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 int debug_displaced
= 0;
114 show_debug_displaced (struct ui_file
*file
, int from_tty
,
115 struct cmd_list_element
*c
, const char *value
)
117 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
120 static int debug_infrun
= 0;
122 show_debug_infrun (struct ui_file
*file
, int from_tty
,
123 struct cmd_list_element
*c
, const char *value
)
125 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
128 /* If the program uses ELF-style shared libraries, then calls to
129 functions in shared libraries go through stubs, which live in a
130 table called the PLT (Procedure Linkage Table). The first time the
131 function is called, the stub sends control to the dynamic linker,
132 which looks up the function's real address, patches the stub so
133 that future calls will go directly to the function, and then passes
134 control to the function.
136 If we are stepping at the source level, we don't want to see any of
137 this --- we just want to skip over the stub and the dynamic linker.
138 The simple approach is to single-step until control leaves the
141 However, on some systems (e.g., Red Hat's 5.2 distribution) the
142 dynamic linker calls functions in the shared C library, so you
143 can't tell from the PC alone whether the dynamic linker is still
144 running. In this case, we use a step-resume breakpoint to get us
145 past the dynamic linker, as if we were using "next" to step over a
148 in_solib_dynsym_resolve_code() says whether we're in the dynamic
149 linker code or not. Normally, this means we single-step. However,
150 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
151 address where we can place a step-resume breakpoint to get past the
152 linker's symbol resolution function.
154 in_solib_dynsym_resolve_code() can generally be implemented in a
155 pretty portable way, by comparing the PC against the address ranges
156 of the dynamic linker's sections.
158 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
159 it depends on internal details of the dynamic linker. It's usually
160 not too hard to figure out where to put a breakpoint, but it
161 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
162 sanity checking. If it can't figure things out, returning zero and
163 getting the (possibly confusing) stepping behavior is better than
164 signalling an error, which will obscure the change in the
167 /* This function returns TRUE if pc is the address of an instruction
168 that lies within the dynamic linker (such as the event hook, or the
171 This function must be used only when a dynamic linker event has
172 been caught, and the inferior is being stepped out of the hook, or
173 undefined results are guaranteed. */
175 #ifndef SOLIB_IN_DYNAMIC_LINKER
176 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
180 /* Convert the #defines into values. This is temporary until wfi control
181 flow is completely sorted out. */
183 #ifndef CANNOT_STEP_HW_WATCHPOINTS
184 #define CANNOT_STEP_HW_WATCHPOINTS 0
186 #undef CANNOT_STEP_HW_WATCHPOINTS
187 #define CANNOT_STEP_HW_WATCHPOINTS 1
190 /* Tables of how to react to signals; the user sets them. */
192 static unsigned char *signal_stop
;
193 static unsigned char *signal_print
;
194 static unsigned char *signal_program
;
196 #define SET_SIGS(nsigs,sigs,flags) \
198 int signum = (nsigs); \
199 while (signum-- > 0) \
200 if ((sigs)[signum]) \
201 (flags)[signum] = 1; \
204 #define UNSET_SIGS(nsigs,sigs,flags) \
206 int signum = (nsigs); \
207 while (signum-- > 0) \
208 if ((sigs)[signum]) \
209 (flags)[signum] = 0; \
212 /* Value to pass to target_resume() to cause all threads to resume */
214 #define RESUME_ALL minus_one_ptid
216 /* Command list pointer for the "stop" placeholder. */
218 static struct cmd_list_element
*stop_command
;
220 /* Function inferior was in as of last step command. */
222 static struct symbol
*step_start_function
;
224 /* Nonzero if we want to give control to the user when we're notified
225 of shared library events by the dynamic linker. */
226 static int stop_on_solib_events
;
228 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
229 struct cmd_list_element
*c
, const char *value
)
231 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
235 /* Nonzero means expecting a trace trap
236 and should stop the inferior and return silently when it happens. */
240 /* Save register contents here when executing a "finish" command or are
241 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
242 Thus this contains the return value from the called function (assuming
243 values are returned in a register). */
245 struct regcache
*stop_registers
;
247 /* Nonzero after stop if current stack frame should be printed. */
249 static int stop_print_frame
;
251 /* This is a cached copy of the pid/waitstatus of the last event
252 returned by target_wait()/deprecated_target_wait_hook(). This
253 information is returned by get_last_target_status(). */
254 static ptid_t target_last_wait_ptid
;
255 static struct target_waitstatus target_last_waitstatus
;
257 static void context_switch (ptid_t ptid
);
259 void init_thread_stepping_state (struct thread_info
*tss
);
261 void init_infwait_state (void);
263 static const char follow_fork_mode_child
[] = "child";
264 static const char follow_fork_mode_parent
[] = "parent";
266 static const char *follow_fork_mode_kind_names
[] = {
267 follow_fork_mode_child
,
268 follow_fork_mode_parent
,
272 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
274 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
275 struct cmd_list_element
*c
, const char *value
)
277 fprintf_filtered (file
, _("\
278 Debugger response to a program call of fork or vfork is \"%s\".\n"),
283 /* Tell the target to follow the fork we're stopped at. Returns true
284 if the inferior should be resumed; false, if the target for some
285 reason decided it's best not to resume. */
290 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
291 int should_resume
= 1;
292 struct thread_info
*tp
;
294 /* Copy user stepping state to the new inferior thread. FIXME: the
295 followed fork child thread should have a copy of most of the
296 parent thread structure's run control related fields, not just these.
297 Initialized to avoid "may be used uninitialized" warnings from gcc. */
298 struct breakpoint
*step_resume_breakpoint
= NULL
;
299 CORE_ADDR step_range_start
= 0;
300 CORE_ADDR step_range_end
= 0;
301 struct frame_id step_frame_id
= { 0 };
306 struct target_waitstatus wait_status
;
308 /* Get the last target status returned by target_wait(). */
309 get_last_target_status (&wait_ptid
, &wait_status
);
311 /* If not stopped at a fork event, then there's nothing else to
313 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
314 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
317 /* Check if we switched over from WAIT_PTID, since the event was
319 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
320 && !ptid_equal (inferior_ptid
, wait_ptid
))
322 /* We did. Switch back to WAIT_PTID thread, to tell the
323 target to follow it (in either direction). We'll
324 afterwards refuse to resume, and inform the user what
326 switch_to_thread (wait_ptid
);
331 tp
= inferior_thread ();
333 /* If there were any forks/vforks that were caught and are now to be
334 followed, then do so now. */
335 switch (tp
->pending_follow
.kind
)
337 case TARGET_WAITKIND_FORKED
:
338 case TARGET_WAITKIND_VFORKED
:
340 ptid_t parent
, child
;
342 /* If the user did a next/step, etc, over a fork call,
343 preserve the stepping state in the fork child. */
344 if (follow_child
&& should_resume
)
346 step_resume_breakpoint
347 = clone_momentary_breakpoint (tp
->step_resume_breakpoint
);
348 step_range_start
= tp
->step_range_start
;
349 step_range_end
= tp
->step_range_end
;
350 step_frame_id
= tp
->step_frame_id
;
352 /* For now, delete the parent's sr breakpoint, otherwise,
353 parent/child sr breakpoints are considered duplicates,
354 and the child version will not be installed. Remove
355 this when the breakpoints module becomes aware of
356 inferiors and address spaces. */
357 delete_step_resume_breakpoint (tp
);
358 tp
->step_range_start
= 0;
359 tp
->step_range_end
= 0;
360 tp
->step_frame_id
= null_frame_id
;
363 parent
= inferior_ptid
;
364 child
= tp
->pending_follow
.value
.related_pid
;
366 /* Tell the target to do whatever is necessary to follow
367 either parent or child. */
368 if (target_follow_fork (follow_child
))
370 /* Target refused to follow, or there's some other reason
371 we shouldn't resume. */
376 /* This pending follow fork event is now handled, one way
377 or another. The previous selected thread may be gone
378 from the lists by now, but if it is still around, need
379 to clear the pending follow request. */
380 tp
= find_thread_ptid (parent
);
382 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
384 /* This makes sure we don't try to apply the "Switched
385 over from WAIT_PID" logic above. */
386 nullify_last_target_wait_ptid ();
388 /* If we followed the child, switch to it... */
391 switch_to_thread (child
);
393 /* ... and preserve the stepping state, in case the
394 user was stepping over the fork call. */
397 tp
= inferior_thread ();
398 tp
->step_resume_breakpoint
= step_resume_breakpoint
;
399 tp
->step_range_start
= step_range_start
;
400 tp
->step_range_end
= step_range_end
;
401 tp
->step_frame_id
= step_frame_id
;
405 /* If we get here, it was because we're trying to
406 resume from a fork catchpoint, but, the user
407 has switched threads away from the thread that
408 forked. In that case, the resume command
409 issued is most likely not applicable to the
410 child, so just warn, and refuse to resume. */
412 Not resuming: switched threads before following fork child.\n"));
415 /* Reset breakpoints in the child as appropriate. */
416 follow_inferior_reset_breakpoints ();
419 switch_to_thread (parent
);
423 case TARGET_WAITKIND_SPURIOUS
:
424 /* Nothing to follow. */
427 internal_error (__FILE__
, __LINE__
,
428 "Unexpected pending_follow.kind %d\n",
429 tp
->pending_follow
.kind
);
433 return should_resume
;
437 follow_inferior_reset_breakpoints (void)
439 struct thread_info
*tp
= inferior_thread ();
441 /* Was there a step_resume breakpoint? (There was if the user
442 did a "next" at the fork() call.) If so, explicitly reset its
445 step_resumes are a form of bp that are made to be per-thread.
446 Since we created the step_resume bp when the parent process
447 was being debugged, and now are switching to the child process,
448 from the breakpoint package's viewpoint, that's a switch of
449 "threads". We must update the bp's notion of which thread
450 it is for, or it'll be ignored when it triggers. */
452 if (tp
->step_resume_breakpoint
)
453 breakpoint_re_set_thread (tp
->step_resume_breakpoint
);
455 /* Reinsert all breakpoints in the child. The user may have set
456 breakpoints after catching the fork, in which case those
457 were never set in the child, but only in the parent. This makes
458 sure the inserted breakpoints match the breakpoint list. */
460 breakpoint_re_set ();
461 insert_breakpoints ();
464 /* EXECD_PATHNAME is assumed to be non-NULL. */
467 follow_exec (ptid_t pid
, char *execd_pathname
)
469 struct target_ops
*tgt
;
470 struct thread_info
*th
= inferior_thread ();
472 /* This is an exec event that we actually wish to pay attention to.
473 Refresh our symbol table to the newly exec'd program, remove any
476 If there are breakpoints, they aren't really inserted now,
477 since the exec() transformed our inferior into a fresh set
480 We want to preserve symbolic breakpoints on the list, since
481 we have hopes that they can be reset after the new a.out's
482 symbol table is read.
484 However, any "raw" breakpoints must be removed from the list
485 (e.g., the solib bp's), since their address is probably invalid
488 And, we DON'T want to call delete_breakpoints() here, since
489 that may write the bp's "shadow contents" (the instruction
490 value that was overwritten witha TRAP instruction). Since
491 we now have a new a.out, those shadow contents aren't valid. */
492 update_breakpoints_after_exec ();
494 /* If there was one, it's gone now. We cannot truly step-to-next
495 statement through an exec(). */
496 th
->step_resume_breakpoint
= NULL
;
497 th
->step_range_start
= 0;
498 th
->step_range_end
= 0;
500 /* The target reports the exec event to the main thread, even if
501 some other thread does the exec, and even if the main thread was
502 already stopped --- if debugging in non-stop mode, it's possible
503 the user had the main thread held stopped in the previous image
504 --- release it now. This is the same behavior as step-over-exec
505 with scheduler-locking on in all-stop mode. */
506 th
->stop_requested
= 0;
508 /* What is this a.out's name? */
509 printf_unfiltered (_("Executing new program: %s\n"), execd_pathname
);
511 /* We've followed the inferior through an exec. Therefore, the
512 inferior has essentially been killed & reborn. */
514 gdb_flush (gdb_stdout
);
516 breakpoint_init_inferior (inf_execd
);
518 if (gdb_sysroot
&& *gdb_sysroot
)
520 char *name
= alloca (strlen (gdb_sysroot
)
521 + strlen (execd_pathname
)
523 strcpy (name
, gdb_sysroot
);
524 strcat (name
, execd_pathname
);
525 execd_pathname
= name
;
528 /* That a.out is now the one to use. */
529 exec_file_attach (execd_pathname
, 0);
531 /* Reset the shared library package. This ensures that we get a
532 shlib event when the child reaches "_start", at which point the
533 dld will have had a chance to initialize the child. */
534 /* Also, loading a symbol file below may trigger symbol lookups, and
535 we don't want those to be satisfied by the libraries of the
536 previous incarnation of this process. */
537 no_shared_libraries (NULL
, 0);
539 /* Load the main file's symbols. */
540 symbol_file_add_main (execd_pathname
, 0);
542 #ifdef SOLIB_CREATE_INFERIOR_HOOK
543 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
545 solib_create_inferior_hook ();
548 jit_inferior_created_hook ();
550 /* Reinsert all breakpoints. (Those which were symbolic have
551 been reset to the proper address in the new a.out, thanks
552 to symbol_file_command...) */
553 insert_breakpoints ();
555 /* The next resume of this inferior should bring it to the shlib
556 startup breakpoints. (If the user had also set bp's on
557 "main" from the old (parent) process, then they'll auto-
558 matically get reset there in the new process.) */
561 /* Non-zero if we just simulating a single-step. This is needed
562 because we cannot remove the breakpoints in the inferior process
563 until after the `wait' in `wait_for_inferior'. */
564 static int singlestep_breakpoints_inserted_p
= 0;
566 /* The thread we inserted single-step breakpoints for. */
567 static ptid_t singlestep_ptid
;
569 /* PC when we started this single-step. */
570 static CORE_ADDR singlestep_pc
;
572 /* If another thread hit the singlestep breakpoint, we save the original
573 thread here so that we can resume single-stepping it later. */
574 static ptid_t saved_singlestep_ptid
;
575 static int stepping_past_singlestep_breakpoint
;
577 /* If not equal to null_ptid, this means that after stepping over breakpoint
578 is finished, we need to switch to deferred_step_ptid, and step it.
580 The use case is when one thread has hit a breakpoint, and then the user
581 has switched to another thread and issued 'step'. We need to step over
582 breakpoint in the thread which hit the breakpoint, but then continue
583 stepping the thread user has selected. */
584 static ptid_t deferred_step_ptid
;
586 /* Displaced stepping. */
588 /* In non-stop debugging mode, we must take special care to manage
589 breakpoints properly; in particular, the traditional strategy for
590 stepping a thread past a breakpoint it has hit is unsuitable.
591 'Displaced stepping' is a tactic for stepping one thread past a
592 breakpoint it has hit while ensuring that other threads running
593 concurrently will hit the breakpoint as they should.
595 The traditional way to step a thread T off a breakpoint in a
596 multi-threaded program in all-stop mode is as follows:
598 a0) Initially, all threads are stopped, and breakpoints are not
600 a1) We single-step T, leaving breakpoints uninserted.
601 a2) We insert breakpoints, and resume all threads.
603 In non-stop debugging, however, this strategy is unsuitable: we
604 don't want to have to stop all threads in the system in order to
605 continue or step T past a breakpoint. Instead, we use displaced
608 n0) Initially, T is stopped, other threads are running, and
609 breakpoints are inserted.
610 n1) We copy the instruction "under" the breakpoint to a separate
611 location, outside the main code stream, making any adjustments
612 to the instruction, register, and memory state as directed by
614 n2) We single-step T over the instruction at its new location.
615 n3) We adjust the resulting register and memory state as directed
616 by T's architecture. This includes resetting T's PC to point
617 back into the main instruction stream.
620 This approach depends on the following gdbarch methods:
622 - gdbarch_max_insn_length and gdbarch_displaced_step_location
623 indicate where to copy the instruction, and how much space must
624 be reserved there. We use these in step n1.
626 - gdbarch_displaced_step_copy_insn copies a instruction to a new
627 address, and makes any necessary adjustments to the instruction,
628 register contents, and memory. We use this in step n1.
630 - gdbarch_displaced_step_fixup adjusts registers and memory after
631 we have successfuly single-stepped the instruction, to yield the
632 same effect the instruction would have had if we had executed it
633 at its original address. We use this in step n3.
635 - gdbarch_displaced_step_free_closure provides cleanup.
637 The gdbarch_displaced_step_copy_insn and
638 gdbarch_displaced_step_fixup functions must be written so that
639 copying an instruction with gdbarch_displaced_step_copy_insn,
640 single-stepping across the copied instruction, and then applying
641 gdbarch_displaced_insn_fixup should have the same effects on the
642 thread's memory and registers as stepping the instruction in place
643 would have. Exactly which responsibilities fall to the copy and
644 which fall to the fixup is up to the author of those functions.
646 See the comments in gdbarch.sh for details.
648 Note that displaced stepping and software single-step cannot
649 currently be used in combination, although with some care I think
650 they could be made to. Software single-step works by placing
651 breakpoints on all possible subsequent instructions; if the
652 displaced instruction is a PC-relative jump, those breakpoints
653 could fall in very strange places --- on pages that aren't
654 executable, or at addresses that are not proper instruction
655 boundaries. (We do generally let other threads run while we wait
656 to hit the software single-step breakpoint, and they might
657 encounter such a corrupted instruction.) One way to work around
658 this would be to have gdbarch_displaced_step_copy_insn fully
659 simulate the effect of PC-relative instructions (and return NULL)
660 on architectures that use software single-stepping.
662 In non-stop mode, we can have independent and simultaneous step
663 requests, so more than one thread may need to simultaneously step
664 over a breakpoint. The current implementation assumes there is
665 only one scratch space per process. In this case, we have to
666 serialize access to the scratch space. If thread A wants to step
667 over a breakpoint, but we are currently waiting for some other
668 thread to complete a displaced step, we leave thread A stopped and
669 place it in the displaced_step_request_queue. Whenever a displaced
670 step finishes, we pick the next thread in the queue and start a new
671 displaced step operation on it. See displaced_step_prepare and
672 displaced_step_fixup for details. */
674 /* If this is not null_ptid, this is the thread carrying out a
675 displaced single-step. This thread's state will require fixing up
676 once it has completed its step. */
677 static ptid_t displaced_step_ptid
;
679 struct displaced_step_request
682 struct displaced_step_request
*next
;
685 /* A queue of pending displaced stepping requests. */
686 struct displaced_step_request
*displaced_step_request_queue
;
688 /* The architecture the thread had when we stepped it. */
689 static struct gdbarch
*displaced_step_gdbarch
;
691 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
692 for post-step cleanup. */
693 static struct displaced_step_closure
*displaced_step_closure
;
695 /* The address of the original instruction, and the copy we made. */
696 static CORE_ADDR displaced_step_original
, displaced_step_copy
;
698 /* Saved contents of copy area. */
699 static gdb_byte
*displaced_step_saved_copy
;
701 /* Enum strings for "set|show displaced-stepping". */
703 static const char can_use_displaced_stepping_auto
[] = "auto";
704 static const char can_use_displaced_stepping_on
[] = "on";
705 static const char can_use_displaced_stepping_off
[] = "off";
706 static const char *can_use_displaced_stepping_enum
[] =
708 can_use_displaced_stepping_auto
,
709 can_use_displaced_stepping_on
,
710 can_use_displaced_stepping_off
,
714 /* If ON, and the architecture supports it, GDB will use displaced
715 stepping to step over breakpoints. If OFF, or if the architecture
716 doesn't support it, GDB will instead use the traditional
717 hold-and-step approach. If AUTO (which is the default), GDB will
718 decide which technique to use to step over breakpoints depending on
719 which of all-stop or non-stop mode is active --- displaced stepping
720 in non-stop mode; hold-and-step in all-stop mode. */
722 static const char *can_use_displaced_stepping
=
723 can_use_displaced_stepping_auto
;
726 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
727 struct cmd_list_element
*c
,
730 if (can_use_displaced_stepping
== can_use_displaced_stepping_auto
)
731 fprintf_filtered (file
, _("\
732 Debugger's willingness to use displaced stepping to step over \
733 breakpoints is %s (currently %s).\n"),
734 value
, non_stop
? "on" : "off");
736 fprintf_filtered (file
, _("\
737 Debugger's willingness to use displaced stepping to step over \
738 breakpoints is %s.\n"), value
);
741 /* Return non-zero if displaced stepping can/should be used to step
745 use_displaced_stepping (struct gdbarch
*gdbarch
)
747 return (((can_use_displaced_stepping
== can_use_displaced_stepping_auto
749 || can_use_displaced_stepping
== can_use_displaced_stepping_on
)
750 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
754 /* Clean out any stray displaced stepping state. */
756 displaced_step_clear (void)
758 /* Indicate that there is no cleanup pending. */
759 displaced_step_ptid
= null_ptid
;
761 if (displaced_step_closure
)
763 gdbarch_displaced_step_free_closure (displaced_step_gdbarch
,
764 displaced_step_closure
);
765 displaced_step_closure
= NULL
;
770 displaced_step_clear_cleanup (void *ignore
)
772 displaced_step_clear ();
775 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
777 displaced_step_dump_bytes (struct ui_file
*file
,
783 for (i
= 0; i
< len
; i
++)
784 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
785 fputs_unfiltered ("\n", file
);
788 /* Prepare to single-step, using displaced stepping.
790 Note that we cannot use displaced stepping when we have a signal to
791 deliver. If we have a signal to deliver and an instruction to step
792 over, then after the step, there will be no indication from the
793 target whether the thread entered a signal handler or ignored the
794 signal and stepped over the instruction successfully --- both cases
795 result in a simple SIGTRAP. In the first case we mustn't do a
796 fixup, and in the second case we must --- but we can't tell which.
797 Comments in the code for 'random signals' in handle_inferior_event
798 explain how we handle this case instead.
800 Returns 1 if preparing was successful -- this thread is going to be
801 stepped now; or 0 if displaced stepping this thread got queued. */
803 displaced_step_prepare (ptid_t ptid
)
805 struct cleanup
*old_cleanups
, *ignore_cleanups
;
806 struct regcache
*regcache
= get_thread_regcache (ptid
);
807 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
808 CORE_ADDR original
, copy
;
810 struct displaced_step_closure
*closure
;
812 /* We should never reach this function if the architecture does not
813 support displaced stepping. */
814 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
816 /* For the first cut, we're displaced stepping one thread at a
819 if (!ptid_equal (displaced_step_ptid
, null_ptid
))
821 /* Already waiting for a displaced step to finish. Defer this
822 request and place in queue. */
823 struct displaced_step_request
*req
, *new_req
;
826 fprintf_unfiltered (gdb_stdlog
,
827 "displaced: defering step of %s\n",
828 target_pid_to_str (ptid
));
830 new_req
= xmalloc (sizeof (*new_req
));
831 new_req
->ptid
= ptid
;
832 new_req
->next
= NULL
;
834 if (displaced_step_request_queue
)
836 for (req
= displaced_step_request_queue
;
843 displaced_step_request_queue
= new_req
;
850 fprintf_unfiltered (gdb_stdlog
,
851 "displaced: stepping %s now\n",
852 target_pid_to_str (ptid
));
855 displaced_step_clear ();
857 old_cleanups
= save_inferior_ptid ();
858 inferior_ptid
= ptid
;
860 original
= regcache_read_pc (regcache
);
862 copy
= gdbarch_displaced_step_location (gdbarch
);
863 len
= gdbarch_max_insn_length (gdbarch
);
865 /* Save the original contents of the copy area. */
866 displaced_step_saved_copy
= xmalloc (len
);
867 ignore_cleanups
= make_cleanup (free_current_contents
,
868 &displaced_step_saved_copy
);
869 read_memory (copy
, displaced_step_saved_copy
, len
);
872 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
873 paddress (gdbarch
, copy
));
874 displaced_step_dump_bytes (gdb_stdlog
, displaced_step_saved_copy
, len
);
877 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
878 original
, copy
, regcache
);
880 /* We don't support the fully-simulated case at present. */
881 gdb_assert (closure
);
883 /* Save the information we need to fix things up if the step
885 displaced_step_ptid
= ptid
;
886 displaced_step_gdbarch
= gdbarch
;
887 displaced_step_closure
= closure
;
888 displaced_step_original
= original
;
889 displaced_step_copy
= copy
;
891 make_cleanup (displaced_step_clear_cleanup
, 0);
893 /* Resume execution at the copy. */
894 regcache_write_pc (regcache
, copy
);
896 discard_cleanups (ignore_cleanups
);
898 do_cleanups (old_cleanups
);
901 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
902 paddress (gdbarch
, copy
));
908 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
, const gdb_byte
*myaddr
, int len
)
910 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
911 inferior_ptid
= ptid
;
912 write_memory (memaddr
, myaddr
, len
);
913 do_cleanups (ptid_cleanup
);
917 displaced_step_fixup (ptid_t event_ptid
, enum target_signal signal
)
919 struct cleanup
*old_cleanups
;
921 /* Was this event for the pid we displaced? */
922 if (ptid_equal (displaced_step_ptid
, null_ptid
)
923 || ! ptid_equal (displaced_step_ptid
, event_ptid
))
926 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, 0);
928 /* Restore the contents of the copy area. */
930 ULONGEST len
= gdbarch_max_insn_length (displaced_step_gdbarch
);
931 write_memory_ptid (displaced_step_ptid
, displaced_step_copy
,
932 displaced_step_saved_copy
, len
);
934 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s\n",
935 paddress (displaced_step_gdbarch
,
936 displaced_step_copy
));
939 /* Did the instruction complete successfully? */
940 if (signal
== TARGET_SIGNAL_TRAP
)
942 /* Fix up the resulting state. */
943 gdbarch_displaced_step_fixup (displaced_step_gdbarch
,
944 displaced_step_closure
,
945 displaced_step_original
,
947 get_thread_regcache (displaced_step_ptid
));
951 /* Since the instruction didn't complete, all we can do is
953 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
954 CORE_ADDR pc
= regcache_read_pc (regcache
);
955 pc
= displaced_step_original
+ (pc
- displaced_step_copy
);
956 regcache_write_pc (regcache
, pc
);
959 do_cleanups (old_cleanups
);
961 displaced_step_ptid
= null_ptid
;
963 /* Are there any pending displaced stepping requests? If so, run
965 while (displaced_step_request_queue
)
967 struct displaced_step_request
*head
;
969 struct regcache
*regcache
;
970 struct gdbarch
*gdbarch
;
973 head
= displaced_step_request_queue
;
975 displaced_step_request_queue
= head
->next
;
978 context_switch (ptid
);
980 regcache
= get_thread_regcache (ptid
);
981 actual_pc
= regcache_read_pc (regcache
);
983 if (breakpoint_here_p (actual_pc
))
986 fprintf_unfiltered (gdb_stdlog
,
987 "displaced: stepping queued %s now\n",
988 target_pid_to_str (ptid
));
990 displaced_step_prepare (ptid
);
992 gdbarch
= get_regcache_arch (regcache
);
996 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
999 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1000 paddress (gdbarch
, actual_pc
));
1001 read_memory (actual_pc
, buf
, sizeof (buf
));
1002 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1005 if (gdbarch_software_single_step_p (gdbarch
))
1006 target_resume (ptid
, 0, TARGET_SIGNAL_0
);
1008 target_resume (ptid
, 1, TARGET_SIGNAL_0
);
1010 /* Done, we're stepping a thread. */
1016 struct thread_info
*tp
= inferior_thread ();
1018 /* The breakpoint we were sitting under has since been
1020 tp
->trap_expected
= 0;
1022 /* Go back to what we were trying to do. */
1023 step
= currently_stepping (tp
);
1025 if (debug_displaced
)
1026 fprintf_unfiltered (gdb_stdlog
, "breakpoint is gone %s: step(%d)\n",
1027 target_pid_to_str (tp
->ptid
), step
);
1029 target_resume (ptid
, step
, TARGET_SIGNAL_0
);
1030 tp
->stop_signal
= TARGET_SIGNAL_0
;
1032 /* This request was discarded. See if there's any other
1033 thread waiting for its turn. */
1038 /* Update global variables holding ptids to hold NEW_PTID if they were
1039 holding OLD_PTID. */
1041 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1043 struct displaced_step_request
*it
;
1045 if (ptid_equal (inferior_ptid
, old_ptid
))
1046 inferior_ptid
= new_ptid
;
1048 if (ptid_equal (singlestep_ptid
, old_ptid
))
1049 singlestep_ptid
= new_ptid
;
1051 if (ptid_equal (displaced_step_ptid
, old_ptid
))
1052 displaced_step_ptid
= new_ptid
;
1054 if (ptid_equal (deferred_step_ptid
, old_ptid
))
1055 deferred_step_ptid
= new_ptid
;
1057 for (it
= displaced_step_request_queue
; it
; it
= it
->next
)
1058 if (ptid_equal (it
->ptid
, old_ptid
))
1059 it
->ptid
= new_ptid
;
1065 /* Things to clean up if we QUIT out of resume (). */
1067 resume_cleanups (void *ignore
)
1072 static const char schedlock_off
[] = "off";
1073 static const char schedlock_on
[] = "on";
1074 static const char schedlock_step
[] = "step";
1075 static const char *scheduler_enums
[] = {
1081 static const char *scheduler_mode
= schedlock_off
;
1083 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1084 struct cmd_list_element
*c
, const char *value
)
1086 fprintf_filtered (file
, _("\
1087 Mode for locking scheduler during execution is \"%s\".\n"),
1092 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1094 if (!target_can_lock_scheduler
)
1096 scheduler_mode
= schedlock_off
;
1097 error (_("Target '%s' cannot support this command."), target_shortname
);
1101 /* True if execution commands resume all threads of all processes by
1102 default; otherwise, resume only threads of the current inferior
1104 int sched_multi
= 0;
1106 /* Try to setup for software single stepping over the specified location.
1107 Return 1 if target_resume() should use hardware single step.
1109 GDBARCH the current gdbarch.
1110 PC the location to step over. */
1113 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1117 if (gdbarch_software_single_step_p (gdbarch
))
1119 if (use_displaced_stepping (gdbarch
))
1121 else if (gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1124 /* Do not pull these breakpoints until after a `wait' in
1125 `wait_for_inferior' */
1126 singlestep_breakpoints_inserted_p
= 1;
1127 singlestep_ptid
= inferior_ptid
;
1134 /* Resume the inferior, but allow a QUIT. This is useful if the user
1135 wants to interrupt some lengthy single-stepping operation
1136 (for child processes, the SIGINT goes to the inferior, and so
1137 we get a SIGINT random_signal, but for remote debugging and perhaps
1138 other targets, that's not true).
1140 STEP nonzero if we should step (zero to continue instead).
1141 SIG is the signal to give the inferior (zero for none). */
1143 resume (int step
, enum target_signal sig
)
1145 int should_resume
= 1;
1146 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
1147 struct regcache
*regcache
= get_current_regcache ();
1148 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1149 struct thread_info
*tp
= inferior_thread ();
1150 CORE_ADDR pc
= regcache_read_pc (regcache
);
1155 fprintf_unfiltered (gdb_stdlog
,
1156 "infrun: resume (step=%d, signal=%d), "
1157 "trap_expected=%d\n",
1158 step
, sig
, tp
->trap_expected
);
1160 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
1161 over an instruction that causes a page fault without triggering
1162 a hardware watchpoint. The kernel properly notices that it shouldn't
1163 stop, because the hardware watchpoint is not triggered, but it forgets
1164 the step request and continues the program normally.
1165 Work around the problem by removing hardware watchpoints if a step is
1166 requested, GDB will check for a hardware watchpoint trigger after the
1168 if (CANNOT_STEP_HW_WATCHPOINTS
&& step
)
1169 remove_hw_watchpoints ();
1172 /* Normally, by the time we reach `resume', the breakpoints are either
1173 removed or inserted, as appropriate. The exception is if we're sitting
1174 at a permanent breakpoint; we need to step over it, but permanent
1175 breakpoints can't be removed. So we have to test for it here. */
1176 if (breakpoint_here_p (pc
) == permanent_breakpoint_here
)
1178 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
1179 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
1182 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1183 how to step past a permanent breakpoint on this architecture. Try using\n\
1184 a command like `return' or `jump' to continue execution."));
1187 /* If enabled, step over breakpoints by executing a copy of the
1188 instruction at a different address.
1190 We can't use displaced stepping when we have a signal to deliver;
1191 the comments for displaced_step_prepare explain why. The
1192 comments in the handle_inferior event for dealing with 'random
1193 signals' explain what we do instead. */
1194 if (use_displaced_stepping (gdbarch
)
1195 && (tp
->trap_expected
1196 || (step
&& gdbarch_software_single_step_p (gdbarch
)))
1197 && sig
== TARGET_SIGNAL_0
)
1199 if (!displaced_step_prepare (inferior_ptid
))
1201 /* Got placed in displaced stepping queue. Will be resumed
1202 later when all the currently queued displaced stepping
1203 requests finish. The thread is not executing at this point,
1204 and the call to set_executing will be made later. But we
1205 need to call set_running here, since from frontend point of view,
1206 the thread is running. */
1207 set_running (inferior_ptid
, 1);
1208 discard_cleanups (old_cleanups
);
1213 /* Do we need to do it the hard way, w/temp breakpoints? */
1215 step
= maybe_software_singlestep (gdbarch
, pc
);
1221 /* If STEP is set, it's a request to use hardware stepping
1222 facilities. But in that case, we should never
1223 use singlestep breakpoint. */
1224 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1226 /* Decide the set of threads to ask the target to resume. Start
1227 by assuming everything will be resumed, than narrow the set
1228 by applying increasingly restricting conditions. */
1230 /* By default, resume all threads of all processes. */
1231 resume_ptid
= RESUME_ALL
;
1233 /* Maybe resume only all threads of the current process. */
1234 if (!sched_multi
&& target_supports_multi_process ())
1236 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1239 /* Maybe resume a single thread after all. */
1240 if (singlestep_breakpoints_inserted_p
1241 && stepping_past_singlestep_breakpoint
)
1243 /* The situation here is as follows. In thread T1 we wanted to
1244 single-step. Lacking hardware single-stepping we've
1245 set breakpoint at the PC of the next instruction -- call it
1246 P. After resuming, we've hit that breakpoint in thread T2.
1247 Now we've removed original breakpoint, inserted breakpoint
1248 at P+1, and try to step to advance T2 past breakpoint.
1249 We need to step only T2, as if T1 is allowed to freely run,
1250 it can run past P, and if other threads are allowed to run,
1251 they can hit breakpoint at P+1, and nested hits of single-step
1252 breakpoints is not something we'd want -- that's complicated
1253 to support, and has no value. */
1254 resume_ptid
= inferior_ptid
;
1256 else if ((step
|| singlestep_breakpoints_inserted_p
)
1257 && tp
->trap_expected
)
1259 /* We're allowing a thread to run past a breakpoint it has
1260 hit, by single-stepping the thread with the breakpoint
1261 removed. In which case, we need to single-step only this
1262 thread, and keep others stopped, as they can miss this
1263 breakpoint if allowed to run.
1265 The current code actually removes all breakpoints when
1266 doing this, not just the one being stepped over, so if we
1267 let other threads run, we can actually miss any
1268 breakpoint, not just the one at PC. */
1269 resume_ptid
= inferior_ptid
;
1273 /* With non-stop mode on, threads are always handled
1275 resume_ptid
= inferior_ptid
;
1277 else if ((scheduler_mode
== schedlock_on
)
1278 || (scheduler_mode
== schedlock_step
1279 && (step
|| singlestep_breakpoints_inserted_p
)))
1281 /* User-settable 'scheduler' mode requires solo thread resume. */
1282 resume_ptid
= inferior_ptid
;
1285 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1287 /* Most targets can step a breakpoint instruction, thus
1288 executing it normally. But if this one cannot, just
1289 continue and we will hit it anyway. */
1290 if (step
&& breakpoint_inserted_here_p (pc
))
1295 && use_displaced_stepping (gdbarch
)
1296 && tp
->trap_expected
)
1298 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1299 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
1300 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1303 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1304 paddress (resume_gdbarch
, actual_pc
));
1305 read_memory (actual_pc
, buf
, sizeof (buf
));
1306 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1309 /* Install inferior's terminal modes. */
1310 target_terminal_inferior ();
1312 /* Avoid confusing the next resume, if the next stop/resume
1313 happens to apply to another thread. */
1314 tp
->stop_signal
= TARGET_SIGNAL_0
;
1316 target_resume (resume_ptid
, step
, sig
);
1319 discard_cleanups (old_cleanups
);
1324 /* Clear out all variables saying what to do when inferior is continued.
1325 First do this, then set the ones you want, then call `proceed'. */
1328 clear_proceed_status_thread (struct thread_info
*tp
)
1331 fprintf_unfiltered (gdb_stdlog
,
1332 "infrun: clear_proceed_status_thread (%s)\n",
1333 target_pid_to_str (tp
->ptid
));
1335 tp
->trap_expected
= 0;
1336 tp
->step_range_start
= 0;
1337 tp
->step_range_end
= 0;
1338 tp
->step_frame_id
= null_frame_id
;
1339 tp
->step_stack_frame_id
= null_frame_id
;
1340 tp
->step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1341 tp
->stop_requested
= 0;
1345 tp
->proceed_to_finish
= 0;
1347 /* Discard any remaining commands or status from previous stop. */
1348 bpstat_clear (&tp
->stop_bpstat
);
1352 clear_proceed_status_callback (struct thread_info
*tp
, void *data
)
1354 if (is_exited (tp
->ptid
))
1357 clear_proceed_status_thread (tp
);
1362 clear_proceed_status (void)
1364 if (!ptid_equal (inferior_ptid
, null_ptid
))
1366 struct inferior
*inferior
;
1370 /* If in non-stop mode, only delete the per-thread status
1371 of the current thread. */
1372 clear_proceed_status_thread (inferior_thread ());
1376 /* In all-stop mode, delete the per-thread status of
1378 iterate_over_threads (clear_proceed_status_callback
, NULL
);
1381 inferior
= current_inferior ();
1382 inferior
->stop_soon
= NO_STOP_QUIETLY
;
1385 stop_after_trap
= 0;
1387 observer_notify_about_to_proceed ();
1391 regcache_xfree (stop_registers
);
1392 stop_registers
= NULL
;
1396 /* Check the current thread against the thread that reported the most recent
1397 event. If a step-over is required return TRUE and set the current thread
1398 to the old thread. Otherwise return FALSE.
1400 This should be suitable for any targets that support threads. */
1403 prepare_to_proceed (int step
)
1406 struct target_waitstatus wait_status
;
1407 int schedlock_enabled
;
1409 /* With non-stop mode on, threads are always handled individually. */
1410 gdb_assert (! non_stop
);
1412 /* Get the last target status returned by target_wait(). */
1413 get_last_target_status (&wait_ptid
, &wait_status
);
1415 /* Make sure we were stopped at a breakpoint. */
1416 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
1417 || wait_status
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1422 schedlock_enabled
= (scheduler_mode
== schedlock_on
1423 || (scheduler_mode
== schedlock_step
1426 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
1427 if (schedlock_enabled
)
1430 /* Don't switch over if we're about to resume some other process
1431 other than WAIT_PTID's, and schedule-multiple is off. */
1433 && ptid_get_pid (wait_ptid
) != ptid_get_pid (inferior_ptid
))
1436 /* Switched over from WAIT_PID. */
1437 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
1438 && !ptid_equal (inferior_ptid
, wait_ptid
))
1440 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
1442 if (breakpoint_here_p (regcache_read_pc (regcache
)))
1444 /* If stepping, remember current thread to switch back to. */
1446 deferred_step_ptid
= inferior_ptid
;
1448 /* Switch back to WAIT_PID thread. */
1449 switch_to_thread (wait_ptid
);
1451 /* We return 1 to indicate that there is a breakpoint here,
1452 so we need to step over it before continuing to avoid
1453 hitting it straight away. */
1461 /* Basic routine for continuing the program in various fashions.
1463 ADDR is the address to resume at, or -1 for resume where stopped.
1464 SIGGNAL is the signal to give it, or 0 for none,
1465 or -1 for act according to how it stopped.
1466 STEP is nonzero if should trap after one instruction.
1467 -1 means return after that and print nothing.
1468 You should probably set various step_... variables
1469 before calling here, if you are stepping.
1471 You should call clear_proceed_status before calling proceed. */
1474 proceed (CORE_ADDR addr
, enum target_signal siggnal
, int step
)
1476 struct regcache
*regcache
;
1477 struct gdbarch
*gdbarch
;
1478 struct thread_info
*tp
;
1482 /* If we're stopped at a fork/vfork, follow the branch set by the
1483 "set follow-fork-mode" command; otherwise, we'll just proceed
1484 resuming the current thread. */
1485 if (!follow_fork ())
1487 /* The target for some reason decided not to resume. */
1492 regcache
= get_current_regcache ();
1493 gdbarch
= get_regcache_arch (regcache
);
1494 pc
= regcache_read_pc (regcache
);
1497 step_start_function
= find_pc_function (pc
);
1499 stop_after_trap
= 1;
1501 if (addr
== (CORE_ADDR
) -1)
1503 if (pc
== stop_pc
&& breakpoint_here_p (pc
)
1504 && execution_direction
!= EXEC_REVERSE
)
1505 /* There is a breakpoint at the address we will resume at,
1506 step one instruction before inserting breakpoints so that
1507 we do not stop right away (and report a second hit at this
1510 Note, we don't do this in reverse, because we won't
1511 actually be executing the breakpoint insn anyway.
1512 We'll be (un-)executing the previous instruction. */
1515 else if (gdbarch_single_step_through_delay_p (gdbarch
)
1516 && gdbarch_single_step_through_delay (gdbarch
,
1517 get_current_frame ()))
1518 /* We stepped onto an instruction that needs to be stepped
1519 again before re-inserting the breakpoint, do so. */
1524 regcache_write_pc (regcache
, addr
);
1528 fprintf_unfiltered (gdb_stdlog
,
1529 "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
1530 paddress (gdbarch
, addr
), siggnal
, step
);
1533 /* In non-stop, each thread is handled individually. The context
1534 must already be set to the right thread here. */
1538 /* In a multi-threaded task we may select another thread and
1539 then continue or step.
1541 But if the old thread was stopped at a breakpoint, it will
1542 immediately cause another breakpoint stop without any
1543 execution (i.e. it will report a breakpoint hit incorrectly).
1544 So we must step over it first.
1546 prepare_to_proceed checks the current thread against the
1547 thread that reported the most recent event. If a step-over
1548 is required it returns TRUE and sets the current thread to
1550 if (prepare_to_proceed (step
))
1554 /* prepare_to_proceed may change the current thread. */
1555 tp
= inferior_thread ();
1559 tp
->trap_expected
= 1;
1560 /* If displaced stepping is enabled, we can step over the
1561 breakpoint without hitting it, so leave all breakpoints
1562 inserted. Otherwise we need to disable all breakpoints, step
1563 one instruction, and then re-add them when that step is
1565 if (!use_displaced_stepping (gdbarch
))
1566 remove_breakpoints ();
1569 /* We can insert breakpoints if we're not trying to step over one,
1570 or if we are stepping over one but we're using displaced stepping
1572 if (! tp
->trap_expected
|| use_displaced_stepping (gdbarch
))
1573 insert_breakpoints ();
1577 /* Pass the last stop signal to the thread we're resuming,
1578 irrespective of whether the current thread is the thread that
1579 got the last event or not. This was historically GDB's
1580 behaviour before keeping a stop_signal per thread. */
1582 struct thread_info
*last_thread
;
1584 struct target_waitstatus last_status
;
1586 get_last_target_status (&last_ptid
, &last_status
);
1587 if (!ptid_equal (inferior_ptid
, last_ptid
)
1588 && !ptid_equal (last_ptid
, null_ptid
)
1589 && !ptid_equal (last_ptid
, minus_one_ptid
))
1591 last_thread
= find_thread_ptid (last_ptid
);
1594 tp
->stop_signal
= last_thread
->stop_signal
;
1595 last_thread
->stop_signal
= TARGET_SIGNAL_0
;
1600 if (siggnal
!= TARGET_SIGNAL_DEFAULT
)
1601 tp
->stop_signal
= siggnal
;
1602 /* If this signal should not be seen by program,
1603 give it zero. Used for debugging signals. */
1604 else if (!signal_program
[tp
->stop_signal
])
1605 tp
->stop_signal
= TARGET_SIGNAL_0
;
1607 annotate_starting ();
1609 /* Make sure that output from GDB appears before output from the
1611 gdb_flush (gdb_stdout
);
1613 /* Refresh prev_pc value just prior to resuming. This used to be
1614 done in stop_stepping, however, setting prev_pc there did not handle
1615 scenarios such as inferior function calls or returning from
1616 a function via the return command. In those cases, the prev_pc
1617 value was not set properly for subsequent commands. The prev_pc value
1618 is used to initialize the starting line number in the ecs. With an
1619 invalid value, the gdb next command ends up stopping at the position
1620 represented by the next line table entry past our start position.
1621 On platforms that generate one line table entry per line, this
1622 is not a problem. However, on the ia64, the compiler generates
1623 extraneous line table entries that do not increase the line number.
1624 When we issue the gdb next command on the ia64 after an inferior call
1625 or a return command, we often end up a few instructions forward, still
1626 within the original line we started.
1628 An attempt was made to have init_execution_control_state () refresh
1629 the prev_pc value before calculating the line number. This approach
1630 did not work because on platforms that use ptrace, the pc register
1631 cannot be read unless the inferior is stopped. At that point, we
1632 are not guaranteed the inferior is stopped and so the regcache_read_pc ()
1633 call can fail. Setting the prev_pc value here ensures the value is
1634 updated correctly when the inferior is stopped. */
1635 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
1637 /* Fill in with reasonable starting values. */
1638 init_thread_stepping_state (tp
);
1640 /* Reset to normal state. */
1641 init_infwait_state ();
1643 /* Resume inferior. */
1644 resume (oneproc
|| step
|| bpstat_should_step (), tp
->stop_signal
);
1646 /* Wait for it to stop (if not standalone)
1647 and in any case decode why it stopped, and act accordingly. */
1648 /* Do this only if we are not using the event loop, or if the target
1649 does not support asynchronous execution. */
1650 if (!target_can_async_p ())
1652 wait_for_inferior (0);
1658 /* Start remote-debugging of a machine over a serial link. */
1661 start_remote (int from_tty
)
1663 struct inferior
*inferior
;
1664 init_wait_for_inferior ();
1666 inferior
= current_inferior ();
1667 inferior
->stop_soon
= STOP_QUIETLY_REMOTE
;
1669 /* Always go on waiting for the target, regardless of the mode. */
1670 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1671 indicate to wait_for_inferior that a target should timeout if
1672 nothing is returned (instead of just blocking). Because of this,
1673 targets expecting an immediate response need to, internally, set
1674 things up so that the target_wait() is forced to eventually
1676 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1677 differentiate to its caller what the state of the target is after
1678 the initial open has been performed. Here we're assuming that
1679 the target has stopped. It should be possible to eventually have
1680 target_open() return to the caller an indication that the target
1681 is currently running and GDB state should be set to the same as
1682 for an async run. */
1683 wait_for_inferior (0);
1685 /* Now that the inferior has stopped, do any bookkeeping like
1686 loading shared libraries. We want to do this before normal_stop,
1687 so that the displayed frame is up to date. */
1688 post_create_inferior (¤t_target
, from_tty
);
1693 /* Initialize static vars when a new inferior begins. */
1696 init_wait_for_inferior (void)
1698 /* These are meaningless until the first time through wait_for_inferior. */
1700 breakpoint_init_inferior (inf_starting
);
1702 clear_proceed_status ();
1704 stepping_past_singlestep_breakpoint
= 0;
1705 deferred_step_ptid
= null_ptid
;
1707 target_last_wait_ptid
= minus_one_ptid
;
1709 previous_inferior_ptid
= null_ptid
;
1710 init_infwait_state ();
1712 displaced_step_clear ();
1714 /* Discard any skipped inlined frames. */
1715 clear_inline_frame_state (minus_one_ptid
);
1719 /* This enum encodes possible reasons for doing a target_wait, so that
1720 wfi can call target_wait in one place. (Ultimately the call will be
1721 moved out of the infinite loop entirely.) */
1725 infwait_normal_state
,
1726 infwait_thread_hop_state
,
1727 infwait_step_watch_state
,
1728 infwait_nonstep_watch_state
1731 /* Why did the inferior stop? Used to print the appropriate messages
1732 to the interface from within handle_inferior_event(). */
1733 enum inferior_stop_reason
1735 /* Step, next, nexti, stepi finished. */
1737 /* Inferior terminated by signal. */
1739 /* Inferior exited. */
1741 /* Inferior received signal, and user asked to be notified. */
1743 /* Reverse execution -- target ran out of history info. */
1747 /* The PTID we'll do a target_wait on.*/
1750 /* Current inferior wait state. */
1751 enum infwait_states infwait_state
;
1753 /* Data to be passed around while handling an event. This data is
1754 discarded between events. */
1755 struct execution_control_state
1758 /* The thread that got the event, if this was a thread event; NULL
1760 struct thread_info
*event_thread
;
1762 struct target_waitstatus ws
;
1764 CORE_ADDR stop_func_start
;
1765 CORE_ADDR stop_func_end
;
1766 char *stop_func_name
;
1767 int new_thread_event
;
1771 static void init_execution_control_state (struct execution_control_state
*ecs
);
1773 static void handle_inferior_event (struct execution_control_state
*ecs
);
1775 static void handle_step_into_function (struct gdbarch
*gdbarch
,
1776 struct execution_control_state
*ecs
);
1777 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
1778 struct execution_control_state
*ecs
);
1779 static void insert_step_resume_breakpoint_at_frame (struct frame_info
*step_frame
);
1780 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
1781 static void insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
1782 struct symtab_and_line sr_sal
,
1783 struct frame_id sr_id
);
1784 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
1786 static void stop_stepping (struct execution_control_state
*ecs
);
1787 static void prepare_to_wait (struct execution_control_state
*ecs
);
1788 static void keep_going (struct execution_control_state
*ecs
);
1789 static void print_stop_reason (enum inferior_stop_reason stop_reason
,
1792 /* Callback for iterate over threads. If the thread is stopped, but
1793 the user/frontend doesn't know about that yet, go through
1794 normal_stop, as if the thread had just stopped now. ARG points at
1795 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
1796 ptid_is_pid(PTID) is true, applies to all threads of the process
1797 pointed at by PTID. Otherwise, apply only to the thread pointed by
1801 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
1803 ptid_t ptid
= * (ptid_t
*) arg
;
1805 if ((ptid_equal (info
->ptid
, ptid
)
1806 || ptid_equal (minus_one_ptid
, ptid
)
1807 || (ptid_is_pid (ptid
)
1808 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
1809 && is_running (info
->ptid
)
1810 && !is_executing (info
->ptid
))
1812 struct cleanup
*old_chain
;
1813 struct execution_control_state ecss
;
1814 struct execution_control_state
*ecs
= &ecss
;
1816 memset (ecs
, 0, sizeof (*ecs
));
1818 old_chain
= make_cleanup_restore_current_thread ();
1820 switch_to_thread (info
->ptid
);
1822 /* Go through handle_inferior_event/normal_stop, so we always
1823 have consistent output as if the stop event had been
1825 ecs
->ptid
= info
->ptid
;
1826 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
1827 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
1828 ecs
->ws
.value
.sig
= TARGET_SIGNAL_0
;
1830 handle_inferior_event (ecs
);
1832 if (!ecs
->wait_some_more
)
1834 struct thread_info
*tp
;
1838 /* Finish off the continuations. The continations
1839 themselves are responsible for realising the thread
1840 didn't finish what it was supposed to do. */
1841 tp
= inferior_thread ();
1842 do_all_intermediate_continuations_thread (tp
);
1843 do_all_continuations_thread (tp
);
1846 do_cleanups (old_chain
);
1852 /* This function is attached as a "thread_stop_requested" observer.
1853 Cleanup local state that assumed the PTID was to be resumed, and
1854 report the stop to the frontend. */
1857 infrun_thread_stop_requested (ptid_t ptid
)
1859 struct displaced_step_request
*it
, *next
, *prev
= NULL
;
1861 /* PTID was requested to stop. Remove it from the displaced
1862 stepping queue, so we don't try to resume it automatically. */
1863 for (it
= displaced_step_request_queue
; it
; it
= next
)
1867 if (ptid_equal (it
->ptid
, ptid
)
1868 || ptid_equal (minus_one_ptid
, ptid
)
1869 || (ptid_is_pid (ptid
)
1870 && ptid_get_pid (ptid
) == ptid_get_pid (it
->ptid
)))
1872 if (displaced_step_request_queue
== it
)
1873 displaced_step_request_queue
= it
->next
;
1875 prev
->next
= it
->next
;
1883 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
1887 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
1889 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
1890 nullify_last_target_wait_ptid ();
1893 /* Callback for iterate_over_threads. */
1896 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
1898 if (is_exited (info
->ptid
))
1901 delete_step_resume_breakpoint (info
);
1905 /* In all-stop, delete the step resume breakpoint of any thread that
1906 had one. In non-stop, delete the step resume breakpoint of the
1907 thread that just stopped. */
1910 delete_step_thread_step_resume_breakpoint (void)
1912 if (!target_has_execution
1913 || ptid_equal (inferior_ptid
, null_ptid
))
1914 /* If the inferior has exited, we have already deleted the step
1915 resume breakpoints out of GDB's lists. */
1920 /* If in non-stop mode, only delete the step-resume or
1921 longjmp-resume breakpoint of the thread that just stopped
1923 struct thread_info
*tp
= inferior_thread ();
1924 delete_step_resume_breakpoint (tp
);
1927 /* In all-stop mode, delete all step-resume and longjmp-resume
1928 breakpoints of any thread that had them. */
1929 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
1932 /* A cleanup wrapper. */
1935 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
1937 delete_step_thread_step_resume_breakpoint ();
1940 /* Pretty print the results of target_wait, for debugging purposes. */
1943 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
1944 const struct target_waitstatus
*ws
)
1946 char *status_string
= target_waitstatus_to_string (ws
);
1947 struct ui_file
*tmp_stream
= mem_fileopen ();
1950 /* The text is split over several lines because it was getting too long.
1951 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
1952 output as a unit; we want only one timestamp printed if debug_timestamp
1955 fprintf_unfiltered (tmp_stream
,
1956 "infrun: target_wait (%d", PIDGET (waiton_ptid
));
1957 if (PIDGET (waiton_ptid
) != -1)
1958 fprintf_unfiltered (tmp_stream
,
1959 " [%s]", target_pid_to_str (waiton_ptid
));
1960 fprintf_unfiltered (tmp_stream
, ", status) =\n");
1961 fprintf_unfiltered (tmp_stream
,
1962 "infrun: %d [%s],\n",
1963 PIDGET (result_ptid
), target_pid_to_str (result_ptid
));
1964 fprintf_unfiltered (tmp_stream
,
1968 text
= ui_file_xstrdup (tmp_stream
, NULL
);
1970 /* This uses %s in part to handle %'s in the text, but also to avoid
1971 a gcc error: the format attribute requires a string literal. */
1972 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
1974 xfree (status_string
);
1976 ui_file_delete (tmp_stream
);
1979 /* Wait for control to return from inferior to debugger.
1981 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
1982 as if they were SIGTRAP signals. This can be useful during
1983 the startup sequence on some targets such as HP/UX, where
1984 we receive an EXEC event instead of the expected SIGTRAP.
1986 If inferior gets a signal, we may decide to start it up again
1987 instead of returning. That is why there is a loop in this function.
1988 When this function actually returns it means the inferior
1989 should be left stopped and GDB should read more commands. */
1992 wait_for_inferior (int treat_exec_as_sigtrap
)
1994 struct cleanup
*old_cleanups
;
1995 struct execution_control_state ecss
;
1996 struct execution_control_state
*ecs
;
2000 (gdb_stdlog
, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
2001 treat_exec_as_sigtrap
);
2004 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
2007 memset (ecs
, 0, sizeof (*ecs
));
2009 /* We'll update this if & when we switch to a new thread. */
2010 previous_inferior_ptid
= inferior_ptid
;
2014 struct cleanup
*old_chain
;
2016 /* We have to invalidate the registers BEFORE calling target_wait
2017 because they can be loaded from the target while in target_wait.
2018 This makes remote debugging a bit more efficient for those
2019 targets that provide critical registers as part of their normal
2020 status mechanism. */
2022 overlay_cache_invalid
= 1;
2023 registers_changed ();
2025 if (deprecated_target_wait_hook
)
2026 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2028 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2031 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2033 if (treat_exec_as_sigtrap
&& ecs
->ws
.kind
== TARGET_WAITKIND_EXECD
)
2035 xfree (ecs
->ws
.value
.execd_pathname
);
2036 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2037 ecs
->ws
.value
.sig
= TARGET_SIGNAL_TRAP
;
2040 /* If an error happens while handling the event, propagate GDB's
2041 knowledge of the executing state to the frontend/user running
2043 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2045 if (ecs
->ws
.kind
== TARGET_WAITKIND_SYSCALL_ENTRY
2046 || ecs
->ws
.kind
== TARGET_WAITKIND_SYSCALL_RETURN
)
2047 ecs
->ws
.value
.syscall_number
= UNKNOWN_SYSCALL
;
2049 /* Now figure out what to do with the result of the result. */
2050 handle_inferior_event (ecs
);
2052 /* No error, don't finish the state yet. */
2053 discard_cleanups (old_chain
);
2055 if (!ecs
->wait_some_more
)
2059 do_cleanups (old_cleanups
);
2062 /* Asynchronous version of wait_for_inferior. It is called by the
2063 event loop whenever a change of state is detected on the file
2064 descriptor corresponding to the target. It can be called more than
2065 once to complete a single execution command. In such cases we need
2066 to keep the state in a global variable ECSS. If it is the last time
2067 that this function is called for a single execution command, then
2068 report to the user that the inferior has stopped, and do the
2069 necessary cleanups. */
2072 fetch_inferior_event (void *client_data
)
2074 struct execution_control_state ecss
;
2075 struct execution_control_state
*ecs
= &ecss
;
2076 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2077 struct cleanup
*ts_old_chain
;
2078 int was_sync
= sync_execution
;
2080 memset (ecs
, 0, sizeof (*ecs
));
2082 /* We'll update this if & when we switch to a new thread. */
2083 previous_inferior_ptid
= inferior_ptid
;
2086 /* In non-stop mode, the user/frontend should not notice a thread
2087 switch due to internal events. Make sure we reverse to the
2088 user selected thread and frame after handling the event and
2089 running any breakpoint commands. */
2090 make_cleanup_restore_current_thread ();
2092 /* We have to invalidate the registers BEFORE calling target_wait
2093 because they can be loaded from the target while in target_wait.
2094 This makes remote debugging a bit more efficient for those
2095 targets that provide critical registers as part of their normal
2096 status mechanism. */
2098 overlay_cache_invalid
= 1;
2099 registers_changed ();
2101 if (deprecated_target_wait_hook
)
2103 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2105 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2108 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2111 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
2112 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2113 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2114 /* In non-stop mode, each thread is handled individually. Switch
2115 early, so the global state is set correctly for this
2117 context_switch (ecs
->ptid
);
2119 /* If an error happens while handling the event, propagate GDB's
2120 knowledge of the executing state to the frontend/user running
2123 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2125 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2127 /* Now figure out what to do with the result of the result. */
2128 handle_inferior_event (ecs
);
2130 if (!ecs
->wait_some_more
)
2132 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2134 delete_step_thread_step_resume_breakpoint ();
2136 /* We may not find an inferior if this was a process exit. */
2137 if (inf
== NULL
|| inf
->stop_soon
== NO_STOP_QUIETLY
)
2140 if (target_has_execution
2141 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2142 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2143 && ecs
->event_thread
->step_multi
2144 && ecs
->event_thread
->stop_step
)
2145 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2147 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2150 /* No error, don't finish the thread states yet. */
2151 discard_cleanups (ts_old_chain
);
2153 /* Revert thread and frame. */
2154 do_cleanups (old_chain
);
2156 /* If the inferior was in sync execution mode, and now isn't,
2157 restore the prompt. */
2158 if (was_sync
&& !sync_execution
)
2159 display_gdb_prompt (0);
2162 /* Record the frame and location we're currently stepping through. */
2164 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2166 struct thread_info
*tp
= inferior_thread ();
2168 tp
->step_frame_id
= get_frame_id (frame
);
2169 tp
->step_stack_frame_id
= get_stack_frame_id (frame
);
2171 tp
->current_symtab
= sal
.symtab
;
2172 tp
->current_line
= sal
.line
;
2175 /* Prepare an execution control state for looping through a
2176 wait_for_inferior-type loop. */
2179 init_execution_control_state (struct execution_control_state
*ecs
)
2181 ecs
->random_signal
= 0;
2184 /* Clear context switchable stepping state. */
2187 init_thread_stepping_state (struct thread_info
*tss
)
2189 tss
->stepping_over_breakpoint
= 0;
2190 tss
->step_after_step_resume_breakpoint
= 0;
2191 tss
->stepping_through_solib_after_catch
= 0;
2192 tss
->stepping_through_solib_catchpoints
= NULL
;
2195 /* Return the cached copy of the last pid/waitstatus returned by
2196 target_wait()/deprecated_target_wait_hook(). The data is actually
2197 cached by handle_inferior_event(), which gets called immediately
2198 after target_wait()/deprecated_target_wait_hook(). */
2201 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2203 *ptidp
= target_last_wait_ptid
;
2204 *status
= target_last_waitstatus
;
2208 nullify_last_target_wait_ptid (void)
2210 target_last_wait_ptid
= minus_one_ptid
;
2213 /* Switch thread contexts. */
2216 context_switch (ptid_t ptid
)
2220 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2221 target_pid_to_str (inferior_ptid
));
2222 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2223 target_pid_to_str (ptid
));
2226 switch_to_thread (ptid
);
2230 adjust_pc_after_break (struct execution_control_state
*ecs
)
2232 struct regcache
*regcache
;
2233 struct gdbarch
*gdbarch
;
2234 CORE_ADDR breakpoint_pc
;
2236 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2237 we aren't, just return.
2239 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2240 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2241 implemented by software breakpoints should be handled through the normal
2244 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2245 different signals (SIGILL or SIGEMT for instance), but it is less
2246 clear where the PC is pointing afterwards. It may not match
2247 gdbarch_decr_pc_after_break. I don't know any specific target that
2248 generates these signals at breakpoints (the code has been in GDB since at
2249 least 1992) so I can not guess how to handle them here.
2251 In earlier versions of GDB, a target with
2252 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2253 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2254 target with both of these set in GDB history, and it seems unlikely to be
2255 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2257 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2260 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
2263 /* In reverse execution, when a breakpoint is hit, the instruction
2264 under it has already been de-executed. The reported PC always
2265 points at the breakpoint address, so adjusting it further would
2266 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2269 B1 0x08000000 : INSN1
2270 B2 0x08000001 : INSN2
2272 PC -> 0x08000003 : INSN4
2274 Say you're stopped at 0x08000003 as above. Reverse continuing
2275 from that point should hit B2 as below. Reading the PC when the
2276 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2277 been de-executed already.
2279 B1 0x08000000 : INSN1
2280 B2 PC -> 0x08000001 : INSN2
2284 We can't apply the same logic as for forward execution, because
2285 we would wrongly adjust the PC to 0x08000000, since there's a
2286 breakpoint at PC - 1. We'd then report a hit on B1, although
2287 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2289 if (execution_direction
== EXEC_REVERSE
)
2292 /* If this target does not decrement the PC after breakpoints, then
2293 we have nothing to do. */
2294 regcache
= get_thread_regcache (ecs
->ptid
);
2295 gdbarch
= get_regcache_arch (regcache
);
2296 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
2299 /* Find the location where (if we've hit a breakpoint) the
2300 breakpoint would be. */
2301 breakpoint_pc
= regcache_read_pc (regcache
)
2302 - gdbarch_decr_pc_after_break (gdbarch
);
2304 /* Check whether there actually is a software breakpoint inserted at
2307 If in non-stop mode, a race condition is possible where we've
2308 removed a breakpoint, but stop events for that breakpoint were
2309 already queued and arrive later. To suppress those spurious
2310 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
2311 and retire them after a number of stop events are reported. */
2312 if (software_breakpoint_inserted_here_p (breakpoint_pc
)
2313 || (non_stop
&& moribund_breakpoint_here_p (breakpoint_pc
)))
2315 struct cleanup
*old_cleanups
= NULL
;
2317 old_cleanups
= record_gdb_operation_disable_set ();
2319 /* When using hardware single-step, a SIGTRAP is reported for both
2320 a completed single-step and a software breakpoint. Need to
2321 differentiate between the two, as the latter needs adjusting
2322 but the former does not.
2324 The SIGTRAP can be due to a completed hardware single-step only if
2325 - we didn't insert software single-step breakpoints
2326 - the thread to be examined is still the current thread
2327 - this thread is currently being stepped
2329 If any of these events did not occur, we must have stopped due
2330 to hitting a software breakpoint, and have to back up to the
2333 As a special case, we could have hardware single-stepped a
2334 software breakpoint. In this case (prev_pc == breakpoint_pc),
2335 we also need to back up to the breakpoint address. */
2337 if (singlestep_breakpoints_inserted_p
2338 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
2339 || !currently_stepping (ecs
->event_thread
)
2340 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
2341 regcache_write_pc (regcache
, breakpoint_pc
);
2344 do_cleanups (old_cleanups
);
2349 init_infwait_state (void)
2351 waiton_ptid
= pid_to_ptid (-1);
2352 infwait_state
= infwait_normal_state
;
2356 error_is_running (void)
2359 Cannot execute this command while the selected thread is running."));
2363 ensure_not_running (void)
2365 if (is_running (inferior_ptid
))
2366 error_is_running ();
2370 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
2372 for (frame
= get_prev_frame (frame
);
2374 frame
= get_prev_frame (frame
))
2376 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
2378 if (get_frame_type (frame
) != INLINE_FRAME
)
2385 /* Auxiliary function that handles syscall entry/return events.
2386 It returns 1 if the inferior should keep going (and GDB
2387 should ignore the event), or 0 if the event deserves to be
2390 deal_with_syscall_event (struct execution_control_state
*ecs
)
2392 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
2393 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2394 int syscall_number
= gdbarch_get_syscall_number (gdbarch
,
2396 target_last_waitstatus
.value
.syscall_number
= syscall_number
;
2398 if (catch_syscall_enabled () > 0
2399 && catching_syscall_number (syscall_number
) > 0)
2402 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
2404 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2406 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2408 context_switch (ecs
->ptid
);
2409 reinit_frame_cache ();
2412 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2414 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2416 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2418 /* If no catchpoint triggered for this, then keep going. */
2419 if (ecs
->random_signal
)
2421 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2429 resume (0, TARGET_SIGNAL_0
);
2430 prepare_to_wait (ecs
);
2435 /* Given an execution control state that has been freshly filled in
2436 by an event from the inferior, figure out what it means and take
2437 appropriate action. */
2440 handle_inferior_event (struct execution_control_state
*ecs
)
2442 struct frame_info
*frame
;
2443 struct gdbarch
*gdbarch
;
2444 int sw_single_step_trap_p
= 0;
2445 int stopped_by_watchpoint
;
2446 int stepped_after_stopped_by_watchpoint
= 0;
2447 struct symtab_and_line stop_pc_sal
;
2448 enum stop_kind stop_soon
;
2450 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2451 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2452 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
2454 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2456 stop_soon
= inf
->stop_soon
;
2459 stop_soon
= NO_STOP_QUIETLY
;
2461 /* Cache the last pid/waitstatus. */
2462 target_last_wait_ptid
= ecs
->ptid
;
2463 target_last_waitstatus
= ecs
->ws
;
2465 /* Always clear state belonging to the previous time we stopped. */
2466 stop_stack_dummy
= 0;
2468 /* If it's a new process, add it to the thread database */
2470 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
2471 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
2472 && !in_thread_list (ecs
->ptid
));
2474 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2475 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
2476 add_thread (ecs
->ptid
);
2478 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
2480 /* Dependent on valid ECS->EVENT_THREAD. */
2481 adjust_pc_after_break (ecs
);
2483 /* Dependent on the current PC value modified by adjust_pc_after_break. */
2484 reinit_frame_cache ();
2486 if (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
2488 breakpoint_retire_moribund ();
2490 /* Mark the non-executing threads accordingly. In all-stop, all
2491 threads of all processes are stopped when we get any event
2492 reported. In non-stop mode, only the event thread stops. If
2493 we're handling a process exit in non-stop mode, there's
2494 nothing to do, as threads of the dead process are gone, and
2495 threads of any other process were left running. */
2497 set_executing (minus_one_ptid
, 0);
2498 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2499 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
2500 set_executing (inferior_ptid
, 0);
2503 switch (infwait_state
)
2505 case infwait_thread_hop_state
:
2507 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
2510 case infwait_normal_state
:
2512 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
2515 case infwait_step_watch_state
:
2517 fprintf_unfiltered (gdb_stdlog
,
2518 "infrun: infwait_step_watch_state\n");
2520 stepped_after_stopped_by_watchpoint
= 1;
2523 case infwait_nonstep_watch_state
:
2525 fprintf_unfiltered (gdb_stdlog
,
2526 "infrun: infwait_nonstep_watch_state\n");
2527 insert_breakpoints ();
2529 /* FIXME-maybe: is this cleaner than setting a flag? Does it
2530 handle things like signals arriving and other things happening
2531 in combination correctly? */
2532 stepped_after_stopped_by_watchpoint
= 1;
2536 internal_error (__FILE__
, __LINE__
, _("bad switch"));
2539 infwait_state
= infwait_normal_state
;
2540 waiton_ptid
= pid_to_ptid (-1);
2542 switch (ecs
->ws
.kind
)
2544 case TARGET_WAITKIND_LOADED
:
2546 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
2547 /* Ignore gracefully during startup of the inferior, as it might
2548 be the shell which has just loaded some objects, otherwise
2549 add the symbols for the newly loaded objects. Also ignore at
2550 the beginning of an attach or remote session; we will query
2551 the full list of libraries once the connection is
2553 if (stop_soon
== NO_STOP_QUIETLY
)
2555 /* Check for any newly added shared libraries if we're
2556 supposed to be adding them automatically. Switch
2557 terminal for any messages produced by
2558 breakpoint_re_set. */
2559 target_terminal_ours_for_output ();
2560 /* NOTE: cagney/2003-11-25: Make certain that the target
2561 stack's section table is kept up-to-date. Architectures,
2562 (e.g., PPC64), use the section table to perform
2563 operations such as address => section name and hence
2564 require the table to contain all sections (including
2565 those found in shared libraries). */
2567 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2569 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2571 target_terminal_inferior ();
2573 /* If requested, stop when the dynamic linker notifies
2574 gdb of events. This allows the user to get control
2575 and place breakpoints in initializer routines for
2576 dynamically loaded objects (among other things). */
2577 if (stop_on_solib_events
)
2579 stop_stepping (ecs
);
2583 /* NOTE drow/2007-05-11: This might be a good place to check
2584 for "catch load". */
2587 /* If we are skipping through a shell, or through shared library
2588 loading that we aren't interested in, resume the program. If
2589 we're running the program normally, also resume. But stop if
2590 we're attaching or setting up a remote connection. */
2591 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
2593 /* Loading of shared libraries might have changed breakpoint
2594 addresses. Make sure new breakpoints are inserted. */
2595 if (stop_soon
== NO_STOP_QUIETLY
2596 && !breakpoints_always_inserted_mode ())
2597 insert_breakpoints ();
2598 resume (0, TARGET_SIGNAL_0
);
2599 prepare_to_wait (ecs
);
2605 case TARGET_WAITKIND_SPURIOUS
:
2607 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
2608 resume (0, TARGET_SIGNAL_0
);
2609 prepare_to_wait (ecs
);
2612 case TARGET_WAITKIND_EXITED
:
2614 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
2615 inferior_ptid
= ecs
->ptid
;
2616 target_terminal_ours (); /* Must do this before mourn anyway */
2617 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
2619 /* Record the exit code in the convenience variable $_exitcode, so
2620 that the user can inspect this again later. */
2621 set_internalvar_integer (lookup_internalvar ("_exitcode"),
2622 (LONGEST
) ecs
->ws
.value
.integer
);
2623 gdb_flush (gdb_stdout
);
2624 target_mourn_inferior ();
2625 singlestep_breakpoints_inserted_p
= 0;
2626 stop_print_frame
= 0;
2627 stop_stepping (ecs
);
2630 case TARGET_WAITKIND_SIGNALLED
:
2632 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2633 inferior_ptid
= ecs
->ptid
;
2634 stop_print_frame
= 0;
2635 target_terminal_ours (); /* Must do this before mourn anyway */
2637 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2638 reach here unless the inferior is dead. However, for years
2639 target_kill() was called here, which hints that fatal signals aren't
2640 really fatal on some systems. If that's true, then some changes
2642 target_mourn_inferior ();
2644 print_stop_reason (SIGNAL_EXITED
, ecs
->ws
.value
.sig
);
2645 singlestep_breakpoints_inserted_p
= 0;
2646 stop_stepping (ecs
);
2649 /* The following are the only cases in which we keep going;
2650 the above cases end in a continue or goto. */
2651 case TARGET_WAITKIND_FORKED
:
2652 case TARGET_WAITKIND_VFORKED
:
2654 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2656 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2658 context_switch (ecs
->ptid
);
2659 reinit_frame_cache ();
2662 /* Immediately detach breakpoints from the child before there's
2663 any chance of letting the user delete breakpoints from the
2664 breakpoint lists. If we don't do this early, it's easy to
2665 leave left over traps in the child, vis: "break foo; catch
2666 fork; c; <fork>; del; c; <child calls foo>". We only follow
2667 the fork on the last `continue', and by that time the
2668 breakpoint at "foo" is long gone from the breakpoint table.
2669 If we vforked, then we don't need to unpatch here, since both
2670 parent and child are sharing the same memory pages; we'll
2671 need to unpatch at follow/detach time instead to be certain
2672 that new breakpoints added between catchpoint hit time and
2673 vfork follow are detached. */
2674 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
2676 int child_pid
= ptid_get_pid (ecs
->ws
.value
.related_pid
);
2678 /* This won't actually modify the breakpoint list, but will
2679 physically remove the breakpoints from the child. */
2680 detach_breakpoints (child_pid
);
2683 /* In case the event is caught by a catchpoint, remember that
2684 the event is to be followed at the next resume of the thread,
2685 and not immediately. */
2686 ecs
->event_thread
->pending_follow
= ecs
->ws
;
2688 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2690 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2692 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2694 /* If no catchpoint triggered for this, then keep going. */
2695 if (ecs
->random_signal
)
2699 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2701 should_resume
= follow_fork ();
2703 ecs
->event_thread
= inferior_thread ();
2704 ecs
->ptid
= inferior_ptid
;
2709 stop_stepping (ecs
);
2712 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2713 goto process_event_stop_test
;
2715 case TARGET_WAITKIND_EXECD
:
2717 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
2719 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2721 context_switch (ecs
->ptid
);
2722 reinit_frame_cache ();
2725 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2727 /* This causes the eventpoints and symbol table to be reset.
2728 Must do this now, before trying to determine whether to
2730 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
2732 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2733 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2735 /* Note that this may be referenced from inside
2736 bpstat_stop_status above, through inferior_has_execd. */
2737 xfree (ecs
->ws
.value
.execd_pathname
);
2738 ecs
->ws
.value
.execd_pathname
= NULL
;
2740 /* If no catchpoint triggered for this, then keep going. */
2741 if (ecs
->random_signal
)
2743 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2747 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2748 goto process_event_stop_test
;
2750 /* Be careful not to try to gather much state about a thread
2751 that's in a syscall. It's frequently a losing proposition. */
2752 case TARGET_WAITKIND_SYSCALL_ENTRY
:
2754 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2755 /* Getting the current syscall number */
2756 if (deal_with_syscall_event (ecs
) != 0)
2758 goto process_event_stop_test
;
2761 /* Before examining the threads further, step this thread to
2762 get it entirely out of the syscall. (We get notice of the
2763 event when the thread is just on the verge of exiting a
2764 syscall. Stepping one instruction seems to get it back
2766 case TARGET_WAITKIND_SYSCALL_RETURN
:
2768 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2769 if (deal_with_syscall_event (ecs
) != 0)
2771 goto process_event_stop_test
;
2774 case TARGET_WAITKIND_STOPPED
:
2776 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
2777 ecs
->event_thread
->stop_signal
= ecs
->ws
.value
.sig
;
2780 case TARGET_WAITKIND_NO_HISTORY
:
2781 /* Reverse execution: target ran out of history info. */
2782 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2783 print_stop_reason (NO_HISTORY
, 0);
2784 stop_stepping (ecs
);
2787 /* We had an event in the inferior, but we are not interested
2788 in handling it at this level. The lower layers have already
2789 done what needs to be done, if anything.
2791 One of the possible circumstances for this is when the
2792 inferior produces output for the console. The inferior has
2793 not stopped, and we are ignoring the event. Another possible
2794 circumstance is any event which the lower level knows will be
2795 reported multiple times without an intervening resume. */
2796 case TARGET_WAITKIND_IGNORE
:
2798 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2799 prepare_to_wait (ecs
);
2803 if (ecs
->new_thread_event
)
2806 /* Non-stop assumes that the target handles adding new threads
2807 to the thread list. */
2808 internal_error (__FILE__
, __LINE__
, "\
2809 targets should add new threads to the thread list themselves in non-stop mode.");
2811 /* We may want to consider not doing a resume here in order to
2812 give the user a chance to play with the new thread. It might
2813 be good to make that a user-settable option. */
2815 /* At this point, all threads are stopped (happens automatically
2816 in either the OS or the native code). Therefore we need to
2817 continue all threads in order to make progress. */
2819 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2820 context_switch (ecs
->ptid
);
2821 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
2822 prepare_to_wait (ecs
);
2826 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
2828 /* Do we need to clean up the state of a thread that has
2829 completed a displaced single-step? (Doing so usually affects
2830 the PC, so do it here, before we set stop_pc.) */
2831 displaced_step_fixup (ecs
->ptid
, ecs
->event_thread
->stop_signal
);
2833 /* If we either finished a single-step or hit a breakpoint, but
2834 the user wanted this thread to be stopped, pretend we got a
2835 SIG0 (generic unsignaled stop). */
2837 if (ecs
->event_thread
->stop_requested
2838 && ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2839 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2842 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2846 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
2847 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2849 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
2850 paddress (gdbarch
, stop_pc
));
2851 if (target_stopped_by_watchpoint ())
2854 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
2856 if (target_stopped_data_address (¤t_target
, &addr
))
2857 fprintf_unfiltered (gdb_stdlog
,
2858 "infrun: stopped data address = %s\n",
2859 paddress (gdbarch
, addr
));
2861 fprintf_unfiltered (gdb_stdlog
,
2862 "infrun: (no data address available)\n");
2866 if (stepping_past_singlestep_breakpoint
)
2868 gdb_assert (singlestep_breakpoints_inserted_p
);
2869 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
2870 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
2872 stepping_past_singlestep_breakpoint
= 0;
2874 /* We've either finished single-stepping past the single-step
2875 breakpoint, or stopped for some other reason. It would be nice if
2876 we could tell, but we can't reliably. */
2877 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2880 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
2881 /* Pull the single step breakpoints out of the target. */
2882 remove_single_step_breakpoints ();
2883 singlestep_breakpoints_inserted_p
= 0;
2885 ecs
->random_signal
= 0;
2886 ecs
->event_thread
->trap_expected
= 0;
2888 context_switch (saved_singlestep_ptid
);
2889 if (deprecated_context_hook
)
2890 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2892 resume (1, TARGET_SIGNAL_0
);
2893 prepare_to_wait (ecs
);
2898 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
2900 /* In non-stop mode, there's never a deferred_step_ptid set. */
2901 gdb_assert (!non_stop
);
2903 /* If we stopped for some other reason than single-stepping, ignore
2904 the fact that we were supposed to switch back. */
2905 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2908 fprintf_unfiltered (gdb_stdlog
,
2909 "infrun: handling deferred step\n");
2911 /* Pull the single step breakpoints out of the target. */
2912 if (singlestep_breakpoints_inserted_p
)
2914 remove_single_step_breakpoints ();
2915 singlestep_breakpoints_inserted_p
= 0;
2918 /* Note: We do not call context_switch at this point, as the
2919 context is already set up for stepping the original thread. */
2920 switch_to_thread (deferred_step_ptid
);
2921 deferred_step_ptid
= null_ptid
;
2922 /* Suppress spurious "Switching to ..." message. */
2923 previous_inferior_ptid
= inferior_ptid
;
2925 resume (1, TARGET_SIGNAL_0
);
2926 prepare_to_wait (ecs
);
2930 deferred_step_ptid
= null_ptid
;
2933 /* See if a thread hit a thread-specific breakpoint that was meant for
2934 another thread. If so, then step that thread past the breakpoint,
2937 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2939 int thread_hop_needed
= 0;
2941 /* Check if a regular breakpoint has been hit before checking
2942 for a potential single step breakpoint. Otherwise, GDB will
2943 not see this breakpoint hit when stepping onto breakpoints. */
2944 if (regular_breakpoint_inserted_here_p (stop_pc
))
2946 ecs
->random_signal
= 0;
2947 if (!breakpoint_thread_match (stop_pc
, ecs
->ptid
))
2948 thread_hop_needed
= 1;
2950 else if (singlestep_breakpoints_inserted_p
)
2952 /* We have not context switched yet, so this should be true
2953 no matter which thread hit the singlestep breakpoint. */
2954 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
2956 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
2958 target_pid_to_str (ecs
->ptid
));
2960 ecs
->random_signal
= 0;
2961 /* The call to in_thread_list is necessary because PTIDs sometimes
2962 change when we go from single-threaded to multi-threaded. If
2963 the singlestep_ptid is still in the list, assume that it is
2964 really different from ecs->ptid. */
2965 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
2966 && in_thread_list (singlestep_ptid
))
2968 /* If the PC of the thread we were trying to single-step
2969 has changed, discard this event (which we were going
2970 to ignore anyway), and pretend we saw that thread
2971 trap. This prevents us continuously moving the
2972 single-step breakpoint forward, one instruction at a
2973 time. If the PC has changed, then the thread we were
2974 trying to single-step has trapped or been signalled,
2975 but the event has not been reported to GDB yet.
2977 There might be some cases where this loses signal
2978 information, if a signal has arrived at exactly the
2979 same time that the PC changed, but this is the best
2980 we can do with the information available. Perhaps we
2981 should arrange to report all events for all threads
2982 when they stop, or to re-poll the remote looking for
2983 this particular thread (i.e. temporarily enable
2986 CORE_ADDR new_singlestep_pc
2987 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
2989 if (new_singlestep_pc
!= singlestep_pc
)
2991 enum target_signal stop_signal
;
2994 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
2995 " but expected thread advanced also\n");
2997 /* The current context still belongs to
2998 singlestep_ptid. Don't swap here, since that's
2999 the context we want to use. Just fudge our
3000 state and continue. */
3001 stop_signal
= ecs
->event_thread
->stop_signal
;
3002 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3003 ecs
->ptid
= singlestep_ptid
;
3004 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3005 ecs
->event_thread
->stop_signal
= stop_signal
;
3006 stop_pc
= new_singlestep_pc
;
3011 fprintf_unfiltered (gdb_stdlog
,
3012 "infrun: unexpected thread\n");
3014 thread_hop_needed
= 1;
3015 stepping_past_singlestep_breakpoint
= 1;
3016 saved_singlestep_ptid
= singlestep_ptid
;
3021 if (thread_hop_needed
)
3023 struct regcache
*thread_regcache
;
3024 int remove_status
= 0;
3027 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3029 /* Switch context before touching inferior memory, the
3030 previous thread may have exited. */
3031 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3032 context_switch (ecs
->ptid
);
3034 /* Saw a breakpoint, but it was hit by the wrong thread.
3037 if (singlestep_breakpoints_inserted_p
)
3039 /* Pull the single step breakpoints out of the target. */
3040 remove_single_step_breakpoints ();
3041 singlestep_breakpoints_inserted_p
= 0;
3044 /* If the arch can displace step, don't remove the
3046 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3047 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3048 remove_status
= remove_breakpoints ();
3050 /* Did we fail to remove breakpoints? If so, try
3051 to set the PC past the bp. (There's at least
3052 one situation in which we can fail to remove
3053 the bp's: On HP-UX's that use ttrace, we can't
3054 change the address space of a vforking child
3055 process until the child exits (well, okay, not
3056 then either :-) or execs. */
3057 if (remove_status
!= 0)
3058 error (_("Cannot step over breakpoint hit in wrong thread"));
3063 /* Only need to require the next event from this
3064 thread in all-stop mode. */
3065 waiton_ptid
= ecs
->ptid
;
3066 infwait_state
= infwait_thread_hop_state
;
3069 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3074 else if (singlestep_breakpoints_inserted_p
)
3076 sw_single_step_trap_p
= 1;
3077 ecs
->random_signal
= 0;
3081 ecs
->random_signal
= 1;
3083 /* See if something interesting happened to the non-current thread. If
3084 so, then switch to that thread. */
3085 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3088 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3090 context_switch (ecs
->ptid
);
3092 if (deprecated_context_hook
)
3093 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3096 /* At this point, get hold of the now-current thread's frame. */
3097 frame
= get_current_frame ();
3098 gdbarch
= get_frame_arch (frame
);
3100 if (singlestep_breakpoints_inserted_p
)
3102 /* Pull the single step breakpoints out of the target. */
3103 remove_single_step_breakpoints ();
3104 singlestep_breakpoints_inserted_p
= 0;
3107 if (stepped_after_stopped_by_watchpoint
)
3108 stopped_by_watchpoint
= 0;
3110 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
3112 /* If necessary, step over this watchpoint. We'll be back to display
3114 if (stopped_by_watchpoint
3115 && (target_have_steppable_watchpoint
3116 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
3118 /* At this point, we are stopped at an instruction which has
3119 attempted to write to a piece of memory under control of
3120 a watchpoint. The instruction hasn't actually executed
3121 yet. If we were to evaluate the watchpoint expression
3122 now, we would get the old value, and therefore no change
3123 would seem to have occurred.
3125 In order to make watchpoints work `right', we really need
3126 to complete the memory write, and then evaluate the
3127 watchpoint expression. We do this by single-stepping the
3130 It may not be necessary to disable the watchpoint to stop over
3131 it. For example, the PA can (with some kernel cooperation)
3132 single step over a watchpoint without disabling the watchpoint.
3134 It is far more common to need to disable a watchpoint to step
3135 the inferior over it. If we have non-steppable watchpoints,
3136 we must disable the current watchpoint; it's simplest to
3137 disable all watchpoints and breakpoints. */
3140 if (!target_have_steppable_watchpoint
)
3141 remove_breakpoints ();
3143 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
3144 target_resume (ecs
->ptid
, hw_step
, TARGET_SIGNAL_0
);
3145 waiton_ptid
= ecs
->ptid
;
3146 if (target_have_steppable_watchpoint
)
3147 infwait_state
= infwait_step_watch_state
;
3149 infwait_state
= infwait_nonstep_watch_state
;
3150 prepare_to_wait (ecs
);
3154 ecs
->stop_func_start
= 0;
3155 ecs
->stop_func_end
= 0;
3156 ecs
->stop_func_name
= 0;
3157 /* Don't care about return value; stop_func_start and stop_func_name
3158 will both be 0 if it doesn't work. */
3159 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3160 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3161 ecs
->stop_func_start
3162 += gdbarch_deprecated_function_start_offset (gdbarch
);
3163 ecs
->event_thread
->stepping_over_breakpoint
= 0;
3164 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
3165 ecs
->event_thread
->stop_step
= 0;
3166 stop_print_frame
= 1;
3167 ecs
->random_signal
= 0;
3168 stopped_by_random_signal
= 0;
3170 /* Hide inlined functions starting here, unless we just performed stepi or
3171 nexti. After stepi and nexti, always show the innermost frame (not any
3172 inline function call sites). */
3173 if (ecs
->event_thread
->step_range_end
!= 1)
3174 skip_inline_frames (ecs
->ptid
);
3176 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3177 && ecs
->event_thread
->trap_expected
3178 && gdbarch_single_step_through_delay_p (gdbarch
)
3179 && currently_stepping (ecs
->event_thread
))
3181 /* We're trying to step off a breakpoint. Turns out that we're
3182 also on an instruction that needs to be stepped multiple
3183 times before it's been fully executing. E.g., architectures
3184 with a delay slot. It needs to be stepped twice, once for
3185 the instruction and once for the delay slot. */
3186 int step_through_delay
3187 = gdbarch_single_step_through_delay (gdbarch
, frame
);
3188 if (debug_infrun
&& step_through_delay
)
3189 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
3190 if (ecs
->event_thread
->step_range_end
== 0 && step_through_delay
)
3192 /* The user issued a continue when stopped at a breakpoint.
3193 Set up for another trap and get out of here. */
3194 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3198 else if (step_through_delay
)
3200 /* The user issued a step when stopped at a breakpoint.
3201 Maybe we should stop, maybe we should not - the delay
3202 slot *might* correspond to a line of source. In any
3203 case, don't decide that here, just set
3204 ecs->stepping_over_breakpoint, making sure we
3205 single-step again before breakpoints are re-inserted. */
3206 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3210 /* Look at the cause of the stop, and decide what to do.
3211 The alternatives are:
3212 1) stop_stepping and return; to really stop and return to the debugger,
3213 2) keep_going and return to start up again
3214 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
3215 3) set ecs->random_signal to 1, and the decision between 1 and 2
3216 will be made according to the signal handling tables. */
3218 /* First, distinguish signals caused by the debugger from signals
3219 that have to do with the program's own actions. Note that
3220 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3221 on the operating system version. Here we detect when a SIGILL or
3222 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3223 something similar for SIGSEGV, since a SIGSEGV will be generated
3224 when we're trying to execute a breakpoint instruction on a
3225 non-executable stack. This happens for call dummy breakpoints
3226 for architectures like SPARC that place call dummies on the
3229 If we're doing a displaced step past a breakpoint, then the
3230 breakpoint is always inserted at the original instruction;
3231 non-standard signals can't be explained by the breakpoint. */
3232 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3233 || (! ecs
->event_thread
->trap_expected
3234 && breakpoint_inserted_here_p (stop_pc
)
3235 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_ILL
3236 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_SEGV
3237 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_EMT
))
3238 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3239 || stop_soon
== STOP_QUIETLY_REMOTE
)
3241 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
3244 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
3245 stop_print_frame
= 0;
3246 stop_stepping (ecs
);
3250 /* This is originated from start_remote(), start_inferior() and
3251 shared libraries hook functions. */
3252 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
3255 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3256 stop_stepping (ecs
);
3260 /* This originates from attach_command(). We need to overwrite
3261 the stop_signal here, because some kernels don't ignore a
3262 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
3263 See more comments in inferior.h. On the other hand, if we
3264 get a non-SIGSTOP, report it to the user - assume the backend
3265 will handle the SIGSTOP if it should show up later.
3267 Also consider that the attach is complete when we see a
3268 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
3269 target extended-remote report it instead of a SIGSTOP
3270 (e.g. gdbserver). We already rely on SIGTRAP being our
3271 signal, so this is no exception.
3273 Also consider that the attach is complete when we see a
3274 TARGET_SIGNAL_0. In non-stop mode, GDB will explicitly tell
3275 the target to stop all threads of the inferior, in case the
3276 low level attach operation doesn't stop them implicitly. If
3277 they weren't stopped implicitly, then the stub will report a
3278 TARGET_SIGNAL_0, meaning: stopped for no particular reason
3279 other than GDB's request. */
3280 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3281 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_STOP
3282 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3283 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_0
))
3285 stop_stepping (ecs
);
3286 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3290 /* See if there is a breakpoint at the current PC. */
3291 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
3293 /* Following in case break condition called a
3295 stop_print_frame
= 1;
3297 /* NOTE: cagney/2003-03-29: These two checks for a random signal
3298 at one stage in the past included checks for an inferior
3299 function call's call dummy's return breakpoint. The original
3300 comment, that went with the test, read:
3302 ``End of a stack dummy. Some systems (e.g. Sony news) give
3303 another signal besides SIGTRAP, so check here as well as
3306 If someone ever tries to get call dummys on a
3307 non-executable stack to work (where the target would stop
3308 with something like a SIGSEGV), then those tests might need
3309 to be re-instated. Given, however, that the tests were only
3310 enabled when momentary breakpoints were not being used, I
3311 suspect that it won't be the case.
3313 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
3314 be necessary for call dummies on a non-executable stack on
3317 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
3319 = !(bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
)
3320 || ecs
->event_thread
->trap_expected
3321 || (ecs
->event_thread
->step_range_end
3322 && ecs
->event_thread
->step_resume_breakpoint
== NULL
));
3325 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
3326 if (!ecs
->random_signal
)
3327 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
3331 /* When we reach this point, we've pretty much decided
3332 that the reason for stopping must've been a random
3333 (unexpected) signal. */
3336 ecs
->random_signal
= 1;
3338 process_event_stop_test
:
3340 /* Re-fetch current thread's frame in case we did a
3341 "goto process_event_stop_test" above. */
3342 frame
= get_current_frame ();
3343 gdbarch
= get_frame_arch (frame
);
3345 /* For the program's own signals, act according to
3346 the signal handling tables. */
3348 if (ecs
->random_signal
)
3350 /* Signal not for debugging purposes. */
3354 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
3355 ecs
->event_thread
->stop_signal
);
3357 stopped_by_random_signal
= 1;
3359 if (signal_print
[ecs
->event_thread
->stop_signal
])
3362 target_terminal_ours_for_output ();
3363 print_stop_reason (SIGNAL_RECEIVED
, ecs
->event_thread
->stop_signal
);
3365 /* Always stop on signals if we're either just gaining control
3366 of the program, or the user explicitly requested this thread
3367 to remain stopped. */
3368 if (stop_soon
!= NO_STOP_QUIETLY
3369 || ecs
->event_thread
->stop_requested
3370 || signal_stop_state (ecs
->event_thread
->stop_signal
))
3372 stop_stepping (ecs
);
3375 /* If not going to stop, give terminal back
3376 if we took it away. */
3378 target_terminal_inferior ();
3380 /* Clear the signal if it should not be passed. */
3381 if (signal_program
[ecs
->event_thread
->stop_signal
] == 0)
3382 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3384 if (ecs
->event_thread
->prev_pc
== stop_pc
3385 && ecs
->event_thread
->trap_expected
3386 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
3388 /* We were just starting a new sequence, attempting to
3389 single-step off of a breakpoint and expecting a SIGTRAP.
3390 Instead this signal arrives. This signal will take us out
3391 of the stepping range so GDB needs to remember to, when
3392 the signal handler returns, resume stepping off that
3394 /* To simplify things, "continue" is forced to use the same
3395 code paths as single-step - set a breakpoint at the
3396 signal return address and then, once hit, step off that
3399 fprintf_unfiltered (gdb_stdlog
,
3400 "infrun: signal arrived while stepping over "
3403 insert_step_resume_breakpoint_at_frame (frame
);
3404 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
3409 if (ecs
->event_thread
->step_range_end
!= 0
3410 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_0
3411 && (ecs
->event_thread
->step_range_start
<= stop_pc
3412 && stop_pc
< ecs
->event_thread
->step_range_end
)
3413 && frame_id_eq (get_stack_frame_id (frame
),
3414 ecs
->event_thread
->step_stack_frame_id
)
3415 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
3417 /* The inferior is about to take a signal that will take it
3418 out of the single step range. Set a breakpoint at the
3419 current PC (which is presumably where the signal handler
3420 will eventually return) and then allow the inferior to
3423 Note that this is only needed for a signal delivered
3424 while in the single-step range. Nested signals aren't a
3425 problem as they eventually all return. */
3427 fprintf_unfiltered (gdb_stdlog
,
3428 "infrun: signal may take us out of "
3429 "single-step range\n");
3431 insert_step_resume_breakpoint_at_frame (frame
);
3436 /* Note: step_resume_breakpoint may be non-NULL. This occures
3437 when either there's a nested signal, or when there's a
3438 pending signal enabled just as the signal handler returns
3439 (leaving the inferior at the step-resume-breakpoint without
3440 actually executing it). Either way continue until the
3441 breakpoint is really hit. */
3446 /* Handle cases caused by hitting a breakpoint. */
3448 CORE_ADDR jmp_buf_pc
;
3449 struct bpstat_what what
;
3451 what
= bpstat_what (ecs
->event_thread
->stop_bpstat
);
3453 if (what
.call_dummy
)
3455 stop_stack_dummy
= 1;
3458 switch (what
.main_action
)
3460 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
3461 /* If we hit the breakpoint at longjmp while stepping, we
3462 install a momentary breakpoint at the target of the
3466 fprintf_unfiltered (gdb_stdlog
,
3467 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
3469 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3471 if (!gdbarch_get_longjmp_target_p (gdbarch
)
3472 || !gdbarch_get_longjmp_target (gdbarch
, frame
, &jmp_buf_pc
))
3475 fprintf_unfiltered (gdb_stdlog
, "\
3476 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
3481 /* We're going to replace the current step-resume breakpoint
3482 with a longjmp-resume breakpoint. */
3483 delete_step_resume_breakpoint (ecs
->event_thread
);
3485 /* Insert a breakpoint at resume address. */
3486 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
3491 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
3493 fprintf_unfiltered (gdb_stdlog
,
3494 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
3496 gdb_assert (ecs
->event_thread
->step_resume_breakpoint
!= NULL
);
3497 delete_step_resume_breakpoint (ecs
->event_thread
);
3499 ecs
->event_thread
->stop_step
= 1;
3500 print_stop_reason (END_STEPPING_RANGE
, 0);
3501 stop_stepping (ecs
);
3504 case BPSTAT_WHAT_SINGLE
:
3506 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
3507 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3508 /* Still need to check other stuff, at least the case
3509 where we are stepping and step out of the right range. */
3512 case BPSTAT_WHAT_STOP_NOISY
:
3514 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
3515 stop_print_frame
= 1;
3517 /* We are about to nuke the step_resume_breakpointt via the
3518 cleanup chain, so no need to worry about it here. */
3520 stop_stepping (ecs
);
3523 case BPSTAT_WHAT_STOP_SILENT
:
3525 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
3526 stop_print_frame
= 0;
3528 /* We are about to nuke the step_resume_breakpoin via the
3529 cleanup chain, so no need to worry about it here. */
3531 stop_stepping (ecs
);
3534 case BPSTAT_WHAT_STEP_RESUME
:
3536 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
3538 delete_step_resume_breakpoint (ecs
->event_thread
);
3539 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
3541 /* Back when the step-resume breakpoint was inserted, we
3542 were trying to single-step off a breakpoint. Go back
3544 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
3545 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3549 if (stop_pc
== ecs
->stop_func_start
3550 && execution_direction
== EXEC_REVERSE
)
3552 /* We are stepping over a function call in reverse, and
3553 just hit the step-resume breakpoint at the start
3554 address of the function. Go back to single-stepping,
3555 which should take us back to the function call. */
3556 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3562 case BPSTAT_WHAT_CHECK_SHLIBS
:
3565 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
3567 /* Check for any newly added shared libraries if we're
3568 supposed to be adding them automatically. Switch
3569 terminal for any messages produced by
3570 breakpoint_re_set. */
3571 target_terminal_ours_for_output ();
3572 /* NOTE: cagney/2003-11-25: Make certain that the target
3573 stack's section table is kept up-to-date. Architectures,
3574 (e.g., PPC64), use the section table to perform
3575 operations such as address => section name and hence
3576 require the table to contain all sections (including
3577 those found in shared libraries). */
3579 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
3581 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
3583 target_terminal_inferior ();
3585 /* If requested, stop when the dynamic linker notifies
3586 gdb of events. This allows the user to get control
3587 and place breakpoints in initializer routines for
3588 dynamically loaded objects (among other things). */
3589 if (stop_on_solib_events
|| stop_stack_dummy
)
3591 stop_stepping (ecs
);
3596 /* We want to step over this breakpoint, then keep going. */
3597 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3603 case BPSTAT_WHAT_CHECK_JIT
:
3605 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_JIT\n");
3607 /* Switch terminal for any messages produced by breakpoint_re_set. */
3608 target_terminal_ours_for_output ();
3610 jit_event_handler (gdbarch
);
3612 target_terminal_inferior ();
3614 /* We want to step over this breakpoint, then keep going. */
3615 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3619 case BPSTAT_WHAT_LAST
:
3620 /* Not a real code, but listed here to shut up gcc -Wall. */
3622 case BPSTAT_WHAT_KEEP_CHECKING
:
3627 /* We come here if we hit a breakpoint but should not
3628 stop for it. Possibly we also were stepping
3629 and should stop for that. So fall through and
3630 test for stepping. But, if not stepping,
3633 /* In all-stop mode, if we're currently stepping but have stopped in
3634 some other thread, we need to switch back to the stepped thread. */
3637 struct thread_info
*tp
;
3638 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
3642 /* However, if the current thread is blocked on some internal
3643 breakpoint, and we simply need to step over that breakpoint
3644 to get it going again, do that first. */
3645 if ((ecs
->event_thread
->trap_expected
3646 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
3647 || ecs
->event_thread
->stepping_over_breakpoint
)
3653 /* If the stepping thread exited, then don't try to switch
3654 back and resume it, which could fail in several different
3655 ways depending on the target. Instead, just keep going.
3657 We can find a stepping dead thread in the thread list in
3660 - The target supports thread exit events, and when the
3661 target tries to delete the thread from the thread list,
3662 inferior_ptid pointed at the exiting thread. In such
3663 case, calling delete_thread does not really remove the
3664 thread from the list; instead, the thread is left listed,
3665 with 'exited' state.
3667 - The target's debug interface does not support thread
3668 exit events, and so we have no idea whatsoever if the
3669 previously stepping thread is still alive. For that
3670 reason, we need to synchronously query the target
3672 if (is_exited (tp
->ptid
)
3673 || !target_thread_alive (tp
->ptid
))
3676 fprintf_unfiltered (gdb_stdlog
, "\
3677 infrun: not switching back to stepped thread, it has vanished\n");
3679 delete_thread (tp
->ptid
);
3684 /* Otherwise, we no longer expect a trap in the current thread.
3685 Clear the trap_expected flag before switching back -- this is
3686 what keep_going would do as well, if we called it. */
3687 ecs
->event_thread
->trap_expected
= 0;
3690 fprintf_unfiltered (gdb_stdlog
,
3691 "infrun: switching back to stepped thread\n");
3693 ecs
->event_thread
= tp
;
3694 ecs
->ptid
= tp
->ptid
;
3695 context_switch (ecs
->ptid
);
3701 /* Are we stepping to get the inferior out of the dynamic linker's
3702 hook (and possibly the dld itself) after catching a shlib
3704 if (ecs
->event_thread
->stepping_through_solib_after_catch
)
3706 #if defined(SOLIB_ADD)
3707 /* Have we reached our destination? If not, keep going. */
3708 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
3711 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
3712 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3718 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
3719 /* Else, stop and report the catchpoint(s) whose triggering
3720 caused us to begin stepping. */
3721 ecs
->event_thread
->stepping_through_solib_after_catch
= 0;
3722 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
3723 ecs
->event_thread
->stop_bpstat
3724 = bpstat_copy (ecs
->event_thread
->stepping_through_solib_catchpoints
);
3725 bpstat_clear (&ecs
->event_thread
->stepping_through_solib_catchpoints
);
3726 stop_print_frame
= 1;
3727 stop_stepping (ecs
);
3731 if (ecs
->event_thread
->step_resume_breakpoint
)
3734 fprintf_unfiltered (gdb_stdlog
,
3735 "infrun: step-resume breakpoint is inserted\n");
3737 /* Having a step-resume breakpoint overrides anything
3738 else having to do with stepping commands until
3739 that breakpoint is reached. */
3744 if (ecs
->event_thread
->step_range_end
== 0)
3747 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
3748 /* Likewise if we aren't even stepping. */
3753 /* If stepping through a line, keep going if still within it.
3755 Note that step_range_end is the address of the first instruction
3756 beyond the step range, and NOT the address of the last instruction
3759 Note also that during reverse execution, we may be stepping
3760 through a function epilogue and therefore must detect when
3761 the current-frame changes in the middle of a line. */
3763 if (stop_pc
>= ecs
->event_thread
->step_range_start
3764 && stop_pc
< ecs
->event_thread
->step_range_end
3765 && (execution_direction
!= EXEC_REVERSE
3766 || frame_id_eq (get_frame_id (frame
),
3767 ecs
->event_thread
->step_frame_id
)))
3771 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
3772 paddress (gdbarch
, ecs
->event_thread
->step_range_start
),
3773 paddress (gdbarch
, ecs
->event_thread
->step_range_end
));
3775 /* When stepping backward, stop at beginning of line range
3776 (unless it's the function entry point, in which case
3777 keep going back to the call point). */
3778 if (stop_pc
== ecs
->event_thread
->step_range_start
3779 && stop_pc
!= ecs
->stop_func_start
3780 && execution_direction
== EXEC_REVERSE
)
3782 ecs
->event_thread
->stop_step
= 1;
3783 print_stop_reason (END_STEPPING_RANGE
, 0);
3784 stop_stepping (ecs
);
3792 /* We stepped out of the stepping range. */
3794 /* If we are stepping at the source level and entered the runtime
3795 loader dynamic symbol resolution code...
3797 EXEC_FORWARD: we keep on single stepping until we exit the run
3798 time loader code and reach the callee's address.
3800 EXEC_REVERSE: we've already executed the callee (backward), and
3801 the runtime loader code is handled just like any other
3802 undebuggable function call. Now we need only keep stepping
3803 backward through the trampoline code, and that's handled further
3804 down, so there is nothing for us to do here. */
3806 if (execution_direction
!= EXEC_REVERSE
3807 && ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3808 && in_solib_dynsym_resolve_code (stop_pc
))
3810 CORE_ADDR pc_after_resolver
=
3811 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
3814 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
3816 if (pc_after_resolver
)
3818 /* Set up a step-resume breakpoint at the address
3819 indicated by SKIP_SOLIB_RESOLVER. */
3820 struct symtab_and_line sr_sal
;
3822 sr_sal
.pc
= pc_after_resolver
;
3824 insert_step_resume_breakpoint_at_sal (gdbarch
,
3825 sr_sal
, null_frame_id
);
3832 if (ecs
->event_thread
->step_range_end
!= 1
3833 && (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3834 || ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3835 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
3838 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
3839 /* The inferior, while doing a "step" or "next", has ended up in
3840 a signal trampoline (either by a signal being delivered or by
3841 the signal handler returning). Just single-step until the
3842 inferior leaves the trampoline (either by calling the handler
3848 /* Check for subroutine calls. The check for the current frame
3849 equalling the step ID is not necessary - the check of the
3850 previous frame's ID is sufficient - but it is a common case and
3851 cheaper than checking the previous frame's ID.
3853 NOTE: frame_id_eq will never report two invalid frame IDs as
3854 being equal, so to get into this block, both the current and
3855 previous frame must have valid frame IDs. */
3856 /* The outer_frame_id check is a heuristic to detect stepping
3857 through startup code. If we step over an instruction which
3858 sets the stack pointer from an invalid value to a valid value,
3859 we may detect that as a subroutine call from the mythical
3860 "outermost" function. This could be fixed by marking
3861 outermost frames as !stack_p,code_p,special_p. Then the
3862 initial outermost frame, before sp was valid, would
3863 have code_addr == &_start. See the commend in frame_id_eq
3865 if (!frame_id_eq (get_stack_frame_id (frame
),
3866 ecs
->event_thread
->step_stack_frame_id
)
3867 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
3868 ecs
->event_thread
->step_stack_frame_id
)
3869 && (!frame_id_eq (ecs
->event_thread
->step_stack_frame_id
,
3871 || step_start_function
!= find_pc_function (stop_pc
))))
3873 CORE_ADDR real_stop_pc
;
3876 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
3878 if ((ecs
->event_thread
->step_over_calls
== STEP_OVER_NONE
)
3879 || ((ecs
->event_thread
->step_range_end
== 1)
3880 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
3881 ecs
->stop_func_start
)))
3883 /* I presume that step_over_calls is only 0 when we're
3884 supposed to be stepping at the assembly language level
3885 ("stepi"). Just stop. */
3886 /* Also, maybe we just did a "nexti" inside a prolog, so we
3887 thought it was a subroutine call but it was not. Stop as
3889 /* And this works the same backward as frontward. MVS */
3890 ecs
->event_thread
->stop_step
= 1;
3891 print_stop_reason (END_STEPPING_RANGE
, 0);
3892 stop_stepping (ecs
);
3896 /* Reverse stepping through solib trampolines. */
3898 if (execution_direction
== EXEC_REVERSE
3899 && ecs
->event_thread
->step_over_calls
!= STEP_OVER_NONE
3900 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
3901 || (ecs
->stop_func_start
== 0
3902 && in_solib_dynsym_resolve_code (stop_pc
))))
3904 /* Any solib trampoline code can be handled in reverse
3905 by simply continuing to single-step. We have already
3906 executed the solib function (backwards), and a few
3907 steps will take us back through the trampoline to the
3913 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3915 /* We're doing a "next".
3917 Normal (forward) execution: set a breakpoint at the
3918 callee's return address (the address at which the caller
3921 Reverse (backward) execution. set the step-resume
3922 breakpoint at the start of the function that we just
3923 stepped into (backwards), and continue to there. When we
3924 get there, we'll need to single-step back to the caller. */
3926 if (execution_direction
== EXEC_REVERSE
)
3928 struct symtab_and_line sr_sal
;
3930 /* Normal function call return (static or dynamic). */
3932 sr_sal
.pc
= ecs
->stop_func_start
;
3933 insert_step_resume_breakpoint_at_sal (gdbarch
,
3934 sr_sal
, null_frame_id
);
3937 insert_step_resume_breakpoint_at_caller (frame
);
3943 /* If we are in a function call trampoline (a stub between the
3944 calling routine and the real function), locate the real
3945 function. That's what tells us (a) whether we want to step
3946 into it at all, and (b) what prologue we want to run to the
3947 end of, if we do step into it. */
3948 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
3949 if (real_stop_pc
== 0)
3950 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
3951 if (real_stop_pc
!= 0)
3952 ecs
->stop_func_start
= real_stop_pc
;
3954 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
3956 struct symtab_and_line sr_sal
;
3958 sr_sal
.pc
= ecs
->stop_func_start
;
3960 insert_step_resume_breakpoint_at_sal (gdbarch
,
3961 sr_sal
, null_frame_id
);
3966 /* If we have line number information for the function we are
3967 thinking of stepping into, step into it.
3969 If there are several symtabs at that PC (e.g. with include
3970 files), just want to know whether *any* of them have line
3971 numbers. find_pc_line handles this. */
3973 struct symtab_and_line tmp_sal
;
3975 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3976 if (tmp_sal
.line
!= 0)
3978 if (execution_direction
== EXEC_REVERSE
)
3979 handle_step_into_function_backward (gdbarch
, ecs
);
3981 handle_step_into_function (gdbarch
, ecs
);
3986 /* If we have no line number and the step-stop-if-no-debug is
3987 set, we stop the step so that the user has a chance to switch
3988 in assembly mode. */
3989 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3990 && step_stop_if_no_debug
)
3992 ecs
->event_thread
->stop_step
= 1;
3993 print_stop_reason (END_STEPPING_RANGE
, 0);
3994 stop_stepping (ecs
);
3998 if (execution_direction
== EXEC_REVERSE
)
4000 /* Set a breakpoint at callee's start address.
4001 From there we can step once and be back in the caller. */
4002 struct symtab_and_line sr_sal
;
4004 sr_sal
.pc
= ecs
->stop_func_start
;
4005 insert_step_resume_breakpoint_at_sal (gdbarch
,
4006 sr_sal
, null_frame_id
);
4009 /* Set a breakpoint at callee's return address (the address
4010 at which the caller will resume). */
4011 insert_step_resume_breakpoint_at_caller (frame
);
4017 /* Reverse stepping through solib trampolines. */
4019 if (execution_direction
== EXEC_REVERSE
4020 && ecs
->event_thread
->step_over_calls
!= STEP_OVER_NONE
)
4022 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4023 || (ecs
->stop_func_start
== 0
4024 && in_solib_dynsym_resolve_code (stop_pc
)))
4026 /* Any solib trampoline code can be handled in reverse
4027 by simply continuing to single-step. We have already
4028 executed the solib function (backwards), and a few
4029 steps will take us back through the trampoline to the
4034 else if (in_solib_dynsym_resolve_code (stop_pc
))
4036 /* Stepped backward into the solib dynsym resolver.
4037 Set a breakpoint at its start and continue, then
4038 one more step will take us out. */
4039 struct symtab_and_line sr_sal
;
4041 sr_sal
.pc
= ecs
->stop_func_start
;
4042 insert_step_resume_breakpoint_at_sal (gdbarch
,
4043 sr_sal
, null_frame_id
);
4049 /* If we're in the return path from a shared library trampoline,
4050 we want to proceed through the trampoline when stepping. */
4051 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4052 stop_pc
, ecs
->stop_func_name
))
4054 /* Determine where this trampoline returns. */
4055 CORE_ADDR real_stop_pc
;
4056 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4059 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
4061 /* Only proceed through if we know where it's going. */
4064 /* And put the step-breakpoint there and go until there. */
4065 struct symtab_and_line sr_sal
;
4067 init_sal (&sr_sal
); /* initialize to zeroes */
4068 sr_sal
.pc
= real_stop_pc
;
4069 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4071 /* Do not specify what the fp should be when we stop since
4072 on some machines the prologue is where the new fp value
4074 insert_step_resume_breakpoint_at_sal (gdbarch
,
4075 sr_sal
, null_frame_id
);
4077 /* Restart without fiddling with the step ranges or
4084 stop_pc_sal
= find_pc_line (stop_pc
, 0);
4086 /* NOTE: tausq/2004-05-24: This if block used to be done before all
4087 the trampoline processing logic, however, there are some trampolines
4088 that have no names, so we should do trampoline handling first. */
4089 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
4090 && ecs
->stop_func_name
== NULL
4091 && stop_pc_sal
.line
== 0)
4094 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
4096 /* The inferior just stepped into, or returned to, an
4097 undebuggable function (where there is no debugging information
4098 and no line number corresponding to the address where the
4099 inferior stopped). Since we want to skip this kind of code,
4100 we keep going until the inferior returns from this
4101 function - unless the user has asked us not to (via
4102 set step-mode) or we no longer know how to get back
4103 to the call site. */
4104 if (step_stop_if_no_debug
4105 || !frame_id_p (frame_unwind_caller_id (frame
)))
4107 /* If we have no line number and the step-stop-if-no-debug
4108 is set, we stop the step so that the user has a chance to
4109 switch in assembly mode. */
4110 ecs
->event_thread
->stop_step
= 1;
4111 print_stop_reason (END_STEPPING_RANGE
, 0);
4112 stop_stepping (ecs
);
4117 /* Set a breakpoint at callee's return address (the address
4118 at which the caller will resume). */
4119 insert_step_resume_breakpoint_at_caller (frame
);
4125 if (ecs
->event_thread
->step_range_end
== 1)
4127 /* It is stepi or nexti. We always want to stop stepping after
4130 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
4131 ecs
->event_thread
->stop_step
= 1;
4132 print_stop_reason (END_STEPPING_RANGE
, 0);
4133 stop_stepping (ecs
);
4137 if (stop_pc_sal
.line
== 0)
4139 /* We have no line number information. That means to stop
4140 stepping (does this always happen right after one instruction,
4141 when we do "s" in a function with no line numbers,
4142 or can this happen as a result of a return or longjmp?). */
4144 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
4145 ecs
->event_thread
->stop_step
= 1;
4146 print_stop_reason (END_STEPPING_RANGE
, 0);
4147 stop_stepping (ecs
);
4151 /* Look for "calls" to inlined functions, part one. If the inline
4152 frame machinery detected some skipped call sites, we have entered
4153 a new inline function. */
4155 if (frame_id_eq (get_frame_id (get_current_frame ()),
4156 ecs
->event_thread
->step_frame_id
)
4157 && inline_skipped_frames (ecs
->ptid
))
4159 struct symtab_and_line call_sal
;
4162 fprintf_unfiltered (gdb_stdlog
,
4163 "infrun: stepped into inlined function\n");
4165 find_frame_sal (get_current_frame (), &call_sal
);
4167 if (ecs
->event_thread
->step_over_calls
!= STEP_OVER_ALL
)
4169 /* For "step", we're going to stop. But if the call site
4170 for this inlined function is on the same source line as
4171 we were previously stepping, go down into the function
4172 first. Otherwise stop at the call site. */
4174 if (call_sal
.line
== ecs
->event_thread
->current_line
4175 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4176 step_into_inline_frame (ecs
->ptid
);
4178 ecs
->event_thread
->stop_step
= 1;
4179 print_stop_reason (END_STEPPING_RANGE
, 0);
4180 stop_stepping (ecs
);
4185 /* For "next", we should stop at the call site if it is on a
4186 different source line. Otherwise continue through the
4187 inlined function. */
4188 if (call_sal
.line
== ecs
->event_thread
->current_line
4189 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4193 ecs
->event_thread
->stop_step
= 1;
4194 print_stop_reason (END_STEPPING_RANGE
, 0);
4195 stop_stepping (ecs
);
4201 /* Look for "calls" to inlined functions, part two. If we are still
4202 in the same real function we were stepping through, but we have
4203 to go further up to find the exact frame ID, we are stepping
4204 through a more inlined call beyond its call site. */
4206 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
4207 && !frame_id_eq (get_frame_id (get_current_frame ()),
4208 ecs
->event_thread
->step_frame_id
)
4209 && stepped_in_from (get_current_frame (),
4210 ecs
->event_thread
->step_frame_id
))
4213 fprintf_unfiltered (gdb_stdlog
,
4214 "infrun: stepping through inlined function\n");
4216 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
4220 ecs
->event_thread
->stop_step
= 1;
4221 print_stop_reason (END_STEPPING_RANGE
, 0);
4222 stop_stepping (ecs
);
4227 if ((stop_pc
== stop_pc_sal
.pc
)
4228 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
4229 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
4231 /* We are at the start of a different line. So stop. Note that
4232 we don't stop if we step into the middle of a different line.
4233 That is said to make things like for (;;) statements work
4236 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
4237 ecs
->event_thread
->stop_step
= 1;
4238 print_stop_reason (END_STEPPING_RANGE
, 0);
4239 stop_stepping (ecs
);
4243 /* We aren't done stepping.
4245 Optimize by setting the stepping range to the line.
4246 (We might not be in the original line, but if we entered a
4247 new line in mid-statement, we continue stepping. This makes
4248 things like for(;;) statements work better.) */
4250 ecs
->event_thread
->step_range_start
= stop_pc_sal
.pc
;
4251 ecs
->event_thread
->step_range_end
= stop_pc_sal
.end
;
4252 set_step_info (frame
, stop_pc_sal
);
4255 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
4259 /* Is thread TP in the middle of single-stepping? */
4262 currently_stepping (struct thread_info
*tp
)
4264 return ((tp
->step_range_end
&& tp
->step_resume_breakpoint
== NULL
)
4265 || tp
->trap_expected
4266 || tp
->stepping_through_solib_after_catch
4267 || bpstat_should_step ());
4270 /* Returns true if any thread *but* the one passed in "data" is in the
4271 middle of stepping or of handling a "next". */
4274 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
4279 return (tp
->step_range_end
4280 || tp
->trap_expected
4281 || tp
->stepping_through_solib_after_catch
);
4284 /* Inferior has stepped into a subroutine call with source code that
4285 we should not step over. Do step to the first line of code in
4289 handle_step_into_function (struct gdbarch
*gdbarch
,
4290 struct execution_control_state
*ecs
)
4293 struct symtab_and_line stop_func_sal
, sr_sal
;
4295 s
= find_pc_symtab (stop_pc
);
4296 if (s
&& s
->language
!= language_asm
)
4297 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
4298 ecs
->stop_func_start
);
4300 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4301 /* Use the step_resume_break to step until the end of the prologue,
4302 even if that involves jumps (as it seems to on the vax under
4304 /* If the prologue ends in the middle of a source line, continue to
4305 the end of that source line (if it is still within the function).
4306 Otherwise, just go to end of prologue. */
4307 if (stop_func_sal
.end
4308 && stop_func_sal
.pc
!= ecs
->stop_func_start
4309 && stop_func_sal
.end
< ecs
->stop_func_end
)
4310 ecs
->stop_func_start
= stop_func_sal
.end
;
4312 /* Architectures which require breakpoint adjustment might not be able
4313 to place a breakpoint at the computed address. If so, the test
4314 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
4315 ecs->stop_func_start to an address at which a breakpoint may be
4316 legitimately placed.
4318 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
4319 made, GDB will enter an infinite loop when stepping through
4320 optimized code consisting of VLIW instructions which contain
4321 subinstructions corresponding to different source lines. On
4322 FR-V, it's not permitted to place a breakpoint on any but the
4323 first subinstruction of a VLIW instruction. When a breakpoint is
4324 set, GDB will adjust the breakpoint address to the beginning of
4325 the VLIW instruction. Thus, we need to make the corresponding
4326 adjustment here when computing the stop address. */
4328 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
4330 ecs
->stop_func_start
4331 = gdbarch_adjust_breakpoint_address (gdbarch
,
4332 ecs
->stop_func_start
);
4335 if (ecs
->stop_func_start
== stop_pc
)
4337 /* We are already there: stop now. */
4338 ecs
->event_thread
->stop_step
= 1;
4339 print_stop_reason (END_STEPPING_RANGE
, 0);
4340 stop_stepping (ecs
);
4345 /* Put the step-breakpoint there and go until there. */
4346 init_sal (&sr_sal
); /* initialize to zeroes */
4347 sr_sal
.pc
= ecs
->stop_func_start
;
4348 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
4350 /* Do not specify what the fp should be when we stop since on
4351 some machines the prologue is where the new fp value is
4353 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
4355 /* And make sure stepping stops right away then. */
4356 ecs
->event_thread
->step_range_end
= ecs
->event_thread
->step_range_start
;
4361 /* Inferior has stepped backward into a subroutine call with source
4362 code that we should not step over. Do step to the beginning of the
4363 last line of code in it. */
4366 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
4367 struct execution_control_state
*ecs
)
4370 struct symtab_and_line stop_func_sal
, sr_sal
;
4372 s
= find_pc_symtab (stop_pc
);
4373 if (s
&& s
->language
!= language_asm
)
4374 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
4375 ecs
->stop_func_start
);
4377 stop_func_sal
= find_pc_line (stop_pc
, 0);
4379 /* OK, we're just going to keep stepping here. */
4380 if (stop_func_sal
.pc
== stop_pc
)
4382 /* We're there already. Just stop stepping now. */
4383 ecs
->event_thread
->stop_step
= 1;
4384 print_stop_reason (END_STEPPING_RANGE
, 0);
4385 stop_stepping (ecs
);
4389 /* Else just reset the step range and keep going.
4390 No step-resume breakpoint, they don't work for
4391 epilogues, which can have multiple entry paths. */
4392 ecs
->event_thread
->step_range_start
= stop_func_sal
.pc
;
4393 ecs
->event_thread
->step_range_end
= stop_func_sal
.end
;
4399 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
4400 This is used to both functions and to skip over code. */
4403 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
4404 struct symtab_and_line sr_sal
,
4405 struct frame_id sr_id
)
4407 /* There should never be more than one step-resume or longjmp-resume
4408 breakpoint per thread, so we should never be setting a new
4409 step_resume_breakpoint when one is already active. */
4410 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
4413 fprintf_unfiltered (gdb_stdlog
,
4414 "infrun: inserting step-resume breakpoint at %s\n",
4415 paddress (gdbarch
, sr_sal
.pc
));
4417 inferior_thread ()->step_resume_breakpoint
4418 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, bp_step_resume
);
4421 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
4422 to skip a potential signal handler.
4424 This is called with the interrupted function's frame. The signal
4425 handler, when it returns, will resume the interrupted function at
4429 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
4431 struct symtab_and_line sr_sal
;
4432 struct gdbarch
*gdbarch
;
4434 gdb_assert (return_frame
!= NULL
);
4435 init_sal (&sr_sal
); /* initialize to zeros */
4437 gdbarch
= get_frame_arch (return_frame
);
4438 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
4439 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4441 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
4442 get_stack_frame_id (return_frame
));
4445 /* Similar to insert_step_resume_breakpoint_at_frame, except
4446 but a breakpoint at the previous frame's PC. This is used to
4447 skip a function after stepping into it (for "next" or if the called
4448 function has no debugging information).
4450 The current function has almost always been reached by single
4451 stepping a call or return instruction. NEXT_FRAME belongs to the
4452 current function, and the breakpoint will be set at the caller's
4455 This is a separate function rather than reusing
4456 insert_step_resume_breakpoint_at_frame in order to avoid
4457 get_prev_frame, which may stop prematurely (see the implementation
4458 of frame_unwind_caller_id for an example). */
4461 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
4463 struct symtab_and_line sr_sal
;
4464 struct gdbarch
*gdbarch
;
4466 /* We shouldn't have gotten here if we don't know where the call site
4468 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
4470 init_sal (&sr_sal
); /* initialize to zeros */
4472 gdbarch
= frame_unwind_caller_arch (next_frame
);
4473 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
4474 frame_unwind_caller_pc (next_frame
));
4475 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4477 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
4478 frame_unwind_caller_id (next_frame
));
4481 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
4482 new breakpoint at the target of a jmp_buf. The handling of
4483 longjmp-resume uses the same mechanisms used for handling
4484 "step-resume" breakpoints. */
4487 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
4489 /* There should never be more than one step-resume or longjmp-resume
4490 breakpoint per thread, so we should never be setting a new
4491 longjmp_resume_breakpoint when one is already active. */
4492 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
4495 fprintf_unfiltered (gdb_stdlog
,
4496 "infrun: inserting longjmp-resume breakpoint at %s\n",
4497 paddress (gdbarch
, pc
));
4499 inferior_thread ()->step_resume_breakpoint
=
4500 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
4504 stop_stepping (struct execution_control_state
*ecs
)
4507 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
4509 /* Let callers know we don't want to wait for the inferior anymore. */
4510 ecs
->wait_some_more
= 0;
4513 /* This function handles various cases where we need to continue
4514 waiting for the inferior. */
4515 /* (Used to be the keep_going: label in the old wait_for_inferior) */
4518 keep_going (struct execution_control_state
*ecs
)
4520 /* Save the pc before execution, to compare with pc after stop. */
4521 ecs
->event_thread
->prev_pc
4522 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4524 /* If we did not do break;, it means we should keep running the
4525 inferior and not return to debugger. */
4527 if (ecs
->event_thread
->trap_expected
4528 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
4530 /* We took a signal (which we are supposed to pass through to
4531 the inferior, else we'd not get here) and we haven't yet
4532 gotten our trap. Simply continue. */
4533 resume (currently_stepping (ecs
->event_thread
),
4534 ecs
->event_thread
->stop_signal
);
4538 /* Either the trap was not expected, but we are continuing
4539 anyway (the user asked that this signal be passed to the
4542 The signal was SIGTRAP, e.g. it was our signal, but we
4543 decided we should resume from it.
4545 We're going to run this baby now!
4547 Note that insert_breakpoints won't try to re-insert
4548 already inserted breakpoints. Therefore, we don't
4549 care if breakpoints were already inserted, or not. */
4551 if (ecs
->event_thread
->stepping_over_breakpoint
)
4553 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
4554 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
4555 /* Since we can't do a displaced step, we have to remove
4556 the breakpoint while we step it. To keep things
4557 simple, we remove them all. */
4558 remove_breakpoints ();
4562 struct gdb_exception e
;
4563 /* Stop stepping when inserting breakpoints
4565 TRY_CATCH (e
, RETURN_MASK_ERROR
)
4567 insert_breakpoints ();
4571 stop_stepping (ecs
);
4576 ecs
->event_thread
->trap_expected
= ecs
->event_thread
->stepping_over_breakpoint
;
4578 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
4579 specifies that such a signal should be delivered to the
4582 Typically, this would occure when a user is debugging a
4583 target monitor on a simulator: the target monitor sets a
4584 breakpoint; the simulator encounters this break-point and
4585 halts the simulation handing control to GDB; GDB, noteing
4586 that the break-point isn't valid, returns control back to the
4587 simulator; the simulator then delivers the hardware
4588 equivalent of a SIGNAL_TRAP to the program being debugged. */
4590 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
4591 && !signal_program
[ecs
->event_thread
->stop_signal
])
4592 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
4594 resume (currently_stepping (ecs
->event_thread
),
4595 ecs
->event_thread
->stop_signal
);
4598 prepare_to_wait (ecs
);
4601 /* This function normally comes after a resume, before
4602 handle_inferior_event exits. It takes care of any last bits of
4603 housekeeping, and sets the all-important wait_some_more flag. */
4606 prepare_to_wait (struct execution_control_state
*ecs
)
4609 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
4611 /* This is the old end of the while loop. Let everybody know we
4612 want to wait for the inferior some more and get called again
4614 ecs
->wait_some_more
= 1;
4617 /* Print why the inferior has stopped. We always print something when
4618 the inferior exits, or receives a signal. The rest of the cases are
4619 dealt with later on in normal_stop() and print_it_typical(). Ideally
4620 there should be a call to this function from handle_inferior_event()
4621 each time stop_stepping() is called.*/
4623 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
4625 switch (stop_reason
)
4627 case END_STEPPING_RANGE
:
4628 /* We are done with a step/next/si/ni command. */
4629 /* For now print nothing. */
4630 /* Print a message only if not in the middle of doing a "step n"
4631 operation for n > 1 */
4632 if (!inferior_thread ()->step_multi
4633 || !inferior_thread ()->stop_step
)
4634 if (ui_out_is_mi_like_p (uiout
))
4637 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
4640 /* The inferior was terminated by a signal. */
4641 annotate_signalled ();
4642 if (ui_out_is_mi_like_p (uiout
))
4645 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
4646 ui_out_text (uiout
, "\nProgram terminated with signal ");
4647 annotate_signal_name ();
4648 ui_out_field_string (uiout
, "signal-name",
4649 target_signal_to_name (stop_info
));
4650 annotate_signal_name_end ();
4651 ui_out_text (uiout
, ", ");
4652 annotate_signal_string ();
4653 ui_out_field_string (uiout
, "signal-meaning",
4654 target_signal_to_string (stop_info
));
4655 annotate_signal_string_end ();
4656 ui_out_text (uiout
, ".\n");
4657 ui_out_text (uiout
, "The program no longer exists.\n");
4660 /* The inferior program is finished. */
4661 annotate_exited (stop_info
);
4664 if (ui_out_is_mi_like_p (uiout
))
4665 ui_out_field_string (uiout
, "reason",
4666 async_reason_lookup (EXEC_ASYNC_EXITED
));
4667 ui_out_text (uiout
, "\nProgram exited with code ");
4668 ui_out_field_fmt (uiout
, "exit-code", "0%o",
4669 (unsigned int) stop_info
);
4670 ui_out_text (uiout
, ".\n");
4674 if (ui_out_is_mi_like_p (uiout
))
4677 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
4678 ui_out_text (uiout
, "\nProgram exited normally.\n");
4680 /* Support the --return-child-result option. */
4681 return_child_result_value
= stop_info
;
4683 case SIGNAL_RECEIVED
:
4684 /* Signal received. The signal table tells us to print about
4688 if (stop_info
== TARGET_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
4690 struct thread_info
*t
= inferior_thread ();
4692 ui_out_text (uiout
, "\n[");
4693 ui_out_field_string (uiout
, "thread-name",
4694 target_pid_to_str (t
->ptid
));
4695 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
4696 ui_out_text (uiout
, " stopped");
4700 ui_out_text (uiout
, "\nProgram received signal ");
4701 annotate_signal_name ();
4702 if (ui_out_is_mi_like_p (uiout
))
4704 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
4705 ui_out_field_string (uiout
, "signal-name",
4706 target_signal_to_name (stop_info
));
4707 annotate_signal_name_end ();
4708 ui_out_text (uiout
, ", ");
4709 annotate_signal_string ();
4710 ui_out_field_string (uiout
, "signal-meaning",
4711 target_signal_to_string (stop_info
));
4712 annotate_signal_string_end ();
4714 ui_out_text (uiout
, ".\n");
4717 /* Reverse execution: target ran out of history info. */
4718 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
4721 internal_error (__FILE__
, __LINE__
,
4722 _("print_stop_reason: unrecognized enum value"));
4728 /* Here to return control to GDB when the inferior stops for real.
4729 Print appropriate messages, remove breakpoints, give terminal our modes.
4731 STOP_PRINT_FRAME nonzero means print the executing frame
4732 (pc, function, args, file, line number and line text).
4733 BREAKPOINTS_FAILED nonzero means stop was due to error
4734 attempting to insert breakpoints. */
4739 struct target_waitstatus last
;
4741 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
4743 get_last_target_status (&last_ptid
, &last
);
4745 /* If an exception is thrown from this point on, make sure to
4746 propagate GDB's knowledge of the executing state to the
4747 frontend/user running state. A QUIT is an easy exception to see
4748 here, so do this before any filtered output. */
4750 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
4751 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
4752 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4753 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
4755 /* In non-stop mode, we don't want GDB to switch threads behind the
4756 user's back, to avoid races where the user is typing a command to
4757 apply to thread x, but GDB switches to thread y before the user
4758 finishes entering the command. */
4760 /* As with the notification of thread events, we want to delay
4761 notifying the user that we've switched thread context until
4762 the inferior actually stops.
4764 There's no point in saying anything if the inferior has exited.
4765 Note that SIGNALLED here means "exited with a signal", not
4766 "received a signal". */
4768 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
4769 && target_has_execution
4770 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
4771 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4773 target_terminal_ours_for_output ();
4774 printf_filtered (_("[Switching to %s]\n"),
4775 target_pid_to_str (inferior_ptid
));
4776 annotate_thread_changed ();
4777 previous_inferior_ptid
= inferior_ptid
;
4780 if (!breakpoints_always_inserted_mode () && target_has_execution
)
4782 if (remove_breakpoints ())
4784 target_terminal_ours_for_output ();
4785 printf_filtered (_("\
4786 Cannot remove breakpoints because program is no longer writable.\n\
4787 Further execution is probably impossible.\n"));
4791 /* If an auto-display called a function and that got a signal,
4792 delete that auto-display to avoid an infinite recursion. */
4794 if (stopped_by_random_signal
)
4795 disable_current_display ();
4797 /* Don't print a message if in the middle of doing a "step n"
4798 operation for n > 1 */
4799 if (target_has_execution
4800 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
4801 && last
.kind
!= TARGET_WAITKIND_EXITED
4802 && inferior_thread ()->step_multi
4803 && inferior_thread ()->stop_step
)
4806 target_terminal_ours ();
4808 /* Set the current source location. This will also happen if we
4809 display the frame below, but the current SAL will be incorrect
4810 during a user hook-stop function. */
4811 if (has_stack_frames () && !stop_stack_dummy
)
4812 set_current_sal_from_frame (get_current_frame (), 1);
4814 /* Let the user/frontend see the threads as stopped. */
4815 do_cleanups (old_chain
);
4817 /* Look up the hook_stop and run it (CLI internally handles problem
4818 of stop_command's pre-hook not existing). */
4820 catch_errors (hook_stop_stub
, stop_command
,
4821 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
4823 if (!has_stack_frames ())
4826 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
4827 || last
.kind
== TARGET_WAITKIND_EXITED
)
4830 /* Select innermost stack frame - i.e., current frame is frame 0,
4831 and current location is based on that.
4832 Don't do this on return from a stack dummy routine,
4833 or if the program has exited. */
4835 if (!stop_stack_dummy
)
4837 select_frame (get_current_frame ());
4839 /* Print current location without a level number, if
4840 we have changed functions or hit a breakpoint.
4841 Print source line if we have one.
4842 bpstat_print() contains the logic deciding in detail
4843 what to print, based on the event(s) that just occurred. */
4845 /* If --batch-silent is enabled then there's no need to print the current
4846 source location, and to try risks causing an error message about
4847 missing source files. */
4848 if (stop_print_frame
&& !batch_silent
)
4852 int do_frame_printing
= 1;
4853 struct thread_info
*tp
= inferior_thread ();
4855 bpstat_ret
= bpstat_print (tp
->stop_bpstat
);
4859 /* If we had hit a shared library event breakpoint,
4860 bpstat_print would print out this message. If we hit
4861 an OS-level shared library event, do the same
4863 if (last
.kind
== TARGET_WAITKIND_LOADED
)
4865 printf_filtered (_("Stopped due to shared library event\n"));
4866 source_flag
= SRC_LINE
; /* something bogus */
4867 do_frame_printing
= 0;
4871 /* FIXME: cagney/2002-12-01: Given that a frame ID does
4872 (or should) carry around the function and does (or
4873 should) use that when doing a frame comparison. */
4875 && frame_id_eq (tp
->step_frame_id
,
4876 get_frame_id (get_current_frame ()))
4877 && step_start_function
== find_pc_function (stop_pc
))
4878 source_flag
= SRC_LINE
; /* finished step, just print source line */
4880 source_flag
= SRC_AND_LOC
; /* print location and source line */
4882 case PRINT_SRC_AND_LOC
:
4883 source_flag
= SRC_AND_LOC
; /* print location and source line */
4885 case PRINT_SRC_ONLY
:
4886 source_flag
= SRC_LINE
;
4889 source_flag
= SRC_LINE
; /* something bogus */
4890 do_frame_printing
= 0;
4893 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
4896 /* The behavior of this routine with respect to the source
4898 SRC_LINE: Print only source line
4899 LOCATION: Print only location
4900 SRC_AND_LOC: Print location and source line */
4901 if (do_frame_printing
)
4902 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
4904 /* Display the auto-display expressions. */
4909 /* Save the function value return registers, if we care.
4910 We might be about to restore their previous contents. */
4911 if (inferior_thread ()->proceed_to_finish
)
4913 /* This should not be necessary. */
4915 regcache_xfree (stop_registers
);
4917 /* NB: The copy goes through to the target picking up the value of
4918 all the registers. */
4919 stop_registers
= regcache_dup (get_current_regcache ());
4922 if (stop_stack_dummy
)
4924 /* Pop the empty frame that contains the stack dummy.
4925 This also restores inferior state prior to the call
4926 (struct inferior_thread_state). */
4927 struct frame_info
*frame
= get_current_frame ();
4928 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
4930 /* frame_pop() calls reinit_frame_cache as the last thing it does
4931 which means there's currently no selected frame. We don't need
4932 to re-establish a selected frame if the dummy call returns normally,
4933 that will be done by restore_inferior_status. However, we do have
4934 to handle the case where the dummy call is returning after being
4935 stopped (e.g. the dummy call previously hit a breakpoint). We
4936 can't know which case we have so just always re-establish a
4937 selected frame here. */
4938 select_frame (get_current_frame ());
4942 annotate_stopped ();
4944 /* Suppress the stop observer if we're in the middle of:
4946 - a step n (n > 1), as there still more steps to be done.
4948 - a "finish" command, as the observer will be called in
4949 finish_command_continuation, so it can include the inferior
4950 function's return value.
4952 - calling an inferior function, as we pretend we inferior didn't
4953 run at all. The return value of the call is handled by the
4954 expression evaluator, through call_function_by_hand. */
4956 if (!target_has_execution
4957 || last
.kind
== TARGET_WAITKIND_SIGNALLED
4958 || last
.kind
== TARGET_WAITKIND_EXITED
4959 || (!inferior_thread ()->step_multi
4960 && !(inferior_thread ()->stop_bpstat
4961 && inferior_thread ()->proceed_to_finish
)
4962 && !inferior_thread ()->in_infcall
))
4964 if (!ptid_equal (inferior_ptid
, null_ptid
))
4965 observer_notify_normal_stop (inferior_thread ()->stop_bpstat
,
4968 observer_notify_normal_stop (NULL
, stop_print_frame
);
4971 if (target_has_execution
)
4973 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
4974 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4975 /* Delete the breakpoint we stopped at, if it wants to be deleted.
4976 Delete any breakpoint that is to be deleted at the next stop. */
4977 breakpoint_auto_delete (inferior_thread ()->stop_bpstat
);
4982 hook_stop_stub (void *cmd
)
4984 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
4989 signal_stop_state (int signo
)
4991 return signal_stop
[signo
];
4995 signal_print_state (int signo
)
4997 return signal_print
[signo
];
5001 signal_pass_state (int signo
)
5003 return signal_program
[signo
];
5007 signal_stop_update (int signo
, int state
)
5009 int ret
= signal_stop
[signo
];
5010 signal_stop
[signo
] = state
;
5015 signal_print_update (int signo
, int state
)
5017 int ret
= signal_print
[signo
];
5018 signal_print
[signo
] = state
;
5023 signal_pass_update (int signo
, int state
)
5025 int ret
= signal_program
[signo
];
5026 signal_program
[signo
] = state
;
5031 sig_print_header (void)
5033 printf_filtered (_("\
5034 Signal Stop\tPrint\tPass to program\tDescription\n"));
5038 sig_print_info (enum target_signal oursig
)
5040 const char *name
= target_signal_to_name (oursig
);
5041 int name_padding
= 13 - strlen (name
);
5043 if (name_padding
<= 0)
5046 printf_filtered ("%s", name
);
5047 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
5048 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
5049 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
5050 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
5051 printf_filtered ("%s\n", target_signal_to_string (oursig
));
5054 /* Specify how various signals in the inferior should be handled. */
5057 handle_command (char *args
, int from_tty
)
5060 int digits
, wordlen
;
5061 int sigfirst
, signum
, siglast
;
5062 enum target_signal oursig
;
5065 unsigned char *sigs
;
5066 struct cleanup
*old_chain
;
5070 error_no_arg (_("signal to handle"));
5073 /* Allocate and zero an array of flags for which signals to handle. */
5075 nsigs
= (int) TARGET_SIGNAL_LAST
;
5076 sigs
= (unsigned char *) alloca (nsigs
);
5077 memset (sigs
, 0, nsigs
);
5079 /* Break the command line up into args. */
5081 argv
= gdb_buildargv (args
);
5082 old_chain
= make_cleanup_freeargv (argv
);
5084 /* Walk through the args, looking for signal oursigs, signal names, and
5085 actions. Signal numbers and signal names may be interspersed with
5086 actions, with the actions being performed for all signals cumulatively
5087 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
5089 while (*argv
!= NULL
)
5091 wordlen
= strlen (*argv
);
5092 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
5096 sigfirst
= siglast
= -1;
5098 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
5100 /* Apply action to all signals except those used by the
5101 debugger. Silently skip those. */
5104 siglast
= nsigs
- 1;
5106 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
5108 SET_SIGS (nsigs
, sigs
, signal_stop
);
5109 SET_SIGS (nsigs
, sigs
, signal_print
);
5111 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
5113 UNSET_SIGS (nsigs
, sigs
, signal_program
);
5115 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
5117 SET_SIGS (nsigs
, sigs
, signal_print
);
5119 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
5121 SET_SIGS (nsigs
, sigs
, signal_program
);
5123 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
5125 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
5127 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
5129 SET_SIGS (nsigs
, sigs
, signal_program
);
5131 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
5133 UNSET_SIGS (nsigs
, sigs
, signal_print
);
5134 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
5136 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
5138 UNSET_SIGS (nsigs
, sigs
, signal_program
);
5140 else if (digits
> 0)
5142 /* It is numeric. The numeric signal refers to our own
5143 internal signal numbering from target.h, not to host/target
5144 signal number. This is a feature; users really should be
5145 using symbolic names anyway, and the common ones like
5146 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
5148 sigfirst
= siglast
= (int)
5149 target_signal_from_command (atoi (*argv
));
5150 if ((*argv
)[digits
] == '-')
5153 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
5155 if (sigfirst
> siglast
)
5157 /* Bet he didn't figure we'd think of this case... */
5165 oursig
= target_signal_from_name (*argv
);
5166 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
5168 sigfirst
= siglast
= (int) oursig
;
5172 /* Not a number and not a recognized flag word => complain. */
5173 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
5177 /* If any signal numbers or symbol names were found, set flags for
5178 which signals to apply actions to. */
5180 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
5182 switch ((enum target_signal
) signum
)
5184 case TARGET_SIGNAL_TRAP
:
5185 case TARGET_SIGNAL_INT
:
5186 if (!allsigs
&& !sigs
[signum
])
5188 if (query (_("%s is used by the debugger.\n\
5189 Are you sure you want to change it? "), target_signal_to_name ((enum target_signal
) signum
)))
5195 printf_unfiltered (_("Not confirmed, unchanged.\n"));
5196 gdb_flush (gdb_stdout
);
5200 case TARGET_SIGNAL_0
:
5201 case TARGET_SIGNAL_DEFAULT
:
5202 case TARGET_SIGNAL_UNKNOWN
:
5203 /* Make sure that "all" doesn't print these. */
5214 for (signum
= 0; signum
< nsigs
; signum
++)
5217 target_notice_signals (inferior_ptid
);
5221 /* Show the results. */
5222 sig_print_header ();
5223 for (; signum
< nsigs
; signum
++)
5225 sig_print_info (signum
);
5231 do_cleanups (old_chain
);
5235 xdb_handle_command (char *args
, int from_tty
)
5238 struct cleanup
*old_chain
;
5241 error_no_arg (_("xdb command"));
5243 /* Break the command line up into args. */
5245 argv
= gdb_buildargv (args
);
5246 old_chain
= make_cleanup_freeargv (argv
);
5247 if (argv
[1] != (char *) NULL
)
5252 bufLen
= strlen (argv
[0]) + 20;
5253 argBuf
= (char *) xmalloc (bufLen
);
5257 enum target_signal oursig
;
5259 oursig
= target_signal_from_name (argv
[0]);
5260 memset (argBuf
, 0, bufLen
);
5261 if (strcmp (argv
[1], "Q") == 0)
5262 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
5265 if (strcmp (argv
[1], "s") == 0)
5267 if (!signal_stop
[oursig
])
5268 sprintf (argBuf
, "%s %s", argv
[0], "stop");
5270 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
5272 else if (strcmp (argv
[1], "i") == 0)
5274 if (!signal_program
[oursig
])
5275 sprintf (argBuf
, "%s %s", argv
[0], "pass");
5277 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
5279 else if (strcmp (argv
[1], "r") == 0)
5281 if (!signal_print
[oursig
])
5282 sprintf (argBuf
, "%s %s", argv
[0], "print");
5284 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
5290 handle_command (argBuf
, from_tty
);
5292 printf_filtered (_("Invalid signal handling flag.\n"));
5297 do_cleanups (old_chain
);
5300 /* Print current contents of the tables set by the handle command.
5301 It is possible we should just be printing signals actually used
5302 by the current target (but for things to work right when switching
5303 targets, all signals should be in the signal tables). */
5306 signals_info (char *signum_exp
, int from_tty
)
5308 enum target_signal oursig
;
5309 sig_print_header ();
5313 /* First see if this is a symbol name. */
5314 oursig
= target_signal_from_name (signum_exp
);
5315 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
5317 /* No, try numeric. */
5319 target_signal_from_command (parse_and_eval_long (signum_exp
));
5321 sig_print_info (oursig
);
5325 printf_filtered ("\n");
5326 /* These ugly casts brought to you by the native VAX compiler. */
5327 for (oursig
= TARGET_SIGNAL_FIRST
;
5328 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
5329 oursig
= (enum target_signal
) ((int) oursig
+ 1))
5333 if (oursig
!= TARGET_SIGNAL_UNKNOWN
5334 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
5335 sig_print_info (oursig
);
5338 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
5341 /* The $_siginfo convenience variable is a bit special. We don't know
5342 for sure the type of the value until we actually have a chance to
5343 fetch the data. The type can change depending on gdbarch, so it it
5344 also dependent on which thread you have selected.
5346 1. making $_siginfo be an internalvar that creates a new value on
5349 2. making the value of $_siginfo be an lval_computed value. */
5351 /* This function implements the lval_computed support for reading a
5355 siginfo_value_read (struct value
*v
)
5357 LONGEST transferred
;
5360 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
5362 value_contents_all_raw (v
),
5364 TYPE_LENGTH (value_type (v
)));
5366 if (transferred
!= TYPE_LENGTH (value_type (v
)))
5367 error (_("Unable to read siginfo"));
5370 /* This function implements the lval_computed support for writing a
5374 siginfo_value_write (struct value
*v
, struct value
*fromval
)
5376 LONGEST transferred
;
5378 transferred
= target_write (¤t_target
,
5379 TARGET_OBJECT_SIGNAL_INFO
,
5381 value_contents_all_raw (fromval
),
5383 TYPE_LENGTH (value_type (fromval
)));
5385 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
5386 error (_("Unable to write siginfo"));
5389 static struct lval_funcs siginfo_value_funcs
=
5395 /* Return a new value with the correct type for the siginfo object of
5396 the current thread using architecture GDBARCH. Return a void value
5397 if there's no object available. */
5399 static struct value
*
5400 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
)
5402 if (target_has_stack
5403 && !ptid_equal (inferior_ptid
, null_ptid
)
5404 && gdbarch_get_siginfo_type_p (gdbarch
))
5406 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
5407 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
5410 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
5414 /* Inferior thread state.
5415 These are details related to the inferior itself, and don't include
5416 things like what frame the user had selected or what gdb was doing
5417 with the target at the time.
5418 For inferior function calls these are things we want to restore
5419 regardless of whether the function call successfully completes
5420 or the dummy frame has to be manually popped. */
5422 struct inferior_thread_state
5424 enum target_signal stop_signal
;
5426 struct regcache
*registers
;
5429 struct inferior_thread_state
*
5430 save_inferior_thread_state (void)
5432 struct inferior_thread_state
*inf_state
= XMALLOC (struct inferior_thread_state
);
5433 struct thread_info
*tp
= inferior_thread ();
5435 inf_state
->stop_signal
= tp
->stop_signal
;
5436 inf_state
->stop_pc
= stop_pc
;
5438 inf_state
->registers
= regcache_dup (get_current_regcache ());
5443 /* Restore inferior session state to INF_STATE. */
5446 restore_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5448 struct thread_info
*tp
= inferior_thread ();
5450 tp
->stop_signal
= inf_state
->stop_signal
;
5451 stop_pc
= inf_state
->stop_pc
;
5453 /* The inferior can be gone if the user types "print exit(0)"
5454 (and perhaps other times). */
5455 if (target_has_execution
)
5456 /* NB: The register write goes through to the target. */
5457 regcache_cpy (get_current_regcache (), inf_state
->registers
);
5458 regcache_xfree (inf_state
->registers
);
5463 do_restore_inferior_thread_state_cleanup (void *state
)
5465 restore_inferior_thread_state (state
);
5469 make_cleanup_restore_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5471 return make_cleanup (do_restore_inferior_thread_state_cleanup
, inf_state
);
5475 discard_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5477 regcache_xfree (inf_state
->registers
);
5482 get_inferior_thread_state_regcache (struct inferior_thread_state
*inf_state
)
5484 return inf_state
->registers
;
5487 /* Session related state for inferior function calls.
5488 These are the additional bits of state that need to be restored
5489 when an inferior function call successfully completes. */
5491 struct inferior_status
5495 int stop_stack_dummy
;
5496 int stopped_by_random_signal
;
5497 int stepping_over_breakpoint
;
5498 CORE_ADDR step_range_start
;
5499 CORE_ADDR step_range_end
;
5500 struct frame_id step_frame_id
;
5501 struct frame_id step_stack_frame_id
;
5502 enum step_over_calls_kind step_over_calls
;
5503 CORE_ADDR step_resume_break_address
;
5504 int stop_after_trap
;
5507 /* ID if the selected frame when the inferior function call was made. */
5508 struct frame_id selected_frame_id
;
5510 int proceed_to_finish
;
5514 /* Save all of the information associated with the inferior<==>gdb
5517 struct inferior_status
*
5518 save_inferior_status (void)
5520 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
5521 struct thread_info
*tp
= inferior_thread ();
5522 struct inferior
*inf
= current_inferior ();
5524 inf_status
->stop_step
= tp
->stop_step
;
5525 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
5526 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
5527 inf_status
->stepping_over_breakpoint
= tp
->trap_expected
;
5528 inf_status
->step_range_start
= tp
->step_range_start
;
5529 inf_status
->step_range_end
= tp
->step_range_end
;
5530 inf_status
->step_frame_id
= tp
->step_frame_id
;
5531 inf_status
->step_stack_frame_id
= tp
->step_stack_frame_id
;
5532 inf_status
->step_over_calls
= tp
->step_over_calls
;
5533 inf_status
->stop_after_trap
= stop_after_trap
;
5534 inf_status
->stop_soon
= inf
->stop_soon
;
5535 /* Save original bpstat chain here; replace it with copy of chain.
5536 If caller's caller is walking the chain, they'll be happier if we
5537 hand them back the original chain when restore_inferior_status is
5539 inf_status
->stop_bpstat
= tp
->stop_bpstat
;
5540 tp
->stop_bpstat
= bpstat_copy (tp
->stop_bpstat
);
5541 inf_status
->proceed_to_finish
= tp
->proceed_to_finish
;
5542 inf_status
->in_infcall
= tp
->in_infcall
;
5544 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
5550 restore_selected_frame (void *args
)
5552 struct frame_id
*fid
= (struct frame_id
*) args
;
5553 struct frame_info
*frame
;
5555 frame
= frame_find_by_id (*fid
);
5557 /* If inf_status->selected_frame_id is NULL, there was no previously
5561 warning (_("Unable to restore previously selected frame."));
5565 select_frame (frame
);
5570 /* Restore inferior session state to INF_STATUS. */
5573 restore_inferior_status (struct inferior_status
*inf_status
)
5575 struct thread_info
*tp
= inferior_thread ();
5576 struct inferior
*inf
= current_inferior ();
5578 tp
->stop_step
= inf_status
->stop_step
;
5579 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
5580 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
5581 tp
->trap_expected
= inf_status
->stepping_over_breakpoint
;
5582 tp
->step_range_start
= inf_status
->step_range_start
;
5583 tp
->step_range_end
= inf_status
->step_range_end
;
5584 tp
->step_frame_id
= inf_status
->step_frame_id
;
5585 tp
->step_stack_frame_id
= inf_status
->step_stack_frame_id
;
5586 tp
->step_over_calls
= inf_status
->step_over_calls
;
5587 stop_after_trap
= inf_status
->stop_after_trap
;
5588 inf
->stop_soon
= inf_status
->stop_soon
;
5589 bpstat_clear (&tp
->stop_bpstat
);
5590 tp
->stop_bpstat
= inf_status
->stop_bpstat
;
5591 inf_status
->stop_bpstat
= NULL
;
5592 tp
->proceed_to_finish
= inf_status
->proceed_to_finish
;
5593 tp
->in_infcall
= inf_status
->in_infcall
;
5595 if (target_has_stack
)
5597 /* The point of catch_errors is that if the stack is clobbered,
5598 walking the stack might encounter a garbage pointer and
5599 error() trying to dereference it. */
5601 (restore_selected_frame
, &inf_status
->selected_frame_id
,
5602 "Unable to restore previously selected frame:\n",
5603 RETURN_MASK_ERROR
) == 0)
5604 /* Error in restoring the selected frame. Select the innermost
5606 select_frame (get_current_frame ());
5613 do_restore_inferior_status_cleanup (void *sts
)
5615 restore_inferior_status (sts
);
5619 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
5621 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
5625 discard_inferior_status (struct inferior_status
*inf_status
)
5627 /* See save_inferior_status for info on stop_bpstat. */
5628 bpstat_clear (&inf_status
->stop_bpstat
);
5633 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
5635 struct target_waitstatus last
;
5638 get_last_target_status (&last_ptid
, &last
);
5640 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
5643 if (!ptid_equal (last_ptid
, pid
))
5646 *child_pid
= last
.value
.related_pid
;
5651 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
5653 struct target_waitstatus last
;
5656 get_last_target_status (&last_ptid
, &last
);
5658 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
5661 if (!ptid_equal (last_ptid
, pid
))
5664 *child_pid
= last
.value
.related_pid
;
5669 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
5671 struct target_waitstatus last
;
5674 get_last_target_status (&last_ptid
, &last
);
5676 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
5679 if (!ptid_equal (last_ptid
, pid
))
5682 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
5687 inferior_has_called_syscall (ptid_t pid
, int *syscall_number
)
5689 struct target_waitstatus last
;
5692 get_last_target_status (&last_ptid
, &last
);
5694 if (last
.kind
!= TARGET_WAITKIND_SYSCALL_ENTRY
&&
5695 last
.kind
!= TARGET_WAITKIND_SYSCALL_RETURN
)
5698 if (!ptid_equal (last_ptid
, pid
))
5701 *syscall_number
= last
.value
.syscall_number
;
5705 /* Oft used ptids */
5707 ptid_t minus_one_ptid
;
5709 /* Create a ptid given the necessary PID, LWP, and TID components. */
5712 ptid_build (int pid
, long lwp
, long tid
)
5722 /* Create a ptid from just a pid. */
5725 pid_to_ptid (int pid
)
5727 return ptid_build (pid
, 0, 0);
5730 /* Fetch the pid (process id) component from a ptid. */
5733 ptid_get_pid (ptid_t ptid
)
5738 /* Fetch the lwp (lightweight process) component from a ptid. */
5741 ptid_get_lwp (ptid_t ptid
)
5746 /* Fetch the tid (thread id) component from a ptid. */
5749 ptid_get_tid (ptid_t ptid
)
5754 /* ptid_equal() is used to test equality of two ptids. */
5757 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
5759 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
5760 && ptid1
.tid
== ptid2
.tid
);
5763 /* Returns true if PTID represents a process. */
5766 ptid_is_pid (ptid_t ptid
)
5768 if (ptid_equal (minus_one_ptid
, ptid
))
5770 if (ptid_equal (null_ptid
, ptid
))
5773 return (ptid_get_lwp (ptid
) == 0 && ptid_get_tid (ptid
) == 0);
5776 /* restore_inferior_ptid() will be used by the cleanup machinery
5777 to restore the inferior_ptid value saved in a call to
5778 save_inferior_ptid(). */
5781 restore_inferior_ptid (void *arg
)
5783 ptid_t
*saved_ptid_ptr
= arg
;
5784 inferior_ptid
= *saved_ptid_ptr
;
5788 /* Save the value of inferior_ptid so that it may be restored by a
5789 later call to do_cleanups(). Returns the struct cleanup pointer
5790 needed for later doing the cleanup. */
5793 save_inferior_ptid (void)
5795 ptid_t
*saved_ptid_ptr
;
5797 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
5798 *saved_ptid_ptr
= inferior_ptid
;
5799 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
5803 /* User interface for reverse debugging:
5804 Set exec-direction / show exec-direction commands
5805 (returns error unless target implements to_set_exec_direction method). */
5807 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
5808 static const char exec_forward
[] = "forward";
5809 static const char exec_reverse
[] = "reverse";
5810 static const char *exec_direction
= exec_forward
;
5811 static const char *exec_direction_names
[] = {
5818 set_exec_direction_func (char *args
, int from_tty
,
5819 struct cmd_list_element
*cmd
)
5821 if (target_can_execute_reverse
)
5823 if (!strcmp (exec_direction
, exec_forward
))
5824 execution_direction
= EXEC_FORWARD
;
5825 else if (!strcmp (exec_direction
, exec_reverse
))
5826 execution_direction
= EXEC_REVERSE
;
5831 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
5832 struct cmd_list_element
*cmd
, const char *value
)
5834 switch (execution_direction
) {
5836 fprintf_filtered (out
, _("Forward.\n"));
5839 fprintf_filtered (out
, _("Reverse.\n"));
5843 fprintf_filtered (out
,
5844 _("Forward (target `%s' does not support exec-direction).\n"),
5850 /* User interface for non-stop mode. */
5853 static int non_stop_1
= 0;
5856 set_non_stop (char *args
, int from_tty
,
5857 struct cmd_list_element
*c
)
5859 if (target_has_execution
)
5861 non_stop_1
= non_stop
;
5862 error (_("Cannot change this setting while the inferior is running."));
5865 non_stop
= non_stop_1
;
5869 show_non_stop (struct ui_file
*file
, int from_tty
,
5870 struct cmd_list_element
*c
, const char *value
)
5872 fprintf_filtered (file
,
5873 _("Controlling the inferior in non-stop mode is %s.\n"),
5878 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
5879 struct cmd_list_element
*c
, const char *value
)
5881 fprintf_filtered (file
, _("\
5882 Resuming the execution of threads of all processes is %s.\n"), value
);
5886 _initialize_infrun (void)
5890 struct cmd_list_element
*c
;
5892 add_info ("signals", signals_info
, _("\
5893 What debugger does when program gets various signals.\n\
5894 Specify a signal as argument to print info on that signal only."));
5895 add_info_alias ("handle", "signals", 0);
5897 add_com ("handle", class_run
, handle_command
, _("\
5898 Specify how to handle a signal.\n\
5899 Args are signals and actions to apply to those signals.\n\
5900 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
5901 from 1-15 are allowed for compatibility with old versions of GDB.\n\
5902 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
5903 The special arg \"all\" is recognized to mean all signals except those\n\
5904 used by the debugger, typically SIGTRAP and SIGINT.\n\
5905 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
5906 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
5907 Stop means reenter debugger if this signal happens (implies print).\n\
5908 Print means print a message if this signal happens.\n\
5909 Pass means let program see this signal; otherwise program doesn't know.\n\
5910 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
5911 Pass and Stop may be combined."));
5914 add_com ("lz", class_info
, signals_info
, _("\
5915 What debugger does when program gets various signals.\n\
5916 Specify a signal as argument to print info on that signal only."));
5917 add_com ("z", class_run
, xdb_handle_command
, _("\
5918 Specify how to handle a signal.\n\
5919 Args are signals and actions to apply to those signals.\n\
5920 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
5921 from 1-15 are allowed for compatibility with old versions of GDB.\n\
5922 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
5923 The special arg \"all\" is recognized to mean all signals except those\n\
5924 used by the debugger, typically SIGTRAP and SIGINT.\n\
5925 Recognized actions include \"s\" (toggles between stop and nostop), \n\
5926 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
5927 nopass), \"Q\" (noprint)\n\
5928 Stop means reenter debugger if this signal happens (implies print).\n\
5929 Print means print a message if this signal happens.\n\
5930 Pass means let program see this signal; otherwise program doesn't know.\n\
5931 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
5932 Pass and Stop may be combined."));
5936 stop_command
= add_cmd ("stop", class_obscure
,
5937 not_just_help_class_command
, _("\
5938 There is no `stop' command, but you can set a hook on `stop'.\n\
5939 This allows you to set a list of commands to be run each time execution\n\
5940 of the program stops."), &cmdlist
);
5942 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
5943 Set inferior debugging."), _("\
5944 Show inferior debugging."), _("\
5945 When non-zero, inferior specific debugging is enabled."),
5948 &setdebuglist
, &showdebuglist
);
5950 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
5951 Set displaced stepping debugging."), _("\
5952 Show displaced stepping debugging."), _("\
5953 When non-zero, displaced stepping specific debugging is enabled."),
5955 show_debug_displaced
,
5956 &setdebuglist
, &showdebuglist
);
5958 add_setshow_boolean_cmd ("non-stop", no_class
,
5960 Set whether gdb controls the inferior in non-stop mode."), _("\
5961 Show whether gdb controls the inferior in non-stop mode."), _("\
5962 When debugging a multi-threaded program and this setting is\n\
5963 off (the default, also called all-stop mode), when one thread stops\n\
5964 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
5965 all other threads in the program while you interact with the thread of\n\
5966 interest. When you continue or step a thread, you can allow the other\n\
5967 threads to run, or have them remain stopped, but while you inspect any\n\
5968 thread's state, all threads stop.\n\
5970 In non-stop mode, when one thread stops, other threads can continue\n\
5971 to run freely. You'll be able to step each thread independently,\n\
5972 leave it stopped or free to run as needed."),
5978 numsigs
= (int) TARGET_SIGNAL_LAST
;
5979 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
5980 signal_print
= (unsigned char *)
5981 xmalloc (sizeof (signal_print
[0]) * numsigs
);
5982 signal_program
= (unsigned char *)
5983 xmalloc (sizeof (signal_program
[0]) * numsigs
);
5984 for (i
= 0; i
< numsigs
; i
++)
5987 signal_print
[i
] = 1;
5988 signal_program
[i
] = 1;
5991 /* Signals caused by debugger's own actions
5992 should not be given to the program afterwards. */
5993 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
5994 signal_program
[TARGET_SIGNAL_INT
] = 0;
5996 /* Signals that are not errors should not normally enter the debugger. */
5997 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
5998 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
5999 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
6000 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
6001 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
6002 signal_print
[TARGET_SIGNAL_PROF
] = 0;
6003 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
6004 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
6005 signal_stop
[TARGET_SIGNAL_IO
] = 0;
6006 signal_print
[TARGET_SIGNAL_IO
] = 0;
6007 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
6008 signal_print
[TARGET_SIGNAL_POLL
] = 0;
6009 signal_stop
[TARGET_SIGNAL_URG
] = 0;
6010 signal_print
[TARGET_SIGNAL_URG
] = 0;
6011 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
6012 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
6014 /* These signals are used internally by user-level thread
6015 implementations. (See signal(5) on Solaris.) Like the above
6016 signals, a healthy program receives and handles them as part of
6017 its normal operation. */
6018 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
6019 signal_print
[TARGET_SIGNAL_LWP
] = 0;
6020 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
6021 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
6022 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
6023 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
6025 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
6026 &stop_on_solib_events
, _("\
6027 Set stopping for shared library events."), _("\
6028 Show stopping for shared library events."), _("\
6029 If nonzero, gdb will give control to the user when the dynamic linker\n\
6030 notifies gdb of shared library events. The most common event of interest\n\
6031 to the user would be loading/unloading of a new library."),
6033 show_stop_on_solib_events
,
6034 &setlist
, &showlist
);
6036 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
6037 follow_fork_mode_kind_names
,
6038 &follow_fork_mode_string
, _("\
6039 Set debugger response to a program call of fork or vfork."), _("\
6040 Show debugger response to a program call of fork or vfork."), _("\
6041 A fork or vfork creates a new process. follow-fork-mode can be:\n\
6042 parent - the original process is debugged after a fork\n\
6043 child - the new process is debugged after a fork\n\
6044 The unfollowed process will continue to run.\n\
6045 By default, the debugger will follow the parent process."),
6047 show_follow_fork_mode_string
,
6048 &setlist
, &showlist
);
6050 add_setshow_enum_cmd ("scheduler-locking", class_run
,
6051 scheduler_enums
, &scheduler_mode
, _("\
6052 Set mode for locking scheduler during execution."), _("\
6053 Show mode for locking scheduler during execution."), _("\
6054 off == no locking (threads may preempt at any time)\n\
6055 on == full locking (no thread except the current thread may run)\n\
6056 step == scheduler locked during every single-step operation.\n\
6057 In this mode, no other thread may run during a step command.\n\
6058 Other threads may run while stepping over a function call ('next')."),
6059 set_schedlock_func
, /* traps on target vector */
6060 show_scheduler_mode
,
6061 &setlist
, &showlist
);
6063 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
6064 Set mode for resuming threads of all processes."), _("\
6065 Show mode for resuming threads of all processes."), _("\
6066 When on, execution commands (such as 'continue' or 'next') resume all\n\
6067 threads of all processes. When off (which is the default), execution\n\
6068 commands only resume the threads of the current process. The set of\n\
6069 threads that are resumed is further refined by the scheduler-locking\n\
6070 mode (see help set scheduler-locking)."),
6072 show_schedule_multiple
,
6073 &setlist
, &showlist
);
6075 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
6076 Set mode of the step operation."), _("\
6077 Show mode of the step operation."), _("\
6078 When set, doing a step over a function without debug line information\n\
6079 will stop at the first instruction of that function. Otherwise, the\n\
6080 function is skipped and the step command stops at a different source line."),
6082 show_step_stop_if_no_debug
,
6083 &setlist
, &showlist
);
6085 add_setshow_enum_cmd ("displaced-stepping", class_run
,
6086 can_use_displaced_stepping_enum
,
6087 &can_use_displaced_stepping
, _("\
6088 Set debugger's willingness to use displaced stepping."), _("\
6089 Show debugger's willingness to use displaced stepping."), _("\
6090 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
6091 supported by the target architecture. If off, gdb will not use displaced\n\
6092 stepping to step over breakpoints, even if such is supported by the target\n\
6093 architecture. If auto (which is the default), gdb will use displaced stepping\n\
6094 if the target architecture supports it and non-stop mode is active, but will not\n\
6095 use it in all-stop mode (see help set non-stop)."),
6097 show_can_use_displaced_stepping
,
6098 &setlist
, &showlist
);
6100 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
6101 &exec_direction
, _("Set direction of execution.\n\
6102 Options are 'forward' or 'reverse'."),
6103 _("Show direction of execution (forward/reverse)."),
6104 _("Tells gdb whether to execute forward or backward."),
6105 set_exec_direction_func
, show_exec_direction_func
,
6106 &setlist
, &showlist
);
6108 /* ptid initializations */
6109 null_ptid
= ptid_build (0, 0, 0);
6110 minus_one_ptid
= ptid_build (-1, 0, 0);
6111 inferior_ptid
= null_ptid
;
6112 target_last_wait_ptid
= minus_one_ptid
;
6113 displaced_step_ptid
= null_ptid
;
6115 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
6116 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
6117 observer_attach_thread_exit (infrun_thread_thread_exit
);
6119 /* Explicitly create without lookup, since that tries to create a
6120 value with a void typed value, and when we get here, gdbarch
6121 isn't initialized yet. At this point, we're quite sure there
6122 isn't another convenience variable of the same name. */
6123 create_internalvar_type_lazy ("_siginfo", siginfo_make_value
);