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"
54 /* Prototypes for local functions */
56 static void signals_info (char *, int);
58 static void handle_command (char *, int);
60 static void sig_print_info (enum target_signal
);
62 static void sig_print_header (void);
64 static void resume_cleanups (void *);
66 static int hook_stop_stub (void *);
68 static int restore_selected_frame (void *);
70 static void build_infrun (void);
72 static int follow_fork (void);
74 static void set_schedlock_func (char *args
, int from_tty
,
75 struct cmd_list_element
*c
);
77 static int currently_stepping (struct thread_info
*tp
);
79 static int currently_stepping_or_nexting_callback (struct thread_info
*tp
,
82 static void xdb_handle_command (char *args
, int from_tty
);
84 static int prepare_to_proceed (int);
86 void _initialize_infrun (void);
88 void nullify_last_target_wait_ptid (void);
90 /* When set, stop the 'step' command if we enter a function which has
91 no line number information. The normal behavior is that we step
92 over such function. */
93 int step_stop_if_no_debug
= 0;
95 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
96 struct cmd_list_element
*c
, const char *value
)
98 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
101 /* In asynchronous mode, but simulating synchronous execution. */
103 int sync_execution
= 0;
105 /* wait_for_inferior and normal_stop use this to notify the user
106 when the inferior stopped in a different thread than it had been
109 static ptid_t previous_inferior_ptid
;
111 int debug_displaced
= 0;
113 show_debug_displaced (struct ui_file
*file
, int from_tty
,
114 struct cmd_list_element
*c
, const char *value
)
116 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
119 static int debug_infrun
= 0;
121 show_debug_infrun (struct ui_file
*file
, int from_tty
,
122 struct cmd_list_element
*c
, const char *value
)
124 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
127 /* If the program uses ELF-style shared libraries, then calls to
128 functions in shared libraries go through stubs, which live in a
129 table called the PLT (Procedure Linkage Table). The first time the
130 function is called, the stub sends control to the dynamic linker,
131 which looks up the function's real address, patches the stub so
132 that future calls will go directly to the function, and then passes
133 control to the function.
135 If we are stepping at the source level, we don't want to see any of
136 this --- we just want to skip over the stub and the dynamic linker.
137 The simple approach is to single-step until control leaves the
140 However, on some systems (e.g., Red Hat's 5.2 distribution) the
141 dynamic linker calls functions in the shared C library, so you
142 can't tell from the PC alone whether the dynamic linker is still
143 running. In this case, we use a step-resume breakpoint to get us
144 past the dynamic linker, as if we were using "next" to step over a
147 in_solib_dynsym_resolve_code() says whether we're in the dynamic
148 linker code or not. Normally, this means we single-step. However,
149 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
150 address where we can place a step-resume breakpoint to get past the
151 linker's symbol resolution function.
153 in_solib_dynsym_resolve_code() can generally be implemented in a
154 pretty portable way, by comparing the PC against the address ranges
155 of the dynamic linker's sections.
157 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
158 it depends on internal details of the dynamic linker. It's usually
159 not too hard to figure out where to put a breakpoint, but it
160 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
161 sanity checking. If it can't figure things out, returning zero and
162 getting the (possibly confusing) stepping behavior is better than
163 signalling an error, which will obscure the change in the
166 /* This function returns TRUE if pc is the address of an instruction
167 that lies within the dynamic linker (such as the event hook, or the
170 This function must be used only when a dynamic linker event has
171 been caught, and the inferior is being stepped out of the hook, or
172 undefined results are guaranteed. */
174 #ifndef SOLIB_IN_DYNAMIC_LINKER
175 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
179 /* Convert the #defines into values. This is temporary until wfi control
180 flow is completely sorted out. */
182 #ifndef CANNOT_STEP_HW_WATCHPOINTS
183 #define CANNOT_STEP_HW_WATCHPOINTS 0
185 #undef CANNOT_STEP_HW_WATCHPOINTS
186 #define CANNOT_STEP_HW_WATCHPOINTS 1
189 /* Tables of how to react to signals; the user sets them. */
191 static unsigned char *signal_stop
;
192 static unsigned char *signal_print
;
193 static unsigned char *signal_program
;
195 #define SET_SIGS(nsigs,sigs,flags) \
197 int signum = (nsigs); \
198 while (signum-- > 0) \
199 if ((sigs)[signum]) \
200 (flags)[signum] = 1; \
203 #define UNSET_SIGS(nsigs,sigs,flags) \
205 int signum = (nsigs); \
206 while (signum-- > 0) \
207 if ((sigs)[signum]) \
208 (flags)[signum] = 0; \
211 /* Value to pass to target_resume() to cause all threads to resume */
213 #define RESUME_ALL minus_one_ptid
215 /* Command list pointer for the "stop" placeholder. */
217 static struct cmd_list_element
*stop_command
;
219 /* Function inferior was in as of last step command. */
221 static struct symbol
*step_start_function
;
223 /* Nonzero if we want to give control to the user when we're notified
224 of shared library events by the dynamic linker. */
225 static int stop_on_solib_events
;
227 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
228 struct cmd_list_element
*c
, const char *value
)
230 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
234 /* Nonzero means expecting a trace trap
235 and should stop the inferior and return silently when it happens. */
239 /* Save register contents here when executing a "finish" command or are
240 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
241 Thus this contains the return value from the called function (assuming
242 values are returned in a register). */
244 struct regcache
*stop_registers
;
246 /* Nonzero after stop if current stack frame should be printed. */
248 static int stop_print_frame
;
250 /* This is a cached copy of the pid/waitstatus of the last event
251 returned by target_wait()/deprecated_target_wait_hook(). This
252 information is returned by get_last_target_status(). */
253 static ptid_t target_last_wait_ptid
;
254 static struct target_waitstatus target_last_waitstatus
;
256 static void context_switch (ptid_t ptid
);
258 void init_thread_stepping_state (struct thread_info
*tss
);
260 void init_infwait_state (void);
262 static const char follow_fork_mode_child
[] = "child";
263 static const char follow_fork_mode_parent
[] = "parent";
265 static const char *follow_fork_mode_kind_names
[] = {
266 follow_fork_mode_child
,
267 follow_fork_mode_parent
,
271 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
273 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
274 struct cmd_list_element
*c
, const char *value
)
276 fprintf_filtered (file
, _("\
277 Debugger response to a program call of fork or vfork is \"%s\".\n"),
282 /* Tell the target to follow the fork we're stopped at. Returns true
283 if the inferior should be resumed; false, if the target for some
284 reason decided it's best not to resume. */
289 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
290 int should_resume
= 1;
291 struct thread_info
*tp
;
293 /* Copy user stepping state to the new inferior thread. FIXME: the
294 followed fork child thread should have a copy of most of the
295 parent thread structure's run control related fields, not just these.
296 Initialized to avoid "may be used uninitialized" warnings from gcc. */
297 struct breakpoint
*step_resume_breakpoint
= NULL
;
298 CORE_ADDR step_range_start
= 0;
299 CORE_ADDR step_range_end
= 0;
300 struct frame_id step_frame_id
= { 0 };
305 struct target_waitstatus wait_status
;
307 /* Get the last target status returned by target_wait(). */
308 get_last_target_status (&wait_ptid
, &wait_status
);
310 /* If not stopped at a fork event, then there's nothing else to
312 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
313 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
316 /* Check if we switched over from WAIT_PTID, since the event was
318 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
319 && !ptid_equal (inferior_ptid
, wait_ptid
))
321 /* We did. Switch back to WAIT_PTID thread, to tell the
322 target to follow it (in either direction). We'll
323 afterwards refuse to resume, and inform the user what
325 switch_to_thread (wait_ptid
);
330 tp
= inferior_thread ();
332 /* If there were any forks/vforks that were caught and are now to be
333 followed, then do so now. */
334 switch (tp
->pending_follow
.kind
)
336 case TARGET_WAITKIND_FORKED
:
337 case TARGET_WAITKIND_VFORKED
:
339 ptid_t parent
, child
;
341 /* If the user did a next/step, etc, over a fork call,
342 preserve the stepping state in the fork child. */
343 if (follow_child
&& should_resume
)
345 step_resume_breakpoint
346 = clone_momentary_breakpoint (tp
->step_resume_breakpoint
);
347 step_range_start
= tp
->step_range_start
;
348 step_range_end
= tp
->step_range_end
;
349 step_frame_id
= tp
->step_frame_id
;
351 /* For now, delete the parent's sr breakpoint, otherwise,
352 parent/child sr breakpoints are considered duplicates,
353 and the child version will not be installed. Remove
354 this when the breakpoints module becomes aware of
355 inferiors and address spaces. */
356 delete_step_resume_breakpoint (tp
);
357 tp
->step_range_start
= 0;
358 tp
->step_range_end
= 0;
359 tp
->step_frame_id
= null_frame_id
;
362 parent
= inferior_ptid
;
363 child
= tp
->pending_follow
.value
.related_pid
;
365 /* Tell the target to do whatever is necessary to follow
366 either parent or child. */
367 if (target_follow_fork (follow_child
))
369 /* Target refused to follow, or there's some other reason
370 we shouldn't resume. */
375 /* This pending follow fork event is now handled, one way
376 or another. The previous selected thread may be gone
377 from the lists by now, but if it is still around, need
378 to clear the pending follow request. */
379 tp
= find_thread_ptid (parent
);
381 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
383 /* This makes sure we don't try to apply the "Switched
384 over from WAIT_PID" logic above. */
385 nullify_last_target_wait_ptid ();
387 /* If we followed the child, switch to it... */
390 switch_to_thread (child
);
392 /* ... and preserve the stepping state, in case the
393 user was stepping over the fork call. */
396 tp
= inferior_thread ();
397 tp
->step_resume_breakpoint
= step_resume_breakpoint
;
398 tp
->step_range_start
= step_range_start
;
399 tp
->step_range_end
= step_range_end
;
400 tp
->step_frame_id
= step_frame_id
;
404 /* If we get here, it was because we're trying to
405 resume from a fork catchpoint, but, the user
406 has switched threads away from the thread that
407 forked. In that case, the resume command
408 issued is most likely not applicable to the
409 child, so just warn, and refuse to resume. */
411 Not resuming: switched threads before following fork child.\n"));
414 /* Reset breakpoints in the child as appropriate. */
415 follow_inferior_reset_breakpoints ();
418 switch_to_thread (parent
);
422 case TARGET_WAITKIND_SPURIOUS
:
423 /* Nothing to follow. */
426 internal_error (__FILE__
, __LINE__
,
427 "Unexpected pending_follow.kind %d\n",
428 tp
->pending_follow
.kind
);
432 return should_resume
;
436 follow_inferior_reset_breakpoints (void)
438 struct thread_info
*tp
= inferior_thread ();
440 /* Was there a step_resume breakpoint? (There was if the user
441 did a "next" at the fork() call.) If so, explicitly reset its
444 step_resumes are a form of bp that are made to be per-thread.
445 Since we created the step_resume bp when the parent process
446 was being debugged, and now are switching to the child process,
447 from the breakpoint package's viewpoint, that's a switch of
448 "threads". We must update the bp's notion of which thread
449 it is for, or it'll be ignored when it triggers. */
451 if (tp
->step_resume_breakpoint
)
452 breakpoint_re_set_thread (tp
->step_resume_breakpoint
);
454 /* Reinsert all breakpoints in the child. The user may have set
455 breakpoints after catching the fork, in which case those
456 were never set in the child, but only in the parent. This makes
457 sure the inserted breakpoints match the breakpoint list. */
459 breakpoint_re_set ();
460 insert_breakpoints ();
463 /* EXECD_PATHNAME is assumed to be non-NULL. */
466 follow_exec (ptid_t pid
, char *execd_pathname
)
468 struct target_ops
*tgt
;
469 struct thread_info
*th
= inferior_thread ();
471 /* This is an exec event that we actually wish to pay attention to.
472 Refresh our symbol table to the newly exec'd program, remove any
475 If there are breakpoints, they aren't really inserted now,
476 since the exec() transformed our inferior into a fresh set
479 We want to preserve symbolic breakpoints on the list, since
480 we have hopes that they can be reset after the new a.out's
481 symbol table is read.
483 However, any "raw" breakpoints must be removed from the list
484 (e.g., the solib bp's), since their address is probably invalid
487 And, we DON'T want to call delete_breakpoints() here, since
488 that may write the bp's "shadow contents" (the instruction
489 value that was overwritten witha TRAP instruction). Since
490 we now have a new a.out, those shadow contents aren't valid. */
491 update_breakpoints_after_exec ();
493 /* If there was one, it's gone now. We cannot truly step-to-next
494 statement through an exec(). */
495 th
->step_resume_breakpoint
= NULL
;
496 th
->step_range_start
= 0;
497 th
->step_range_end
= 0;
499 /* The target reports the exec event to the main thread, even if
500 some other thread does the exec, and even if the main thread was
501 already stopped --- if debugging in non-stop mode, it's possible
502 the user had the main thread held stopped in the previous image
503 --- release it now. This is the same behavior as step-over-exec
504 with scheduler-locking on in all-stop mode. */
505 th
->stop_requested
= 0;
507 /* What is this a.out's name? */
508 printf_unfiltered (_("Executing new program: %s\n"), execd_pathname
);
510 /* We've followed the inferior through an exec. Therefore, the
511 inferior has essentially been killed & reborn. */
513 gdb_flush (gdb_stdout
);
515 breakpoint_init_inferior (inf_execd
);
517 if (gdb_sysroot
&& *gdb_sysroot
)
519 char *name
= alloca (strlen (gdb_sysroot
)
520 + strlen (execd_pathname
)
522 strcpy (name
, gdb_sysroot
);
523 strcat (name
, execd_pathname
);
524 execd_pathname
= name
;
527 /* That a.out is now the one to use. */
528 exec_file_attach (execd_pathname
, 0);
530 /* Reset the shared library package. This ensures that we get a
531 shlib event when the child reaches "_start", at which point the
532 dld will have had a chance to initialize the child. */
533 /* Also, loading a symbol file below may trigger symbol lookups, and
534 we don't want those to be satisfied by the libraries of the
535 previous incarnation of this process. */
536 no_shared_libraries (NULL
, 0);
538 /* Load the main file's symbols. */
539 symbol_file_add_main (execd_pathname
, 0);
541 #ifdef SOLIB_CREATE_INFERIOR_HOOK
542 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
544 solib_create_inferior_hook ();
547 /* Reinsert all breakpoints. (Those which were symbolic have
548 been reset to the proper address in the new a.out, thanks
549 to symbol_file_command...) */
550 insert_breakpoints ();
552 /* The next resume of this inferior should bring it to the shlib
553 startup breakpoints. (If the user had also set bp's on
554 "main" from the old (parent) process, then they'll auto-
555 matically get reset there in the new process.) */
558 /* Non-zero if we just simulating a single-step. This is needed
559 because we cannot remove the breakpoints in the inferior process
560 until after the `wait' in `wait_for_inferior'. */
561 static int singlestep_breakpoints_inserted_p
= 0;
563 /* The thread we inserted single-step breakpoints for. */
564 static ptid_t singlestep_ptid
;
566 /* PC when we started this single-step. */
567 static CORE_ADDR singlestep_pc
;
569 /* If another thread hit the singlestep breakpoint, we save the original
570 thread here so that we can resume single-stepping it later. */
571 static ptid_t saved_singlestep_ptid
;
572 static int stepping_past_singlestep_breakpoint
;
574 /* If not equal to null_ptid, this means that after stepping over breakpoint
575 is finished, we need to switch to deferred_step_ptid, and step it.
577 The use case is when one thread has hit a breakpoint, and then the user
578 has switched to another thread and issued 'step'. We need to step over
579 breakpoint in the thread which hit the breakpoint, but then continue
580 stepping the thread user has selected. */
581 static ptid_t deferred_step_ptid
;
583 /* Displaced stepping. */
585 /* In non-stop debugging mode, we must take special care to manage
586 breakpoints properly; in particular, the traditional strategy for
587 stepping a thread past a breakpoint it has hit is unsuitable.
588 'Displaced stepping' is a tactic for stepping one thread past a
589 breakpoint it has hit while ensuring that other threads running
590 concurrently will hit the breakpoint as they should.
592 The traditional way to step a thread T off a breakpoint in a
593 multi-threaded program in all-stop mode is as follows:
595 a0) Initially, all threads are stopped, and breakpoints are not
597 a1) We single-step T, leaving breakpoints uninserted.
598 a2) We insert breakpoints, and resume all threads.
600 In non-stop debugging, however, this strategy is unsuitable: we
601 don't want to have to stop all threads in the system in order to
602 continue or step T past a breakpoint. Instead, we use displaced
605 n0) Initially, T is stopped, other threads are running, and
606 breakpoints are inserted.
607 n1) We copy the instruction "under" the breakpoint to a separate
608 location, outside the main code stream, making any adjustments
609 to the instruction, register, and memory state as directed by
611 n2) We single-step T over the instruction at its new location.
612 n3) We adjust the resulting register and memory state as directed
613 by T's architecture. This includes resetting T's PC to point
614 back into the main instruction stream.
617 This approach depends on the following gdbarch methods:
619 - gdbarch_max_insn_length and gdbarch_displaced_step_location
620 indicate where to copy the instruction, and how much space must
621 be reserved there. We use these in step n1.
623 - gdbarch_displaced_step_copy_insn copies a instruction to a new
624 address, and makes any necessary adjustments to the instruction,
625 register contents, and memory. We use this in step n1.
627 - gdbarch_displaced_step_fixup adjusts registers and memory after
628 we have successfuly single-stepped the instruction, to yield the
629 same effect the instruction would have had if we had executed it
630 at its original address. We use this in step n3.
632 - gdbarch_displaced_step_free_closure provides cleanup.
634 The gdbarch_displaced_step_copy_insn and
635 gdbarch_displaced_step_fixup functions must be written so that
636 copying an instruction with gdbarch_displaced_step_copy_insn,
637 single-stepping across the copied instruction, and then applying
638 gdbarch_displaced_insn_fixup should have the same effects on the
639 thread's memory and registers as stepping the instruction in place
640 would have. Exactly which responsibilities fall to the copy and
641 which fall to the fixup is up to the author of those functions.
643 See the comments in gdbarch.sh for details.
645 Note that displaced stepping and software single-step cannot
646 currently be used in combination, although with some care I think
647 they could be made to. Software single-step works by placing
648 breakpoints on all possible subsequent instructions; if the
649 displaced instruction is a PC-relative jump, those breakpoints
650 could fall in very strange places --- on pages that aren't
651 executable, or at addresses that are not proper instruction
652 boundaries. (We do generally let other threads run while we wait
653 to hit the software single-step breakpoint, and they might
654 encounter such a corrupted instruction.) One way to work around
655 this would be to have gdbarch_displaced_step_copy_insn fully
656 simulate the effect of PC-relative instructions (and return NULL)
657 on architectures that use software single-stepping.
659 In non-stop mode, we can have independent and simultaneous step
660 requests, so more than one thread may need to simultaneously step
661 over a breakpoint. The current implementation assumes there is
662 only one scratch space per process. In this case, we have to
663 serialize access to the scratch space. If thread A wants to step
664 over a breakpoint, but we are currently waiting for some other
665 thread to complete a displaced step, we leave thread A stopped and
666 place it in the displaced_step_request_queue. Whenever a displaced
667 step finishes, we pick the next thread in the queue and start a new
668 displaced step operation on it. See displaced_step_prepare and
669 displaced_step_fixup for details. */
671 /* If this is not null_ptid, this is the thread carrying out a
672 displaced single-step. This thread's state will require fixing up
673 once it has completed its step. */
674 static ptid_t displaced_step_ptid
;
676 struct displaced_step_request
679 struct displaced_step_request
*next
;
682 /* A queue of pending displaced stepping requests. */
683 struct displaced_step_request
*displaced_step_request_queue
;
685 /* The architecture the thread had when we stepped it. */
686 static struct gdbarch
*displaced_step_gdbarch
;
688 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
689 for post-step cleanup. */
690 static struct displaced_step_closure
*displaced_step_closure
;
692 /* The address of the original instruction, and the copy we made. */
693 static CORE_ADDR displaced_step_original
, displaced_step_copy
;
695 /* Saved contents of copy area. */
696 static gdb_byte
*displaced_step_saved_copy
;
698 /* Enum strings for "set|show displaced-stepping". */
700 static const char can_use_displaced_stepping_auto
[] = "auto";
701 static const char can_use_displaced_stepping_on
[] = "on";
702 static const char can_use_displaced_stepping_off
[] = "off";
703 static const char *can_use_displaced_stepping_enum
[] =
705 can_use_displaced_stepping_auto
,
706 can_use_displaced_stepping_on
,
707 can_use_displaced_stepping_off
,
711 /* If ON, and the architecture supports it, GDB will use displaced
712 stepping to step over breakpoints. If OFF, or if the architecture
713 doesn't support it, GDB will instead use the traditional
714 hold-and-step approach. If AUTO (which is the default), GDB will
715 decide which technique to use to step over breakpoints depending on
716 which of all-stop or non-stop mode is active --- displaced stepping
717 in non-stop mode; hold-and-step in all-stop mode. */
719 static const char *can_use_displaced_stepping
=
720 can_use_displaced_stepping_auto
;
723 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
724 struct cmd_list_element
*c
,
727 if (can_use_displaced_stepping
== can_use_displaced_stepping_auto
)
728 fprintf_filtered (file
, _("\
729 Debugger's willingness to use displaced stepping to step over \
730 breakpoints is %s (currently %s).\n"),
731 value
, non_stop
? "on" : "off");
733 fprintf_filtered (file
, _("\
734 Debugger's willingness to use displaced stepping to step over \
735 breakpoints is %s.\n"), value
);
738 /* Return non-zero if displaced stepping can/should be used to step
742 use_displaced_stepping (struct gdbarch
*gdbarch
)
744 return (((can_use_displaced_stepping
== can_use_displaced_stepping_auto
746 || can_use_displaced_stepping
== can_use_displaced_stepping_on
)
747 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
751 /* Clean out any stray displaced stepping state. */
753 displaced_step_clear (void)
755 /* Indicate that there is no cleanup pending. */
756 displaced_step_ptid
= null_ptid
;
758 if (displaced_step_closure
)
760 gdbarch_displaced_step_free_closure (displaced_step_gdbarch
,
761 displaced_step_closure
);
762 displaced_step_closure
= NULL
;
767 displaced_step_clear_cleanup (void *ignore
)
769 displaced_step_clear ();
772 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
774 displaced_step_dump_bytes (struct ui_file
*file
,
780 for (i
= 0; i
< len
; i
++)
781 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
782 fputs_unfiltered ("\n", file
);
785 /* Prepare to single-step, using displaced stepping.
787 Note that we cannot use displaced stepping when we have a signal to
788 deliver. If we have a signal to deliver and an instruction to step
789 over, then after the step, there will be no indication from the
790 target whether the thread entered a signal handler or ignored the
791 signal and stepped over the instruction successfully --- both cases
792 result in a simple SIGTRAP. In the first case we mustn't do a
793 fixup, and in the second case we must --- but we can't tell which.
794 Comments in the code for 'random signals' in handle_inferior_event
795 explain how we handle this case instead.
797 Returns 1 if preparing was successful -- this thread is going to be
798 stepped now; or 0 if displaced stepping this thread got queued. */
800 displaced_step_prepare (ptid_t ptid
)
802 struct cleanup
*old_cleanups
, *ignore_cleanups
;
803 struct regcache
*regcache
= get_thread_regcache (ptid
);
804 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
805 CORE_ADDR original
, copy
;
807 struct displaced_step_closure
*closure
;
809 /* We should never reach this function if the architecture does not
810 support displaced stepping. */
811 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
813 /* For the first cut, we're displaced stepping one thread at a
816 if (!ptid_equal (displaced_step_ptid
, null_ptid
))
818 /* Already waiting for a displaced step to finish. Defer this
819 request and place in queue. */
820 struct displaced_step_request
*req
, *new_req
;
823 fprintf_unfiltered (gdb_stdlog
,
824 "displaced: defering step of %s\n",
825 target_pid_to_str (ptid
));
827 new_req
= xmalloc (sizeof (*new_req
));
828 new_req
->ptid
= ptid
;
829 new_req
->next
= NULL
;
831 if (displaced_step_request_queue
)
833 for (req
= displaced_step_request_queue
;
840 displaced_step_request_queue
= new_req
;
847 fprintf_unfiltered (gdb_stdlog
,
848 "displaced: stepping %s now\n",
849 target_pid_to_str (ptid
));
852 displaced_step_clear ();
854 old_cleanups
= save_inferior_ptid ();
855 inferior_ptid
= ptid
;
857 original
= regcache_read_pc (regcache
);
859 copy
= gdbarch_displaced_step_location (gdbarch
);
860 len
= gdbarch_max_insn_length (gdbarch
);
862 /* Save the original contents of the copy area. */
863 displaced_step_saved_copy
= xmalloc (len
);
864 ignore_cleanups
= make_cleanup (free_current_contents
,
865 &displaced_step_saved_copy
);
866 read_memory (copy
, displaced_step_saved_copy
, len
);
869 fprintf_unfiltered (gdb_stdlog
, "displaced: saved 0x%s: ",
871 displaced_step_dump_bytes (gdb_stdlog
, displaced_step_saved_copy
, len
);
874 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
875 original
, copy
, regcache
);
877 /* We don't support the fully-simulated case at present. */
878 gdb_assert (closure
);
880 /* Save the information we need to fix things up if the step
882 displaced_step_ptid
= ptid
;
883 displaced_step_gdbarch
= gdbarch
;
884 displaced_step_closure
= closure
;
885 displaced_step_original
= original
;
886 displaced_step_copy
= copy
;
888 make_cleanup (displaced_step_clear_cleanup
, 0);
890 /* Resume execution at the copy. */
891 regcache_write_pc (regcache
, copy
);
893 discard_cleanups (ignore_cleanups
);
895 do_cleanups (old_cleanups
);
898 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to 0x%s\n",
905 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
, const gdb_byte
*myaddr
, int len
)
907 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
908 inferior_ptid
= ptid
;
909 write_memory (memaddr
, myaddr
, len
);
910 do_cleanups (ptid_cleanup
);
914 displaced_step_fixup (ptid_t event_ptid
, enum target_signal signal
)
916 struct cleanup
*old_cleanups
;
918 /* Was this event for the pid we displaced? */
919 if (ptid_equal (displaced_step_ptid
, null_ptid
)
920 || ! ptid_equal (displaced_step_ptid
, event_ptid
))
923 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, 0);
925 /* Restore the contents of the copy area. */
927 ULONGEST len
= gdbarch_max_insn_length (displaced_step_gdbarch
);
928 write_memory_ptid (displaced_step_ptid
, displaced_step_copy
,
929 displaced_step_saved_copy
, len
);
931 fprintf_unfiltered (gdb_stdlog
, "displaced: restored 0x%s\n",
932 paddr_nz (displaced_step_copy
));
935 /* Did the instruction complete successfully? */
936 if (signal
== TARGET_SIGNAL_TRAP
)
938 /* Fix up the resulting state. */
939 gdbarch_displaced_step_fixup (displaced_step_gdbarch
,
940 displaced_step_closure
,
941 displaced_step_original
,
943 get_thread_regcache (displaced_step_ptid
));
947 /* Since the instruction didn't complete, all we can do is
949 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
950 CORE_ADDR pc
= regcache_read_pc (regcache
);
951 pc
= displaced_step_original
+ (pc
- displaced_step_copy
);
952 regcache_write_pc (regcache
, pc
);
955 do_cleanups (old_cleanups
);
957 displaced_step_ptid
= null_ptid
;
959 /* Are there any pending displaced stepping requests? If so, run
961 while (displaced_step_request_queue
)
963 struct displaced_step_request
*head
;
967 head
= displaced_step_request_queue
;
969 displaced_step_request_queue
= head
->next
;
972 context_switch (ptid
);
974 actual_pc
= regcache_read_pc (get_thread_regcache (ptid
));
976 if (breakpoint_here_p (actual_pc
))
979 fprintf_unfiltered (gdb_stdlog
,
980 "displaced: stepping queued %s now\n",
981 target_pid_to_str (ptid
));
983 displaced_step_prepare (ptid
);
989 fprintf_unfiltered (gdb_stdlog
, "displaced: run 0x%s: ",
990 paddr_nz (actual_pc
));
991 read_memory (actual_pc
, buf
, sizeof (buf
));
992 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
995 target_resume (ptid
, 1, TARGET_SIGNAL_0
);
997 /* Done, we're stepping a thread. */
1003 struct thread_info
*tp
= inferior_thread ();
1005 /* The breakpoint we were sitting under has since been
1007 tp
->trap_expected
= 0;
1009 /* Go back to what we were trying to do. */
1010 step
= currently_stepping (tp
);
1012 if (debug_displaced
)
1013 fprintf_unfiltered (gdb_stdlog
, "breakpoint is gone %s: step(%d)\n",
1014 target_pid_to_str (tp
->ptid
), step
);
1016 target_resume (ptid
, step
, TARGET_SIGNAL_0
);
1017 tp
->stop_signal
= TARGET_SIGNAL_0
;
1019 /* This request was discarded. See if there's any other
1020 thread waiting for its turn. */
1025 /* Update global variables holding ptids to hold NEW_PTID if they were
1026 holding OLD_PTID. */
1028 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1030 struct displaced_step_request
*it
;
1032 if (ptid_equal (inferior_ptid
, old_ptid
))
1033 inferior_ptid
= new_ptid
;
1035 if (ptid_equal (singlestep_ptid
, old_ptid
))
1036 singlestep_ptid
= new_ptid
;
1038 if (ptid_equal (displaced_step_ptid
, old_ptid
))
1039 displaced_step_ptid
= new_ptid
;
1041 if (ptid_equal (deferred_step_ptid
, old_ptid
))
1042 deferred_step_ptid
= new_ptid
;
1044 for (it
= displaced_step_request_queue
; it
; it
= it
->next
)
1045 if (ptid_equal (it
->ptid
, old_ptid
))
1046 it
->ptid
= new_ptid
;
1052 /* Things to clean up if we QUIT out of resume (). */
1054 resume_cleanups (void *ignore
)
1059 static const char schedlock_off
[] = "off";
1060 static const char schedlock_on
[] = "on";
1061 static const char schedlock_step
[] = "step";
1062 static const char *scheduler_enums
[] = {
1068 static const char *scheduler_mode
= schedlock_off
;
1070 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1071 struct cmd_list_element
*c
, const char *value
)
1073 fprintf_filtered (file
, _("\
1074 Mode for locking scheduler during execution is \"%s\".\n"),
1079 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1081 if (!target_can_lock_scheduler
)
1083 scheduler_mode
= schedlock_off
;
1084 error (_("Target '%s' cannot support this command."), target_shortname
);
1088 /* True if execution commands resume all threads of all processes by
1089 default; otherwise, resume only threads of the current inferior
1091 int sched_multi
= 0;
1093 /* Try to setup for software single stepping over the specified location.
1094 Return 1 if target_resume() should use hardware single step.
1096 GDBARCH the current gdbarch.
1097 PC the location to step over. */
1100 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1104 if (gdbarch_software_single_step_p (gdbarch
)
1105 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1108 /* Do not pull these breakpoints until after a `wait' in
1109 `wait_for_inferior' */
1110 singlestep_breakpoints_inserted_p
= 1;
1111 singlestep_ptid
= inferior_ptid
;
1117 /* Resume the inferior, but allow a QUIT. This is useful if the user
1118 wants to interrupt some lengthy single-stepping operation
1119 (for child processes, the SIGINT goes to the inferior, and so
1120 we get a SIGINT random_signal, but for remote debugging and perhaps
1121 other targets, that's not true).
1123 STEP nonzero if we should step (zero to continue instead).
1124 SIG is the signal to give the inferior (zero for none). */
1126 resume (int step
, enum target_signal sig
)
1128 int should_resume
= 1;
1129 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
1130 struct regcache
*regcache
= get_current_regcache ();
1131 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1132 struct thread_info
*tp
= inferior_thread ();
1133 CORE_ADDR pc
= regcache_read_pc (regcache
);
1138 fprintf_unfiltered (gdb_stdlog
,
1139 "infrun: resume (step=%d, signal=%d), "
1140 "trap_expected=%d\n",
1141 step
, sig
, tp
->trap_expected
);
1143 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
1144 over an instruction that causes a page fault without triggering
1145 a hardware watchpoint. The kernel properly notices that it shouldn't
1146 stop, because the hardware watchpoint is not triggered, but it forgets
1147 the step request and continues the program normally.
1148 Work around the problem by removing hardware watchpoints if a step is
1149 requested, GDB will check for a hardware watchpoint trigger after the
1151 if (CANNOT_STEP_HW_WATCHPOINTS
&& step
)
1152 remove_hw_watchpoints ();
1155 /* Normally, by the time we reach `resume', the breakpoints are either
1156 removed or inserted, as appropriate. The exception is if we're sitting
1157 at a permanent breakpoint; we need to step over it, but permanent
1158 breakpoints can't be removed. So we have to test for it here. */
1159 if (breakpoint_here_p (pc
) == permanent_breakpoint_here
)
1161 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
1162 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
1165 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1166 how to step past a permanent breakpoint on this architecture. Try using\n\
1167 a command like `return' or `jump' to continue execution."));
1170 /* If enabled, step over breakpoints by executing a copy of the
1171 instruction at a different address.
1173 We can't use displaced stepping when we have a signal to deliver;
1174 the comments for displaced_step_prepare explain why. The
1175 comments in the handle_inferior event for dealing with 'random
1176 signals' explain what we do instead. */
1177 if (use_displaced_stepping (gdbarch
)
1178 && tp
->trap_expected
1179 && sig
== TARGET_SIGNAL_0
)
1181 if (!displaced_step_prepare (inferior_ptid
))
1183 /* Got placed in displaced stepping queue. Will be resumed
1184 later when all the currently queued displaced stepping
1185 requests finish. The thread is not executing at this point,
1186 and the call to set_executing will be made later. But we
1187 need to call set_running here, since from frontend point of view,
1188 the thread is running. */
1189 set_running (inferior_ptid
, 1);
1190 discard_cleanups (old_cleanups
);
1195 /* Do we need to do it the hard way, w/temp breakpoints? */
1197 step
= maybe_software_singlestep (gdbarch
, pc
);
1203 /* If STEP is set, it's a request to use hardware stepping
1204 facilities. But in that case, we should never
1205 use singlestep breakpoint. */
1206 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1208 /* Decide the set of threads to ask the target to resume. Start
1209 by assuming everything will be resumed, than narrow the set
1210 by applying increasingly restricting conditions. */
1212 /* By default, resume all threads of all processes. */
1213 resume_ptid
= RESUME_ALL
;
1215 /* Maybe resume only all threads of the current process. */
1216 if (!sched_multi
&& target_supports_multi_process ())
1218 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1221 /* Maybe resume a single thread after all. */
1222 if (singlestep_breakpoints_inserted_p
1223 && stepping_past_singlestep_breakpoint
)
1225 /* The situation here is as follows. In thread T1 we wanted to
1226 single-step. Lacking hardware single-stepping we've
1227 set breakpoint at the PC of the next instruction -- call it
1228 P. After resuming, we've hit that breakpoint in thread T2.
1229 Now we've removed original breakpoint, inserted breakpoint
1230 at P+1, and try to step to advance T2 past breakpoint.
1231 We need to step only T2, as if T1 is allowed to freely run,
1232 it can run past P, and if other threads are allowed to run,
1233 they can hit breakpoint at P+1, and nested hits of single-step
1234 breakpoints is not something we'd want -- that's complicated
1235 to support, and has no value. */
1236 resume_ptid
= inferior_ptid
;
1238 else if ((step
|| singlestep_breakpoints_inserted_p
)
1239 && tp
->trap_expected
)
1241 /* We're allowing a thread to run past a breakpoint it has
1242 hit, by single-stepping the thread with the breakpoint
1243 removed. In which case, we need to single-step only this
1244 thread, and keep others stopped, as they can miss this
1245 breakpoint if allowed to run.
1247 The current code actually removes all breakpoints when
1248 doing this, not just the one being stepped over, so if we
1249 let other threads run, we can actually miss any
1250 breakpoint, not just the one at PC. */
1251 resume_ptid
= inferior_ptid
;
1255 /* With non-stop mode on, threads are always handled
1257 resume_ptid
= inferior_ptid
;
1259 else if ((scheduler_mode
== schedlock_on
)
1260 || (scheduler_mode
== schedlock_step
1261 && (step
|| singlestep_breakpoints_inserted_p
)))
1263 /* User-settable 'scheduler' mode requires solo thread resume. */
1264 resume_ptid
= inferior_ptid
;
1267 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1269 /* Most targets can step a breakpoint instruction, thus
1270 executing it normally. But if this one cannot, just
1271 continue and we will hit it anyway. */
1272 if (step
&& breakpoint_inserted_here_p (pc
))
1277 && use_displaced_stepping (gdbarch
)
1278 && tp
->trap_expected
)
1280 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1281 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1284 fprintf_unfiltered (gdb_stdlog
, "displaced: run 0x%s: ",
1285 paddr_nz (actual_pc
));
1286 read_memory (actual_pc
, buf
, sizeof (buf
));
1287 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1290 /* Install inferior's terminal modes. */
1291 target_terminal_inferior ();
1293 /* Avoid confusing the next resume, if the next stop/resume
1294 happens to apply to another thread. */
1295 tp
->stop_signal
= TARGET_SIGNAL_0
;
1297 target_resume (resume_ptid
, step
, sig
);
1300 discard_cleanups (old_cleanups
);
1305 /* Clear out all variables saying what to do when inferior is continued.
1306 First do this, then set the ones you want, then call `proceed'. */
1309 clear_proceed_status_thread (struct thread_info
*tp
)
1312 fprintf_unfiltered (gdb_stdlog
,
1313 "infrun: clear_proceed_status_thread (%s)\n",
1314 target_pid_to_str (tp
->ptid
));
1316 tp
->trap_expected
= 0;
1317 tp
->step_range_start
= 0;
1318 tp
->step_range_end
= 0;
1319 tp
->step_frame_id
= null_frame_id
;
1320 tp
->step_stack_frame_id
= null_frame_id
;
1321 tp
->step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1322 tp
->stop_requested
= 0;
1326 tp
->proceed_to_finish
= 0;
1328 /* Discard any remaining commands or status from previous stop. */
1329 bpstat_clear (&tp
->stop_bpstat
);
1333 clear_proceed_status_callback (struct thread_info
*tp
, void *data
)
1335 if (is_exited (tp
->ptid
))
1338 clear_proceed_status_thread (tp
);
1343 clear_proceed_status (void)
1345 if (!ptid_equal (inferior_ptid
, null_ptid
))
1347 struct inferior
*inferior
;
1351 /* If in non-stop mode, only delete the per-thread status
1352 of the current thread. */
1353 clear_proceed_status_thread (inferior_thread ());
1357 /* In all-stop mode, delete the per-thread status of
1359 iterate_over_threads (clear_proceed_status_callback
, NULL
);
1362 inferior
= current_inferior ();
1363 inferior
->stop_soon
= NO_STOP_QUIETLY
;
1366 stop_after_trap
= 0;
1368 observer_notify_about_to_proceed ();
1372 regcache_xfree (stop_registers
);
1373 stop_registers
= NULL
;
1377 /* Check the current thread against the thread that reported the most recent
1378 event. If a step-over is required return TRUE and set the current thread
1379 to the old thread. Otherwise return FALSE.
1381 This should be suitable for any targets that support threads. */
1384 prepare_to_proceed (int step
)
1387 struct target_waitstatus wait_status
;
1388 int schedlock_enabled
;
1390 /* With non-stop mode on, threads are always handled individually. */
1391 gdb_assert (! non_stop
);
1393 /* Get the last target status returned by target_wait(). */
1394 get_last_target_status (&wait_ptid
, &wait_status
);
1396 /* Make sure we were stopped at a breakpoint. */
1397 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
1398 || wait_status
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1403 schedlock_enabled
= (scheduler_mode
== schedlock_on
1404 || (scheduler_mode
== schedlock_step
1407 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
1408 if (schedlock_enabled
)
1411 /* Don't switch over if we're about to resume some other process
1412 other than WAIT_PTID's, and schedule-multiple is off. */
1414 && ptid_get_pid (wait_ptid
) != ptid_get_pid (inferior_ptid
))
1417 /* Switched over from WAIT_PID. */
1418 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
1419 && !ptid_equal (inferior_ptid
, wait_ptid
))
1421 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
1423 if (breakpoint_here_p (regcache_read_pc (regcache
)))
1425 /* If stepping, remember current thread to switch back to. */
1427 deferred_step_ptid
= inferior_ptid
;
1429 /* Switch back to WAIT_PID thread. */
1430 switch_to_thread (wait_ptid
);
1432 /* We return 1 to indicate that there is a breakpoint here,
1433 so we need to step over it before continuing to avoid
1434 hitting it straight away. */
1442 /* Basic routine for continuing the program in various fashions.
1444 ADDR is the address to resume at, or -1 for resume where stopped.
1445 SIGGNAL is the signal to give it, or 0 for none,
1446 or -1 for act according to how it stopped.
1447 STEP is nonzero if should trap after one instruction.
1448 -1 means return after that and print nothing.
1449 You should probably set various step_... variables
1450 before calling here, if you are stepping.
1452 You should call clear_proceed_status before calling proceed. */
1455 proceed (CORE_ADDR addr
, enum target_signal siggnal
, int step
)
1457 struct regcache
*regcache
;
1458 struct gdbarch
*gdbarch
;
1459 struct thread_info
*tp
;
1463 /* If we're stopped at a fork/vfork, follow the branch set by the
1464 "set follow-fork-mode" command; otherwise, we'll just proceed
1465 resuming the current thread. */
1466 if (!follow_fork ())
1468 /* The target for some reason decided not to resume. */
1473 regcache
= get_current_regcache ();
1474 gdbarch
= get_regcache_arch (regcache
);
1475 pc
= regcache_read_pc (regcache
);
1478 step_start_function
= find_pc_function (pc
);
1480 stop_after_trap
= 1;
1482 if (addr
== (CORE_ADDR
) -1)
1484 if (pc
== stop_pc
&& breakpoint_here_p (pc
)
1485 && execution_direction
!= EXEC_REVERSE
)
1486 /* There is a breakpoint at the address we will resume at,
1487 step one instruction before inserting breakpoints so that
1488 we do not stop right away (and report a second hit at this
1491 Note, we don't do this in reverse, because we won't
1492 actually be executing the breakpoint insn anyway.
1493 We'll be (un-)executing the previous instruction. */
1496 else if (gdbarch_single_step_through_delay_p (gdbarch
)
1497 && gdbarch_single_step_through_delay (gdbarch
,
1498 get_current_frame ()))
1499 /* We stepped onto an instruction that needs to be stepped
1500 again before re-inserting the breakpoint, do so. */
1505 regcache_write_pc (regcache
, addr
);
1509 fprintf_unfiltered (gdb_stdlog
,
1510 "infrun: proceed (addr=0x%s, signal=%d, step=%d)\n",
1511 paddr_nz (addr
), siggnal
, step
);
1514 /* In non-stop, each thread is handled individually. The context
1515 must already be set to the right thread here. */
1519 /* In a multi-threaded task we may select another thread and
1520 then continue or step.
1522 But if the old thread was stopped at a breakpoint, it will
1523 immediately cause another breakpoint stop without any
1524 execution (i.e. it will report a breakpoint hit incorrectly).
1525 So we must step over it first.
1527 prepare_to_proceed checks the current thread against the
1528 thread that reported the most recent event. If a step-over
1529 is required it returns TRUE and sets the current thread to
1531 if (prepare_to_proceed (step
))
1535 /* prepare_to_proceed may change the current thread. */
1536 tp
= inferior_thread ();
1540 tp
->trap_expected
= 1;
1541 /* If displaced stepping is enabled, we can step over the
1542 breakpoint without hitting it, so leave all breakpoints
1543 inserted. Otherwise we need to disable all breakpoints, step
1544 one instruction, and then re-add them when that step is
1546 if (!use_displaced_stepping (gdbarch
))
1547 remove_breakpoints ();
1550 /* We can insert breakpoints if we're not trying to step over one,
1551 or if we are stepping over one but we're using displaced stepping
1553 if (! tp
->trap_expected
|| use_displaced_stepping (gdbarch
))
1554 insert_breakpoints ();
1558 /* Pass the last stop signal to the thread we're resuming,
1559 irrespective of whether the current thread is the thread that
1560 got the last event or not. This was historically GDB's
1561 behaviour before keeping a stop_signal per thread. */
1563 struct thread_info
*last_thread
;
1565 struct target_waitstatus last_status
;
1567 get_last_target_status (&last_ptid
, &last_status
);
1568 if (!ptid_equal (inferior_ptid
, last_ptid
)
1569 && !ptid_equal (last_ptid
, null_ptid
)
1570 && !ptid_equal (last_ptid
, minus_one_ptid
))
1572 last_thread
= find_thread_ptid (last_ptid
);
1575 tp
->stop_signal
= last_thread
->stop_signal
;
1576 last_thread
->stop_signal
= TARGET_SIGNAL_0
;
1581 if (siggnal
!= TARGET_SIGNAL_DEFAULT
)
1582 tp
->stop_signal
= siggnal
;
1583 /* If this signal should not be seen by program,
1584 give it zero. Used for debugging signals. */
1585 else if (!signal_program
[tp
->stop_signal
])
1586 tp
->stop_signal
= TARGET_SIGNAL_0
;
1588 annotate_starting ();
1590 /* Make sure that output from GDB appears before output from the
1592 gdb_flush (gdb_stdout
);
1594 /* Refresh prev_pc value just prior to resuming. This used to be
1595 done in stop_stepping, however, setting prev_pc there did not handle
1596 scenarios such as inferior function calls or returning from
1597 a function via the return command. In those cases, the prev_pc
1598 value was not set properly for subsequent commands. The prev_pc value
1599 is used to initialize the starting line number in the ecs. With an
1600 invalid value, the gdb next command ends up stopping at the position
1601 represented by the next line table entry past our start position.
1602 On platforms that generate one line table entry per line, this
1603 is not a problem. However, on the ia64, the compiler generates
1604 extraneous line table entries that do not increase the line number.
1605 When we issue the gdb next command on the ia64 after an inferior call
1606 or a return command, we often end up a few instructions forward, still
1607 within the original line we started.
1609 An attempt was made to have init_execution_control_state () refresh
1610 the prev_pc value before calculating the line number. This approach
1611 did not work because on platforms that use ptrace, the pc register
1612 cannot be read unless the inferior is stopped. At that point, we
1613 are not guaranteed the inferior is stopped and so the regcache_read_pc ()
1614 call can fail. Setting the prev_pc value here ensures the value is
1615 updated correctly when the inferior is stopped. */
1616 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
1618 /* Fill in with reasonable starting values. */
1619 init_thread_stepping_state (tp
);
1621 /* Reset to normal state. */
1622 init_infwait_state ();
1624 /* Resume inferior. */
1625 resume (oneproc
|| step
|| bpstat_should_step (), tp
->stop_signal
);
1627 /* Wait for it to stop (if not standalone)
1628 and in any case decode why it stopped, and act accordingly. */
1629 /* Do this only if we are not using the event loop, or if the target
1630 does not support asynchronous execution. */
1631 if (!target_can_async_p ())
1633 wait_for_inferior (0);
1639 /* Start remote-debugging of a machine over a serial link. */
1642 start_remote (int from_tty
)
1644 struct inferior
*inferior
;
1645 init_wait_for_inferior ();
1647 inferior
= current_inferior ();
1648 inferior
->stop_soon
= STOP_QUIETLY_REMOTE
;
1650 /* Always go on waiting for the target, regardless of the mode. */
1651 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1652 indicate to wait_for_inferior that a target should timeout if
1653 nothing is returned (instead of just blocking). Because of this,
1654 targets expecting an immediate response need to, internally, set
1655 things up so that the target_wait() is forced to eventually
1657 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1658 differentiate to its caller what the state of the target is after
1659 the initial open has been performed. Here we're assuming that
1660 the target has stopped. It should be possible to eventually have
1661 target_open() return to the caller an indication that the target
1662 is currently running and GDB state should be set to the same as
1663 for an async run. */
1664 wait_for_inferior (0);
1666 /* Now that the inferior has stopped, do any bookkeeping like
1667 loading shared libraries. We want to do this before normal_stop,
1668 so that the displayed frame is up to date. */
1669 post_create_inferior (¤t_target
, from_tty
);
1674 /* Initialize static vars when a new inferior begins. */
1677 init_wait_for_inferior (void)
1679 /* These are meaningless until the first time through wait_for_inferior. */
1681 breakpoint_init_inferior (inf_starting
);
1683 clear_proceed_status ();
1685 stepping_past_singlestep_breakpoint
= 0;
1686 deferred_step_ptid
= null_ptid
;
1688 target_last_wait_ptid
= minus_one_ptid
;
1690 previous_inferior_ptid
= null_ptid
;
1691 init_infwait_state ();
1693 displaced_step_clear ();
1695 /* Discard any skipped inlined frames. */
1696 clear_inline_frame_state (minus_one_ptid
);
1700 /* This enum encodes possible reasons for doing a target_wait, so that
1701 wfi can call target_wait in one place. (Ultimately the call will be
1702 moved out of the infinite loop entirely.) */
1706 infwait_normal_state
,
1707 infwait_thread_hop_state
,
1708 infwait_step_watch_state
,
1709 infwait_nonstep_watch_state
1712 /* Why did the inferior stop? Used to print the appropriate messages
1713 to the interface from within handle_inferior_event(). */
1714 enum inferior_stop_reason
1716 /* Step, next, nexti, stepi finished. */
1718 /* Inferior terminated by signal. */
1720 /* Inferior exited. */
1722 /* Inferior received signal, and user asked to be notified. */
1724 /* Reverse execution -- target ran out of history info. */
1728 /* The PTID we'll do a target_wait on.*/
1731 /* Current inferior wait state. */
1732 enum infwait_states infwait_state
;
1734 /* Data to be passed around while handling an event. This data is
1735 discarded between events. */
1736 struct execution_control_state
1739 /* The thread that got the event, if this was a thread event; NULL
1741 struct thread_info
*event_thread
;
1743 struct target_waitstatus ws
;
1745 CORE_ADDR stop_func_start
;
1746 CORE_ADDR stop_func_end
;
1747 char *stop_func_name
;
1748 int new_thread_event
;
1752 static void init_execution_control_state (struct execution_control_state
*ecs
);
1754 void handle_inferior_event (struct execution_control_state
*ecs
);
1756 static void handle_step_into_function (struct gdbarch
*gdbarch
,
1757 struct execution_control_state
*ecs
);
1758 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
1759 struct execution_control_state
*ecs
);
1760 static void insert_step_resume_breakpoint_at_frame (struct frame_info
*step_frame
);
1761 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
1762 static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
1763 struct frame_id sr_id
);
1764 static void insert_longjmp_resume_breakpoint (CORE_ADDR
);
1766 static void stop_stepping (struct execution_control_state
*ecs
);
1767 static void prepare_to_wait (struct execution_control_state
*ecs
);
1768 static void keep_going (struct execution_control_state
*ecs
);
1769 static void print_stop_reason (enum inferior_stop_reason stop_reason
,
1772 /* Callback for iterate over threads. If the thread is stopped, but
1773 the user/frontend doesn't know about that yet, go through
1774 normal_stop, as if the thread had just stopped now. ARG points at
1775 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
1776 ptid_is_pid(PTID) is true, applies to all threads of the process
1777 pointed at by PTID. Otherwise, apply only to the thread pointed by
1781 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
1783 ptid_t ptid
= * (ptid_t
*) arg
;
1785 if ((ptid_equal (info
->ptid
, ptid
)
1786 || ptid_equal (minus_one_ptid
, ptid
)
1787 || (ptid_is_pid (ptid
)
1788 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
1789 && is_running (info
->ptid
)
1790 && !is_executing (info
->ptid
))
1792 struct cleanup
*old_chain
;
1793 struct execution_control_state ecss
;
1794 struct execution_control_state
*ecs
= &ecss
;
1796 memset (ecs
, 0, sizeof (*ecs
));
1798 old_chain
= make_cleanup_restore_current_thread ();
1800 switch_to_thread (info
->ptid
);
1802 /* Go through handle_inferior_event/normal_stop, so we always
1803 have consistent output as if the stop event had been
1805 ecs
->ptid
= info
->ptid
;
1806 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
1807 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
1808 ecs
->ws
.value
.sig
= TARGET_SIGNAL_0
;
1810 handle_inferior_event (ecs
);
1812 if (!ecs
->wait_some_more
)
1814 struct thread_info
*tp
;
1818 /* Finish off the continuations. The continations
1819 themselves are responsible for realising the thread
1820 didn't finish what it was supposed to do. */
1821 tp
= inferior_thread ();
1822 do_all_intermediate_continuations_thread (tp
);
1823 do_all_continuations_thread (tp
);
1826 do_cleanups (old_chain
);
1832 /* This function is attached as a "thread_stop_requested" observer.
1833 Cleanup local state that assumed the PTID was to be resumed, and
1834 report the stop to the frontend. */
1837 infrun_thread_stop_requested (ptid_t ptid
)
1839 struct displaced_step_request
*it
, *next
, *prev
= NULL
;
1841 /* PTID was requested to stop. Remove it from the displaced
1842 stepping queue, so we don't try to resume it automatically. */
1843 for (it
= displaced_step_request_queue
; it
; it
= next
)
1847 if (ptid_equal (it
->ptid
, ptid
)
1848 || ptid_equal (minus_one_ptid
, ptid
)
1849 || (ptid_is_pid (ptid
)
1850 && ptid_get_pid (ptid
) == ptid_get_pid (it
->ptid
)))
1852 if (displaced_step_request_queue
== it
)
1853 displaced_step_request_queue
= it
->next
;
1855 prev
->next
= it
->next
;
1863 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
1867 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
1869 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
1870 nullify_last_target_wait_ptid ();
1873 /* Callback for iterate_over_threads. */
1876 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
1878 if (is_exited (info
->ptid
))
1881 delete_step_resume_breakpoint (info
);
1885 /* In all-stop, delete the step resume breakpoint of any thread that
1886 had one. In non-stop, delete the step resume breakpoint of the
1887 thread that just stopped. */
1890 delete_step_thread_step_resume_breakpoint (void)
1892 if (!target_has_execution
1893 || ptid_equal (inferior_ptid
, null_ptid
))
1894 /* If the inferior has exited, we have already deleted the step
1895 resume breakpoints out of GDB's lists. */
1900 /* If in non-stop mode, only delete the step-resume or
1901 longjmp-resume breakpoint of the thread that just stopped
1903 struct thread_info
*tp
= inferior_thread ();
1904 delete_step_resume_breakpoint (tp
);
1907 /* In all-stop mode, delete all step-resume and longjmp-resume
1908 breakpoints of any thread that had them. */
1909 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
1912 /* A cleanup wrapper. */
1915 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
1917 delete_step_thread_step_resume_breakpoint ();
1920 /* Pretty print the results of target_wait, for debugging purposes. */
1923 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
1924 const struct target_waitstatus
*ws
)
1926 char *status_string
= target_waitstatus_to_string (ws
);
1927 struct ui_file
*tmp_stream
= mem_fileopen ();
1931 /* The text is split over several lines because it was getting too long.
1932 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
1933 output as a unit; we want only one timestamp printed if debug_timestamp
1936 fprintf_unfiltered (tmp_stream
,
1937 "infrun: target_wait (%d", PIDGET (waiton_ptid
));
1938 if (PIDGET (waiton_ptid
) != -1)
1939 fprintf_unfiltered (tmp_stream
,
1940 " [%s]", target_pid_to_str (waiton_ptid
));
1941 fprintf_unfiltered (tmp_stream
, ", status) =\n");
1942 fprintf_unfiltered (tmp_stream
,
1943 "infrun: %d [%s],\n",
1944 PIDGET (result_ptid
), target_pid_to_str (result_ptid
));
1945 fprintf_unfiltered (tmp_stream
,
1949 text
= ui_file_xstrdup (tmp_stream
, &len
);
1951 /* This uses %s in part to handle %'s in the text, but also to avoid
1952 a gcc error: the format attribute requires a string literal. */
1953 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
1955 xfree (status_string
);
1957 ui_file_delete (tmp_stream
);
1960 /* Wait for control to return from inferior to debugger.
1962 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
1963 as if they were SIGTRAP signals. This can be useful during
1964 the startup sequence on some targets such as HP/UX, where
1965 we receive an EXEC event instead of the expected SIGTRAP.
1967 If inferior gets a signal, we may decide to start it up again
1968 instead of returning. That is why there is a loop in this function.
1969 When this function actually returns it means the inferior
1970 should be left stopped and GDB should read more commands. */
1973 wait_for_inferior (int treat_exec_as_sigtrap
)
1975 struct cleanup
*old_cleanups
;
1976 struct execution_control_state ecss
;
1977 struct execution_control_state
*ecs
;
1981 (gdb_stdlog
, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
1982 treat_exec_as_sigtrap
);
1985 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
1988 memset (ecs
, 0, sizeof (*ecs
));
1990 overlay_cache_invalid
= 1;
1992 /* We'll update this if & when we switch to a new thread. */
1993 previous_inferior_ptid
= inferior_ptid
;
1995 /* We have to invalidate the registers BEFORE calling target_wait
1996 because they can be loaded from the target while in target_wait.
1997 This makes remote debugging a bit more efficient for those
1998 targets that provide critical registers as part of their normal
1999 status mechanism. */
2001 registers_changed ();
2005 struct cleanup
*old_chain
;
2007 if (deprecated_target_wait_hook
)
2008 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2010 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2013 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2015 if (treat_exec_as_sigtrap
&& ecs
->ws
.kind
== TARGET_WAITKIND_EXECD
)
2017 xfree (ecs
->ws
.value
.execd_pathname
);
2018 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2019 ecs
->ws
.value
.sig
= TARGET_SIGNAL_TRAP
;
2022 /* If an error happens while handling the event, propagate GDB's
2023 knowledge of the executing state to the frontend/user running
2025 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2027 /* Now figure out what to do with the result of the result. */
2028 handle_inferior_event (ecs
);
2030 /* No error, don't finish the state yet. */
2031 discard_cleanups (old_chain
);
2033 if (!ecs
->wait_some_more
)
2037 do_cleanups (old_cleanups
);
2040 /* Asynchronous version of wait_for_inferior. It is called by the
2041 event loop whenever a change of state is detected on the file
2042 descriptor corresponding to the target. It can be called more than
2043 once to complete a single execution command. In such cases we need
2044 to keep the state in a global variable ECSS. If it is the last time
2045 that this function is called for a single execution command, then
2046 report to the user that the inferior has stopped, and do the
2047 necessary cleanups. */
2050 fetch_inferior_event (void *client_data
)
2052 struct execution_control_state ecss
;
2053 struct execution_control_state
*ecs
= &ecss
;
2054 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2055 struct cleanup
*ts_old_chain
;
2056 int was_sync
= sync_execution
;
2058 memset (ecs
, 0, sizeof (*ecs
));
2060 overlay_cache_invalid
= 1;
2062 /* We can only rely on wait_for_more being correct before handling
2063 the event in all-stop, but previous_inferior_ptid isn't used in
2065 if (!ecs
->wait_some_more
)
2066 /* We'll update this if & when we switch to a new thread. */
2067 previous_inferior_ptid
= inferior_ptid
;
2070 /* In non-stop mode, the user/frontend should not notice a thread
2071 switch due to internal events. Make sure we reverse to the
2072 user selected thread and frame after handling the event and
2073 running any breakpoint commands. */
2074 make_cleanup_restore_current_thread ();
2076 /* We have to invalidate the registers BEFORE calling target_wait
2077 because they can be loaded from the target while in target_wait.
2078 This makes remote debugging a bit more efficient for those
2079 targets that provide critical registers as part of their normal
2080 status mechanism. */
2082 registers_changed ();
2084 if (deprecated_target_wait_hook
)
2086 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2088 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2091 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2094 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
2095 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2096 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2097 /* In non-stop mode, each thread is handled individually. Switch
2098 early, so the global state is set correctly for this
2100 context_switch (ecs
->ptid
);
2102 /* If an error happens while handling the event, propagate GDB's
2103 knowledge of the executing state to the frontend/user running
2106 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2108 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2110 /* Now figure out what to do with the result of the result. */
2111 handle_inferior_event (ecs
);
2113 if (!ecs
->wait_some_more
)
2115 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2117 delete_step_thread_step_resume_breakpoint ();
2119 /* We may not find an inferior if this was a process exit. */
2120 if (inf
== NULL
|| inf
->stop_soon
== NO_STOP_QUIETLY
)
2123 if (target_has_execution
2124 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2125 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2126 && ecs
->event_thread
->step_multi
2127 && ecs
->event_thread
->stop_step
)
2128 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2130 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2133 /* No error, don't finish the thread states yet. */
2134 discard_cleanups (ts_old_chain
);
2136 /* Revert thread and frame. */
2137 do_cleanups (old_chain
);
2139 /* If the inferior was in sync execution mode, and now isn't,
2140 restore the prompt. */
2141 if (was_sync
&& !sync_execution
)
2142 display_gdb_prompt (0);
2145 /* Record the frame and location we're currently stepping through. */
2147 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2149 struct thread_info
*tp
= inferior_thread ();
2151 tp
->step_frame_id
= get_frame_id (frame
);
2152 tp
->step_stack_frame_id
= get_stack_frame_id (frame
);
2154 tp
->current_symtab
= sal
.symtab
;
2155 tp
->current_line
= sal
.line
;
2158 /* Prepare an execution control state for looping through a
2159 wait_for_inferior-type loop. */
2162 init_execution_control_state (struct execution_control_state
*ecs
)
2164 ecs
->random_signal
= 0;
2167 /* Clear context switchable stepping state. */
2170 init_thread_stepping_state (struct thread_info
*tss
)
2172 tss
->stepping_over_breakpoint
= 0;
2173 tss
->step_after_step_resume_breakpoint
= 0;
2174 tss
->stepping_through_solib_after_catch
= 0;
2175 tss
->stepping_through_solib_catchpoints
= NULL
;
2178 /* Return the cached copy of the last pid/waitstatus returned by
2179 target_wait()/deprecated_target_wait_hook(). The data is actually
2180 cached by handle_inferior_event(), which gets called immediately
2181 after target_wait()/deprecated_target_wait_hook(). */
2184 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2186 *ptidp
= target_last_wait_ptid
;
2187 *status
= target_last_waitstatus
;
2191 nullify_last_target_wait_ptid (void)
2193 target_last_wait_ptid
= minus_one_ptid
;
2196 /* Switch thread contexts. */
2199 context_switch (ptid_t ptid
)
2203 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2204 target_pid_to_str (inferior_ptid
));
2205 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2206 target_pid_to_str (ptid
));
2209 switch_to_thread (ptid
);
2213 adjust_pc_after_break (struct execution_control_state
*ecs
)
2215 struct regcache
*regcache
;
2216 struct gdbarch
*gdbarch
;
2217 CORE_ADDR breakpoint_pc
;
2219 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2220 we aren't, just return.
2222 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2223 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2224 implemented by software breakpoints should be handled through the normal
2227 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2228 different signals (SIGILL or SIGEMT for instance), but it is less
2229 clear where the PC is pointing afterwards. It may not match
2230 gdbarch_decr_pc_after_break. I don't know any specific target that
2231 generates these signals at breakpoints (the code has been in GDB since at
2232 least 1992) so I can not guess how to handle them here.
2234 In earlier versions of GDB, a target with
2235 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2236 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2237 target with both of these set in GDB history, and it seems unlikely to be
2238 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2240 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2243 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
2246 /* In reverse execution, when a breakpoint is hit, the instruction
2247 under it has already been de-executed. The reported PC always
2248 points at the breakpoint address, so adjusting it further would
2249 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2252 B1 0x08000000 : INSN1
2253 B2 0x08000001 : INSN2
2255 PC -> 0x08000003 : INSN4
2257 Say you're stopped at 0x08000003 as above. Reverse continuing
2258 from that point should hit B2 as below. Reading the PC when the
2259 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2260 been de-executed already.
2262 B1 0x08000000 : INSN1
2263 B2 PC -> 0x08000001 : INSN2
2267 We can't apply the same logic as for forward execution, because
2268 we would wrongly adjust the PC to 0x08000000, since there's a
2269 breakpoint at PC - 1. We'd then report a hit on B1, although
2270 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2272 if (execution_direction
== EXEC_REVERSE
)
2275 /* If this target does not decrement the PC after breakpoints, then
2276 we have nothing to do. */
2277 regcache
= get_thread_regcache (ecs
->ptid
);
2278 gdbarch
= get_regcache_arch (regcache
);
2279 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
2282 /* Find the location where (if we've hit a breakpoint) the
2283 breakpoint would be. */
2284 breakpoint_pc
= regcache_read_pc (regcache
)
2285 - gdbarch_decr_pc_after_break (gdbarch
);
2287 /* Check whether there actually is a software breakpoint inserted at
2290 If in non-stop mode, a race condition is possible where we've
2291 removed a breakpoint, but stop events for that breakpoint were
2292 already queued and arrive later. To suppress those spurious
2293 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
2294 and retire them after a number of stop events are reported. */
2295 if (software_breakpoint_inserted_here_p (breakpoint_pc
)
2296 || (non_stop
&& moribund_breakpoint_here_p (breakpoint_pc
)))
2298 struct cleanup
*old_cleanups
= NULL
;
2300 old_cleanups
= record_gdb_operation_disable_set ();
2302 /* When using hardware single-step, a SIGTRAP is reported for both
2303 a completed single-step and a software breakpoint. Need to
2304 differentiate between the two, as the latter needs adjusting
2305 but the former does not.
2307 The SIGTRAP can be due to a completed hardware single-step only if
2308 - we didn't insert software single-step breakpoints
2309 - the thread to be examined is still the current thread
2310 - this thread is currently being stepped
2312 If any of these events did not occur, we must have stopped due
2313 to hitting a software breakpoint, and have to back up to the
2316 As a special case, we could have hardware single-stepped a
2317 software breakpoint. In this case (prev_pc == breakpoint_pc),
2318 we also need to back up to the breakpoint address. */
2320 if (singlestep_breakpoints_inserted_p
2321 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
2322 || !currently_stepping (ecs
->event_thread
)
2323 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
2324 regcache_write_pc (regcache
, breakpoint_pc
);
2327 do_cleanups (old_cleanups
);
2332 init_infwait_state (void)
2334 waiton_ptid
= pid_to_ptid (-1);
2335 infwait_state
= infwait_normal_state
;
2339 error_is_running (void)
2342 Cannot execute this command while the selected thread is running."));
2346 ensure_not_running (void)
2348 if (is_running (inferior_ptid
))
2349 error_is_running ();
2353 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
2355 for (frame
= get_prev_frame (frame
);
2357 frame
= get_prev_frame (frame
))
2359 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
2361 if (get_frame_type (frame
) != INLINE_FRAME
)
2368 /* Given an execution control state that has been freshly filled in
2369 by an event from the inferior, figure out what it means and take
2370 appropriate action. */
2373 handle_inferior_event (struct execution_control_state
*ecs
)
2375 struct frame_info
*frame
;
2376 struct gdbarch
*gdbarch
;
2377 int sw_single_step_trap_p
= 0;
2378 int stopped_by_watchpoint
;
2379 int stepped_after_stopped_by_watchpoint
= 0;
2380 struct symtab_and_line stop_pc_sal
;
2381 enum stop_kind stop_soon
;
2383 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2384 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2385 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
2387 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2389 stop_soon
= inf
->stop_soon
;
2392 stop_soon
= NO_STOP_QUIETLY
;
2394 /* Cache the last pid/waitstatus. */
2395 target_last_wait_ptid
= ecs
->ptid
;
2396 target_last_waitstatus
= ecs
->ws
;
2398 /* Always clear state belonging to the previous time we stopped. */
2399 stop_stack_dummy
= 0;
2401 /* If it's a new process, add it to the thread database */
2403 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
2404 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
2405 && !in_thread_list (ecs
->ptid
));
2407 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2408 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
2409 add_thread (ecs
->ptid
);
2411 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
2413 /* Dependent on valid ECS->EVENT_THREAD. */
2414 adjust_pc_after_break (ecs
);
2416 /* Dependent on the current PC value modified by adjust_pc_after_break. */
2417 reinit_frame_cache ();
2419 if (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
2421 breakpoint_retire_moribund ();
2423 /* Mark the non-executing threads accordingly. In all-stop, all
2424 threads of all processes are stopped when we get any event
2425 reported. In non-stop mode, only the event thread stops. If
2426 we're handling a process exit in non-stop mode, there's
2427 nothing to do, as threads of the dead process are gone, and
2428 threads of any other process were left running. */
2430 set_executing (minus_one_ptid
, 0);
2431 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2432 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
2433 set_executing (inferior_ptid
, 0);
2436 switch (infwait_state
)
2438 case infwait_thread_hop_state
:
2440 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
2441 /* Cancel the waiton_ptid. */
2442 waiton_ptid
= pid_to_ptid (-1);
2445 case infwait_normal_state
:
2447 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
2450 case infwait_step_watch_state
:
2452 fprintf_unfiltered (gdb_stdlog
,
2453 "infrun: infwait_step_watch_state\n");
2455 stepped_after_stopped_by_watchpoint
= 1;
2458 case infwait_nonstep_watch_state
:
2460 fprintf_unfiltered (gdb_stdlog
,
2461 "infrun: infwait_nonstep_watch_state\n");
2462 insert_breakpoints ();
2464 /* FIXME-maybe: is this cleaner than setting a flag? Does it
2465 handle things like signals arriving and other things happening
2466 in combination correctly? */
2467 stepped_after_stopped_by_watchpoint
= 1;
2471 internal_error (__FILE__
, __LINE__
, _("bad switch"));
2473 infwait_state
= infwait_normal_state
;
2475 switch (ecs
->ws
.kind
)
2477 case TARGET_WAITKIND_LOADED
:
2479 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
2480 /* Ignore gracefully during startup of the inferior, as it might
2481 be the shell which has just loaded some objects, otherwise
2482 add the symbols for the newly loaded objects. Also ignore at
2483 the beginning of an attach or remote session; we will query
2484 the full list of libraries once the connection is
2486 if (stop_soon
== NO_STOP_QUIETLY
)
2488 /* Check for any newly added shared libraries if we're
2489 supposed to be adding them automatically. Switch
2490 terminal for any messages produced by
2491 breakpoint_re_set. */
2492 target_terminal_ours_for_output ();
2493 /* NOTE: cagney/2003-11-25: Make certain that the target
2494 stack's section table is kept up-to-date. Architectures,
2495 (e.g., PPC64), use the section table to perform
2496 operations such as address => section name and hence
2497 require the table to contain all sections (including
2498 those found in shared libraries). */
2500 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2502 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2504 target_terminal_inferior ();
2506 /* If requested, stop when the dynamic linker notifies
2507 gdb of events. This allows the user to get control
2508 and place breakpoints in initializer routines for
2509 dynamically loaded objects (among other things). */
2510 if (stop_on_solib_events
)
2512 stop_stepping (ecs
);
2516 /* NOTE drow/2007-05-11: This might be a good place to check
2517 for "catch load". */
2520 /* If we are skipping through a shell, or through shared library
2521 loading that we aren't interested in, resume the program. If
2522 we're running the program normally, also resume. But stop if
2523 we're attaching or setting up a remote connection. */
2524 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
2526 /* Loading of shared libraries might have changed breakpoint
2527 addresses. Make sure new breakpoints are inserted. */
2528 if (stop_soon
== NO_STOP_QUIETLY
2529 && !breakpoints_always_inserted_mode ())
2530 insert_breakpoints ();
2531 resume (0, TARGET_SIGNAL_0
);
2532 prepare_to_wait (ecs
);
2538 case TARGET_WAITKIND_SPURIOUS
:
2540 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
2541 resume (0, TARGET_SIGNAL_0
);
2542 prepare_to_wait (ecs
);
2545 case TARGET_WAITKIND_EXITED
:
2547 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
2548 inferior_ptid
= ecs
->ptid
;
2549 target_terminal_ours (); /* Must do this before mourn anyway */
2550 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
2552 /* Record the exit code in the convenience variable $_exitcode, so
2553 that the user can inspect this again later. */
2554 set_internalvar_integer (lookup_internalvar ("_exitcode"),
2555 (LONGEST
) ecs
->ws
.value
.integer
);
2556 gdb_flush (gdb_stdout
);
2557 target_mourn_inferior ();
2558 singlestep_breakpoints_inserted_p
= 0;
2559 stop_print_frame
= 0;
2560 stop_stepping (ecs
);
2563 case TARGET_WAITKIND_SIGNALLED
:
2565 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2566 inferior_ptid
= ecs
->ptid
;
2567 stop_print_frame
= 0;
2568 target_terminal_ours (); /* Must do this before mourn anyway */
2570 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2571 reach here unless the inferior is dead. However, for years
2572 target_kill() was called here, which hints that fatal signals aren't
2573 really fatal on some systems. If that's true, then some changes
2575 target_mourn_inferior ();
2577 print_stop_reason (SIGNAL_EXITED
, ecs
->ws
.value
.sig
);
2578 singlestep_breakpoints_inserted_p
= 0;
2579 stop_stepping (ecs
);
2582 /* The following are the only cases in which we keep going;
2583 the above cases end in a continue or goto. */
2584 case TARGET_WAITKIND_FORKED
:
2585 case TARGET_WAITKIND_VFORKED
:
2587 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2589 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2591 context_switch (ecs
->ptid
);
2592 reinit_frame_cache ();
2595 /* Immediately detach breakpoints from the child before there's
2596 any chance of letting the user delete breakpoints from the
2597 breakpoint lists. If we don't do this early, it's easy to
2598 leave left over traps in the child, vis: "break foo; catch
2599 fork; c; <fork>; del; c; <child calls foo>". We only follow
2600 the fork on the last `continue', and by that time the
2601 breakpoint at "foo" is long gone from the breakpoint table.
2602 If we vforked, then we don't need to unpatch here, since both
2603 parent and child are sharing the same memory pages; we'll
2604 need to unpatch at follow/detach time instead to be certain
2605 that new breakpoints added between catchpoint hit time and
2606 vfork follow are detached. */
2607 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
2609 int child_pid
= ptid_get_pid (ecs
->ws
.value
.related_pid
);
2611 /* This won't actually modify the breakpoint list, but will
2612 physically remove the breakpoints from the child. */
2613 detach_breakpoints (child_pid
);
2616 /* In case the event is caught by a catchpoint, remember that
2617 the event is to be followed at the next resume of the thread,
2618 and not immediately. */
2619 ecs
->event_thread
->pending_follow
= ecs
->ws
;
2621 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2623 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2625 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2627 /* If no catchpoint triggered for this, then keep going. */
2628 if (ecs
->random_signal
)
2632 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2634 should_resume
= follow_fork ();
2636 ecs
->event_thread
= inferior_thread ();
2637 ecs
->ptid
= inferior_ptid
;
2642 stop_stepping (ecs
);
2645 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2646 goto process_event_stop_test
;
2648 case TARGET_WAITKIND_EXECD
:
2650 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
2652 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2654 context_switch (ecs
->ptid
);
2655 reinit_frame_cache ();
2658 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2660 /* This causes the eventpoints and symbol table to be reset.
2661 Must do this now, before trying to determine whether to
2663 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
2665 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2666 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2668 /* Note that this may be referenced from inside
2669 bpstat_stop_status above, through inferior_has_execd. */
2670 xfree (ecs
->ws
.value
.execd_pathname
);
2671 ecs
->ws
.value
.execd_pathname
= NULL
;
2673 /* If no catchpoint triggered for this, then keep going. */
2674 if (ecs
->random_signal
)
2676 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2680 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2681 goto process_event_stop_test
;
2683 /* Be careful not to try to gather much state about a thread
2684 that's in a syscall. It's frequently a losing proposition. */
2685 case TARGET_WAITKIND_SYSCALL_ENTRY
:
2687 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2688 resume (0, TARGET_SIGNAL_0
);
2689 prepare_to_wait (ecs
);
2692 /* Before examining the threads further, step this thread to
2693 get it entirely out of the syscall. (We get notice of the
2694 event when the thread is just on the verge of exiting a
2695 syscall. Stepping one instruction seems to get it back
2697 case TARGET_WAITKIND_SYSCALL_RETURN
:
2699 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2700 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
);
2701 prepare_to_wait (ecs
);
2704 case TARGET_WAITKIND_STOPPED
:
2706 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
2707 ecs
->event_thread
->stop_signal
= ecs
->ws
.value
.sig
;
2710 case TARGET_WAITKIND_NO_HISTORY
:
2711 /* Reverse execution: target ran out of history info. */
2712 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2713 print_stop_reason (NO_HISTORY
, 0);
2714 stop_stepping (ecs
);
2717 /* We had an event in the inferior, but we are not interested
2718 in handling it at this level. The lower layers have already
2719 done what needs to be done, if anything.
2721 One of the possible circumstances for this is when the
2722 inferior produces output for the console. The inferior has
2723 not stopped, and we are ignoring the event. Another possible
2724 circumstance is any event which the lower level knows will be
2725 reported multiple times without an intervening resume. */
2726 case TARGET_WAITKIND_IGNORE
:
2728 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2729 prepare_to_wait (ecs
);
2733 if (ecs
->new_thread_event
)
2736 /* Non-stop assumes that the target handles adding new threads
2737 to the thread list. */
2738 internal_error (__FILE__
, __LINE__
, "\
2739 targets should add new threads to the thread list themselves in non-stop mode.");
2741 /* We may want to consider not doing a resume here in order to
2742 give the user a chance to play with the new thread. It might
2743 be good to make that a user-settable option. */
2745 /* At this point, all threads are stopped (happens automatically
2746 in either the OS or the native code). Therefore we need to
2747 continue all threads in order to make progress. */
2749 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2750 context_switch (ecs
->ptid
);
2751 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
2752 prepare_to_wait (ecs
);
2756 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
2758 /* Do we need to clean up the state of a thread that has
2759 completed a displaced single-step? (Doing so usually affects
2760 the PC, so do it here, before we set stop_pc.) */
2761 displaced_step_fixup (ecs
->ptid
, ecs
->event_thread
->stop_signal
);
2763 /* If we either finished a single-step or hit a breakpoint, but
2764 the user wanted this thread to be stopped, pretend we got a
2765 SIG0 (generic unsignaled stop). */
2767 if (ecs
->event_thread
->stop_requested
2768 && ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2769 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2772 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2776 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = 0x%s\n",
2777 paddr_nz (stop_pc
));
2778 if (target_stopped_by_watchpoint ())
2781 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
2783 if (target_stopped_data_address (¤t_target
, &addr
))
2784 fprintf_unfiltered (gdb_stdlog
,
2785 "infrun: stopped data address = 0x%s\n",
2788 fprintf_unfiltered (gdb_stdlog
,
2789 "infrun: (no data address available)\n");
2793 if (stepping_past_singlestep_breakpoint
)
2795 gdb_assert (singlestep_breakpoints_inserted_p
);
2796 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
2797 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
2799 stepping_past_singlestep_breakpoint
= 0;
2801 /* We've either finished single-stepping past the single-step
2802 breakpoint, or stopped for some other reason. It would be nice if
2803 we could tell, but we can't reliably. */
2804 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2807 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
2808 /* Pull the single step breakpoints out of the target. */
2809 remove_single_step_breakpoints ();
2810 singlestep_breakpoints_inserted_p
= 0;
2812 ecs
->random_signal
= 0;
2814 context_switch (saved_singlestep_ptid
);
2815 if (deprecated_context_hook
)
2816 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2818 resume (1, TARGET_SIGNAL_0
);
2819 prepare_to_wait (ecs
);
2824 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
2826 /* In non-stop mode, there's never a deferred_step_ptid set. */
2827 gdb_assert (!non_stop
);
2829 /* If we stopped for some other reason than single-stepping, ignore
2830 the fact that we were supposed to switch back. */
2831 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2834 fprintf_unfiltered (gdb_stdlog
,
2835 "infrun: handling deferred step\n");
2837 /* Pull the single step breakpoints out of the target. */
2838 if (singlestep_breakpoints_inserted_p
)
2840 remove_single_step_breakpoints ();
2841 singlestep_breakpoints_inserted_p
= 0;
2844 /* Note: We do not call context_switch at this point, as the
2845 context is already set up for stepping the original thread. */
2846 switch_to_thread (deferred_step_ptid
);
2847 deferred_step_ptid
= null_ptid
;
2848 /* Suppress spurious "Switching to ..." message. */
2849 previous_inferior_ptid
= inferior_ptid
;
2851 resume (1, TARGET_SIGNAL_0
);
2852 prepare_to_wait (ecs
);
2856 deferred_step_ptid
= null_ptid
;
2859 /* See if a thread hit a thread-specific breakpoint that was meant for
2860 another thread. If so, then step that thread past the breakpoint,
2863 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2865 int thread_hop_needed
= 0;
2867 /* Check if a regular breakpoint has been hit before checking
2868 for a potential single step breakpoint. Otherwise, GDB will
2869 not see this breakpoint hit when stepping onto breakpoints. */
2870 if (regular_breakpoint_inserted_here_p (stop_pc
))
2872 ecs
->random_signal
= 0;
2873 if (!breakpoint_thread_match (stop_pc
, ecs
->ptid
))
2874 thread_hop_needed
= 1;
2876 else if (singlestep_breakpoints_inserted_p
)
2878 /* We have not context switched yet, so this should be true
2879 no matter which thread hit the singlestep breakpoint. */
2880 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
2882 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
2884 target_pid_to_str (ecs
->ptid
));
2886 ecs
->random_signal
= 0;
2887 /* The call to in_thread_list is necessary because PTIDs sometimes
2888 change when we go from single-threaded to multi-threaded. If
2889 the singlestep_ptid is still in the list, assume that it is
2890 really different from ecs->ptid. */
2891 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
2892 && in_thread_list (singlestep_ptid
))
2894 /* If the PC of the thread we were trying to single-step
2895 has changed, discard this event (which we were going
2896 to ignore anyway), and pretend we saw that thread
2897 trap. This prevents us continuously moving the
2898 single-step breakpoint forward, one instruction at a
2899 time. If the PC has changed, then the thread we were
2900 trying to single-step has trapped or been signalled,
2901 but the event has not been reported to GDB yet.
2903 There might be some cases where this loses signal
2904 information, if a signal has arrived at exactly the
2905 same time that the PC changed, but this is the best
2906 we can do with the information available. Perhaps we
2907 should arrange to report all events for all threads
2908 when they stop, or to re-poll the remote looking for
2909 this particular thread (i.e. temporarily enable
2912 CORE_ADDR new_singlestep_pc
2913 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
2915 if (new_singlestep_pc
!= singlestep_pc
)
2917 enum target_signal stop_signal
;
2920 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
2921 " but expected thread advanced also\n");
2923 /* The current context still belongs to
2924 singlestep_ptid. Don't swap here, since that's
2925 the context we want to use. Just fudge our
2926 state and continue. */
2927 stop_signal
= ecs
->event_thread
->stop_signal
;
2928 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2929 ecs
->ptid
= singlestep_ptid
;
2930 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
2931 ecs
->event_thread
->stop_signal
= stop_signal
;
2932 stop_pc
= new_singlestep_pc
;
2937 fprintf_unfiltered (gdb_stdlog
,
2938 "infrun: unexpected thread\n");
2940 thread_hop_needed
= 1;
2941 stepping_past_singlestep_breakpoint
= 1;
2942 saved_singlestep_ptid
= singlestep_ptid
;
2947 if (thread_hop_needed
)
2949 struct regcache
*thread_regcache
;
2950 int remove_status
= 0;
2953 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
2955 /* Switch context before touching inferior memory, the
2956 previous thread may have exited. */
2957 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
2958 context_switch (ecs
->ptid
);
2960 /* Saw a breakpoint, but it was hit by the wrong thread.
2963 if (singlestep_breakpoints_inserted_p
)
2965 /* Pull the single step breakpoints out of the target. */
2966 remove_single_step_breakpoints ();
2967 singlestep_breakpoints_inserted_p
= 0;
2970 /* If the arch can displace step, don't remove the
2972 thread_regcache
= get_thread_regcache (ecs
->ptid
);
2973 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
2974 remove_status
= remove_breakpoints ();
2976 /* Did we fail to remove breakpoints? If so, try
2977 to set the PC past the bp. (There's at least
2978 one situation in which we can fail to remove
2979 the bp's: On HP-UX's that use ttrace, we can't
2980 change the address space of a vforking child
2981 process until the child exits (well, okay, not
2982 then either :-) or execs. */
2983 if (remove_status
!= 0)
2984 error (_("Cannot step over breakpoint hit in wrong thread"));
2989 /* Only need to require the next event from this
2990 thread in all-stop mode. */
2991 waiton_ptid
= ecs
->ptid
;
2992 infwait_state
= infwait_thread_hop_state
;
2995 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2997 registers_changed ();
3001 else if (singlestep_breakpoints_inserted_p
)
3003 sw_single_step_trap_p
= 1;
3004 ecs
->random_signal
= 0;
3008 ecs
->random_signal
= 1;
3010 /* See if something interesting happened to the non-current thread. If
3011 so, then switch to that thread. */
3012 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3015 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3017 context_switch (ecs
->ptid
);
3019 if (deprecated_context_hook
)
3020 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3023 /* At this point, get hold of the now-current thread's frame. */
3024 frame
= get_current_frame ();
3025 gdbarch
= get_frame_arch (frame
);
3027 if (singlestep_breakpoints_inserted_p
)
3029 /* Pull the single step breakpoints out of the target. */
3030 remove_single_step_breakpoints ();
3031 singlestep_breakpoints_inserted_p
= 0;
3034 if (stepped_after_stopped_by_watchpoint
)
3035 stopped_by_watchpoint
= 0;
3037 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
3039 /* If necessary, step over this watchpoint. We'll be back to display
3041 if (stopped_by_watchpoint
3042 && (target_have_steppable_watchpoint
3043 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
3045 /* At this point, we are stopped at an instruction which has
3046 attempted to write to a piece of memory under control of
3047 a watchpoint. The instruction hasn't actually executed
3048 yet. If we were to evaluate the watchpoint expression
3049 now, we would get the old value, and therefore no change
3050 would seem to have occurred.
3052 In order to make watchpoints work `right', we really need
3053 to complete the memory write, and then evaluate the
3054 watchpoint expression. We do this by single-stepping the
3057 It may not be necessary to disable the watchpoint to stop over
3058 it. For example, the PA can (with some kernel cooperation)
3059 single step over a watchpoint without disabling the watchpoint.
3061 It is far more common to need to disable a watchpoint to step
3062 the inferior over it. If we have non-steppable watchpoints,
3063 we must disable the current watchpoint; it's simplest to
3064 disable all watchpoints and breakpoints. */
3067 if (!target_have_steppable_watchpoint
)
3068 remove_breakpoints ();
3070 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
3071 target_resume (ecs
->ptid
, hw_step
, TARGET_SIGNAL_0
);
3072 registers_changed ();
3073 waiton_ptid
= ecs
->ptid
;
3074 if (target_have_steppable_watchpoint
)
3075 infwait_state
= infwait_step_watch_state
;
3077 infwait_state
= infwait_nonstep_watch_state
;
3078 prepare_to_wait (ecs
);
3082 ecs
->stop_func_start
= 0;
3083 ecs
->stop_func_end
= 0;
3084 ecs
->stop_func_name
= 0;
3085 /* Don't care about return value; stop_func_start and stop_func_name
3086 will both be 0 if it doesn't work. */
3087 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3088 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3089 ecs
->stop_func_start
3090 += gdbarch_deprecated_function_start_offset (gdbarch
);
3091 ecs
->event_thread
->stepping_over_breakpoint
= 0;
3092 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
3093 ecs
->event_thread
->stop_step
= 0;
3094 stop_print_frame
= 1;
3095 ecs
->random_signal
= 0;
3096 stopped_by_random_signal
= 0;
3098 /* Hide inlined functions starting here, unless we just performed stepi or
3099 nexti. After stepi and nexti, always show the innermost frame (not any
3100 inline function call sites). */
3101 if (ecs
->event_thread
->step_range_end
!= 1)
3102 skip_inline_frames (ecs
->ptid
);
3104 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3105 && ecs
->event_thread
->trap_expected
3106 && gdbarch_single_step_through_delay_p (gdbarch
)
3107 && currently_stepping (ecs
->event_thread
))
3109 /* We're trying to step off a breakpoint. Turns out that we're
3110 also on an instruction that needs to be stepped multiple
3111 times before it's been fully executing. E.g., architectures
3112 with a delay slot. It needs to be stepped twice, once for
3113 the instruction and once for the delay slot. */
3114 int step_through_delay
3115 = gdbarch_single_step_through_delay (gdbarch
, frame
);
3116 if (debug_infrun
&& step_through_delay
)
3117 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
3118 if (ecs
->event_thread
->step_range_end
== 0 && step_through_delay
)
3120 /* The user issued a continue when stopped at a breakpoint.
3121 Set up for another trap and get out of here. */
3122 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3126 else if (step_through_delay
)
3128 /* The user issued a step when stopped at a breakpoint.
3129 Maybe we should stop, maybe we should not - the delay
3130 slot *might* correspond to a line of source. In any
3131 case, don't decide that here, just set
3132 ecs->stepping_over_breakpoint, making sure we
3133 single-step again before breakpoints are re-inserted. */
3134 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3138 /* Look at the cause of the stop, and decide what to do.
3139 The alternatives are:
3140 1) stop_stepping and return; to really stop and return to the debugger,
3141 2) keep_going and return to start up again
3142 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
3143 3) set ecs->random_signal to 1, and the decision between 1 and 2
3144 will be made according to the signal handling tables. */
3146 /* First, distinguish signals caused by the debugger from signals
3147 that have to do with the program's own actions. Note that
3148 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3149 on the operating system version. Here we detect when a SIGILL or
3150 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3151 something similar for SIGSEGV, since a SIGSEGV will be generated
3152 when we're trying to execute a breakpoint instruction on a
3153 non-executable stack. This happens for call dummy breakpoints
3154 for architectures like SPARC that place call dummies on the
3157 If we're doing a displaced step past a breakpoint, then the
3158 breakpoint is always inserted at the original instruction;
3159 non-standard signals can't be explained by the breakpoint. */
3160 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3161 || (! ecs
->event_thread
->trap_expected
3162 && breakpoint_inserted_here_p (stop_pc
)
3163 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_ILL
3164 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_SEGV
3165 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_EMT
))
3166 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3167 || stop_soon
== STOP_QUIETLY_REMOTE
)
3169 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
3172 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
3173 stop_print_frame
= 0;
3174 stop_stepping (ecs
);
3178 /* This is originated from start_remote(), start_inferior() and
3179 shared libraries hook functions. */
3180 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
3183 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3184 stop_stepping (ecs
);
3188 /* This originates from attach_command(). We need to overwrite
3189 the stop_signal here, because some kernels don't ignore a
3190 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
3191 See more comments in inferior.h. On the other hand, if we
3192 get a non-SIGSTOP, report it to the user - assume the backend
3193 will handle the SIGSTOP if it should show up later.
3195 Also consider that the attach is complete when we see a
3196 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
3197 target extended-remote report it instead of a SIGSTOP
3198 (e.g. gdbserver). We already rely on SIGTRAP being our
3199 signal, so this is no exception.
3201 Also consider that the attach is complete when we see a
3202 TARGET_SIGNAL_0. In non-stop mode, GDB will explicitly tell
3203 the target to stop all threads of the inferior, in case the
3204 low level attach operation doesn't stop them implicitly. If
3205 they weren't stopped implicitly, then the stub will report a
3206 TARGET_SIGNAL_0, meaning: stopped for no particular reason
3207 other than GDB's request. */
3208 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3209 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_STOP
3210 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3211 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_0
))
3213 stop_stepping (ecs
);
3214 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3218 /* See if there is a breakpoint at the current PC. */
3219 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
3221 /* Following in case break condition called a
3223 stop_print_frame
= 1;
3225 /* NOTE: cagney/2003-03-29: These two checks for a random signal
3226 at one stage in the past included checks for an inferior
3227 function call's call dummy's return breakpoint. The original
3228 comment, that went with the test, read:
3230 ``End of a stack dummy. Some systems (e.g. Sony news) give
3231 another signal besides SIGTRAP, so check here as well as
3234 If someone ever tries to get call dummys on a
3235 non-executable stack to work (where the target would stop
3236 with something like a SIGSEGV), then those tests might need
3237 to be re-instated. Given, however, that the tests were only
3238 enabled when momentary breakpoints were not being used, I
3239 suspect that it won't be the case.
3241 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
3242 be necessary for call dummies on a non-executable stack on
3245 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
3247 = !(bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
)
3248 || ecs
->event_thread
->trap_expected
3249 || (ecs
->event_thread
->step_range_end
3250 && ecs
->event_thread
->step_resume_breakpoint
== NULL
));
3253 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
3254 if (!ecs
->random_signal
)
3255 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
3259 /* When we reach this point, we've pretty much decided
3260 that the reason for stopping must've been a random
3261 (unexpected) signal. */
3264 ecs
->random_signal
= 1;
3266 process_event_stop_test
:
3268 /* Re-fetch current thread's frame in case we did a
3269 "goto process_event_stop_test" above. */
3270 frame
= get_current_frame ();
3271 gdbarch
= get_frame_arch (frame
);
3273 /* For the program's own signals, act according to
3274 the signal handling tables. */
3276 if (ecs
->random_signal
)
3278 /* Signal not for debugging purposes. */
3282 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
3283 ecs
->event_thread
->stop_signal
);
3285 stopped_by_random_signal
= 1;
3287 if (signal_print
[ecs
->event_thread
->stop_signal
])
3290 target_terminal_ours_for_output ();
3291 print_stop_reason (SIGNAL_RECEIVED
, ecs
->event_thread
->stop_signal
);
3293 /* Always stop on signals if we're either just gaining control
3294 of the program, or the user explicitly requested this thread
3295 to remain stopped. */
3296 if (stop_soon
!= NO_STOP_QUIETLY
3297 || ecs
->event_thread
->stop_requested
3298 || signal_stop_state (ecs
->event_thread
->stop_signal
))
3300 stop_stepping (ecs
);
3303 /* If not going to stop, give terminal back
3304 if we took it away. */
3306 target_terminal_inferior ();
3308 /* Clear the signal if it should not be passed. */
3309 if (signal_program
[ecs
->event_thread
->stop_signal
] == 0)
3310 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3312 if (ecs
->event_thread
->prev_pc
== stop_pc
3313 && ecs
->event_thread
->trap_expected
3314 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
3316 /* We were just starting a new sequence, attempting to
3317 single-step off of a breakpoint and expecting a SIGTRAP.
3318 Instead this signal arrives. This signal will take us out
3319 of the stepping range so GDB needs to remember to, when
3320 the signal handler returns, resume stepping off that
3322 /* To simplify things, "continue" is forced to use the same
3323 code paths as single-step - set a breakpoint at the
3324 signal return address and then, once hit, step off that
3327 fprintf_unfiltered (gdb_stdlog
,
3328 "infrun: signal arrived while stepping over "
3331 insert_step_resume_breakpoint_at_frame (frame
);
3332 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
3337 if (ecs
->event_thread
->step_range_end
!= 0
3338 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_0
3339 && (ecs
->event_thread
->step_range_start
<= stop_pc
3340 && stop_pc
< ecs
->event_thread
->step_range_end
)
3341 && frame_id_eq (get_stack_frame_id (frame
),
3342 ecs
->event_thread
->step_stack_frame_id
)
3343 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
3345 /* The inferior is about to take a signal that will take it
3346 out of the single step range. Set a breakpoint at the
3347 current PC (which is presumably where the signal handler
3348 will eventually return) and then allow the inferior to
3351 Note that this is only needed for a signal delivered
3352 while in the single-step range. Nested signals aren't a
3353 problem as they eventually all return. */
3355 fprintf_unfiltered (gdb_stdlog
,
3356 "infrun: signal may take us out of "
3357 "single-step range\n");
3359 insert_step_resume_breakpoint_at_frame (frame
);
3364 /* Note: step_resume_breakpoint may be non-NULL. This occures
3365 when either there's a nested signal, or when there's a
3366 pending signal enabled just as the signal handler returns
3367 (leaving the inferior at the step-resume-breakpoint without
3368 actually executing it). Either way continue until the
3369 breakpoint is really hit. */
3374 /* Handle cases caused by hitting a breakpoint. */
3376 CORE_ADDR jmp_buf_pc
;
3377 struct bpstat_what what
;
3379 what
= bpstat_what (ecs
->event_thread
->stop_bpstat
);
3381 if (what
.call_dummy
)
3383 stop_stack_dummy
= 1;
3386 switch (what
.main_action
)
3388 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
3389 /* If we hit the breakpoint at longjmp while stepping, we
3390 install a momentary breakpoint at the target of the
3394 fprintf_unfiltered (gdb_stdlog
,
3395 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
3397 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3399 if (!gdbarch_get_longjmp_target_p (gdbarch
)
3400 || !gdbarch_get_longjmp_target (gdbarch
, frame
, &jmp_buf_pc
))
3403 fprintf_unfiltered (gdb_stdlog
, "\
3404 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
3409 /* We're going to replace the current step-resume breakpoint
3410 with a longjmp-resume breakpoint. */
3411 delete_step_resume_breakpoint (ecs
->event_thread
);
3413 /* Insert a breakpoint at resume address. */
3414 insert_longjmp_resume_breakpoint (jmp_buf_pc
);
3419 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
3421 fprintf_unfiltered (gdb_stdlog
,
3422 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
3424 gdb_assert (ecs
->event_thread
->step_resume_breakpoint
!= NULL
);
3425 delete_step_resume_breakpoint (ecs
->event_thread
);
3427 ecs
->event_thread
->stop_step
= 1;
3428 print_stop_reason (END_STEPPING_RANGE
, 0);
3429 stop_stepping (ecs
);
3432 case BPSTAT_WHAT_SINGLE
:
3434 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
3435 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3436 /* Still need to check other stuff, at least the case
3437 where we are stepping and step out of the right range. */
3440 case BPSTAT_WHAT_STOP_NOISY
:
3442 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
3443 stop_print_frame
= 1;
3445 /* We are about to nuke the step_resume_breakpointt via the
3446 cleanup chain, so no need to worry about it here. */
3448 stop_stepping (ecs
);
3451 case BPSTAT_WHAT_STOP_SILENT
:
3453 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
3454 stop_print_frame
= 0;
3456 /* We are about to nuke the step_resume_breakpoin via the
3457 cleanup chain, so no need to worry about it here. */
3459 stop_stepping (ecs
);
3462 case BPSTAT_WHAT_STEP_RESUME
:
3464 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
3466 delete_step_resume_breakpoint (ecs
->event_thread
);
3467 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
3469 /* Back when the step-resume breakpoint was inserted, we
3470 were trying to single-step off a breakpoint. Go back
3472 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
3473 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3477 if (stop_pc
== ecs
->stop_func_start
3478 && execution_direction
== EXEC_REVERSE
)
3480 /* We are stepping over a function call in reverse, and
3481 just hit the step-resume breakpoint at the start
3482 address of the function. Go back to single-stepping,
3483 which should take us back to the function call. */
3484 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3490 case BPSTAT_WHAT_CHECK_SHLIBS
:
3493 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
3495 /* Check for any newly added shared libraries if we're
3496 supposed to be adding them automatically. Switch
3497 terminal for any messages produced by
3498 breakpoint_re_set. */
3499 target_terminal_ours_for_output ();
3500 /* NOTE: cagney/2003-11-25: Make certain that the target
3501 stack's section table is kept up-to-date. Architectures,
3502 (e.g., PPC64), use the section table to perform
3503 operations such as address => section name and hence
3504 require the table to contain all sections (including
3505 those found in shared libraries). */
3507 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
3509 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
3511 target_terminal_inferior ();
3513 /* If requested, stop when the dynamic linker notifies
3514 gdb of events. This allows the user to get control
3515 and place breakpoints in initializer routines for
3516 dynamically loaded objects (among other things). */
3517 if (stop_on_solib_events
|| stop_stack_dummy
)
3519 stop_stepping (ecs
);
3524 /* We want to step over this breakpoint, then keep going. */
3525 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3531 case BPSTAT_WHAT_LAST
:
3532 /* Not a real code, but listed here to shut up gcc -Wall. */
3534 case BPSTAT_WHAT_KEEP_CHECKING
:
3539 /* We come here if we hit a breakpoint but should not
3540 stop for it. Possibly we also were stepping
3541 and should stop for that. So fall through and
3542 test for stepping. But, if not stepping,
3545 /* In all-stop mode, if we're currently stepping but have stopped in
3546 some other thread, we need to switch back to the stepped thread. */
3549 struct thread_info
*tp
;
3550 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
3554 /* However, if the current thread is blocked on some internal
3555 breakpoint, and we simply need to step over that breakpoint
3556 to get it going again, do that first. */
3557 if ((ecs
->event_thread
->trap_expected
3558 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
3559 || ecs
->event_thread
->stepping_over_breakpoint
)
3565 /* If the stepping thread exited, then don't try to switch
3566 back and resume it, which could fail in several different
3567 ways depending on the target. Instead, just keep going.
3569 We can find a stepping dead thread in the thread list in
3572 - The target supports thread exit events, and when the
3573 target tries to delete the thread from the thread list,
3574 inferior_ptid pointed at the exiting thread. In such
3575 case, calling delete_thread does not really remove the
3576 thread from the list; instead, the thread is left listed,
3577 with 'exited' state.
3579 - The target's debug interface does not support thread
3580 exit events, and so we have no idea whatsoever if the
3581 previously stepping thread is still alive. For that
3582 reason, we need to synchronously query the target
3584 if (is_exited (tp
->ptid
)
3585 || !target_thread_alive (tp
->ptid
))
3588 fprintf_unfiltered (gdb_stdlog
, "\
3589 infrun: not switching back to stepped thread, it has vanished\n");
3591 delete_thread (tp
->ptid
);
3596 /* Otherwise, we no longer expect a trap in the current thread.
3597 Clear the trap_expected flag before switching back -- this is
3598 what keep_going would do as well, if we called it. */
3599 ecs
->event_thread
->trap_expected
= 0;
3602 fprintf_unfiltered (gdb_stdlog
,
3603 "infrun: switching back to stepped thread\n");
3605 ecs
->event_thread
= tp
;
3606 ecs
->ptid
= tp
->ptid
;
3607 context_switch (ecs
->ptid
);
3613 /* Are we stepping to get the inferior out of the dynamic linker's
3614 hook (and possibly the dld itself) after catching a shlib
3616 if (ecs
->event_thread
->stepping_through_solib_after_catch
)
3618 #if defined(SOLIB_ADD)
3619 /* Have we reached our destination? If not, keep going. */
3620 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
3623 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
3624 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3630 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
3631 /* Else, stop and report the catchpoint(s) whose triggering
3632 caused us to begin stepping. */
3633 ecs
->event_thread
->stepping_through_solib_after_catch
= 0;
3634 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
3635 ecs
->event_thread
->stop_bpstat
3636 = bpstat_copy (ecs
->event_thread
->stepping_through_solib_catchpoints
);
3637 bpstat_clear (&ecs
->event_thread
->stepping_through_solib_catchpoints
);
3638 stop_print_frame
= 1;
3639 stop_stepping (ecs
);
3643 if (ecs
->event_thread
->step_resume_breakpoint
)
3646 fprintf_unfiltered (gdb_stdlog
,
3647 "infrun: step-resume breakpoint is inserted\n");
3649 /* Having a step-resume breakpoint overrides anything
3650 else having to do with stepping commands until
3651 that breakpoint is reached. */
3656 if (ecs
->event_thread
->step_range_end
== 0)
3659 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
3660 /* Likewise if we aren't even stepping. */
3665 /* If stepping through a line, keep going if still within it.
3667 Note that step_range_end is the address of the first instruction
3668 beyond the step range, and NOT the address of the last instruction
3671 Note also that during reverse execution, we may be stepping
3672 through a function epilogue and therefore must detect when
3673 the current-frame changes in the middle of a line. */
3675 if (stop_pc
>= ecs
->event_thread
->step_range_start
3676 && stop_pc
< ecs
->event_thread
->step_range_end
3677 && (execution_direction
!= EXEC_REVERSE
3678 || frame_id_eq (get_frame_id (frame
),
3679 ecs
->event_thread
->step_frame_id
)))
3682 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping inside range [0x%s-0x%s]\n",
3683 paddr_nz (ecs
->event_thread
->step_range_start
),
3684 paddr_nz (ecs
->event_thread
->step_range_end
));
3686 /* When stepping backward, stop at beginning of line range
3687 (unless it's the function entry point, in which case
3688 keep going back to the call point). */
3689 if (stop_pc
== ecs
->event_thread
->step_range_start
3690 && stop_pc
!= ecs
->stop_func_start
3691 && execution_direction
== EXEC_REVERSE
)
3693 ecs
->event_thread
->stop_step
= 1;
3694 print_stop_reason (END_STEPPING_RANGE
, 0);
3695 stop_stepping (ecs
);
3703 /* We stepped out of the stepping range. */
3705 /* If we are stepping at the source level and entered the runtime
3706 loader dynamic symbol resolution code...
3708 EXEC_FORWARD: we keep on single stepping until we exit the run
3709 time loader code and reach the callee's address.
3711 EXEC_REVERSE: we've already executed the callee (backward), and
3712 the runtime loader code is handled just like any other
3713 undebuggable function call. Now we need only keep stepping
3714 backward through the trampoline code, and that's handled further
3715 down, so there is nothing for us to do here. */
3717 if (execution_direction
!= EXEC_REVERSE
3718 && ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3719 && in_solib_dynsym_resolve_code (stop_pc
))
3721 CORE_ADDR pc_after_resolver
=
3722 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
3725 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
3727 if (pc_after_resolver
)
3729 /* Set up a step-resume breakpoint at the address
3730 indicated by SKIP_SOLIB_RESOLVER. */
3731 struct symtab_and_line sr_sal
;
3733 sr_sal
.pc
= pc_after_resolver
;
3735 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3742 if (ecs
->event_thread
->step_range_end
!= 1
3743 && (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3744 || ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3745 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
3748 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
3749 /* The inferior, while doing a "step" or "next", has ended up in
3750 a signal trampoline (either by a signal being delivered or by
3751 the signal handler returning). Just single-step until the
3752 inferior leaves the trampoline (either by calling the handler
3758 /* Check for subroutine calls. The check for the current frame
3759 equalling the step ID is not necessary - the check of the
3760 previous frame's ID is sufficient - but it is a common case and
3761 cheaper than checking the previous frame's ID.
3763 NOTE: frame_id_eq will never report two invalid frame IDs as
3764 being equal, so to get into this block, both the current and
3765 previous frame must have valid frame IDs. */
3766 if (!frame_id_eq (get_stack_frame_id (frame
),
3767 ecs
->event_thread
->step_stack_frame_id
)
3768 && (frame_id_eq (frame_unwind_caller_id (frame
),
3769 ecs
->event_thread
->step_stack_frame_id
)
3770 || execution_direction
== EXEC_REVERSE
))
3772 CORE_ADDR real_stop_pc
;
3775 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
3777 if ((ecs
->event_thread
->step_over_calls
== STEP_OVER_NONE
)
3778 || ((ecs
->event_thread
->step_range_end
== 1)
3779 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
3780 ecs
->stop_func_start
)))
3782 /* I presume that step_over_calls is only 0 when we're
3783 supposed to be stepping at the assembly language level
3784 ("stepi"). Just stop. */
3785 /* Also, maybe we just did a "nexti" inside a prolog, so we
3786 thought it was a subroutine call but it was not. Stop as
3788 /* And this works the same backward as frontward. MVS */
3789 ecs
->event_thread
->stop_step
= 1;
3790 print_stop_reason (END_STEPPING_RANGE
, 0);
3791 stop_stepping (ecs
);
3795 /* Reverse stepping through solib trampolines. */
3797 if (execution_direction
== EXEC_REVERSE
3798 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
3799 || (ecs
->stop_func_start
== 0
3800 && in_solib_dynsym_resolve_code (stop_pc
))))
3802 /* Any solib trampoline code can be handled in reverse
3803 by simply continuing to single-step. We have already
3804 executed the solib function (backwards), and a few
3805 steps will take us back through the trampoline to the
3811 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3813 /* We're doing a "next".
3815 Normal (forward) execution: set a breakpoint at the
3816 callee's return address (the address at which the caller
3819 Reverse (backward) execution. set the step-resume
3820 breakpoint at the start of the function that we just
3821 stepped into (backwards), and continue to there. When we
3822 get there, we'll need to single-step back to the caller. */
3824 if (execution_direction
== EXEC_REVERSE
)
3826 struct symtab_and_line sr_sal
;
3828 /* Normal function call return (static or dynamic). */
3830 sr_sal
.pc
= ecs
->stop_func_start
;
3831 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3834 insert_step_resume_breakpoint_at_caller (frame
);
3840 /* If we are in a function call trampoline (a stub between the
3841 calling routine and the real function), locate the real
3842 function. That's what tells us (a) whether we want to step
3843 into it at all, and (b) what prologue we want to run to the
3844 end of, if we do step into it. */
3845 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
3846 if (real_stop_pc
== 0)
3847 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
3848 if (real_stop_pc
!= 0)
3849 ecs
->stop_func_start
= real_stop_pc
;
3851 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
3853 struct symtab_and_line sr_sal
;
3855 sr_sal
.pc
= ecs
->stop_func_start
;
3857 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3862 /* If we have line number information for the function we are
3863 thinking of stepping into, step into it.
3865 If there are several symtabs at that PC (e.g. with include
3866 files), just want to know whether *any* of them have line
3867 numbers. find_pc_line handles this. */
3869 struct symtab_and_line tmp_sal
;
3871 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3872 if (tmp_sal
.line
!= 0)
3874 if (execution_direction
== EXEC_REVERSE
)
3875 handle_step_into_function_backward (gdbarch
, ecs
);
3877 handle_step_into_function (gdbarch
, ecs
);
3882 /* If we have no line number and the step-stop-if-no-debug is
3883 set, we stop the step so that the user has a chance to switch
3884 in assembly mode. */
3885 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3886 && step_stop_if_no_debug
)
3888 ecs
->event_thread
->stop_step
= 1;
3889 print_stop_reason (END_STEPPING_RANGE
, 0);
3890 stop_stepping (ecs
);
3894 if (execution_direction
== EXEC_REVERSE
)
3896 /* Set a breakpoint at callee's start address.
3897 From there we can step once and be back in the caller. */
3898 struct symtab_and_line sr_sal
;
3900 sr_sal
.pc
= ecs
->stop_func_start
;
3901 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3904 /* Set a breakpoint at callee's return address (the address
3905 at which the caller will resume). */
3906 insert_step_resume_breakpoint_at_caller (frame
);
3912 /* If we're in the return path from a shared library trampoline,
3913 we want to proceed through the trampoline when stepping. */
3914 if (gdbarch_in_solib_return_trampoline (gdbarch
,
3915 stop_pc
, ecs
->stop_func_name
))
3917 /* Determine where this trampoline returns. */
3918 CORE_ADDR real_stop_pc
;
3919 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
3922 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
3924 /* Only proceed through if we know where it's going. */
3927 /* And put the step-breakpoint there and go until there. */
3928 struct symtab_and_line sr_sal
;
3930 init_sal (&sr_sal
); /* initialize to zeroes */
3931 sr_sal
.pc
= real_stop_pc
;
3932 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3934 /* Do not specify what the fp should be when we stop since
3935 on some machines the prologue is where the new fp value
3937 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3939 /* Restart without fiddling with the step ranges or
3946 stop_pc_sal
= find_pc_line (stop_pc
, 0);
3948 /* NOTE: tausq/2004-05-24: This if block used to be done before all
3949 the trampoline processing logic, however, there are some trampolines
3950 that have no names, so we should do trampoline handling first. */
3951 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3952 && ecs
->stop_func_name
== NULL
3953 && stop_pc_sal
.line
== 0)
3956 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
3958 /* The inferior just stepped into, or returned to, an
3959 undebuggable function (where there is no debugging information
3960 and no line number corresponding to the address where the
3961 inferior stopped). Since we want to skip this kind of code,
3962 we keep going until the inferior returns from this
3963 function - unless the user has asked us not to (via
3964 set step-mode) or we no longer know how to get back
3965 to the call site. */
3966 if (step_stop_if_no_debug
3967 || !frame_id_p (frame_unwind_caller_id (frame
)))
3969 /* If we have no line number and the step-stop-if-no-debug
3970 is set, we stop the step so that the user has a chance to
3971 switch in assembly mode. */
3972 ecs
->event_thread
->stop_step
= 1;
3973 print_stop_reason (END_STEPPING_RANGE
, 0);
3974 stop_stepping (ecs
);
3979 /* Set a breakpoint at callee's return address (the address
3980 at which the caller will resume). */
3981 insert_step_resume_breakpoint_at_caller (frame
);
3987 if (ecs
->event_thread
->step_range_end
== 1)
3989 /* It is stepi or nexti. We always want to stop stepping after
3992 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
3993 ecs
->event_thread
->stop_step
= 1;
3994 print_stop_reason (END_STEPPING_RANGE
, 0);
3995 stop_stepping (ecs
);
3999 if (stop_pc_sal
.line
== 0)
4001 /* We have no line number information. That means to stop
4002 stepping (does this always happen right after one instruction,
4003 when we do "s" in a function with no line numbers,
4004 or can this happen as a result of a return or longjmp?). */
4006 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
4007 ecs
->event_thread
->stop_step
= 1;
4008 print_stop_reason (END_STEPPING_RANGE
, 0);
4009 stop_stepping (ecs
);
4013 /* Look for "calls" to inlined functions, part one. If the inline
4014 frame machinery detected some skipped call sites, we have entered
4015 a new inline function. */
4017 if (frame_id_eq (get_frame_id (get_current_frame ()),
4018 ecs
->event_thread
->step_frame_id
)
4019 && inline_skipped_frames (ecs
->ptid
))
4021 struct symtab_and_line call_sal
;
4024 fprintf_unfiltered (gdb_stdlog
,
4025 "infrun: stepped into inlined function\n");
4027 find_frame_sal (get_current_frame (), &call_sal
);
4029 if (ecs
->event_thread
->step_over_calls
!= STEP_OVER_ALL
)
4031 /* For "step", we're going to stop. But if the call site
4032 for this inlined function is on the same source line as
4033 we were previously stepping, go down into the function
4034 first. Otherwise stop at the call site. */
4036 if (call_sal
.line
== ecs
->event_thread
->current_line
4037 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4038 step_into_inline_frame (ecs
->ptid
);
4040 ecs
->event_thread
->stop_step
= 1;
4041 print_stop_reason (END_STEPPING_RANGE
, 0);
4042 stop_stepping (ecs
);
4047 /* For "next", we should stop at the call site if it is on a
4048 different source line. Otherwise continue through the
4049 inlined function. */
4050 if (call_sal
.line
== ecs
->event_thread
->current_line
4051 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4055 ecs
->event_thread
->stop_step
= 1;
4056 print_stop_reason (END_STEPPING_RANGE
, 0);
4057 stop_stepping (ecs
);
4063 /* Look for "calls" to inlined functions, part two. If we are still
4064 in the same real function we were stepping through, but we have
4065 to go further up to find the exact frame ID, we are stepping
4066 through a more inlined call beyond its call site. */
4068 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
4069 && !frame_id_eq (get_frame_id (get_current_frame ()),
4070 ecs
->event_thread
->step_frame_id
)
4071 && stepped_in_from (get_current_frame (),
4072 ecs
->event_thread
->step_frame_id
))
4075 fprintf_unfiltered (gdb_stdlog
,
4076 "infrun: stepping through inlined function\n");
4078 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
4082 ecs
->event_thread
->stop_step
= 1;
4083 print_stop_reason (END_STEPPING_RANGE
, 0);
4084 stop_stepping (ecs
);
4089 if ((stop_pc
== stop_pc_sal
.pc
)
4090 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
4091 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
4093 /* We are at the start of a different line. So stop. Note that
4094 we don't stop if we step into the middle of a different line.
4095 That is said to make things like for (;;) statements work
4098 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
4099 ecs
->event_thread
->stop_step
= 1;
4100 print_stop_reason (END_STEPPING_RANGE
, 0);
4101 stop_stepping (ecs
);
4105 /* We aren't done stepping.
4107 Optimize by setting the stepping range to the line.
4108 (We might not be in the original line, but if we entered a
4109 new line in mid-statement, we continue stepping. This makes
4110 things like for(;;) statements work better.) */
4112 ecs
->event_thread
->step_range_start
= stop_pc_sal
.pc
;
4113 ecs
->event_thread
->step_range_end
= stop_pc_sal
.end
;
4114 set_step_info (frame
, stop_pc_sal
);
4117 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
4121 /* Is thread TP in the middle of single-stepping? */
4124 currently_stepping (struct thread_info
*tp
)
4126 return ((tp
->step_range_end
&& tp
->step_resume_breakpoint
== NULL
)
4127 || tp
->trap_expected
4128 || tp
->stepping_through_solib_after_catch
4129 || bpstat_should_step ());
4132 /* Returns true if any thread *but* the one passed in "data" is in the
4133 middle of stepping or of handling a "next". */
4136 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
4141 return (tp
->step_range_end
4142 || tp
->trap_expected
4143 || tp
->stepping_through_solib_after_catch
);
4146 /* Inferior has stepped into a subroutine call with source code that
4147 we should not step over. Do step to the first line of code in
4151 handle_step_into_function (struct gdbarch
*gdbarch
,
4152 struct execution_control_state
*ecs
)
4155 struct symtab_and_line stop_func_sal
, sr_sal
;
4157 s
= find_pc_symtab (stop_pc
);
4158 if (s
&& s
->language
!= language_asm
)
4159 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
4160 ecs
->stop_func_start
);
4162 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4163 /* Use the step_resume_break to step until the end of the prologue,
4164 even if that involves jumps (as it seems to on the vax under
4166 /* If the prologue ends in the middle of a source line, continue to
4167 the end of that source line (if it is still within the function).
4168 Otherwise, just go to end of prologue. */
4169 if (stop_func_sal
.end
4170 && stop_func_sal
.pc
!= ecs
->stop_func_start
4171 && stop_func_sal
.end
< ecs
->stop_func_end
)
4172 ecs
->stop_func_start
= stop_func_sal
.end
;
4174 /* Architectures which require breakpoint adjustment might not be able
4175 to place a breakpoint at the computed address. If so, the test
4176 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
4177 ecs->stop_func_start to an address at which a breakpoint may be
4178 legitimately placed.
4180 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
4181 made, GDB will enter an infinite loop when stepping through
4182 optimized code consisting of VLIW instructions which contain
4183 subinstructions corresponding to different source lines. On
4184 FR-V, it's not permitted to place a breakpoint on any but the
4185 first subinstruction of a VLIW instruction. When a breakpoint is
4186 set, GDB will adjust the breakpoint address to the beginning of
4187 the VLIW instruction. Thus, we need to make the corresponding
4188 adjustment here when computing the stop address. */
4190 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
4192 ecs
->stop_func_start
4193 = gdbarch_adjust_breakpoint_address (gdbarch
,
4194 ecs
->stop_func_start
);
4197 if (ecs
->stop_func_start
== stop_pc
)
4199 /* We are already there: stop now. */
4200 ecs
->event_thread
->stop_step
= 1;
4201 print_stop_reason (END_STEPPING_RANGE
, 0);
4202 stop_stepping (ecs
);
4207 /* Put the step-breakpoint there and go until there. */
4208 init_sal (&sr_sal
); /* initialize to zeroes */
4209 sr_sal
.pc
= ecs
->stop_func_start
;
4210 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
4212 /* Do not specify what the fp should be when we stop since on
4213 some machines the prologue is where the new fp value is
4215 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
4217 /* And make sure stepping stops right away then. */
4218 ecs
->event_thread
->step_range_end
= ecs
->event_thread
->step_range_start
;
4223 /* Inferior has stepped backward into a subroutine call with source
4224 code that we should not step over. Do step to the beginning of the
4225 last line of code in it. */
4228 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
4229 struct execution_control_state
*ecs
)
4232 struct symtab_and_line stop_func_sal
, sr_sal
;
4234 s
= find_pc_symtab (stop_pc
);
4235 if (s
&& s
->language
!= language_asm
)
4236 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
4237 ecs
->stop_func_start
);
4239 stop_func_sal
= find_pc_line (stop_pc
, 0);
4241 /* OK, we're just going to keep stepping here. */
4242 if (stop_func_sal
.pc
== stop_pc
)
4244 /* We're there already. Just stop stepping now. */
4245 ecs
->event_thread
->stop_step
= 1;
4246 print_stop_reason (END_STEPPING_RANGE
, 0);
4247 stop_stepping (ecs
);
4251 /* Else just reset the step range and keep going.
4252 No step-resume breakpoint, they don't work for
4253 epilogues, which can have multiple entry paths. */
4254 ecs
->event_thread
->step_range_start
= stop_func_sal
.pc
;
4255 ecs
->event_thread
->step_range_end
= stop_func_sal
.end
;
4261 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
4262 This is used to both functions and to skip over code. */
4265 insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
4266 struct frame_id sr_id
)
4268 /* There should never be more than one step-resume or longjmp-resume
4269 breakpoint per thread, so we should never be setting a new
4270 step_resume_breakpoint when one is already active. */
4271 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
4274 fprintf_unfiltered (gdb_stdlog
,
4275 "infrun: inserting step-resume breakpoint at 0x%s\n",
4276 paddr_nz (sr_sal
.pc
));
4278 inferior_thread ()->step_resume_breakpoint
4279 = set_momentary_breakpoint (sr_sal
, sr_id
, bp_step_resume
);
4282 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
4283 to skip a potential signal handler.
4285 This is called with the interrupted function's frame. The signal
4286 handler, when it returns, will resume the interrupted function at
4290 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
4292 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
4293 struct symtab_and_line sr_sal
;
4295 gdb_assert (return_frame
!= NULL
);
4296 init_sal (&sr_sal
); /* initialize to zeros */
4298 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
4299 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4301 insert_step_resume_breakpoint_at_sal (sr_sal
, get_stack_frame_id (return_frame
));
4304 /* Similar to insert_step_resume_breakpoint_at_frame, except
4305 but a breakpoint at the previous frame's PC. This is used to
4306 skip a function after stepping into it (for "next" or if the called
4307 function has no debugging information).
4309 The current function has almost always been reached by single
4310 stepping a call or return instruction. NEXT_FRAME belongs to the
4311 current function, and the breakpoint will be set at the caller's
4314 This is a separate function rather than reusing
4315 insert_step_resume_breakpoint_at_frame in order to avoid
4316 get_prev_frame, which may stop prematurely (see the implementation
4317 of frame_unwind_caller_id for an example). */
4320 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
4322 struct gdbarch
*gdbarch
= get_frame_arch (next_frame
);
4323 struct symtab_and_line sr_sal
;
4325 /* We shouldn't have gotten here if we don't know where the call site
4327 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
4329 init_sal (&sr_sal
); /* initialize to zeros */
4331 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
4332 frame_unwind_caller_pc (next_frame
));
4333 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4335 insert_step_resume_breakpoint_at_sal (sr_sal
,
4336 frame_unwind_caller_id (next_frame
));
4339 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
4340 new breakpoint at the target of a jmp_buf. The handling of
4341 longjmp-resume uses the same mechanisms used for handling
4342 "step-resume" breakpoints. */
4345 insert_longjmp_resume_breakpoint (CORE_ADDR pc
)
4347 /* There should never be more than one step-resume or longjmp-resume
4348 breakpoint per thread, so we should never be setting a new
4349 longjmp_resume_breakpoint when one is already active. */
4350 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
4353 fprintf_unfiltered (gdb_stdlog
,
4354 "infrun: inserting longjmp-resume breakpoint at 0x%s\n",
4357 inferior_thread ()->step_resume_breakpoint
=
4358 set_momentary_breakpoint_at_pc (pc
, bp_longjmp_resume
);
4362 stop_stepping (struct execution_control_state
*ecs
)
4365 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
4367 /* Let callers know we don't want to wait for the inferior anymore. */
4368 ecs
->wait_some_more
= 0;
4371 /* This function handles various cases where we need to continue
4372 waiting for the inferior. */
4373 /* (Used to be the keep_going: label in the old wait_for_inferior) */
4376 keep_going (struct execution_control_state
*ecs
)
4378 /* Save the pc before execution, to compare with pc after stop. */
4379 ecs
->event_thread
->prev_pc
4380 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4382 /* If we did not do break;, it means we should keep running the
4383 inferior and not return to debugger. */
4385 if (ecs
->event_thread
->trap_expected
4386 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
4388 /* We took a signal (which we are supposed to pass through to
4389 the inferior, else we'd not get here) and we haven't yet
4390 gotten our trap. Simply continue. */
4391 resume (currently_stepping (ecs
->event_thread
),
4392 ecs
->event_thread
->stop_signal
);
4396 /* Either the trap was not expected, but we are continuing
4397 anyway (the user asked that this signal be passed to the
4400 The signal was SIGTRAP, e.g. it was our signal, but we
4401 decided we should resume from it.
4403 We're going to run this baby now!
4405 Note that insert_breakpoints won't try to re-insert
4406 already inserted breakpoints. Therefore, we don't
4407 care if breakpoints were already inserted, or not. */
4409 if (ecs
->event_thread
->stepping_over_breakpoint
)
4411 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
4412 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
4413 /* Since we can't do a displaced step, we have to remove
4414 the breakpoint while we step it. To keep things
4415 simple, we remove them all. */
4416 remove_breakpoints ();
4420 struct gdb_exception e
;
4421 /* Stop stepping when inserting breakpoints
4423 TRY_CATCH (e
, RETURN_MASK_ERROR
)
4425 insert_breakpoints ();
4429 stop_stepping (ecs
);
4434 ecs
->event_thread
->trap_expected
= ecs
->event_thread
->stepping_over_breakpoint
;
4436 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
4437 specifies that such a signal should be delivered to the
4440 Typically, this would occure when a user is debugging a
4441 target monitor on a simulator: the target monitor sets a
4442 breakpoint; the simulator encounters this break-point and
4443 halts the simulation handing control to GDB; GDB, noteing
4444 that the break-point isn't valid, returns control back to the
4445 simulator; the simulator then delivers the hardware
4446 equivalent of a SIGNAL_TRAP to the program being debugged. */
4448 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
4449 && !signal_program
[ecs
->event_thread
->stop_signal
])
4450 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
4452 resume (currently_stepping (ecs
->event_thread
),
4453 ecs
->event_thread
->stop_signal
);
4456 prepare_to_wait (ecs
);
4459 /* This function normally comes after a resume, before
4460 handle_inferior_event exits. It takes care of any last bits of
4461 housekeeping, and sets the all-important wait_some_more flag. */
4464 prepare_to_wait (struct execution_control_state
*ecs
)
4467 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
4468 if (infwait_state
== infwait_normal_state
)
4470 overlay_cache_invalid
= 1;
4472 /* We have to invalidate the registers BEFORE calling
4473 target_wait because they can be loaded from the target while
4474 in target_wait. This makes remote debugging a bit more
4475 efficient for those targets that provide critical registers
4476 as part of their normal status mechanism. */
4478 registers_changed ();
4479 waiton_ptid
= pid_to_ptid (-1);
4481 /* This is the old end of the while loop. Let everybody know we
4482 want to wait for the inferior some more and get called again
4484 ecs
->wait_some_more
= 1;
4487 /* Print why the inferior has stopped. We always print something when
4488 the inferior exits, or receives a signal. The rest of the cases are
4489 dealt with later on in normal_stop() and print_it_typical(). Ideally
4490 there should be a call to this function from handle_inferior_event()
4491 each time stop_stepping() is called.*/
4493 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
4495 switch (stop_reason
)
4497 case END_STEPPING_RANGE
:
4498 /* We are done with a step/next/si/ni command. */
4499 /* For now print nothing. */
4500 /* Print a message only if not in the middle of doing a "step n"
4501 operation for n > 1 */
4502 if (!inferior_thread ()->step_multi
4503 || !inferior_thread ()->stop_step
)
4504 if (ui_out_is_mi_like_p (uiout
))
4507 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
4510 /* The inferior was terminated by a signal. */
4511 annotate_signalled ();
4512 if (ui_out_is_mi_like_p (uiout
))
4515 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
4516 ui_out_text (uiout
, "\nProgram terminated with signal ");
4517 annotate_signal_name ();
4518 ui_out_field_string (uiout
, "signal-name",
4519 target_signal_to_name (stop_info
));
4520 annotate_signal_name_end ();
4521 ui_out_text (uiout
, ", ");
4522 annotate_signal_string ();
4523 ui_out_field_string (uiout
, "signal-meaning",
4524 target_signal_to_string (stop_info
));
4525 annotate_signal_string_end ();
4526 ui_out_text (uiout
, ".\n");
4527 ui_out_text (uiout
, "The program no longer exists.\n");
4530 /* The inferior program is finished. */
4531 annotate_exited (stop_info
);
4534 if (ui_out_is_mi_like_p (uiout
))
4535 ui_out_field_string (uiout
, "reason",
4536 async_reason_lookup (EXEC_ASYNC_EXITED
));
4537 ui_out_text (uiout
, "\nProgram exited with code ");
4538 ui_out_field_fmt (uiout
, "exit-code", "0%o",
4539 (unsigned int) stop_info
);
4540 ui_out_text (uiout
, ".\n");
4544 if (ui_out_is_mi_like_p (uiout
))
4547 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
4548 ui_out_text (uiout
, "\nProgram exited normally.\n");
4550 /* Support the --return-child-result option. */
4551 return_child_result_value
= stop_info
;
4553 case SIGNAL_RECEIVED
:
4554 /* Signal received. The signal table tells us to print about
4558 if (stop_info
== TARGET_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
4560 struct thread_info
*t
= inferior_thread ();
4562 ui_out_text (uiout
, "\n[");
4563 ui_out_field_string (uiout
, "thread-name",
4564 target_pid_to_str (t
->ptid
));
4565 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
4566 ui_out_text (uiout
, " stopped");
4570 ui_out_text (uiout
, "\nProgram received signal ");
4571 annotate_signal_name ();
4572 if (ui_out_is_mi_like_p (uiout
))
4574 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
4575 ui_out_field_string (uiout
, "signal-name",
4576 target_signal_to_name (stop_info
));
4577 annotate_signal_name_end ();
4578 ui_out_text (uiout
, ", ");
4579 annotate_signal_string ();
4580 ui_out_field_string (uiout
, "signal-meaning",
4581 target_signal_to_string (stop_info
));
4582 annotate_signal_string_end ();
4584 ui_out_text (uiout
, ".\n");
4587 /* Reverse execution: target ran out of history info. */
4588 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
4591 internal_error (__FILE__
, __LINE__
,
4592 _("print_stop_reason: unrecognized enum value"));
4598 /* Here to return control to GDB when the inferior stops for real.
4599 Print appropriate messages, remove breakpoints, give terminal our modes.
4601 STOP_PRINT_FRAME nonzero means print the executing frame
4602 (pc, function, args, file, line number and line text).
4603 BREAKPOINTS_FAILED nonzero means stop was due to error
4604 attempting to insert breakpoints. */
4609 struct target_waitstatus last
;
4611 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
4613 get_last_target_status (&last_ptid
, &last
);
4615 /* If an exception is thrown from this point on, make sure to
4616 propagate GDB's knowledge of the executing state to the
4617 frontend/user running state. A QUIT is an easy exception to see
4618 here, so do this before any filtered output. */
4620 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
4621 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
4622 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4623 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
4625 /* In non-stop mode, we don't want GDB to switch threads behind the
4626 user's back, to avoid races where the user is typing a command to
4627 apply to thread x, but GDB switches to thread y before the user
4628 finishes entering the command. */
4630 /* As with the notification of thread events, we want to delay
4631 notifying the user that we've switched thread context until
4632 the inferior actually stops.
4634 There's no point in saying anything if the inferior has exited.
4635 Note that SIGNALLED here means "exited with a signal", not
4636 "received a signal". */
4638 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
4639 && target_has_execution
4640 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
4641 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4643 target_terminal_ours_for_output ();
4644 printf_filtered (_("[Switching to %s]\n"),
4645 target_pid_to_str (inferior_ptid
));
4646 annotate_thread_changed ();
4647 previous_inferior_ptid
= inferior_ptid
;
4650 if (!breakpoints_always_inserted_mode () && target_has_execution
)
4652 if (remove_breakpoints ())
4654 target_terminal_ours_for_output ();
4655 printf_filtered (_("\
4656 Cannot remove breakpoints because program is no longer writable.\n\
4657 Further execution is probably impossible.\n"));
4661 /* If an auto-display called a function and that got a signal,
4662 delete that auto-display to avoid an infinite recursion. */
4664 if (stopped_by_random_signal
)
4665 disable_current_display ();
4667 /* Don't print a message if in the middle of doing a "step n"
4668 operation for n > 1 */
4669 if (target_has_execution
4670 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
4671 && last
.kind
!= TARGET_WAITKIND_EXITED
4672 && inferior_thread ()->step_multi
4673 && inferior_thread ()->stop_step
)
4676 target_terminal_ours ();
4678 /* Set the current source location. This will also happen if we
4679 display the frame below, but the current SAL will be incorrect
4680 during a user hook-stop function. */
4681 if (has_stack_frames () && !stop_stack_dummy
)
4682 set_current_sal_from_frame (get_current_frame (), 1);
4684 /* Let the user/frontend see the threads as stopped. */
4685 do_cleanups (old_chain
);
4687 /* Look up the hook_stop and run it (CLI internally handles problem
4688 of stop_command's pre-hook not existing). */
4690 catch_errors (hook_stop_stub
, stop_command
,
4691 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
4693 if (!has_stack_frames ())
4696 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
4697 || last
.kind
== TARGET_WAITKIND_EXITED
)
4700 /* Select innermost stack frame - i.e., current frame is frame 0,
4701 and current location is based on that.
4702 Don't do this on return from a stack dummy routine,
4703 or if the program has exited. */
4705 if (!stop_stack_dummy
)
4707 select_frame (get_current_frame ());
4709 /* Print current location without a level number, if
4710 we have changed functions or hit a breakpoint.
4711 Print source line if we have one.
4712 bpstat_print() contains the logic deciding in detail
4713 what to print, based on the event(s) that just occurred. */
4715 /* If --batch-silent is enabled then there's no need to print the current
4716 source location, and to try risks causing an error message about
4717 missing source files. */
4718 if (stop_print_frame
&& !batch_silent
)
4722 int do_frame_printing
= 1;
4723 struct thread_info
*tp
= inferior_thread ();
4725 bpstat_ret
= bpstat_print (tp
->stop_bpstat
);
4729 /* If we had hit a shared library event breakpoint,
4730 bpstat_print would print out this message. If we hit
4731 an OS-level shared library event, do the same
4733 if (last
.kind
== TARGET_WAITKIND_LOADED
)
4735 printf_filtered (_("Stopped due to shared library event\n"));
4736 source_flag
= SRC_LINE
; /* something bogus */
4737 do_frame_printing
= 0;
4741 /* FIXME: cagney/2002-12-01: Given that a frame ID does
4742 (or should) carry around the function and does (or
4743 should) use that when doing a frame comparison. */
4745 && frame_id_eq (tp
->step_frame_id
,
4746 get_frame_id (get_current_frame ()))
4747 && step_start_function
== find_pc_function (stop_pc
))
4748 source_flag
= SRC_LINE
; /* finished step, just print source line */
4750 source_flag
= SRC_AND_LOC
; /* print location and source line */
4752 case PRINT_SRC_AND_LOC
:
4753 source_flag
= SRC_AND_LOC
; /* print location and source line */
4755 case PRINT_SRC_ONLY
:
4756 source_flag
= SRC_LINE
;
4759 source_flag
= SRC_LINE
; /* something bogus */
4760 do_frame_printing
= 0;
4763 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
4766 /* The behavior of this routine with respect to the source
4768 SRC_LINE: Print only source line
4769 LOCATION: Print only location
4770 SRC_AND_LOC: Print location and source line */
4771 if (do_frame_printing
)
4772 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
4774 /* Display the auto-display expressions. */
4779 /* Save the function value return registers, if we care.
4780 We might be about to restore their previous contents. */
4781 if (inferior_thread ()->proceed_to_finish
)
4783 /* This should not be necessary. */
4785 regcache_xfree (stop_registers
);
4787 /* NB: The copy goes through to the target picking up the value of
4788 all the registers. */
4789 stop_registers
= regcache_dup (get_current_regcache ());
4792 if (stop_stack_dummy
)
4794 /* Pop the empty frame that contains the stack dummy.
4795 This also restores inferior state prior to the call
4796 (struct inferior_thread_state). */
4797 struct frame_info
*frame
= get_current_frame ();
4798 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
4800 /* frame_pop() calls reinit_frame_cache as the last thing it does
4801 which means there's currently no selected frame. We don't need
4802 to re-establish a selected frame if the dummy call returns normally,
4803 that will be done by restore_inferior_status. However, we do have
4804 to handle the case where the dummy call is returning after being
4805 stopped (e.g. the dummy call previously hit a breakpoint). We
4806 can't know which case we have so just always re-establish a
4807 selected frame here. */
4808 select_frame (get_current_frame ());
4812 annotate_stopped ();
4814 /* Suppress the stop observer if we're in the middle of:
4816 - a step n (n > 1), as there still more steps to be done.
4818 - a "finish" command, as the observer will be called in
4819 finish_command_continuation, so it can include the inferior
4820 function's return value.
4822 - calling an inferior function, as we pretend we inferior didn't
4823 run at all. The return value of the call is handled by the
4824 expression evaluator, through call_function_by_hand. */
4826 if (!target_has_execution
4827 || last
.kind
== TARGET_WAITKIND_SIGNALLED
4828 || last
.kind
== TARGET_WAITKIND_EXITED
4829 || (!inferior_thread ()->step_multi
4830 && !(inferior_thread ()->stop_bpstat
4831 && inferior_thread ()->proceed_to_finish
)
4832 && !inferior_thread ()->in_infcall
))
4834 if (!ptid_equal (inferior_ptid
, null_ptid
))
4835 observer_notify_normal_stop (inferior_thread ()->stop_bpstat
,
4838 observer_notify_normal_stop (NULL
, stop_print_frame
);
4841 if (target_has_execution
)
4843 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
4844 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4845 /* Delete the breakpoint we stopped at, if it wants to be deleted.
4846 Delete any breakpoint that is to be deleted at the next stop. */
4847 breakpoint_auto_delete (inferior_thread ()->stop_bpstat
);
4852 hook_stop_stub (void *cmd
)
4854 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
4859 signal_stop_state (int signo
)
4861 return signal_stop
[signo
];
4865 signal_print_state (int signo
)
4867 return signal_print
[signo
];
4871 signal_pass_state (int signo
)
4873 return signal_program
[signo
];
4877 signal_stop_update (int signo
, int state
)
4879 int ret
= signal_stop
[signo
];
4880 signal_stop
[signo
] = state
;
4885 signal_print_update (int signo
, int state
)
4887 int ret
= signal_print
[signo
];
4888 signal_print
[signo
] = state
;
4893 signal_pass_update (int signo
, int state
)
4895 int ret
= signal_program
[signo
];
4896 signal_program
[signo
] = state
;
4901 sig_print_header (void)
4903 printf_filtered (_("\
4904 Signal Stop\tPrint\tPass to program\tDescription\n"));
4908 sig_print_info (enum target_signal oursig
)
4910 const char *name
= target_signal_to_name (oursig
);
4911 int name_padding
= 13 - strlen (name
);
4913 if (name_padding
<= 0)
4916 printf_filtered ("%s", name
);
4917 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
4918 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
4919 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
4920 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
4921 printf_filtered ("%s\n", target_signal_to_string (oursig
));
4924 /* Specify how various signals in the inferior should be handled. */
4927 handle_command (char *args
, int from_tty
)
4930 int digits
, wordlen
;
4931 int sigfirst
, signum
, siglast
;
4932 enum target_signal oursig
;
4935 unsigned char *sigs
;
4936 struct cleanup
*old_chain
;
4940 error_no_arg (_("signal to handle"));
4943 /* Allocate and zero an array of flags for which signals to handle. */
4945 nsigs
= (int) TARGET_SIGNAL_LAST
;
4946 sigs
= (unsigned char *) alloca (nsigs
);
4947 memset (sigs
, 0, nsigs
);
4949 /* Break the command line up into args. */
4951 argv
= gdb_buildargv (args
);
4952 old_chain
= make_cleanup_freeargv (argv
);
4954 /* Walk through the args, looking for signal oursigs, signal names, and
4955 actions. Signal numbers and signal names may be interspersed with
4956 actions, with the actions being performed for all signals cumulatively
4957 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
4959 while (*argv
!= NULL
)
4961 wordlen
= strlen (*argv
);
4962 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
4966 sigfirst
= siglast
= -1;
4968 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
4970 /* Apply action to all signals except those used by the
4971 debugger. Silently skip those. */
4974 siglast
= nsigs
- 1;
4976 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
4978 SET_SIGS (nsigs
, sigs
, signal_stop
);
4979 SET_SIGS (nsigs
, sigs
, signal_print
);
4981 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
4983 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4985 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
4987 SET_SIGS (nsigs
, sigs
, signal_print
);
4989 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
4991 SET_SIGS (nsigs
, sigs
, signal_program
);
4993 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
4995 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4997 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
4999 SET_SIGS (nsigs
, sigs
, signal_program
);
5001 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
5003 UNSET_SIGS (nsigs
, sigs
, signal_print
);
5004 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
5006 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
5008 UNSET_SIGS (nsigs
, sigs
, signal_program
);
5010 else if (digits
> 0)
5012 /* It is numeric. The numeric signal refers to our own
5013 internal signal numbering from target.h, not to host/target
5014 signal number. This is a feature; users really should be
5015 using symbolic names anyway, and the common ones like
5016 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
5018 sigfirst
= siglast
= (int)
5019 target_signal_from_command (atoi (*argv
));
5020 if ((*argv
)[digits
] == '-')
5023 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
5025 if (sigfirst
> siglast
)
5027 /* Bet he didn't figure we'd think of this case... */
5035 oursig
= target_signal_from_name (*argv
);
5036 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
5038 sigfirst
= siglast
= (int) oursig
;
5042 /* Not a number and not a recognized flag word => complain. */
5043 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
5047 /* If any signal numbers or symbol names were found, set flags for
5048 which signals to apply actions to. */
5050 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
5052 switch ((enum target_signal
) signum
)
5054 case TARGET_SIGNAL_TRAP
:
5055 case TARGET_SIGNAL_INT
:
5056 if (!allsigs
&& !sigs
[signum
])
5058 if (query (_("%s is used by the debugger.\n\
5059 Are you sure you want to change it? "), target_signal_to_name ((enum target_signal
) signum
)))
5065 printf_unfiltered (_("Not confirmed, unchanged.\n"));
5066 gdb_flush (gdb_stdout
);
5070 case TARGET_SIGNAL_0
:
5071 case TARGET_SIGNAL_DEFAULT
:
5072 case TARGET_SIGNAL_UNKNOWN
:
5073 /* Make sure that "all" doesn't print these. */
5084 for (signum
= 0; signum
< nsigs
; signum
++)
5087 target_notice_signals (inferior_ptid
);
5091 /* Show the results. */
5092 sig_print_header ();
5093 for (; signum
< nsigs
; signum
++)
5095 sig_print_info (signum
);
5101 do_cleanups (old_chain
);
5105 xdb_handle_command (char *args
, int from_tty
)
5108 struct cleanup
*old_chain
;
5111 error_no_arg (_("xdb command"));
5113 /* Break the command line up into args. */
5115 argv
= gdb_buildargv (args
);
5116 old_chain
= make_cleanup_freeargv (argv
);
5117 if (argv
[1] != (char *) NULL
)
5122 bufLen
= strlen (argv
[0]) + 20;
5123 argBuf
= (char *) xmalloc (bufLen
);
5127 enum target_signal oursig
;
5129 oursig
= target_signal_from_name (argv
[0]);
5130 memset (argBuf
, 0, bufLen
);
5131 if (strcmp (argv
[1], "Q") == 0)
5132 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
5135 if (strcmp (argv
[1], "s") == 0)
5137 if (!signal_stop
[oursig
])
5138 sprintf (argBuf
, "%s %s", argv
[0], "stop");
5140 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
5142 else if (strcmp (argv
[1], "i") == 0)
5144 if (!signal_program
[oursig
])
5145 sprintf (argBuf
, "%s %s", argv
[0], "pass");
5147 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
5149 else if (strcmp (argv
[1], "r") == 0)
5151 if (!signal_print
[oursig
])
5152 sprintf (argBuf
, "%s %s", argv
[0], "print");
5154 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
5160 handle_command (argBuf
, from_tty
);
5162 printf_filtered (_("Invalid signal handling flag.\n"));
5167 do_cleanups (old_chain
);
5170 /* Print current contents of the tables set by the handle command.
5171 It is possible we should just be printing signals actually used
5172 by the current target (but for things to work right when switching
5173 targets, all signals should be in the signal tables). */
5176 signals_info (char *signum_exp
, int from_tty
)
5178 enum target_signal oursig
;
5179 sig_print_header ();
5183 /* First see if this is a symbol name. */
5184 oursig
= target_signal_from_name (signum_exp
);
5185 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
5187 /* No, try numeric. */
5189 target_signal_from_command (parse_and_eval_long (signum_exp
));
5191 sig_print_info (oursig
);
5195 printf_filtered ("\n");
5196 /* These ugly casts brought to you by the native VAX compiler. */
5197 for (oursig
= TARGET_SIGNAL_FIRST
;
5198 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
5199 oursig
= (enum target_signal
) ((int) oursig
+ 1))
5203 if (oursig
!= TARGET_SIGNAL_UNKNOWN
5204 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
5205 sig_print_info (oursig
);
5208 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
5211 /* The $_siginfo convenience variable is a bit special. We don't know
5212 for sure the type of the value until we actually have a chance to
5213 fetch the data. The type can change depending on gdbarch, so it it
5214 also dependent on which thread you have selected.
5216 1. making $_siginfo be an internalvar that creates a new value on
5219 2. making the value of $_siginfo be an lval_computed value. */
5221 /* This function implements the lval_computed support for reading a
5225 siginfo_value_read (struct value
*v
)
5227 LONGEST transferred
;
5230 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
5232 value_contents_all_raw (v
),
5234 TYPE_LENGTH (value_type (v
)));
5236 if (transferred
!= TYPE_LENGTH (value_type (v
)))
5237 error (_("Unable to read siginfo"));
5240 /* This function implements the lval_computed support for writing a
5244 siginfo_value_write (struct value
*v
, struct value
*fromval
)
5246 LONGEST transferred
;
5248 transferred
= target_write (¤t_target
,
5249 TARGET_OBJECT_SIGNAL_INFO
,
5251 value_contents_all_raw (fromval
),
5253 TYPE_LENGTH (value_type (fromval
)));
5255 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
5256 error (_("Unable to write siginfo"));
5259 static struct lval_funcs siginfo_value_funcs
=
5265 /* Return a new value with the correct type for the siginfo object of
5266 the current thread using architecture GDBARCH. Return a void value
5267 if there's no object available. */
5269 static struct value
*
5270 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
)
5272 if (target_has_stack
5273 && !ptid_equal (inferior_ptid
, null_ptid
)
5274 && gdbarch_get_siginfo_type_p (gdbarch
))
5276 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
5277 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
5280 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
5284 /* Inferior thread state.
5285 These are details related to the inferior itself, and don't include
5286 things like what frame the user had selected or what gdb was doing
5287 with the target at the time.
5288 For inferior function calls these are things we want to restore
5289 regardless of whether the function call successfully completes
5290 or the dummy frame has to be manually popped. */
5292 struct inferior_thread_state
5294 enum target_signal stop_signal
;
5296 struct regcache
*registers
;
5299 struct inferior_thread_state
*
5300 save_inferior_thread_state (void)
5302 struct inferior_thread_state
*inf_state
= XMALLOC (struct inferior_thread_state
);
5303 struct thread_info
*tp
= inferior_thread ();
5305 inf_state
->stop_signal
= tp
->stop_signal
;
5306 inf_state
->stop_pc
= stop_pc
;
5308 inf_state
->registers
= regcache_dup (get_current_regcache ());
5313 /* Restore inferior session state to INF_STATE. */
5316 restore_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5318 struct thread_info
*tp
= inferior_thread ();
5320 tp
->stop_signal
= inf_state
->stop_signal
;
5321 stop_pc
= inf_state
->stop_pc
;
5323 /* The inferior can be gone if the user types "print exit(0)"
5324 (and perhaps other times). */
5325 if (target_has_execution
)
5326 /* NB: The register write goes through to the target. */
5327 regcache_cpy (get_current_regcache (), inf_state
->registers
);
5328 regcache_xfree (inf_state
->registers
);
5333 do_restore_inferior_thread_state_cleanup (void *state
)
5335 restore_inferior_thread_state (state
);
5339 make_cleanup_restore_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5341 return make_cleanup (do_restore_inferior_thread_state_cleanup
, inf_state
);
5345 discard_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5347 regcache_xfree (inf_state
->registers
);
5352 get_inferior_thread_state_regcache (struct inferior_thread_state
*inf_state
)
5354 return inf_state
->registers
;
5357 /* Session related state for inferior function calls.
5358 These are the additional bits of state that need to be restored
5359 when an inferior function call successfully completes. */
5361 struct inferior_status
5365 int stop_stack_dummy
;
5366 int stopped_by_random_signal
;
5367 int stepping_over_breakpoint
;
5368 CORE_ADDR step_range_start
;
5369 CORE_ADDR step_range_end
;
5370 struct frame_id step_frame_id
;
5371 struct frame_id step_stack_frame_id
;
5372 enum step_over_calls_kind step_over_calls
;
5373 CORE_ADDR step_resume_break_address
;
5374 int stop_after_trap
;
5377 /* ID if the selected frame when the inferior function call was made. */
5378 struct frame_id selected_frame_id
;
5380 int proceed_to_finish
;
5384 /* Save all of the information associated with the inferior<==>gdb
5387 struct inferior_status
*
5388 save_inferior_status (void)
5390 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
5391 struct thread_info
*tp
= inferior_thread ();
5392 struct inferior
*inf
= current_inferior ();
5394 inf_status
->stop_step
= tp
->stop_step
;
5395 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
5396 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
5397 inf_status
->stepping_over_breakpoint
= tp
->trap_expected
;
5398 inf_status
->step_range_start
= tp
->step_range_start
;
5399 inf_status
->step_range_end
= tp
->step_range_end
;
5400 inf_status
->step_frame_id
= tp
->step_frame_id
;
5401 inf_status
->step_stack_frame_id
= tp
->step_stack_frame_id
;
5402 inf_status
->step_over_calls
= tp
->step_over_calls
;
5403 inf_status
->stop_after_trap
= stop_after_trap
;
5404 inf_status
->stop_soon
= inf
->stop_soon
;
5405 /* Save original bpstat chain here; replace it with copy of chain.
5406 If caller's caller is walking the chain, they'll be happier if we
5407 hand them back the original chain when restore_inferior_status is
5409 inf_status
->stop_bpstat
= tp
->stop_bpstat
;
5410 tp
->stop_bpstat
= bpstat_copy (tp
->stop_bpstat
);
5411 inf_status
->proceed_to_finish
= tp
->proceed_to_finish
;
5412 inf_status
->in_infcall
= tp
->in_infcall
;
5414 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
5420 restore_selected_frame (void *args
)
5422 struct frame_id
*fid
= (struct frame_id
*) args
;
5423 struct frame_info
*frame
;
5425 frame
= frame_find_by_id (*fid
);
5427 /* If inf_status->selected_frame_id is NULL, there was no previously
5431 warning (_("Unable to restore previously selected frame."));
5435 select_frame (frame
);
5440 /* Restore inferior session state to INF_STATUS. */
5443 restore_inferior_status (struct inferior_status
*inf_status
)
5445 struct thread_info
*tp
= inferior_thread ();
5446 struct inferior
*inf
= current_inferior ();
5448 tp
->stop_step
= inf_status
->stop_step
;
5449 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
5450 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
5451 tp
->trap_expected
= inf_status
->stepping_over_breakpoint
;
5452 tp
->step_range_start
= inf_status
->step_range_start
;
5453 tp
->step_range_end
= inf_status
->step_range_end
;
5454 tp
->step_frame_id
= inf_status
->step_frame_id
;
5455 tp
->step_stack_frame_id
= inf_status
->step_stack_frame_id
;
5456 tp
->step_over_calls
= inf_status
->step_over_calls
;
5457 stop_after_trap
= inf_status
->stop_after_trap
;
5458 inf
->stop_soon
= inf_status
->stop_soon
;
5459 bpstat_clear (&tp
->stop_bpstat
);
5460 tp
->stop_bpstat
= inf_status
->stop_bpstat
;
5461 inf_status
->stop_bpstat
= NULL
;
5462 tp
->proceed_to_finish
= inf_status
->proceed_to_finish
;
5463 tp
->in_infcall
= inf_status
->in_infcall
;
5465 if (target_has_stack
)
5467 /* The point of catch_errors is that if the stack is clobbered,
5468 walking the stack might encounter a garbage pointer and
5469 error() trying to dereference it. */
5471 (restore_selected_frame
, &inf_status
->selected_frame_id
,
5472 "Unable to restore previously selected frame:\n",
5473 RETURN_MASK_ERROR
) == 0)
5474 /* Error in restoring the selected frame. Select the innermost
5476 select_frame (get_current_frame ());
5483 do_restore_inferior_status_cleanup (void *sts
)
5485 restore_inferior_status (sts
);
5489 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
5491 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
5495 discard_inferior_status (struct inferior_status
*inf_status
)
5497 /* See save_inferior_status for info on stop_bpstat. */
5498 bpstat_clear (&inf_status
->stop_bpstat
);
5503 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
5505 struct target_waitstatus last
;
5508 get_last_target_status (&last_ptid
, &last
);
5510 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
5513 if (!ptid_equal (last_ptid
, pid
))
5516 *child_pid
= last
.value
.related_pid
;
5521 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
5523 struct target_waitstatus last
;
5526 get_last_target_status (&last_ptid
, &last
);
5528 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
5531 if (!ptid_equal (last_ptid
, pid
))
5534 *child_pid
= last
.value
.related_pid
;
5539 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
5541 struct target_waitstatus last
;
5544 get_last_target_status (&last_ptid
, &last
);
5546 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
5549 if (!ptid_equal (last_ptid
, pid
))
5552 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
5556 /* Oft used ptids */
5558 ptid_t minus_one_ptid
;
5560 /* Create a ptid given the necessary PID, LWP, and TID components. */
5563 ptid_build (int pid
, long lwp
, long tid
)
5573 /* Create a ptid from just a pid. */
5576 pid_to_ptid (int pid
)
5578 return ptid_build (pid
, 0, 0);
5581 /* Fetch the pid (process id) component from a ptid. */
5584 ptid_get_pid (ptid_t ptid
)
5589 /* Fetch the lwp (lightweight process) component from a ptid. */
5592 ptid_get_lwp (ptid_t ptid
)
5597 /* Fetch the tid (thread id) component from a ptid. */
5600 ptid_get_tid (ptid_t ptid
)
5605 /* ptid_equal() is used to test equality of two ptids. */
5608 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
5610 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
5611 && ptid1
.tid
== ptid2
.tid
);
5614 /* Returns true if PTID represents a process. */
5617 ptid_is_pid (ptid_t ptid
)
5619 if (ptid_equal (minus_one_ptid
, ptid
))
5621 if (ptid_equal (null_ptid
, ptid
))
5624 return (ptid_get_lwp (ptid
) == 0 && ptid_get_tid (ptid
) == 0);
5627 /* restore_inferior_ptid() will be used by the cleanup machinery
5628 to restore the inferior_ptid value saved in a call to
5629 save_inferior_ptid(). */
5632 restore_inferior_ptid (void *arg
)
5634 ptid_t
*saved_ptid_ptr
= arg
;
5635 inferior_ptid
= *saved_ptid_ptr
;
5639 /* Save the value of inferior_ptid so that it may be restored by a
5640 later call to do_cleanups(). Returns the struct cleanup pointer
5641 needed for later doing the cleanup. */
5644 save_inferior_ptid (void)
5646 ptid_t
*saved_ptid_ptr
;
5648 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
5649 *saved_ptid_ptr
= inferior_ptid
;
5650 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
5654 /* User interface for reverse debugging:
5655 Set exec-direction / show exec-direction commands
5656 (returns error unless target implements to_set_exec_direction method). */
5658 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
5659 static const char exec_forward
[] = "forward";
5660 static const char exec_reverse
[] = "reverse";
5661 static const char *exec_direction
= exec_forward
;
5662 static const char *exec_direction_names
[] = {
5669 set_exec_direction_func (char *args
, int from_tty
,
5670 struct cmd_list_element
*cmd
)
5672 if (target_can_execute_reverse
)
5674 if (!strcmp (exec_direction
, exec_forward
))
5675 execution_direction
= EXEC_FORWARD
;
5676 else if (!strcmp (exec_direction
, exec_reverse
))
5677 execution_direction
= EXEC_REVERSE
;
5682 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
5683 struct cmd_list_element
*cmd
, const char *value
)
5685 switch (execution_direction
) {
5687 fprintf_filtered (out
, _("Forward.\n"));
5690 fprintf_filtered (out
, _("Reverse.\n"));
5694 fprintf_filtered (out
,
5695 _("Forward (target `%s' does not support exec-direction).\n"),
5701 /* User interface for non-stop mode. */
5704 static int non_stop_1
= 0;
5707 set_non_stop (char *args
, int from_tty
,
5708 struct cmd_list_element
*c
)
5710 if (target_has_execution
)
5712 non_stop_1
= non_stop
;
5713 error (_("Cannot change this setting while the inferior is running."));
5716 non_stop
= non_stop_1
;
5720 show_non_stop (struct ui_file
*file
, int from_tty
,
5721 struct cmd_list_element
*c
, const char *value
)
5723 fprintf_filtered (file
,
5724 _("Controlling the inferior in non-stop mode is %s.\n"),
5729 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
5730 struct cmd_list_element
*c
, const char *value
)
5732 fprintf_filtered (file
, _("\
5733 Resuming the execution of threads of all processes is %s.\n"), value
);
5737 _initialize_infrun (void)
5741 struct cmd_list_element
*c
;
5743 add_info ("signals", signals_info
, _("\
5744 What debugger does when program gets various signals.\n\
5745 Specify a signal as argument to print info on that signal only."));
5746 add_info_alias ("handle", "signals", 0);
5748 add_com ("handle", class_run
, handle_command
, _("\
5749 Specify how to handle a signal.\n\
5750 Args are signals and actions to apply to those signals.\n\
5751 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
5752 from 1-15 are allowed for compatibility with old versions of GDB.\n\
5753 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
5754 The special arg \"all\" is recognized to mean all signals except those\n\
5755 used by the debugger, typically SIGTRAP and SIGINT.\n\
5756 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
5757 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
5758 Stop means reenter debugger if this signal happens (implies print).\n\
5759 Print means print a message if this signal happens.\n\
5760 Pass means let program see this signal; otherwise program doesn't know.\n\
5761 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
5762 Pass and Stop may be combined."));
5765 add_com ("lz", class_info
, signals_info
, _("\
5766 What debugger does when program gets various signals.\n\
5767 Specify a signal as argument to print info on that signal only."));
5768 add_com ("z", class_run
, xdb_handle_command
, _("\
5769 Specify how to handle a signal.\n\
5770 Args are signals and actions to apply to those signals.\n\
5771 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
5772 from 1-15 are allowed for compatibility with old versions of GDB.\n\
5773 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
5774 The special arg \"all\" is recognized to mean all signals except those\n\
5775 used by the debugger, typically SIGTRAP and SIGINT.\n\
5776 Recognized actions include \"s\" (toggles between stop and nostop), \n\
5777 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
5778 nopass), \"Q\" (noprint)\n\
5779 Stop means reenter debugger if this signal happens (implies print).\n\
5780 Print means print a message if this signal happens.\n\
5781 Pass means let program see this signal; otherwise program doesn't know.\n\
5782 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
5783 Pass and Stop may be combined."));
5787 stop_command
= add_cmd ("stop", class_obscure
,
5788 not_just_help_class_command
, _("\
5789 There is no `stop' command, but you can set a hook on `stop'.\n\
5790 This allows you to set a list of commands to be run each time execution\n\
5791 of the program stops."), &cmdlist
);
5793 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
5794 Set inferior debugging."), _("\
5795 Show inferior debugging."), _("\
5796 When non-zero, inferior specific debugging is enabled."),
5799 &setdebuglist
, &showdebuglist
);
5801 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
5802 Set displaced stepping debugging."), _("\
5803 Show displaced stepping debugging."), _("\
5804 When non-zero, displaced stepping specific debugging is enabled."),
5806 show_debug_displaced
,
5807 &setdebuglist
, &showdebuglist
);
5809 add_setshow_boolean_cmd ("non-stop", no_class
,
5811 Set whether gdb controls the inferior in non-stop mode."), _("\
5812 Show whether gdb controls the inferior in non-stop mode."), _("\
5813 When debugging a multi-threaded program and this setting is\n\
5814 off (the default, also called all-stop mode), when one thread stops\n\
5815 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
5816 all other threads in the program while you interact with the thread of\n\
5817 interest. When you continue or step a thread, you can allow the other\n\
5818 threads to run, or have them remain stopped, but while you inspect any\n\
5819 thread's state, all threads stop.\n\
5821 In non-stop mode, when one thread stops, other threads can continue\n\
5822 to run freely. You'll be able to step each thread independently,\n\
5823 leave it stopped or free to run as needed."),
5829 numsigs
= (int) TARGET_SIGNAL_LAST
;
5830 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
5831 signal_print
= (unsigned char *)
5832 xmalloc (sizeof (signal_print
[0]) * numsigs
);
5833 signal_program
= (unsigned char *)
5834 xmalloc (sizeof (signal_program
[0]) * numsigs
);
5835 for (i
= 0; i
< numsigs
; i
++)
5838 signal_print
[i
] = 1;
5839 signal_program
[i
] = 1;
5842 /* Signals caused by debugger's own actions
5843 should not be given to the program afterwards. */
5844 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
5845 signal_program
[TARGET_SIGNAL_INT
] = 0;
5847 /* Signals that are not errors should not normally enter the debugger. */
5848 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
5849 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
5850 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
5851 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
5852 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
5853 signal_print
[TARGET_SIGNAL_PROF
] = 0;
5854 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
5855 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
5856 signal_stop
[TARGET_SIGNAL_IO
] = 0;
5857 signal_print
[TARGET_SIGNAL_IO
] = 0;
5858 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
5859 signal_print
[TARGET_SIGNAL_POLL
] = 0;
5860 signal_stop
[TARGET_SIGNAL_URG
] = 0;
5861 signal_print
[TARGET_SIGNAL_URG
] = 0;
5862 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
5863 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
5865 /* These signals are used internally by user-level thread
5866 implementations. (See signal(5) on Solaris.) Like the above
5867 signals, a healthy program receives and handles them as part of
5868 its normal operation. */
5869 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
5870 signal_print
[TARGET_SIGNAL_LWP
] = 0;
5871 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
5872 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
5873 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
5874 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
5876 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
5877 &stop_on_solib_events
, _("\
5878 Set stopping for shared library events."), _("\
5879 Show stopping for shared library events."), _("\
5880 If nonzero, gdb will give control to the user when the dynamic linker\n\
5881 notifies gdb of shared library events. The most common event of interest\n\
5882 to the user would be loading/unloading of a new library."),
5884 show_stop_on_solib_events
,
5885 &setlist
, &showlist
);
5887 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
5888 follow_fork_mode_kind_names
,
5889 &follow_fork_mode_string
, _("\
5890 Set debugger response to a program call of fork or vfork."), _("\
5891 Show debugger response to a program call of fork or vfork."), _("\
5892 A fork or vfork creates a new process. follow-fork-mode can be:\n\
5893 parent - the original process is debugged after a fork\n\
5894 child - the new process is debugged after a fork\n\
5895 The unfollowed process will continue to run.\n\
5896 By default, the debugger will follow the parent process."),
5898 show_follow_fork_mode_string
,
5899 &setlist
, &showlist
);
5901 add_setshow_enum_cmd ("scheduler-locking", class_run
,
5902 scheduler_enums
, &scheduler_mode
, _("\
5903 Set mode for locking scheduler during execution."), _("\
5904 Show mode for locking scheduler during execution."), _("\
5905 off == no locking (threads may preempt at any time)\n\
5906 on == full locking (no thread except the current thread may run)\n\
5907 step == scheduler locked during every single-step operation.\n\
5908 In this mode, no other thread may run during a step command.\n\
5909 Other threads may run while stepping over a function call ('next')."),
5910 set_schedlock_func
, /* traps on target vector */
5911 show_scheduler_mode
,
5912 &setlist
, &showlist
);
5914 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
5915 Set mode for resuming threads of all processes."), _("\
5916 Show mode for resuming threads of all processes."), _("\
5917 When on, execution commands (such as 'continue' or 'next') resume all\n\
5918 threads of all processes. When off (which is the default), execution\n\
5919 commands only resume the threads of the current process. The set of\n\
5920 threads that are resumed is further refined by the scheduler-locking\n\
5921 mode (see help set scheduler-locking)."),
5923 show_schedule_multiple
,
5924 &setlist
, &showlist
);
5926 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
5927 Set mode of the step operation."), _("\
5928 Show mode of the step operation."), _("\
5929 When set, doing a step over a function without debug line information\n\
5930 will stop at the first instruction of that function. Otherwise, the\n\
5931 function is skipped and the step command stops at a different source line."),
5933 show_step_stop_if_no_debug
,
5934 &setlist
, &showlist
);
5936 add_setshow_enum_cmd ("displaced-stepping", class_run
,
5937 can_use_displaced_stepping_enum
,
5938 &can_use_displaced_stepping
, _("\
5939 Set debugger's willingness to use displaced stepping."), _("\
5940 Show debugger's willingness to use displaced stepping."), _("\
5941 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
5942 supported by the target architecture. If off, gdb will not use displaced\n\
5943 stepping to step over breakpoints, even if such is supported by the target\n\
5944 architecture. If auto (which is the default), gdb will use displaced stepping\n\
5945 if the target architecture supports it and non-stop mode is active, but will not\n\
5946 use it in all-stop mode (see help set non-stop)."),
5948 show_can_use_displaced_stepping
,
5949 &setlist
, &showlist
);
5951 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
5952 &exec_direction
, _("Set direction of execution.\n\
5953 Options are 'forward' or 'reverse'."),
5954 _("Show direction of execution (forward/reverse)."),
5955 _("Tells gdb whether to execute forward or backward."),
5956 set_exec_direction_func
, show_exec_direction_func
,
5957 &setlist
, &showlist
);
5959 /* ptid initializations */
5960 null_ptid
= ptid_build (0, 0, 0);
5961 minus_one_ptid
= ptid_build (-1, 0, 0);
5962 inferior_ptid
= null_ptid
;
5963 target_last_wait_ptid
= minus_one_ptid
;
5964 displaced_step_ptid
= null_ptid
;
5966 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
5967 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
5968 observer_attach_thread_exit (infrun_thread_thread_exit
);
5970 /* Explicitly create without lookup, since that tries to create a
5971 value with a void typed value, and when we get here, gdbarch
5972 isn't initialized yet. At this point, we're quite sure there
5973 isn't another convenience variable of the same name. */
5974 create_internalvar_type_lazy ("_siginfo", siginfo_make_value
);