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_displaced_step_hw_singlestep
1006 (gdbarch
, displaced_step_closure
))
1007 target_resume (ptid
, 1, TARGET_SIGNAL_0
);
1009 target_resume (ptid
, 0, TARGET_SIGNAL_0
);
1011 /* Done, we're stepping a thread. */
1017 struct thread_info
*tp
= inferior_thread ();
1019 /* The breakpoint we were sitting under has since been
1021 tp
->trap_expected
= 0;
1023 /* Go back to what we were trying to do. */
1024 step
= currently_stepping (tp
);
1026 if (debug_displaced
)
1027 fprintf_unfiltered (gdb_stdlog
, "breakpoint is gone %s: step(%d)\n",
1028 target_pid_to_str (tp
->ptid
), step
);
1030 target_resume (ptid
, step
, TARGET_SIGNAL_0
);
1031 tp
->stop_signal
= TARGET_SIGNAL_0
;
1033 /* This request was discarded. See if there's any other
1034 thread waiting for its turn. */
1039 /* Update global variables holding ptids to hold NEW_PTID if they were
1040 holding OLD_PTID. */
1042 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1044 struct displaced_step_request
*it
;
1046 if (ptid_equal (inferior_ptid
, old_ptid
))
1047 inferior_ptid
= new_ptid
;
1049 if (ptid_equal (singlestep_ptid
, old_ptid
))
1050 singlestep_ptid
= new_ptid
;
1052 if (ptid_equal (displaced_step_ptid
, old_ptid
))
1053 displaced_step_ptid
= new_ptid
;
1055 if (ptid_equal (deferred_step_ptid
, old_ptid
))
1056 deferred_step_ptid
= new_ptid
;
1058 for (it
= displaced_step_request_queue
; it
; it
= it
->next
)
1059 if (ptid_equal (it
->ptid
, old_ptid
))
1060 it
->ptid
= new_ptid
;
1066 /* Things to clean up if we QUIT out of resume (). */
1068 resume_cleanups (void *ignore
)
1073 static const char schedlock_off
[] = "off";
1074 static const char schedlock_on
[] = "on";
1075 static const char schedlock_step
[] = "step";
1076 static const char *scheduler_enums
[] = {
1082 static const char *scheduler_mode
= schedlock_off
;
1084 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1085 struct cmd_list_element
*c
, const char *value
)
1087 fprintf_filtered (file
, _("\
1088 Mode for locking scheduler during execution is \"%s\".\n"),
1093 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1095 if (!target_can_lock_scheduler
)
1097 scheduler_mode
= schedlock_off
;
1098 error (_("Target '%s' cannot support this command."), target_shortname
);
1102 /* True if execution commands resume all threads of all processes by
1103 default; otherwise, resume only threads of the current inferior
1105 int sched_multi
= 0;
1107 /* Try to setup for software single stepping over the specified location.
1108 Return 1 if target_resume() should use hardware single step.
1110 GDBARCH the current gdbarch.
1111 PC the location to step over. */
1114 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1118 if (gdbarch_software_single_step_p (gdbarch
)
1119 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1122 /* Do not pull these breakpoints until after a `wait' in
1123 `wait_for_inferior' */
1124 singlestep_breakpoints_inserted_p
= 1;
1125 singlestep_ptid
= inferior_ptid
;
1131 /* Resume the inferior, but allow a QUIT. This is useful if the user
1132 wants to interrupt some lengthy single-stepping operation
1133 (for child processes, the SIGINT goes to the inferior, and so
1134 we get a SIGINT random_signal, but for remote debugging and perhaps
1135 other targets, that's not true).
1137 STEP nonzero if we should step (zero to continue instead).
1138 SIG is the signal to give the inferior (zero for none). */
1140 resume (int step
, enum target_signal sig
)
1142 int should_resume
= 1;
1143 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
1144 struct regcache
*regcache
= get_current_regcache ();
1145 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1146 struct thread_info
*tp
= inferior_thread ();
1147 CORE_ADDR pc
= regcache_read_pc (regcache
);
1152 fprintf_unfiltered (gdb_stdlog
,
1153 "infrun: resume (step=%d, signal=%d), "
1154 "trap_expected=%d\n",
1155 step
, sig
, tp
->trap_expected
);
1157 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
1158 over an instruction that causes a page fault without triggering
1159 a hardware watchpoint. The kernel properly notices that it shouldn't
1160 stop, because the hardware watchpoint is not triggered, but it forgets
1161 the step request and continues the program normally.
1162 Work around the problem by removing hardware watchpoints if a step is
1163 requested, GDB will check for a hardware watchpoint trigger after the
1165 if (CANNOT_STEP_HW_WATCHPOINTS
&& step
)
1166 remove_hw_watchpoints ();
1169 /* Normally, by the time we reach `resume', the breakpoints are either
1170 removed or inserted, as appropriate. The exception is if we're sitting
1171 at a permanent breakpoint; we need to step over it, but permanent
1172 breakpoints can't be removed. So we have to test for it here. */
1173 if (breakpoint_here_p (pc
) == permanent_breakpoint_here
)
1175 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
1176 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
1179 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1180 how to step past a permanent breakpoint on this architecture. Try using\n\
1181 a command like `return' or `jump' to continue execution."));
1184 /* If enabled, step over breakpoints by executing a copy of the
1185 instruction at a different address.
1187 We can't use displaced stepping when we have a signal to deliver;
1188 the comments for displaced_step_prepare explain why. The
1189 comments in the handle_inferior event for dealing with 'random
1190 signals' explain what we do instead. */
1191 if (use_displaced_stepping (gdbarch
)
1192 && (tp
->trap_expected
1193 || (step
&& gdbarch_software_single_step_p (gdbarch
)))
1194 && sig
== TARGET_SIGNAL_0
)
1196 if (!displaced_step_prepare (inferior_ptid
))
1198 /* Got placed in displaced stepping queue. Will be resumed
1199 later when all the currently queued displaced stepping
1200 requests finish. The thread is not executing at this point,
1201 and the call to set_executing will be made later. But we
1202 need to call set_running here, since from frontend point of view,
1203 the thread is running. */
1204 set_running (inferior_ptid
, 1);
1205 discard_cleanups (old_cleanups
);
1209 step
= gdbarch_displaced_step_hw_singlestep
1210 (gdbarch
, displaced_step_closure
);
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
2391 handle_syscall_event (struct execution_control_state
*ecs
)
2393 struct regcache
*regcache
;
2394 struct gdbarch
*gdbarch
;
2397 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2398 context_switch (ecs
->ptid
);
2400 regcache
= get_thread_regcache (ecs
->ptid
);
2401 gdbarch
= get_regcache_arch (regcache
);
2402 syscall_number
= gdbarch_get_syscall_number (gdbarch
, ecs
->ptid
);
2403 stop_pc
= regcache_read_pc (regcache
);
2405 target_last_waitstatus
.value
.syscall_number
= syscall_number
;
2407 if (catch_syscall_enabled () > 0
2408 && catching_syscall_number (syscall_number
) > 0)
2411 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
2414 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2415 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2417 if (!ecs
->random_signal
)
2419 /* Catchpoint hit. */
2420 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2425 /* If no catchpoint triggered for this, then keep going. */
2426 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2431 /* Given an execution control state that has been freshly filled in
2432 by an event from the inferior, figure out what it means and take
2433 appropriate action. */
2436 handle_inferior_event (struct execution_control_state
*ecs
)
2438 struct frame_info
*frame
;
2439 struct gdbarch
*gdbarch
;
2440 int sw_single_step_trap_p
= 0;
2441 int stopped_by_watchpoint
;
2442 int stepped_after_stopped_by_watchpoint
= 0;
2443 struct symtab_and_line stop_pc_sal
;
2444 enum stop_kind stop_soon
;
2446 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2447 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2448 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
2450 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2452 stop_soon
= inf
->stop_soon
;
2455 stop_soon
= NO_STOP_QUIETLY
;
2457 /* Cache the last pid/waitstatus. */
2458 target_last_wait_ptid
= ecs
->ptid
;
2459 target_last_waitstatus
= ecs
->ws
;
2461 /* Always clear state belonging to the previous time we stopped. */
2462 stop_stack_dummy
= 0;
2464 /* If it's a new process, add it to the thread database */
2466 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
2467 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
2468 && !in_thread_list (ecs
->ptid
));
2470 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2471 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
2472 add_thread (ecs
->ptid
);
2474 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
2476 /* Dependent on valid ECS->EVENT_THREAD. */
2477 adjust_pc_after_break (ecs
);
2479 /* Dependent on the current PC value modified by adjust_pc_after_break. */
2480 reinit_frame_cache ();
2482 if (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
2484 breakpoint_retire_moribund ();
2486 /* Mark the non-executing threads accordingly. In all-stop, all
2487 threads of all processes are stopped when we get any event
2488 reported. In non-stop mode, only the event thread stops. If
2489 we're handling a process exit in non-stop mode, there's
2490 nothing to do, as threads of the dead process are gone, and
2491 threads of any other process were left running. */
2493 set_executing (minus_one_ptid
, 0);
2494 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2495 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
2496 set_executing (inferior_ptid
, 0);
2499 switch (infwait_state
)
2501 case infwait_thread_hop_state
:
2503 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
2506 case infwait_normal_state
:
2508 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
2511 case infwait_step_watch_state
:
2513 fprintf_unfiltered (gdb_stdlog
,
2514 "infrun: infwait_step_watch_state\n");
2516 stepped_after_stopped_by_watchpoint
= 1;
2519 case infwait_nonstep_watch_state
:
2521 fprintf_unfiltered (gdb_stdlog
,
2522 "infrun: infwait_nonstep_watch_state\n");
2523 insert_breakpoints ();
2525 /* FIXME-maybe: is this cleaner than setting a flag? Does it
2526 handle things like signals arriving and other things happening
2527 in combination correctly? */
2528 stepped_after_stopped_by_watchpoint
= 1;
2532 internal_error (__FILE__
, __LINE__
, _("bad switch"));
2535 infwait_state
= infwait_normal_state
;
2536 waiton_ptid
= pid_to_ptid (-1);
2538 switch (ecs
->ws
.kind
)
2540 case TARGET_WAITKIND_LOADED
:
2542 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
2543 /* Ignore gracefully during startup of the inferior, as it might
2544 be the shell which has just loaded some objects, otherwise
2545 add the symbols for the newly loaded objects. Also ignore at
2546 the beginning of an attach or remote session; we will query
2547 the full list of libraries once the connection is
2549 if (stop_soon
== NO_STOP_QUIETLY
)
2551 /* Check for any newly added shared libraries if we're
2552 supposed to be adding them automatically. Switch
2553 terminal for any messages produced by
2554 breakpoint_re_set. */
2555 target_terminal_ours_for_output ();
2556 /* NOTE: cagney/2003-11-25: Make certain that the target
2557 stack's section table is kept up-to-date. Architectures,
2558 (e.g., PPC64), use the section table to perform
2559 operations such as address => section name and hence
2560 require the table to contain all sections (including
2561 those found in shared libraries). */
2563 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2565 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2567 target_terminal_inferior ();
2569 /* If requested, stop when the dynamic linker notifies
2570 gdb of events. This allows the user to get control
2571 and place breakpoints in initializer routines for
2572 dynamically loaded objects (among other things). */
2573 if (stop_on_solib_events
)
2575 stop_stepping (ecs
);
2579 /* NOTE drow/2007-05-11: This might be a good place to check
2580 for "catch load". */
2583 /* If we are skipping through a shell, or through shared library
2584 loading that we aren't interested in, resume the program. If
2585 we're running the program normally, also resume. But stop if
2586 we're attaching or setting up a remote connection. */
2587 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
2589 /* Loading of shared libraries might have changed breakpoint
2590 addresses. Make sure new breakpoints are inserted. */
2591 if (stop_soon
== NO_STOP_QUIETLY
2592 && !breakpoints_always_inserted_mode ())
2593 insert_breakpoints ();
2594 resume (0, TARGET_SIGNAL_0
);
2595 prepare_to_wait (ecs
);
2601 case TARGET_WAITKIND_SPURIOUS
:
2603 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
2604 resume (0, TARGET_SIGNAL_0
);
2605 prepare_to_wait (ecs
);
2608 case TARGET_WAITKIND_EXITED
:
2610 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
2611 inferior_ptid
= ecs
->ptid
;
2612 target_terminal_ours (); /* Must do this before mourn anyway */
2613 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
2615 /* Record the exit code in the convenience variable $_exitcode, so
2616 that the user can inspect this again later. */
2617 set_internalvar_integer (lookup_internalvar ("_exitcode"),
2618 (LONGEST
) ecs
->ws
.value
.integer
);
2619 gdb_flush (gdb_stdout
);
2620 target_mourn_inferior ();
2621 singlestep_breakpoints_inserted_p
= 0;
2622 stop_print_frame
= 0;
2623 stop_stepping (ecs
);
2626 case TARGET_WAITKIND_SIGNALLED
:
2628 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2629 inferior_ptid
= ecs
->ptid
;
2630 stop_print_frame
= 0;
2631 target_terminal_ours (); /* Must do this before mourn anyway */
2633 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2634 reach here unless the inferior is dead. However, for years
2635 target_kill() was called here, which hints that fatal signals aren't
2636 really fatal on some systems. If that's true, then some changes
2638 target_mourn_inferior ();
2640 print_stop_reason (SIGNAL_EXITED
, ecs
->ws
.value
.sig
);
2641 singlestep_breakpoints_inserted_p
= 0;
2642 stop_stepping (ecs
);
2645 /* The following are the only cases in which we keep going;
2646 the above cases end in a continue or goto. */
2647 case TARGET_WAITKIND_FORKED
:
2648 case TARGET_WAITKIND_VFORKED
:
2650 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2652 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2654 context_switch (ecs
->ptid
);
2655 reinit_frame_cache ();
2658 /* Immediately detach breakpoints from the child before there's
2659 any chance of letting the user delete breakpoints from the
2660 breakpoint lists. If we don't do this early, it's easy to
2661 leave left over traps in the child, vis: "break foo; catch
2662 fork; c; <fork>; del; c; <child calls foo>". We only follow
2663 the fork on the last `continue', and by that time the
2664 breakpoint at "foo" is long gone from the breakpoint table.
2665 If we vforked, then we don't need to unpatch here, since both
2666 parent and child are sharing the same memory pages; we'll
2667 need to unpatch at follow/detach time instead to be certain
2668 that new breakpoints added between catchpoint hit time and
2669 vfork follow are detached. */
2670 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
2672 int child_pid
= ptid_get_pid (ecs
->ws
.value
.related_pid
);
2674 /* This won't actually modify the breakpoint list, but will
2675 physically remove the breakpoints from the child. */
2676 detach_breakpoints (child_pid
);
2679 /* In case the event is caught by a catchpoint, remember that
2680 the event is to be followed at the next resume of the thread,
2681 and not immediately. */
2682 ecs
->event_thread
->pending_follow
= ecs
->ws
;
2684 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2686 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2688 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2690 /* If no catchpoint triggered for this, then keep going. */
2691 if (ecs
->random_signal
)
2695 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2697 should_resume
= follow_fork ();
2699 ecs
->event_thread
= inferior_thread ();
2700 ecs
->ptid
= inferior_ptid
;
2705 stop_stepping (ecs
);
2708 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2709 goto process_event_stop_test
;
2711 case TARGET_WAITKIND_EXECD
:
2713 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
2715 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2717 context_switch (ecs
->ptid
);
2718 reinit_frame_cache ();
2721 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2723 /* This causes the eventpoints and symbol table to be reset.
2724 Must do this now, before trying to determine whether to
2726 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
2728 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2729 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2731 /* Note that this may be referenced from inside
2732 bpstat_stop_status above, through inferior_has_execd. */
2733 xfree (ecs
->ws
.value
.execd_pathname
);
2734 ecs
->ws
.value
.execd_pathname
= NULL
;
2736 /* If no catchpoint triggered for this, then keep going. */
2737 if (ecs
->random_signal
)
2739 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2743 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2744 goto process_event_stop_test
;
2746 /* Be careful not to try to gather much state about a thread
2747 that's in a syscall. It's frequently a losing proposition. */
2748 case TARGET_WAITKIND_SYSCALL_ENTRY
:
2750 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2751 /* Getting the current syscall number */
2752 if (handle_syscall_event (ecs
) != 0)
2754 goto process_event_stop_test
;
2756 /* Before examining the threads further, step this thread to
2757 get it entirely out of the syscall. (We get notice of the
2758 event when the thread is just on the verge of exiting a
2759 syscall. Stepping one instruction seems to get it back
2761 case TARGET_WAITKIND_SYSCALL_RETURN
:
2763 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2764 if (handle_syscall_event (ecs
) != 0)
2766 goto process_event_stop_test
;
2768 case TARGET_WAITKIND_STOPPED
:
2770 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
2771 ecs
->event_thread
->stop_signal
= ecs
->ws
.value
.sig
;
2774 case TARGET_WAITKIND_NO_HISTORY
:
2775 /* Reverse execution: target ran out of history info. */
2776 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2777 print_stop_reason (NO_HISTORY
, 0);
2778 stop_stepping (ecs
);
2781 /* We had an event in the inferior, but we are not interested
2782 in handling it at this level. The lower layers have already
2783 done what needs to be done, if anything.
2785 One of the possible circumstances for this is when the
2786 inferior produces output for the console. The inferior has
2787 not stopped, and we are ignoring the event. Another possible
2788 circumstance is any event which the lower level knows will be
2789 reported multiple times without an intervening resume. */
2790 case TARGET_WAITKIND_IGNORE
:
2792 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2793 prepare_to_wait (ecs
);
2797 if (ecs
->new_thread_event
)
2800 /* Non-stop assumes that the target handles adding new threads
2801 to the thread list. */
2802 internal_error (__FILE__
, __LINE__
, "\
2803 targets should add new threads to the thread list themselves in non-stop mode.");
2805 /* We may want to consider not doing a resume here in order to
2806 give the user a chance to play with the new thread. It might
2807 be good to make that a user-settable option. */
2809 /* At this point, all threads are stopped (happens automatically
2810 in either the OS or the native code). Therefore we need to
2811 continue all threads in order to make progress. */
2813 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2814 context_switch (ecs
->ptid
);
2815 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
2816 prepare_to_wait (ecs
);
2820 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
2822 /* Do we need to clean up the state of a thread that has
2823 completed a displaced single-step? (Doing so usually affects
2824 the PC, so do it here, before we set stop_pc.) */
2825 displaced_step_fixup (ecs
->ptid
, ecs
->event_thread
->stop_signal
);
2827 /* If we either finished a single-step or hit a breakpoint, but
2828 the user wanted this thread to be stopped, pretend we got a
2829 SIG0 (generic unsignaled stop). */
2831 if (ecs
->event_thread
->stop_requested
2832 && ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2833 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2836 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2840 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
2841 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
2843 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
2844 paddress (gdbarch
, stop_pc
));
2845 if (target_stopped_by_watchpoint ())
2848 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
2850 if (target_stopped_data_address (¤t_target
, &addr
))
2851 fprintf_unfiltered (gdb_stdlog
,
2852 "infrun: stopped data address = %s\n",
2853 paddress (gdbarch
, addr
));
2855 fprintf_unfiltered (gdb_stdlog
,
2856 "infrun: (no data address available)\n");
2860 if (stepping_past_singlestep_breakpoint
)
2862 gdb_assert (singlestep_breakpoints_inserted_p
);
2863 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
2864 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
2866 stepping_past_singlestep_breakpoint
= 0;
2868 /* We've either finished single-stepping past the single-step
2869 breakpoint, or stopped for some other reason. It would be nice if
2870 we could tell, but we can't reliably. */
2871 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2874 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
2875 /* Pull the single step breakpoints out of the target. */
2876 remove_single_step_breakpoints ();
2877 singlestep_breakpoints_inserted_p
= 0;
2879 ecs
->random_signal
= 0;
2880 ecs
->event_thread
->trap_expected
= 0;
2882 context_switch (saved_singlestep_ptid
);
2883 if (deprecated_context_hook
)
2884 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2886 resume (1, TARGET_SIGNAL_0
);
2887 prepare_to_wait (ecs
);
2892 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
2894 /* In non-stop mode, there's never a deferred_step_ptid set. */
2895 gdb_assert (!non_stop
);
2897 /* If we stopped for some other reason than single-stepping, ignore
2898 the fact that we were supposed to switch back. */
2899 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2902 fprintf_unfiltered (gdb_stdlog
,
2903 "infrun: handling deferred step\n");
2905 /* Pull the single step breakpoints out of the target. */
2906 if (singlestep_breakpoints_inserted_p
)
2908 remove_single_step_breakpoints ();
2909 singlestep_breakpoints_inserted_p
= 0;
2912 /* Note: We do not call context_switch at this point, as the
2913 context is already set up for stepping the original thread. */
2914 switch_to_thread (deferred_step_ptid
);
2915 deferred_step_ptid
= null_ptid
;
2916 /* Suppress spurious "Switching to ..." message. */
2917 previous_inferior_ptid
= inferior_ptid
;
2919 resume (1, TARGET_SIGNAL_0
);
2920 prepare_to_wait (ecs
);
2924 deferred_step_ptid
= null_ptid
;
2927 /* See if a thread hit a thread-specific breakpoint that was meant for
2928 another thread. If so, then step that thread past the breakpoint,
2931 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2933 int thread_hop_needed
= 0;
2935 /* Check if a regular breakpoint has been hit before checking
2936 for a potential single step breakpoint. Otherwise, GDB will
2937 not see this breakpoint hit when stepping onto breakpoints. */
2938 if (regular_breakpoint_inserted_here_p (stop_pc
))
2940 ecs
->random_signal
= 0;
2941 if (!breakpoint_thread_match (stop_pc
, ecs
->ptid
))
2942 thread_hop_needed
= 1;
2944 else if (singlestep_breakpoints_inserted_p
)
2946 /* We have not context switched yet, so this should be true
2947 no matter which thread hit the singlestep breakpoint. */
2948 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
2950 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
2952 target_pid_to_str (ecs
->ptid
));
2954 ecs
->random_signal
= 0;
2955 /* The call to in_thread_list is necessary because PTIDs sometimes
2956 change when we go from single-threaded to multi-threaded. If
2957 the singlestep_ptid is still in the list, assume that it is
2958 really different from ecs->ptid. */
2959 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
2960 && in_thread_list (singlestep_ptid
))
2962 /* If the PC of the thread we were trying to single-step
2963 has changed, discard this event (which we were going
2964 to ignore anyway), and pretend we saw that thread
2965 trap. This prevents us continuously moving the
2966 single-step breakpoint forward, one instruction at a
2967 time. If the PC has changed, then the thread we were
2968 trying to single-step has trapped or been signalled,
2969 but the event has not been reported to GDB yet.
2971 There might be some cases where this loses signal
2972 information, if a signal has arrived at exactly the
2973 same time that the PC changed, but this is the best
2974 we can do with the information available. Perhaps we
2975 should arrange to report all events for all threads
2976 when they stop, or to re-poll the remote looking for
2977 this particular thread (i.e. temporarily enable
2980 CORE_ADDR new_singlestep_pc
2981 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
2983 if (new_singlestep_pc
!= singlestep_pc
)
2985 enum target_signal stop_signal
;
2988 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
2989 " but expected thread advanced also\n");
2991 /* The current context still belongs to
2992 singlestep_ptid. Don't swap here, since that's
2993 the context we want to use. Just fudge our
2994 state and continue. */
2995 stop_signal
= ecs
->event_thread
->stop_signal
;
2996 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2997 ecs
->ptid
= singlestep_ptid
;
2998 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
2999 ecs
->event_thread
->stop_signal
= stop_signal
;
3000 stop_pc
= new_singlestep_pc
;
3005 fprintf_unfiltered (gdb_stdlog
,
3006 "infrun: unexpected thread\n");
3008 thread_hop_needed
= 1;
3009 stepping_past_singlestep_breakpoint
= 1;
3010 saved_singlestep_ptid
= singlestep_ptid
;
3015 if (thread_hop_needed
)
3017 struct regcache
*thread_regcache
;
3018 int remove_status
= 0;
3021 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3023 /* Switch context before touching inferior memory, the
3024 previous thread may have exited. */
3025 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3026 context_switch (ecs
->ptid
);
3028 /* Saw a breakpoint, but it was hit by the wrong thread.
3031 if (singlestep_breakpoints_inserted_p
)
3033 /* Pull the single step breakpoints out of the target. */
3034 remove_single_step_breakpoints ();
3035 singlestep_breakpoints_inserted_p
= 0;
3038 /* If the arch can displace step, don't remove the
3040 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3041 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3042 remove_status
= remove_breakpoints ();
3044 /* Did we fail to remove breakpoints? If so, try
3045 to set the PC past the bp. (There's at least
3046 one situation in which we can fail to remove
3047 the bp's: On HP-UX's that use ttrace, we can't
3048 change the address space of a vforking child
3049 process until the child exits (well, okay, not
3050 then either :-) or execs. */
3051 if (remove_status
!= 0)
3052 error (_("Cannot step over breakpoint hit in wrong thread"));
3057 /* Only need to require the next event from this
3058 thread in all-stop mode. */
3059 waiton_ptid
= ecs
->ptid
;
3060 infwait_state
= infwait_thread_hop_state
;
3063 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3068 else if (singlestep_breakpoints_inserted_p
)
3070 sw_single_step_trap_p
= 1;
3071 ecs
->random_signal
= 0;
3075 ecs
->random_signal
= 1;
3077 /* See if something interesting happened to the non-current thread. If
3078 so, then switch to that thread. */
3079 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3082 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3084 context_switch (ecs
->ptid
);
3086 if (deprecated_context_hook
)
3087 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3090 /* At this point, get hold of the now-current thread's frame. */
3091 frame
= get_current_frame ();
3092 gdbarch
= get_frame_arch (frame
);
3094 if (singlestep_breakpoints_inserted_p
)
3096 /* Pull the single step breakpoints out of the target. */
3097 remove_single_step_breakpoints ();
3098 singlestep_breakpoints_inserted_p
= 0;
3101 if (stepped_after_stopped_by_watchpoint
)
3102 stopped_by_watchpoint
= 0;
3104 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
3106 /* If necessary, step over this watchpoint. We'll be back to display
3108 if (stopped_by_watchpoint
3109 && (target_have_steppable_watchpoint
3110 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
3112 /* At this point, we are stopped at an instruction which has
3113 attempted to write to a piece of memory under control of
3114 a watchpoint. The instruction hasn't actually executed
3115 yet. If we were to evaluate the watchpoint expression
3116 now, we would get the old value, and therefore no change
3117 would seem to have occurred.
3119 In order to make watchpoints work `right', we really need
3120 to complete the memory write, and then evaluate the
3121 watchpoint expression. We do this by single-stepping the
3124 It may not be necessary to disable the watchpoint to stop over
3125 it. For example, the PA can (with some kernel cooperation)
3126 single step over a watchpoint without disabling the watchpoint.
3128 It is far more common to need to disable a watchpoint to step
3129 the inferior over it. If we have non-steppable watchpoints,
3130 we must disable the current watchpoint; it's simplest to
3131 disable all watchpoints and breakpoints. */
3134 if (!target_have_steppable_watchpoint
)
3135 remove_breakpoints ();
3137 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
3138 target_resume (ecs
->ptid
, hw_step
, TARGET_SIGNAL_0
);
3139 waiton_ptid
= ecs
->ptid
;
3140 if (target_have_steppable_watchpoint
)
3141 infwait_state
= infwait_step_watch_state
;
3143 infwait_state
= infwait_nonstep_watch_state
;
3144 prepare_to_wait (ecs
);
3148 ecs
->stop_func_start
= 0;
3149 ecs
->stop_func_end
= 0;
3150 ecs
->stop_func_name
= 0;
3151 /* Don't care about return value; stop_func_start and stop_func_name
3152 will both be 0 if it doesn't work. */
3153 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3154 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3155 ecs
->stop_func_start
3156 += gdbarch_deprecated_function_start_offset (gdbarch
);
3157 ecs
->event_thread
->stepping_over_breakpoint
= 0;
3158 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
3159 ecs
->event_thread
->stop_step
= 0;
3160 stop_print_frame
= 1;
3161 ecs
->random_signal
= 0;
3162 stopped_by_random_signal
= 0;
3164 /* Hide inlined functions starting here, unless we just performed stepi or
3165 nexti. After stepi and nexti, always show the innermost frame (not any
3166 inline function call sites). */
3167 if (ecs
->event_thread
->step_range_end
!= 1)
3168 skip_inline_frames (ecs
->ptid
);
3170 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3171 && ecs
->event_thread
->trap_expected
3172 && gdbarch_single_step_through_delay_p (gdbarch
)
3173 && currently_stepping (ecs
->event_thread
))
3175 /* We're trying to step off a breakpoint. Turns out that we're
3176 also on an instruction that needs to be stepped multiple
3177 times before it's been fully executing. E.g., architectures
3178 with a delay slot. It needs to be stepped twice, once for
3179 the instruction and once for the delay slot. */
3180 int step_through_delay
3181 = gdbarch_single_step_through_delay (gdbarch
, frame
);
3182 if (debug_infrun
&& step_through_delay
)
3183 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
3184 if (ecs
->event_thread
->step_range_end
== 0 && step_through_delay
)
3186 /* The user issued a continue when stopped at a breakpoint.
3187 Set up for another trap and get out of here. */
3188 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3192 else if (step_through_delay
)
3194 /* The user issued a step when stopped at a breakpoint.
3195 Maybe we should stop, maybe we should not - the delay
3196 slot *might* correspond to a line of source. In any
3197 case, don't decide that here, just set
3198 ecs->stepping_over_breakpoint, making sure we
3199 single-step again before breakpoints are re-inserted. */
3200 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3204 /* Look at the cause of the stop, and decide what to do.
3205 The alternatives are:
3206 1) stop_stepping and return; to really stop and return to the debugger,
3207 2) keep_going and return to start up again
3208 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
3209 3) set ecs->random_signal to 1, and the decision between 1 and 2
3210 will be made according to the signal handling tables. */
3212 /* First, distinguish signals caused by the debugger from signals
3213 that have to do with the program's own actions. Note that
3214 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3215 on the operating system version. Here we detect when a SIGILL or
3216 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3217 something similar for SIGSEGV, since a SIGSEGV will be generated
3218 when we're trying to execute a breakpoint instruction on a
3219 non-executable stack. This happens for call dummy breakpoints
3220 for architectures like SPARC that place call dummies on the
3223 If we're doing a displaced step past a breakpoint, then the
3224 breakpoint is always inserted at the original instruction;
3225 non-standard signals can't be explained by the breakpoint. */
3226 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3227 || (! ecs
->event_thread
->trap_expected
3228 && breakpoint_inserted_here_p (stop_pc
)
3229 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_ILL
3230 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_SEGV
3231 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_EMT
))
3232 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3233 || stop_soon
== STOP_QUIETLY_REMOTE
)
3235 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
3238 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
3239 stop_print_frame
= 0;
3240 stop_stepping (ecs
);
3244 /* This is originated from start_remote(), start_inferior() and
3245 shared libraries hook functions. */
3246 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
3249 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3250 stop_stepping (ecs
);
3254 /* This originates from attach_command(). We need to overwrite
3255 the stop_signal here, because some kernels don't ignore a
3256 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
3257 See more comments in inferior.h. On the other hand, if we
3258 get a non-SIGSTOP, report it to the user - assume the backend
3259 will handle the SIGSTOP if it should show up later.
3261 Also consider that the attach is complete when we see a
3262 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
3263 target extended-remote report it instead of a SIGSTOP
3264 (e.g. gdbserver). We already rely on SIGTRAP being our
3265 signal, so this is no exception.
3267 Also consider that the attach is complete when we see a
3268 TARGET_SIGNAL_0. In non-stop mode, GDB will explicitly tell
3269 the target to stop all threads of the inferior, in case the
3270 low level attach operation doesn't stop them implicitly. If
3271 they weren't stopped implicitly, then the stub will report a
3272 TARGET_SIGNAL_0, meaning: stopped for no particular reason
3273 other than GDB's request. */
3274 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3275 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_STOP
3276 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3277 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_0
))
3279 stop_stepping (ecs
);
3280 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3284 /* See if there is a breakpoint at the current PC. */
3285 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
3287 /* Following in case break condition called a
3289 stop_print_frame
= 1;
3291 /* NOTE: cagney/2003-03-29: These two checks for a random signal
3292 at one stage in the past included checks for an inferior
3293 function call's call dummy's return breakpoint. The original
3294 comment, that went with the test, read:
3296 ``End of a stack dummy. Some systems (e.g. Sony news) give
3297 another signal besides SIGTRAP, so check here as well as
3300 If someone ever tries to get call dummys on a
3301 non-executable stack to work (where the target would stop
3302 with something like a SIGSEGV), then those tests might need
3303 to be re-instated. Given, however, that the tests were only
3304 enabled when momentary breakpoints were not being used, I
3305 suspect that it won't be the case.
3307 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
3308 be necessary for call dummies on a non-executable stack on
3311 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
3313 = !(bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
)
3314 || ecs
->event_thread
->trap_expected
3315 || (ecs
->event_thread
->step_range_end
3316 && ecs
->event_thread
->step_resume_breakpoint
== NULL
));
3319 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
3320 if (!ecs
->random_signal
)
3321 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
3325 /* When we reach this point, we've pretty much decided
3326 that the reason for stopping must've been a random
3327 (unexpected) signal. */
3330 ecs
->random_signal
= 1;
3332 process_event_stop_test
:
3334 /* Re-fetch current thread's frame in case we did a
3335 "goto process_event_stop_test" above. */
3336 frame
= get_current_frame ();
3337 gdbarch
= get_frame_arch (frame
);
3339 /* For the program's own signals, act according to
3340 the signal handling tables. */
3342 if (ecs
->random_signal
)
3344 /* Signal not for debugging purposes. */
3348 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
3349 ecs
->event_thread
->stop_signal
);
3351 stopped_by_random_signal
= 1;
3353 if (signal_print
[ecs
->event_thread
->stop_signal
])
3356 target_terminal_ours_for_output ();
3357 print_stop_reason (SIGNAL_RECEIVED
, ecs
->event_thread
->stop_signal
);
3359 /* Always stop on signals if we're either just gaining control
3360 of the program, or the user explicitly requested this thread
3361 to remain stopped. */
3362 if (stop_soon
!= NO_STOP_QUIETLY
3363 || ecs
->event_thread
->stop_requested
3364 || signal_stop_state (ecs
->event_thread
->stop_signal
))
3366 stop_stepping (ecs
);
3369 /* If not going to stop, give terminal back
3370 if we took it away. */
3372 target_terminal_inferior ();
3374 /* Clear the signal if it should not be passed. */
3375 if (signal_program
[ecs
->event_thread
->stop_signal
] == 0)
3376 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3378 if (ecs
->event_thread
->prev_pc
== stop_pc
3379 && ecs
->event_thread
->trap_expected
3380 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
3382 /* We were just starting a new sequence, attempting to
3383 single-step off of a breakpoint and expecting a SIGTRAP.
3384 Instead this signal arrives. This signal will take us out
3385 of the stepping range so GDB needs to remember to, when
3386 the signal handler returns, resume stepping off that
3388 /* To simplify things, "continue" is forced to use the same
3389 code paths as single-step - set a breakpoint at the
3390 signal return address and then, once hit, step off that
3393 fprintf_unfiltered (gdb_stdlog
,
3394 "infrun: signal arrived while stepping over "
3397 insert_step_resume_breakpoint_at_frame (frame
);
3398 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
3403 if (ecs
->event_thread
->step_range_end
!= 0
3404 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_0
3405 && (ecs
->event_thread
->step_range_start
<= stop_pc
3406 && stop_pc
< ecs
->event_thread
->step_range_end
)
3407 && frame_id_eq (get_stack_frame_id (frame
),
3408 ecs
->event_thread
->step_stack_frame_id
)
3409 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
3411 /* The inferior is about to take a signal that will take it
3412 out of the single step range. Set a breakpoint at the
3413 current PC (which is presumably where the signal handler
3414 will eventually return) and then allow the inferior to
3417 Note that this is only needed for a signal delivered
3418 while in the single-step range. Nested signals aren't a
3419 problem as they eventually all return. */
3421 fprintf_unfiltered (gdb_stdlog
,
3422 "infrun: signal may take us out of "
3423 "single-step range\n");
3425 insert_step_resume_breakpoint_at_frame (frame
);
3430 /* Note: step_resume_breakpoint may be non-NULL. This occures
3431 when either there's a nested signal, or when there's a
3432 pending signal enabled just as the signal handler returns
3433 (leaving the inferior at the step-resume-breakpoint without
3434 actually executing it). Either way continue until the
3435 breakpoint is really hit. */
3440 /* Handle cases caused by hitting a breakpoint. */
3442 CORE_ADDR jmp_buf_pc
;
3443 struct bpstat_what what
;
3445 what
= bpstat_what (ecs
->event_thread
->stop_bpstat
);
3447 if (what
.call_dummy
)
3449 stop_stack_dummy
= 1;
3452 switch (what
.main_action
)
3454 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
3455 /* If we hit the breakpoint at longjmp while stepping, we
3456 install a momentary breakpoint at the target of the
3460 fprintf_unfiltered (gdb_stdlog
,
3461 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
3463 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3465 if (!gdbarch_get_longjmp_target_p (gdbarch
)
3466 || !gdbarch_get_longjmp_target (gdbarch
, frame
, &jmp_buf_pc
))
3469 fprintf_unfiltered (gdb_stdlog
, "\
3470 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
3475 /* We're going to replace the current step-resume breakpoint
3476 with a longjmp-resume breakpoint. */
3477 delete_step_resume_breakpoint (ecs
->event_thread
);
3479 /* Insert a breakpoint at resume address. */
3480 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
3485 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
3487 fprintf_unfiltered (gdb_stdlog
,
3488 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
3490 gdb_assert (ecs
->event_thread
->step_resume_breakpoint
!= NULL
);
3491 delete_step_resume_breakpoint (ecs
->event_thread
);
3493 ecs
->event_thread
->stop_step
= 1;
3494 print_stop_reason (END_STEPPING_RANGE
, 0);
3495 stop_stepping (ecs
);
3498 case BPSTAT_WHAT_SINGLE
:
3500 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
3501 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3502 /* Still need to check other stuff, at least the case
3503 where we are stepping and step out of the right range. */
3506 case BPSTAT_WHAT_STOP_NOISY
:
3508 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
3509 stop_print_frame
= 1;
3511 /* We are about to nuke the step_resume_breakpointt via the
3512 cleanup chain, so no need to worry about it here. */
3514 stop_stepping (ecs
);
3517 case BPSTAT_WHAT_STOP_SILENT
:
3519 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
3520 stop_print_frame
= 0;
3522 /* We are about to nuke the step_resume_breakpoin via the
3523 cleanup chain, so no need to worry about it here. */
3525 stop_stepping (ecs
);
3528 case BPSTAT_WHAT_STEP_RESUME
:
3530 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
3532 delete_step_resume_breakpoint (ecs
->event_thread
);
3533 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
3535 /* Back when the step-resume breakpoint was inserted, we
3536 were trying to single-step off a breakpoint. Go back
3538 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
3539 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3543 if (stop_pc
== ecs
->stop_func_start
3544 && execution_direction
== EXEC_REVERSE
)
3546 /* We are stepping over a function call in reverse, and
3547 just hit the step-resume breakpoint at the start
3548 address of the function. Go back to single-stepping,
3549 which should take us back to the function call. */
3550 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3556 case BPSTAT_WHAT_CHECK_SHLIBS
:
3559 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
3561 /* Check for any newly added shared libraries if we're
3562 supposed to be adding them automatically. Switch
3563 terminal for any messages produced by
3564 breakpoint_re_set. */
3565 target_terminal_ours_for_output ();
3566 /* NOTE: cagney/2003-11-25: Make certain that the target
3567 stack's section table is kept up-to-date. Architectures,
3568 (e.g., PPC64), use the section table to perform
3569 operations such as address => section name and hence
3570 require the table to contain all sections (including
3571 those found in shared libraries). */
3573 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
3575 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
3577 target_terminal_inferior ();
3579 /* If requested, stop when the dynamic linker notifies
3580 gdb of events. This allows the user to get control
3581 and place breakpoints in initializer routines for
3582 dynamically loaded objects (among other things). */
3583 if (stop_on_solib_events
|| stop_stack_dummy
)
3585 stop_stepping (ecs
);
3590 /* We want to step over this breakpoint, then keep going. */
3591 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3597 case BPSTAT_WHAT_CHECK_JIT
:
3599 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_JIT\n");
3601 /* Switch terminal for any messages produced by breakpoint_re_set. */
3602 target_terminal_ours_for_output ();
3604 jit_event_handler (gdbarch
);
3606 target_terminal_inferior ();
3608 /* We want to step over this breakpoint, then keep going. */
3609 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3613 case BPSTAT_WHAT_LAST
:
3614 /* Not a real code, but listed here to shut up gcc -Wall. */
3616 case BPSTAT_WHAT_KEEP_CHECKING
:
3621 /* We come here if we hit a breakpoint but should not
3622 stop for it. Possibly we also were stepping
3623 and should stop for that. So fall through and
3624 test for stepping. But, if not stepping,
3627 /* In all-stop mode, if we're currently stepping but have stopped in
3628 some other thread, we need to switch back to the stepped thread. */
3631 struct thread_info
*tp
;
3632 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
3636 /* However, if the current thread is blocked on some internal
3637 breakpoint, and we simply need to step over that breakpoint
3638 to get it going again, do that first. */
3639 if ((ecs
->event_thread
->trap_expected
3640 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
3641 || ecs
->event_thread
->stepping_over_breakpoint
)
3647 /* If the stepping thread exited, then don't try to switch
3648 back and resume it, which could fail in several different
3649 ways depending on the target. Instead, just keep going.
3651 We can find a stepping dead thread in the thread list in
3654 - The target supports thread exit events, and when the
3655 target tries to delete the thread from the thread list,
3656 inferior_ptid pointed at the exiting thread. In such
3657 case, calling delete_thread does not really remove the
3658 thread from the list; instead, the thread is left listed,
3659 with 'exited' state.
3661 - The target's debug interface does not support thread
3662 exit events, and so we have no idea whatsoever if the
3663 previously stepping thread is still alive. For that
3664 reason, we need to synchronously query the target
3666 if (is_exited (tp
->ptid
)
3667 || !target_thread_alive (tp
->ptid
))
3670 fprintf_unfiltered (gdb_stdlog
, "\
3671 infrun: not switching back to stepped thread, it has vanished\n");
3673 delete_thread (tp
->ptid
);
3678 /* Otherwise, we no longer expect a trap in the current thread.
3679 Clear the trap_expected flag before switching back -- this is
3680 what keep_going would do as well, if we called it. */
3681 ecs
->event_thread
->trap_expected
= 0;
3684 fprintf_unfiltered (gdb_stdlog
,
3685 "infrun: switching back to stepped thread\n");
3687 ecs
->event_thread
= tp
;
3688 ecs
->ptid
= tp
->ptid
;
3689 context_switch (ecs
->ptid
);
3695 /* Are we stepping to get the inferior out of the dynamic linker's
3696 hook (and possibly the dld itself) after catching a shlib
3698 if (ecs
->event_thread
->stepping_through_solib_after_catch
)
3700 #if defined(SOLIB_ADD)
3701 /* Have we reached our destination? If not, keep going. */
3702 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
3705 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
3706 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3712 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
3713 /* Else, stop and report the catchpoint(s) whose triggering
3714 caused us to begin stepping. */
3715 ecs
->event_thread
->stepping_through_solib_after_catch
= 0;
3716 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
3717 ecs
->event_thread
->stop_bpstat
3718 = bpstat_copy (ecs
->event_thread
->stepping_through_solib_catchpoints
);
3719 bpstat_clear (&ecs
->event_thread
->stepping_through_solib_catchpoints
);
3720 stop_print_frame
= 1;
3721 stop_stepping (ecs
);
3725 if (ecs
->event_thread
->step_resume_breakpoint
)
3728 fprintf_unfiltered (gdb_stdlog
,
3729 "infrun: step-resume breakpoint is inserted\n");
3731 /* Having a step-resume breakpoint overrides anything
3732 else having to do with stepping commands until
3733 that breakpoint is reached. */
3738 if (ecs
->event_thread
->step_range_end
== 0)
3741 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
3742 /* Likewise if we aren't even stepping. */
3747 /* If stepping through a line, keep going if still within it.
3749 Note that step_range_end is the address of the first instruction
3750 beyond the step range, and NOT the address of the last instruction
3753 Note also that during reverse execution, we may be stepping
3754 through a function epilogue and therefore must detect when
3755 the current-frame changes in the middle of a line. */
3757 if (stop_pc
>= ecs
->event_thread
->step_range_start
3758 && stop_pc
< ecs
->event_thread
->step_range_end
3759 && (execution_direction
!= EXEC_REVERSE
3760 || frame_id_eq (get_frame_id (frame
),
3761 ecs
->event_thread
->step_frame_id
)))
3765 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
3766 paddress (gdbarch
, ecs
->event_thread
->step_range_start
),
3767 paddress (gdbarch
, ecs
->event_thread
->step_range_end
));
3769 /* When stepping backward, stop at beginning of line range
3770 (unless it's the function entry point, in which case
3771 keep going back to the call point). */
3772 if (stop_pc
== ecs
->event_thread
->step_range_start
3773 && stop_pc
!= ecs
->stop_func_start
3774 && execution_direction
== EXEC_REVERSE
)
3776 ecs
->event_thread
->stop_step
= 1;
3777 print_stop_reason (END_STEPPING_RANGE
, 0);
3778 stop_stepping (ecs
);
3786 /* We stepped out of the stepping range. */
3788 /* If we are stepping at the source level and entered the runtime
3789 loader dynamic symbol resolution code...
3791 EXEC_FORWARD: we keep on single stepping until we exit the run
3792 time loader code and reach the callee's address.
3794 EXEC_REVERSE: we've already executed the callee (backward), and
3795 the runtime loader code is handled just like any other
3796 undebuggable function call. Now we need only keep stepping
3797 backward through the trampoline code, and that's handled further
3798 down, so there is nothing for us to do here. */
3800 if (execution_direction
!= EXEC_REVERSE
3801 && ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3802 && in_solib_dynsym_resolve_code (stop_pc
))
3804 CORE_ADDR pc_after_resolver
=
3805 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
3808 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
3810 if (pc_after_resolver
)
3812 /* Set up a step-resume breakpoint at the address
3813 indicated by SKIP_SOLIB_RESOLVER. */
3814 struct symtab_and_line sr_sal
;
3816 sr_sal
.pc
= pc_after_resolver
;
3818 insert_step_resume_breakpoint_at_sal (gdbarch
,
3819 sr_sal
, null_frame_id
);
3826 if (ecs
->event_thread
->step_range_end
!= 1
3827 && (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3828 || ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3829 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
3832 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
3833 /* The inferior, while doing a "step" or "next", has ended up in
3834 a signal trampoline (either by a signal being delivered or by
3835 the signal handler returning). Just single-step until the
3836 inferior leaves the trampoline (either by calling the handler
3842 /* Check for subroutine calls. The check for the current frame
3843 equalling the step ID is not necessary - the check of the
3844 previous frame's ID is sufficient - but it is a common case and
3845 cheaper than checking the previous frame's ID.
3847 NOTE: frame_id_eq will never report two invalid frame IDs as
3848 being equal, so to get into this block, both the current and
3849 previous frame must have valid frame IDs. */
3850 /* The outer_frame_id check is a heuristic to detect stepping
3851 through startup code. If we step over an instruction which
3852 sets the stack pointer from an invalid value to a valid value,
3853 we may detect that as a subroutine call from the mythical
3854 "outermost" function. This could be fixed by marking
3855 outermost frames as !stack_p,code_p,special_p. Then the
3856 initial outermost frame, before sp was valid, would
3857 have code_addr == &_start. See the commend in frame_id_eq
3859 if (!frame_id_eq (get_stack_frame_id (frame
),
3860 ecs
->event_thread
->step_stack_frame_id
)
3861 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
3862 ecs
->event_thread
->step_stack_frame_id
)
3863 && (!frame_id_eq (ecs
->event_thread
->step_stack_frame_id
,
3865 || step_start_function
!= find_pc_function (stop_pc
))))
3867 CORE_ADDR real_stop_pc
;
3870 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
3872 if ((ecs
->event_thread
->step_over_calls
== STEP_OVER_NONE
)
3873 || ((ecs
->event_thread
->step_range_end
== 1)
3874 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
3875 ecs
->stop_func_start
)))
3877 /* I presume that step_over_calls is only 0 when we're
3878 supposed to be stepping at the assembly language level
3879 ("stepi"). Just stop. */
3880 /* Also, maybe we just did a "nexti" inside a prolog, so we
3881 thought it was a subroutine call but it was not. Stop as
3883 /* And this works the same backward as frontward. MVS */
3884 ecs
->event_thread
->stop_step
= 1;
3885 print_stop_reason (END_STEPPING_RANGE
, 0);
3886 stop_stepping (ecs
);
3890 /* Reverse stepping through solib trampolines. */
3892 if (execution_direction
== EXEC_REVERSE
3893 && ecs
->event_thread
->step_over_calls
!= STEP_OVER_NONE
3894 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
3895 || (ecs
->stop_func_start
== 0
3896 && in_solib_dynsym_resolve_code (stop_pc
))))
3898 /* Any solib trampoline code can be handled in reverse
3899 by simply continuing to single-step. We have already
3900 executed the solib function (backwards), and a few
3901 steps will take us back through the trampoline to the
3907 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3909 /* We're doing a "next".
3911 Normal (forward) execution: set a breakpoint at the
3912 callee's return address (the address at which the caller
3915 Reverse (backward) execution. set the step-resume
3916 breakpoint at the start of the function that we just
3917 stepped into (backwards), and continue to there. When we
3918 get there, we'll need to single-step back to the caller. */
3920 if (execution_direction
== EXEC_REVERSE
)
3922 struct symtab_and_line sr_sal
;
3924 /* Normal function call return (static or dynamic). */
3926 sr_sal
.pc
= ecs
->stop_func_start
;
3927 insert_step_resume_breakpoint_at_sal (gdbarch
,
3928 sr_sal
, null_frame_id
);
3931 insert_step_resume_breakpoint_at_caller (frame
);
3937 /* If we are in a function call trampoline (a stub between the
3938 calling routine and the real function), locate the real
3939 function. That's what tells us (a) whether we want to step
3940 into it at all, and (b) what prologue we want to run to the
3941 end of, if we do step into it. */
3942 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
3943 if (real_stop_pc
== 0)
3944 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
3945 if (real_stop_pc
!= 0)
3946 ecs
->stop_func_start
= real_stop_pc
;
3948 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
3950 struct symtab_and_line sr_sal
;
3952 sr_sal
.pc
= ecs
->stop_func_start
;
3954 insert_step_resume_breakpoint_at_sal (gdbarch
,
3955 sr_sal
, null_frame_id
);
3960 /* If we have line number information for the function we are
3961 thinking of stepping into, step into it.
3963 If there are several symtabs at that PC (e.g. with include
3964 files), just want to know whether *any* of them have line
3965 numbers. find_pc_line handles this. */
3967 struct symtab_and_line tmp_sal
;
3969 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3970 if (tmp_sal
.line
!= 0)
3972 if (execution_direction
== EXEC_REVERSE
)
3973 handle_step_into_function_backward (gdbarch
, ecs
);
3975 handle_step_into_function (gdbarch
, ecs
);
3980 /* If we have no line number and the step-stop-if-no-debug is
3981 set, we stop the step so that the user has a chance to switch
3982 in assembly mode. */
3983 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3984 && step_stop_if_no_debug
)
3986 ecs
->event_thread
->stop_step
= 1;
3987 print_stop_reason (END_STEPPING_RANGE
, 0);
3988 stop_stepping (ecs
);
3992 if (execution_direction
== EXEC_REVERSE
)
3994 /* Set a breakpoint at callee's start address.
3995 From there we can step once and be back in the caller. */
3996 struct symtab_and_line sr_sal
;
3998 sr_sal
.pc
= ecs
->stop_func_start
;
3999 insert_step_resume_breakpoint_at_sal (gdbarch
,
4000 sr_sal
, null_frame_id
);
4003 /* Set a breakpoint at callee's return address (the address
4004 at which the caller will resume). */
4005 insert_step_resume_breakpoint_at_caller (frame
);
4011 /* Reverse stepping through solib trampolines. */
4013 if (execution_direction
== EXEC_REVERSE
4014 && ecs
->event_thread
->step_over_calls
!= STEP_OVER_NONE
)
4016 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4017 || (ecs
->stop_func_start
== 0
4018 && in_solib_dynsym_resolve_code (stop_pc
)))
4020 /* Any solib trampoline code can be handled in reverse
4021 by simply continuing to single-step. We have already
4022 executed the solib function (backwards), and a few
4023 steps will take us back through the trampoline to the
4028 else if (in_solib_dynsym_resolve_code (stop_pc
))
4030 /* Stepped backward into the solib dynsym resolver.
4031 Set a breakpoint at its start and continue, then
4032 one more step will take us out. */
4033 struct symtab_and_line sr_sal
;
4035 sr_sal
.pc
= ecs
->stop_func_start
;
4036 insert_step_resume_breakpoint_at_sal (gdbarch
,
4037 sr_sal
, null_frame_id
);
4043 /* If we're in the return path from a shared library trampoline,
4044 we want to proceed through the trampoline when stepping. */
4045 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4046 stop_pc
, ecs
->stop_func_name
))
4048 /* Determine where this trampoline returns. */
4049 CORE_ADDR real_stop_pc
;
4050 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4053 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
4055 /* Only proceed through if we know where it's going. */
4058 /* And put the step-breakpoint there and go until there. */
4059 struct symtab_and_line sr_sal
;
4061 init_sal (&sr_sal
); /* initialize to zeroes */
4062 sr_sal
.pc
= real_stop_pc
;
4063 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4065 /* Do not specify what the fp should be when we stop since
4066 on some machines the prologue is where the new fp value
4068 insert_step_resume_breakpoint_at_sal (gdbarch
,
4069 sr_sal
, null_frame_id
);
4071 /* Restart without fiddling with the step ranges or
4078 stop_pc_sal
= find_pc_line (stop_pc
, 0);
4080 /* NOTE: tausq/2004-05-24: This if block used to be done before all
4081 the trampoline processing logic, however, there are some trampolines
4082 that have no names, so we should do trampoline handling first. */
4083 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
4084 && ecs
->stop_func_name
== NULL
4085 && stop_pc_sal
.line
== 0)
4088 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
4090 /* The inferior just stepped into, or returned to, an
4091 undebuggable function (where there is no debugging information
4092 and no line number corresponding to the address where the
4093 inferior stopped). Since we want to skip this kind of code,
4094 we keep going until the inferior returns from this
4095 function - unless the user has asked us not to (via
4096 set step-mode) or we no longer know how to get back
4097 to the call site. */
4098 if (step_stop_if_no_debug
4099 || !frame_id_p (frame_unwind_caller_id (frame
)))
4101 /* If we have no line number and the step-stop-if-no-debug
4102 is set, we stop the step so that the user has a chance to
4103 switch in assembly mode. */
4104 ecs
->event_thread
->stop_step
= 1;
4105 print_stop_reason (END_STEPPING_RANGE
, 0);
4106 stop_stepping (ecs
);
4111 /* Set a breakpoint at callee's return address (the address
4112 at which the caller will resume). */
4113 insert_step_resume_breakpoint_at_caller (frame
);
4119 if (ecs
->event_thread
->step_range_end
== 1)
4121 /* It is stepi or nexti. We always want to stop stepping after
4124 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
4125 ecs
->event_thread
->stop_step
= 1;
4126 print_stop_reason (END_STEPPING_RANGE
, 0);
4127 stop_stepping (ecs
);
4131 if (stop_pc_sal
.line
== 0)
4133 /* We have no line number information. That means to stop
4134 stepping (does this always happen right after one instruction,
4135 when we do "s" in a function with no line numbers,
4136 or can this happen as a result of a return or longjmp?). */
4138 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
4139 ecs
->event_thread
->stop_step
= 1;
4140 print_stop_reason (END_STEPPING_RANGE
, 0);
4141 stop_stepping (ecs
);
4145 /* Look for "calls" to inlined functions, part one. If the inline
4146 frame machinery detected some skipped call sites, we have entered
4147 a new inline function. */
4149 if (frame_id_eq (get_frame_id (get_current_frame ()),
4150 ecs
->event_thread
->step_frame_id
)
4151 && inline_skipped_frames (ecs
->ptid
))
4153 struct symtab_and_line call_sal
;
4156 fprintf_unfiltered (gdb_stdlog
,
4157 "infrun: stepped into inlined function\n");
4159 find_frame_sal (get_current_frame (), &call_sal
);
4161 if (ecs
->event_thread
->step_over_calls
!= STEP_OVER_ALL
)
4163 /* For "step", we're going to stop. But if the call site
4164 for this inlined function is on the same source line as
4165 we were previously stepping, go down into the function
4166 first. Otherwise stop at the call site. */
4168 if (call_sal
.line
== ecs
->event_thread
->current_line
4169 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4170 step_into_inline_frame (ecs
->ptid
);
4172 ecs
->event_thread
->stop_step
= 1;
4173 print_stop_reason (END_STEPPING_RANGE
, 0);
4174 stop_stepping (ecs
);
4179 /* For "next", we should stop at the call site if it is on a
4180 different source line. Otherwise continue through the
4181 inlined function. */
4182 if (call_sal
.line
== ecs
->event_thread
->current_line
4183 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4187 ecs
->event_thread
->stop_step
= 1;
4188 print_stop_reason (END_STEPPING_RANGE
, 0);
4189 stop_stepping (ecs
);
4195 /* Look for "calls" to inlined functions, part two. If we are still
4196 in the same real function we were stepping through, but we have
4197 to go further up to find the exact frame ID, we are stepping
4198 through a more inlined call beyond its call site. */
4200 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
4201 && !frame_id_eq (get_frame_id (get_current_frame ()),
4202 ecs
->event_thread
->step_frame_id
)
4203 && stepped_in_from (get_current_frame (),
4204 ecs
->event_thread
->step_frame_id
))
4207 fprintf_unfiltered (gdb_stdlog
,
4208 "infrun: stepping through inlined function\n");
4210 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
4214 ecs
->event_thread
->stop_step
= 1;
4215 print_stop_reason (END_STEPPING_RANGE
, 0);
4216 stop_stepping (ecs
);
4221 if ((stop_pc
== stop_pc_sal
.pc
)
4222 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
4223 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
4225 /* We are at the start of a different line. So stop. Note that
4226 we don't stop if we step into the middle of a different line.
4227 That is said to make things like for (;;) statements work
4230 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
4231 ecs
->event_thread
->stop_step
= 1;
4232 print_stop_reason (END_STEPPING_RANGE
, 0);
4233 stop_stepping (ecs
);
4237 /* We aren't done stepping.
4239 Optimize by setting the stepping range to the line.
4240 (We might not be in the original line, but if we entered a
4241 new line in mid-statement, we continue stepping. This makes
4242 things like for(;;) statements work better.) */
4244 ecs
->event_thread
->step_range_start
= stop_pc_sal
.pc
;
4245 ecs
->event_thread
->step_range_end
= stop_pc_sal
.end
;
4246 set_step_info (frame
, stop_pc_sal
);
4249 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
4253 /* Is thread TP in the middle of single-stepping? */
4256 currently_stepping (struct thread_info
*tp
)
4258 return ((tp
->step_range_end
&& tp
->step_resume_breakpoint
== NULL
)
4259 || tp
->trap_expected
4260 || tp
->stepping_through_solib_after_catch
4261 || bpstat_should_step ());
4264 /* Returns true if any thread *but* the one passed in "data" is in the
4265 middle of stepping or of handling a "next". */
4268 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
4273 return (tp
->step_range_end
4274 || tp
->trap_expected
4275 || tp
->stepping_through_solib_after_catch
);
4278 /* Inferior has stepped into a subroutine call with source code that
4279 we should not step over. Do step to the first line of code in
4283 handle_step_into_function (struct gdbarch
*gdbarch
,
4284 struct execution_control_state
*ecs
)
4287 struct symtab_and_line stop_func_sal
, sr_sal
;
4289 s
= find_pc_symtab (stop_pc
);
4290 if (s
&& s
->language
!= language_asm
)
4291 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
4292 ecs
->stop_func_start
);
4294 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4295 /* Use the step_resume_break to step until the end of the prologue,
4296 even if that involves jumps (as it seems to on the vax under
4298 /* If the prologue ends in the middle of a source line, continue to
4299 the end of that source line (if it is still within the function).
4300 Otherwise, just go to end of prologue. */
4301 if (stop_func_sal
.end
4302 && stop_func_sal
.pc
!= ecs
->stop_func_start
4303 && stop_func_sal
.end
< ecs
->stop_func_end
)
4304 ecs
->stop_func_start
= stop_func_sal
.end
;
4306 /* Architectures which require breakpoint adjustment might not be able
4307 to place a breakpoint at the computed address. If so, the test
4308 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
4309 ecs->stop_func_start to an address at which a breakpoint may be
4310 legitimately placed.
4312 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
4313 made, GDB will enter an infinite loop when stepping through
4314 optimized code consisting of VLIW instructions which contain
4315 subinstructions corresponding to different source lines. On
4316 FR-V, it's not permitted to place a breakpoint on any but the
4317 first subinstruction of a VLIW instruction. When a breakpoint is
4318 set, GDB will adjust the breakpoint address to the beginning of
4319 the VLIW instruction. Thus, we need to make the corresponding
4320 adjustment here when computing the stop address. */
4322 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
4324 ecs
->stop_func_start
4325 = gdbarch_adjust_breakpoint_address (gdbarch
,
4326 ecs
->stop_func_start
);
4329 if (ecs
->stop_func_start
== stop_pc
)
4331 /* We are already there: stop now. */
4332 ecs
->event_thread
->stop_step
= 1;
4333 print_stop_reason (END_STEPPING_RANGE
, 0);
4334 stop_stepping (ecs
);
4339 /* Put the step-breakpoint there and go until there. */
4340 init_sal (&sr_sal
); /* initialize to zeroes */
4341 sr_sal
.pc
= ecs
->stop_func_start
;
4342 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
4344 /* Do not specify what the fp should be when we stop since on
4345 some machines the prologue is where the new fp value is
4347 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
4349 /* And make sure stepping stops right away then. */
4350 ecs
->event_thread
->step_range_end
= ecs
->event_thread
->step_range_start
;
4355 /* Inferior has stepped backward into a subroutine call with source
4356 code that we should not step over. Do step to the beginning of the
4357 last line of code in it. */
4360 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
4361 struct execution_control_state
*ecs
)
4364 struct symtab_and_line stop_func_sal
, sr_sal
;
4366 s
= find_pc_symtab (stop_pc
);
4367 if (s
&& s
->language
!= language_asm
)
4368 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
4369 ecs
->stop_func_start
);
4371 stop_func_sal
= find_pc_line (stop_pc
, 0);
4373 /* OK, we're just going to keep stepping here. */
4374 if (stop_func_sal
.pc
== stop_pc
)
4376 /* We're there already. Just stop stepping now. */
4377 ecs
->event_thread
->stop_step
= 1;
4378 print_stop_reason (END_STEPPING_RANGE
, 0);
4379 stop_stepping (ecs
);
4383 /* Else just reset the step range and keep going.
4384 No step-resume breakpoint, they don't work for
4385 epilogues, which can have multiple entry paths. */
4386 ecs
->event_thread
->step_range_start
= stop_func_sal
.pc
;
4387 ecs
->event_thread
->step_range_end
= stop_func_sal
.end
;
4393 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
4394 This is used to both functions and to skip over code. */
4397 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
4398 struct symtab_and_line sr_sal
,
4399 struct frame_id sr_id
)
4401 /* There should never be more than one step-resume or longjmp-resume
4402 breakpoint per thread, so we should never be setting a new
4403 step_resume_breakpoint when one is already active. */
4404 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
4407 fprintf_unfiltered (gdb_stdlog
,
4408 "infrun: inserting step-resume breakpoint at %s\n",
4409 paddress (gdbarch
, sr_sal
.pc
));
4411 inferior_thread ()->step_resume_breakpoint
4412 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, bp_step_resume
);
4415 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
4416 to skip a potential signal handler.
4418 This is called with the interrupted function's frame. The signal
4419 handler, when it returns, will resume the interrupted function at
4423 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
4425 struct symtab_and_line sr_sal
;
4426 struct gdbarch
*gdbarch
;
4428 gdb_assert (return_frame
!= NULL
);
4429 init_sal (&sr_sal
); /* initialize to zeros */
4431 gdbarch
= get_frame_arch (return_frame
);
4432 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
4433 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4435 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
4436 get_stack_frame_id (return_frame
));
4439 /* Similar to insert_step_resume_breakpoint_at_frame, except
4440 but a breakpoint at the previous frame's PC. This is used to
4441 skip a function after stepping into it (for "next" or if the called
4442 function has no debugging information).
4444 The current function has almost always been reached by single
4445 stepping a call or return instruction. NEXT_FRAME belongs to the
4446 current function, and the breakpoint will be set at the caller's
4449 This is a separate function rather than reusing
4450 insert_step_resume_breakpoint_at_frame in order to avoid
4451 get_prev_frame, which may stop prematurely (see the implementation
4452 of frame_unwind_caller_id for an example). */
4455 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
4457 struct symtab_and_line sr_sal
;
4458 struct gdbarch
*gdbarch
;
4460 /* We shouldn't have gotten here if we don't know where the call site
4462 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
4464 init_sal (&sr_sal
); /* initialize to zeros */
4466 gdbarch
= frame_unwind_caller_arch (next_frame
);
4467 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
4468 frame_unwind_caller_pc (next_frame
));
4469 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4471 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
4472 frame_unwind_caller_id (next_frame
));
4475 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
4476 new breakpoint at the target of a jmp_buf. The handling of
4477 longjmp-resume uses the same mechanisms used for handling
4478 "step-resume" breakpoints. */
4481 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
4483 /* There should never be more than one step-resume or longjmp-resume
4484 breakpoint per thread, so we should never be setting a new
4485 longjmp_resume_breakpoint when one is already active. */
4486 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
4489 fprintf_unfiltered (gdb_stdlog
,
4490 "infrun: inserting longjmp-resume breakpoint at %s\n",
4491 paddress (gdbarch
, pc
));
4493 inferior_thread ()->step_resume_breakpoint
=
4494 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
4498 stop_stepping (struct execution_control_state
*ecs
)
4501 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
4503 /* Let callers know we don't want to wait for the inferior anymore. */
4504 ecs
->wait_some_more
= 0;
4507 /* This function handles various cases where we need to continue
4508 waiting for the inferior. */
4509 /* (Used to be the keep_going: label in the old wait_for_inferior) */
4512 keep_going (struct execution_control_state
*ecs
)
4514 /* Save the pc before execution, to compare with pc after stop. */
4515 ecs
->event_thread
->prev_pc
4516 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4518 /* If we did not do break;, it means we should keep running the
4519 inferior and not return to debugger. */
4521 if (ecs
->event_thread
->trap_expected
4522 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
4524 /* We took a signal (which we are supposed to pass through to
4525 the inferior, else we'd not get here) and we haven't yet
4526 gotten our trap. Simply continue. */
4527 resume (currently_stepping (ecs
->event_thread
),
4528 ecs
->event_thread
->stop_signal
);
4532 /* Either the trap was not expected, but we are continuing
4533 anyway (the user asked that this signal be passed to the
4536 The signal was SIGTRAP, e.g. it was our signal, but we
4537 decided we should resume from it.
4539 We're going to run this baby now!
4541 Note that insert_breakpoints won't try to re-insert
4542 already inserted breakpoints. Therefore, we don't
4543 care if breakpoints were already inserted, or not. */
4545 if (ecs
->event_thread
->stepping_over_breakpoint
)
4547 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
4548 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
4549 /* Since we can't do a displaced step, we have to remove
4550 the breakpoint while we step it. To keep things
4551 simple, we remove them all. */
4552 remove_breakpoints ();
4556 struct gdb_exception e
;
4557 /* Stop stepping when inserting breakpoints
4559 TRY_CATCH (e
, RETURN_MASK_ERROR
)
4561 insert_breakpoints ();
4565 stop_stepping (ecs
);
4570 ecs
->event_thread
->trap_expected
= ecs
->event_thread
->stepping_over_breakpoint
;
4572 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
4573 specifies that such a signal should be delivered to the
4576 Typically, this would occure when a user is debugging a
4577 target monitor on a simulator: the target monitor sets a
4578 breakpoint; the simulator encounters this break-point and
4579 halts the simulation handing control to GDB; GDB, noteing
4580 that the break-point isn't valid, returns control back to the
4581 simulator; the simulator then delivers the hardware
4582 equivalent of a SIGNAL_TRAP to the program being debugged. */
4584 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
4585 && !signal_program
[ecs
->event_thread
->stop_signal
])
4586 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
4588 resume (currently_stepping (ecs
->event_thread
),
4589 ecs
->event_thread
->stop_signal
);
4592 prepare_to_wait (ecs
);
4595 /* This function normally comes after a resume, before
4596 handle_inferior_event exits. It takes care of any last bits of
4597 housekeeping, and sets the all-important wait_some_more flag. */
4600 prepare_to_wait (struct execution_control_state
*ecs
)
4603 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
4605 /* This is the old end of the while loop. Let everybody know we
4606 want to wait for the inferior some more and get called again
4608 ecs
->wait_some_more
= 1;
4611 /* Print why the inferior has stopped. We always print something when
4612 the inferior exits, or receives a signal. The rest of the cases are
4613 dealt with later on in normal_stop() and print_it_typical(). Ideally
4614 there should be a call to this function from handle_inferior_event()
4615 each time stop_stepping() is called.*/
4617 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
4619 switch (stop_reason
)
4621 case END_STEPPING_RANGE
:
4622 /* We are done with a step/next/si/ni command. */
4623 /* For now print nothing. */
4624 /* Print a message only if not in the middle of doing a "step n"
4625 operation for n > 1 */
4626 if (!inferior_thread ()->step_multi
4627 || !inferior_thread ()->stop_step
)
4628 if (ui_out_is_mi_like_p (uiout
))
4631 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
4634 /* The inferior was terminated by a signal. */
4635 annotate_signalled ();
4636 if (ui_out_is_mi_like_p (uiout
))
4639 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
4640 ui_out_text (uiout
, "\nProgram terminated with signal ");
4641 annotate_signal_name ();
4642 ui_out_field_string (uiout
, "signal-name",
4643 target_signal_to_name (stop_info
));
4644 annotate_signal_name_end ();
4645 ui_out_text (uiout
, ", ");
4646 annotate_signal_string ();
4647 ui_out_field_string (uiout
, "signal-meaning",
4648 target_signal_to_string (stop_info
));
4649 annotate_signal_string_end ();
4650 ui_out_text (uiout
, ".\n");
4651 ui_out_text (uiout
, "The program no longer exists.\n");
4654 /* The inferior program is finished. */
4655 annotate_exited (stop_info
);
4658 if (ui_out_is_mi_like_p (uiout
))
4659 ui_out_field_string (uiout
, "reason",
4660 async_reason_lookup (EXEC_ASYNC_EXITED
));
4661 ui_out_text (uiout
, "\nProgram exited with code ");
4662 ui_out_field_fmt (uiout
, "exit-code", "0%o",
4663 (unsigned int) stop_info
);
4664 ui_out_text (uiout
, ".\n");
4668 if (ui_out_is_mi_like_p (uiout
))
4671 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
4672 ui_out_text (uiout
, "\nProgram exited normally.\n");
4674 /* Support the --return-child-result option. */
4675 return_child_result_value
= stop_info
;
4677 case SIGNAL_RECEIVED
:
4678 /* Signal received. The signal table tells us to print about
4682 if (stop_info
== TARGET_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
4684 struct thread_info
*t
= inferior_thread ();
4686 ui_out_text (uiout
, "\n[");
4687 ui_out_field_string (uiout
, "thread-name",
4688 target_pid_to_str (t
->ptid
));
4689 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
4690 ui_out_text (uiout
, " stopped");
4694 ui_out_text (uiout
, "\nProgram received signal ");
4695 annotate_signal_name ();
4696 if (ui_out_is_mi_like_p (uiout
))
4698 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
4699 ui_out_field_string (uiout
, "signal-name",
4700 target_signal_to_name (stop_info
));
4701 annotate_signal_name_end ();
4702 ui_out_text (uiout
, ", ");
4703 annotate_signal_string ();
4704 ui_out_field_string (uiout
, "signal-meaning",
4705 target_signal_to_string (stop_info
));
4706 annotate_signal_string_end ();
4708 ui_out_text (uiout
, ".\n");
4711 /* Reverse execution: target ran out of history info. */
4712 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
4715 internal_error (__FILE__
, __LINE__
,
4716 _("print_stop_reason: unrecognized enum value"));
4722 /* Here to return control to GDB when the inferior stops for real.
4723 Print appropriate messages, remove breakpoints, give terminal our modes.
4725 STOP_PRINT_FRAME nonzero means print the executing frame
4726 (pc, function, args, file, line number and line text).
4727 BREAKPOINTS_FAILED nonzero means stop was due to error
4728 attempting to insert breakpoints. */
4733 struct target_waitstatus last
;
4735 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
4737 get_last_target_status (&last_ptid
, &last
);
4739 /* If an exception is thrown from this point on, make sure to
4740 propagate GDB's knowledge of the executing state to the
4741 frontend/user running state. A QUIT is an easy exception to see
4742 here, so do this before any filtered output. */
4744 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
4745 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
4746 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4747 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
4749 /* In non-stop mode, we don't want GDB to switch threads behind the
4750 user's back, to avoid races where the user is typing a command to
4751 apply to thread x, but GDB switches to thread y before the user
4752 finishes entering the command. */
4754 /* As with the notification of thread events, we want to delay
4755 notifying the user that we've switched thread context until
4756 the inferior actually stops.
4758 There's no point in saying anything if the inferior has exited.
4759 Note that SIGNALLED here means "exited with a signal", not
4760 "received a signal". */
4762 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
4763 && target_has_execution
4764 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
4765 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4767 target_terminal_ours_for_output ();
4768 printf_filtered (_("[Switching to %s]\n"),
4769 target_pid_to_str (inferior_ptid
));
4770 annotate_thread_changed ();
4771 previous_inferior_ptid
= inferior_ptid
;
4774 if (!breakpoints_always_inserted_mode () && target_has_execution
)
4776 if (remove_breakpoints ())
4778 target_terminal_ours_for_output ();
4779 printf_filtered (_("\
4780 Cannot remove breakpoints because program is no longer writable.\n\
4781 Further execution is probably impossible.\n"));
4785 /* If an auto-display called a function and that got a signal,
4786 delete that auto-display to avoid an infinite recursion. */
4788 if (stopped_by_random_signal
)
4789 disable_current_display ();
4791 /* Don't print a message if in the middle of doing a "step n"
4792 operation for n > 1 */
4793 if (target_has_execution
4794 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
4795 && last
.kind
!= TARGET_WAITKIND_EXITED
4796 && inferior_thread ()->step_multi
4797 && inferior_thread ()->stop_step
)
4800 target_terminal_ours ();
4802 /* Set the current source location. This will also happen if we
4803 display the frame below, but the current SAL will be incorrect
4804 during a user hook-stop function. */
4805 if (has_stack_frames () && !stop_stack_dummy
)
4806 set_current_sal_from_frame (get_current_frame (), 1);
4808 /* Let the user/frontend see the threads as stopped. */
4809 do_cleanups (old_chain
);
4811 /* Look up the hook_stop and run it (CLI internally handles problem
4812 of stop_command's pre-hook not existing). */
4814 catch_errors (hook_stop_stub
, stop_command
,
4815 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
4817 if (!has_stack_frames ())
4820 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
4821 || last
.kind
== TARGET_WAITKIND_EXITED
)
4824 /* Select innermost stack frame - i.e., current frame is frame 0,
4825 and current location is based on that.
4826 Don't do this on return from a stack dummy routine,
4827 or if the program has exited. */
4829 if (!stop_stack_dummy
)
4831 select_frame (get_current_frame ());
4833 /* Print current location without a level number, if
4834 we have changed functions or hit a breakpoint.
4835 Print source line if we have one.
4836 bpstat_print() contains the logic deciding in detail
4837 what to print, based on the event(s) that just occurred. */
4839 /* If --batch-silent is enabled then there's no need to print the current
4840 source location, and to try risks causing an error message about
4841 missing source files. */
4842 if (stop_print_frame
&& !batch_silent
)
4846 int do_frame_printing
= 1;
4847 struct thread_info
*tp
= inferior_thread ();
4849 bpstat_ret
= bpstat_print (tp
->stop_bpstat
);
4853 /* If we had hit a shared library event breakpoint,
4854 bpstat_print would print out this message. If we hit
4855 an OS-level shared library event, do the same
4857 if (last
.kind
== TARGET_WAITKIND_LOADED
)
4859 printf_filtered (_("Stopped due to shared library event\n"));
4860 source_flag
= SRC_LINE
; /* something bogus */
4861 do_frame_printing
= 0;
4865 /* FIXME: cagney/2002-12-01: Given that a frame ID does
4866 (or should) carry around the function and does (or
4867 should) use that when doing a frame comparison. */
4869 && frame_id_eq (tp
->step_frame_id
,
4870 get_frame_id (get_current_frame ()))
4871 && step_start_function
== find_pc_function (stop_pc
))
4872 source_flag
= SRC_LINE
; /* finished step, just print source line */
4874 source_flag
= SRC_AND_LOC
; /* print location and source line */
4876 case PRINT_SRC_AND_LOC
:
4877 source_flag
= SRC_AND_LOC
; /* print location and source line */
4879 case PRINT_SRC_ONLY
:
4880 source_flag
= SRC_LINE
;
4883 source_flag
= SRC_LINE
; /* something bogus */
4884 do_frame_printing
= 0;
4887 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
4890 /* The behavior of this routine with respect to the source
4892 SRC_LINE: Print only source line
4893 LOCATION: Print only location
4894 SRC_AND_LOC: Print location and source line */
4895 if (do_frame_printing
)
4896 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
4898 /* Display the auto-display expressions. */
4903 /* Save the function value return registers, if we care.
4904 We might be about to restore their previous contents. */
4905 if (inferior_thread ()->proceed_to_finish
)
4907 /* This should not be necessary. */
4909 regcache_xfree (stop_registers
);
4911 /* NB: The copy goes through to the target picking up the value of
4912 all the registers. */
4913 stop_registers
= regcache_dup (get_current_regcache ());
4916 if (stop_stack_dummy
)
4918 /* Pop the empty frame that contains the stack dummy.
4919 This also restores inferior state prior to the call
4920 (struct inferior_thread_state). */
4921 struct frame_info
*frame
= get_current_frame ();
4922 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
4924 /* frame_pop() calls reinit_frame_cache as the last thing it does
4925 which means there's currently no selected frame. We don't need
4926 to re-establish a selected frame if the dummy call returns normally,
4927 that will be done by restore_inferior_status. However, we do have
4928 to handle the case where the dummy call is returning after being
4929 stopped (e.g. the dummy call previously hit a breakpoint). We
4930 can't know which case we have so just always re-establish a
4931 selected frame here. */
4932 select_frame (get_current_frame ());
4936 annotate_stopped ();
4938 /* Suppress the stop observer if we're in the middle of:
4940 - a step n (n > 1), as there still more steps to be done.
4942 - a "finish" command, as the observer will be called in
4943 finish_command_continuation, so it can include the inferior
4944 function's return value.
4946 - calling an inferior function, as we pretend we inferior didn't
4947 run at all. The return value of the call is handled by the
4948 expression evaluator, through call_function_by_hand. */
4950 if (!target_has_execution
4951 || last
.kind
== TARGET_WAITKIND_SIGNALLED
4952 || last
.kind
== TARGET_WAITKIND_EXITED
4953 || (!inferior_thread ()->step_multi
4954 && !(inferior_thread ()->stop_bpstat
4955 && inferior_thread ()->proceed_to_finish
)
4956 && !inferior_thread ()->in_infcall
))
4958 if (!ptid_equal (inferior_ptid
, null_ptid
))
4959 observer_notify_normal_stop (inferior_thread ()->stop_bpstat
,
4962 observer_notify_normal_stop (NULL
, stop_print_frame
);
4965 if (target_has_execution
)
4967 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
4968 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4969 /* Delete the breakpoint we stopped at, if it wants to be deleted.
4970 Delete any breakpoint that is to be deleted at the next stop. */
4971 breakpoint_auto_delete (inferior_thread ()->stop_bpstat
);
4976 hook_stop_stub (void *cmd
)
4978 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
4983 signal_stop_state (int signo
)
4985 return signal_stop
[signo
];
4989 signal_print_state (int signo
)
4991 return signal_print
[signo
];
4995 signal_pass_state (int signo
)
4997 return signal_program
[signo
];
5001 signal_stop_update (int signo
, int state
)
5003 int ret
= signal_stop
[signo
];
5004 signal_stop
[signo
] = state
;
5009 signal_print_update (int signo
, int state
)
5011 int ret
= signal_print
[signo
];
5012 signal_print
[signo
] = state
;
5017 signal_pass_update (int signo
, int state
)
5019 int ret
= signal_program
[signo
];
5020 signal_program
[signo
] = state
;
5025 sig_print_header (void)
5027 printf_filtered (_("\
5028 Signal Stop\tPrint\tPass to program\tDescription\n"));
5032 sig_print_info (enum target_signal oursig
)
5034 const char *name
= target_signal_to_name (oursig
);
5035 int name_padding
= 13 - strlen (name
);
5037 if (name_padding
<= 0)
5040 printf_filtered ("%s", name
);
5041 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
5042 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
5043 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
5044 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
5045 printf_filtered ("%s\n", target_signal_to_string (oursig
));
5048 /* Specify how various signals in the inferior should be handled. */
5051 handle_command (char *args
, int from_tty
)
5054 int digits
, wordlen
;
5055 int sigfirst
, signum
, siglast
;
5056 enum target_signal oursig
;
5059 unsigned char *sigs
;
5060 struct cleanup
*old_chain
;
5064 error_no_arg (_("signal to handle"));
5067 /* Allocate and zero an array of flags for which signals to handle. */
5069 nsigs
= (int) TARGET_SIGNAL_LAST
;
5070 sigs
= (unsigned char *) alloca (nsigs
);
5071 memset (sigs
, 0, nsigs
);
5073 /* Break the command line up into args. */
5075 argv
= gdb_buildargv (args
);
5076 old_chain
= make_cleanup_freeargv (argv
);
5078 /* Walk through the args, looking for signal oursigs, signal names, and
5079 actions. Signal numbers and signal names may be interspersed with
5080 actions, with the actions being performed for all signals cumulatively
5081 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
5083 while (*argv
!= NULL
)
5085 wordlen
= strlen (*argv
);
5086 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
5090 sigfirst
= siglast
= -1;
5092 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
5094 /* Apply action to all signals except those used by the
5095 debugger. Silently skip those. */
5098 siglast
= nsigs
- 1;
5100 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
5102 SET_SIGS (nsigs
, sigs
, signal_stop
);
5103 SET_SIGS (nsigs
, sigs
, signal_print
);
5105 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
5107 UNSET_SIGS (nsigs
, sigs
, signal_program
);
5109 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
5111 SET_SIGS (nsigs
, sigs
, signal_print
);
5113 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
5115 SET_SIGS (nsigs
, sigs
, signal_program
);
5117 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
5119 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
5121 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
5123 SET_SIGS (nsigs
, sigs
, signal_program
);
5125 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
5127 UNSET_SIGS (nsigs
, sigs
, signal_print
);
5128 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
5130 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
5132 UNSET_SIGS (nsigs
, sigs
, signal_program
);
5134 else if (digits
> 0)
5136 /* It is numeric. The numeric signal refers to our own
5137 internal signal numbering from target.h, not to host/target
5138 signal number. This is a feature; users really should be
5139 using symbolic names anyway, and the common ones like
5140 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
5142 sigfirst
= siglast
= (int)
5143 target_signal_from_command (atoi (*argv
));
5144 if ((*argv
)[digits
] == '-')
5147 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
5149 if (sigfirst
> siglast
)
5151 /* Bet he didn't figure we'd think of this case... */
5159 oursig
= target_signal_from_name (*argv
);
5160 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
5162 sigfirst
= siglast
= (int) oursig
;
5166 /* Not a number and not a recognized flag word => complain. */
5167 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
5171 /* If any signal numbers or symbol names were found, set flags for
5172 which signals to apply actions to. */
5174 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
5176 switch ((enum target_signal
) signum
)
5178 case TARGET_SIGNAL_TRAP
:
5179 case TARGET_SIGNAL_INT
:
5180 if (!allsigs
&& !sigs
[signum
])
5182 if (query (_("%s is used by the debugger.\n\
5183 Are you sure you want to change it? "), target_signal_to_name ((enum target_signal
) signum
)))
5189 printf_unfiltered (_("Not confirmed, unchanged.\n"));
5190 gdb_flush (gdb_stdout
);
5194 case TARGET_SIGNAL_0
:
5195 case TARGET_SIGNAL_DEFAULT
:
5196 case TARGET_SIGNAL_UNKNOWN
:
5197 /* Make sure that "all" doesn't print these. */
5208 for (signum
= 0; signum
< nsigs
; signum
++)
5211 target_notice_signals (inferior_ptid
);
5215 /* Show the results. */
5216 sig_print_header ();
5217 for (; signum
< nsigs
; signum
++)
5219 sig_print_info (signum
);
5225 do_cleanups (old_chain
);
5229 xdb_handle_command (char *args
, int from_tty
)
5232 struct cleanup
*old_chain
;
5235 error_no_arg (_("xdb command"));
5237 /* Break the command line up into args. */
5239 argv
= gdb_buildargv (args
);
5240 old_chain
= make_cleanup_freeargv (argv
);
5241 if (argv
[1] != (char *) NULL
)
5246 bufLen
= strlen (argv
[0]) + 20;
5247 argBuf
= (char *) xmalloc (bufLen
);
5251 enum target_signal oursig
;
5253 oursig
= target_signal_from_name (argv
[0]);
5254 memset (argBuf
, 0, bufLen
);
5255 if (strcmp (argv
[1], "Q") == 0)
5256 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
5259 if (strcmp (argv
[1], "s") == 0)
5261 if (!signal_stop
[oursig
])
5262 sprintf (argBuf
, "%s %s", argv
[0], "stop");
5264 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
5266 else if (strcmp (argv
[1], "i") == 0)
5268 if (!signal_program
[oursig
])
5269 sprintf (argBuf
, "%s %s", argv
[0], "pass");
5271 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
5273 else if (strcmp (argv
[1], "r") == 0)
5275 if (!signal_print
[oursig
])
5276 sprintf (argBuf
, "%s %s", argv
[0], "print");
5278 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
5284 handle_command (argBuf
, from_tty
);
5286 printf_filtered (_("Invalid signal handling flag.\n"));
5291 do_cleanups (old_chain
);
5294 /* Print current contents of the tables set by the handle command.
5295 It is possible we should just be printing signals actually used
5296 by the current target (but for things to work right when switching
5297 targets, all signals should be in the signal tables). */
5300 signals_info (char *signum_exp
, int from_tty
)
5302 enum target_signal oursig
;
5303 sig_print_header ();
5307 /* First see if this is a symbol name. */
5308 oursig
= target_signal_from_name (signum_exp
);
5309 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
5311 /* No, try numeric. */
5313 target_signal_from_command (parse_and_eval_long (signum_exp
));
5315 sig_print_info (oursig
);
5319 printf_filtered ("\n");
5320 /* These ugly casts brought to you by the native VAX compiler. */
5321 for (oursig
= TARGET_SIGNAL_FIRST
;
5322 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
5323 oursig
= (enum target_signal
) ((int) oursig
+ 1))
5327 if (oursig
!= TARGET_SIGNAL_UNKNOWN
5328 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
5329 sig_print_info (oursig
);
5332 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
5335 /* The $_siginfo convenience variable is a bit special. We don't know
5336 for sure the type of the value until we actually have a chance to
5337 fetch the data. The type can change depending on gdbarch, so it it
5338 also dependent on which thread you have selected.
5340 1. making $_siginfo be an internalvar that creates a new value on
5343 2. making the value of $_siginfo be an lval_computed value. */
5345 /* This function implements the lval_computed support for reading a
5349 siginfo_value_read (struct value
*v
)
5351 LONGEST transferred
;
5354 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
5356 value_contents_all_raw (v
),
5358 TYPE_LENGTH (value_type (v
)));
5360 if (transferred
!= TYPE_LENGTH (value_type (v
)))
5361 error (_("Unable to read siginfo"));
5364 /* This function implements the lval_computed support for writing a
5368 siginfo_value_write (struct value
*v
, struct value
*fromval
)
5370 LONGEST transferred
;
5372 transferred
= target_write (¤t_target
,
5373 TARGET_OBJECT_SIGNAL_INFO
,
5375 value_contents_all_raw (fromval
),
5377 TYPE_LENGTH (value_type (fromval
)));
5379 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
5380 error (_("Unable to write siginfo"));
5383 static struct lval_funcs siginfo_value_funcs
=
5389 /* Return a new value with the correct type for the siginfo object of
5390 the current thread using architecture GDBARCH. Return a void value
5391 if there's no object available. */
5393 static struct value
*
5394 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
)
5396 if (target_has_stack
5397 && !ptid_equal (inferior_ptid
, null_ptid
)
5398 && gdbarch_get_siginfo_type_p (gdbarch
))
5400 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
5401 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
5404 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
5408 /* Inferior thread state.
5409 These are details related to the inferior itself, and don't include
5410 things like what frame the user had selected or what gdb was doing
5411 with the target at the time.
5412 For inferior function calls these are things we want to restore
5413 regardless of whether the function call successfully completes
5414 or the dummy frame has to be manually popped. */
5416 struct inferior_thread_state
5418 enum target_signal stop_signal
;
5420 struct regcache
*registers
;
5423 struct inferior_thread_state
*
5424 save_inferior_thread_state (void)
5426 struct inferior_thread_state
*inf_state
= XMALLOC (struct inferior_thread_state
);
5427 struct thread_info
*tp
= inferior_thread ();
5429 inf_state
->stop_signal
= tp
->stop_signal
;
5430 inf_state
->stop_pc
= stop_pc
;
5432 inf_state
->registers
= regcache_dup (get_current_regcache ());
5437 /* Restore inferior session state to INF_STATE. */
5440 restore_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5442 struct thread_info
*tp
= inferior_thread ();
5444 tp
->stop_signal
= inf_state
->stop_signal
;
5445 stop_pc
= inf_state
->stop_pc
;
5447 /* The inferior can be gone if the user types "print exit(0)"
5448 (and perhaps other times). */
5449 if (target_has_execution
)
5450 /* NB: The register write goes through to the target. */
5451 regcache_cpy (get_current_regcache (), inf_state
->registers
);
5452 regcache_xfree (inf_state
->registers
);
5457 do_restore_inferior_thread_state_cleanup (void *state
)
5459 restore_inferior_thread_state (state
);
5463 make_cleanup_restore_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5465 return make_cleanup (do_restore_inferior_thread_state_cleanup
, inf_state
);
5469 discard_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5471 regcache_xfree (inf_state
->registers
);
5476 get_inferior_thread_state_regcache (struct inferior_thread_state
*inf_state
)
5478 return inf_state
->registers
;
5481 /* Session related state for inferior function calls.
5482 These are the additional bits of state that need to be restored
5483 when an inferior function call successfully completes. */
5485 struct inferior_status
5489 int stop_stack_dummy
;
5490 int stopped_by_random_signal
;
5491 int stepping_over_breakpoint
;
5492 CORE_ADDR step_range_start
;
5493 CORE_ADDR step_range_end
;
5494 struct frame_id step_frame_id
;
5495 struct frame_id step_stack_frame_id
;
5496 enum step_over_calls_kind step_over_calls
;
5497 CORE_ADDR step_resume_break_address
;
5498 int stop_after_trap
;
5501 /* ID if the selected frame when the inferior function call was made. */
5502 struct frame_id selected_frame_id
;
5504 int proceed_to_finish
;
5508 /* Save all of the information associated with the inferior<==>gdb
5511 struct inferior_status
*
5512 save_inferior_status (void)
5514 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
5515 struct thread_info
*tp
= inferior_thread ();
5516 struct inferior
*inf
= current_inferior ();
5518 inf_status
->stop_step
= tp
->stop_step
;
5519 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
5520 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
5521 inf_status
->stepping_over_breakpoint
= tp
->trap_expected
;
5522 inf_status
->step_range_start
= tp
->step_range_start
;
5523 inf_status
->step_range_end
= tp
->step_range_end
;
5524 inf_status
->step_frame_id
= tp
->step_frame_id
;
5525 inf_status
->step_stack_frame_id
= tp
->step_stack_frame_id
;
5526 inf_status
->step_over_calls
= tp
->step_over_calls
;
5527 inf_status
->stop_after_trap
= stop_after_trap
;
5528 inf_status
->stop_soon
= inf
->stop_soon
;
5529 /* Save original bpstat chain here; replace it with copy of chain.
5530 If caller's caller is walking the chain, they'll be happier if we
5531 hand them back the original chain when restore_inferior_status is
5533 inf_status
->stop_bpstat
= tp
->stop_bpstat
;
5534 tp
->stop_bpstat
= bpstat_copy (tp
->stop_bpstat
);
5535 inf_status
->proceed_to_finish
= tp
->proceed_to_finish
;
5536 inf_status
->in_infcall
= tp
->in_infcall
;
5538 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
5544 restore_selected_frame (void *args
)
5546 struct frame_id
*fid
= (struct frame_id
*) args
;
5547 struct frame_info
*frame
;
5549 frame
= frame_find_by_id (*fid
);
5551 /* If inf_status->selected_frame_id is NULL, there was no previously
5555 warning (_("Unable to restore previously selected frame."));
5559 select_frame (frame
);
5564 /* Restore inferior session state to INF_STATUS. */
5567 restore_inferior_status (struct inferior_status
*inf_status
)
5569 struct thread_info
*tp
= inferior_thread ();
5570 struct inferior
*inf
= current_inferior ();
5572 tp
->stop_step
= inf_status
->stop_step
;
5573 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
5574 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
5575 tp
->trap_expected
= inf_status
->stepping_over_breakpoint
;
5576 tp
->step_range_start
= inf_status
->step_range_start
;
5577 tp
->step_range_end
= inf_status
->step_range_end
;
5578 tp
->step_frame_id
= inf_status
->step_frame_id
;
5579 tp
->step_stack_frame_id
= inf_status
->step_stack_frame_id
;
5580 tp
->step_over_calls
= inf_status
->step_over_calls
;
5581 stop_after_trap
= inf_status
->stop_after_trap
;
5582 inf
->stop_soon
= inf_status
->stop_soon
;
5583 bpstat_clear (&tp
->stop_bpstat
);
5584 tp
->stop_bpstat
= inf_status
->stop_bpstat
;
5585 inf_status
->stop_bpstat
= NULL
;
5586 tp
->proceed_to_finish
= inf_status
->proceed_to_finish
;
5587 tp
->in_infcall
= inf_status
->in_infcall
;
5589 if (target_has_stack
)
5591 /* The point of catch_errors is that if the stack is clobbered,
5592 walking the stack might encounter a garbage pointer and
5593 error() trying to dereference it. */
5595 (restore_selected_frame
, &inf_status
->selected_frame_id
,
5596 "Unable to restore previously selected frame:\n",
5597 RETURN_MASK_ERROR
) == 0)
5598 /* Error in restoring the selected frame. Select the innermost
5600 select_frame (get_current_frame ());
5607 do_restore_inferior_status_cleanup (void *sts
)
5609 restore_inferior_status (sts
);
5613 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
5615 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
5619 discard_inferior_status (struct inferior_status
*inf_status
)
5621 /* See save_inferior_status for info on stop_bpstat. */
5622 bpstat_clear (&inf_status
->stop_bpstat
);
5627 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
5629 struct target_waitstatus last
;
5632 get_last_target_status (&last_ptid
, &last
);
5634 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
5637 if (!ptid_equal (last_ptid
, pid
))
5640 *child_pid
= last
.value
.related_pid
;
5645 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
5647 struct target_waitstatus last
;
5650 get_last_target_status (&last_ptid
, &last
);
5652 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
5655 if (!ptid_equal (last_ptid
, pid
))
5658 *child_pid
= last
.value
.related_pid
;
5663 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
5665 struct target_waitstatus last
;
5668 get_last_target_status (&last_ptid
, &last
);
5670 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
5673 if (!ptid_equal (last_ptid
, pid
))
5676 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
5681 inferior_has_called_syscall (ptid_t pid
, int *syscall_number
)
5683 struct target_waitstatus last
;
5686 get_last_target_status (&last_ptid
, &last
);
5688 if (last
.kind
!= TARGET_WAITKIND_SYSCALL_ENTRY
&&
5689 last
.kind
!= TARGET_WAITKIND_SYSCALL_RETURN
)
5692 if (!ptid_equal (last_ptid
, pid
))
5695 *syscall_number
= last
.value
.syscall_number
;
5699 /* Oft used ptids */
5701 ptid_t minus_one_ptid
;
5703 /* Create a ptid given the necessary PID, LWP, and TID components. */
5706 ptid_build (int pid
, long lwp
, long tid
)
5716 /* Create a ptid from just a pid. */
5719 pid_to_ptid (int pid
)
5721 return ptid_build (pid
, 0, 0);
5724 /* Fetch the pid (process id) component from a ptid. */
5727 ptid_get_pid (ptid_t ptid
)
5732 /* Fetch the lwp (lightweight process) component from a ptid. */
5735 ptid_get_lwp (ptid_t ptid
)
5740 /* Fetch the tid (thread id) component from a ptid. */
5743 ptid_get_tid (ptid_t ptid
)
5748 /* ptid_equal() is used to test equality of two ptids. */
5751 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
5753 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
5754 && ptid1
.tid
== ptid2
.tid
);
5757 /* Returns true if PTID represents a process. */
5760 ptid_is_pid (ptid_t ptid
)
5762 if (ptid_equal (minus_one_ptid
, ptid
))
5764 if (ptid_equal (null_ptid
, ptid
))
5767 return (ptid_get_lwp (ptid
) == 0 && ptid_get_tid (ptid
) == 0);
5770 /* restore_inferior_ptid() will be used by the cleanup machinery
5771 to restore the inferior_ptid value saved in a call to
5772 save_inferior_ptid(). */
5775 restore_inferior_ptid (void *arg
)
5777 ptid_t
*saved_ptid_ptr
= arg
;
5778 inferior_ptid
= *saved_ptid_ptr
;
5782 /* Save the value of inferior_ptid so that it may be restored by a
5783 later call to do_cleanups(). Returns the struct cleanup pointer
5784 needed for later doing the cleanup. */
5787 save_inferior_ptid (void)
5789 ptid_t
*saved_ptid_ptr
;
5791 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
5792 *saved_ptid_ptr
= inferior_ptid
;
5793 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
5797 /* User interface for reverse debugging:
5798 Set exec-direction / show exec-direction commands
5799 (returns error unless target implements to_set_exec_direction method). */
5801 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
5802 static const char exec_forward
[] = "forward";
5803 static const char exec_reverse
[] = "reverse";
5804 static const char *exec_direction
= exec_forward
;
5805 static const char *exec_direction_names
[] = {
5812 set_exec_direction_func (char *args
, int from_tty
,
5813 struct cmd_list_element
*cmd
)
5815 if (target_can_execute_reverse
)
5817 if (!strcmp (exec_direction
, exec_forward
))
5818 execution_direction
= EXEC_FORWARD
;
5819 else if (!strcmp (exec_direction
, exec_reverse
))
5820 execution_direction
= EXEC_REVERSE
;
5825 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
5826 struct cmd_list_element
*cmd
, const char *value
)
5828 switch (execution_direction
) {
5830 fprintf_filtered (out
, _("Forward.\n"));
5833 fprintf_filtered (out
, _("Reverse.\n"));
5837 fprintf_filtered (out
,
5838 _("Forward (target `%s' does not support exec-direction).\n"),
5844 /* User interface for non-stop mode. */
5847 static int non_stop_1
= 0;
5850 set_non_stop (char *args
, int from_tty
,
5851 struct cmd_list_element
*c
)
5853 if (target_has_execution
)
5855 non_stop_1
= non_stop
;
5856 error (_("Cannot change this setting while the inferior is running."));
5859 non_stop
= non_stop_1
;
5863 show_non_stop (struct ui_file
*file
, int from_tty
,
5864 struct cmd_list_element
*c
, const char *value
)
5866 fprintf_filtered (file
,
5867 _("Controlling the inferior in non-stop mode is %s.\n"),
5872 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
5873 struct cmd_list_element
*c
, const char *value
)
5875 fprintf_filtered (file
, _("\
5876 Resuming the execution of threads of all processes is %s.\n"), value
);
5880 _initialize_infrun (void)
5884 struct cmd_list_element
*c
;
5886 add_info ("signals", signals_info
, _("\
5887 What debugger does when program gets various signals.\n\
5888 Specify a signal as argument to print info on that signal only."));
5889 add_info_alias ("handle", "signals", 0);
5891 add_com ("handle", class_run
, handle_command
, _("\
5892 Specify how to handle a signal.\n\
5893 Args are signals and actions to apply to those signals.\n\
5894 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
5895 from 1-15 are allowed for compatibility with old versions of GDB.\n\
5896 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
5897 The special arg \"all\" is recognized to mean all signals except those\n\
5898 used by the debugger, typically SIGTRAP and SIGINT.\n\
5899 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
5900 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
5901 Stop means reenter debugger if this signal happens (implies print).\n\
5902 Print means print a message if this signal happens.\n\
5903 Pass means let program see this signal; otherwise program doesn't know.\n\
5904 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
5905 Pass and Stop may be combined."));
5908 add_com ("lz", class_info
, signals_info
, _("\
5909 What debugger does when program gets various signals.\n\
5910 Specify a signal as argument to print info on that signal only."));
5911 add_com ("z", class_run
, xdb_handle_command
, _("\
5912 Specify how to handle a signal.\n\
5913 Args are signals and actions to apply to those signals.\n\
5914 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
5915 from 1-15 are allowed for compatibility with old versions of GDB.\n\
5916 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
5917 The special arg \"all\" is recognized to mean all signals except those\n\
5918 used by the debugger, typically SIGTRAP and SIGINT.\n\
5919 Recognized actions include \"s\" (toggles between stop and nostop), \n\
5920 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
5921 nopass), \"Q\" (noprint)\n\
5922 Stop means reenter debugger if this signal happens (implies print).\n\
5923 Print means print a message if this signal happens.\n\
5924 Pass means let program see this signal; otherwise program doesn't know.\n\
5925 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
5926 Pass and Stop may be combined."));
5930 stop_command
= add_cmd ("stop", class_obscure
,
5931 not_just_help_class_command
, _("\
5932 There is no `stop' command, but you can set a hook on `stop'.\n\
5933 This allows you to set a list of commands to be run each time execution\n\
5934 of the program stops."), &cmdlist
);
5936 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
5937 Set inferior debugging."), _("\
5938 Show inferior debugging."), _("\
5939 When non-zero, inferior specific debugging is enabled."),
5942 &setdebuglist
, &showdebuglist
);
5944 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
5945 Set displaced stepping debugging."), _("\
5946 Show displaced stepping debugging."), _("\
5947 When non-zero, displaced stepping specific debugging is enabled."),
5949 show_debug_displaced
,
5950 &setdebuglist
, &showdebuglist
);
5952 add_setshow_boolean_cmd ("non-stop", no_class
,
5954 Set whether gdb controls the inferior in non-stop mode."), _("\
5955 Show whether gdb controls the inferior in non-stop mode."), _("\
5956 When debugging a multi-threaded program and this setting is\n\
5957 off (the default, also called all-stop mode), when one thread stops\n\
5958 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
5959 all other threads in the program while you interact with the thread of\n\
5960 interest. When you continue or step a thread, you can allow the other\n\
5961 threads to run, or have them remain stopped, but while you inspect any\n\
5962 thread's state, all threads stop.\n\
5964 In non-stop mode, when one thread stops, other threads can continue\n\
5965 to run freely. You'll be able to step each thread independently,\n\
5966 leave it stopped or free to run as needed."),
5972 numsigs
= (int) TARGET_SIGNAL_LAST
;
5973 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
5974 signal_print
= (unsigned char *)
5975 xmalloc (sizeof (signal_print
[0]) * numsigs
);
5976 signal_program
= (unsigned char *)
5977 xmalloc (sizeof (signal_program
[0]) * numsigs
);
5978 for (i
= 0; i
< numsigs
; i
++)
5981 signal_print
[i
] = 1;
5982 signal_program
[i
] = 1;
5985 /* Signals caused by debugger's own actions
5986 should not be given to the program afterwards. */
5987 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
5988 signal_program
[TARGET_SIGNAL_INT
] = 0;
5990 /* Signals that are not errors should not normally enter the debugger. */
5991 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
5992 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
5993 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
5994 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
5995 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
5996 signal_print
[TARGET_SIGNAL_PROF
] = 0;
5997 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
5998 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
5999 signal_stop
[TARGET_SIGNAL_IO
] = 0;
6000 signal_print
[TARGET_SIGNAL_IO
] = 0;
6001 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
6002 signal_print
[TARGET_SIGNAL_POLL
] = 0;
6003 signal_stop
[TARGET_SIGNAL_URG
] = 0;
6004 signal_print
[TARGET_SIGNAL_URG
] = 0;
6005 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
6006 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
6008 /* These signals are used internally by user-level thread
6009 implementations. (See signal(5) on Solaris.) Like the above
6010 signals, a healthy program receives and handles them as part of
6011 its normal operation. */
6012 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
6013 signal_print
[TARGET_SIGNAL_LWP
] = 0;
6014 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
6015 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
6016 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
6017 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
6019 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
6020 &stop_on_solib_events
, _("\
6021 Set stopping for shared library events."), _("\
6022 Show stopping for shared library events."), _("\
6023 If nonzero, gdb will give control to the user when the dynamic linker\n\
6024 notifies gdb of shared library events. The most common event of interest\n\
6025 to the user would be loading/unloading of a new library."),
6027 show_stop_on_solib_events
,
6028 &setlist
, &showlist
);
6030 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
6031 follow_fork_mode_kind_names
,
6032 &follow_fork_mode_string
, _("\
6033 Set debugger response to a program call of fork or vfork."), _("\
6034 Show debugger response to a program call of fork or vfork."), _("\
6035 A fork or vfork creates a new process. follow-fork-mode can be:\n\
6036 parent - the original process is debugged after a fork\n\
6037 child - the new process is debugged after a fork\n\
6038 The unfollowed process will continue to run.\n\
6039 By default, the debugger will follow the parent process."),
6041 show_follow_fork_mode_string
,
6042 &setlist
, &showlist
);
6044 add_setshow_enum_cmd ("scheduler-locking", class_run
,
6045 scheduler_enums
, &scheduler_mode
, _("\
6046 Set mode for locking scheduler during execution."), _("\
6047 Show mode for locking scheduler during execution."), _("\
6048 off == no locking (threads may preempt at any time)\n\
6049 on == full locking (no thread except the current thread may run)\n\
6050 step == scheduler locked during every single-step operation.\n\
6051 In this mode, no other thread may run during a step command.\n\
6052 Other threads may run while stepping over a function call ('next')."),
6053 set_schedlock_func
, /* traps on target vector */
6054 show_scheduler_mode
,
6055 &setlist
, &showlist
);
6057 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
6058 Set mode for resuming threads of all processes."), _("\
6059 Show mode for resuming threads of all processes."), _("\
6060 When on, execution commands (such as 'continue' or 'next') resume all\n\
6061 threads of all processes. When off (which is the default), execution\n\
6062 commands only resume the threads of the current process. The set of\n\
6063 threads that are resumed is further refined by the scheduler-locking\n\
6064 mode (see help set scheduler-locking)."),
6066 show_schedule_multiple
,
6067 &setlist
, &showlist
);
6069 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
6070 Set mode of the step operation."), _("\
6071 Show mode of the step operation."), _("\
6072 When set, doing a step over a function without debug line information\n\
6073 will stop at the first instruction of that function. Otherwise, the\n\
6074 function is skipped and the step command stops at a different source line."),
6076 show_step_stop_if_no_debug
,
6077 &setlist
, &showlist
);
6079 add_setshow_enum_cmd ("displaced-stepping", class_run
,
6080 can_use_displaced_stepping_enum
,
6081 &can_use_displaced_stepping
, _("\
6082 Set debugger's willingness to use displaced stepping."), _("\
6083 Show debugger's willingness to use displaced stepping."), _("\
6084 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
6085 supported by the target architecture. If off, gdb will not use displaced\n\
6086 stepping to step over breakpoints, even if such is supported by the target\n\
6087 architecture. If auto (which is the default), gdb will use displaced stepping\n\
6088 if the target architecture supports it and non-stop mode is active, but will not\n\
6089 use it in all-stop mode (see help set non-stop)."),
6091 show_can_use_displaced_stepping
,
6092 &setlist
, &showlist
);
6094 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
6095 &exec_direction
, _("Set direction of execution.\n\
6096 Options are 'forward' or 'reverse'."),
6097 _("Show direction of execution (forward/reverse)."),
6098 _("Tells gdb whether to execute forward or backward."),
6099 set_exec_direction_func
, show_exec_direction_func
,
6100 &setlist
, &showlist
);
6102 /* ptid initializations */
6103 null_ptid
= ptid_build (0, 0, 0);
6104 minus_one_ptid
= ptid_build (-1, 0, 0);
6105 inferior_ptid
= null_ptid
;
6106 target_last_wait_ptid
= minus_one_ptid
;
6107 displaced_step_ptid
= null_ptid
;
6109 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
6110 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
6111 observer_attach_thread_exit (infrun_thread_thread_exit
);
6113 /* Explicitly create without lookup, since that tries to create a
6114 value with a void typed value, and when we get here, gdbarch
6115 isn't initialized yet. At this point, we're quite sure there
6116 isn't another convenience variable of the same name. */
6117 create_internalvar_type_lazy ("_siginfo", siginfo_make_value
);