to stepped thread\n");
5647 ecs
->event_thread
= tp
;
5648 ecs
->ptid
= tp
->ptid
;
5649 context_switch (ecs
->ptid
);
5651 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5652 frame
= get_current_frame ();
5653 gdbarch
= get_frame_arch (frame
);
5655 /* If the PC of the thread we were trying to single-step has
5656 changed, then that thread has trapped or been signaled,
5657 but the event has not been reported to GDB yet. Re-poll
5658 the target looking for this particular thread's event
5659 (i.e. temporarily enable schedlock) by:
5661 - setting a break at the current PC
5662 - resuming that particular thread, only (by setting
5665 This prevents us continuously moving the single-step
5666 breakpoint forward, one instruction at a time,
5669 if (stop_pc
!= tp
->prev_pc
)
5672 fprintf_unfiltered (gdb_stdlog
,
5673 "infrun: expected thread advanced also\n");
5675 /* Clear the info of the previous step-over, as it's no
5676 longer valid. It's what keep_going would do too, if
5677 we called it. Must do this before trying to insert
5678 the sss breakpoint, otherwise if we were previously
5679 trying to step over this exact address in another
5680 thread, the breakpoint ends up not installed. */
5681 clear_step_over_info ();
5683 insert_single_step_breakpoint (get_frame_arch (frame
),
5684 get_frame_address_space (frame
),
5686 ecs
->event_thread
->control
.trap_expected
= 1;
5688 resume (0, GDB_SIGNAL_0
);
5689 prepare_to_wait (ecs
);
5694 fprintf_unfiltered (gdb_stdlog
,
5695 "infrun: expected thread still "
5696 "hasn't advanced\n");
5706 /* Is thread TP in the middle of single-stepping? */
5709 currently_stepping (struct thread_info
*tp
)
5711 return ((tp
->control
.step_range_end
5712 && tp
->control
.step_resume_breakpoint
== NULL
)
5713 || tp
->control
.trap_expected
5714 || tp
->stepped_breakpoint
5715 || bpstat_should_step ());
5718 /* Inferior has stepped into a subroutine call with source code that
5719 we should not step over. Do step to the first line of code in
5723 handle_step_into_function (struct gdbarch
*gdbarch
,
5724 struct execution_control_state
*ecs
)
5726 struct compunit_symtab
*cust
;
5727 struct symtab_and_line stop_func_sal
, sr_sal
;
5729 fill_in_stop_func (gdbarch
, ecs
);
5731 cust
= find_pc_compunit_symtab (stop_pc
);
5732 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
5733 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5734 ecs
->stop_func_start
);
5736 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5737 /* Use the step_resume_break to step until the end of the prologue,
5738 even if that involves jumps (as it seems to on the vax under
5740 /* If the prologue ends in the middle of a source line, continue to
5741 the end of that source line (if it is still within the function).
5742 Otherwise, just go to end of prologue. */
5743 if (stop_func_sal
.end
5744 && stop_func_sal
.pc
!= ecs
->stop_func_start
5745 && stop_func_sal
.end
< ecs
->stop_func_end
)
5746 ecs
->stop_func_start
= stop_func_sal
.end
;
5748 /* Architectures which require breakpoint adjustment might not be able
5749 to place a breakpoint at the computed address. If so, the test
5750 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5751 ecs->stop_func_start to an address at which a breakpoint may be
5752 legitimately placed.
5754 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5755 made, GDB will enter an infinite loop when stepping through
5756 optimized code consisting of VLIW instructions which contain
5757 subinstructions corresponding to different source lines. On
5758 FR-V, it's not permitted to place a breakpoint on any but the
5759 first subinstruction of a VLIW instruction. When a breakpoint is
5760 set, GDB will adjust the breakpoint address to the beginning of
5761 the VLIW instruction. Thus, we need to make the corresponding
5762 adjustment here when computing the stop address. */
5764 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5766 ecs
->stop_func_start
5767 = gdbarch_adjust_breakpoint_address (gdbarch
,
5768 ecs
->stop_func_start
);
5771 if (ecs
->stop_func_start
== stop_pc
)
5773 /* We are already there: stop now. */
5774 end_stepping_range (ecs
);
5779 /* Put the step-breakpoint there and go until there. */
5780 init_sal (&sr_sal
); /* initialize to zeroes */
5781 sr_sal
.pc
= ecs
->stop_func_start
;
5782 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5783 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5785 /* Do not specify what the fp should be when we stop since on
5786 some machines the prologue is where the new fp value is
5788 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5790 /* And make sure stepping stops right away then. */
5791 ecs
->event_thread
->control
.step_range_end
5792 = ecs
->event_thread
->control
.step_range_start
;
5797 /* Inferior has stepped backward into a subroutine call with source
5798 code that we should not step over. Do step to the beginning of the
5799 last line of code in it. */
5802 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5803 struct execution_control_state
*ecs
)
5805 struct compunit_symtab
*cust
;
5806 struct symtab_and_line stop_func_sal
;
5808 fill_in_stop_func (gdbarch
, ecs
);
5810 cust
= find_pc_compunit_symtab (stop_pc
);
5811 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
5812 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5813 ecs
->stop_func_start
);
5815 stop_func_sal
= find_pc_line (stop_pc
, 0);
5817 /* OK, we're just going to keep stepping here. */
5818 if (stop_func_sal
.pc
== stop_pc
)
5820 /* We're there already. Just stop stepping now. */
5821 end_stepping_range (ecs
);
5825 /* Else just reset the step range and keep going.
5826 No step-resume breakpoint, they don't work for
5827 epilogues, which can have multiple entry paths. */
5828 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5829 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5835 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5836 This is used to both functions and to skip over code. */
5839 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
5840 struct symtab_and_line sr_sal
,
5841 struct frame_id sr_id
,
5842 enum bptype sr_type
)
5844 /* There should never be more than one step-resume or longjmp-resume
5845 breakpoint per thread, so we should never be setting a new
5846 step_resume_breakpoint when one is already active. */
5847 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5848 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
5851 fprintf_unfiltered (gdb_stdlog
,
5852 "infrun: inserting step-resume breakpoint at %s\n",
5853 paddress (gdbarch
, sr_sal
.pc
));
5855 inferior_thread ()->control
.step_resume_breakpoint
5856 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
);
5860 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5861 struct symtab_and_line sr_sal
,
5862 struct frame_id sr_id
)
5864 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
5869 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
5870 This is used to skip a potential signal handler.
5872 This is called with the interrupted function's frame. The signal
5873 handler, when it returns, will resume the interrupted function at
5877 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5879 struct symtab_and_line sr_sal
;
5880 struct gdbarch
*gdbarch
;
5882 gdb_assert (return_frame
!= NULL
);
5883 init_sal (&sr_sal
); /* initialize to zeros */
5885 gdbarch
= get_frame_arch (return_frame
);
5886 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5887 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5888 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5890 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
5891 get_stack_frame_id (return_frame
),
5895 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
5896 is used to skip a function after stepping into it (for "next" or if
5897 the called function has no debugging information).
5899 The current function has almost always been reached by single
5900 stepping a call or return instruction. NEXT_FRAME belongs to the
5901 current function, and the breakpoint will be set at the caller's
5904 This is a separate function rather than reusing
5905 insert_hp_step_resume_breakpoint_at_frame in order to avoid
5906 get_prev_frame, which may stop prematurely (see the implementation
5907 of frame_unwind_caller_id for an example). */
5910 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5912 struct symtab_and_line sr_sal
;
5913 struct gdbarch
*gdbarch
;
5915 /* We shouldn't have gotten here if we don't know where the call site
5917 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5919 init_sal (&sr_sal
); /* initialize to zeros */
5921 gdbarch
= frame_unwind_caller_arch (next_frame
);
5922 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5923 frame_unwind_caller_pc (next_frame
));
5924 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5925 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5927 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5928 frame_unwind_caller_id (next_frame
));
5931 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5932 new breakpoint at the target of a jmp_buf. The handling of
5933 longjmp-resume uses the same mechanisms used for handling
5934 "step-resume" breakpoints. */
5937 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5939 /* There should never be more than one longjmp-resume breakpoint per
5940 thread, so we should never be setting a new
5941 longjmp_resume_breakpoint when one is already active. */
5942 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
5945 fprintf_unfiltered (gdb_stdlog
,
5946 "infrun: inserting longjmp-resume breakpoint at %s\n",
5947 paddress (gdbarch
, pc
));
5949 inferior_thread ()->control
.exception_resume_breakpoint
=
5950 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5953 /* Insert an exception resume breakpoint. TP is the thread throwing
5954 the exception. The block B is the block of the unwinder debug hook
5955 function. FRAME is the frame corresponding to the call to this
5956 function. SYM is the symbol of the function argument holding the
5957 target PC of the exception. */
5960 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5961 const struct block
*b
,
5962 struct frame_info
*frame
,
5965 volatile struct gdb_exception e
;
5967 /* We want to ignore errors here. */
5968 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5970 struct symbol
*vsym
;
5971 struct value
*value
;
5973 struct breakpoint
*bp
;
5975 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5976 value
= read_var_value (vsym
, frame
);
5977 /* If the value was optimized out, revert to the old behavior. */
5978 if (! value_optimized_out (value
))
5980 handler
= value_as_address (value
);
5983 fprintf_unfiltered (gdb_stdlog
,
5984 "infrun: exception resume at %lx\n",
5985 (unsigned long) handler
);
5987 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5988 handler
, bp_exception_resume
);
5990 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
5993 bp
->thread
= tp
->num
;
5994 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5999 /* A helper for check_exception_resume that sets an
6000 exception-breakpoint based on a SystemTap probe. */
6003 insert_exception_resume_from_probe (struct thread_info
*tp
,
6004 const struct bound_probe
*probe
,
6005 struct frame_info
*frame
)
6007 struct value
*arg_value
;
6009 struct breakpoint
*bp
;
6011 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
6015 handler
= value_as_address (arg_value
);
6018 fprintf_unfiltered (gdb_stdlog
,
6019 "infrun: exception resume at %s\n",
6020 paddress (get_objfile_arch (probe
->objfile
),
6023 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
6024 handler
, bp_exception_resume
);
6025 bp
->thread
= tp
->num
;
6026 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
6029 /* This is called when an exception has been intercepted. Check to
6030 see whether the exception's destination is of interest, and if so,
6031 set an exception resume breakpoint there. */
6034 check_exception_resume (struct execution_control_state
*ecs
,
6035 struct frame_info
*frame
)
6037 volatile struct gdb_exception e
;
6038 struct bound_probe probe
;
6039 struct symbol
*func
;
6041 /* First see if this exception unwinding breakpoint was set via a
6042 SystemTap probe point. If so, the probe has two arguments: the
6043 CFA and the HANDLER. We ignore the CFA, extract the handler, and
6044 set a breakpoint there. */
6045 probe
= find_probe_by_pc (get_frame_pc (frame
));
6048 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
6052 func
= get_frame_function (frame
);
6056 TRY_CATCH (e
, RETURN_MASK_ERROR
)
6058 const struct block
*b
;
6059 struct block_iterator iter
;
6063 /* The exception breakpoint is a thread-specific breakpoint on
6064 the unwinder's debug hook, declared as:
6066 void _Unwind_DebugHook (void *cfa, void *handler);
6068 The CFA argument indicates the frame to which control is
6069 about to be transferred. HANDLER is the destination PC.
6071 We ignore the CFA and set a temporary breakpoint at HANDLER.
6072 This is not extremely efficient but it avoids issues in gdb
6073 with computing the DWARF CFA, and it also works even in weird
6074 cases such as throwing an exception from inside a signal
6077 b
= SYMBOL_BLOCK_VALUE (func
);
6078 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
6080 if (!SYMBOL_IS_ARGUMENT (sym
))
6087 insert_exception_resume_breakpoint (ecs
->event_thread
,
6096 stop_waiting (struct execution_control_state
*ecs
)
6099 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
6101 clear_step_over_info ();
6103 /* Let callers know we don't want to wait for the inferior anymore. */
6104 ecs
->wait_some_more
= 0;
6107 /* Called when we should continue running the inferior, because the
6108 current event doesn't cause a user visible stop. This does the
6109 resuming part; waiting for the next event is done elsewhere. */
6112 keep_going (struct execution_control_state
*ecs
)
6114 /* Make sure normal_stop is called if we get a QUIT handled before
6116 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
6118 /* Save the pc before execution, to compare with pc after stop. */
6119 ecs
->event_thread
->prev_pc
6120 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
6122 if (ecs
->event_thread
->control
.trap_expected
6123 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6125 /* We haven't yet gotten our trap, and either: intercepted a
6126 non-signal event (e.g., a fork); or took a signal which we
6127 are supposed to pass through to the inferior. Simply
6129 discard_cleanups (old_cleanups
);
6130 resume (currently_stepping (ecs
->event_thread
),
6131 ecs
->event_thread
->suspend
.stop_signal
);
6135 volatile struct gdb_exception e
;
6136 struct regcache
*regcache
= get_current_regcache ();
6140 /* Either the trap was not expected, but we are continuing
6141 anyway (if we got a signal, the user asked it be passed to
6144 We got our expected trap, but decided we should resume from
6147 We're going to run this baby now!
6149 Note that insert_breakpoints won't try to re-insert
6150 already inserted breakpoints. Therefore, we don't
6151 care if breakpoints were already inserted, or not. */
6153 /* If we need to step over a breakpoint, and we're not using
6154 displaced stepping to do so, insert all breakpoints
6155 (watchpoints, etc.) but the one we're stepping over, step one
6156 instruction, and then re-insert the breakpoint when that step
6159 remove_bp
= (ecs
->hit_singlestep_breakpoint
6160 || thread_still_needs_step_over (ecs
->event_thread
));
6161 remove_wps
= (ecs
->event_thread
->stepping_over_watchpoint
6162 && !target_have_steppable_watchpoint
);
6164 if (remove_bp
&& !use_displaced_stepping (get_regcache_arch (regcache
)))
6166 set_step_over_info (get_regcache_aspace (regcache
),
6167 regcache_read_pc (regcache
), remove_wps
);
6169 else if (remove_wps
)
6170 set_step_over_info (NULL
, 0, remove_wps
);
6172 clear_step_over_info ();
6174 /* Stop stepping if inserting breakpoints fails. */
6175 TRY_CATCH (e
, RETURN_MASK_ERROR
)
6177 insert_breakpoints ();
6181 exception_print (gdb_stderr
, e
);
6186 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
6188 /* Do not deliver GDB_SIGNAL_TRAP (except when the user
6189 explicitly specifies that such a signal should be delivered
6190 to the target program). Typically, that would occur when a
6191 user is debugging a target monitor on a simulator: the target
6192 monitor sets a breakpoint; the simulator encounters this
6193 breakpoint and halts the simulation handing control to GDB;
6194 GDB, noting that the stop address doesn't map to any known
6195 breakpoint, returns control back to the simulator; the
6196 simulator then delivers the hardware equivalent of a
6197 GDB_SIGNAL_TRAP to the program being debugged. */
6198 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6199 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6200 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6202 discard_cleanups (old_cleanups
);
6203 resume (currently_stepping (ecs
->event_thread
),
6204 ecs
->event_thread
->suspend
.stop_signal
);
6207 prepare_to_wait (ecs
);
6210 /* This function normally comes after a resume, before
6211 handle_inferior_event exits. It takes care of any last bits of
6212 housekeeping, and sets the all-important wait_some_more flag. */
6215 prepare_to_wait (struct execution_control_state
*ecs
)
6218 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
6220 /* This is the old end of the while loop. Let everybody know we
6221 want to wait for the inferior some more and get called again
6223 ecs
->wait_some_more
= 1;
6226 /* We are done with the step range of a step/next/si/ni command.
6227 Called once for each n of a "step n" operation. */
6230 end_stepping_range (struct execution_control_state
*ecs
)
6232 ecs
->event_thread
->control
.stop_step
= 1;
6236 /* Several print_*_reason functions to print why the inferior has stopped.
6237 We always print something when the inferior exits, or receives a signal.
6238 The rest of the cases are dealt with later on in normal_stop and
6239 print_it_typical. Ideally there should be a call to one of these
6240 print_*_reason functions functions from handle_inferior_event each time
6241 stop_waiting is called.
6243 Note that we don't call these directly, instead we delegate that to
6244 the interpreters, through observers. Interpreters then call these
6245 with whatever uiout is right. */
6248 print_end_stepping_range_reason (struct ui_out
*uiout
)
6250 /* For CLI-like interpreters, print nothing. */
6252 if (ui_out_is_mi_like_p (uiout
))
6254 ui_out_field_string (uiout
, "reason",
6255 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
6260 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6262 annotate_signalled ();
6263 if (ui_out_is_mi_like_p (uiout
))
6265 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
6266 ui_out_text (uiout
, "\nProgram terminated with signal ");
6267 annotate_signal_name ();
6268 ui_out_field_string (uiout
, "signal-name",
6269 gdb_signal_to_name (siggnal
));
6270 annotate_signal_name_end ();
6271 ui_out_text (uiout
, ", ");
6272 annotate_signal_string ();
6273 ui_out_field_string (uiout
, "signal-meaning",
6274 gdb_signal_to_string (siggnal
));
6275 annotate_signal_string_end ();
6276 ui_out_text (uiout
, ".\n");
6277 ui_out_text (uiout
, "The program no longer exists.\n");
6281 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
6283 struct inferior
*inf
= current_inferior ();
6284 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
6286 annotate_exited (exitstatus
);
6289 if (ui_out_is_mi_like_p (uiout
))
6290 ui_out_field_string (uiout
, "reason",
6291 async_reason_lookup (EXEC_ASYNC_EXITED
));
6292 ui_out_text (uiout
, "[Inferior ");
6293 ui_out_text (uiout
, plongest (inf
->num
));
6294 ui_out_text (uiout
, " (");
6295 ui_out_text (uiout
, pidstr
);
6296 ui_out_text (uiout
, ") exited with code ");
6297 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
6298 ui_out_text (uiout
, "]\n");
6302 if (ui_out_is_mi_like_p (uiout
))
6304 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
6305 ui_out_text (uiout
, "[Inferior ");
6306 ui_out_text (uiout
, plongest (inf
->num
));
6307 ui_out_text (uiout
, " (");
6308 ui_out_text (uiout
, pidstr
);
6309 ui_out_text (uiout
, ") exited normally]\n");
6314 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
6318 if (siggnal
== GDB_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
6320 struct thread_info
*t
= inferior_thread ();
6322 ui_out_text (uiout
, "\n[");
6323 ui_out_field_string (uiout
, "thread-name",
6324 target_pid_to_str (t
->ptid
));
6325 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
6326 ui_out_text (uiout
, " stopped");
6330 ui_out_text (uiout
, "\nProgram received signal ");
6331 annotate_signal_name ();
6332 if (ui_out_is_mi_like_p (uiout
))
6334 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
6335 ui_out_field_string (uiout
, "signal-name",
6336 gdb_signal_to_name (siggnal
));
6337 annotate_signal_name_end ();
6338 ui_out_text (uiout
, ", ");
6339 annotate_signal_string ();
6340 ui_out_field_string (uiout
, "signal-meaning",
6341 gdb_signal_to_string (siggnal
));
6342 annotate_signal_string_end ();
6344 ui_out_text (uiout
, ".\n");
6348 print_no_history_reason (struct ui_out
*uiout
)
6350 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
6353 /* Print current location without a level number, if we have changed
6354 functions or hit a breakpoint. Print source line if we have one.
6355 bpstat_print contains the logic deciding in detail what to print,
6356 based on the event(s) that just occurred. */
6359 print_stop_event (struct target_waitstatus
*ws
)
6363 int do_frame_printing
= 1;
6364 struct thread_info
*tp
= inferior_thread ();
6366 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
6370 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
6371 should) carry around the function and does (or should) use
6372 that when doing a frame comparison. */
6373 if (tp
->control
.stop_step
6374 && frame_id_eq (tp
->control
.step_frame_id
,
6375 get_frame_id (get_current_frame ()))
6376 && step_start_function
== find_pc_function (stop_pc
))
6378 /* Finished step, just print source line. */
6379 source_flag
= SRC_LINE
;
6383 /* Print location and source line. */
6384 source_flag
= SRC_AND_LOC
;
6387 case PRINT_SRC_AND_LOC
:
6388 /* Print location and source line. */
6389 source_flag
= SRC_AND_LOC
;
6391 case PRINT_SRC_ONLY
:
6392 source_flag
= SRC_LINE
;
6395 /* Something bogus. */
6396 source_flag
= SRC_LINE
;
6397 do_frame_printing
= 0;
6400 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
6403 /* The behavior of this routine with respect to the source
6405 SRC_LINE: Print only source line
6406 LOCATION: Print only location
6407 SRC_AND_LOC: Print location and source line. */
6408 if (do_frame_printing
)
6409 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
6411 /* Display the auto-display expressions. */
6415 /* Here to return control to GDB when the inferior stops for real.
6416 Print appropriate messages, remove breakpoints, give terminal our modes.
6418 STOP_PRINT_FRAME nonzero means print the executing frame
6419 (pc, function, args, file, line number and line text).
6420 BREAKPOINTS_FAILED nonzero means stop was due to error
6421 attempting to insert breakpoints. */
6426 struct target_waitstatus last
;
6428 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
6430 get_last_target_status (&last_ptid
, &last
);
6432 /* If an exception is thrown from this point on, make sure to
6433 propagate GDB's knowledge of the executing state to the
6434 frontend/user running state. A QUIT is an easy exception to see
6435 here, so do this before any filtered output. */
6437 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
6438 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6439 && last
.kind
!= TARGET_WAITKIND_EXITED
6440 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6441 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
6443 /* As we're presenting a stop, and potentially removing breakpoints,
6444 update the thread list so we can tell whether there are threads
6445 running on the target. With target remote, for example, we can
6446 only learn about new threads when we explicitly update the thread
6447 list. Do this before notifying the interpreters about signal
6448 stops, end of stepping ranges, etc., so that the "new thread"
6449 output is emitted before e.g., "Program received signal FOO",
6450 instead of after. */
6451 update_thread_list ();
6453 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
6454 observer_notify_signal_received (inferior_thread ()->suspend
.stop_signal
);
6456 /* As with the notification of thread events, we want to delay
6457 notifying the user that we've switched thread context until
6458 the inferior actually stops.
6460 There's no point in saying anything if the inferior has exited.
6461 Note that SIGNALLED here means "exited with a signal", not
6462 "received a signal".
6464 Also skip saying anything in non-stop mode. In that mode, as we
6465 don't want GDB to switch threads behind the user's back, to avoid
6466 races where the user is typing a command to apply to thread x,
6467 but GDB switches to thread y before the user finishes entering
6468 the command, fetch_inferior_event installs a cleanup to restore
6469 the current thread back to the thread the user had selected right
6470 after this event is handled, so we're not really switching, only
6471 informing of a stop. */
6473 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
6474 && target_has_execution
6475 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6476 && last
.kind
!= TARGET_WAITKIND_EXITED
6477 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
6479 target_terminal_ours_for_output ();
6480 printf_filtered (_("[Switching to %s]\n"),
6481 target_pid_to_str (inferior_ptid
));
6482 annotate_thread_changed ();
6483 previous_inferior_ptid
= inferior_ptid
;
6486 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
6488 gdb_assert (sync_execution
|| !target_can_async_p ());
6490 target_terminal_ours_for_output ();
6491 printf_filtered (_("No unwaited-for children left.\n"));
6494 /* Note: this depends on the update_thread_list call above. */
6495 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
6497 if (remove_breakpoints ())
6499 target_terminal_ours_for_output ();
6500 printf_filtered (_("Cannot remove breakpoints because "
6501 "program is no longer writable.\nFurther "
6502 "execution is probably impossible.\n"));
6506 /* If an auto-display called a function and that got a signal,
6507 delete that auto-display to avoid an infinite recursion. */
6509 if (stopped_by_random_signal
)
6510 disable_current_display ();
6512 /* Notify observers if we finished a "step"-like command, etc. */
6513 if (target_has_execution
6514 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
6515 && last
.kind
!= TARGET_WAITKIND_EXITED
6516 && inferior_thread ()->control
.stop_step
)
6518 /* But not if in the middle of doing a "step n" operation for
6520 if (inferior_thread ()->step_multi
)
6523 observer_notify_end_stepping_range ();
6526 target_terminal_ours ();
6527 async_enable_stdin ();
6529 /* Set the current source location. This will also happen if we
6530 display the frame below, but the current SAL will be incorrect
6531 during a user hook-stop function. */
6532 if (has_stack_frames () && !stop_stack_dummy
)
6533 set_current_sal_from_frame (get_current_frame ());
6535 /* Let the user/frontend see the threads as stopped, but do nothing
6536 if the thread was running an infcall. We may be e.g., evaluating
6537 a breakpoint condition. In that case, the thread had state
6538 THREAD_RUNNING before the infcall, and shall remain set to
6539 running, all without informing the user/frontend about state
6540 transition changes. If this is actually a call command, then the
6541 thread was originally already stopped, so there's no state to
6543 if (target_has_execution
&& inferior_thread ()->control
.in_infcall
)
6544 discard_cleanups (old_chain
);
6546 do_cleanups (old_chain
);
6548 /* Look up the hook_stop and run it (CLI internally handles problem
6549 of stop_command's pre-hook not existing). */
6551 catch_errors (hook_stop_stub
, stop_command
,
6552 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
6554 if (!has_stack_frames ())
6557 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
6558 || last
.kind
== TARGET_WAITKIND_EXITED
)
6561 /* Select innermost stack frame - i.e., current frame is frame 0,
6562 and current location is based on that.
6563 Don't do this on return from a stack dummy routine,
6564 or if the program has exited. */
6566 if (!stop_stack_dummy
)
6568 select_frame (get_current_frame ());
6570 /* If --batch-silent is enabled then there's no need to print the current
6571 source location, and to try risks causing an error message about
6572 missing source files. */
6573 if (stop_print_frame
&& !batch_silent
)
6574 print_stop_event (&last
);
6577 /* Save the function value return registers, if we care.
6578 We might be about to restore their previous contents. */
6579 if (inferior_thread ()->control
.proceed_to_finish
6580 && execution_direction
!= EXEC_REVERSE
)
6582 /* This should not be necessary. */
6584 regcache_xfree (stop_registers
);
6586 /* NB: The copy goes through to the target picking up the value of
6587 all the registers. */
6588 stop_registers
= regcache_dup (get_current_regcache ());
6591 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
6593 /* Pop the empty frame that contains the stack dummy.
6594 This also restores inferior state prior to the call
6595 (struct infcall_suspend_state). */
6596 struct frame_info
*frame
= get_current_frame ();
6598 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
6600 /* frame_pop() calls reinit_frame_cache as the last thing it
6601 does which means there's currently no selected frame. We
6602 don't need to re-establish a selected frame if the dummy call
6603 returns normally, that will be done by
6604 restore_infcall_control_state. However, we do have to handle
6605 the case where the dummy call is returning after being
6606 stopped (e.g. the dummy call previously hit a breakpoint).
6607 We can't know which case we have so just always re-establish
6608 a selected frame here. */
6609 select_frame (get_current_frame ());
6613 annotate_stopped ();
6615 /* Suppress the stop observer if we're in the middle of:
6617 - a step n (n > 1), as there still more steps to be done.
6619 - a "finish" command, as the observer will be called in
6620 finish_command_continuation, so it can include the inferior
6621 function's return value.
6623 - calling an inferior function, as we pretend we inferior didn't
6624 run at all. The return value of the call is handled by the
6625 expression evaluator, through call_function_by_hand. */
6627 if (!target_has_execution
6628 || last
.kind
== TARGET_WAITKIND_SIGNALLED
6629 || last
.kind
== TARGET_WAITKIND_EXITED
6630 || last
.kind
== TARGET_WAITKIND_NO_RESUMED
6631 || (!(inferior_thread ()->step_multi
6632 && inferior_thread ()->control
.stop_step
)
6633 && !(inferior_thread ()->control
.stop_bpstat
6634 && inferior_thread ()->control
.proceed_to_finish
)
6635 && !inferior_thread ()->control
.in_infcall
))
6637 if (!ptid_equal (inferior_ptid
, null_ptid
))
6638 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
6641 observer_notify_normal_stop (NULL
, stop_print_frame
);
6644 if (target_has_execution
)
6646 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
6647 && last
.kind
!= TARGET_WAITKIND_EXITED
)
6648 /* Delete the breakpoint we stopped at, if it wants to be deleted.
6649 Delete any breakpoint that is to be deleted at the next stop. */
6650 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
6653 /* Try to get rid of automatically added inferiors that are no
6654 longer needed. Keeping those around slows down things linearly.
6655 Note that this never removes the current inferior. */
6660 hook_stop_stub (void *cmd
)
6662 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
6667 signal_stop_state (int signo
)
6669 return signal_stop
[signo
];
6673 signal_print_state (int signo
)
6675 return signal_print
[signo
];
6679 signal_pass_state (int signo
)
6681 return signal_program
[signo
];
6685 signal_cache_update (int signo
)
6689 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
6690 signal_cache_update (signo
);
6695 signal_pass
[signo
] = (signal_stop
[signo
] == 0
6696 && signal_print
[signo
] == 0
6697 && signal_program
[signo
] == 1
6698 && signal_catch
[signo
] == 0);
6702 signal_stop_update (int signo
, int state
)
6704 int ret
= signal_stop
[signo
];
6706 signal_stop
[signo
] = state
;
6707 signal_cache_update (signo
);
6712 signal_print_update (int signo
, int state
)
6714 int ret
= signal_print
[signo
];
6716 signal_print
[signo
] = state
;
6717 signal_cache_update (signo
);
6722 signal_pass_update (int signo
, int state
)
6724 int ret
= signal_program
[signo
];
6726 signal_program
[signo
] = state
;
6727 signal_cache_update (signo
);
6731 /* Update the global 'signal_catch' from INFO and notify the
6735 signal_catch_update (const unsigned int *info
)
6739 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
6740 signal_catch
[i
] = info
[i
] > 0;
6741 signal_cache_update (-1);
6742 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6746 sig_print_header (void)
6748 printf_filtered (_("Signal Stop\tPrint\tPass "
6749 "to program\tDescription\n"));
6753 sig_print_info (enum gdb_signal oursig
)
6755 const char *name
= gdb_signal_to_name (oursig
);
6756 int name_padding
= 13 - strlen (name
);
6758 if (name_padding
<= 0)
6761 printf_filtered ("%s", name
);
6762 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
6763 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
6764 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
6765 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
6766 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
6769 /* Specify how various signals in the inferior should be handled. */
6772 handle_command (char *args
, int from_tty
)
6775 int digits
, wordlen
;
6776 int sigfirst
, signum
, siglast
;
6777 enum gdb_signal oursig
;
6780 unsigned char *sigs
;
6781 struct cleanup
*old_chain
;
6785 error_no_arg (_("signal to handle"));
6788 /* Allocate and zero an array of flags for which signals to handle. */
6790 nsigs
= (int) GDB_SIGNAL_LAST
;
6791 sigs
= (unsigned char *) alloca (nsigs
);
6792 memset (sigs
, 0, nsigs
);
6794 /* Break the command line up into args. */
6796 argv
= gdb_buildargv (args
);
6797 old_chain
= make_cleanup_freeargv (argv
);
6799 /* Walk through the args, looking for signal oursigs, signal names, and
6800 actions. Signal numbers and signal names may be interspersed with
6801 actions, with the actions being performed for all signals cumulatively
6802 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6804 while (*argv
!= NULL
)
6806 wordlen
= strlen (*argv
);
6807 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6811 sigfirst
= siglast
= -1;
6813 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6815 /* Apply action to all signals except those used by the
6816 debugger. Silently skip those. */
6819 siglast
= nsigs
- 1;
6821 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6823 SET_SIGS (nsigs
, sigs
, signal_stop
);
6824 SET_SIGS (nsigs
, sigs
, signal_print
);
6826 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6828 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6830 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6832 SET_SIGS (nsigs
, sigs
, signal_print
);
6834 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6836 SET_SIGS (nsigs
, sigs
, signal_program
);
6838 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6840 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6842 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6844 SET_SIGS (nsigs
, sigs
, signal_program
);
6846 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6848 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6849 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6851 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6853 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6855 else if (digits
> 0)
6857 /* It is numeric. The numeric signal refers to our own
6858 internal signal numbering from target.h, not to host/target
6859 signal number. This is a feature; users really should be
6860 using symbolic names anyway, and the common ones like
6861 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6863 sigfirst
= siglast
= (int)
6864 gdb_signal_from_command (atoi (*argv
));
6865 if ((*argv
)[digits
] == '-')
6868 gdb_signal_from_command (atoi ((*argv
) + digits
+ 1));
6870 if (sigfirst
> siglast
)
6872 /* Bet he didn't figure we'd think of this case... */
6880 oursig
= gdb_signal_from_name (*argv
);
6881 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
6883 sigfirst
= siglast
= (int) oursig
;
6887 /* Not a number and not a recognized flag word => complain. */
6888 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6892 /* If any signal numbers or symbol names were found, set flags for
6893 which signals to apply actions to. */
6895 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6897 switch ((enum gdb_signal
) signum
)
6899 case GDB_SIGNAL_TRAP
:
6900 case GDB_SIGNAL_INT
:
6901 if (!allsigs
&& !sigs
[signum
])
6903 if (query (_("%s is used by the debugger.\n\
6904 Are you sure you want to change it? "),
6905 gdb_signal_to_name ((enum gdb_signal
) signum
)))
6911 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6912 gdb_flush (gdb_stdout
);
6917 case GDB_SIGNAL_DEFAULT
:
6918 case GDB_SIGNAL_UNKNOWN
:
6919 /* Make sure that "all" doesn't print these. */
6930 for (signum
= 0; signum
< nsigs
; signum
++)
6933 signal_cache_update (-1);
6934 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
6935 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
6939 /* Show the results. */
6940 sig_print_header ();
6941 for (; signum
< nsigs
; signum
++)
6943 sig_print_info (signum
);
6949 do_cleanups (old_chain
);
6952 /* Complete the "handle" command. */
6954 static VEC (char_ptr
) *
6955 handle_completer (struct cmd_list_element
*ignore
,
6956 const char *text
, const char *word
)
6958 VEC (char_ptr
) *vec_signals
, *vec_keywords
, *return_val
;
6959 static const char * const keywords
[] =
6973 vec_signals
= signal_completer (ignore
, text
, word
);
6974 vec_keywords
= complete_on_enum (keywords
, word
, word
);
6976 return_val
= VEC_merge (char_ptr
, vec_signals
, vec_keywords
);
6977 VEC_free (char_ptr
, vec_signals
);
6978 VEC_free (char_ptr
, vec_keywords
);
6983 xdb_handle_command (char *args
, int from_tty
)
6986 struct cleanup
*old_chain
;
6989 error_no_arg (_("xdb command"));
6991 /* Break the command line up into args. */
6993 argv
= gdb_buildargv (args
);
6994 old_chain
= make_cleanup_freeargv (argv
);
6995 if (argv
[1] != (char *) NULL
)
7000 bufLen
= strlen (argv
[0]) + 20;
7001 argBuf
= (char *) xmalloc (bufLen
);
7005 enum gdb_signal oursig
;
7007 oursig
= gdb_signal_from_name (argv
[0]);
7008 memset (argBuf
, 0, bufLen
);
7009 if (strcmp (argv
[1], "Q") == 0)
7010 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
7013 if (strcmp (argv
[1], "s") == 0)
7015 if (!signal_stop
[oursig
])
7016 sprintf (argBuf
, "%s %s", argv
[0], "stop");
7018 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
7020 else if (strcmp (argv
[1], "i") == 0)
7022 if (!signal_program
[oursig
])
7023 sprintf (argBuf
, "%s %s", argv
[0], "pass");
7025 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
7027 else if (strcmp (argv
[1], "r") == 0)
7029 if (!signal_print
[oursig
])
7030 sprintf (argBuf
, "%s %s", argv
[0], "print");
7032 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
7038 handle_command (argBuf
, from_tty
);
7040 printf_filtered (_("Invalid signal handling flag.\n"));
7045 do_cleanups (old_chain
);
7049 gdb_signal_from_command (int num
)
7051 if (num
>= 1 && num
<= 15)
7052 return (enum gdb_signal
) num
;
7053 error (_("Only signals 1-15 are valid as numeric signals.\n\
7054 Use \"info signals\" for a list of symbolic signals."));
7057 /* Print current contents of the tables set by the handle command.
7058 It is possible we should just be printing signals actually used
7059 by the current target (but for things to work right when switching
7060 targets, all signals should be in the signal tables). */
7063 signals_info (char *signum_exp
, int from_tty
)
7065 enum gdb_signal oursig
;
7067 sig_print_header ();
7071 /* First see if this is a symbol name. */
7072 oursig
= gdb_signal_from_name (signum_exp
);
7073 if (oursig
== GDB_SIGNAL_UNKNOWN
)
7075 /* No, try numeric. */
7077 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
7079 sig_print_info (oursig
);
7083 printf_filtered ("\n");
7084 /* These ugly casts brought to you by the native VAX compiler. */
7085 for (oursig
= GDB_SIGNAL_FIRST
;
7086 (int) oursig
< (int) GDB_SIGNAL_LAST
;
7087 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
7091 if (oursig
!= GDB_SIGNAL_UNKNOWN
7092 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
7093 sig_print_info (oursig
);
7096 printf_filtered (_("\nUse the \"handle\" command "
7097 "to change these tables.\n"));
7100 /* Check if it makes sense to read $_siginfo from the current thread
7101 at this point. If not, throw an error. */
7104 validate_siginfo_access (void)
7106 /* No current inferior, no siginfo. */
7107 if (ptid_equal (inferior_ptid
, null_ptid
))
7108 error (_("No thread selected."));
7110 /* Don't try to read from a dead thread. */
7111 if (is_exited (inferior_ptid
))
7112 error (_("The current thread has terminated"));
7114 /* ... or from a spinning thread. */
7115 if (is_running (inferior_ptid
))
7116 error (_("Selected thread is running."));
7119 /* The $_siginfo convenience variable is a bit special. We don't know
7120 for sure the type of the value until we actually have a chance to
7121 fetch the data. The type can change depending on gdbarch, so it is
7122 also dependent on which thread you have selected.
7124 1. making $_siginfo be an internalvar that creates a new value on
7127 2. making the value of $_siginfo be an lval_computed value. */
7129 /* This function implements the lval_computed support for reading a
7133 siginfo_value_read (struct value
*v
)
7135 LONGEST transferred
;
7137 validate_siginfo_access ();
7140 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
7142 value_contents_all_raw (v
),
7144 TYPE_LENGTH (value_type (v
)));
7146 if (transferred
!= TYPE_LENGTH (value_type (v
)))
7147 error (_("Unable to read siginfo"));
7150 /* This function implements the lval_computed support for writing a
7154 siginfo_value_write (struct value
*v
, struct value
*fromval
)
7156 LONGEST transferred
;
7158 validate_siginfo_access ();
7160 transferred
= target_write (¤t_target
,
7161 TARGET_OBJECT_SIGNAL_INFO
,
7163 value_contents_all_raw (fromval
),
7165 TYPE_LENGTH (value_type (fromval
)));
7167 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
7168 error (_("Unable to write siginfo"));
7171 static const struct lval_funcs siginfo_value_funcs
=
7177 /* Return a new value with the correct type for the siginfo object of
7178 the current thread using architecture GDBARCH. Return a void value
7179 if there's no object available. */
7181 static struct value
*
7182 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
7185 if (target_has_stack
7186 && !ptid_equal (inferior_ptid
, null_ptid
)
7187 && gdbarch_get_siginfo_type_p (gdbarch
))
7189 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7191 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
7194 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
7198 /* infcall_suspend_state contains state about the program itself like its
7199 registers and any signal it received when it last stopped.
7200 This state must be restored regardless of how the inferior function call
7201 ends (either successfully, or after it hits a breakpoint or signal)
7202 if the program is to properly continue where it left off. */
7204 struct infcall_suspend_state
7206 struct thread_suspend_state thread_suspend
;
7207 #if 0 /* Currently unused and empty structures are not valid C. */
7208 struct inferior_suspend_state inferior_suspend
;
7213 struct regcache
*registers
;
7215 /* Format of SIGINFO_DATA or NULL if it is not present. */
7216 struct gdbarch
*siginfo_gdbarch
;
7218 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
7219 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
7220 content would be invalid. */
7221 gdb_byte
*siginfo_data
;
7224 struct infcall_suspend_state
*
7225 save_infcall_suspend_state (void)
7227 struct infcall_suspend_state
*inf_state
;
7228 struct thread_info
*tp
= inferior_thread ();
7230 struct inferior
*inf
= current_inferior ();
7232 struct regcache
*regcache
= get_current_regcache ();
7233 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7234 gdb_byte
*siginfo_data
= NULL
;
7236 if (gdbarch_get_siginfo_type_p (gdbarch
))
7238 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7239 size_t len
= TYPE_LENGTH (type
);
7240 struct cleanup
*back_to
;
7242 siginfo_data
= xmalloc (len
);
7243 back_to
= make_cleanup (xfree
, siginfo_data
);
7245 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7246 siginfo_data
, 0, len
) == len
)
7247 discard_cleanups (back_to
);
7250 /* Errors ignored. */
7251 do_cleanups (back_to
);
7252 siginfo_data
= NULL
;
7256 inf_state
= XCNEW (struct infcall_suspend_state
);
7260 inf_state
->siginfo_gdbarch
= gdbarch
;
7261 inf_state
->siginfo_data
= siginfo_data
;
7264 inf_state
->thread_suspend
= tp
->suspend
;
7265 #if 0 /* Currently unused and empty structures are not valid C. */
7266 inf_state
->inferior_suspend
= inf
->suspend
;
7269 /* run_inferior_call will not use the signal due to its `proceed' call with
7270 GDB_SIGNAL_0 anyway. */
7271 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7273 inf_state
->stop_pc
= stop_pc
;
7275 inf_state
->registers
= regcache_dup (regcache
);
7280 /* Restore inferior session state to INF_STATE. */
7283 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7285 struct thread_info
*tp
= inferior_thread ();
7287 struct inferior
*inf
= current_inferior ();
7289 struct regcache
*regcache
= get_current_regcache ();
7290 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
7292 tp
->suspend
= inf_state
->thread_suspend
;
7293 #if 0 /* Currently unused and empty structures are not valid C. */
7294 inf
->suspend
= inf_state
->inferior_suspend
;
7297 stop_pc
= inf_state
->stop_pc
;
7299 if (inf_state
->siginfo_gdbarch
== gdbarch
)
7301 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
7303 /* Errors ignored. */
7304 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
7305 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
7308 /* The inferior can be gone if the user types "print exit(0)"
7309 (and perhaps other times). */
7310 if (target_has_execution
)
7311 /* NB: The register write goes through to the target. */
7312 regcache_cpy (regcache
, inf_state
->registers
);
7314 discard_infcall_suspend_state (inf_state
);
7318 do_restore_infcall_suspend_state_cleanup (void *state
)
7320 restore_infcall_suspend_state (state
);
7324 make_cleanup_restore_infcall_suspend_state
7325 (struct infcall_suspend_state
*inf_state
)
7327 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
7331 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
7333 regcache_xfree (inf_state
->registers
);
7334 xfree (inf_state
->siginfo_data
);
7339 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
7341 return inf_state
->registers
;
7344 /* infcall_control_state contains state regarding gdb's control of the
7345 inferior itself like stepping control. It also contains session state like
7346 the user's currently selected frame. */
7348 struct infcall_control_state
7350 struct thread_control_state thread_control
;
7351 struct inferior_control_state inferior_control
;
7354 enum stop_stack_kind stop_stack_dummy
;
7355 int stopped_by_random_signal
;
7356 int stop_after_trap
;
7358 /* ID if the selected frame when the inferior function call was made. */
7359 struct frame_id selected_frame_id
;
7362 /* Save all of the information associated with the inferior<==>gdb
7365 struct infcall_control_state
*
7366 save_infcall_control_state (void)
7368 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
7369 struct thread_info
*tp
= inferior_thread ();
7370 struct inferior
*inf
= current_inferior ();
7372 inf_status
->thread_control
= tp
->control
;
7373 inf_status
->inferior_control
= inf
->control
;
7375 tp
->control
.step_resume_breakpoint
= NULL
;
7376 tp
->control
.exception_resume_breakpoint
= NULL
;
7378 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
7379 chain. If caller's caller is walking the chain, they'll be happier if we
7380 hand them back the original chain when restore_infcall_control_state is
7382 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
7385 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
7386 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
7387 inf_status
->stop_after_trap
= stop_after_trap
;
7389 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
7395 restore_selected_frame (void *args
)
7397 struct frame_id
*fid
= (struct frame_id
*) args
;
7398 struct frame_info
*frame
;
7400 frame
= frame_find_by_id (*fid
);
7402 /* If inf_status->selected_frame_id is NULL, there was no previously
7406 warning (_("Unable to restore previously selected frame."));
7410 select_frame (frame
);
7415 /* Restore inferior session state to INF_STATUS. */
7418 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
7420 struct thread_info
*tp
= inferior_thread ();
7421 struct inferior
*inf
= current_inferior ();
7423 if (tp
->control
.step_resume_breakpoint
)
7424 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
7426 if (tp
->control
.exception_resume_breakpoint
)
7427 tp
->control
.exception_resume_breakpoint
->disposition
7428 = disp_del_at_next_stop
;
7430 /* Handle the bpstat_copy of the chain. */
7431 bpstat_clear (&tp
->control
.stop_bpstat
);
7433 tp
->control
= inf_status
->thread_control
;
7434 inf
->control
= inf_status
->inferior_control
;
7437 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
7438 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
7439 stop_after_trap
= inf_status
->stop_after_trap
;
7441 if (target_has_stack
)
7443 /* The point of catch_errors is that if the stack is clobbered,
7444 walking the stack might encounter a garbage pointer and
7445 error() trying to dereference it. */
7447 (restore_selected_frame
, &inf_status
->selected_frame_id
,
7448 "Unable to restore previously selected frame:\n",
7449 RETURN_MASK_ERROR
) == 0)
7450 /* Error in restoring the selected frame. Select the innermost
7452 select_frame (get_current_frame ());
7459 do_restore_infcall_control_state_cleanup (void *sts
)
7461 restore_infcall_control_state (sts
);
7465 make_cleanup_restore_infcall_control_state
7466 (struct infcall_control_state
*inf_status
)
7468 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
7472 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
7474 if (inf_status
->thread_control
.step_resume_breakpoint
)
7475 inf_status
->thread_control
.step_resume_breakpoint
->disposition
7476 = disp_del_at_next_stop
;
7478 if (inf_status
->thread_control
.exception_resume_breakpoint
)
7479 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
7480 = disp_del_at_next_stop
;
7482 /* See save_infcall_control_state for info on stop_bpstat. */
7483 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
7488 /* restore_inferior_ptid() will be used by the cleanup machinery
7489 to restore the inferior_ptid value saved in a call to
7490 save_inferior_ptid(). */
7493 restore_inferior_ptid (void *arg
)
7495 ptid_t
*saved_ptid_ptr
= arg
;
7497 inferior_ptid
= *saved_ptid_ptr
;
7501 /* Save the value of inferior_ptid so that it may be restored by a
7502 later call to do_cleanups(). Returns the struct cleanup pointer
7503 needed for later doing the cleanup. */
7506 save_inferior_ptid (void)
7508 ptid_t
*saved_ptid_ptr
;
7510 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
7511 *saved_ptid_ptr
= inferior_ptid
;
7512 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
7518 clear_exit_convenience_vars (void)
7520 clear_internalvar (lookup_internalvar ("_exitsignal"));
7521 clear_internalvar (lookup_internalvar ("_exitcode"));
7525 /* User interface for reverse debugging:
7526 Set exec-direction / show exec-direction commands
7527 (returns error unless target implements to_set_exec_direction method). */
7529 int execution_direction
= EXEC_FORWARD
;
7530 static const char exec_forward
[] = "forward";
7531 static const char exec_reverse
[] = "reverse";
7532 static const char *exec_direction
= exec_forward
;
7533 static const char *const exec_direction_names
[] = {
7540 set_exec_direction_func (char *args
, int from_tty
,
7541 struct cmd_list_element
*cmd
)
7543 if (target_can_execute_reverse
)
7545 if (!strcmp (exec_direction
, exec_forward
))
7546 execution_direction
= EXEC_FORWARD
;
7547 else if (!strcmp (exec_direction
, exec_reverse
))
7548 execution_direction
= EXEC_REVERSE
;
7552 exec_direction
= exec_forward
;
7553 error (_("Target does not support this operation."));
7558 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
7559 struct cmd_list_element
*cmd
, const char *value
)
7561 switch (execution_direction
) {
7563 fprintf_filtered (out
, _("Forward.\n"));
7566 fprintf_filtered (out
, _("Reverse.\n"));
7569 internal_error (__FILE__
, __LINE__
,
7570 _("bogus execution_direction value: %d"),
7571 (int) execution_direction
);
7576 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
7577 struct cmd_list_element
*c
, const char *value
)
7579 fprintf_filtered (file
, _("Resuming the execution of threads "
7580 "of all processes is %s.\n"), value
);
7583 /* Implementation of `siginfo' variable. */
7585 static const struct internalvar_funcs siginfo_funcs
=
7593 _initialize_infrun (void)
7597 struct cmd_list_element
*c
;
7599 add_info ("signals", signals_info
, _("\
7600 What debugger does when program gets various signals.\n\
7601 Specify a signal as argument to print info on that signal only."));
7602 add_info_alias ("handle", "signals", 0);
7604 c
= add_com ("handle", class_run
, handle_command
, _("\
7605 Specify how to handle signals.\n\
7606 Usage: handle SIGNAL [ACTIONS]\n\
7607 Args are signals and actions to apply to those signals.\n\
7608 If no actions are specified, the current settings for the specified signals\n\
7609 will be displayed instead.\n\
7611 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7612 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7613 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7614 The special arg \"all\" is recognized to mean all signals except those\n\
7615 used by the debugger, typically SIGTRAP and SIGINT.\n\
7617 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
7618 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
7619 Stop means reenter debugger if this signal happens (implies print).\n\
7620 Print means print a message if this signal happens.\n\
7621 Pass means let program see this signal; otherwise program doesn't know.\n\
7622 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7623 Pass and Stop may be combined.\n\
7625 Multiple signals may be specified. Signal numbers and signal names\n\
7626 may be interspersed with actions, with the actions being performed for\n\
7627 all signals cumulatively specified."));
7628 set_cmd_completer (c
, handle_completer
);
7632 add_com ("lz", class_info
, signals_info
, _("\
7633 What debugger does when program gets various signals.\n\
7634 Specify a signal as argument to print info on that signal only."));
7635 add_com ("z", class_run
, xdb_handle_command
, _("\
7636 Specify how to handle a signal.\n\
7637 Args are signals and actions to apply to those signals.\n\
7638 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
7639 from 1-15 are allowed for compatibility with old versions of GDB.\n\
7640 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
7641 The special arg \"all\" is recognized to mean all signals except those\n\
7642 used by the debugger, typically SIGTRAP and SIGINT.\n\
7643 Recognized actions include \"s\" (toggles between stop and nostop),\n\
7644 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
7645 nopass), \"Q\" (noprint)\n\
7646 Stop means reenter debugger if this signal happens (implies print).\n\
7647 Print means print a message if this signal happens.\n\
7648 Pass means let program see this signal; otherwise program doesn't know.\n\
7649 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
7650 Pass and Stop may be combined."));
7654 stop_command
= add_cmd ("stop", class_obscure
,
7655 not_just_help_class_command
, _("\
7656 There is no `stop' command, but you can set a hook on `stop'.\n\
7657 This allows you to set a list of commands to be run each time execution\n\
7658 of the program stops."), &cmdlist
);
7660 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
7661 Set inferior debugging."), _("\
7662 Show inferior debugging."), _("\
7663 When non-zero, inferior specific debugging is enabled."),
7666 &setdebuglist
, &showdebuglist
);
7668 add_setshow_boolean_cmd ("displaced", class_maintenance
,
7669 &debug_displaced
, _("\
7670 Set displaced stepping debugging."), _("\
7671 Show displaced stepping debugging."), _("\
7672 When non-zero, displaced stepping specific debugging is enabled."),
7674 show_debug_displaced
,
7675 &setdebuglist
, &showdebuglist
);
7677 add_setshow_boolean_cmd ("non-stop", no_class
,
7679 Set whether gdb controls the inferior in non-stop mode."), _("\
7680 Show whether gdb controls the inferior in non-stop mode."), _("\
7681 When debugging a multi-threaded program and this setting is\n\
7682 off (the default, also called all-stop mode), when one thread stops\n\
7683 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
7684 all other threads in the program while you interact with the thread of\n\
7685 interest. When you continue or step a thread, you can allow the other\n\
7686 threads to run, or have them remain stopped, but while you inspect any\n\
7687 thread's state, all threads stop.\n\
7689 In non-stop mode, when one thread stops, other threads can continue\n\
7690 to run freely. You'll be able to step each thread independently,\n\
7691 leave it stopped or free to run as needed."),
7697 numsigs
= (int) GDB_SIGNAL_LAST
;
7698 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7699 signal_print
= (unsigned char *)
7700 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7701 signal_program
= (unsigned char *)
7702 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7703 signal_catch
= (unsigned char *)
7704 xmalloc (sizeof (signal_catch
[0]) * numsigs
);
7705 signal_pass
= (unsigned char *)
7706 xmalloc (sizeof (signal_pass
[0]) * numsigs
);
7707 for (i
= 0; i
< numsigs
; i
++)
7710 signal_print
[i
] = 1;
7711 signal_program
[i
] = 1;
7712 signal_catch
[i
] = 0;
7715 /* Signals caused by debugger's own actions
7716 should not be given to the program afterwards. */
7717 signal_program
[GDB_SIGNAL_TRAP
] = 0;
7718 signal_program
[GDB_SIGNAL_INT
] = 0;
7720 /* Signals that are not errors should not normally enter the debugger. */
7721 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
7722 signal_print
[GDB_SIGNAL_ALRM
] = 0;
7723 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
7724 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
7725 signal_stop
[GDB_SIGNAL_PROF
] = 0;
7726 signal_print
[GDB_SIGNAL_PROF
] = 0;
7727 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
7728 signal_print
[GDB_SIGNAL_CHLD
] = 0;
7729 signal_stop
[GDB_SIGNAL_IO
] = 0;
7730 signal_print
[GDB_SIGNAL_IO
] = 0;
7731 signal_stop
[GDB_SIGNAL_POLL
] = 0;
7732 signal_print
[GDB_SIGNAL_POLL
] = 0;
7733 signal_stop
[GDB_SIGNAL_URG
] = 0;
7734 signal_print
[GDB_SIGNAL_URG
] = 0;
7735 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
7736 signal_print
[GDB_SIGNAL_WINCH
] = 0;
7737 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
7738 signal_print
[GDB_SIGNAL_PRIO
] = 0;
7740 /* These signals are used internally by user-level thread
7741 implementations. (See signal(5) on Solaris.) Like the above
7742 signals, a healthy program receives and handles them as part of
7743 its normal operation. */
7744 signal_stop
[GDB_SIGNAL_LWP
] = 0;
7745 signal_print
[GDB_SIGNAL_LWP
] = 0;
7746 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
7747 signal_print
[GDB_SIGNAL_WAITING
] = 0;
7748 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
7749 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
7751 /* Update cached state. */
7752 signal_cache_update (-1);
7754 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7755 &stop_on_solib_events
, _("\
7756 Set stopping for shared library events."), _("\
7757 Show stopping for shared library events."), _("\
7758 If nonzero, gdb will give control to the user when the dynamic linker\n\
7759 notifies gdb of shared library events. The most common event of interest\n\
7760 to the user would be loading/unloading of a new library."),
7761 set_stop_on_solib_events
,
7762 show_stop_on_solib_events
,
7763 &setlist
, &showlist
);
7765 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7766 follow_fork_mode_kind_names
,
7767 &follow_fork_mode_string
, _("\
7768 Set debugger response to a program call of fork or vfork."), _("\
7769 Show debugger response to a program call of fork or vfork."), _("\
7770 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7771 parent - the original process is debugged after a fork\n\
7772 child - the new process is debugged after a fork\n\
7773 The unfollowed process will continue to run.\n\
7774 By default, the debugger will follow the parent process."),
7776 show_follow_fork_mode_string
,
7777 &setlist
, &showlist
);
7779 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7780 follow_exec_mode_names
,
7781 &follow_exec_mode_string
, _("\
7782 Set debugger response to a program call of exec."), _("\
7783 Show debugger response to a program call of exec."), _("\
7784 An exec call replaces the program image of a process.\n\
7786 follow-exec-mode can be:\n\
7788 new - the debugger creates a new inferior and rebinds the process\n\
7789 to this new inferior. The program the process was running before\n\
7790 the exec call can be restarted afterwards by restarting the original\n\
7793 same - the debugger keeps the process bound to the same inferior.\n\
7794 The new executable image replaces the previous executable loaded in\n\
7795 the inferior. Restarting the inferior after the exec call restarts\n\
7796 the executable the process was running after the exec call.\n\
7798 By default, the debugger will use the same inferior."),
7800 show_follow_exec_mode_string
,
7801 &setlist
, &showlist
);
7803 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7804 scheduler_enums
, &scheduler_mode
, _("\
7805 Set mode for locking scheduler during execution."), _("\
7806 Show mode for locking scheduler during execution."), _("\
7807 off == no locking (threads may preempt at any time)\n\
7808 on == full locking (no thread except the current thread may run)\n\
7809 step == scheduler locked during every single-step operation.\n\
7810 In this mode, no other thread may run during a step command.\n\
7811 Other threads may run while stepping over a function call ('next')."),
7812 set_schedlock_func
, /* traps on target vector */
7813 show_scheduler_mode
,
7814 &setlist
, &showlist
);
7816 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7817 Set mode for resuming threads of all processes."), _("\
7818 Show mode for resuming threads of all processes."), _("\
7819 When on, execution commands (such as 'continue' or 'next') resume all\n\
7820 threads of all processes. When off (which is the default), execution\n\
7821 commands only resume the threads of the current process. The set of\n\
7822 threads that are resumed is further refined by the scheduler-locking\n\
7823 mode (see help set scheduler-locking)."),
7825 show_schedule_multiple
,
7826 &setlist
, &showlist
);
7828 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7829 Set mode of the step operation."), _("\
7830 Show mode of the step operation."), _("\
7831 When set, doing a step over a function without debug line information\n\
7832 will stop at the first instruction of that function. Otherwise, the\n\
7833 function is skipped and the step command stops at a different source line."),
7835 show_step_stop_if_no_debug
,
7836 &setlist
, &showlist
);
7838 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
7839 &can_use_displaced_stepping
, _("\
7840 Set debugger's willingness to use displaced stepping."), _("\
7841 Show debugger's willingness to use displaced stepping."), _("\
7842 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7843 supported by the target architecture. If off, gdb will not use displaced\n\
7844 stepping to step over breakpoints, even if such is supported by the target\n\
7845 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7846 if the target architecture supports it and non-stop mode is active, but will not\n\
7847 use it in all-stop mode (see help set non-stop)."),
7849 show_can_use_displaced_stepping
,
7850 &setlist
, &showlist
);
7852 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7853 &exec_direction
, _("Set direction of execution.\n\
7854 Options are 'forward' or 'reverse'."),
7855 _("Show direction of execution (forward/reverse)."),
7856 _("Tells gdb whether to execute forward or backward."),
7857 set_exec_direction_func
, show_exec_direction_func
,
7858 &setlist
, &showlist
);
7860 /* Set/show detach-on-fork: user-settable mode. */
7862 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7863 Set whether gdb will detach the child of a fork."), _("\
7864 Show whether gdb will detach the child of a fork."), _("\
7865 Tells gdb whether to detach the child of a fork."),
7866 NULL
, NULL
, &setlist
, &showlist
);
7868 /* Set/show disable address space randomization mode. */
7870 add_setshow_boolean_cmd ("disable-randomization", class_support
,
7871 &disable_randomization
, _("\
7872 Set disabling of debuggee's virtual address space randomization."), _("\
7873 Show disabling of debuggee's virtual address space randomization."), _("\
7874 When this mode is on (which is the default), randomization of the virtual\n\
7875 address space is disabled. Standalone programs run with the randomization\n\
7876 enabled by default on some platforms."),
7877 &set_disable_randomization
,
7878 &show_disable_randomization
,
7879 &setlist
, &showlist
);
7881 /* ptid initializations */
7882 inferior_ptid
= null_ptid
;
7883 target_last_wait_ptid
= minus_one_ptid
;
7885 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7886 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7887 observer_attach_thread_exit (infrun_thread_thread_exit
);
7888 observer_attach_inferior_exit (infrun_inferior_exit
);
7890 /* Explicitly create without lookup, since that tries to create a
7891 value with a void typed value, and when we get here, gdbarch
7892 isn't initialized yet. At this point, we're quite sure there
7893 isn't another convenience variable of the same name. */
7894 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
7896 add_setshow_boolean_cmd ("observer", no_class
,
7897 &observer_mode_1
, _("\
7898 Set whether gdb controls the inferior in observer mode."), _("\
7899 Show whether gdb controls the inferior in observer mode."), _("\
7900 In observer mode, GDB can get data from the inferior, but not\n\
7901 affect its execution. Registers and memory may not be changed,\n\
7902 breakpoints may not be set, and the program cannot be interrupted\n\