1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
5 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
6 2008, 2009 Free Software Foundation, Inc.
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "gdb_string.h"
29 #include "exceptions.h"
30 #include "breakpoint.h"
34 #include "cli/cli-script.h"
36 #include "gdbthread.h"
48 #include "gdb_assert.h"
49 #include "mi/mi-common.h"
50 #include "event-top.h"
52 #include "inline-frame.h"
55 /* Prototypes for local functions */
57 static void signals_info (char *, int);
59 static void handle_command (char *, int);
61 static void sig_print_info (enum target_signal
);
63 static void sig_print_header (void);
65 static void resume_cleanups (void *);
67 static int hook_stop_stub (void *);
69 static int restore_selected_frame (void *);
71 static void build_infrun (void);
73 static int follow_fork (void);
75 static void set_schedlock_func (char *args
, int from_tty
,
76 struct cmd_list_element
*c
);
78 static int currently_stepping (struct thread_info
*tp
);
80 static int currently_stepping_or_nexting_callback (struct thread_info
*tp
,
83 static void xdb_handle_command (char *args
, int from_tty
);
85 static int prepare_to_proceed (int);
87 void _initialize_infrun (void);
89 void nullify_last_target_wait_ptid (void);
91 /* When set, stop the 'step' command if we enter a function which has
92 no line number information. The normal behavior is that we step
93 over such function. */
94 int step_stop_if_no_debug
= 0;
96 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
97 struct cmd_list_element
*c
, const char *value
)
99 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
102 /* In asynchronous mode, but simulating synchronous execution. */
104 int sync_execution
= 0;
106 /* wait_for_inferior and normal_stop use this to notify the user
107 when the inferior stopped in a different thread than it had been
110 static ptid_t previous_inferior_ptid
;
112 /* Default behavior is to detach newly forked processes (legacy). */
115 int debug_displaced
= 0;
117 show_debug_displaced (struct ui_file
*file
, int from_tty
,
118 struct cmd_list_element
*c
, const char *value
)
120 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
123 static int debug_infrun
= 0;
125 show_debug_infrun (struct ui_file
*file
, int from_tty
,
126 struct cmd_list_element
*c
, const char *value
)
128 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
131 /* If the program uses ELF-style shared libraries, then calls to
132 functions in shared libraries go through stubs, which live in a
133 table called the PLT (Procedure Linkage Table). The first time the
134 function is called, the stub sends control to the dynamic linker,
135 which looks up the function's real address, patches the stub so
136 that future calls will go directly to the function, and then passes
137 control to the function.
139 If we are stepping at the source level, we don't want to see any of
140 this --- we just want to skip over the stub and the dynamic linker.
141 The simple approach is to single-step until control leaves the
144 However, on some systems (e.g., Red Hat's 5.2 distribution) the
145 dynamic linker calls functions in the shared C library, so you
146 can't tell from the PC alone whether the dynamic linker is still
147 running. In this case, we use a step-resume breakpoint to get us
148 past the dynamic linker, as if we were using "next" to step over a
151 in_solib_dynsym_resolve_code() says whether we're in the dynamic
152 linker code or not. Normally, this means we single-step. However,
153 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
154 address where we can place a step-resume breakpoint to get past the
155 linker's symbol resolution function.
157 in_solib_dynsym_resolve_code() can generally be implemented in a
158 pretty portable way, by comparing the PC against the address ranges
159 of the dynamic linker's sections.
161 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
162 it depends on internal details of the dynamic linker. It's usually
163 not too hard to figure out where to put a breakpoint, but it
164 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
165 sanity checking. If it can't figure things out, returning zero and
166 getting the (possibly confusing) stepping behavior is better than
167 signalling an error, which will obscure the change in the
170 /* This function returns TRUE if pc is the address of an instruction
171 that lies within the dynamic linker (such as the event hook, or the
174 This function must be used only when a dynamic linker event has
175 been caught, and the inferior is being stepped out of the hook, or
176 undefined results are guaranteed. */
178 #ifndef SOLIB_IN_DYNAMIC_LINKER
179 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
183 /* Convert the #defines into values. This is temporary until wfi control
184 flow is completely sorted out. */
186 #ifndef CANNOT_STEP_HW_WATCHPOINTS
187 #define CANNOT_STEP_HW_WATCHPOINTS 0
189 #undef CANNOT_STEP_HW_WATCHPOINTS
190 #define CANNOT_STEP_HW_WATCHPOINTS 1
193 /* Tables of how to react to signals; the user sets them. */
195 static unsigned char *signal_stop
;
196 static unsigned char *signal_print
;
197 static unsigned char *signal_program
;
199 #define SET_SIGS(nsigs,sigs,flags) \
201 int signum = (nsigs); \
202 while (signum-- > 0) \
203 if ((sigs)[signum]) \
204 (flags)[signum] = 1; \
207 #define UNSET_SIGS(nsigs,sigs,flags) \
209 int signum = (nsigs); \
210 while (signum-- > 0) \
211 if ((sigs)[signum]) \
212 (flags)[signum] = 0; \
215 /* Value to pass to target_resume() to cause all threads to resume */
217 #define RESUME_ALL minus_one_ptid
219 /* Command list pointer for the "stop" placeholder. */
221 static struct cmd_list_element
*stop_command
;
223 /* Function inferior was in as of last step command. */
225 static struct symbol
*step_start_function
;
227 /* Nonzero if we want to give control to the user when we're notified
228 of shared library events by the dynamic linker. */
229 static int stop_on_solib_events
;
231 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
232 struct cmd_list_element
*c
, const char *value
)
234 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
238 /* Nonzero means expecting a trace trap
239 and should stop the inferior and return silently when it happens. */
243 /* Save register contents here when executing a "finish" command or are
244 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
245 Thus this contains the return value from the called function (assuming
246 values are returned in a register). */
248 struct regcache
*stop_registers
;
250 /* Nonzero after stop if current stack frame should be printed. */
252 static int stop_print_frame
;
254 /* This is a cached copy of the pid/waitstatus of the last event
255 returned by target_wait()/deprecated_target_wait_hook(). This
256 information is returned by get_last_target_status(). */
257 static ptid_t target_last_wait_ptid
;
258 static struct target_waitstatus target_last_waitstatus
;
260 static void context_switch (ptid_t ptid
);
262 void init_thread_stepping_state (struct thread_info
*tss
);
264 void init_infwait_state (void);
266 static const char follow_fork_mode_child
[] = "child";
267 static const char follow_fork_mode_parent
[] = "parent";
269 static const char *follow_fork_mode_kind_names
[] = {
270 follow_fork_mode_child
,
271 follow_fork_mode_parent
,
275 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
277 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
278 struct cmd_list_element
*c
, const char *value
)
280 fprintf_filtered (file
, _("\
281 Debugger response to a program call of fork or vfork is \"%s\".\n"),
286 /* Tell the target to follow the fork we're stopped at. Returns true
287 if the inferior should be resumed; false, if the target for some
288 reason decided it's best not to resume. */
293 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
294 int should_resume
= 1;
295 struct thread_info
*tp
;
297 /* Copy user stepping state to the new inferior thread. FIXME: the
298 followed fork child thread should have a copy of most of the
299 parent thread structure's run control related fields, not just these.
300 Initialized to avoid "may be used uninitialized" warnings from gcc. */
301 struct breakpoint
*step_resume_breakpoint
= NULL
;
302 CORE_ADDR step_range_start
= 0;
303 CORE_ADDR step_range_end
= 0;
304 struct frame_id step_frame_id
= { 0 };
309 struct target_waitstatus wait_status
;
311 /* Get the last target status returned by target_wait(). */
312 get_last_target_status (&wait_ptid
, &wait_status
);
314 /* If not stopped at a fork event, then there's nothing else to
316 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
317 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
320 /* Check if we switched over from WAIT_PTID, since the event was
322 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
323 && !ptid_equal (inferior_ptid
, wait_ptid
))
325 /* We did. Switch back to WAIT_PTID thread, to tell the
326 target to follow it (in either direction). We'll
327 afterwards refuse to resume, and inform the user what
329 switch_to_thread (wait_ptid
);
334 tp
= inferior_thread ();
336 /* If there were any forks/vforks that were caught and are now to be
337 followed, then do so now. */
338 switch (tp
->pending_follow
.kind
)
340 case TARGET_WAITKIND_FORKED
:
341 case TARGET_WAITKIND_VFORKED
:
343 ptid_t parent
, child
;
345 /* If the user did a next/step, etc, over a fork call,
346 preserve the stepping state in the fork child. */
347 if (follow_child
&& should_resume
)
349 step_resume_breakpoint
350 = clone_momentary_breakpoint (tp
->step_resume_breakpoint
);
351 step_range_start
= tp
->step_range_start
;
352 step_range_end
= tp
->step_range_end
;
353 step_frame_id
= tp
->step_frame_id
;
355 /* For now, delete the parent's sr breakpoint, otherwise,
356 parent/child sr breakpoints are considered duplicates,
357 and the child version will not be installed. Remove
358 this when the breakpoints module becomes aware of
359 inferiors and address spaces. */
360 delete_step_resume_breakpoint (tp
);
361 tp
->step_range_start
= 0;
362 tp
->step_range_end
= 0;
363 tp
->step_frame_id
= null_frame_id
;
366 parent
= inferior_ptid
;
367 child
= tp
->pending_follow
.value
.related_pid
;
369 /* Tell the target to do whatever is necessary to follow
370 either parent or child. */
371 if (target_follow_fork (follow_child
))
373 /* Target refused to follow, or there's some other reason
374 we shouldn't resume. */
379 /* This pending follow fork event is now handled, one way
380 or another. The previous selected thread may be gone
381 from the lists by now, but if it is still around, need
382 to clear the pending follow request. */
383 tp
= find_thread_ptid (parent
);
385 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
387 /* This makes sure we don't try to apply the "Switched
388 over from WAIT_PID" logic above. */
389 nullify_last_target_wait_ptid ();
391 /* If we followed the child, switch to it... */
394 switch_to_thread (child
);
396 /* ... and preserve the stepping state, in case the
397 user was stepping over the fork call. */
400 tp
= inferior_thread ();
401 tp
->step_resume_breakpoint
= step_resume_breakpoint
;
402 tp
->step_range_start
= step_range_start
;
403 tp
->step_range_end
= step_range_end
;
404 tp
->step_frame_id
= step_frame_id
;
408 /* If we get here, it was because we're trying to
409 resume from a fork catchpoint, but, the user
410 has switched threads away from the thread that
411 forked. In that case, the resume command
412 issued is most likely not applicable to the
413 child, so just warn, and refuse to resume. */
415 Not resuming: switched threads before following fork child.\n"));
418 /* Reset breakpoints in the child as appropriate. */
419 follow_inferior_reset_breakpoints ();
422 switch_to_thread (parent
);
426 case TARGET_WAITKIND_SPURIOUS
:
427 /* Nothing to follow. */
430 internal_error (__FILE__
, __LINE__
,
431 "Unexpected pending_follow.kind %d\n",
432 tp
->pending_follow
.kind
);
436 return should_resume
;
440 follow_inferior_reset_breakpoints (void)
442 struct thread_info
*tp
= inferior_thread ();
444 /* Was there a step_resume breakpoint? (There was if the user
445 did a "next" at the fork() call.) If so, explicitly reset its
448 step_resumes are a form of bp that are made to be per-thread.
449 Since we created the step_resume bp when the parent process
450 was being debugged, and now are switching to the child process,
451 from the breakpoint package's viewpoint, that's a switch of
452 "threads". We must update the bp's notion of which thread
453 it is for, or it'll be ignored when it triggers. */
455 if (tp
->step_resume_breakpoint
)
456 breakpoint_re_set_thread (tp
->step_resume_breakpoint
);
458 /* Reinsert all breakpoints in the child. The user may have set
459 breakpoints after catching the fork, in which case those
460 were never set in the child, but only in the parent. This makes
461 sure the inserted breakpoints match the breakpoint list. */
463 breakpoint_re_set ();
464 insert_breakpoints ();
467 /* The child has exited or execed: resume threads of the parent the
468 user wanted to be executing. */
471 proceed_after_vfork_done (struct thread_info
*thread
,
474 int pid
= * (int *) arg
;
476 if (ptid_get_pid (thread
->ptid
) == pid
477 && is_running (thread
->ptid
)
478 && !is_executing (thread
->ptid
)
479 && !thread
->stop_requested
480 && thread
->stop_signal
== TARGET_SIGNAL_0
)
483 fprintf_unfiltered (gdb_stdlog
,
484 "infrun: resuming vfork parent thread %s\n",
485 target_pid_to_str (thread
->ptid
));
487 switch_to_thread (thread
->ptid
);
488 clear_proceed_status ();
489 proceed ((CORE_ADDR
) -1, TARGET_SIGNAL_DEFAULT
, 0);
495 /* Called whenever we notice an exec or exit event, to handle
496 detaching or resuming a vfork parent. */
499 handle_vfork_child_exec_or_exit (int exec
)
501 struct inferior
*inf
= current_inferior ();
503 if (inf
->vfork_parent
)
505 int resume_parent
= -1;
507 /* This exec or exit marks the end of the shared memory region
508 between the parent and the child. If the user wanted to
509 detach from the parent, now is the time. */
511 if (inf
->vfork_parent
->pending_detach
)
513 struct thread_info
*tp
;
514 struct cleanup
*old_chain
;
515 struct program_space
*pspace
;
516 struct address_space
*aspace
;
518 /* follow-fork child, detach-on-fork on */
520 old_chain
= make_cleanup_restore_current_thread ();
522 /* We're letting loose of the parent. */
523 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
524 switch_to_thread (tp
->ptid
);
526 /* We're about to detach from the parent, which implicitly
527 removes breakpoints from its address space. There's a
528 catch here: we want to reuse the spaces for the child,
529 but, parent/child are still sharing the pspace at this
530 point, although the exec in reality makes the kernel give
531 the child a fresh set of new pages. The problem here is
532 that the breakpoints module being unaware of this, would
533 likely chose the child process to write to the parent
534 address space. Swapping the child temporarily away from
535 the spaces has the desired effect. Yes, this is "sort
538 pspace
= inf
->pspace
;
539 aspace
= inf
->aspace
;
543 if (debug_infrun
|| info_verbose
)
545 target_terminal_ours ();
548 fprintf_filtered (gdb_stdlog
,
549 "Detaching vfork parent process %d after child exec.\n",
550 inf
->vfork_parent
->pid
);
552 fprintf_filtered (gdb_stdlog
,
553 "Detaching vfork parent process %d after child exit.\n",
554 inf
->vfork_parent
->pid
);
557 target_detach (NULL
, 0);
560 inf
->pspace
= pspace
;
561 inf
->aspace
= aspace
;
563 do_cleanups (old_chain
);
567 /* We're staying attached to the parent, so, really give the
568 child a new address space. */
569 inf
->pspace
= add_program_space (maybe_new_address_space ());
570 inf
->aspace
= inf
->pspace
->aspace
;
572 set_current_program_space (inf
->pspace
);
574 resume_parent
= inf
->vfork_parent
->pid
;
576 /* Break the bonds. */
577 inf
->vfork_parent
->vfork_child
= NULL
;
581 struct cleanup
*old_chain
;
582 struct program_space
*pspace
;
584 /* If this is a vfork child exiting, then the pspace and
585 aspaces were shared with the parent. Since we're
586 reporting the process exit, we'll be mourning all that is
587 found in the address space, and switching to null_ptid,
588 preparing to start a new inferior. But, since we don't
589 want to clobber the parent's address/program spaces, we
590 go ahead and create a new one for this exiting
593 /* Switch to null_ptid, so that clone_program_space doesn't want
594 to read the selected frame of a dead process. */
595 old_chain
= save_inferior_ptid ();
596 inferior_ptid
= null_ptid
;
598 /* This inferior is dead, so avoid giving the breakpoints
599 module the option to write through to it (cloning a
600 program space resets breakpoints). */
603 pspace
= add_program_space (maybe_new_address_space ());
604 set_current_program_space (pspace
);
606 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
607 inf
->pspace
= pspace
;
608 inf
->aspace
= pspace
->aspace
;
610 /* Put back inferior_ptid. We'll continue mourning this
612 do_cleanups (old_chain
);
614 resume_parent
= inf
->vfork_parent
->pid
;
615 /* Break the bonds. */
616 inf
->vfork_parent
->vfork_child
= NULL
;
619 inf
->vfork_parent
= NULL
;
621 gdb_assert (current_program_space
== inf
->pspace
);
623 if (non_stop
&& resume_parent
!= -1)
625 /* If the user wanted the parent to be running, let it go
627 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
630 fprintf_unfiltered (gdb_stdlog
, "infrun: resuming vfork parent process %d\n",
633 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
635 do_cleanups (old_chain
);
640 /* Enum strings for "set|show displaced-stepping". */
642 static const char follow_exec_mode_new
[] = "new";
643 static const char follow_exec_mode_same
[] = "same";
644 static const char *follow_exec_mode_names
[] =
646 follow_exec_mode_new
,
647 follow_exec_mode_same
,
651 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
653 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
654 struct cmd_list_element
*c
, const char *value
)
656 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
659 /* EXECD_PATHNAME is assumed to be non-NULL. */
662 follow_exec (ptid_t pid
, char *execd_pathname
)
664 struct target_ops
*tgt
;
665 struct thread_info
*th
= inferior_thread ();
666 struct inferior
*inf
= current_inferior ();
668 /* This is an exec event that we actually wish to pay attention to.
669 Refresh our symbol table to the newly exec'd program, remove any
672 If there are breakpoints, they aren't really inserted now,
673 since the exec() transformed our inferior into a fresh set
676 We want to preserve symbolic breakpoints on the list, since
677 we have hopes that they can be reset after the new a.out's
678 symbol table is read.
680 However, any "raw" breakpoints must be removed from the list
681 (e.g., the solib bp's), since their address is probably invalid
684 And, we DON'T want to call delete_breakpoints() here, since
685 that may write the bp's "shadow contents" (the instruction
686 value that was overwritten witha TRAP instruction). Since
687 we now have a new a.out, those shadow contents aren't valid. */
689 mark_breakpoints_out ();
691 update_breakpoints_after_exec ();
693 /* If there was one, it's gone now. We cannot truly step-to-next
694 statement through an exec(). */
695 th
->step_resume_breakpoint
= NULL
;
696 th
->step_range_start
= 0;
697 th
->step_range_end
= 0;
699 /* The target reports the exec event to the main thread, even if
700 some other thread does the exec, and even if the main thread was
701 already stopped --- if debugging in non-stop mode, it's possible
702 the user had the main thread held stopped in the previous image
703 --- release it now. This is the same behavior as step-over-exec
704 with scheduler-locking on in all-stop mode. */
705 th
->stop_requested
= 0;
707 /* What is this a.out's name? */
708 printf_unfiltered (_("%s is executing new program: %s\n"),
709 target_pid_to_str (inferior_ptid
),
712 /* We've followed the inferior through an exec. Therefore, the
713 inferior has essentially been killed & reborn. */
715 gdb_flush (gdb_stdout
);
717 breakpoint_init_inferior (inf_execd
);
719 if (gdb_sysroot
&& *gdb_sysroot
)
721 char *name
= alloca (strlen (gdb_sysroot
)
722 + strlen (execd_pathname
)
724 strcpy (name
, gdb_sysroot
);
725 strcat (name
, execd_pathname
);
726 execd_pathname
= name
;
729 /* Reset the shared library package. This ensures that we get a
730 shlib event when the child reaches "_start", at which point the
731 dld will have had a chance to initialize the child. */
732 /* Also, loading a symbol file below may trigger symbol lookups, and
733 we don't want those to be satisfied by the libraries of the
734 previous incarnation of this process. */
735 no_shared_libraries (NULL
, 0);
737 if (follow_exec_mode_string
== follow_exec_mode_new
)
739 struct program_space
*pspace
;
740 struct inferior
*new_inf
;
742 /* The user wants to keep the old inferior and program spaces
743 around. Create a new fresh one, and switch to it. */
745 inf
= add_inferior (current_inferior ()->pid
);
746 pspace
= add_program_space (maybe_new_address_space ());
747 inf
->pspace
= pspace
;
748 inf
->aspace
= pspace
->aspace
;
750 exit_inferior_num_silent (current_inferior ()->num
);
752 set_current_inferior (inf
);
753 set_current_program_space (pspace
);
756 gdb_assert (current_program_space
== inf
->pspace
);
758 /* That a.out is now the one to use. */
759 exec_file_attach (execd_pathname
, 0);
761 /* Load the main file's symbols. */
762 symbol_file_add_main (execd_pathname
, 0);
764 #ifdef SOLIB_CREATE_INFERIOR_HOOK
765 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
767 solib_create_inferior_hook ();
770 jit_inferior_created_hook ();
772 /* Reinsert all breakpoints. (Those which were symbolic have
773 been reset to the proper address in the new a.out, thanks
774 to symbol_file_command...) */
775 insert_breakpoints ();
777 /* The next resume of this inferior should bring it to the shlib
778 startup breakpoints. (If the user had also set bp's on
779 "main" from the old (parent) process, then they'll auto-
780 matically get reset there in the new process.) */
783 /* Non-zero if we just simulating a single-step. This is needed
784 because we cannot remove the breakpoints in the inferior process
785 until after the `wait' in `wait_for_inferior'. */
786 static int singlestep_breakpoints_inserted_p
= 0;
788 /* The thread we inserted single-step breakpoints for. */
789 static ptid_t singlestep_ptid
;
791 /* PC when we started this single-step. */
792 static CORE_ADDR singlestep_pc
;
794 /* If another thread hit the singlestep breakpoint, we save the original
795 thread here so that we can resume single-stepping it later. */
796 static ptid_t saved_singlestep_ptid
;
797 static int stepping_past_singlestep_breakpoint
;
799 /* If not equal to null_ptid, this means that after stepping over breakpoint
800 is finished, we need to switch to deferred_step_ptid, and step it.
802 The use case is when one thread has hit a breakpoint, and then the user
803 has switched to another thread and issued 'step'. We need to step over
804 breakpoint in the thread which hit the breakpoint, but then continue
805 stepping the thread user has selected. */
806 static ptid_t deferred_step_ptid
;
808 /* Displaced stepping. */
810 /* In non-stop debugging mode, we must take special care to manage
811 breakpoints properly; in particular, the traditional strategy for
812 stepping a thread past a breakpoint it has hit is unsuitable.
813 'Displaced stepping' is a tactic for stepping one thread past a
814 breakpoint it has hit while ensuring that other threads running
815 concurrently will hit the breakpoint as they should.
817 The traditional way to step a thread T off a breakpoint in a
818 multi-threaded program in all-stop mode is as follows:
820 a0) Initially, all threads are stopped, and breakpoints are not
822 a1) We single-step T, leaving breakpoints uninserted.
823 a2) We insert breakpoints, and resume all threads.
825 In non-stop debugging, however, this strategy is unsuitable: we
826 don't want to have to stop all threads in the system in order to
827 continue or step T past a breakpoint. Instead, we use displaced
830 n0) Initially, T is stopped, other threads are running, and
831 breakpoints are inserted.
832 n1) We copy the instruction "under" the breakpoint to a separate
833 location, outside the main code stream, making any adjustments
834 to the instruction, register, and memory state as directed by
836 n2) We single-step T over the instruction at its new location.
837 n3) We adjust the resulting register and memory state as directed
838 by T's architecture. This includes resetting T's PC to point
839 back into the main instruction stream.
842 This approach depends on the following gdbarch methods:
844 - gdbarch_max_insn_length and gdbarch_displaced_step_location
845 indicate where to copy the instruction, and how much space must
846 be reserved there. We use these in step n1.
848 - gdbarch_displaced_step_copy_insn copies a instruction to a new
849 address, and makes any necessary adjustments to the instruction,
850 register contents, and memory. We use this in step n1.
852 - gdbarch_displaced_step_fixup adjusts registers and memory after
853 we have successfuly single-stepped the instruction, to yield the
854 same effect the instruction would have had if we had executed it
855 at its original address. We use this in step n3.
857 - gdbarch_displaced_step_free_closure provides cleanup.
859 The gdbarch_displaced_step_copy_insn and
860 gdbarch_displaced_step_fixup functions must be written so that
861 copying an instruction with gdbarch_displaced_step_copy_insn,
862 single-stepping across the copied instruction, and then applying
863 gdbarch_displaced_insn_fixup should have the same effects on the
864 thread's memory and registers as stepping the instruction in place
865 would have. Exactly which responsibilities fall to the copy and
866 which fall to the fixup is up to the author of those functions.
868 See the comments in gdbarch.sh for details.
870 Note that displaced stepping and software single-step cannot
871 currently be used in combination, although with some care I think
872 they could be made to. Software single-step works by placing
873 breakpoints on all possible subsequent instructions; if the
874 displaced instruction is a PC-relative jump, those breakpoints
875 could fall in very strange places --- on pages that aren't
876 executable, or at addresses that are not proper instruction
877 boundaries. (We do generally let other threads run while we wait
878 to hit the software single-step breakpoint, and they might
879 encounter such a corrupted instruction.) One way to work around
880 this would be to have gdbarch_displaced_step_copy_insn fully
881 simulate the effect of PC-relative instructions (and return NULL)
882 on architectures that use software single-stepping.
884 In non-stop mode, we can have independent and simultaneous step
885 requests, so more than one thread may need to simultaneously step
886 over a breakpoint. The current implementation assumes there is
887 only one scratch space per process. In this case, we have to
888 serialize access to the scratch space. If thread A wants to step
889 over a breakpoint, but we are currently waiting for some other
890 thread to complete a displaced step, we leave thread A stopped and
891 place it in the displaced_step_request_queue. Whenever a displaced
892 step finishes, we pick the next thread in the queue and start a new
893 displaced step operation on it. See displaced_step_prepare and
894 displaced_step_fixup for details. */
896 /* If this is not null_ptid, this is the thread carrying out a
897 displaced single-step. This thread's state will require fixing up
898 once it has completed its step. */
899 static ptid_t displaced_step_ptid
;
901 struct displaced_step_request
904 struct displaced_step_request
*next
;
907 /* A queue of pending displaced stepping requests. */
908 struct displaced_step_request
*displaced_step_request_queue
;
910 /* The architecture the thread had when we stepped it. */
911 static struct gdbarch
*displaced_step_gdbarch
;
913 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
914 for post-step cleanup. */
915 static struct displaced_step_closure
*displaced_step_closure
;
917 /* The address of the original instruction, and the copy we made. */
918 static CORE_ADDR displaced_step_original
, displaced_step_copy
;
920 /* Saved contents of copy area. */
921 static gdb_byte
*displaced_step_saved_copy
;
923 /* Enum strings for "set|show displaced-stepping". */
925 static const char can_use_displaced_stepping_auto
[] = "auto";
926 static const char can_use_displaced_stepping_on
[] = "on";
927 static const char can_use_displaced_stepping_off
[] = "off";
928 static const char *can_use_displaced_stepping_enum
[] =
930 can_use_displaced_stepping_auto
,
931 can_use_displaced_stepping_on
,
932 can_use_displaced_stepping_off
,
936 /* If ON, and the architecture supports it, GDB will use displaced
937 stepping to step over breakpoints. If OFF, or if the architecture
938 doesn't support it, GDB will instead use the traditional
939 hold-and-step approach. If AUTO (which is the default), GDB will
940 decide which technique to use to step over breakpoints depending on
941 which of all-stop or non-stop mode is active --- displaced stepping
942 in non-stop mode; hold-and-step in all-stop mode. */
944 static const char *can_use_displaced_stepping
=
945 can_use_displaced_stepping_auto
;
948 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
949 struct cmd_list_element
*c
,
952 if (can_use_displaced_stepping
== can_use_displaced_stepping_auto
)
953 fprintf_filtered (file
, _("\
954 Debugger's willingness to use displaced stepping to step over \
955 breakpoints is %s (currently %s).\n"),
956 value
, non_stop
? "on" : "off");
958 fprintf_filtered (file
, _("\
959 Debugger's willingness to use displaced stepping to step over \
960 breakpoints is %s.\n"), value
);
963 /* Return non-zero if displaced stepping can/should be used to step
967 use_displaced_stepping (struct gdbarch
*gdbarch
)
969 return (((can_use_displaced_stepping
== can_use_displaced_stepping_auto
971 || can_use_displaced_stepping
== can_use_displaced_stepping_on
)
972 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
976 /* Clean out any stray displaced stepping state. */
978 displaced_step_clear (void)
980 /* Indicate that there is no cleanup pending. */
981 displaced_step_ptid
= null_ptid
;
983 if (displaced_step_closure
)
985 gdbarch_displaced_step_free_closure (displaced_step_gdbarch
,
986 displaced_step_closure
);
987 displaced_step_closure
= NULL
;
992 displaced_step_clear_cleanup (void *ignore
)
994 displaced_step_clear ();
997 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
999 displaced_step_dump_bytes (struct ui_file
*file
,
1000 const gdb_byte
*buf
,
1005 for (i
= 0; i
< len
; i
++)
1006 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1007 fputs_unfiltered ("\n", file
);
1010 /* Prepare to single-step, using displaced stepping.
1012 Note that we cannot use displaced stepping when we have a signal to
1013 deliver. If we have a signal to deliver and an instruction to step
1014 over, then after the step, there will be no indication from the
1015 target whether the thread entered a signal handler or ignored the
1016 signal and stepped over the instruction successfully --- both cases
1017 result in a simple SIGTRAP. In the first case we mustn't do a
1018 fixup, and in the second case we must --- but we can't tell which.
1019 Comments in the code for 'random signals' in handle_inferior_event
1020 explain how we handle this case instead.
1022 Returns 1 if preparing was successful -- this thread is going to be
1023 stepped now; or 0 if displaced stepping this thread got queued. */
1025 displaced_step_prepare (ptid_t ptid
)
1027 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1028 struct regcache
*regcache
= get_thread_regcache (ptid
);
1029 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1030 CORE_ADDR original
, copy
;
1032 struct displaced_step_closure
*closure
;
1034 /* We should never reach this function if the architecture does not
1035 support displaced stepping. */
1036 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1038 /* For the first cut, we're displaced stepping one thread at a
1041 if (!ptid_equal (displaced_step_ptid
, null_ptid
))
1043 /* Already waiting for a displaced step to finish. Defer this
1044 request and place in queue. */
1045 struct displaced_step_request
*req
, *new_req
;
1047 if (debug_displaced
)
1048 fprintf_unfiltered (gdb_stdlog
,
1049 "displaced: defering step of %s\n",
1050 target_pid_to_str (ptid
));
1052 new_req
= xmalloc (sizeof (*new_req
));
1053 new_req
->ptid
= ptid
;
1054 new_req
->next
= NULL
;
1056 if (displaced_step_request_queue
)
1058 for (req
= displaced_step_request_queue
;
1062 req
->next
= new_req
;
1065 displaced_step_request_queue
= new_req
;
1071 if (debug_displaced
)
1072 fprintf_unfiltered (gdb_stdlog
,
1073 "displaced: stepping %s now\n",
1074 target_pid_to_str (ptid
));
1077 displaced_step_clear ();
1079 old_cleanups
= save_inferior_ptid ();
1080 inferior_ptid
= ptid
;
1082 original
= regcache_read_pc (regcache
);
1084 copy
= gdbarch_displaced_step_location (gdbarch
);
1085 len
= gdbarch_max_insn_length (gdbarch
);
1087 /* Save the original contents of the copy area. */
1088 displaced_step_saved_copy
= xmalloc (len
);
1089 ignore_cleanups
= make_cleanup (free_current_contents
,
1090 &displaced_step_saved_copy
);
1091 read_memory (copy
, displaced_step_saved_copy
, len
);
1092 if (debug_displaced
)
1094 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1095 paddress (gdbarch
, copy
));
1096 displaced_step_dump_bytes (gdb_stdlog
, displaced_step_saved_copy
, len
);
1099 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1100 original
, copy
, regcache
);
1102 /* We don't support the fully-simulated case at present. */
1103 gdb_assert (closure
);
1105 /* Save the information we need to fix things up if the step
1107 displaced_step_ptid
= ptid
;
1108 displaced_step_gdbarch
= gdbarch
;
1109 displaced_step_closure
= closure
;
1110 displaced_step_original
= original
;
1111 displaced_step_copy
= copy
;
1113 make_cleanup (displaced_step_clear_cleanup
, 0);
1115 /* Resume execution at the copy. */
1116 regcache_write_pc (regcache
, copy
);
1118 discard_cleanups (ignore_cleanups
);
1120 do_cleanups (old_cleanups
);
1122 if (debug_displaced
)
1123 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1124 paddress (gdbarch
, copy
));
1130 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
, const gdb_byte
*myaddr
, int len
)
1132 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1133 inferior_ptid
= ptid
;
1134 write_memory (memaddr
, myaddr
, len
);
1135 do_cleanups (ptid_cleanup
);
1139 displaced_step_fixup (ptid_t event_ptid
, enum target_signal signal
)
1141 struct cleanup
*old_cleanups
;
1143 /* Was this event for the pid we displaced? */
1144 if (ptid_equal (displaced_step_ptid
, null_ptid
)
1145 || ! ptid_equal (displaced_step_ptid
, event_ptid
))
1148 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, 0);
1150 /* Restore the contents of the copy area. */
1152 ULONGEST len
= gdbarch_max_insn_length (displaced_step_gdbarch
);
1153 write_memory_ptid (displaced_step_ptid
, displaced_step_copy
,
1154 displaced_step_saved_copy
, len
);
1155 if (debug_displaced
)
1156 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s\n",
1157 paddress (displaced_step_gdbarch
,
1158 displaced_step_copy
));
1161 /* Did the instruction complete successfully? */
1162 if (signal
== TARGET_SIGNAL_TRAP
)
1164 /* Fix up the resulting state. */
1165 gdbarch_displaced_step_fixup (displaced_step_gdbarch
,
1166 displaced_step_closure
,
1167 displaced_step_original
,
1168 displaced_step_copy
,
1169 get_thread_regcache (displaced_step_ptid
));
1173 /* Since the instruction didn't complete, all we can do is
1175 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1176 CORE_ADDR pc
= regcache_read_pc (regcache
);
1177 pc
= displaced_step_original
+ (pc
- displaced_step_copy
);
1178 regcache_write_pc (regcache
, pc
);
1181 do_cleanups (old_cleanups
);
1183 displaced_step_ptid
= null_ptid
;
1185 /* Are there any pending displaced stepping requests? If so, run
1187 while (displaced_step_request_queue
)
1189 struct displaced_step_request
*head
;
1191 struct regcache
*regcache
;
1192 struct gdbarch
*gdbarch
;
1193 CORE_ADDR actual_pc
;
1194 struct address_space
*aspace
;
1196 head
= displaced_step_request_queue
;
1198 displaced_step_request_queue
= head
->next
;
1201 context_switch (ptid
);
1203 regcache
= get_thread_regcache (ptid
);
1204 actual_pc
= regcache_read_pc (regcache
);
1205 aspace
= get_regcache_aspace (regcache
);
1207 if (breakpoint_here_p (aspace
, actual_pc
))
1209 if (debug_displaced
)
1210 fprintf_unfiltered (gdb_stdlog
,
1211 "displaced: stepping queued %s now\n",
1212 target_pid_to_str (ptid
));
1214 displaced_step_prepare (ptid
);
1216 gdbarch
= get_regcache_arch (regcache
);
1218 if (debug_displaced
)
1220 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1223 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1224 paddress (gdbarch
, actual_pc
));
1225 read_memory (actual_pc
, buf
, sizeof (buf
));
1226 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1229 if (gdbarch_displaced_step_hw_singlestep
1230 (gdbarch
, displaced_step_closure
))
1231 target_resume (ptid
, 1, TARGET_SIGNAL_0
);
1233 target_resume (ptid
, 0, TARGET_SIGNAL_0
);
1235 /* Done, we're stepping a thread. */
1241 struct thread_info
*tp
= inferior_thread ();
1243 /* The breakpoint we were sitting under has since been
1245 tp
->trap_expected
= 0;
1247 /* Go back to what we were trying to do. */
1248 step
= currently_stepping (tp
);
1250 if (debug_displaced
)
1251 fprintf_unfiltered (gdb_stdlog
, "breakpoint is gone %s: step(%d)\n",
1252 target_pid_to_str (tp
->ptid
), step
);
1254 target_resume (ptid
, step
, TARGET_SIGNAL_0
);
1255 tp
->stop_signal
= TARGET_SIGNAL_0
;
1257 /* This request was discarded. See if there's any other
1258 thread waiting for its turn. */
1263 /* Update global variables holding ptids to hold NEW_PTID if they were
1264 holding OLD_PTID. */
1266 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1268 struct displaced_step_request
*it
;
1270 if (ptid_equal (inferior_ptid
, old_ptid
))
1271 inferior_ptid
= new_ptid
;
1273 if (ptid_equal (singlestep_ptid
, old_ptid
))
1274 singlestep_ptid
= new_ptid
;
1276 if (ptid_equal (displaced_step_ptid
, old_ptid
))
1277 displaced_step_ptid
= new_ptid
;
1279 if (ptid_equal (deferred_step_ptid
, old_ptid
))
1280 deferred_step_ptid
= new_ptid
;
1282 for (it
= displaced_step_request_queue
; it
; it
= it
->next
)
1283 if (ptid_equal (it
->ptid
, old_ptid
))
1284 it
->ptid
= new_ptid
;
1290 /* Things to clean up if we QUIT out of resume (). */
1292 resume_cleanups (void *ignore
)
1297 static const char schedlock_off
[] = "off";
1298 static const char schedlock_on
[] = "on";
1299 static const char schedlock_step
[] = "step";
1300 static const char *scheduler_enums
[] = {
1306 static const char *scheduler_mode
= schedlock_off
;
1308 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1309 struct cmd_list_element
*c
, const char *value
)
1311 fprintf_filtered (file
, _("\
1312 Mode for locking scheduler during execution is \"%s\".\n"),
1317 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1319 if (!target_can_lock_scheduler
)
1321 scheduler_mode
= schedlock_off
;
1322 error (_("Target '%s' cannot support this command."), target_shortname
);
1326 /* True if execution commands resume all threads of all processes by
1327 default; otherwise, resume only threads of the current inferior
1329 int sched_multi
= 0;
1331 /* Try to setup for software single stepping over the specified location.
1332 Return 1 if target_resume() should use hardware single step.
1334 GDBARCH the current gdbarch.
1335 PC the location to step over. */
1338 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1342 if (gdbarch_software_single_step_p (gdbarch
)
1343 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1346 /* Do not pull these breakpoints until after a `wait' in
1347 `wait_for_inferior' */
1348 singlestep_breakpoints_inserted_p
= 1;
1349 singlestep_ptid
= inferior_ptid
;
1355 /* Resume the inferior, but allow a QUIT. This is useful if the user
1356 wants to interrupt some lengthy single-stepping operation
1357 (for child processes, the SIGINT goes to the inferior, and so
1358 we get a SIGINT random_signal, but for remote debugging and perhaps
1359 other targets, that's not true).
1361 STEP nonzero if we should step (zero to continue instead).
1362 SIG is the signal to give the inferior (zero for none). */
1364 resume (int step
, enum target_signal sig
)
1366 int should_resume
= 1;
1367 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
1368 struct regcache
*regcache
= get_current_regcache ();
1369 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1370 struct thread_info
*tp
= inferior_thread ();
1371 CORE_ADDR pc
= regcache_read_pc (regcache
);
1372 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1377 fprintf_unfiltered (gdb_stdlog
,
1378 "infrun: resume (step=%d, signal=%d), "
1379 "trap_expected=%d\n",
1380 step
, sig
, tp
->trap_expected
);
1382 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
1383 over an instruction that causes a page fault without triggering
1384 a hardware watchpoint. The kernel properly notices that it shouldn't
1385 stop, because the hardware watchpoint is not triggered, but it forgets
1386 the step request and continues the program normally.
1387 Work around the problem by removing hardware watchpoints if a step is
1388 requested, GDB will check for a hardware watchpoint trigger after the
1390 if (CANNOT_STEP_HW_WATCHPOINTS
&& step
)
1391 remove_hw_watchpoints ();
1394 /* Normally, by the time we reach `resume', the breakpoints are either
1395 removed or inserted, as appropriate. The exception is if we're sitting
1396 at a permanent breakpoint; we need to step over it, but permanent
1397 breakpoints can't be removed. So we have to test for it here. */
1398 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
1400 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
1401 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
1404 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1405 how to step past a permanent breakpoint on this architecture. Try using\n\
1406 a command like `return' or `jump' to continue execution."));
1409 /* If enabled, step over breakpoints by executing a copy of the
1410 instruction at a different address.
1412 We can't use displaced stepping when we have a signal to deliver;
1413 the comments for displaced_step_prepare explain why. The
1414 comments in the handle_inferior event for dealing with 'random
1415 signals' explain what we do instead. */
1416 if (use_displaced_stepping (gdbarch
)
1417 && (tp
->trap_expected
1418 || (step
&& gdbarch_software_single_step_p (gdbarch
)))
1419 && sig
== TARGET_SIGNAL_0
)
1421 if (!displaced_step_prepare (inferior_ptid
))
1423 /* Got placed in displaced stepping queue. Will be resumed
1424 later when all the currently queued displaced stepping
1425 requests finish. The thread is not executing at this point,
1426 and the call to set_executing will be made later. But we
1427 need to call set_running here, since from frontend point of view,
1428 the thread is running. */
1429 set_running (inferior_ptid
, 1);
1430 discard_cleanups (old_cleanups
);
1434 step
= gdbarch_displaced_step_hw_singlestep
1435 (gdbarch
, displaced_step_closure
);
1438 /* Do we need to do it the hard way, w/temp breakpoints? */
1440 step
= maybe_software_singlestep (gdbarch
, pc
);
1446 /* If STEP is set, it's a request to use hardware stepping
1447 facilities. But in that case, we should never
1448 use singlestep breakpoint. */
1449 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1451 /* Decide the set of threads to ask the target to resume. Start
1452 by assuming everything will be resumed, than narrow the set
1453 by applying increasingly restricting conditions. */
1455 /* By default, resume all threads of all processes. */
1456 resume_ptid
= RESUME_ALL
;
1458 /* Maybe resume only all threads of the current process. */
1459 if (!sched_multi
&& target_supports_multi_process ())
1461 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1464 /* Maybe resume a single thread after all. */
1465 if (singlestep_breakpoints_inserted_p
1466 && stepping_past_singlestep_breakpoint
)
1468 /* The situation here is as follows. In thread T1 we wanted to
1469 single-step. Lacking hardware single-stepping we've
1470 set breakpoint at the PC of the next instruction -- call it
1471 P. After resuming, we've hit that breakpoint in thread T2.
1472 Now we've removed original breakpoint, inserted breakpoint
1473 at P+1, and try to step to advance T2 past breakpoint.
1474 We need to step only T2, as if T1 is allowed to freely run,
1475 it can run past P, and if other threads are allowed to run,
1476 they can hit breakpoint at P+1, and nested hits of single-step
1477 breakpoints is not something we'd want -- that's complicated
1478 to support, and has no value. */
1479 resume_ptid
= inferior_ptid
;
1481 else if ((step
|| singlestep_breakpoints_inserted_p
)
1482 && tp
->trap_expected
)
1484 /* We're allowing a thread to run past a breakpoint it has
1485 hit, by single-stepping the thread with the breakpoint
1486 removed. In which case, we need to single-step only this
1487 thread, and keep others stopped, as they can miss this
1488 breakpoint if allowed to run.
1490 The current code actually removes all breakpoints when
1491 doing this, not just the one being stepped over, so if we
1492 let other threads run, we can actually miss any
1493 breakpoint, not just the one at PC. */
1494 resume_ptid
= inferior_ptid
;
1498 /* With non-stop mode on, threads are always handled
1500 resume_ptid
= inferior_ptid
;
1502 else if ((scheduler_mode
== schedlock_on
)
1503 || (scheduler_mode
== schedlock_step
1504 && (step
|| singlestep_breakpoints_inserted_p
)))
1506 /* User-settable 'scheduler' mode requires solo thread resume. */
1507 resume_ptid
= inferior_ptid
;
1510 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1512 /* Most targets can step a breakpoint instruction, thus
1513 executing it normally. But if this one cannot, just
1514 continue and we will hit it anyway. */
1515 if (step
&& breakpoint_inserted_here_p (aspace
, pc
))
1520 && use_displaced_stepping (gdbarch
)
1521 && tp
->trap_expected
)
1523 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1524 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
1525 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1528 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1529 paddress (resume_gdbarch
, actual_pc
));
1530 read_memory (actual_pc
, buf
, sizeof (buf
));
1531 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1534 /* Install inferior's terminal modes. */
1535 target_terminal_inferior ();
1537 /* Avoid confusing the next resume, if the next stop/resume
1538 happens to apply to another thread. */
1539 tp
->stop_signal
= TARGET_SIGNAL_0
;
1541 target_resume (resume_ptid
, step
, sig
);
1544 discard_cleanups (old_cleanups
);
1549 /* Clear out all variables saying what to do when inferior is continued.
1550 First do this, then set the ones you want, then call `proceed'. */
1553 clear_proceed_status_thread (struct thread_info
*tp
)
1556 fprintf_unfiltered (gdb_stdlog
,
1557 "infrun: clear_proceed_status_thread (%s)\n",
1558 target_pid_to_str (tp
->ptid
));
1560 tp
->trap_expected
= 0;
1561 tp
->step_range_start
= 0;
1562 tp
->step_range_end
= 0;
1563 tp
->step_frame_id
= null_frame_id
;
1564 tp
->step_stack_frame_id
= null_frame_id
;
1565 tp
->step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1566 tp
->stop_requested
= 0;
1570 tp
->proceed_to_finish
= 0;
1572 /* Discard any remaining commands or status from previous stop. */
1573 bpstat_clear (&tp
->stop_bpstat
);
1577 clear_proceed_status_callback (struct thread_info
*tp
, void *data
)
1579 if (is_exited (tp
->ptid
))
1582 clear_proceed_status_thread (tp
);
1587 clear_proceed_status (void)
1591 /* In all-stop mode, delete the per-thread status of all
1592 threads, even if inferior_ptid is null_ptid, there may be
1593 threads on the list. E.g., we may be launching a new
1594 process, while selecting the executable. */
1595 iterate_over_threads (clear_proceed_status_callback
, NULL
);
1598 if (!ptid_equal (inferior_ptid
, null_ptid
))
1600 struct inferior
*inferior
;
1604 /* If in non-stop mode, only delete the per-thread status of
1605 the current thread. */
1606 clear_proceed_status_thread (inferior_thread ());
1609 inferior
= current_inferior ();
1610 inferior
->stop_soon
= NO_STOP_QUIETLY
;
1613 stop_after_trap
= 0;
1615 observer_notify_about_to_proceed ();
1619 regcache_xfree (stop_registers
);
1620 stop_registers
= NULL
;
1624 /* Check the current thread against the thread that reported the most recent
1625 event. If a step-over is required return TRUE and set the current thread
1626 to the old thread. Otherwise return FALSE.
1628 This should be suitable for any targets that support threads. */
1631 prepare_to_proceed (int step
)
1634 struct target_waitstatus wait_status
;
1635 int schedlock_enabled
;
1637 /* With non-stop mode on, threads are always handled individually. */
1638 gdb_assert (! non_stop
);
1640 /* Get the last target status returned by target_wait(). */
1641 get_last_target_status (&wait_ptid
, &wait_status
);
1643 /* Make sure we were stopped at a breakpoint. */
1644 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
1645 || wait_status
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1650 schedlock_enabled
= (scheduler_mode
== schedlock_on
1651 || (scheduler_mode
== schedlock_step
1654 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
1655 if (schedlock_enabled
)
1658 /* Don't switch over if we're about to resume some other process
1659 other than WAIT_PTID's, and schedule-multiple is off. */
1661 && ptid_get_pid (wait_ptid
) != ptid_get_pid (inferior_ptid
))
1664 /* Switched over from WAIT_PID. */
1665 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
1666 && !ptid_equal (inferior_ptid
, wait_ptid
))
1668 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
1670 if (breakpoint_here_p (get_regcache_aspace (regcache
),
1671 regcache_read_pc (regcache
)))
1673 /* If stepping, remember current thread to switch back to. */
1675 deferred_step_ptid
= inferior_ptid
;
1677 /* Switch back to WAIT_PID thread. */
1678 switch_to_thread (wait_ptid
);
1680 /* We return 1 to indicate that there is a breakpoint here,
1681 so we need to step over it before continuing to avoid
1682 hitting it straight away. */
1690 /* Basic routine for continuing the program in various fashions.
1692 ADDR is the address to resume at, or -1 for resume where stopped.
1693 SIGGNAL is the signal to give it, or 0 for none,
1694 or -1 for act according to how it stopped.
1695 STEP is nonzero if should trap after one instruction.
1696 -1 means return after that and print nothing.
1697 You should probably set various step_... variables
1698 before calling here, if you are stepping.
1700 You should call clear_proceed_status before calling proceed. */
1703 proceed (CORE_ADDR addr
, enum target_signal siggnal
, int step
)
1705 struct regcache
*regcache
;
1706 struct gdbarch
*gdbarch
;
1707 struct thread_info
*tp
;
1709 struct address_space
*aspace
;
1712 /* If we're stopped at a fork/vfork, follow the branch set by the
1713 "set follow-fork-mode" command; otherwise, we'll just proceed
1714 resuming the current thread. */
1715 if (!follow_fork ())
1717 /* The target for some reason decided not to resume. */
1722 regcache
= get_current_regcache ();
1723 gdbarch
= get_regcache_arch (regcache
);
1724 aspace
= get_regcache_aspace (regcache
);
1725 pc
= regcache_read_pc (regcache
);
1728 step_start_function
= find_pc_function (pc
);
1730 stop_after_trap
= 1;
1732 if (addr
== (CORE_ADDR
) -1)
1734 if (pc
== stop_pc
&& breakpoint_here_p (aspace
, pc
)
1735 && execution_direction
!= EXEC_REVERSE
)
1736 /* There is a breakpoint at the address we will resume at,
1737 step one instruction before inserting breakpoints so that
1738 we do not stop right away (and report a second hit at this
1741 Note, we don't do this in reverse, because we won't
1742 actually be executing the breakpoint insn anyway.
1743 We'll be (un-)executing the previous instruction. */
1746 else if (gdbarch_single_step_through_delay_p (gdbarch
)
1747 && gdbarch_single_step_through_delay (gdbarch
,
1748 get_current_frame ()))
1749 /* We stepped onto an instruction that needs to be stepped
1750 again before re-inserting the breakpoint, do so. */
1755 regcache_write_pc (regcache
, addr
);
1759 fprintf_unfiltered (gdb_stdlog
,
1760 "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
1761 paddress (gdbarch
, addr
), siggnal
, step
);
1764 /* In non-stop, each thread is handled individually. The context
1765 must already be set to the right thread here. */
1769 /* In a multi-threaded task we may select another thread and
1770 then continue or step.
1772 But if the old thread was stopped at a breakpoint, it will
1773 immediately cause another breakpoint stop without any
1774 execution (i.e. it will report a breakpoint hit incorrectly).
1775 So we must step over it first.
1777 prepare_to_proceed checks the current thread against the
1778 thread that reported the most recent event. If a step-over
1779 is required it returns TRUE and sets the current thread to
1781 if (prepare_to_proceed (step
))
1785 /* prepare_to_proceed may change the current thread. */
1786 tp
= inferior_thread ();
1790 tp
->trap_expected
= 1;
1791 /* If displaced stepping is enabled, we can step over the
1792 breakpoint without hitting it, so leave all breakpoints
1793 inserted. Otherwise we need to disable all breakpoints, step
1794 one instruction, and then re-add them when that step is
1796 if (!use_displaced_stepping (gdbarch
))
1797 remove_breakpoints ();
1800 /* We can insert breakpoints if we're not trying to step over one,
1801 or if we are stepping over one but we're using displaced stepping
1803 if (! tp
->trap_expected
|| use_displaced_stepping (gdbarch
))
1804 insert_breakpoints ();
1808 /* Pass the last stop signal to the thread we're resuming,
1809 irrespective of whether the current thread is the thread that
1810 got the last event or not. This was historically GDB's
1811 behaviour before keeping a stop_signal per thread. */
1813 struct thread_info
*last_thread
;
1815 struct target_waitstatus last_status
;
1817 get_last_target_status (&last_ptid
, &last_status
);
1818 if (!ptid_equal (inferior_ptid
, last_ptid
)
1819 && !ptid_equal (last_ptid
, null_ptid
)
1820 && !ptid_equal (last_ptid
, minus_one_ptid
))
1822 last_thread
= find_thread_ptid (last_ptid
);
1825 tp
->stop_signal
= last_thread
->stop_signal
;
1826 last_thread
->stop_signal
= TARGET_SIGNAL_0
;
1831 if (siggnal
!= TARGET_SIGNAL_DEFAULT
)
1832 tp
->stop_signal
= siggnal
;
1833 /* If this signal should not be seen by program,
1834 give it zero. Used for debugging signals. */
1835 else if (!signal_program
[tp
->stop_signal
])
1836 tp
->stop_signal
= TARGET_SIGNAL_0
;
1838 annotate_starting ();
1840 /* Make sure that output from GDB appears before output from the
1842 gdb_flush (gdb_stdout
);
1844 /* Refresh prev_pc value just prior to resuming. This used to be
1845 done in stop_stepping, however, setting prev_pc there did not handle
1846 scenarios such as inferior function calls or returning from
1847 a function via the return command. In those cases, the prev_pc
1848 value was not set properly for subsequent commands. The prev_pc value
1849 is used to initialize the starting line number in the ecs. With an
1850 invalid value, the gdb next command ends up stopping at the position
1851 represented by the next line table entry past our start position.
1852 On platforms that generate one line table entry per line, this
1853 is not a problem. However, on the ia64, the compiler generates
1854 extraneous line table entries that do not increase the line number.
1855 When we issue the gdb next command on the ia64 after an inferior call
1856 or a return command, we often end up a few instructions forward, still
1857 within the original line we started.
1859 An attempt was made to have init_execution_control_state () refresh
1860 the prev_pc value before calculating the line number. This approach
1861 did not work because on platforms that use ptrace, the pc register
1862 cannot be read unless the inferior is stopped. At that point, we
1863 are not guaranteed the inferior is stopped and so the regcache_read_pc ()
1864 call can fail. Setting the prev_pc value here ensures the value is
1865 updated correctly when the inferior is stopped. */
1866 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
1868 /* Fill in with reasonable starting values. */
1869 init_thread_stepping_state (tp
);
1871 /* Reset to normal state. */
1872 init_infwait_state ();
1874 /* Resume inferior. */
1875 resume (oneproc
|| step
|| bpstat_should_step (), tp
->stop_signal
);
1877 /* Wait for it to stop (if not standalone)
1878 and in any case decode why it stopped, and act accordingly. */
1879 /* Do this only if we are not using the event loop, or if the target
1880 does not support asynchronous execution. */
1881 if (!target_can_async_p ())
1883 wait_for_inferior (0);
1889 /* Start remote-debugging of a machine over a serial link. */
1892 start_remote (int from_tty
)
1894 struct inferior
*inferior
;
1895 init_wait_for_inferior ();
1897 inferior
= current_inferior ();
1898 inferior
->stop_soon
= STOP_QUIETLY_REMOTE
;
1900 /* Always go on waiting for the target, regardless of the mode. */
1901 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1902 indicate to wait_for_inferior that a target should timeout if
1903 nothing is returned (instead of just blocking). Because of this,
1904 targets expecting an immediate response need to, internally, set
1905 things up so that the target_wait() is forced to eventually
1907 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1908 differentiate to its caller what the state of the target is after
1909 the initial open has been performed. Here we're assuming that
1910 the target has stopped. It should be possible to eventually have
1911 target_open() return to the caller an indication that the target
1912 is currently running and GDB state should be set to the same as
1913 for an async run. */
1914 wait_for_inferior (0);
1916 /* Now that the inferior has stopped, do any bookkeeping like
1917 loading shared libraries. We want to do this before normal_stop,
1918 so that the displayed frame is up to date. */
1919 post_create_inferior (¤t_target
, from_tty
);
1924 /* Initialize static vars when a new inferior begins. */
1927 init_wait_for_inferior (void)
1929 /* These are meaningless until the first time through wait_for_inferior. */
1931 breakpoint_init_inferior (inf_starting
);
1933 clear_proceed_status ();
1935 stepping_past_singlestep_breakpoint
= 0;
1936 deferred_step_ptid
= null_ptid
;
1938 target_last_wait_ptid
= minus_one_ptid
;
1940 previous_inferior_ptid
= null_ptid
;
1941 init_infwait_state ();
1943 displaced_step_clear ();
1945 /* Discard any skipped inlined frames. */
1946 clear_inline_frame_state (minus_one_ptid
);
1950 /* This enum encodes possible reasons for doing a target_wait, so that
1951 wfi can call target_wait in one place. (Ultimately the call will be
1952 moved out of the infinite loop entirely.) */
1956 infwait_normal_state
,
1957 infwait_thread_hop_state
,
1958 infwait_step_watch_state
,
1959 infwait_nonstep_watch_state
1962 /* Why did the inferior stop? Used to print the appropriate messages
1963 to the interface from within handle_inferior_event(). */
1964 enum inferior_stop_reason
1966 /* Step, next, nexti, stepi finished. */
1968 /* Inferior terminated by signal. */
1970 /* Inferior exited. */
1972 /* Inferior received signal, and user asked to be notified. */
1974 /* Reverse execution -- target ran out of history info. */
1978 /* The PTID we'll do a target_wait on.*/
1981 /* Current inferior wait state. */
1982 enum infwait_states infwait_state
;
1984 /* Data to be passed around while handling an event. This data is
1985 discarded between events. */
1986 struct execution_control_state
1989 /* The thread that got the event, if this was a thread event; NULL
1991 struct thread_info
*event_thread
;
1993 struct target_waitstatus ws
;
1995 CORE_ADDR stop_func_start
;
1996 CORE_ADDR stop_func_end
;
1997 char *stop_func_name
;
1998 int new_thread_event
;
2002 static void init_execution_control_state (struct execution_control_state
*ecs
);
2004 static void handle_inferior_event (struct execution_control_state
*ecs
);
2006 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2007 struct execution_control_state
*ecs
);
2008 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2009 struct execution_control_state
*ecs
);
2010 static void insert_step_resume_breakpoint_at_frame (struct frame_info
*step_frame
);
2011 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
2012 static void insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
2013 struct symtab_and_line sr_sal
,
2014 struct frame_id sr_id
);
2015 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
2017 static void stop_stepping (struct execution_control_state
*ecs
);
2018 static void prepare_to_wait (struct execution_control_state
*ecs
);
2019 static void keep_going (struct execution_control_state
*ecs
);
2020 static void print_stop_reason (enum inferior_stop_reason stop_reason
,
2023 /* Callback for iterate over threads. If the thread is stopped, but
2024 the user/frontend doesn't know about that yet, go through
2025 normal_stop, as if the thread had just stopped now. ARG points at
2026 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2027 ptid_is_pid(PTID) is true, applies to all threads of the process
2028 pointed at by PTID. Otherwise, apply only to the thread pointed by
2032 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2034 ptid_t ptid
= * (ptid_t
*) arg
;
2036 if ((ptid_equal (info
->ptid
, ptid
)
2037 || ptid_equal (minus_one_ptid
, ptid
)
2038 || (ptid_is_pid (ptid
)
2039 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2040 && is_running (info
->ptid
)
2041 && !is_executing (info
->ptid
))
2043 struct cleanup
*old_chain
;
2044 struct execution_control_state ecss
;
2045 struct execution_control_state
*ecs
= &ecss
;
2047 memset (ecs
, 0, sizeof (*ecs
));
2049 old_chain
= make_cleanup_restore_current_thread ();
2051 switch_to_thread (info
->ptid
);
2053 /* Go through handle_inferior_event/normal_stop, so we always
2054 have consistent output as if the stop event had been
2056 ecs
->ptid
= info
->ptid
;
2057 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2058 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2059 ecs
->ws
.value
.sig
= TARGET_SIGNAL_0
;
2061 handle_inferior_event (ecs
);
2063 if (!ecs
->wait_some_more
)
2065 struct thread_info
*tp
;
2069 /* Finish off the continuations. The continations
2070 themselves are responsible for realising the thread
2071 didn't finish what it was supposed to do. */
2072 tp
= inferior_thread ();
2073 do_all_intermediate_continuations_thread (tp
);
2074 do_all_continuations_thread (tp
);
2077 do_cleanups (old_chain
);
2083 /* This function is attached as a "thread_stop_requested" observer.
2084 Cleanup local state that assumed the PTID was to be resumed, and
2085 report the stop to the frontend. */
2088 infrun_thread_stop_requested (ptid_t ptid
)
2090 struct displaced_step_request
*it
, *next
, *prev
= NULL
;
2092 /* PTID was requested to stop. Remove it from the displaced
2093 stepping queue, so we don't try to resume it automatically. */
2094 for (it
= displaced_step_request_queue
; it
; it
= next
)
2098 if (ptid_equal (it
->ptid
, ptid
)
2099 || ptid_equal (minus_one_ptid
, ptid
)
2100 || (ptid_is_pid (ptid
)
2101 && ptid_get_pid (ptid
) == ptid_get_pid (it
->ptid
)))
2103 if (displaced_step_request_queue
== it
)
2104 displaced_step_request_queue
= it
->next
;
2106 prev
->next
= it
->next
;
2114 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2118 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2120 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2121 nullify_last_target_wait_ptid ();
2124 /* Callback for iterate_over_threads. */
2127 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
2129 if (is_exited (info
->ptid
))
2132 delete_step_resume_breakpoint (info
);
2136 /* In all-stop, delete the step resume breakpoint of any thread that
2137 had one. In non-stop, delete the step resume breakpoint of the
2138 thread that just stopped. */
2141 delete_step_thread_step_resume_breakpoint (void)
2143 if (!target_has_execution
2144 || ptid_equal (inferior_ptid
, null_ptid
))
2145 /* If the inferior has exited, we have already deleted the step
2146 resume breakpoints out of GDB's lists. */
2151 /* If in non-stop mode, only delete the step-resume or
2152 longjmp-resume breakpoint of the thread that just stopped
2154 struct thread_info
*tp
= inferior_thread ();
2155 delete_step_resume_breakpoint (tp
);
2158 /* In all-stop mode, delete all step-resume and longjmp-resume
2159 breakpoints of any thread that had them. */
2160 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
2163 /* A cleanup wrapper. */
2166 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
2168 delete_step_thread_step_resume_breakpoint ();
2171 /* Pretty print the results of target_wait, for debugging purposes. */
2174 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2175 const struct target_waitstatus
*ws
)
2177 char *status_string
= target_waitstatus_to_string (ws
);
2178 struct ui_file
*tmp_stream
= mem_fileopen ();
2181 /* The text is split over several lines because it was getting too long.
2182 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2183 output as a unit; we want only one timestamp printed if debug_timestamp
2186 fprintf_unfiltered (tmp_stream
,
2187 "infrun: target_wait (%d", PIDGET (waiton_ptid
));
2188 if (PIDGET (waiton_ptid
) != -1)
2189 fprintf_unfiltered (tmp_stream
,
2190 " [%s]", target_pid_to_str (waiton_ptid
));
2191 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2192 fprintf_unfiltered (tmp_stream
,
2193 "infrun: %d [%s],\n",
2194 PIDGET (result_ptid
), target_pid_to_str (result_ptid
));
2195 fprintf_unfiltered (tmp_stream
,
2199 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2201 /* This uses %s in part to handle %'s in the text, but also to avoid
2202 a gcc error: the format attribute requires a string literal. */
2203 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2205 xfree (status_string
);
2207 ui_file_delete (tmp_stream
);
2210 /* Wait for control to return from inferior to debugger.
2212 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
2213 as if they were SIGTRAP signals. This can be useful during
2214 the startup sequence on some targets such as HP/UX, where
2215 we receive an EXEC event instead of the expected SIGTRAP.
2217 If inferior gets a signal, we may decide to start it up again
2218 instead of returning. That is why there is a loop in this function.
2219 When this function actually returns it means the inferior
2220 should be left stopped and GDB should read more commands. */
2223 wait_for_inferior (int treat_exec_as_sigtrap
)
2225 struct cleanup
*old_cleanups
;
2226 struct execution_control_state ecss
;
2227 struct execution_control_state
*ecs
;
2231 (gdb_stdlog
, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
2232 treat_exec_as_sigtrap
);
2235 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
2238 memset (ecs
, 0, sizeof (*ecs
));
2240 /* We'll update this if & when we switch to a new thread. */
2241 previous_inferior_ptid
= inferior_ptid
;
2245 struct cleanup
*old_chain
;
2247 /* We have to invalidate the registers BEFORE calling target_wait
2248 because they can be loaded from the target while in target_wait.
2249 This makes remote debugging a bit more efficient for those
2250 targets that provide critical registers as part of their normal
2251 status mechanism. */
2253 overlay_cache_invalid
= 1;
2254 registers_changed ();
2256 if (deprecated_target_wait_hook
)
2257 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2259 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2262 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2264 if (treat_exec_as_sigtrap
&& ecs
->ws
.kind
== TARGET_WAITKIND_EXECD
)
2266 xfree (ecs
->ws
.value
.execd_pathname
);
2267 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2268 ecs
->ws
.value
.sig
= TARGET_SIGNAL_TRAP
;
2271 /* If an error happens while handling the event, propagate GDB's
2272 knowledge of the executing state to the frontend/user running
2274 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2276 if (ecs
->ws
.kind
== TARGET_WAITKIND_SYSCALL_ENTRY
2277 || ecs
->ws
.kind
== TARGET_WAITKIND_SYSCALL_RETURN
)
2278 ecs
->ws
.value
.syscall_number
= UNKNOWN_SYSCALL
;
2280 /* Now figure out what to do with the result of the result. */
2281 handle_inferior_event (ecs
);
2283 /* No error, don't finish the state yet. */
2284 discard_cleanups (old_chain
);
2286 if (!ecs
->wait_some_more
)
2290 do_cleanups (old_cleanups
);
2293 /* Asynchronous version of wait_for_inferior. It is called by the
2294 event loop whenever a change of state is detected on the file
2295 descriptor corresponding to the target. It can be called more than
2296 once to complete a single execution command. In such cases we need
2297 to keep the state in a global variable ECSS. If it is the last time
2298 that this function is called for a single execution command, then
2299 report to the user that the inferior has stopped, and do the
2300 necessary cleanups. */
2303 fetch_inferior_event (void *client_data
)
2305 struct execution_control_state ecss
;
2306 struct execution_control_state
*ecs
= &ecss
;
2307 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2308 struct cleanup
*ts_old_chain
;
2309 int was_sync
= sync_execution
;
2311 memset (ecs
, 0, sizeof (*ecs
));
2313 /* We'll update this if & when we switch to a new thread. */
2314 previous_inferior_ptid
= inferior_ptid
;
2317 /* In non-stop mode, the user/frontend should not notice a thread
2318 switch due to internal events. Make sure we reverse to the
2319 user selected thread and frame after handling the event and
2320 running any breakpoint commands. */
2321 make_cleanup_restore_current_thread ();
2323 /* We have to invalidate the registers BEFORE calling target_wait
2324 because they can be loaded from the target while in target_wait.
2325 This makes remote debugging a bit more efficient for those
2326 targets that provide critical registers as part of their normal
2327 status mechanism. */
2329 overlay_cache_invalid
= 1;
2330 registers_changed ();
2332 if (deprecated_target_wait_hook
)
2334 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2336 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2339 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2342 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
2343 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2344 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2345 /* In non-stop mode, each thread is handled individually. Switch
2346 early, so the global state is set correctly for this
2348 context_switch (ecs
->ptid
);
2350 /* If an error happens while handling the event, propagate GDB's
2351 knowledge of the executing state to the frontend/user running
2354 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2356 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2358 /* Now figure out what to do with the result of the result. */
2359 handle_inferior_event (ecs
);
2361 if (!ecs
->wait_some_more
)
2363 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2365 delete_step_thread_step_resume_breakpoint ();
2367 /* We may not find an inferior if this was a process exit. */
2368 if (inf
== NULL
|| inf
->stop_soon
== NO_STOP_QUIETLY
)
2371 if (target_has_execution
2372 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2373 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2374 && ecs
->event_thread
->step_multi
2375 && ecs
->event_thread
->stop_step
)
2376 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2378 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2381 /* No error, don't finish the thread states yet. */
2382 discard_cleanups (ts_old_chain
);
2384 /* Revert thread and frame. */
2385 do_cleanups (old_chain
);
2387 /* If the inferior was in sync execution mode, and now isn't,
2388 restore the prompt. */
2389 if (was_sync
&& !sync_execution
)
2390 display_gdb_prompt (0);
2393 /* Record the frame and location we're currently stepping through. */
2395 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2397 struct thread_info
*tp
= inferior_thread ();
2399 tp
->step_frame_id
= get_frame_id (frame
);
2400 tp
->step_stack_frame_id
= get_stack_frame_id (frame
);
2402 tp
->current_symtab
= sal
.symtab
;
2403 tp
->current_line
= sal
.line
;
2406 /* Prepare an execution control state for looping through a
2407 wait_for_inferior-type loop. */
2410 init_execution_control_state (struct execution_control_state
*ecs
)
2412 ecs
->random_signal
= 0;
2415 /* Clear context switchable stepping state. */
2418 init_thread_stepping_state (struct thread_info
*tss
)
2420 tss
->stepping_over_breakpoint
= 0;
2421 tss
->step_after_step_resume_breakpoint
= 0;
2422 tss
->stepping_through_solib_after_catch
= 0;
2423 tss
->stepping_through_solib_catchpoints
= NULL
;
2426 /* Return the cached copy of the last pid/waitstatus returned by
2427 target_wait()/deprecated_target_wait_hook(). The data is actually
2428 cached by handle_inferior_event(), which gets called immediately
2429 after target_wait()/deprecated_target_wait_hook(). */
2432 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2434 *ptidp
= target_last_wait_ptid
;
2435 *status
= target_last_waitstatus
;
2439 nullify_last_target_wait_ptid (void)
2441 target_last_wait_ptid
= minus_one_ptid
;
2444 /* Switch thread contexts. */
2447 context_switch (ptid_t ptid
)
2451 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2452 target_pid_to_str (inferior_ptid
));
2453 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2454 target_pid_to_str (ptid
));
2457 switch_to_thread (ptid
);
2461 adjust_pc_after_break (struct execution_control_state
*ecs
)
2463 struct regcache
*regcache
;
2464 struct gdbarch
*gdbarch
;
2465 struct address_space
*aspace
;
2466 CORE_ADDR breakpoint_pc
;
2468 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2469 we aren't, just return.
2471 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2472 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2473 implemented by software breakpoints should be handled through the normal
2476 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2477 different signals (SIGILL or SIGEMT for instance), but it is less
2478 clear where the PC is pointing afterwards. It may not match
2479 gdbarch_decr_pc_after_break. I don't know any specific target that
2480 generates these signals at breakpoints (the code has been in GDB since at
2481 least 1992) so I can not guess how to handle them here.
2483 In earlier versions of GDB, a target with
2484 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2485 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2486 target with both of these set in GDB history, and it seems unlikely to be
2487 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2489 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2492 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
2495 /* In reverse execution, when a breakpoint is hit, the instruction
2496 under it has already been de-executed. The reported PC always
2497 points at the breakpoint address, so adjusting it further would
2498 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2501 B1 0x08000000 : INSN1
2502 B2 0x08000001 : INSN2
2504 PC -> 0x08000003 : INSN4
2506 Say you're stopped at 0x08000003 as above. Reverse continuing
2507 from that point should hit B2 as below. Reading the PC when the
2508 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2509 been de-executed already.
2511 B1 0x08000000 : INSN1
2512 B2 PC -> 0x08000001 : INSN2
2516 We can't apply the same logic as for forward execution, because
2517 we would wrongly adjust the PC to 0x08000000, since there's a
2518 breakpoint at PC - 1. We'd then report a hit on B1, although
2519 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2521 if (execution_direction
== EXEC_REVERSE
)
2524 /* If this target does not decrement the PC after breakpoints, then
2525 we have nothing to do. */
2526 regcache
= get_thread_regcache (ecs
->ptid
);
2527 gdbarch
= get_regcache_arch (regcache
);
2528 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
2531 aspace
= get_regcache_aspace (regcache
);
2533 /* Find the location where (if we've hit a breakpoint) the
2534 breakpoint would be. */
2535 breakpoint_pc
= regcache_read_pc (regcache
)
2536 - gdbarch_decr_pc_after_break (gdbarch
);
2538 /* Check whether there actually is a software breakpoint inserted at
2541 If in non-stop mode, a race condition is possible where we've
2542 removed a breakpoint, but stop events for that breakpoint were
2543 already queued and arrive later. To suppress those spurious
2544 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
2545 and retire them after a number of stop events are reported. */
2546 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
2547 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
2549 struct cleanup
*old_cleanups
= NULL
;
2551 old_cleanups
= record_gdb_operation_disable_set ();
2553 /* When using hardware single-step, a SIGTRAP is reported for both
2554 a completed single-step and a software breakpoint. Need to
2555 differentiate between the two, as the latter needs adjusting
2556 but the former does not.
2558 The SIGTRAP can be due to a completed hardware single-step only if
2559 - we didn't insert software single-step breakpoints
2560 - the thread to be examined is still the current thread
2561 - this thread is currently being stepped
2563 If any of these events did not occur, we must have stopped due
2564 to hitting a software breakpoint, and have to back up to the
2567 As a special case, we could have hardware single-stepped a
2568 software breakpoint. In this case (prev_pc == breakpoint_pc),
2569 we also need to back up to the breakpoint address. */
2571 if (singlestep_breakpoints_inserted_p
2572 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
2573 || !currently_stepping (ecs
->event_thread
)
2574 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
2575 regcache_write_pc (regcache
, breakpoint_pc
);
2578 do_cleanups (old_cleanups
);
2583 init_infwait_state (void)
2585 waiton_ptid
= pid_to_ptid (-1);
2586 infwait_state
= infwait_normal_state
;
2590 error_is_running (void)
2593 Cannot execute this command while the selected thread is running."));
2597 ensure_not_running (void)
2599 if (is_running (inferior_ptid
))
2600 error_is_running ();
2604 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
2606 for (frame
= get_prev_frame (frame
);
2608 frame
= get_prev_frame (frame
))
2610 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
2612 if (get_frame_type (frame
) != INLINE_FRAME
)
2619 /* Auxiliary function that handles syscall entry/return events.
2620 It returns 1 if the inferior should keep going (and GDB
2621 should ignore the event), or 0 if the event deserves to be
2625 handle_syscall_event (struct execution_control_state
*ecs
)
2627 struct regcache
*regcache
;
2628 struct gdbarch
*gdbarch
;
2631 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2632 context_switch (ecs
->ptid
);
2634 regcache
= get_thread_regcache (ecs
->ptid
);
2635 gdbarch
= get_regcache_arch (regcache
);
2636 syscall_number
= gdbarch_get_syscall_number (gdbarch
, ecs
->ptid
);
2637 stop_pc
= regcache_read_pc (regcache
);
2639 target_last_waitstatus
.value
.syscall_number
= syscall_number
;
2641 if (catch_syscall_enabled () > 0
2642 && catching_syscall_number (syscall_number
) > 0)
2645 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
2648 ecs
->event_thread
->stop_bpstat
2649 = bpstat_stop_status (get_regcache_aspace (regcache
),
2650 stop_pc
, ecs
->ptid
);
2651 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2653 if (!ecs
->random_signal
)
2655 /* Catchpoint hit. */
2656 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2661 /* If no catchpoint triggered for this, then keep going. */
2662 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2667 /* Given an execution control state that has been freshly filled in
2668 by an event from the inferior, figure out what it means and take
2669 appropriate action. */
2672 handle_inferior_event (struct execution_control_state
*ecs
)
2674 struct frame_info
*frame
;
2675 struct gdbarch
*gdbarch
;
2676 int sw_single_step_trap_p
= 0;
2677 int stopped_by_watchpoint
;
2678 int stepped_after_stopped_by_watchpoint
= 0;
2679 struct symtab_and_line stop_pc_sal
;
2680 enum stop_kind stop_soon
;
2682 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
2684 /* We had an event in the inferior, but we are not interested in
2685 handling it at this level. The lower layers have already
2686 done what needs to be done, if anything.
2688 One of the possible circumstances for this is when the
2689 inferior produces output for the console. The inferior has
2690 not stopped, and we are ignoring the event. Another possible
2691 circumstance is any event which the lower level knows will be
2692 reported multiple times without an intervening resume. */
2694 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2695 prepare_to_wait (ecs
);
2699 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2700 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2702 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2704 stop_soon
= inf
->stop_soon
;
2707 stop_soon
= NO_STOP_QUIETLY
;
2709 /* Cache the last pid/waitstatus. */
2710 target_last_wait_ptid
= ecs
->ptid
;
2711 target_last_waitstatus
= ecs
->ws
;
2713 /* Always clear state belonging to the previous time we stopped. */
2714 stop_stack_dummy
= 0;
2716 /* If it's a new process, add it to the thread database */
2718 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
2719 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
2720 && !in_thread_list (ecs
->ptid
));
2722 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2723 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
2724 add_thread (ecs
->ptid
);
2726 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
2728 /* Dependent on valid ECS->EVENT_THREAD. */
2729 adjust_pc_after_break (ecs
);
2731 /* Dependent on the current PC value modified by adjust_pc_after_break. */
2732 reinit_frame_cache ();
2734 breakpoint_retire_moribund ();
2736 /* Mark the non-executing threads accordingly. In all-stop, all
2737 threads of all processes are stopped when we get any event
2738 reported. In non-stop mode, only the event thread stops. If
2739 we're handling a process exit in non-stop mode, there's nothing
2740 to do, as threads of the dead process are gone, and threads of
2741 any other process were left running. */
2743 set_executing (minus_one_ptid
, 0);
2744 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2745 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
2746 set_executing (inferior_ptid
, 0);
2748 switch (infwait_state
)
2750 case infwait_thread_hop_state
:
2752 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
2755 case infwait_normal_state
:
2757 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
2760 case infwait_step_watch_state
:
2762 fprintf_unfiltered (gdb_stdlog
,
2763 "infrun: infwait_step_watch_state\n");
2765 stepped_after_stopped_by_watchpoint
= 1;
2768 case infwait_nonstep_watch_state
:
2770 fprintf_unfiltered (gdb_stdlog
,
2771 "infrun: infwait_nonstep_watch_state\n");
2772 insert_breakpoints ();
2774 /* FIXME-maybe: is this cleaner than setting a flag? Does it
2775 handle things like signals arriving and other things happening
2776 in combination correctly? */
2777 stepped_after_stopped_by_watchpoint
= 1;
2781 internal_error (__FILE__
, __LINE__
, _("bad switch"));
2784 infwait_state
= infwait_normal_state
;
2785 waiton_ptid
= pid_to_ptid (-1);
2787 switch (ecs
->ws
.kind
)
2789 case TARGET_WAITKIND_LOADED
:
2791 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
2792 /* Ignore gracefully during startup of the inferior, as it might
2793 be the shell which has just loaded some objects, otherwise
2794 add the symbols for the newly loaded objects. Also ignore at
2795 the beginning of an attach or remote session; we will query
2796 the full list of libraries once the connection is
2798 if (stop_soon
== NO_STOP_QUIETLY
)
2800 /* Check for any newly added shared libraries if we're
2801 supposed to be adding them automatically. Switch
2802 terminal for any messages produced by
2803 breakpoint_re_set. */
2804 target_terminal_ours_for_output ();
2805 /* NOTE: cagney/2003-11-25: Make certain that the target
2806 stack's section table is kept up-to-date. Architectures,
2807 (e.g., PPC64), use the section table to perform
2808 operations such as address => section name and hence
2809 require the table to contain all sections (including
2810 those found in shared libraries). */
2812 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2814 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2816 target_terminal_inferior ();
2818 /* If requested, stop when the dynamic linker notifies
2819 gdb of events. This allows the user to get control
2820 and place breakpoints in initializer routines for
2821 dynamically loaded objects (among other things). */
2822 if (stop_on_solib_events
)
2824 stop_stepping (ecs
);
2828 /* NOTE drow/2007-05-11: This might be a good place to check
2829 for "catch load". */
2832 /* If we are skipping through a shell, or through shared library
2833 loading that we aren't interested in, resume the program. If
2834 we're running the program normally, also resume. But stop if
2835 we're attaching or setting up a remote connection. */
2836 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
2838 /* Loading of shared libraries might have changed breakpoint
2839 addresses. Make sure new breakpoints are inserted. */
2840 if (stop_soon
== NO_STOP_QUIETLY
2841 && !breakpoints_always_inserted_mode ())
2842 insert_breakpoints ();
2843 resume (0, TARGET_SIGNAL_0
);
2844 prepare_to_wait (ecs
);
2850 case TARGET_WAITKIND_SPURIOUS
:
2852 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
2853 resume (0, TARGET_SIGNAL_0
);
2854 prepare_to_wait (ecs
);
2857 case TARGET_WAITKIND_EXITED
:
2859 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
2860 inferior_ptid
= ecs
->ptid
;
2861 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
2862 set_current_program_space (current_inferior ()->pspace
);
2863 handle_vfork_child_exec_or_exit (0);
2864 target_terminal_ours (); /* Must do this before mourn anyway */
2865 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
2867 /* Record the exit code in the convenience variable $_exitcode, so
2868 that the user can inspect this again later. */
2869 set_internalvar_integer (lookup_internalvar ("_exitcode"),
2870 (LONGEST
) ecs
->ws
.value
.integer
);
2871 gdb_flush (gdb_stdout
);
2872 target_mourn_inferior ();
2873 singlestep_breakpoints_inserted_p
= 0;
2874 stop_print_frame
= 0;
2875 stop_stepping (ecs
);
2878 case TARGET_WAITKIND_SIGNALLED
:
2880 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2881 inferior_ptid
= ecs
->ptid
;
2882 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
2883 set_current_program_space (current_inferior ()->pspace
);
2884 handle_vfork_child_exec_or_exit (0);
2885 stop_print_frame
= 0;
2886 target_terminal_ours (); /* Must do this before mourn anyway */
2888 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2889 reach here unless the inferior is dead. However, for years
2890 target_kill() was called here, which hints that fatal signals aren't
2891 really fatal on some systems. If that's true, then some changes
2893 target_mourn_inferior ();
2895 print_stop_reason (SIGNAL_EXITED
, ecs
->ws
.value
.sig
);
2896 singlestep_breakpoints_inserted_p
= 0;
2897 stop_stepping (ecs
);
2900 /* The following are the only cases in which we keep going;
2901 the above cases end in a continue or goto. */
2902 case TARGET_WAITKIND_FORKED
:
2903 case TARGET_WAITKIND_VFORKED
:
2905 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2907 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2909 context_switch (ecs
->ptid
);
2910 reinit_frame_cache ();
2913 /* Immediately detach breakpoints from the child before there's
2914 any chance of letting the user delete breakpoints from the
2915 breakpoint lists. If we don't do this early, it's easy to
2916 leave left over traps in the child, vis: "break foo; catch
2917 fork; c; <fork>; del; c; <child calls foo>". We only follow
2918 the fork on the last `continue', and by that time the
2919 breakpoint at "foo" is long gone from the breakpoint table.
2920 If we vforked, then we don't need to unpatch here, since both
2921 parent and child are sharing the same memory pages; we'll
2922 need to unpatch at follow/detach time instead to be certain
2923 that new breakpoints added between catchpoint hit time and
2924 vfork follow are detached. */
2925 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
2927 int child_pid
= ptid_get_pid (ecs
->ws
.value
.related_pid
);
2929 /* This won't actually modify the breakpoint list, but will
2930 physically remove the breakpoints from the child. */
2931 detach_breakpoints (child_pid
);
2934 /* In case the event is caught by a catchpoint, remember that
2935 the event is to be followed at the next resume of the thread,
2936 and not immediately. */
2937 ecs
->event_thread
->pending_follow
= ecs
->ws
;
2939 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2941 ecs
->event_thread
->stop_bpstat
2942 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
2943 stop_pc
, ecs
->ptid
);
2945 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2947 /* If no catchpoint triggered for this, then keep going. */
2948 if (ecs
->random_signal
)
2953 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
2955 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2957 should_resume
= follow_fork ();
2960 child
= ecs
->ws
.value
.related_pid
;
2962 /* In non-stop mode, also resume the other branch. */
2963 if (non_stop
&& !detach_fork
)
2966 switch_to_thread (parent
);
2968 switch_to_thread (child
);
2970 ecs
->event_thread
= inferior_thread ();
2971 ecs
->ptid
= inferior_ptid
;
2976 switch_to_thread (child
);
2978 switch_to_thread (parent
);
2980 ecs
->event_thread
= inferior_thread ();
2981 ecs
->ptid
= inferior_ptid
;
2986 stop_stepping (ecs
);
2989 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2990 goto process_event_stop_test
;
2992 case TARGET_WAITKIND_VFORK_DONE
:
2993 /* Done with the shared memory region. Re-insert breakpoints in
2994 the parent, and keep going. */
2997 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORK_DONE\n");
2999 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3000 context_switch (ecs
->ptid
);
3002 current_inferior ()->waiting_for_vfork_done
= 0;
3003 /* This also takes care of reinserting breakpoints in the
3004 previously locked inferior. */
3008 case TARGET_WAITKIND_EXECD
:
3010 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3012 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3014 context_switch (ecs
->ptid
);
3015 reinit_frame_cache ();
3018 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3020 /* Do whatever is necessary to the parent branch of the vfork. */
3021 handle_vfork_child_exec_or_exit (1);
3023 /* This causes the eventpoints and symbol table to be reset.
3024 Must do this now, before trying to determine whether to
3026 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3028 ecs
->event_thread
->stop_bpstat
3029 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3030 stop_pc
, ecs
->ptid
);
3031 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
3033 /* Note that this may be referenced from inside
3034 bpstat_stop_status above, through inferior_has_execd. */
3035 xfree (ecs
->ws
.value
.execd_pathname
);
3036 ecs
->ws
.value
.execd_pathname
= NULL
;
3038 /* If no catchpoint triggered for this, then keep going. */
3039 if (ecs
->random_signal
)
3041 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3045 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
3046 goto process_event_stop_test
;
3048 /* Be careful not to try to gather much state about a thread
3049 that's in a syscall. It's frequently a losing proposition. */
3050 case TARGET_WAITKIND_SYSCALL_ENTRY
:
3052 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3053 /* Getting the current syscall number */
3054 if (handle_syscall_event (ecs
) != 0)
3056 goto process_event_stop_test
;
3058 /* Before examining the threads further, step this thread to
3059 get it entirely out of the syscall. (We get notice of the
3060 event when the thread is just on the verge of exiting a
3061 syscall. Stepping one instruction seems to get it back
3063 case TARGET_WAITKIND_SYSCALL_RETURN
:
3065 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3066 if (handle_syscall_event (ecs
) != 0)
3068 goto process_event_stop_test
;
3070 case TARGET_WAITKIND_STOPPED
:
3072 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
3073 ecs
->event_thread
->stop_signal
= ecs
->ws
.value
.sig
;
3076 case TARGET_WAITKIND_NO_HISTORY
:
3077 /* Reverse execution: target ran out of history info. */
3078 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3079 print_stop_reason (NO_HISTORY
, 0);
3080 stop_stepping (ecs
);
3084 if (ecs
->new_thread_event
)
3087 /* Non-stop assumes that the target handles adding new threads
3088 to the thread list. */
3089 internal_error (__FILE__
, __LINE__
, "\
3090 targets should add new threads to the thread list themselves in non-stop mode.");
3092 /* We may want to consider not doing a resume here in order to
3093 give the user a chance to play with the new thread. It might
3094 be good to make that a user-settable option. */
3096 /* At this point, all threads are stopped (happens automatically
3097 in either the OS or the native code). Therefore we need to
3098 continue all threads in order to make progress. */
3100 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3101 context_switch (ecs
->ptid
);
3102 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
3103 prepare_to_wait (ecs
);
3107 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
3109 /* Do we need to clean up the state of a thread that has
3110 completed a displaced single-step? (Doing so usually affects
3111 the PC, so do it here, before we set stop_pc.) */
3112 displaced_step_fixup (ecs
->ptid
, ecs
->event_thread
->stop_signal
);
3114 /* If we either finished a single-step or hit a breakpoint, but
3115 the user wanted this thread to be stopped, pretend we got a
3116 SIG0 (generic unsignaled stop). */
3118 if (ecs
->event_thread
->stop_requested
3119 && ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
3120 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3123 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3127 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3128 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3130 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
3131 paddress (gdbarch
, stop_pc
));
3132 if (target_stopped_by_watchpoint ())
3135 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
3137 if (target_stopped_data_address (¤t_target
, &addr
))
3138 fprintf_unfiltered (gdb_stdlog
,
3139 "infrun: stopped data address = %s\n",
3140 paddress (gdbarch
, addr
));
3142 fprintf_unfiltered (gdb_stdlog
,
3143 "infrun: (no data address available)\n");
3147 if (stepping_past_singlestep_breakpoint
)
3149 gdb_assert (singlestep_breakpoints_inserted_p
);
3150 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
3151 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
3153 stepping_past_singlestep_breakpoint
= 0;
3155 /* We've either finished single-stepping past the single-step
3156 breakpoint, or stopped for some other reason. It would be nice if
3157 we could tell, but we can't reliably. */
3158 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
3161 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
3162 /* Pull the single step breakpoints out of the target. */
3163 remove_single_step_breakpoints ();
3164 singlestep_breakpoints_inserted_p
= 0;
3166 ecs
->random_signal
= 0;
3167 ecs
->event_thread
->trap_expected
= 0;
3169 context_switch (saved_singlestep_ptid
);
3170 if (deprecated_context_hook
)
3171 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3173 resume (1, TARGET_SIGNAL_0
);
3174 prepare_to_wait (ecs
);
3179 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
3181 /* In non-stop mode, there's never a deferred_step_ptid set. */
3182 gdb_assert (!non_stop
);
3184 /* If we stopped for some other reason than single-stepping, ignore
3185 the fact that we were supposed to switch back. */
3186 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
3189 fprintf_unfiltered (gdb_stdlog
,
3190 "infrun: handling deferred step\n");
3192 /* Pull the single step breakpoints out of the target. */
3193 if (singlestep_breakpoints_inserted_p
)
3195 remove_single_step_breakpoints ();
3196 singlestep_breakpoints_inserted_p
= 0;
3199 /* Note: We do not call context_switch at this point, as the
3200 context is already set up for stepping the original thread. */
3201 switch_to_thread (deferred_step_ptid
);
3202 deferred_step_ptid
= null_ptid
;
3203 /* Suppress spurious "Switching to ..." message. */
3204 previous_inferior_ptid
= inferior_ptid
;
3206 resume (1, TARGET_SIGNAL_0
);
3207 prepare_to_wait (ecs
);
3211 deferred_step_ptid
= null_ptid
;
3214 /* See if a thread hit a thread-specific breakpoint that was meant for
3215 another thread. If so, then step that thread past the breakpoint,
3218 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
3220 int thread_hop_needed
= 0;
3221 struct address_space
*aspace
= get_regcache_aspace (get_current_regcache ());
3223 /* Check if a regular breakpoint has been hit before checking
3224 for a potential single step breakpoint. Otherwise, GDB will
3225 not see this breakpoint hit when stepping onto breakpoints. */
3226 if (regular_breakpoint_inserted_here_p (aspace
, stop_pc
))
3228 ecs
->random_signal
= 0;
3229 if (!breakpoint_thread_match (aspace
, stop_pc
, ecs
->ptid
))
3230 thread_hop_needed
= 1;
3232 else if (singlestep_breakpoints_inserted_p
)
3234 /* We have not context switched yet, so this should be true
3235 no matter which thread hit the singlestep breakpoint. */
3236 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
3238 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
3240 target_pid_to_str (ecs
->ptid
));
3242 ecs
->random_signal
= 0;
3243 /* The call to in_thread_list is necessary because PTIDs sometimes
3244 change when we go from single-threaded to multi-threaded. If
3245 the singlestep_ptid is still in the list, assume that it is
3246 really different from ecs->ptid. */
3247 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
3248 && in_thread_list (singlestep_ptid
))
3250 /* If the PC of the thread we were trying to single-step
3251 has changed, discard this event (which we were going
3252 to ignore anyway), and pretend we saw that thread
3253 trap. This prevents us continuously moving the
3254 single-step breakpoint forward, one instruction at a
3255 time. If the PC has changed, then the thread we were
3256 trying to single-step has trapped or been signalled,
3257 but the event has not been reported to GDB yet.
3259 There might be some cases where this loses signal
3260 information, if a signal has arrived at exactly the
3261 same time that the PC changed, but this is the best
3262 we can do with the information available. Perhaps we
3263 should arrange to report all events for all threads
3264 when they stop, or to re-poll the remote looking for
3265 this particular thread (i.e. temporarily enable
3268 CORE_ADDR new_singlestep_pc
3269 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
3271 if (new_singlestep_pc
!= singlestep_pc
)
3273 enum target_signal stop_signal
;
3276 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
3277 " but expected thread advanced also\n");
3279 /* The current context still belongs to
3280 singlestep_ptid. Don't swap here, since that's
3281 the context we want to use. Just fudge our
3282 state and continue. */
3283 stop_signal
= ecs
->event_thread
->stop_signal
;
3284 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3285 ecs
->ptid
= singlestep_ptid
;
3286 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3287 ecs
->event_thread
->stop_signal
= stop_signal
;
3288 stop_pc
= new_singlestep_pc
;
3293 fprintf_unfiltered (gdb_stdlog
,
3294 "infrun: unexpected thread\n");
3296 thread_hop_needed
= 1;
3297 stepping_past_singlestep_breakpoint
= 1;
3298 saved_singlestep_ptid
= singlestep_ptid
;
3303 if (thread_hop_needed
)
3305 struct regcache
*thread_regcache
;
3306 int remove_status
= 0;
3309 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3311 /* Switch context before touching inferior memory, the
3312 previous thread may have exited. */
3313 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3314 context_switch (ecs
->ptid
);
3316 /* Saw a breakpoint, but it was hit by the wrong thread.
3319 if (singlestep_breakpoints_inserted_p
)
3321 /* Pull the single step breakpoints out of the target. */
3322 remove_single_step_breakpoints ();
3323 singlestep_breakpoints_inserted_p
= 0;
3326 /* If the arch can displace step, don't remove the
3328 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3329 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3330 remove_status
= remove_breakpoints ();
3332 /* Did we fail to remove breakpoints? If so, try
3333 to set the PC past the bp. (There's at least
3334 one situation in which we can fail to remove
3335 the bp's: On HP-UX's that use ttrace, we can't
3336 change the address space of a vforking child
3337 process until the child exits (well, okay, not
3338 then either :-) or execs. */
3339 if (remove_status
!= 0)
3340 error (_("Cannot step over breakpoint hit in wrong thread"));
3345 /* Only need to require the next event from this
3346 thread in all-stop mode. */
3347 waiton_ptid
= ecs
->ptid
;
3348 infwait_state
= infwait_thread_hop_state
;
3351 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3356 else if (singlestep_breakpoints_inserted_p
)
3358 sw_single_step_trap_p
= 1;
3359 ecs
->random_signal
= 0;
3363 ecs
->random_signal
= 1;
3365 /* See if something interesting happened to the non-current thread. If
3366 so, then switch to that thread. */
3367 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3370 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3372 context_switch (ecs
->ptid
);
3374 if (deprecated_context_hook
)
3375 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3378 /* At this point, get hold of the now-current thread's frame. */
3379 frame
= get_current_frame ();
3380 gdbarch
= get_frame_arch (frame
);
3382 if (singlestep_breakpoints_inserted_p
)
3384 /* Pull the single step breakpoints out of the target. */
3385 remove_single_step_breakpoints ();
3386 singlestep_breakpoints_inserted_p
= 0;
3389 if (stepped_after_stopped_by_watchpoint
)
3390 stopped_by_watchpoint
= 0;
3392 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
3394 /* If necessary, step over this watchpoint. We'll be back to display
3396 if (stopped_by_watchpoint
3397 && (target_have_steppable_watchpoint
3398 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
3400 /* At this point, we are stopped at an instruction which has
3401 attempted to write to a piece of memory under control of
3402 a watchpoint. The instruction hasn't actually executed
3403 yet. If we were to evaluate the watchpoint expression
3404 now, we would get the old value, and therefore no change
3405 would seem to have occurred.
3407 In order to make watchpoints work `right', we really need
3408 to complete the memory write, and then evaluate the
3409 watchpoint expression. We do this by single-stepping the
3412 It may not be necessary to disable the watchpoint to stop over
3413 it. For example, the PA can (with some kernel cooperation)
3414 single step over a watchpoint without disabling the watchpoint.
3416 It is far more common to need to disable a watchpoint to step
3417 the inferior over it. If we have non-steppable watchpoints,
3418 we must disable the current watchpoint; it's simplest to
3419 disable all watchpoints and breakpoints. */
3422 if (!target_have_steppable_watchpoint
)
3423 remove_breakpoints ();
3425 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
3426 target_resume (ecs
->ptid
, hw_step
, TARGET_SIGNAL_0
);
3427 waiton_ptid
= ecs
->ptid
;
3428 if (target_have_steppable_watchpoint
)
3429 infwait_state
= infwait_step_watch_state
;
3431 infwait_state
= infwait_nonstep_watch_state
;
3432 prepare_to_wait (ecs
);
3436 ecs
->stop_func_start
= 0;
3437 ecs
->stop_func_end
= 0;
3438 ecs
->stop_func_name
= 0;
3439 /* Don't care about return value; stop_func_start and stop_func_name
3440 will both be 0 if it doesn't work. */
3441 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3442 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3443 ecs
->stop_func_start
3444 += gdbarch_deprecated_function_start_offset (gdbarch
);
3445 ecs
->event_thread
->stepping_over_breakpoint
= 0;
3446 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
3447 ecs
->event_thread
->stop_step
= 0;
3448 stop_print_frame
= 1;
3449 ecs
->random_signal
= 0;
3450 stopped_by_random_signal
= 0;
3452 /* Hide inlined functions starting here, unless we just performed stepi or
3453 nexti. After stepi and nexti, always show the innermost frame (not any
3454 inline function call sites). */
3455 if (ecs
->event_thread
->step_range_end
!= 1)
3456 skip_inline_frames (ecs
->ptid
);
3458 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3459 && ecs
->event_thread
->trap_expected
3460 && gdbarch_single_step_through_delay_p (gdbarch
)
3461 && currently_stepping (ecs
->event_thread
))
3463 /* We're trying to step off a breakpoint. Turns out that we're
3464 also on an instruction that needs to be stepped multiple
3465 times before it's been fully executing. E.g., architectures
3466 with a delay slot. It needs to be stepped twice, once for
3467 the instruction and once for the delay slot. */
3468 int step_through_delay
3469 = gdbarch_single_step_through_delay (gdbarch
, frame
);
3470 if (debug_infrun
&& step_through_delay
)
3471 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
3472 if (ecs
->event_thread
->step_range_end
== 0 && step_through_delay
)
3474 /* The user issued a continue when stopped at a breakpoint.
3475 Set up for another trap and get out of here. */
3476 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3480 else if (step_through_delay
)
3482 /* The user issued a step when stopped at a breakpoint.
3483 Maybe we should stop, maybe we should not - the delay
3484 slot *might* correspond to a line of source. In any
3485 case, don't decide that here, just set
3486 ecs->stepping_over_breakpoint, making sure we
3487 single-step again before breakpoints are re-inserted. */
3488 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3492 /* Look at the cause of the stop, and decide what to do.
3493 The alternatives are:
3494 1) stop_stepping and return; to really stop and return to the debugger,
3495 2) keep_going and return to start up again
3496 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
3497 3) set ecs->random_signal to 1, and the decision between 1 and 2
3498 will be made according to the signal handling tables. */
3500 /* First, distinguish signals caused by the debugger from signals
3501 that have to do with the program's own actions. Note that
3502 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3503 on the operating system version. Here we detect when a SIGILL or
3504 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3505 something similar for SIGSEGV, since a SIGSEGV will be generated
3506 when we're trying to execute a breakpoint instruction on a
3507 non-executable stack. This happens for call dummy breakpoints
3508 for architectures like SPARC that place call dummies on the
3511 If we're doing a displaced step past a breakpoint, then the
3512 breakpoint is always inserted at the original instruction;
3513 non-standard signals can't be explained by the breakpoint. */
3514 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3515 || (! ecs
->event_thread
->trap_expected
3516 && breakpoint_inserted_here_p (get_regcache_aspace (get_current_regcache ()),
3518 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_ILL
3519 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_SEGV
3520 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_EMT
))
3521 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3522 || stop_soon
== STOP_QUIETLY_REMOTE
)
3524 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
3527 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
3528 stop_print_frame
= 0;
3529 stop_stepping (ecs
);
3533 /* This is originated from start_remote(), start_inferior() and
3534 shared libraries hook functions. */
3535 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
3538 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3539 stop_stepping (ecs
);
3543 /* This originates from attach_command(). We need to overwrite
3544 the stop_signal here, because some kernels don't ignore a
3545 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
3546 See more comments in inferior.h. On the other hand, if we
3547 get a non-SIGSTOP, report it to the user - assume the backend
3548 will handle the SIGSTOP if it should show up later.
3550 Also consider that the attach is complete when we see a
3551 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
3552 target extended-remote report it instead of a SIGSTOP
3553 (e.g. gdbserver). We already rely on SIGTRAP being our
3554 signal, so this is no exception.
3556 Also consider that the attach is complete when we see a
3557 TARGET_SIGNAL_0. In non-stop mode, GDB will explicitly tell
3558 the target to stop all threads of the inferior, in case the
3559 low level attach operation doesn't stop them implicitly. If
3560 they weren't stopped implicitly, then the stub will report a
3561 TARGET_SIGNAL_0, meaning: stopped for no particular reason
3562 other than GDB's request. */
3563 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3564 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_STOP
3565 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3566 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_0
))
3568 stop_stepping (ecs
);
3569 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3573 /* See if there is a breakpoint at the current PC. */
3574 ecs
->event_thread
->stop_bpstat
3575 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3576 stop_pc
, ecs
->ptid
);
3578 /* Following in case break condition called a
3580 stop_print_frame
= 1;
3582 /* NOTE: cagney/2003-03-29: These two checks for a random signal
3583 at one stage in the past included checks for an inferior
3584 function call's call dummy's return breakpoint. The original
3585 comment, that went with the test, read:
3587 ``End of a stack dummy. Some systems (e.g. Sony news) give
3588 another signal besides SIGTRAP, so check here as well as
3591 If someone ever tries to get call dummys on a
3592 non-executable stack to work (where the target would stop
3593 with something like a SIGSEGV), then those tests might need
3594 to be re-instated. Given, however, that the tests were only
3595 enabled when momentary breakpoints were not being used, I
3596 suspect that it won't be the case.
3598 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
3599 be necessary for call dummies on a non-executable stack on
3602 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
3604 = !(bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
)
3605 || ecs
->event_thread
->trap_expected
3606 || (ecs
->event_thread
->step_range_end
3607 && ecs
->event_thread
->step_resume_breakpoint
== NULL
));
3610 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
3611 if (!ecs
->random_signal
)
3612 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
3616 /* When we reach this point, we've pretty much decided
3617 that the reason for stopping must've been a random
3618 (unexpected) signal. */
3621 ecs
->random_signal
= 1;
3623 process_event_stop_test
:
3625 /* Re-fetch current thread's frame in case we did a
3626 "goto process_event_stop_test" above. */
3627 frame
= get_current_frame ();
3628 gdbarch
= get_frame_arch (frame
);
3630 /* For the program's own signals, act according to
3631 the signal handling tables. */
3633 if (ecs
->random_signal
)
3635 /* Signal not for debugging purposes. */
3639 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
3640 ecs
->event_thread
->stop_signal
);
3642 stopped_by_random_signal
= 1;
3644 if (signal_print
[ecs
->event_thread
->stop_signal
])
3647 target_terminal_ours_for_output ();
3648 print_stop_reason (SIGNAL_RECEIVED
, ecs
->event_thread
->stop_signal
);
3650 /* Always stop on signals if we're either just gaining control
3651 of the program, or the user explicitly requested this thread
3652 to remain stopped. */
3653 if (stop_soon
!= NO_STOP_QUIETLY
3654 || ecs
->event_thread
->stop_requested
3655 || signal_stop_state (ecs
->event_thread
->stop_signal
))
3657 stop_stepping (ecs
);
3660 /* If not going to stop, give terminal back
3661 if we took it away. */
3663 target_terminal_inferior ();
3665 /* Clear the signal if it should not be passed. */
3666 if (signal_program
[ecs
->event_thread
->stop_signal
] == 0)
3667 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3669 if (ecs
->event_thread
->prev_pc
== stop_pc
3670 && ecs
->event_thread
->trap_expected
3671 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
3673 /* We were just starting a new sequence, attempting to
3674 single-step off of a breakpoint and expecting a SIGTRAP.
3675 Instead this signal arrives. This signal will take us out
3676 of the stepping range so GDB needs to remember to, when
3677 the signal handler returns, resume stepping off that
3679 /* To simplify things, "continue" is forced to use the same
3680 code paths as single-step - set a breakpoint at the
3681 signal return address and then, once hit, step off that
3684 fprintf_unfiltered (gdb_stdlog
,
3685 "infrun: signal arrived while stepping over "
3688 insert_step_resume_breakpoint_at_frame (frame
);
3689 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
3694 if (ecs
->event_thread
->step_range_end
!= 0
3695 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_0
3696 && (ecs
->event_thread
->step_range_start
<= stop_pc
3697 && stop_pc
< ecs
->event_thread
->step_range_end
)
3698 && frame_id_eq (get_stack_frame_id (frame
),
3699 ecs
->event_thread
->step_stack_frame_id
)
3700 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
3702 /* The inferior is about to take a signal that will take it
3703 out of the single step range. Set a breakpoint at the
3704 current PC (which is presumably where the signal handler
3705 will eventually return) and then allow the inferior to
3708 Note that this is only needed for a signal delivered
3709 while in the single-step range. Nested signals aren't a
3710 problem as they eventually all return. */
3712 fprintf_unfiltered (gdb_stdlog
,
3713 "infrun: signal may take us out of "
3714 "single-step range\n");
3716 insert_step_resume_breakpoint_at_frame (frame
);
3721 /* Note: step_resume_breakpoint may be non-NULL. This occures
3722 when either there's a nested signal, or when there's a
3723 pending signal enabled just as the signal handler returns
3724 (leaving the inferior at the step-resume-breakpoint without
3725 actually executing it). Either way continue until the
3726 breakpoint is really hit. */
3731 /* Handle cases caused by hitting a breakpoint. */
3733 CORE_ADDR jmp_buf_pc
;
3734 struct bpstat_what what
;
3736 what
= bpstat_what (ecs
->event_thread
->stop_bpstat
);
3738 if (what
.call_dummy
)
3740 stop_stack_dummy
= 1;
3743 switch (what
.main_action
)
3745 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
3746 /* If we hit the breakpoint at longjmp while stepping, we
3747 install a momentary breakpoint at the target of the
3751 fprintf_unfiltered (gdb_stdlog
,
3752 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
3754 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3756 if (!gdbarch_get_longjmp_target_p (gdbarch
)
3757 || !gdbarch_get_longjmp_target (gdbarch
, frame
, &jmp_buf_pc
))
3760 fprintf_unfiltered (gdb_stdlog
, "\
3761 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
3766 /* We're going to replace the current step-resume breakpoint
3767 with a longjmp-resume breakpoint. */
3768 delete_step_resume_breakpoint (ecs
->event_thread
);
3770 /* Insert a breakpoint at resume address. */
3771 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
3776 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
3778 fprintf_unfiltered (gdb_stdlog
,
3779 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
3781 gdb_assert (ecs
->event_thread
->step_resume_breakpoint
!= NULL
);
3782 delete_step_resume_breakpoint (ecs
->event_thread
);
3784 ecs
->event_thread
->stop_step
= 1;
3785 print_stop_reason (END_STEPPING_RANGE
, 0);
3786 stop_stepping (ecs
);
3789 case BPSTAT_WHAT_SINGLE
:
3791 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
3792 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3793 /* Still need to check other stuff, at least the case
3794 where we are stepping and step out of the right range. */
3797 case BPSTAT_WHAT_STOP_NOISY
:
3799 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
3800 stop_print_frame
= 1;
3802 /* We are about to nuke the step_resume_breakpointt via the
3803 cleanup chain, so no need to worry about it here. */
3805 stop_stepping (ecs
);
3808 case BPSTAT_WHAT_STOP_SILENT
:
3810 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
3811 stop_print_frame
= 0;
3813 /* We are about to nuke the step_resume_breakpoin via the
3814 cleanup chain, so no need to worry about it here. */
3816 stop_stepping (ecs
);
3819 case BPSTAT_WHAT_STEP_RESUME
:
3821 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
3823 delete_step_resume_breakpoint (ecs
->event_thread
);
3824 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
3826 /* Back when the step-resume breakpoint was inserted, we
3827 were trying to single-step off a breakpoint. Go back
3829 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
3830 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3834 if (stop_pc
== ecs
->stop_func_start
3835 && execution_direction
== EXEC_REVERSE
)
3837 /* We are stepping over a function call in reverse, and
3838 just hit the step-resume breakpoint at the start
3839 address of the function. Go back to single-stepping,
3840 which should take us back to the function call. */
3841 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3847 case BPSTAT_WHAT_CHECK_SHLIBS
:
3850 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
3852 /* Check for any newly added shared libraries if we're
3853 supposed to be adding them automatically. Switch
3854 terminal for any messages produced by
3855 breakpoint_re_set. */
3856 target_terminal_ours_for_output ();
3857 /* NOTE: cagney/2003-11-25: Make certain that the target
3858 stack's section table is kept up-to-date. Architectures,
3859 (e.g., PPC64), use the section table to perform
3860 operations such as address => section name and hence
3861 require the table to contain all sections (including
3862 those found in shared libraries). */
3864 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
3866 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
3868 target_terminal_inferior ();
3870 /* If requested, stop when the dynamic linker notifies
3871 gdb of events. This allows the user to get control
3872 and place breakpoints in initializer routines for
3873 dynamically loaded objects (among other things). */
3874 if (stop_on_solib_events
|| stop_stack_dummy
)
3876 stop_stepping (ecs
);
3881 /* We want to step over this breakpoint, then keep going. */
3882 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3888 case BPSTAT_WHAT_CHECK_JIT
:
3890 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_JIT\n");
3892 /* Switch terminal for any messages produced by breakpoint_re_set. */
3893 target_terminal_ours_for_output ();
3895 jit_event_handler (gdbarch
);
3897 target_terminal_inferior ();
3899 /* We want to step over this breakpoint, then keep going. */
3900 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3904 case BPSTAT_WHAT_LAST
:
3905 /* Not a real code, but listed here to shut up gcc -Wall. */
3907 case BPSTAT_WHAT_KEEP_CHECKING
:
3912 /* We come here if we hit a breakpoint but should not
3913 stop for it. Possibly we also were stepping
3914 and should stop for that. So fall through and
3915 test for stepping. But, if not stepping,
3918 /* In all-stop mode, if we're currently stepping but have stopped in
3919 some other thread, we need to switch back to the stepped thread. */
3922 struct thread_info
*tp
;
3923 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
3927 /* However, if the current thread is blocked on some internal
3928 breakpoint, and we simply need to step over that breakpoint
3929 to get it going again, do that first. */
3930 if ((ecs
->event_thread
->trap_expected
3931 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
3932 || ecs
->event_thread
->stepping_over_breakpoint
)
3938 /* If the stepping thread exited, then don't try to switch
3939 back and resume it, which could fail in several different
3940 ways depending on the target. Instead, just keep going.
3942 We can find a stepping dead thread in the thread list in
3945 - The target supports thread exit events, and when the
3946 target tries to delete the thread from the thread list,
3947 inferior_ptid pointed at the exiting thread. In such
3948 case, calling delete_thread does not really remove the
3949 thread from the list; instead, the thread is left listed,
3950 with 'exited' state.
3952 - The target's debug interface does not support thread
3953 exit events, and so we have no idea whatsoever if the
3954 previously stepping thread is still alive. For that
3955 reason, we need to synchronously query the target
3957 if (is_exited (tp
->ptid
)
3958 || !target_thread_alive (tp
->ptid
))
3961 fprintf_unfiltered (gdb_stdlog
, "\
3962 infrun: not switching back to stepped thread, it has vanished\n");
3964 delete_thread (tp
->ptid
);
3969 /* Otherwise, we no longer expect a trap in the current thread.
3970 Clear the trap_expected flag before switching back -- this is
3971 what keep_going would do as well, if we called it. */
3972 ecs
->event_thread
->trap_expected
= 0;
3975 fprintf_unfiltered (gdb_stdlog
,
3976 "infrun: switching back to stepped thread\n");
3978 ecs
->event_thread
= tp
;
3979 ecs
->ptid
= tp
->ptid
;
3980 context_switch (ecs
->ptid
);
3986 /* Are we stepping to get the inferior out of the dynamic linker's
3987 hook (and possibly the dld itself) after catching a shlib
3989 if (ecs
->event_thread
->stepping_through_solib_after_catch
)
3991 #if defined(SOLIB_ADD)
3992 /* Have we reached our destination? If not, keep going. */
3993 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
3996 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
3997 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4003 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
4004 /* Else, stop and report the catchpoint(s) whose triggering
4005 caused us to begin stepping. */
4006 ecs
->event_thread
->stepping_through_solib_after_catch
= 0;
4007 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
4008 ecs
->event_thread
->stop_bpstat
4009 = bpstat_copy (ecs
->event_thread
->stepping_through_solib_catchpoints
);
4010 bpstat_clear (&ecs
->event_thread
->stepping_through_solib_catchpoints
);
4011 stop_print_frame
= 1;
4012 stop_stepping (ecs
);
4016 if (ecs
->event_thread
->step_resume_breakpoint
)
4019 fprintf_unfiltered (gdb_stdlog
,
4020 "infrun: step-resume breakpoint is inserted\n");
4022 /* Having a step-resume breakpoint overrides anything
4023 else having to do with stepping commands until
4024 that breakpoint is reached. */
4029 if (ecs
->event_thread
->step_range_end
== 0)
4032 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4033 /* Likewise if we aren't even stepping. */
4038 /* If stepping through a line, keep going if still within it.
4040 Note that step_range_end is the address of the first instruction
4041 beyond the step range, and NOT the address of the last instruction
4044 Note also that during reverse execution, we may be stepping
4045 through a function epilogue and therefore must detect when
4046 the current-frame changes in the middle of a line. */
4048 if (stop_pc
>= ecs
->event_thread
->step_range_start
4049 && stop_pc
< ecs
->event_thread
->step_range_end
4050 && (execution_direction
!= EXEC_REVERSE
4051 || frame_id_eq (get_frame_id (frame
),
4052 ecs
->event_thread
->step_frame_id
)))
4056 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4057 paddress (gdbarch
, ecs
->event_thread
->step_range_start
),
4058 paddress (gdbarch
, ecs
->event_thread
->step_range_end
));
4060 /* When stepping backward, stop at beginning of line range
4061 (unless it's the function entry point, in which case
4062 keep going back to the call point). */
4063 if (stop_pc
== ecs
->event_thread
->step_range_start
4064 && stop_pc
!= ecs
->stop_func_start
4065 && execution_direction
== EXEC_REVERSE
)
4067 ecs
->event_thread
->stop_step
= 1;
4068 print_stop_reason (END_STEPPING_RANGE
, 0);
4069 stop_stepping (ecs
);
4077 /* We stepped out of the stepping range. */
4079 /* If we are stepping at the source level and entered the runtime
4080 loader dynamic symbol resolution code...
4082 EXEC_FORWARD: we keep on single stepping until we exit the run
4083 time loader code and reach the callee's address.
4085 EXEC_REVERSE: we've already executed the callee (backward), and
4086 the runtime loader code is handled just like any other
4087 undebuggable function call. Now we need only keep stepping
4088 backward through the trampoline code, and that's handled further
4089 down, so there is nothing for us to do here. */
4091 if (execution_direction
!= EXEC_REVERSE
4092 && ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
4093 && in_solib_dynsym_resolve_code (stop_pc
))
4095 CORE_ADDR pc_after_resolver
=
4096 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4099 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
4101 if (pc_after_resolver
)
4103 /* Set up a step-resume breakpoint at the address
4104 indicated by SKIP_SOLIB_RESOLVER. */
4105 struct symtab_and_line sr_sal
;
4107 sr_sal
.pc
= pc_after_resolver
;
4108 sr_sal
.pspace
= get_frame_program_space (frame
);
4110 insert_step_resume_breakpoint_at_sal (gdbarch
,
4111 sr_sal
, null_frame_id
);
4118 if (ecs
->event_thread
->step_range_end
!= 1
4119 && (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
4120 || ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
4121 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4124 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
4125 /* The inferior, while doing a "step" or "next", has ended up in
4126 a signal trampoline (either by a signal being delivered or by
4127 the signal handler returning). Just single-step until the
4128 inferior leaves the trampoline (either by calling the handler
4134 /* Check for subroutine calls. The check for the current frame
4135 equalling the step ID is not necessary - the check of the
4136 previous frame's ID is sufficient - but it is a common case and
4137 cheaper than checking the previous frame's ID.
4139 NOTE: frame_id_eq will never report two invalid frame IDs as
4140 being equal, so to get into this block, both the current and
4141 previous frame must have valid frame IDs. */
4142 /* The outer_frame_id check is a heuristic to detect stepping
4143 through startup code. If we step over an instruction which
4144 sets the stack pointer from an invalid value to a valid value,
4145 we may detect that as a subroutine call from the mythical
4146 "outermost" function. This could be fixed by marking
4147 outermost frames as !stack_p,code_p,special_p. Then the
4148 initial outermost frame, before sp was valid, would
4149 have code_addr == &_start. See the commend in frame_id_eq
4151 if (!frame_id_eq (get_stack_frame_id (frame
),
4152 ecs
->event_thread
->step_stack_frame_id
)
4153 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4154 ecs
->event_thread
->step_stack_frame_id
)
4155 && (!frame_id_eq (ecs
->event_thread
->step_stack_frame_id
,
4157 || step_start_function
!= find_pc_function (stop_pc
))))
4159 CORE_ADDR real_stop_pc
;
4162 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4164 if ((ecs
->event_thread
->step_over_calls
== STEP_OVER_NONE
)
4165 || ((ecs
->event_thread
->step_range_end
== 1)
4166 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4167 ecs
->stop_func_start
)))
4169 /* I presume that step_over_calls is only 0 when we're
4170 supposed to be stepping at the assembly language level
4171 ("stepi"). Just stop. */
4172 /* Also, maybe we just did a "nexti" inside a prolog, so we
4173 thought it was a subroutine call but it was not. Stop as
4175 /* And this works the same backward as frontward. MVS */
4176 ecs
->event_thread
->stop_step
= 1;
4177 print_stop_reason (END_STEPPING_RANGE
, 0);
4178 stop_stepping (ecs
);
4182 /* Reverse stepping through solib trampolines. */
4184 if (execution_direction
== EXEC_REVERSE
4185 && ecs
->event_thread
->step_over_calls
!= STEP_OVER_NONE
4186 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4187 || (ecs
->stop_func_start
== 0
4188 && in_solib_dynsym_resolve_code (stop_pc
))))
4190 /* Any solib trampoline code can be handled in reverse
4191 by simply continuing to single-step. We have already
4192 executed the solib function (backwards), and a few
4193 steps will take us back through the trampoline to the
4199 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
4201 /* We're doing a "next".
4203 Normal (forward) execution: set a breakpoint at the
4204 callee's return address (the address at which the caller
4207 Reverse (backward) execution. set the step-resume
4208 breakpoint at the start of the function that we just
4209 stepped into (backwards), and continue to there. When we
4210 get there, we'll need to single-step back to the caller. */
4212 if (execution_direction
== EXEC_REVERSE
)
4214 struct symtab_and_line sr_sal
;
4216 /* Normal function call return (static or dynamic). */
4218 sr_sal
.pc
= ecs
->stop_func_start
;
4219 sr_sal
.pspace
= get_frame_program_space (frame
);
4220 insert_step_resume_breakpoint_at_sal (gdbarch
,
4221 sr_sal
, null_frame_id
);
4224 insert_step_resume_breakpoint_at_caller (frame
);
4230 /* If we are in a function call trampoline (a stub between the
4231 calling routine and the real function), locate the real
4232 function. That's what tells us (a) whether we want to step
4233 into it at all, and (b) what prologue we want to run to the
4234 end of, if we do step into it. */
4235 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
4236 if (real_stop_pc
== 0)
4237 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4238 if (real_stop_pc
!= 0)
4239 ecs
->stop_func_start
= real_stop_pc
;
4241 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
4243 struct symtab_and_line sr_sal
;
4245 sr_sal
.pc
= ecs
->stop_func_start
;
4246 sr_sal
.pspace
= get_frame_program_space (frame
);
4248 insert_step_resume_breakpoint_at_sal (gdbarch
,
4249 sr_sal
, null_frame_id
);
4254 /* If we have line number information for the function we are
4255 thinking of stepping into, step into it.
4257 If there are several symtabs at that PC (e.g. with include
4258 files), just want to know whether *any* of them have line
4259 numbers. find_pc_line handles this. */
4261 struct symtab_and_line tmp_sal
;
4263 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4264 if (tmp_sal
.line
!= 0)
4266 if (execution_direction
== EXEC_REVERSE
)
4267 handle_step_into_function_backward (gdbarch
, ecs
);
4269 handle_step_into_function (gdbarch
, ecs
);
4274 /* If we have no line number and the step-stop-if-no-debug is
4275 set, we stop the step so that the user has a chance to switch
4276 in assembly mode. */
4277 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
4278 && step_stop_if_no_debug
)
4280 ecs
->event_thread
->stop_step
= 1;
4281 print_stop_reason (END_STEPPING_RANGE
, 0);
4282 stop_stepping (ecs
);
4286 if (execution_direction
== EXEC_REVERSE
)
4288 /* Set a breakpoint at callee's start address.
4289 From there we can step once and be back in the caller. */
4290 struct symtab_and_line sr_sal
;
4292 sr_sal
.pc
= ecs
->stop_func_start
;
4293 sr_sal
.pspace
= get_frame_program_space (frame
);
4294 insert_step_resume_breakpoint_at_sal (gdbarch
,
4295 sr_sal
, null_frame_id
);
4298 /* Set a breakpoint at callee's return address (the address
4299 at which the caller will resume). */
4300 insert_step_resume_breakpoint_at_caller (frame
);
4306 /* Reverse stepping through solib trampolines. */
4308 if (execution_direction
== EXEC_REVERSE
4309 && ecs
->event_thread
->step_over_calls
!= STEP_OVER_NONE
)
4311 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4312 || (ecs
->stop_func_start
== 0
4313 && in_solib_dynsym_resolve_code (stop_pc
)))
4315 /* Any solib trampoline code can be handled in reverse
4316 by simply continuing to single-step. We have already
4317 executed the solib function (backwards), and a few
4318 steps will take us back through the trampoline to the
4323 else if (in_solib_dynsym_resolve_code (stop_pc
))
4325 /* Stepped backward into the solib dynsym resolver.
4326 Set a breakpoint at its start and continue, then
4327 one more step will take us out. */
4328 struct symtab_and_line sr_sal
;
4330 sr_sal
.pc
= ecs
->stop_func_start
;
4331 insert_step_resume_breakpoint_at_sal (gdbarch
,
4332 sr_sal
, null_frame_id
);
4338 /* If we're in the return path from a shared library trampoline,
4339 we want to proceed through the trampoline when stepping. */
4340 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4341 stop_pc
, ecs
->stop_func_name
))
4343 /* Determine where this trampoline returns. */
4344 CORE_ADDR real_stop_pc
;
4345 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4348 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
4350 /* Only proceed through if we know where it's going. */
4353 /* And put the step-breakpoint there and go until there. */
4354 struct symtab_and_line sr_sal
;
4356 init_sal (&sr_sal
); /* initialize to zeroes */
4357 sr_sal
.pc
= real_stop_pc
;
4358 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4359 sr_sal
.pspace
= get_frame_program_space (frame
);
4361 /* Do not specify what the fp should be when we stop since
4362 on some machines the prologue is where the new fp value
4364 insert_step_resume_breakpoint_at_sal (gdbarch
,
4365 sr_sal
, null_frame_id
);
4367 /* Restart without fiddling with the step ranges or
4374 stop_pc_sal
= find_pc_line (stop_pc
, 0);
4376 /* NOTE: tausq/2004-05-24: This if block used to be done before all
4377 the trampoline processing logic, however, there are some trampolines
4378 that have no names, so we should do trampoline handling first. */
4379 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
4380 && ecs
->stop_func_name
== NULL
4381 && stop_pc_sal
.line
== 0)
4384 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
4386 /* The inferior just stepped into, or returned to, an
4387 undebuggable function (where there is no debugging information
4388 and no line number corresponding to the address where the
4389 inferior stopped). Since we want to skip this kind of code,
4390 we keep going until the inferior returns from this
4391 function - unless the user has asked us not to (via
4392 set step-mode) or we no longer know how to get back
4393 to the call site. */
4394 if (step_stop_if_no_debug
4395 || !frame_id_p (frame_unwind_caller_id (frame
)))
4397 /* If we have no line number and the step-stop-if-no-debug
4398 is set, we stop the step so that the user has a chance to
4399 switch in assembly mode. */
4400 ecs
->event_thread
->stop_step
= 1;
4401 print_stop_reason (END_STEPPING_RANGE
, 0);
4402 stop_stepping (ecs
);
4407 /* Set a breakpoint at callee's return address (the address
4408 at which the caller will resume). */
4409 insert_step_resume_breakpoint_at_caller (frame
);
4415 if (ecs
->event_thread
->step_range_end
== 1)
4417 /* It is stepi or nexti. We always want to stop stepping after
4420 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
4421 ecs
->event_thread
->stop_step
= 1;
4422 print_stop_reason (END_STEPPING_RANGE
, 0);
4423 stop_stepping (ecs
);
4427 if (stop_pc_sal
.line
== 0)
4429 /* We have no line number information. That means to stop
4430 stepping (does this always happen right after one instruction,
4431 when we do "s" in a function with no line numbers,
4432 or can this happen as a result of a return or longjmp?). */
4434 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
4435 ecs
->event_thread
->stop_step
= 1;
4436 print_stop_reason (END_STEPPING_RANGE
, 0);
4437 stop_stepping (ecs
);
4441 /* Look for "calls" to inlined functions, part one. If the inline
4442 frame machinery detected some skipped call sites, we have entered
4443 a new inline function. */
4445 if (frame_id_eq (get_frame_id (get_current_frame ()),
4446 ecs
->event_thread
->step_frame_id
)
4447 && inline_skipped_frames (ecs
->ptid
))
4449 struct symtab_and_line call_sal
;
4452 fprintf_unfiltered (gdb_stdlog
,
4453 "infrun: stepped into inlined function\n");
4455 find_frame_sal (get_current_frame (), &call_sal
);
4457 if (ecs
->event_thread
->step_over_calls
!= STEP_OVER_ALL
)
4459 /* For "step", we're going to stop. But if the call site
4460 for this inlined function is on the same source line as
4461 we were previously stepping, go down into the function
4462 first. Otherwise stop at the call site. */
4464 if (call_sal
.line
== ecs
->event_thread
->current_line
4465 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4466 step_into_inline_frame (ecs
->ptid
);
4468 ecs
->event_thread
->stop_step
= 1;
4469 print_stop_reason (END_STEPPING_RANGE
, 0);
4470 stop_stepping (ecs
);
4475 /* For "next", we should stop at the call site if it is on a
4476 different source line. Otherwise continue through the
4477 inlined function. */
4478 if (call_sal
.line
== ecs
->event_thread
->current_line
4479 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4483 ecs
->event_thread
->stop_step
= 1;
4484 print_stop_reason (END_STEPPING_RANGE
, 0);
4485 stop_stepping (ecs
);
4491 /* Look for "calls" to inlined functions, part two. If we are still
4492 in the same real function we were stepping through, but we have
4493 to go further up to find the exact frame ID, we are stepping
4494 through a more inlined call beyond its call site. */
4496 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
4497 && !frame_id_eq (get_frame_id (get_current_frame ()),
4498 ecs
->event_thread
->step_frame_id
)
4499 && stepped_in_from (get_current_frame (),
4500 ecs
->event_thread
->step_frame_id
))
4503 fprintf_unfiltered (gdb_stdlog
,
4504 "infrun: stepping through inlined function\n");
4506 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
4510 ecs
->event_thread
->stop_step
= 1;
4511 print_stop_reason (END_STEPPING_RANGE
, 0);
4512 stop_stepping (ecs
);
4517 if ((stop_pc
== stop_pc_sal
.pc
)
4518 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
4519 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
4521 /* We are at the start of a different line. So stop. Note that
4522 we don't stop if we step into the middle of a different line.
4523 That is said to make things like for (;;) statements work
4526 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
4527 ecs
->event_thread
->stop_step
= 1;
4528 print_stop_reason (END_STEPPING_RANGE
, 0);
4529 stop_stepping (ecs
);
4533 /* We aren't done stepping.
4535 Optimize by setting the stepping range to the line.
4536 (We might not be in the original line, but if we entered a
4537 new line in mid-statement, we continue stepping. This makes
4538 things like for(;;) statements work better.) */
4540 ecs
->event_thread
->step_range_start
= stop_pc_sal
.pc
;
4541 ecs
->event_thread
->step_range_end
= stop_pc_sal
.end
;
4542 set_step_info (frame
, stop_pc_sal
);
4545 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
4549 /* Is thread TP in the middle of single-stepping? */
4552 currently_stepping (struct thread_info
*tp
)
4554 return ((tp
->step_range_end
&& tp
->step_resume_breakpoint
== NULL
)
4555 || tp
->trap_expected
4556 || tp
->stepping_through_solib_after_catch
4557 || bpstat_should_step ());
4560 /* Returns true if any thread *but* the one passed in "data" is in the
4561 middle of stepping or of handling a "next". */
4564 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
4569 return (tp
->step_range_end
4570 || tp
->trap_expected
4571 || tp
->stepping_through_solib_after_catch
);
4574 /* Inferior has stepped into a subroutine call with source code that
4575 we should not step over. Do step to the first line of code in
4579 handle_step_into_function (struct gdbarch
*gdbarch
,
4580 struct execution_control_state
*ecs
)
4583 struct symtab_and_line stop_func_sal
, sr_sal
;
4585 s
= find_pc_symtab (stop_pc
);
4586 if (s
&& s
->language
!= language_asm
)
4587 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
4588 ecs
->stop_func_start
);
4590 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4591 /* Use the step_resume_break to step until the end of the prologue,
4592 even if that involves jumps (as it seems to on the vax under
4594 /* If the prologue ends in the middle of a source line, continue to
4595 the end of that source line (if it is still within the function).
4596 Otherwise, just go to end of prologue. */
4597 if (stop_func_sal
.end
4598 && stop_func_sal
.pc
!= ecs
->stop_func_start
4599 && stop_func_sal
.end
< ecs
->stop_func_end
)
4600 ecs
->stop_func_start
= stop_func_sal
.end
;
4602 /* Architectures which require breakpoint adjustment might not be able
4603 to place a breakpoint at the computed address. If so, the test
4604 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
4605 ecs->stop_func_start to an address at which a breakpoint may be
4606 legitimately placed.
4608 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
4609 made, GDB will enter an infinite loop when stepping through
4610 optimized code consisting of VLIW instructions which contain
4611 subinstructions corresponding to different source lines. On
4612 FR-V, it's not permitted to place a breakpoint on any but the
4613 first subinstruction of a VLIW instruction. When a breakpoint is
4614 set, GDB will adjust the breakpoint address to the beginning of
4615 the VLIW instruction. Thus, we need to make the corresponding
4616 adjustment here when computing the stop address. */
4618 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
4620 ecs
->stop_func_start
4621 = gdbarch_adjust_breakpoint_address (gdbarch
,
4622 ecs
->stop_func_start
);
4625 if (ecs
->stop_func_start
== stop_pc
)
4627 /* We are already there: stop now. */
4628 ecs
->event_thread
->stop_step
= 1;
4629 print_stop_reason (END_STEPPING_RANGE
, 0);
4630 stop_stepping (ecs
);
4635 /* Put the step-breakpoint there and go until there. */
4636 init_sal (&sr_sal
); /* initialize to zeroes */
4637 sr_sal
.pc
= ecs
->stop_func_start
;
4638 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
4639 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
4641 /* Do not specify what the fp should be when we stop since on
4642 some machines the prologue is where the new fp value is
4644 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
4646 /* And make sure stepping stops right away then. */
4647 ecs
->event_thread
->step_range_end
= ecs
->event_thread
->step_range_start
;
4652 /* Inferior has stepped backward into a subroutine call with source
4653 code that we should not step over. Do step to the beginning of the
4654 last line of code in it. */
4657 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
4658 struct execution_control_state
*ecs
)
4661 struct symtab_and_line stop_func_sal
, sr_sal
;
4663 s
= find_pc_symtab (stop_pc
);
4664 if (s
&& s
->language
!= language_asm
)
4665 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
4666 ecs
->stop_func_start
);
4668 stop_func_sal
= find_pc_line (stop_pc
, 0);
4670 /* OK, we're just going to keep stepping here. */
4671 if (stop_func_sal
.pc
== stop_pc
)
4673 /* We're there already. Just stop stepping now. */
4674 ecs
->event_thread
->stop_step
= 1;
4675 print_stop_reason (END_STEPPING_RANGE
, 0);
4676 stop_stepping (ecs
);
4680 /* Else just reset the step range and keep going.
4681 No step-resume breakpoint, they don't work for
4682 epilogues, which can have multiple entry paths. */
4683 ecs
->event_thread
->step_range_start
= stop_func_sal
.pc
;
4684 ecs
->event_thread
->step_range_end
= stop_func_sal
.end
;
4690 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
4691 This is used to both functions and to skip over code. */
4694 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
4695 struct symtab_and_line sr_sal
,
4696 struct frame_id sr_id
)
4698 /* There should never be more than one step-resume or longjmp-resume
4699 breakpoint per thread, so we should never be setting a new
4700 step_resume_breakpoint when one is already active. */
4701 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
4704 fprintf_unfiltered (gdb_stdlog
,
4705 "infrun: inserting step-resume breakpoint at %s\n",
4706 paddress (gdbarch
, sr_sal
.pc
));
4708 inferior_thread ()->step_resume_breakpoint
4709 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, bp_step_resume
);
4712 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
4713 to skip a potential signal handler.
4715 This is called with the interrupted function's frame. The signal
4716 handler, when it returns, will resume the interrupted function at
4720 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
4722 struct symtab_and_line sr_sal
;
4723 struct gdbarch
*gdbarch
;
4725 gdb_assert (return_frame
!= NULL
);
4726 init_sal (&sr_sal
); /* initialize to zeros */
4728 gdbarch
= get_frame_arch (return_frame
);
4729 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
4730 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4731 sr_sal
.pspace
= get_frame_program_space (return_frame
);
4733 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
4734 get_stack_frame_id (return_frame
));
4737 /* Similar to insert_step_resume_breakpoint_at_frame, except
4738 but a breakpoint at the previous frame's PC. This is used to
4739 skip a function after stepping into it (for "next" or if the called
4740 function has no debugging information).
4742 The current function has almost always been reached by single
4743 stepping a call or return instruction. NEXT_FRAME belongs to the
4744 current function, and the breakpoint will be set at the caller's
4747 This is a separate function rather than reusing
4748 insert_step_resume_breakpoint_at_frame in order to avoid
4749 get_prev_frame, which may stop prematurely (see the implementation
4750 of frame_unwind_caller_id for an example). */
4753 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
4755 struct symtab_and_line sr_sal
;
4756 struct gdbarch
*gdbarch
;
4758 /* We shouldn't have gotten here if we don't know where the call site
4760 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
4762 init_sal (&sr_sal
); /* initialize to zeros */
4764 gdbarch
= frame_unwind_caller_arch (next_frame
);
4765 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
4766 frame_unwind_caller_pc (next_frame
));
4767 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4768 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
4770 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
4771 frame_unwind_caller_id (next_frame
));
4774 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
4775 new breakpoint at the target of a jmp_buf. The handling of
4776 longjmp-resume uses the same mechanisms used for handling
4777 "step-resume" breakpoints. */
4780 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
4782 /* There should never be more than one step-resume or longjmp-resume
4783 breakpoint per thread, so we should never be setting a new
4784 longjmp_resume_breakpoint when one is already active. */
4785 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
4788 fprintf_unfiltered (gdb_stdlog
,
4789 "infrun: inserting longjmp-resume breakpoint at %s\n",
4790 paddress (gdbarch
, pc
));
4792 inferior_thread ()->step_resume_breakpoint
=
4793 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
4797 stop_stepping (struct execution_control_state
*ecs
)
4800 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
4802 /* Let callers know we don't want to wait for the inferior anymore. */
4803 ecs
->wait_some_more
= 0;
4806 /* This function handles various cases where we need to continue
4807 waiting for the inferior. */
4808 /* (Used to be the keep_going: label in the old wait_for_inferior) */
4811 keep_going (struct execution_control_state
*ecs
)
4813 /* Save the pc before execution, to compare with pc after stop. */
4814 ecs
->event_thread
->prev_pc
4815 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4817 /* If we did not do break;, it means we should keep running the
4818 inferior and not return to debugger. */
4820 if (ecs
->event_thread
->trap_expected
4821 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
4823 /* We took a signal (which we are supposed to pass through to
4824 the inferior, else we'd not get here) and we haven't yet
4825 gotten our trap. Simply continue. */
4826 resume (currently_stepping (ecs
->event_thread
),
4827 ecs
->event_thread
->stop_signal
);
4831 /* Either the trap was not expected, but we are continuing
4832 anyway (the user asked that this signal be passed to the
4835 The signal was SIGTRAP, e.g. it was our signal, but we
4836 decided we should resume from it.
4838 We're going to run this baby now!
4840 Note that insert_breakpoints won't try to re-insert
4841 already inserted breakpoints. Therefore, we don't
4842 care if breakpoints were already inserted, or not. */
4844 if (ecs
->event_thread
->stepping_over_breakpoint
)
4846 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
4847 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
4848 /* Since we can't do a displaced step, we have to remove
4849 the breakpoint while we step it. To keep things
4850 simple, we remove them all. */
4851 remove_breakpoints ();
4855 struct gdb_exception e
;
4856 /* Stop stepping when inserting breakpoints
4858 TRY_CATCH (e
, RETURN_MASK_ERROR
)
4860 insert_breakpoints ();
4864 stop_stepping (ecs
);
4869 ecs
->event_thread
->trap_expected
= ecs
->event_thread
->stepping_over_breakpoint
;
4871 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
4872 specifies that such a signal should be delivered to the
4875 Typically, this would occure when a user is debugging a
4876 target monitor on a simulator: the target monitor sets a
4877 breakpoint; the simulator encounters this break-point and
4878 halts the simulation handing control to GDB; GDB, noteing
4879 that the break-point isn't valid, returns control back to the
4880 simulator; the simulator then delivers the hardware
4881 equivalent of a SIGNAL_TRAP to the program being debugged. */
4883 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
4884 && !signal_program
[ecs
->event_thread
->stop_signal
])
4885 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
4887 resume (currently_stepping (ecs
->event_thread
),
4888 ecs
->event_thread
->stop_signal
);
4891 prepare_to_wait (ecs
);
4894 /* This function normally comes after a resume, before
4895 handle_inferior_event exits. It takes care of any last bits of
4896 housekeeping, and sets the all-important wait_some_more flag. */
4899 prepare_to_wait (struct execution_control_state
*ecs
)
4902 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
4904 /* This is the old end of the while loop. Let everybody know we
4905 want to wait for the inferior some more and get called again
4907 ecs
->wait_some_more
= 1;
4910 /* Print why the inferior has stopped. We always print something when
4911 the inferior exits, or receives a signal. The rest of the cases are
4912 dealt with later on in normal_stop() and print_it_typical(). Ideally
4913 there should be a call to this function from handle_inferior_event()
4914 each time stop_stepping() is called.*/
4916 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
4918 switch (stop_reason
)
4920 case END_STEPPING_RANGE
:
4921 /* We are done with a step/next/si/ni command. */
4922 /* For now print nothing. */
4923 /* Print a message only if not in the middle of doing a "step n"
4924 operation for n > 1 */
4925 if (!inferior_thread ()->step_multi
4926 || !inferior_thread ()->stop_step
)
4927 if (ui_out_is_mi_like_p (uiout
))
4930 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
4933 /* The inferior was terminated by a signal. */
4934 annotate_signalled ();
4935 if (ui_out_is_mi_like_p (uiout
))
4938 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
4939 ui_out_text (uiout
, "\nProgram terminated with signal ");
4940 annotate_signal_name ();
4941 ui_out_field_string (uiout
, "signal-name",
4942 target_signal_to_name (stop_info
));
4943 annotate_signal_name_end ();
4944 ui_out_text (uiout
, ", ");
4945 annotate_signal_string ();
4946 ui_out_field_string (uiout
, "signal-meaning",
4947 target_signal_to_string (stop_info
));
4948 annotate_signal_string_end ();
4949 ui_out_text (uiout
, ".\n");
4950 ui_out_text (uiout
, "The program no longer exists.\n");
4953 /* The inferior program is finished. */
4954 annotate_exited (stop_info
);
4957 if (ui_out_is_mi_like_p (uiout
))
4958 ui_out_field_string (uiout
, "reason",
4959 async_reason_lookup (EXEC_ASYNC_EXITED
));
4960 ui_out_text (uiout
, "\nProgram exited with code ");
4961 ui_out_field_fmt (uiout
, "exit-code", "0%o",
4962 (unsigned int) stop_info
);
4963 ui_out_text (uiout
, ".\n");
4967 if (ui_out_is_mi_like_p (uiout
))
4970 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
4971 ui_out_text (uiout
, "\nProgram exited normally.\n");
4973 /* Support the --return-child-result option. */
4974 return_child_result_value
= stop_info
;
4976 case SIGNAL_RECEIVED
:
4977 /* Signal received. The signal table tells us to print about
4981 if (stop_info
== TARGET_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
4983 struct thread_info
*t
= inferior_thread ();
4985 ui_out_text (uiout
, "\n[");
4986 ui_out_field_string (uiout
, "thread-name",
4987 target_pid_to_str (t
->ptid
));
4988 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
4989 ui_out_text (uiout
, " stopped");
4993 ui_out_text (uiout
, "\nProgram received signal ");
4994 annotate_signal_name ();
4995 if (ui_out_is_mi_like_p (uiout
))
4997 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
4998 ui_out_field_string (uiout
, "signal-name",
4999 target_signal_to_name (stop_info
));
5000 annotate_signal_name_end ();
5001 ui_out_text (uiout
, ", ");
5002 annotate_signal_string ();
5003 ui_out_field_string (uiout
, "signal-meaning",
5004 target_signal_to_string (stop_info
));
5005 annotate_signal_string_end ();
5007 ui_out_text (uiout
, ".\n");
5010 /* Reverse execution: target ran out of history info. */
5011 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
5014 internal_error (__FILE__
, __LINE__
,
5015 _("print_stop_reason: unrecognized enum value"));
5021 /* Here to return control to GDB when the inferior stops for real.
5022 Print appropriate messages, remove breakpoints, give terminal our modes.
5024 STOP_PRINT_FRAME nonzero means print the executing frame
5025 (pc, function, args, file, line number and line text).
5026 BREAKPOINTS_FAILED nonzero means stop was due to error
5027 attempting to insert breakpoints. */
5032 struct target_waitstatus last
;
5034 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
5036 get_last_target_status (&last_ptid
, &last
);
5038 /* If an exception is thrown from this point on, make sure to
5039 propagate GDB's knowledge of the executing state to the
5040 frontend/user running state. A QUIT is an easy exception to see
5041 here, so do this before any filtered output. */
5043 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
5044 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5045 && last
.kind
!= TARGET_WAITKIND_EXITED
)
5046 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
5048 /* In non-stop mode, we don't want GDB to switch threads behind the
5049 user's back, to avoid races where the user is typing a command to
5050 apply to thread x, but GDB switches to thread y before the user
5051 finishes entering the command. */
5053 /* As with the notification of thread events, we want to delay
5054 notifying the user that we've switched thread context until
5055 the inferior actually stops.
5057 There's no point in saying anything if the inferior has exited.
5058 Note that SIGNALLED here means "exited with a signal", not
5059 "received a signal". */
5061 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
5062 && target_has_execution
5063 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5064 && last
.kind
!= TARGET_WAITKIND_EXITED
)
5066 target_terminal_ours_for_output ();
5067 printf_filtered (_("[Switching to %s]\n"),
5068 target_pid_to_str (inferior_ptid
));
5069 annotate_thread_changed ();
5070 previous_inferior_ptid
= inferior_ptid
;
5073 if (!breakpoints_always_inserted_mode () && target_has_execution
)
5075 if (remove_breakpoints ())
5077 target_terminal_ours_for_output ();
5078 printf_filtered (_("\
5079 Cannot remove breakpoints because program is no longer writable.\n\
5080 Further execution is probably impossible.\n"));
5084 /* If an auto-display called a function and that got a signal,
5085 delete that auto-display to avoid an infinite recursion. */
5087 if (stopped_by_random_signal
)
5088 disable_current_display ();
5090 /* Don't print a message if in the middle of doing a "step n"
5091 operation for n > 1 */
5092 if (target_has_execution
5093 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5094 && last
.kind
!= TARGET_WAITKIND_EXITED
5095 && inferior_thread ()->step_multi
5096 && inferior_thread ()->stop_step
)
5099 target_terminal_ours ();
5101 /* Set the current source location. This will also happen if we
5102 display the frame below, but the current SAL will be incorrect
5103 during a user hook-stop function. */
5104 if (has_stack_frames () && !stop_stack_dummy
)
5105 set_current_sal_from_frame (get_current_frame (), 1);
5107 /* Let the user/frontend see the threads as stopped. */
5108 do_cleanups (old_chain
);
5110 /* Look up the hook_stop and run it (CLI internally handles problem
5111 of stop_command's pre-hook not existing). */
5113 catch_errors (hook_stop_stub
, stop_command
,
5114 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
5116 if (!has_stack_frames ())
5119 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
5120 || last
.kind
== TARGET_WAITKIND_EXITED
)
5123 /* Select innermost stack frame - i.e., current frame is frame 0,
5124 and current location is based on that.
5125 Don't do this on return from a stack dummy routine,
5126 or if the program has exited. */
5128 if (!stop_stack_dummy
)
5130 select_frame (get_current_frame ());
5132 /* Print current location without a level number, if
5133 we have changed functions or hit a breakpoint.
5134 Print source line if we have one.
5135 bpstat_print() contains the logic deciding in detail
5136 what to print, based on the event(s) that just occurred. */
5138 /* If --batch-silent is enabled then there's no need to print the current
5139 source location, and to try risks causing an error message about
5140 missing source files. */
5141 if (stop_print_frame
&& !batch_silent
)
5145 int do_frame_printing
= 1;
5146 struct thread_info
*tp
= inferior_thread ();
5148 bpstat_ret
= bpstat_print (tp
->stop_bpstat
);
5152 /* If we had hit a shared library event breakpoint,
5153 bpstat_print would print out this message. If we hit
5154 an OS-level shared library event, do the same
5156 if (last
.kind
== TARGET_WAITKIND_LOADED
)
5158 printf_filtered (_("Stopped due to shared library event\n"));
5159 source_flag
= SRC_LINE
; /* something bogus */
5160 do_frame_printing
= 0;
5164 /* FIXME: cagney/2002-12-01: Given that a frame ID does
5165 (or should) carry around the function and does (or
5166 should) use that when doing a frame comparison. */
5168 && frame_id_eq (tp
->step_frame_id
,
5169 get_frame_id (get_current_frame ()))
5170 && step_start_function
== find_pc_function (stop_pc
))
5171 source_flag
= SRC_LINE
; /* finished step, just print source line */
5173 source_flag
= SRC_AND_LOC
; /* print location and source line */
5175 case PRINT_SRC_AND_LOC
:
5176 source_flag
= SRC_AND_LOC
; /* print location and source line */
5178 case PRINT_SRC_ONLY
:
5179 source_flag
= SRC_LINE
;
5182 source_flag
= SRC_LINE
; /* something bogus */
5183 do_frame_printing
= 0;
5186 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
5189 /* The behavior of this routine with respect to the source
5191 SRC_LINE: Print only source line
5192 LOCATION: Print only location
5193 SRC_AND_LOC: Print location and source line */
5194 if (do_frame_printing
)
5195 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
5197 /* Display the auto-display expressions. */
5202 /* Save the function value return registers, if we care.
5203 We might be about to restore their previous contents. */
5204 if (inferior_thread ()->proceed_to_finish
)
5206 /* This should not be necessary. */
5208 regcache_xfree (stop_registers
);
5210 /* NB: The copy goes through to the target picking up the value of
5211 all the registers. */
5212 stop_registers
= regcache_dup (get_current_regcache ());
5215 if (stop_stack_dummy
)
5217 /* Pop the empty frame that contains the stack dummy.
5218 This also restores inferior state prior to the call
5219 (struct inferior_thread_state). */
5220 struct frame_info
*frame
= get_current_frame ();
5221 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
5223 /* frame_pop() calls reinit_frame_cache as the last thing it does
5224 which means there's currently no selected frame. We don't need
5225 to re-establish a selected frame if the dummy call returns normally,
5226 that will be done by restore_inferior_status. However, we do have
5227 to handle the case where the dummy call is returning after being
5228 stopped (e.g. the dummy call previously hit a breakpoint). We
5229 can't know which case we have so just always re-establish a
5230 selected frame here. */
5231 select_frame (get_current_frame ());
5235 annotate_stopped ();
5237 /* Suppress the stop observer if we're in the middle of:
5239 - a step n (n > 1), as there still more steps to be done.
5241 - a "finish" command, as the observer will be called in
5242 finish_command_continuation, so it can include the inferior
5243 function's return value.
5245 - calling an inferior function, as we pretend we inferior didn't
5246 run at all. The return value of the call is handled by the
5247 expression evaluator, through call_function_by_hand. */
5249 if (!target_has_execution
5250 || last
.kind
== TARGET_WAITKIND_SIGNALLED
5251 || last
.kind
== TARGET_WAITKIND_EXITED
5252 || (!inferior_thread ()->step_multi
5253 && !(inferior_thread ()->stop_bpstat
5254 && inferior_thread ()->proceed_to_finish
)
5255 && !inferior_thread ()->in_infcall
))
5257 if (!ptid_equal (inferior_ptid
, null_ptid
))
5258 observer_notify_normal_stop (inferior_thread ()->stop_bpstat
,
5261 observer_notify_normal_stop (NULL
, stop_print_frame
);
5264 if (target_has_execution
)
5266 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5267 && last
.kind
!= TARGET_WAITKIND_EXITED
)
5268 /* Delete the breakpoint we stopped at, if it wants to be deleted.
5269 Delete any breakpoint that is to be deleted at the next stop. */
5270 breakpoint_auto_delete (inferior_thread ()->stop_bpstat
);
5273 /* Try to get rid of automatically added inferiors that are no
5274 longer needed. Keeping those around slows down things linearly.
5275 Note that this never removes the current inferior. */
5280 hook_stop_stub (void *cmd
)
5282 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
5287 signal_stop_state (int signo
)
5289 return signal_stop
[signo
];
5293 signal_print_state (int signo
)
5295 return signal_print
[signo
];
5299 signal_pass_state (int signo
)
5301 return signal_program
[signo
];
5305 signal_stop_update (int signo
, int state
)
5307 int ret
= signal_stop
[signo
];
5308 signal_stop
[signo
] = state
;
5313 signal_print_update (int signo
, int state
)
5315 int ret
= signal_print
[signo
];
5316 signal_print
[signo
] = state
;
5321 signal_pass_update (int signo
, int state
)
5323 int ret
= signal_program
[signo
];
5324 signal_program
[signo
] = state
;
5329 sig_print_header (void)
5331 printf_filtered (_("\
5332 Signal Stop\tPrint\tPass to program\tDescription\n"));
5336 sig_print_info (enum target_signal oursig
)
5338 const char *name
= target_signal_to_name (oursig
);
5339 int name_padding
= 13 - strlen (name
);
5341 if (name_padding
<= 0)
5344 printf_filtered ("%s", name
);
5345 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
5346 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
5347 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
5348 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
5349 printf_filtered ("%s\n", target_signal_to_string (oursig
));
5352 /* Specify how various signals in the inferior should be handled. */
5355 handle_command (char *args
, int from_tty
)
5358 int digits
, wordlen
;
5359 int sigfirst
, signum
, siglast
;
5360 enum target_signal oursig
;
5363 unsigned char *sigs
;
5364 struct cleanup
*old_chain
;
5368 error_no_arg (_("signal to handle"));
5371 /* Allocate and zero an array of flags for which signals to handle. */
5373 nsigs
= (int) TARGET_SIGNAL_LAST
;
5374 sigs
= (unsigned char *) alloca (nsigs
);
5375 memset (sigs
, 0, nsigs
);
5377 /* Break the command line up into args. */
5379 argv
= gdb_buildargv (args
);
5380 old_chain
= make_cleanup_freeargv (argv
);
5382 /* Walk through the args, looking for signal oursigs, signal names, and
5383 actions. Signal numbers and signal names may be interspersed with
5384 actions, with the actions being performed for all signals cumulatively
5385 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
5387 while (*argv
!= NULL
)
5389 wordlen
= strlen (*argv
);
5390 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
5394 sigfirst
= siglast
= -1;
5396 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
5398 /* Apply action to all signals except those used by the
5399 debugger. Silently skip those. */
5402 siglast
= nsigs
- 1;
5404 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
5406 SET_SIGS (nsigs
, sigs
, signal_stop
);
5407 SET_SIGS (nsigs
, sigs
, signal_print
);
5409 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
5411 UNSET_SIGS (nsigs
, sigs
, signal_program
);
5413 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
5415 SET_SIGS (nsigs
, sigs
, signal_print
);
5417 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
5419 SET_SIGS (nsigs
, sigs
, signal_program
);
5421 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
5423 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
5425 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
5427 SET_SIGS (nsigs
, sigs
, signal_program
);
5429 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
5431 UNSET_SIGS (nsigs
, sigs
, signal_print
);
5432 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
5434 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
5436 UNSET_SIGS (nsigs
, sigs
, signal_program
);
5438 else if (digits
> 0)
5440 /* It is numeric. The numeric signal refers to our own
5441 internal signal numbering from target.h, not to host/target
5442 signal number. This is a feature; users really should be
5443 using symbolic names anyway, and the common ones like
5444 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
5446 sigfirst
= siglast
= (int)
5447 target_signal_from_command (atoi (*argv
));
5448 if ((*argv
)[digits
] == '-')
5451 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
5453 if (sigfirst
> siglast
)
5455 /* Bet he didn't figure we'd think of this case... */
5463 oursig
= target_signal_from_name (*argv
);
5464 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
5466 sigfirst
= siglast
= (int) oursig
;
5470 /* Not a number and not a recognized flag word => complain. */
5471 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
5475 /* If any signal numbers or symbol names were found, set flags for
5476 which signals to apply actions to. */
5478 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
5480 switch ((enum target_signal
) signum
)
5482 case TARGET_SIGNAL_TRAP
:
5483 case TARGET_SIGNAL_INT
:
5484 if (!allsigs
&& !sigs
[signum
])
5486 if (query (_("%s is used by the debugger.\n\
5487 Are you sure you want to change it? "), target_signal_to_name ((enum target_signal
) signum
)))
5493 printf_unfiltered (_("Not confirmed, unchanged.\n"));
5494 gdb_flush (gdb_stdout
);
5498 case TARGET_SIGNAL_0
:
5499 case TARGET_SIGNAL_DEFAULT
:
5500 case TARGET_SIGNAL_UNKNOWN
:
5501 /* Make sure that "all" doesn't print these. */
5512 for (signum
= 0; signum
< nsigs
; signum
++)
5515 target_notice_signals (inferior_ptid
);
5519 /* Show the results. */
5520 sig_print_header ();
5521 for (; signum
< nsigs
; signum
++)
5523 sig_print_info (signum
);
5529 do_cleanups (old_chain
);
5533 xdb_handle_command (char *args
, int from_tty
)
5536 struct cleanup
*old_chain
;
5539 error_no_arg (_("xdb command"));
5541 /* Break the command line up into args. */
5543 argv
= gdb_buildargv (args
);
5544 old_chain
= make_cleanup_freeargv (argv
);
5545 if (argv
[1] != (char *) NULL
)
5550 bufLen
= strlen (argv
[0]) + 20;
5551 argBuf
= (char *) xmalloc (bufLen
);
5555 enum target_signal oursig
;
5557 oursig
= target_signal_from_name (argv
[0]);
5558 memset (argBuf
, 0, bufLen
);
5559 if (strcmp (argv
[1], "Q") == 0)
5560 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
5563 if (strcmp (argv
[1], "s") == 0)
5565 if (!signal_stop
[oursig
])
5566 sprintf (argBuf
, "%s %s", argv
[0], "stop");
5568 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
5570 else if (strcmp (argv
[1], "i") == 0)
5572 if (!signal_program
[oursig
])
5573 sprintf (argBuf
, "%s %s", argv
[0], "pass");
5575 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
5577 else if (strcmp (argv
[1], "r") == 0)
5579 if (!signal_print
[oursig
])
5580 sprintf (argBuf
, "%s %s", argv
[0], "print");
5582 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
5588 handle_command (argBuf
, from_tty
);
5590 printf_filtered (_("Invalid signal handling flag.\n"));
5595 do_cleanups (old_chain
);
5598 /* Print current contents of the tables set by the handle command.
5599 It is possible we should just be printing signals actually used
5600 by the current target (but for things to work right when switching
5601 targets, all signals should be in the signal tables). */
5604 signals_info (char *signum_exp
, int from_tty
)
5606 enum target_signal oursig
;
5607 sig_print_header ();
5611 /* First see if this is a symbol name. */
5612 oursig
= target_signal_from_name (signum_exp
);
5613 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
5615 /* No, try numeric. */
5617 target_signal_from_command (parse_and_eval_long (signum_exp
));
5619 sig_print_info (oursig
);
5623 printf_filtered ("\n");
5624 /* These ugly casts brought to you by the native VAX compiler. */
5625 for (oursig
= TARGET_SIGNAL_FIRST
;
5626 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
5627 oursig
= (enum target_signal
) ((int) oursig
+ 1))
5631 if (oursig
!= TARGET_SIGNAL_UNKNOWN
5632 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
5633 sig_print_info (oursig
);
5636 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
5639 /* The $_siginfo convenience variable is a bit special. We don't know
5640 for sure the type of the value until we actually have a chance to
5641 fetch the data. The type can change depending on gdbarch, so it it
5642 also dependent on which thread you have selected.
5644 1. making $_siginfo be an internalvar that creates a new value on
5647 2. making the value of $_siginfo be an lval_computed value. */
5649 /* This function implements the lval_computed support for reading a
5653 siginfo_value_read (struct value
*v
)
5655 LONGEST transferred
;
5658 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
5660 value_contents_all_raw (v
),
5662 TYPE_LENGTH (value_type (v
)));
5664 if (transferred
!= TYPE_LENGTH (value_type (v
)))
5665 error (_("Unable to read siginfo"));
5668 /* This function implements the lval_computed support for writing a
5672 siginfo_value_write (struct value
*v
, struct value
*fromval
)
5674 LONGEST transferred
;
5676 transferred
= target_write (¤t_target
,
5677 TARGET_OBJECT_SIGNAL_INFO
,
5679 value_contents_all_raw (fromval
),
5681 TYPE_LENGTH (value_type (fromval
)));
5683 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
5684 error (_("Unable to write siginfo"));
5687 static struct lval_funcs siginfo_value_funcs
=
5693 /* Return a new value with the correct type for the siginfo object of
5694 the current thread using architecture GDBARCH. Return a void value
5695 if there's no object available. */
5697 static struct value
*
5698 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
)
5700 if (target_has_stack
5701 && !ptid_equal (inferior_ptid
, null_ptid
)
5702 && gdbarch_get_siginfo_type_p (gdbarch
))
5704 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
5705 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
5708 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
5712 /* Inferior thread state.
5713 These are details related to the inferior itself, and don't include
5714 things like what frame the user had selected or what gdb was doing
5715 with the target at the time.
5716 For inferior function calls these are things we want to restore
5717 regardless of whether the function call successfully completes
5718 or the dummy frame has to be manually popped. */
5720 struct inferior_thread_state
5722 enum target_signal stop_signal
;
5724 struct regcache
*registers
;
5727 struct inferior_thread_state
*
5728 save_inferior_thread_state (void)
5730 struct inferior_thread_state
*inf_state
= XMALLOC (struct inferior_thread_state
);
5731 struct thread_info
*tp
= inferior_thread ();
5733 inf_state
->stop_signal
= tp
->stop_signal
;
5734 inf_state
->stop_pc
= stop_pc
;
5736 inf_state
->registers
= regcache_dup (get_current_regcache ());
5741 /* Restore inferior session state to INF_STATE. */
5744 restore_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5746 struct thread_info
*tp
= inferior_thread ();
5748 tp
->stop_signal
= inf_state
->stop_signal
;
5749 stop_pc
= inf_state
->stop_pc
;
5751 /* The inferior can be gone if the user types "print exit(0)"
5752 (and perhaps other times). */
5753 if (target_has_execution
)
5754 /* NB: The register write goes through to the target. */
5755 regcache_cpy (get_current_regcache (), inf_state
->registers
);
5756 regcache_xfree (inf_state
->registers
);
5761 do_restore_inferior_thread_state_cleanup (void *state
)
5763 restore_inferior_thread_state (state
);
5767 make_cleanup_restore_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5769 return make_cleanup (do_restore_inferior_thread_state_cleanup
, inf_state
);
5773 discard_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5775 regcache_xfree (inf_state
->registers
);
5780 get_inferior_thread_state_regcache (struct inferior_thread_state
*inf_state
)
5782 return inf_state
->registers
;
5785 /* Session related state for inferior function calls.
5786 These are the additional bits of state that need to be restored
5787 when an inferior function call successfully completes. */
5789 struct inferior_status
5793 int stop_stack_dummy
;
5794 int stopped_by_random_signal
;
5795 int stepping_over_breakpoint
;
5796 CORE_ADDR step_range_start
;
5797 CORE_ADDR step_range_end
;
5798 struct frame_id step_frame_id
;
5799 struct frame_id step_stack_frame_id
;
5800 enum step_over_calls_kind step_over_calls
;
5801 CORE_ADDR step_resume_break_address
;
5802 int stop_after_trap
;
5805 /* ID if the selected frame when the inferior function call was made. */
5806 struct frame_id selected_frame_id
;
5808 int proceed_to_finish
;
5812 /* Save all of the information associated with the inferior<==>gdb
5815 struct inferior_status
*
5816 save_inferior_status (void)
5818 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
5819 struct thread_info
*tp
= inferior_thread ();
5820 struct inferior
*inf
= current_inferior ();
5822 inf_status
->stop_step
= tp
->stop_step
;
5823 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
5824 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
5825 inf_status
->stepping_over_breakpoint
= tp
->trap_expected
;
5826 inf_status
->step_range_start
= tp
->step_range_start
;
5827 inf_status
->step_range_end
= tp
->step_range_end
;
5828 inf_status
->step_frame_id
= tp
->step_frame_id
;
5829 inf_status
->step_stack_frame_id
= tp
->step_stack_frame_id
;
5830 inf_status
->step_over_calls
= tp
->step_over_calls
;
5831 inf_status
->stop_after_trap
= stop_after_trap
;
5832 inf_status
->stop_soon
= inf
->stop_soon
;
5833 /* Save original bpstat chain here; replace it with copy of chain.
5834 If caller's caller is walking the chain, they'll be happier if we
5835 hand them back the original chain when restore_inferior_status is
5837 inf_status
->stop_bpstat
= tp
->stop_bpstat
;
5838 tp
->stop_bpstat
= bpstat_copy (tp
->stop_bpstat
);
5839 inf_status
->proceed_to_finish
= tp
->proceed_to_finish
;
5840 inf_status
->in_infcall
= tp
->in_infcall
;
5842 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
5848 restore_selected_frame (void *args
)
5850 struct frame_id
*fid
= (struct frame_id
*) args
;
5851 struct frame_info
*frame
;
5853 frame
= frame_find_by_id (*fid
);
5855 /* If inf_status->selected_frame_id is NULL, there was no previously
5859 warning (_("Unable to restore previously selected frame."));
5863 select_frame (frame
);
5868 /* Restore inferior session state to INF_STATUS. */
5871 restore_inferior_status (struct inferior_status
*inf_status
)
5873 struct thread_info
*tp
= inferior_thread ();
5874 struct inferior
*inf
= current_inferior ();
5876 tp
->stop_step
= inf_status
->stop_step
;
5877 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
5878 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
5879 tp
->trap_expected
= inf_status
->stepping_over_breakpoint
;
5880 tp
->step_range_start
= inf_status
->step_range_start
;
5881 tp
->step_range_end
= inf_status
->step_range_end
;
5882 tp
->step_frame_id
= inf_status
->step_frame_id
;
5883 tp
->step_stack_frame_id
= inf_status
->step_stack_frame_id
;
5884 tp
->step_over_calls
= inf_status
->step_over_calls
;
5885 stop_after_trap
= inf_status
->stop_after_trap
;
5886 inf
->stop_soon
= inf_status
->stop_soon
;
5887 bpstat_clear (&tp
->stop_bpstat
);
5888 tp
->stop_bpstat
= inf_status
->stop_bpstat
;
5889 inf_status
->stop_bpstat
= NULL
;
5890 tp
->proceed_to_finish
= inf_status
->proceed_to_finish
;
5891 tp
->in_infcall
= inf_status
->in_infcall
;
5893 if (target_has_stack
)
5895 /* The point of catch_errors is that if the stack is clobbered,
5896 walking the stack might encounter a garbage pointer and
5897 error() trying to dereference it. */
5899 (restore_selected_frame
, &inf_status
->selected_frame_id
,
5900 "Unable to restore previously selected frame:\n",
5901 RETURN_MASK_ERROR
) == 0)
5902 /* Error in restoring the selected frame. Select the innermost
5904 select_frame (get_current_frame ());
5911 do_restore_inferior_status_cleanup (void *sts
)
5913 restore_inferior_status (sts
);
5917 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
5919 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
5923 discard_inferior_status (struct inferior_status
*inf_status
)
5925 /* See save_inferior_status for info on stop_bpstat. */
5926 bpstat_clear (&inf_status
->stop_bpstat
);
5931 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
5933 struct target_waitstatus last
;
5936 get_last_target_status (&last_ptid
, &last
);
5938 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
5941 if (!ptid_equal (last_ptid
, pid
))
5944 *child_pid
= last
.value
.related_pid
;
5949 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
5951 struct target_waitstatus last
;
5954 get_last_target_status (&last_ptid
, &last
);
5956 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
5959 if (!ptid_equal (last_ptid
, pid
))
5962 *child_pid
= last
.value
.related_pid
;
5967 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
5969 struct target_waitstatus last
;
5972 get_last_target_status (&last_ptid
, &last
);
5974 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
5977 if (!ptid_equal (last_ptid
, pid
))
5980 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
5985 inferior_has_called_syscall (ptid_t pid
, int *syscall_number
)
5987 struct target_waitstatus last
;
5990 get_last_target_status (&last_ptid
, &last
);
5992 if (last
.kind
!= TARGET_WAITKIND_SYSCALL_ENTRY
&&
5993 last
.kind
!= TARGET_WAITKIND_SYSCALL_RETURN
)
5996 if (!ptid_equal (last_ptid
, pid
))
5999 *syscall_number
= last
.value
.syscall_number
;
6003 /* Oft used ptids */
6005 ptid_t minus_one_ptid
;
6007 /* Create a ptid given the necessary PID, LWP, and TID components. */
6010 ptid_build (int pid
, long lwp
, long tid
)
6020 /* Create a ptid from just a pid. */
6023 pid_to_ptid (int pid
)
6025 return ptid_build (pid
, 0, 0);
6028 /* Fetch the pid (process id) component from a ptid. */
6031 ptid_get_pid (ptid_t ptid
)
6036 /* Fetch the lwp (lightweight process) component from a ptid. */
6039 ptid_get_lwp (ptid_t ptid
)
6044 /* Fetch the tid (thread id) component from a ptid. */
6047 ptid_get_tid (ptid_t ptid
)
6052 /* ptid_equal() is used to test equality of two ptids. */
6055 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
6057 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
6058 && ptid1
.tid
== ptid2
.tid
);
6061 /* Returns true if PTID represents a process. */
6064 ptid_is_pid (ptid_t ptid
)
6066 if (ptid_equal (minus_one_ptid
, ptid
))
6068 if (ptid_equal (null_ptid
, ptid
))
6071 return (ptid_get_lwp (ptid
) == 0 && ptid_get_tid (ptid
) == 0);
6074 /* restore_inferior_ptid() will be used by the cleanup machinery
6075 to restore the inferior_ptid value saved in a call to
6076 save_inferior_ptid(). */
6079 restore_inferior_ptid (void *arg
)
6081 ptid_t
*saved_ptid_ptr
= arg
;
6082 inferior_ptid
= *saved_ptid_ptr
;
6086 /* Save the value of inferior_ptid so that it may be restored by a
6087 later call to do_cleanups(). Returns the struct cleanup pointer
6088 needed for later doing the cleanup. */
6091 save_inferior_ptid (void)
6093 ptid_t
*saved_ptid_ptr
;
6095 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
6096 *saved_ptid_ptr
= inferior_ptid
;
6097 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
6101 /* User interface for reverse debugging:
6102 Set exec-direction / show exec-direction commands
6103 (returns error unless target implements to_set_exec_direction method). */
6105 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
6106 static const char exec_forward
[] = "forward";
6107 static const char exec_reverse
[] = "reverse";
6108 static const char *exec_direction
= exec_forward
;
6109 static const char *exec_direction_names
[] = {
6116 set_exec_direction_func (char *args
, int from_tty
,
6117 struct cmd_list_element
*cmd
)
6119 if (target_can_execute_reverse
)
6121 if (!strcmp (exec_direction
, exec_forward
))
6122 execution_direction
= EXEC_FORWARD
;
6123 else if (!strcmp (exec_direction
, exec_reverse
))
6124 execution_direction
= EXEC_REVERSE
;
6129 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
6130 struct cmd_list_element
*cmd
, const char *value
)
6132 switch (execution_direction
) {
6134 fprintf_filtered (out
, _("Forward.\n"));
6137 fprintf_filtered (out
, _("Reverse.\n"));
6141 fprintf_filtered (out
,
6142 _("Forward (target `%s' does not support exec-direction).\n"),
6148 /* User interface for non-stop mode. */
6151 static int non_stop_1
= 0;
6154 set_non_stop (char *args
, int from_tty
,
6155 struct cmd_list_element
*c
)
6157 if (target_has_execution
)
6159 non_stop_1
= non_stop
;
6160 error (_("Cannot change this setting while the inferior is running."));
6163 non_stop
= non_stop_1
;
6167 show_non_stop (struct ui_file
*file
, int from_tty
,
6168 struct cmd_list_element
*c
, const char *value
)
6170 fprintf_filtered (file
,
6171 _("Controlling the inferior in non-stop mode is %s.\n"),
6176 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
6177 struct cmd_list_element
*c
, const char *value
)
6179 fprintf_filtered (file
, _("\
6180 Resuming the execution of threads of all processes is %s.\n"), value
);
6184 _initialize_infrun (void)
6188 struct cmd_list_element
*c
;
6190 add_info ("signals", signals_info
, _("\
6191 What debugger does when program gets various signals.\n\
6192 Specify a signal as argument to print info on that signal only."));
6193 add_info_alias ("handle", "signals", 0);
6195 add_com ("handle", class_run
, handle_command
, _("\
6196 Specify how to handle a signal.\n\
6197 Args are signals and actions to apply to those signals.\n\
6198 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
6199 from 1-15 are allowed for compatibility with old versions of GDB.\n\
6200 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
6201 The special arg \"all\" is recognized to mean all signals except those\n\
6202 used by the debugger, typically SIGTRAP and SIGINT.\n\
6203 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
6204 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
6205 Stop means reenter debugger if this signal happens (implies print).\n\
6206 Print means print a message if this signal happens.\n\
6207 Pass means let program see this signal; otherwise program doesn't know.\n\
6208 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
6209 Pass and Stop may be combined."));
6212 add_com ("lz", class_info
, signals_info
, _("\
6213 What debugger does when program gets various signals.\n\
6214 Specify a signal as argument to print info on that signal only."));
6215 add_com ("z", class_run
, xdb_handle_command
, _("\
6216 Specify how to handle a signal.\n\
6217 Args are signals and actions to apply to those signals.\n\
6218 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
6219 from 1-15 are allowed for compatibility with old versions of GDB.\n\
6220 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
6221 The special arg \"all\" is recognized to mean all signals except those\n\
6222 used by the debugger, typically SIGTRAP and SIGINT.\n\
6223 Recognized actions include \"s\" (toggles between stop and nostop), \n\
6224 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
6225 nopass), \"Q\" (noprint)\n\
6226 Stop means reenter debugger if this signal happens (implies print).\n\
6227 Print means print a message if this signal happens.\n\
6228 Pass means let program see this signal; otherwise program doesn't know.\n\
6229 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
6230 Pass and Stop may be combined."));
6234 stop_command
= add_cmd ("stop", class_obscure
,
6235 not_just_help_class_command
, _("\
6236 There is no `stop' command, but you can set a hook on `stop'.\n\
6237 This allows you to set a list of commands to be run each time execution\n\
6238 of the program stops."), &cmdlist
);
6240 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
6241 Set inferior debugging."), _("\
6242 Show inferior debugging."), _("\
6243 When non-zero, inferior specific debugging is enabled."),
6246 &setdebuglist
, &showdebuglist
);
6248 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
6249 Set displaced stepping debugging."), _("\
6250 Show displaced stepping debugging."), _("\
6251 When non-zero, displaced stepping specific debugging is enabled."),
6253 show_debug_displaced
,
6254 &setdebuglist
, &showdebuglist
);
6256 add_setshow_boolean_cmd ("non-stop", no_class
,
6258 Set whether gdb controls the inferior in non-stop mode."), _("\
6259 Show whether gdb controls the inferior in non-stop mode."), _("\
6260 When debugging a multi-threaded program and this setting is\n\
6261 off (the default, also called all-stop mode), when one thread stops\n\
6262 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
6263 all other threads in the program while you interact with the thread of\n\
6264 interest. When you continue or step a thread, you can allow the other\n\
6265 threads to run, or have them remain stopped, but while you inspect any\n\
6266 thread's state, all threads stop.\n\
6268 In non-stop mode, when one thread stops, other threads can continue\n\
6269 to run freely. You'll be able to step each thread independently,\n\
6270 leave it stopped or free to run as needed."),
6276 numsigs
= (int) TARGET_SIGNAL_LAST
;
6277 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
6278 signal_print
= (unsigned char *)
6279 xmalloc (sizeof (signal_print
[0]) * numsigs
);
6280 signal_program
= (unsigned char *)
6281 xmalloc (sizeof (signal_program
[0]) * numsigs
);
6282 for (i
= 0; i
< numsigs
; i
++)
6285 signal_print
[i
] = 1;
6286 signal_program
[i
] = 1;
6289 /* Signals caused by debugger's own actions
6290 should not be given to the program afterwards. */
6291 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
6292 signal_program
[TARGET_SIGNAL_INT
] = 0;
6294 /* Signals that are not errors should not normally enter the debugger. */
6295 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
6296 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
6297 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
6298 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
6299 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
6300 signal_print
[TARGET_SIGNAL_PROF
] = 0;
6301 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
6302 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
6303 signal_stop
[TARGET_SIGNAL_IO
] = 0;
6304 signal_print
[TARGET_SIGNAL_IO
] = 0;
6305 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
6306 signal_print
[TARGET_SIGNAL_POLL
] = 0;
6307 signal_stop
[TARGET_SIGNAL_URG
] = 0;
6308 signal_print
[TARGET_SIGNAL_URG
] = 0;
6309 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
6310 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
6312 /* These signals are used internally by user-level thread
6313 implementations. (See signal(5) on Solaris.) Like the above
6314 signals, a healthy program receives and handles them as part of
6315 its normal operation. */
6316 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
6317 signal_print
[TARGET_SIGNAL_LWP
] = 0;
6318 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
6319 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
6320 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
6321 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
6323 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
6324 &stop_on_solib_events
, _("\
6325 Set stopping for shared library events."), _("\
6326 Show stopping for shared library events."), _("\
6327 If nonzero, gdb will give control to the user when the dynamic linker\n\
6328 notifies gdb of shared library events. The most common event of interest\n\
6329 to the user would be loading/unloading of a new library."),
6331 show_stop_on_solib_events
,
6332 &setlist
, &showlist
);
6334 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
6335 follow_fork_mode_kind_names
,
6336 &follow_fork_mode_string
, _("\
6337 Set debugger response to a program call of fork or vfork."), _("\
6338 Show debugger response to a program call of fork or vfork."), _("\
6339 A fork or vfork creates a new process. follow-fork-mode can be:\n\
6340 parent - the original process is debugged after a fork\n\
6341 child - the new process is debugged after a fork\n\
6342 The unfollowed process will continue to run.\n\
6343 By default, the debugger will follow the parent process."),
6345 show_follow_fork_mode_string
,
6346 &setlist
, &showlist
);
6348 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
6349 follow_exec_mode_names
,
6350 &follow_exec_mode_string
, _("\
6351 Set debugger response to a program call of exec."), _("\
6352 Show debugger response to a program call of exec."), _("\
6353 An exec call replaces the program image of a process.\n\
6355 follow-exec-mode can be:\n\
6357 new - the debugger creates a new inferior and rebinds the process \n\
6358 to this new inferior. The program the process was running before\n\
6359 the exec call can be restarted afterwards by restarting the original\n\
6362 same - the debugger keeps the process bound to the same inferior.\n\
6363 The new executable image replaces the previous executable loaded in\n\
6364 the inferior. Restarting the inferior after the exec call restarts\n\
6365 the executable the process was running after the exec call.\n\
6367 By default, the debugger will use the same inferior."),
6369 show_follow_exec_mode_string
,
6370 &setlist
, &showlist
);
6372 add_setshow_enum_cmd ("scheduler-locking", class_run
,
6373 scheduler_enums
, &scheduler_mode
, _("\
6374 Set mode for locking scheduler during execution."), _("\
6375 Show mode for locking scheduler during execution."), _("\
6376 off == no locking (threads may preempt at any time)\n\
6377 on == full locking (no thread except the current thread may run)\n\
6378 step == scheduler locked during every single-step operation.\n\
6379 In this mode, no other thread may run during a step command.\n\
6380 Other threads may run while stepping over a function call ('next')."),
6381 set_schedlock_func
, /* traps on target vector */
6382 show_scheduler_mode
,
6383 &setlist
, &showlist
);
6385 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
6386 Set mode for resuming threads of all processes."), _("\
6387 Show mode for resuming threads of all processes."), _("\
6388 When on, execution commands (such as 'continue' or 'next') resume all\n\
6389 threads of all processes. When off (which is the default), execution\n\
6390 commands only resume the threads of the current process. The set of\n\
6391 threads that are resumed is further refined by the scheduler-locking\n\
6392 mode (see help set scheduler-locking)."),
6394 show_schedule_multiple
,
6395 &setlist
, &showlist
);
6397 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
6398 Set mode of the step operation."), _("\
6399 Show mode of the step operation."), _("\
6400 When set, doing a step over a function without debug line information\n\
6401 will stop at the first instruction of that function. Otherwise, the\n\
6402 function is skipped and the step command stops at a different source line."),
6404 show_step_stop_if_no_debug
,
6405 &setlist
, &showlist
);
6407 add_setshow_enum_cmd ("displaced-stepping", class_run
,
6408 can_use_displaced_stepping_enum
,
6409 &can_use_displaced_stepping
, _("\
6410 Set debugger's willingness to use displaced stepping."), _("\
6411 Show debugger's willingness to use displaced stepping."), _("\
6412 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
6413 supported by the target architecture. If off, gdb will not use displaced\n\
6414 stepping to step over breakpoints, even if such is supported by the target\n\
6415 architecture. If auto (which is the default), gdb will use displaced stepping\n\
6416 if the target architecture supports it and non-stop mode is active, but will not\n\
6417 use it in all-stop mode (see help set non-stop)."),
6419 show_can_use_displaced_stepping
,
6420 &setlist
, &showlist
);
6422 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
6423 &exec_direction
, _("Set direction of execution.\n\
6424 Options are 'forward' or 'reverse'."),
6425 _("Show direction of execution (forward/reverse)."),
6426 _("Tells gdb whether to execute forward or backward."),
6427 set_exec_direction_func
, show_exec_direction_func
,
6428 &setlist
, &showlist
);
6430 /* Set/show detach-on-fork: user-settable mode. */
6432 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
6433 Set whether gdb will detach the child of a fork."), _("\
6434 Show whether gdb will detach the child of a fork."), _("\
6435 Tells gdb whether to detach the child of a fork."),
6436 NULL
, NULL
, &setlist
, &showlist
);
6438 /* ptid initializations */
6439 null_ptid
= ptid_build (0, 0, 0);
6440 minus_one_ptid
= ptid_build (-1, 0, 0);
6441 inferior_ptid
= null_ptid
;
6442 target_last_wait_ptid
= minus_one_ptid
;
6443 displaced_step_ptid
= null_ptid
;
6445 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
6446 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
6447 observer_attach_thread_exit (infrun_thread_thread_exit
);
6449 /* Explicitly create without lookup, since that tries to create a
6450 value with a void typed value, and when we get here, gdbarch
6451 isn't initialized yet. At this point, we're quite sure there
6452 isn't another convenience variable of the same name. */
6453 create_internalvar_type_lazy ("_siginfo", siginfo_make_value
);