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 gdbarch
*gdbarch
,
1763 struct symtab_and_line sr_sal
,
1764 struct frame_id sr_id
);
1765 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
1767 static void stop_stepping (struct execution_control_state
*ecs
);
1768 static void prepare_to_wait (struct execution_control_state
*ecs
);
1769 static void keep_going (struct execution_control_state
*ecs
);
1770 static void print_stop_reason (enum inferior_stop_reason stop_reason
,
1773 /* Callback for iterate over threads. If the thread is stopped, but
1774 the user/frontend doesn't know about that yet, go through
1775 normal_stop, as if the thread had just stopped now. ARG points at
1776 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
1777 ptid_is_pid(PTID) is true, applies to all threads of the process
1778 pointed at by PTID. Otherwise, apply only to the thread pointed by
1782 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
1784 ptid_t ptid
= * (ptid_t
*) arg
;
1786 if ((ptid_equal (info
->ptid
, ptid
)
1787 || ptid_equal (minus_one_ptid
, ptid
)
1788 || (ptid_is_pid (ptid
)
1789 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
1790 && is_running (info
->ptid
)
1791 && !is_executing (info
->ptid
))
1793 struct cleanup
*old_chain
;
1794 struct execution_control_state ecss
;
1795 struct execution_control_state
*ecs
= &ecss
;
1797 memset (ecs
, 0, sizeof (*ecs
));
1799 old_chain
= make_cleanup_restore_current_thread ();
1801 switch_to_thread (info
->ptid
);
1803 /* Go through handle_inferior_event/normal_stop, so we always
1804 have consistent output as if the stop event had been
1806 ecs
->ptid
= info
->ptid
;
1807 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
1808 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
1809 ecs
->ws
.value
.sig
= TARGET_SIGNAL_0
;
1811 handle_inferior_event (ecs
);
1813 if (!ecs
->wait_some_more
)
1815 struct thread_info
*tp
;
1819 /* Finish off the continuations. The continations
1820 themselves are responsible for realising the thread
1821 didn't finish what it was supposed to do. */
1822 tp
= inferior_thread ();
1823 do_all_intermediate_continuations_thread (tp
);
1824 do_all_continuations_thread (tp
);
1827 do_cleanups (old_chain
);
1833 /* This function is attached as a "thread_stop_requested" observer.
1834 Cleanup local state that assumed the PTID was to be resumed, and
1835 report the stop to the frontend. */
1838 infrun_thread_stop_requested (ptid_t ptid
)
1840 struct displaced_step_request
*it
, *next
, *prev
= NULL
;
1842 /* PTID was requested to stop. Remove it from the displaced
1843 stepping queue, so we don't try to resume it automatically. */
1844 for (it
= displaced_step_request_queue
; it
; it
= next
)
1848 if (ptid_equal (it
->ptid
, ptid
)
1849 || ptid_equal (minus_one_ptid
, ptid
)
1850 || (ptid_is_pid (ptid
)
1851 && ptid_get_pid (ptid
) == ptid_get_pid (it
->ptid
)))
1853 if (displaced_step_request_queue
== it
)
1854 displaced_step_request_queue
= it
->next
;
1856 prev
->next
= it
->next
;
1864 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
1868 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
1870 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
1871 nullify_last_target_wait_ptid ();
1874 /* Callback for iterate_over_threads. */
1877 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
1879 if (is_exited (info
->ptid
))
1882 delete_step_resume_breakpoint (info
);
1886 /* In all-stop, delete the step resume breakpoint of any thread that
1887 had one. In non-stop, delete the step resume breakpoint of the
1888 thread that just stopped. */
1891 delete_step_thread_step_resume_breakpoint (void)
1893 if (!target_has_execution
1894 || ptid_equal (inferior_ptid
, null_ptid
))
1895 /* If the inferior has exited, we have already deleted the step
1896 resume breakpoints out of GDB's lists. */
1901 /* If in non-stop mode, only delete the step-resume or
1902 longjmp-resume breakpoint of the thread that just stopped
1904 struct thread_info
*tp
= inferior_thread ();
1905 delete_step_resume_breakpoint (tp
);
1908 /* In all-stop mode, delete all step-resume and longjmp-resume
1909 breakpoints of any thread that had them. */
1910 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
1913 /* A cleanup wrapper. */
1916 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
1918 delete_step_thread_step_resume_breakpoint ();
1921 /* Pretty print the results of target_wait, for debugging purposes. */
1924 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
1925 const struct target_waitstatus
*ws
)
1927 char *status_string
= target_waitstatus_to_string (ws
);
1928 struct ui_file
*tmp_stream
= mem_fileopen ();
1932 /* The text is split over several lines because it was getting too long.
1933 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
1934 output as a unit; we want only one timestamp printed if debug_timestamp
1937 fprintf_unfiltered (tmp_stream
,
1938 "infrun: target_wait (%d", PIDGET (waiton_ptid
));
1939 if (PIDGET (waiton_ptid
) != -1)
1940 fprintf_unfiltered (tmp_stream
,
1941 " [%s]", target_pid_to_str (waiton_ptid
));
1942 fprintf_unfiltered (tmp_stream
, ", status) =\n");
1943 fprintf_unfiltered (tmp_stream
,
1944 "infrun: %d [%s],\n",
1945 PIDGET (result_ptid
), target_pid_to_str (result_ptid
));
1946 fprintf_unfiltered (tmp_stream
,
1950 text
= ui_file_xstrdup (tmp_stream
, &len
);
1952 /* This uses %s in part to handle %'s in the text, but also to avoid
1953 a gcc error: the format attribute requires a string literal. */
1954 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
1956 xfree (status_string
);
1958 ui_file_delete (tmp_stream
);
1961 /* Wait for control to return from inferior to debugger.
1963 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
1964 as if they were SIGTRAP signals. This can be useful during
1965 the startup sequence on some targets such as HP/UX, where
1966 we receive an EXEC event instead of the expected SIGTRAP.
1968 If inferior gets a signal, we may decide to start it up again
1969 instead of returning. That is why there is a loop in this function.
1970 When this function actually returns it means the inferior
1971 should be left stopped and GDB should read more commands. */
1974 wait_for_inferior (int treat_exec_as_sigtrap
)
1976 struct cleanup
*old_cleanups
;
1977 struct execution_control_state ecss
;
1978 struct execution_control_state
*ecs
;
1982 (gdb_stdlog
, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
1983 treat_exec_as_sigtrap
);
1986 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
1989 memset (ecs
, 0, sizeof (*ecs
));
1991 overlay_cache_invalid
= 1;
1993 /* We'll update this if & when we switch to a new thread. */
1994 previous_inferior_ptid
= inferior_ptid
;
1996 /* We have to invalidate the registers BEFORE calling target_wait
1997 because they can be loaded from the target while in target_wait.
1998 This makes remote debugging a bit more efficient for those
1999 targets that provide critical registers as part of their normal
2000 status mechanism. */
2002 registers_changed ();
2006 struct cleanup
*old_chain
;
2008 if (deprecated_target_wait_hook
)
2009 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2011 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2014 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2016 if (treat_exec_as_sigtrap
&& ecs
->ws
.kind
== TARGET_WAITKIND_EXECD
)
2018 xfree (ecs
->ws
.value
.execd_pathname
);
2019 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2020 ecs
->ws
.value
.sig
= TARGET_SIGNAL_TRAP
;
2023 /* If an error happens while handling the event, propagate GDB's
2024 knowledge of the executing state to the frontend/user running
2026 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2028 /* Now figure out what to do with the result of the result. */
2029 handle_inferior_event (ecs
);
2031 /* No error, don't finish the state yet. */
2032 discard_cleanups (old_chain
);
2034 if (!ecs
->wait_some_more
)
2038 do_cleanups (old_cleanups
);
2041 /* Asynchronous version of wait_for_inferior. It is called by the
2042 event loop whenever a change of state is detected on the file
2043 descriptor corresponding to the target. It can be called more than
2044 once to complete a single execution command. In such cases we need
2045 to keep the state in a global variable ECSS. If it is the last time
2046 that this function is called for a single execution command, then
2047 report to the user that the inferior has stopped, and do the
2048 necessary cleanups. */
2051 fetch_inferior_event (void *client_data
)
2053 struct execution_control_state ecss
;
2054 struct execution_control_state
*ecs
= &ecss
;
2055 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2056 struct cleanup
*ts_old_chain
;
2057 int was_sync
= sync_execution
;
2059 memset (ecs
, 0, sizeof (*ecs
));
2061 overlay_cache_invalid
= 1;
2063 /* We can only rely on wait_for_more being correct before handling
2064 the event in all-stop, but previous_inferior_ptid isn't used in
2066 if (!ecs
->wait_some_more
)
2067 /* We'll update this if & when we switch to a new thread. */
2068 previous_inferior_ptid
= inferior_ptid
;
2071 /* In non-stop mode, the user/frontend should not notice a thread
2072 switch due to internal events. Make sure we reverse to the
2073 user selected thread and frame after handling the event and
2074 running any breakpoint commands. */
2075 make_cleanup_restore_current_thread ();
2077 /* We have to invalidate the registers BEFORE calling target_wait
2078 because they can be loaded from the target while in target_wait.
2079 This makes remote debugging a bit more efficient for those
2080 targets that provide critical registers as part of their normal
2081 status mechanism. */
2083 registers_changed ();
2085 if (deprecated_target_wait_hook
)
2087 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2089 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2092 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2095 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
2096 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2097 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2098 /* In non-stop mode, each thread is handled individually. Switch
2099 early, so the global state is set correctly for this
2101 context_switch (ecs
->ptid
);
2103 /* If an error happens while handling the event, propagate GDB's
2104 knowledge of the executing state to the frontend/user running
2107 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2109 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2111 /* Now figure out what to do with the result of the result. */
2112 handle_inferior_event (ecs
);
2114 if (!ecs
->wait_some_more
)
2116 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2118 delete_step_thread_step_resume_breakpoint ();
2120 /* We may not find an inferior if this was a process exit. */
2121 if (inf
== NULL
|| inf
->stop_soon
== NO_STOP_QUIETLY
)
2124 if (target_has_execution
2125 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2126 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2127 && ecs
->event_thread
->step_multi
2128 && ecs
->event_thread
->stop_step
)
2129 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2131 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2134 /* No error, don't finish the thread states yet. */
2135 discard_cleanups (ts_old_chain
);
2137 /* Revert thread and frame. */
2138 do_cleanups (old_chain
);
2140 /* If the inferior was in sync execution mode, and now isn't,
2141 restore the prompt. */
2142 if (was_sync
&& !sync_execution
)
2143 display_gdb_prompt (0);
2146 /* Record the frame and location we're currently stepping through. */
2148 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2150 struct thread_info
*tp
= inferior_thread ();
2152 tp
->step_frame_id
= get_frame_id (frame
);
2153 tp
->step_stack_frame_id
= get_stack_frame_id (frame
);
2155 tp
->current_symtab
= sal
.symtab
;
2156 tp
->current_line
= sal
.line
;
2159 /* Prepare an execution control state for looping through a
2160 wait_for_inferior-type loop. */
2163 init_execution_control_state (struct execution_control_state
*ecs
)
2165 ecs
->random_signal
= 0;
2168 /* Clear context switchable stepping state. */
2171 init_thread_stepping_state (struct thread_info
*tss
)
2173 tss
->stepping_over_breakpoint
= 0;
2174 tss
->step_after_step_resume_breakpoint
= 0;
2175 tss
->stepping_through_solib_after_catch
= 0;
2176 tss
->stepping_through_solib_catchpoints
= NULL
;
2179 /* Return the cached copy of the last pid/waitstatus returned by
2180 target_wait()/deprecated_target_wait_hook(). The data is actually
2181 cached by handle_inferior_event(), which gets called immediately
2182 after target_wait()/deprecated_target_wait_hook(). */
2185 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2187 *ptidp
= target_last_wait_ptid
;
2188 *status
= target_last_waitstatus
;
2192 nullify_last_target_wait_ptid (void)
2194 target_last_wait_ptid
= minus_one_ptid
;
2197 /* Switch thread contexts. */
2200 context_switch (ptid_t ptid
)
2204 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2205 target_pid_to_str (inferior_ptid
));
2206 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2207 target_pid_to_str (ptid
));
2210 switch_to_thread (ptid
);
2214 adjust_pc_after_break (struct execution_control_state
*ecs
)
2216 struct regcache
*regcache
;
2217 struct gdbarch
*gdbarch
;
2218 CORE_ADDR breakpoint_pc
;
2220 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2221 we aren't, just return.
2223 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2224 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2225 implemented by software breakpoints should be handled through the normal
2228 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2229 different signals (SIGILL or SIGEMT for instance), but it is less
2230 clear where the PC is pointing afterwards. It may not match
2231 gdbarch_decr_pc_after_break. I don't know any specific target that
2232 generates these signals at breakpoints (the code has been in GDB since at
2233 least 1992) so I can not guess how to handle them here.
2235 In earlier versions of GDB, a target with
2236 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2237 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2238 target with both of these set in GDB history, and it seems unlikely to be
2239 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2241 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2244 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
2247 /* In reverse execution, when a breakpoint is hit, the instruction
2248 under it has already been de-executed. The reported PC always
2249 points at the breakpoint address, so adjusting it further would
2250 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2253 B1 0x08000000 : INSN1
2254 B2 0x08000001 : INSN2
2256 PC -> 0x08000003 : INSN4
2258 Say you're stopped at 0x08000003 as above. Reverse continuing
2259 from that point should hit B2 as below. Reading the PC when the
2260 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2261 been de-executed already.
2263 B1 0x08000000 : INSN1
2264 B2 PC -> 0x08000001 : INSN2
2268 We can't apply the same logic as for forward execution, because
2269 we would wrongly adjust the PC to 0x08000000, since there's a
2270 breakpoint at PC - 1. We'd then report a hit on B1, although
2271 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2273 if (execution_direction
== EXEC_REVERSE
)
2276 /* If this target does not decrement the PC after breakpoints, then
2277 we have nothing to do. */
2278 regcache
= get_thread_regcache (ecs
->ptid
);
2279 gdbarch
= get_regcache_arch (regcache
);
2280 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
2283 /* Find the location where (if we've hit a breakpoint) the
2284 breakpoint would be. */
2285 breakpoint_pc
= regcache_read_pc (regcache
)
2286 - gdbarch_decr_pc_after_break (gdbarch
);
2288 /* Check whether there actually is a software breakpoint inserted at
2291 If in non-stop mode, a race condition is possible where we've
2292 removed a breakpoint, but stop events for that breakpoint were
2293 already queued and arrive later. To suppress those spurious
2294 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
2295 and retire them after a number of stop events are reported. */
2296 if (software_breakpoint_inserted_here_p (breakpoint_pc
)
2297 || (non_stop
&& moribund_breakpoint_here_p (breakpoint_pc
)))
2299 struct cleanup
*old_cleanups
= NULL
;
2301 old_cleanups
= record_gdb_operation_disable_set ();
2303 /* When using hardware single-step, a SIGTRAP is reported for both
2304 a completed single-step and a software breakpoint. Need to
2305 differentiate between the two, as the latter needs adjusting
2306 but the former does not.
2308 The SIGTRAP can be due to a completed hardware single-step only if
2309 - we didn't insert software single-step breakpoints
2310 - the thread to be examined is still the current thread
2311 - this thread is currently being stepped
2313 If any of these events did not occur, we must have stopped due
2314 to hitting a software breakpoint, and have to back up to the
2317 As a special case, we could have hardware single-stepped a
2318 software breakpoint. In this case (prev_pc == breakpoint_pc),
2319 we also need to back up to the breakpoint address. */
2321 if (singlestep_breakpoints_inserted_p
2322 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
2323 || !currently_stepping (ecs
->event_thread
)
2324 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
2325 regcache_write_pc (regcache
, breakpoint_pc
);
2328 do_cleanups (old_cleanups
);
2333 init_infwait_state (void)
2335 waiton_ptid
= pid_to_ptid (-1);
2336 infwait_state
= infwait_normal_state
;
2340 error_is_running (void)
2343 Cannot execute this command while the selected thread is running."));
2347 ensure_not_running (void)
2349 if (is_running (inferior_ptid
))
2350 error_is_running ();
2354 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
2356 for (frame
= get_prev_frame (frame
);
2358 frame
= get_prev_frame (frame
))
2360 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
2362 if (get_frame_type (frame
) != INLINE_FRAME
)
2369 /* Given an execution control state that has been freshly filled in
2370 by an event from the inferior, figure out what it means and take
2371 appropriate action. */
2374 handle_inferior_event (struct execution_control_state
*ecs
)
2376 struct frame_info
*frame
;
2377 struct gdbarch
*gdbarch
;
2378 int sw_single_step_trap_p
= 0;
2379 int stopped_by_watchpoint
;
2380 int stepped_after_stopped_by_watchpoint
= 0;
2381 struct symtab_and_line stop_pc_sal
;
2382 enum stop_kind stop_soon
;
2384 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2385 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2386 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
2388 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2390 stop_soon
= inf
->stop_soon
;
2393 stop_soon
= NO_STOP_QUIETLY
;
2395 /* Cache the last pid/waitstatus. */
2396 target_last_wait_ptid
= ecs
->ptid
;
2397 target_last_waitstatus
= ecs
->ws
;
2399 /* Always clear state belonging to the previous time we stopped. */
2400 stop_stack_dummy
= 0;
2402 /* If it's a new process, add it to the thread database */
2404 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
2405 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
2406 && !in_thread_list (ecs
->ptid
));
2408 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2409 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
2410 add_thread (ecs
->ptid
);
2412 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
2414 /* Dependent on valid ECS->EVENT_THREAD. */
2415 adjust_pc_after_break (ecs
);
2417 /* Dependent on the current PC value modified by adjust_pc_after_break. */
2418 reinit_frame_cache ();
2420 if (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
2422 breakpoint_retire_moribund ();
2424 /* Mark the non-executing threads accordingly. In all-stop, all
2425 threads of all processes are stopped when we get any event
2426 reported. In non-stop mode, only the event thread stops. If
2427 we're handling a process exit in non-stop mode, there's
2428 nothing to do, as threads of the dead process are gone, and
2429 threads of any other process were left running. */
2431 set_executing (minus_one_ptid
, 0);
2432 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2433 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
2434 set_executing (inferior_ptid
, 0);
2437 switch (infwait_state
)
2439 case infwait_thread_hop_state
:
2441 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
2442 /* Cancel the waiton_ptid. */
2443 waiton_ptid
= pid_to_ptid (-1);
2446 case infwait_normal_state
:
2448 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
2451 case infwait_step_watch_state
:
2453 fprintf_unfiltered (gdb_stdlog
,
2454 "infrun: infwait_step_watch_state\n");
2456 stepped_after_stopped_by_watchpoint
= 1;
2459 case infwait_nonstep_watch_state
:
2461 fprintf_unfiltered (gdb_stdlog
,
2462 "infrun: infwait_nonstep_watch_state\n");
2463 insert_breakpoints ();
2465 /* FIXME-maybe: is this cleaner than setting a flag? Does it
2466 handle things like signals arriving and other things happening
2467 in combination correctly? */
2468 stepped_after_stopped_by_watchpoint
= 1;
2472 internal_error (__FILE__
, __LINE__
, _("bad switch"));
2474 infwait_state
= infwait_normal_state
;
2476 switch (ecs
->ws
.kind
)
2478 case TARGET_WAITKIND_LOADED
:
2480 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
2481 /* Ignore gracefully during startup of the inferior, as it might
2482 be the shell which has just loaded some objects, otherwise
2483 add the symbols for the newly loaded objects. Also ignore at
2484 the beginning of an attach or remote session; we will query
2485 the full list of libraries once the connection is
2487 if (stop_soon
== NO_STOP_QUIETLY
)
2489 /* Check for any newly added shared libraries if we're
2490 supposed to be adding them automatically. Switch
2491 terminal for any messages produced by
2492 breakpoint_re_set. */
2493 target_terminal_ours_for_output ();
2494 /* NOTE: cagney/2003-11-25: Make certain that the target
2495 stack's section table is kept up-to-date. Architectures,
2496 (e.g., PPC64), use the section table to perform
2497 operations such as address => section name and hence
2498 require the table to contain all sections (including
2499 those found in shared libraries). */
2501 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2503 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2505 target_terminal_inferior ();
2507 /* If requested, stop when the dynamic linker notifies
2508 gdb of events. This allows the user to get control
2509 and place breakpoints in initializer routines for
2510 dynamically loaded objects (among other things). */
2511 if (stop_on_solib_events
)
2513 stop_stepping (ecs
);
2517 /* NOTE drow/2007-05-11: This might be a good place to check
2518 for "catch load". */
2521 /* If we are skipping through a shell, or through shared library
2522 loading that we aren't interested in, resume the program. If
2523 we're running the program normally, also resume. But stop if
2524 we're attaching or setting up a remote connection. */
2525 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
2527 /* Loading of shared libraries might have changed breakpoint
2528 addresses. Make sure new breakpoints are inserted. */
2529 if (stop_soon
== NO_STOP_QUIETLY
2530 && !breakpoints_always_inserted_mode ())
2531 insert_breakpoints ();
2532 resume (0, TARGET_SIGNAL_0
);
2533 prepare_to_wait (ecs
);
2539 case TARGET_WAITKIND_SPURIOUS
:
2541 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
2542 resume (0, TARGET_SIGNAL_0
);
2543 prepare_to_wait (ecs
);
2546 case TARGET_WAITKIND_EXITED
:
2548 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
2549 inferior_ptid
= ecs
->ptid
;
2550 target_terminal_ours (); /* Must do this before mourn anyway */
2551 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
2553 /* Record the exit code in the convenience variable $_exitcode, so
2554 that the user can inspect this again later. */
2555 set_internalvar_integer (lookup_internalvar ("_exitcode"),
2556 (LONGEST
) ecs
->ws
.value
.integer
);
2557 gdb_flush (gdb_stdout
);
2558 target_mourn_inferior ();
2559 singlestep_breakpoints_inserted_p
= 0;
2560 stop_print_frame
= 0;
2561 stop_stepping (ecs
);
2564 case TARGET_WAITKIND_SIGNALLED
:
2566 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2567 inferior_ptid
= ecs
->ptid
;
2568 stop_print_frame
= 0;
2569 target_terminal_ours (); /* Must do this before mourn anyway */
2571 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2572 reach here unless the inferior is dead. However, for years
2573 target_kill() was called here, which hints that fatal signals aren't
2574 really fatal on some systems. If that's true, then some changes
2576 target_mourn_inferior ();
2578 print_stop_reason (SIGNAL_EXITED
, ecs
->ws
.value
.sig
);
2579 singlestep_breakpoints_inserted_p
= 0;
2580 stop_stepping (ecs
);
2583 /* The following are the only cases in which we keep going;
2584 the above cases end in a continue or goto. */
2585 case TARGET_WAITKIND_FORKED
:
2586 case TARGET_WAITKIND_VFORKED
:
2588 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2590 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2592 context_switch (ecs
->ptid
);
2593 reinit_frame_cache ();
2596 /* Immediately detach breakpoints from the child before there's
2597 any chance of letting the user delete breakpoints from the
2598 breakpoint lists. If we don't do this early, it's easy to
2599 leave left over traps in the child, vis: "break foo; catch
2600 fork; c; <fork>; del; c; <child calls foo>". We only follow
2601 the fork on the last `continue', and by that time the
2602 breakpoint at "foo" is long gone from the breakpoint table.
2603 If we vforked, then we don't need to unpatch here, since both
2604 parent and child are sharing the same memory pages; we'll
2605 need to unpatch at follow/detach time instead to be certain
2606 that new breakpoints added between catchpoint hit time and
2607 vfork follow are detached. */
2608 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
2610 int child_pid
= ptid_get_pid (ecs
->ws
.value
.related_pid
);
2612 /* This won't actually modify the breakpoint list, but will
2613 physically remove the breakpoints from the child. */
2614 detach_breakpoints (child_pid
);
2617 /* In case the event is caught by a catchpoint, remember that
2618 the event is to be followed at the next resume of the thread,
2619 and not immediately. */
2620 ecs
->event_thread
->pending_follow
= ecs
->ws
;
2622 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2624 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2626 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2628 /* If no catchpoint triggered for this, then keep going. */
2629 if (ecs
->random_signal
)
2633 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2635 should_resume
= follow_fork ();
2637 ecs
->event_thread
= inferior_thread ();
2638 ecs
->ptid
= inferior_ptid
;
2643 stop_stepping (ecs
);
2646 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2647 goto process_event_stop_test
;
2649 case TARGET_WAITKIND_EXECD
:
2651 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
2653 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2655 context_switch (ecs
->ptid
);
2656 reinit_frame_cache ();
2659 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2661 /* This causes the eventpoints and symbol table to be reset.
2662 Must do this now, before trying to determine whether to
2664 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
2666 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2667 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2669 /* Note that this may be referenced from inside
2670 bpstat_stop_status above, through inferior_has_execd. */
2671 xfree (ecs
->ws
.value
.execd_pathname
);
2672 ecs
->ws
.value
.execd_pathname
= NULL
;
2674 /* If no catchpoint triggered for this, then keep going. */
2675 if (ecs
->random_signal
)
2677 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2681 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2682 goto process_event_stop_test
;
2684 /* Be careful not to try to gather much state about a thread
2685 that's in a syscall. It's frequently a losing proposition. */
2686 case TARGET_WAITKIND_SYSCALL_ENTRY
:
2688 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2689 resume (0, TARGET_SIGNAL_0
);
2690 prepare_to_wait (ecs
);
2693 /* Before examining the threads further, step this thread to
2694 get it entirely out of the syscall. (We get notice of the
2695 event when the thread is just on the verge of exiting a
2696 syscall. Stepping one instruction seems to get it back
2698 case TARGET_WAITKIND_SYSCALL_RETURN
:
2700 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2701 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
);
2702 prepare_to_wait (ecs
);
2705 case TARGET_WAITKIND_STOPPED
:
2707 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
2708 ecs
->event_thread
->stop_signal
= ecs
->ws
.value
.sig
;
2711 case TARGET_WAITKIND_NO_HISTORY
:
2712 /* Reverse execution: target ran out of history info. */
2713 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2714 print_stop_reason (NO_HISTORY
, 0);
2715 stop_stepping (ecs
);
2718 /* We had an event in the inferior, but we are not interested
2719 in handling it at this level. The lower layers have already
2720 done what needs to be done, if anything.
2722 One of the possible circumstances for this is when the
2723 inferior produces output for the console. The inferior has
2724 not stopped, and we are ignoring the event. Another possible
2725 circumstance is any event which the lower level knows will be
2726 reported multiple times without an intervening resume. */
2727 case TARGET_WAITKIND_IGNORE
:
2729 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2730 prepare_to_wait (ecs
);
2734 if (ecs
->new_thread_event
)
2737 /* Non-stop assumes that the target handles adding new threads
2738 to the thread list. */
2739 internal_error (__FILE__
, __LINE__
, "\
2740 targets should add new threads to the thread list themselves in non-stop mode.");
2742 /* We may want to consider not doing a resume here in order to
2743 give the user a chance to play with the new thread. It might
2744 be good to make that a user-settable option. */
2746 /* At this point, all threads are stopped (happens automatically
2747 in either the OS or the native code). Therefore we need to
2748 continue all threads in order to make progress. */
2750 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2751 context_switch (ecs
->ptid
);
2752 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
2753 prepare_to_wait (ecs
);
2757 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
2759 /* Do we need to clean up the state of a thread that has
2760 completed a displaced single-step? (Doing so usually affects
2761 the PC, so do it here, before we set stop_pc.) */
2762 displaced_step_fixup (ecs
->ptid
, ecs
->event_thread
->stop_signal
);
2764 /* If we either finished a single-step or hit a breakpoint, but
2765 the user wanted this thread to be stopped, pretend we got a
2766 SIG0 (generic unsignaled stop). */
2768 if (ecs
->event_thread
->stop_requested
2769 && ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2770 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2773 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2777 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = 0x%s\n",
2778 paddr_nz (stop_pc
));
2779 if (target_stopped_by_watchpoint ())
2782 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
2784 if (target_stopped_data_address (¤t_target
, &addr
))
2785 fprintf_unfiltered (gdb_stdlog
,
2786 "infrun: stopped data address = 0x%s\n",
2789 fprintf_unfiltered (gdb_stdlog
,
2790 "infrun: (no data address available)\n");
2794 if (stepping_past_singlestep_breakpoint
)
2796 gdb_assert (singlestep_breakpoints_inserted_p
);
2797 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
2798 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
2800 stepping_past_singlestep_breakpoint
= 0;
2802 /* We've either finished single-stepping past the single-step
2803 breakpoint, or stopped for some other reason. It would be nice if
2804 we could tell, but we can't reliably. */
2805 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2808 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
2809 /* Pull the single step breakpoints out of the target. */
2810 remove_single_step_breakpoints ();
2811 singlestep_breakpoints_inserted_p
= 0;
2813 ecs
->random_signal
= 0;
2815 context_switch (saved_singlestep_ptid
);
2816 if (deprecated_context_hook
)
2817 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2819 resume (1, TARGET_SIGNAL_0
);
2820 prepare_to_wait (ecs
);
2825 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
2827 /* In non-stop mode, there's never a deferred_step_ptid set. */
2828 gdb_assert (!non_stop
);
2830 /* If we stopped for some other reason than single-stepping, ignore
2831 the fact that we were supposed to switch back. */
2832 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2835 fprintf_unfiltered (gdb_stdlog
,
2836 "infrun: handling deferred step\n");
2838 /* Pull the single step breakpoints out of the target. */
2839 if (singlestep_breakpoints_inserted_p
)
2841 remove_single_step_breakpoints ();
2842 singlestep_breakpoints_inserted_p
= 0;
2845 /* Note: We do not call context_switch at this point, as the
2846 context is already set up for stepping the original thread. */
2847 switch_to_thread (deferred_step_ptid
);
2848 deferred_step_ptid
= null_ptid
;
2849 /* Suppress spurious "Switching to ..." message. */
2850 previous_inferior_ptid
= inferior_ptid
;
2852 resume (1, TARGET_SIGNAL_0
);
2853 prepare_to_wait (ecs
);
2857 deferred_step_ptid
= null_ptid
;
2860 /* See if a thread hit a thread-specific breakpoint that was meant for
2861 another thread. If so, then step that thread past the breakpoint,
2864 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2866 int thread_hop_needed
= 0;
2868 /* Check if a regular breakpoint has been hit before checking
2869 for a potential single step breakpoint. Otherwise, GDB will
2870 not see this breakpoint hit when stepping onto breakpoints. */
2871 if (regular_breakpoint_inserted_here_p (stop_pc
))
2873 ecs
->random_signal
= 0;
2874 if (!breakpoint_thread_match (stop_pc
, ecs
->ptid
))
2875 thread_hop_needed
= 1;
2877 else if (singlestep_breakpoints_inserted_p
)
2879 /* We have not context switched yet, so this should be true
2880 no matter which thread hit the singlestep breakpoint. */
2881 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
2883 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
2885 target_pid_to_str (ecs
->ptid
));
2887 ecs
->random_signal
= 0;
2888 /* The call to in_thread_list is necessary because PTIDs sometimes
2889 change when we go from single-threaded to multi-threaded. If
2890 the singlestep_ptid is still in the list, assume that it is
2891 really different from ecs->ptid. */
2892 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
2893 && in_thread_list (singlestep_ptid
))
2895 /* If the PC of the thread we were trying to single-step
2896 has changed, discard this event (which we were going
2897 to ignore anyway), and pretend we saw that thread
2898 trap. This prevents us continuously moving the
2899 single-step breakpoint forward, one instruction at a
2900 time. If the PC has changed, then the thread we were
2901 trying to single-step has trapped or been signalled,
2902 but the event has not been reported to GDB yet.
2904 There might be some cases where this loses signal
2905 information, if a signal has arrived at exactly the
2906 same time that the PC changed, but this is the best
2907 we can do with the information available. Perhaps we
2908 should arrange to report all events for all threads
2909 when they stop, or to re-poll the remote looking for
2910 this particular thread (i.e. temporarily enable
2913 CORE_ADDR new_singlestep_pc
2914 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
2916 if (new_singlestep_pc
!= singlestep_pc
)
2918 enum target_signal stop_signal
;
2921 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
2922 " but expected thread advanced also\n");
2924 /* The current context still belongs to
2925 singlestep_ptid. Don't swap here, since that's
2926 the context we want to use. Just fudge our
2927 state and continue. */
2928 stop_signal
= ecs
->event_thread
->stop_signal
;
2929 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2930 ecs
->ptid
= singlestep_ptid
;
2931 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
2932 ecs
->event_thread
->stop_signal
= stop_signal
;
2933 stop_pc
= new_singlestep_pc
;
2938 fprintf_unfiltered (gdb_stdlog
,
2939 "infrun: unexpected thread\n");
2941 thread_hop_needed
= 1;
2942 stepping_past_singlestep_breakpoint
= 1;
2943 saved_singlestep_ptid
= singlestep_ptid
;
2948 if (thread_hop_needed
)
2950 struct regcache
*thread_regcache
;
2951 int remove_status
= 0;
2954 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
2956 /* Switch context before touching inferior memory, the
2957 previous thread may have exited. */
2958 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
2959 context_switch (ecs
->ptid
);
2961 /* Saw a breakpoint, but it was hit by the wrong thread.
2964 if (singlestep_breakpoints_inserted_p
)
2966 /* Pull the single step breakpoints out of the target. */
2967 remove_single_step_breakpoints ();
2968 singlestep_breakpoints_inserted_p
= 0;
2971 /* If the arch can displace step, don't remove the
2973 thread_regcache
= get_thread_regcache (ecs
->ptid
);
2974 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
2975 remove_status
= remove_breakpoints ();
2977 /* Did we fail to remove breakpoints? If so, try
2978 to set the PC past the bp. (There's at least
2979 one situation in which we can fail to remove
2980 the bp's: On HP-UX's that use ttrace, we can't
2981 change the address space of a vforking child
2982 process until the child exits (well, okay, not
2983 then either :-) or execs. */
2984 if (remove_status
!= 0)
2985 error (_("Cannot step over breakpoint hit in wrong thread"));
2990 /* Only need to require the next event from this
2991 thread in all-stop mode. */
2992 waiton_ptid
= ecs
->ptid
;
2993 infwait_state
= infwait_thread_hop_state
;
2996 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2998 registers_changed ();
3002 else if (singlestep_breakpoints_inserted_p
)
3004 sw_single_step_trap_p
= 1;
3005 ecs
->random_signal
= 0;
3009 ecs
->random_signal
= 1;
3011 /* See if something interesting happened to the non-current thread. If
3012 so, then switch to that thread. */
3013 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3016 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3018 context_switch (ecs
->ptid
);
3020 if (deprecated_context_hook
)
3021 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3024 /* At this point, get hold of the now-current thread's frame. */
3025 frame
= get_current_frame ();
3026 gdbarch
= get_frame_arch (frame
);
3028 if (singlestep_breakpoints_inserted_p
)
3030 /* Pull the single step breakpoints out of the target. */
3031 remove_single_step_breakpoints ();
3032 singlestep_breakpoints_inserted_p
= 0;
3035 if (stepped_after_stopped_by_watchpoint
)
3036 stopped_by_watchpoint
= 0;
3038 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
3040 /* If necessary, step over this watchpoint. We'll be back to display
3042 if (stopped_by_watchpoint
3043 && (target_have_steppable_watchpoint
3044 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
3046 /* At this point, we are stopped at an instruction which has
3047 attempted to write to a piece of memory under control of
3048 a watchpoint. The instruction hasn't actually executed
3049 yet. If we were to evaluate the watchpoint expression
3050 now, we would get the old value, and therefore no change
3051 would seem to have occurred.
3053 In order to make watchpoints work `right', we really need
3054 to complete the memory write, and then evaluate the
3055 watchpoint expression. We do this by single-stepping the
3058 It may not be necessary to disable the watchpoint to stop over
3059 it. For example, the PA can (with some kernel cooperation)
3060 single step over a watchpoint without disabling the watchpoint.
3062 It is far more common to need to disable a watchpoint to step
3063 the inferior over it. If we have non-steppable watchpoints,
3064 we must disable the current watchpoint; it's simplest to
3065 disable all watchpoints and breakpoints. */
3068 if (!target_have_steppable_watchpoint
)
3069 remove_breakpoints ();
3071 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
3072 target_resume (ecs
->ptid
, hw_step
, TARGET_SIGNAL_0
);
3073 registers_changed ();
3074 waiton_ptid
= ecs
->ptid
;
3075 if (target_have_steppable_watchpoint
)
3076 infwait_state
= infwait_step_watch_state
;
3078 infwait_state
= infwait_nonstep_watch_state
;
3079 prepare_to_wait (ecs
);
3083 ecs
->stop_func_start
= 0;
3084 ecs
->stop_func_end
= 0;
3085 ecs
->stop_func_name
= 0;
3086 /* Don't care about return value; stop_func_start and stop_func_name
3087 will both be 0 if it doesn't work. */
3088 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3089 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3090 ecs
->stop_func_start
3091 += gdbarch_deprecated_function_start_offset (gdbarch
);
3092 ecs
->event_thread
->stepping_over_breakpoint
= 0;
3093 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
3094 ecs
->event_thread
->stop_step
= 0;
3095 stop_print_frame
= 1;
3096 ecs
->random_signal
= 0;
3097 stopped_by_random_signal
= 0;
3099 /* Hide inlined functions starting here, unless we just performed stepi or
3100 nexti. After stepi and nexti, always show the innermost frame (not any
3101 inline function call sites). */
3102 if (ecs
->event_thread
->step_range_end
!= 1)
3103 skip_inline_frames (ecs
->ptid
);
3105 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3106 && ecs
->event_thread
->trap_expected
3107 && gdbarch_single_step_through_delay_p (gdbarch
)
3108 && currently_stepping (ecs
->event_thread
))
3110 /* We're trying to step off a breakpoint. Turns out that we're
3111 also on an instruction that needs to be stepped multiple
3112 times before it's been fully executing. E.g., architectures
3113 with a delay slot. It needs to be stepped twice, once for
3114 the instruction and once for the delay slot. */
3115 int step_through_delay
3116 = gdbarch_single_step_through_delay (gdbarch
, frame
);
3117 if (debug_infrun
&& step_through_delay
)
3118 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
3119 if (ecs
->event_thread
->step_range_end
== 0 && step_through_delay
)
3121 /* The user issued a continue when stopped at a breakpoint.
3122 Set up for another trap and get out of here. */
3123 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3127 else if (step_through_delay
)
3129 /* The user issued a step when stopped at a breakpoint.
3130 Maybe we should stop, maybe we should not - the delay
3131 slot *might* correspond to a line of source. In any
3132 case, don't decide that here, just set
3133 ecs->stepping_over_breakpoint, making sure we
3134 single-step again before breakpoints are re-inserted. */
3135 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3139 /* Look at the cause of the stop, and decide what to do.
3140 The alternatives are:
3141 1) stop_stepping and return; to really stop and return to the debugger,
3142 2) keep_going and return to start up again
3143 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
3144 3) set ecs->random_signal to 1, and the decision between 1 and 2
3145 will be made according to the signal handling tables. */
3147 /* First, distinguish signals caused by the debugger from signals
3148 that have to do with the program's own actions. Note that
3149 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3150 on the operating system version. Here we detect when a SIGILL or
3151 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3152 something similar for SIGSEGV, since a SIGSEGV will be generated
3153 when we're trying to execute a breakpoint instruction on a
3154 non-executable stack. This happens for call dummy breakpoints
3155 for architectures like SPARC that place call dummies on the
3158 If we're doing a displaced step past a breakpoint, then the
3159 breakpoint is always inserted at the original instruction;
3160 non-standard signals can't be explained by the breakpoint. */
3161 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3162 || (! ecs
->event_thread
->trap_expected
3163 && breakpoint_inserted_here_p (stop_pc
)
3164 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_ILL
3165 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_SEGV
3166 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_EMT
))
3167 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3168 || stop_soon
== STOP_QUIETLY_REMOTE
)
3170 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
3173 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
3174 stop_print_frame
= 0;
3175 stop_stepping (ecs
);
3179 /* This is originated from start_remote(), start_inferior() and
3180 shared libraries hook functions. */
3181 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
3184 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3185 stop_stepping (ecs
);
3189 /* This originates from attach_command(). We need to overwrite
3190 the stop_signal here, because some kernels don't ignore a
3191 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
3192 See more comments in inferior.h. On the other hand, if we
3193 get a non-SIGSTOP, report it to the user - assume the backend
3194 will handle the SIGSTOP if it should show up later.
3196 Also consider that the attach is complete when we see a
3197 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
3198 target extended-remote report it instead of a SIGSTOP
3199 (e.g. gdbserver). We already rely on SIGTRAP being our
3200 signal, so this is no exception.
3202 Also consider that the attach is complete when we see a
3203 TARGET_SIGNAL_0. In non-stop mode, GDB will explicitly tell
3204 the target to stop all threads of the inferior, in case the
3205 low level attach operation doesn't stop them implicitly. If
3206 they weren't stopped implicitly, then the stub will report a
3207 TARGET_SIGNAL_0, meaning: stopped for no particular reason
3208 other than GDB's request. */
3209 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3210 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_STOP
3211 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3212 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_0
))
3214 stop_stepping (ecs
);
3215 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3219 /* See if there is a breakpoint at the current PC. */
3220 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
3222 /* Following in case break condition called a
3224 stop_print_frame
= 1;
3226 /* NOTE: cagney/2003-03-29: These two checks for a random signal
3227 at one stage in the past included checks for an inferior
3228 function call's call dummy's return breakpoint. The original
3229 comment, that went with the test, read:
3231 ``End of a stack dummy. Some systems (e.g. Sony news) give
3232 another signal besides SIGTRAP, so check here as well as
3235 If someone ever tries to get call dummys on a
3236 non-executable stack to work (where the target would stop
3237 with something like a SIGSEGV), then those tests might need
3238 to be re-instated. Given, however, that the tests were only
3239 enabled when momentary breakpoints were not being used, I
3240 suspect that it won't be the case.
3242 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
3243 be necessary for call dummies on a non-executable stack on
3246 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
3248 = !(bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
)
3249 || ecs
->event_thread
->trap_expected
3250 || (ecs
->event_thread
->step_range_end
3251 && ecs
->event_thread
->step_resume_breakpoint
== NULL
));
3254 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
3255 if (!ecs
->random_signal
)
3256 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
3260 /* When we reach this point, we've pretty much decided
3261 that the reason for stopping must've been a random
3262 (unexpected) signal. */
3265 ecs
->random_signal
= 1;
3267 process_event_stop_test
:
3269 /* Re-fetch current thread's frame in case we did a
3270 "goto process_event_stop_test" above. */
3271 frame
= get_current_frame ();
3272 gdbarch
= get_frame_arch (frame
);
3274 /* For the program's own signals, act according to
3275 the signal handling tables. */
3277 if (ecs
->random_signal
)
3279 /* Signal not for debugging purposes. */
3283 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
3284 ecs
->event_thread
->stop_signal
);
3286 stopped_by_random_signal
= 1;
3288 if (signal_print
[ecs
->event_thread
->stop_signal
])
3291 target_terminal_ours_for_output ();
3292 print_stop_reason (SIGNAL_RECEIVED
, ecs
->event_thread
->stop_signal
);
3294 /* Always stop on signals if we're either just gaining control
3295 of the program, or the user explicitly requested this thread
3296 to remain stopped. */
3297 if (stop_soon
!= NO_STOP_QUIETLY
3298 || ecs
->event_thread
->stop_requested
3299 || signal_stop_state (ecs
->event_thread
->stop_signal
))
3301 stop_stepping (ecs
);
3304 /* If not going to stop, give terminal back
3305 if we took it away. */
3307 target_terminal_inferior ();
3309 /* Clear the signal if it should not be passed. */
3310 if (signal_program
[ecs
->event_thread
->stop_signal
] == 0)
3311 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3313 if (ecs
->event_thread
->prev_pc
== stop_pc
3314 && ecs
->event_thread
->trap_expected
3315 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
3317 /* We were just starting a new sequence, attempting to
3318 single-step off of a breakpoint and expecting a SIGTRAP.
3319 Instead this signal arrives. This signal will take us out
3320 of the stepping range so GDB needs to remember to, when
3321 the signal handler returns, resume stepping off that
3323 /* To simplify things, "continue" is forced to use the same
3324 code paths as single-step - set a breakpoint at the
3325 signal return address and then, once hit, step off that
3328 fprintf_unfiltered (gdb_stdlog
,
3329 "infrun: signal arrived while stepping over "
3332 insert_step_resume_breakpoint_at_frame (frame
);
3333 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
3338 if (ecs
->event_thread
->step_range_end
!= 0
3339 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_0
3340 && (ecs
->event_thread
->step_range_start
<= stop_pc
3341 && stop_pc
< ecs
->event_thread
->step_range_end
)
3342 && frame_id_eq (get_stack_frame_id (frame
),
3343 ecs
->event_thread
->step_stack_frame_id
)
3344 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
3346 /* The inferior is about to take a signal that will take it
3347 out of the single step range. Set a breakpoint at the
3348 current PC (which is presumably where the signal handler
3349 will eventually return) and then allow the inferior to
3352 Note that this is only needed for a signal delivered
3353 while in the single-step range. Nested signals aren't a
3354 problem as they eventually all return. */
3356 fprintf_unfiltered (gdb_stdlog
,
3357 "infrun: signal may take us out of "
3358 "single-step range\n");
3360 insert_step_resume_breakpoint_at_frame (frame
);
3365 /* Note: step_resume_breakpoint may be non-NULL. This occures
3366 when either there's a nested signal, or when there's a
3367 pending signal enabled just as the signal handler returns
3368 (leaving the inferior at the step-resume-breakpoint without
3369 actually executing it). Either way continue until the
3370 breakpoint is really hit. */
3375 /* Handle cases caused by hitting a breakpoint. */
3377 CORE_ADDR jmp_buf_pc
;
3378 struct bpstat_what what
;
3380 what
= bpstat_what (ecs
->event_thread
->stop_bpstat
);
3382 if (what
.call_dummy
)
3384 stop_stack_dummy
= 1;
3387 switch (what
.main_action
)
3389 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
3390 /* If we hit the breakpoint at longjmp while stepping, we
3391 install a momentary breakpoint at the target of the
3395 fprintf_unfiltered (gdb_stdlog
,
3396 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
3398 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3400 if (!gdbarch_get_longjmp_target_p (gdbarch
)
3401 || !gdbarch_get_longjmp_target (gdbarch
, frame
, &jmp_buf_pc
))
3404 fprintf_unfiltered (gdb_stdlog
, "\
3405 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
3410 /* We're going to replace the current step-resume breakpoint
3411 with a longjmp-resume breakpoint. */
3412 delete_step_resume_breakpoint (ecs
->event_thread
);
3414 /* Insert a breakpoint at resume address. */
3415 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
3420 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
3422 fprintf_unfiltered (gdb_stdlog
,
3423 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
3425 gdb_assert (ecs
->event_thread
->step_resume_breakpoint
!= NULL
);
3426 delete_step_resume_breakpoint (ecs
->event_thread
);
3428 ecs
->event_thread
->stop_step
= 1;
3429 print_stop_reason (END_STEPPING_RANGE
, 0);
3430 stop_stepping (ecs
);
3433 case BPSTAT_WHAT_SINGLE
:
3435 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
3436 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3437 /* Still need to check other stuff, at least the case
3438 where we are stepping and step out of the right range. */
3441 case BPSTAT_WHAT_STOP_NOISY
:
3443 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
3444 stop_print_frame
= 1;
3446 /* We are about to nuke the step_resume_breakpointt via the
3447 cleanup chain, so no need to worry about it here. */
3449 stop_stepping (ecs
);
3452 case BPSTAT_WHAT_STOP_SILENT
:
3454 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
3455 stop_print_frame
= 0;
3457 /* We are about to nuke the step_resume_breakpoin via the
3458 cleanup chain, so no need to worry about it here. */
3460 stop_stepping (ecs
);
3463 case BPSTAT_WHAT_STEP_RESUME
:
3465 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
3467 delete_step_resume_breakpoint (ecs
->event_thread
);
3468 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
3470 /* Back when the step-resume breakpoint was inserted, we
3471 were trying to single-step off a breakpoint. Go back
3473 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
3474 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3478 if (stop_pc
== ecs
->stop_func_start
3479 && execution_direction
== EXEC_REVERSE
)
3481 /* We are stepping over a function call in reverse, and
3482 just hit the step-resume breakpoint at the start
3483 address of the function. Go back to single-stepping,
3484 which should take us back to the function call. */
3485 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3491 case BPSTAT_WHAT_CHECK_SHLIBS
:
3494 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
3496 /* Check for any newly added shared libraries if we're
3497 supposed to be adding them automatically. Switch
3498 terminal for any messages produced by
3499 breakpoint_re_set. */
3500 target_terminal_ours_for_output ();
3501 /* NOTE: cagney/2003-11-25: Make certain that the target
3502 stack's section table is kept up-to-date. Architectures,
3503 (e.g., PPC64), use the section table to perform
3504 operations such as address => section name and hence
3505 require the table to contain all sections (including
3506 those found in shared libraries). */
3508 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
3510 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
3512 target_terminal_inferior ();
3514 /* If requested, stop when the dynamic linker notifies
3515 gdb of events. This allows the user to get control
3516 and place breakpoints in initializer routines for
3517 dynamically loaded objects (among other things). */
3518 if (stop_on_solib_events
|| stop_stack_dummy
)
3520 stop_stepping (ecs
);
3525 /* We want to step over this breakpoint, then keep going. */
3526 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3532 case BPSTAT_WHAT_LAST
:
3533 /* Not a real code, but listed here to shut up gcc -Wall. */
3535 case BPSTAT_WHAT_KEEP_CHECKING
:
3540 /* We come here if we hit a breakpoint but should not
3541 stop for it. Possibly we also were stepping
3542 and should stop for that. So fall through and
3543 test for stepping. But, if not stepping,
3546 /* In all-stop mode, if we're currently stepping but have stopped in
3547 some other thread, we need to switch back to the stepped thread. */
3550 struct thread_info
*tp
;
3551 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
3555 /* However, if the current thread is blocked on some internal
3556 breakpoint, and we simply need to step over that breakpoint
3557 to get it going again, do that first. */
3558 if ((ecs
->event_thread
->trap_expected
3559 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
3560 || ecs
->event_thread
->stepping_over_breakpoint
)
3566 /* If the stepping thread exited, then don't try to switch
3567 back and resume it, which could fail in several different
3568 ways depending on the target. Instead, just keep going.
3570 We can find a stepping dead thread in the thread list in
3573 - The target supports thread exit events, and when the
3574 target tries to delete the thread from the thread list,
3575 inferior_ptid pointed at the exiting thread. In such
3576 case, calling delete_thread does not really remove the
3577 thread from the list; instead, the thread is left listed,
3578 with 'exited' state.
3580 - The target's debug interface does not support thread
3581 exit events, and so we have no idea whatsoever if the
3582 previously stepping thread is still alive. For that
3583 reason, we need to synchronously query the target
3585 if (is_exited (tp
->ptid
)
3586 || !target_thread_alive (tp
->ptid
))
3589 fprintf_unfiltered (gdb_stdlog
, "\
3590 infrun: not switching back to stepped thread, it has vanished\n");
3592 delete_thread (tp
->ptid
);
3597 /* Otherwise, we no longer expect a trap in the current thread.
3598 Clear the trap_expected flag before switching back -- this is
3599 what keep_going would do as well, if we called it. */
3600 ecs
->event_thread
->trap_expected
= 0;
3603 fprintf_unfiltered (gdb_stdlog
,
3604 "infrun: switching back to stepped thread\n");
3606 ecs
->event_thread
= tp
;
3607 ecs
->ptid
= tp
->ptid
;
3608 context_switch (ecs
->ptid
);
3614 /* Are we stepping to get the inferior out of the dynamic linker's
3615 hook (and possibly the dld itself) after catching a shlib
3617 if (ecs
->event_thread
->stepping_through_solib_after_catch
)
3619 #if defined(SOLIB_ADD)
3620 /* Have we reached our destination? If not, keep going. */
3621 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
3624 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
3625 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3631 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
3632 /* Else, stop and report the catchpoint(s) whose triggering
3633 caused us to begin stepping. */
3634 ecs
->event_thread
->stepping_through_solib_after_catch
= 0;
3635 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
3636 ecs
->event_thread
->stop_bpstat
3637 = bpstat_copy (ecs
->event_thread
->stepping_through_solib_catchpoints
);
3638 bpstat_clear (&ecs
->event_thread
->stepping_through_solib_catchpoints
);
3639 stop_print_frame
= 1;
3640 stop_stepping (ecs
);
3644 if (ecs
->event_thread
->step_resume_breakpoint
)
3647 fprintf_unfiltered (gdb_stdlog
,
3648 "infrun: step-resume breakpoint is inserted\n");
3650 /* Having a step-resume breakpoint overrides anything
3651 else having to do with stepping commands until
3652 that breakpoint is reached. */
3657 if (ecs
->event_thread
->step_range_end
== 0)
3660 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
3661 /* Likewise if we aren't even stepping. */
3666 /* If stepping through a line, keep going if still within it.
3668 Note that step_range_end is the address of the first instruction
3669 beyond the step range, and NOT the address of the last instruction
3672 Note also that during reverse execution, we may be stepping
3673 through a function epilogue and therefore must detect when
3674 the current-frame changes in the middle of a line. */
3676 if (stop_pc
>= ecs
->event_thread
->step_range_start
3677 && stop_pc
< ecs
->event_thread
->step_range_end
3678 && (execution_direction
!= EXEC_REVERSE
3679 || frame_id_eq (get_frame_id (frame
),
3680 ecs
->event_thread
->step_frame_id
)))
3683 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping inside range [0x%s-0x%s]\n",
3684 paddr_nz (ecs
->event_thread
->step_range_start
),
3685 paddr_nz (ecs
->event_thread
->step_range_end
));
3687 /* When stepping backward, stop at beginning of line range
3688 (unless it's the function entry point, in which case
3689 keep going back to the call point). */
3690 if (stop_pc
== ecs
->event_thread
->step_range_start
3691 && stop_pc
!= ecs
->stop_func_start
3692 && execution_direction
== EXEC_REVERSE
)
3694 ecs
->event_thread
->stop_step
= 1;
3695 print_stop_reason (END_STEPPING_RANGE
, 0);
3696 stop_stepping (ecs
);
3704 /* We stepped out of the stepping range. */
3706 /* If we are stepping at the source level and entered the runtime
3707 loader dynamic symbol resolution code...
3709 EXEC_FORWARD: we keep on single stepping until we exit the run
3710 time loader code and reach the callee's address.
3712 EXEC_REVERSE: we've already executed the callee (backward), and
3713 the runtime loader code is handled just like any other
3714 undebuggable function call. Now we need only keep stepping
3715 backward through the trampoline code, and that's handled further
3716 down, so there is nothing for us to do here. */
3718 if (execution_direction
!= EXEC_REVERSE
3719 && ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3720 && in_solib_dynsym_resolve_code (stop_pc
))
3722 CORE_ADDR pc_after_resolver
=
3723 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
3726 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
3728 if (pc_after_resolver
)
3730 /* Set up a step-resume breakpoint at the address
3731 indicated by SKIP_SOLIB_RESOLVER. */
3732 struct symtab_and_line sr_sal
;
3734 sr_sal
.pc
= pc_after_resolver
;
3736 insert_step_resume_breakpoint_at_sal (gdbarch
,
3737 sr_sal
, null_frame_id
);
3744 if (ecs
->event_thread
->step_range_end
!= 1
3745 && (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3746 || ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3747 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
3750 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
3751 /* The inferior, while doing a "step" or "next", has ended up in
3752 a signal trampoline (either by a signal being delivered or by
3753 the signal handler returning). Just single-step until the
3754 inferior leaves the trampoline (either by calling the handler
3760 /* Check for subroutine calls. The check for the current frame
3761 equalling the step ID is not necessary - the check of the
3762 previous frame's ID is sufficient - but it is a common case and
3763 cheaper than checking the previous frame's ID.
3765 NOTE: frame_id_eq will never report two invalid frame IDs as
3766 being equal, so to get into this block, both the current and
3767 previous frame must have valid frame IDs. */
3768 if (!frame_id_eq (get_stack_frame_id (frame
),
3769 ecs
->event_thread
->step_stack_frame_id
)
3770 && (frame_id_eq (frame_unwind_caller_id (frame
),
3771 ecs
->event_thread
->step_stack_frame_id
)
3772 || execution_direction
== EXEC_REVERSE
))
3774 CORE_ADDR real_stop_pc
;
3777 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
3779 if ((ecs
->event_thread
->step_over_calls
== STEP_OVER_NONE
)
3780 || ((ecs
->event_thread
->step_range_end
== 1)
3781 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
3782 ecs
->stop_func_start
)))
3784 /* I presume that step_over_calls is only 0 when we're
3785 supposed to be stepping at the assembly language level
3786 ("stepi"). Just stop. */
3787 /* Also, maybe we just did a "nexti" inside a prolog, so we
3788 thought it was a subroutine call but it was not. Stop as
3790 /* And this works the same backward as frontward. MVS */
3791 ecs
->event_thread
->stop_step
= 1;
3792 print_stop_reason (END_STEPPING_RANGE
, 0);
3793 stop_stepping (ecs
);
3797 /* Reverse stepping through solib trampolines. */
3799 if (execution_direction
== EXEC_REVERSE
3800 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
3801 || (ecs
->stop_func_start
== 0
3802 && in_solib_dynsym_resolve_code (stop_pc
))))
3804 /* Any solib trampoline code can be handled in reverse
3805 by simply continuing to single-step. We have already
3806 executed the solib function (backwards), and a few
3807 steps will take us back through the trampoline to the
3813 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3815 /* We're doing a "next".
3817 Normal (forward) execution: set a breakpoint at the
3818 callee's return address (the address at which the caller
3821 Reverse (backward) execution. set the step-resume
3822 breakpoint at the start of the function that we just
3823 stepped into (backwards), and continue to there. When we
3824 get there, we'll need to single-step back to the caller. */
3826 if (execution_direction
== EXEC_REVERSE
)
3828 struct symtab_and_line sr_sal
;
3830 /* Normal function call return (static or dynamic). */
3832 sr_sal
.pc
= ecs
->stop_func_start
;
3833 insert_step_resume_breakpoint_at_sal (gdbarch
,
3834 sr_sal
, null_frame_id
);
3837 insert_step_resume_breakpoint_at_caller (frame
);
3843 /* If we are in a function call trampoline (a stub between the
3844 calling routine and the real function), locate the real
3845 function. That's what tells us (a) whether we want to step
3846 into it at all, and (b) what prologue we want to run to the
3847 end of, if we do step into it. */
3848 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
3849 if (real_stop_pc
== 0)
3850 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
3851 if (real_stop_pc
!= 0)
3852 ecs
->stop_func_start
= real_stop_pc
;
3854 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
3856 struct symtab_and_line sr_sal
;
3858 sr_sal
.pc
= ecs
->stop_func_start
;
3860 insert_step_resume_breakpoint_at_sal (gdbarch
,
3861 sr_sal
, null_frame_id
);
3866 /* If we have line number information for the function we are
3867 thinking of stepping into, step into it.
3869 If there are several symtabs at that PC (e.g. with include
3870 files), just want to know whether *any* of them have line
3871 numbers. find_pc_line handles this. */
3873 struct symtab_and_line tmp_sal
;
3875 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3876 if (tmp_sal
.line
!= 0)
3878 if (execution_direction
== EXEC_REVERSE
)
3879 handle_step_into_function_backward (gdbarch
, ecs
);
3881 handle_step_into_function (gdbarch
, ecs
);
3886 /* If we have no line number and the step-stop-if-no-debug is
3887 set, we stop the step so that the user has a chance to switch
3888 in assembly mode. */
3889 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3890 && step_stop_if_no_debug
)
3892 ecs
->event_thread
->stop_step
= 1;
3893 print_stop_reason (END_STEPPING_RANGE
, 0);
3894 stop_stepping (ecs
);
3898 if (execution_direction
== EXEC_REVERSE
)
3900 /* Set a breakpoint at callee's start address.
3901 From there we can step once and be back in the caller. */
3902 struct symtab_and_line sr_sal
;
3904 sr_sal
.pc
= ecs
->stop_func_start
;
3905 insert_step_resume_breakpoint_at_sal (gdbarch
,
3906 sr_sal
, null_frame_id
);
3909 /* Set a breakpoint at callee's return address (the address
3910 at which the caller will resume). */
3911 insert_step_resume_breakpoint_at_caller (frame
);
3917 /* If we're in the return path from a shared library trampoline,
3918 we want to proceed through the trampoline when stepping. */
3919 if (gdbarch_in_solib_return_trampoline (gdbarch
,
3920 stop_pc
, ecs
->stop_func_name
))
3922 /* Determine where this trampoline returns. */
3923 CORE_ADDR real_stop_pc
;
3924 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
3927 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
3929 /* Only proceed through if we know where it's going. */
3932 /* And put the step-breakpoint there and go until there. */
3933 struct symtab_and_line sr_sal
;
3935 init_sal (&sr_sal
); /* initialize to zeroes */
3936 sr_sal
.pc
= real_stop_pc
;
3937 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3939 /* Do not specify what the fp should be when we stop since
3940 on some machines the prologue is where the new fp value
3942 insert_step_resume_breakpoint_at_sal (gdbarch
,
3943 sr_sal
, null_frame_id
);
3945 /* Restart without fiddling with the step ranges or
3952 stop_pc_sal
= find_pc_line (stop_pc
, 0);
3954 /* NOTE: tausq/2004-05-24: This if block used to be done before all
3955 the trampoline processing logic, however, there are some trampolines
3956 that have no names, so we should do trampoline handling first. */
3957 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3958 && ecs
->stop_func_name
== NULL
3959 && stop_pc_sal
.line
== 0)
3962 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
3964 /* The inferior just stepped into, or returned to, an
3965 undebuggable function (where there is no debugging information
3966 and no line number corresponding to the address where the
3967 inferior stopped). Since we want to skip this kind of code,
3968 we keep going until the inferior returns from this
3969 function - unless the user has asked us not to (via
3970 set step-mode) or we no longer know how to get back
3971 to the call site. */
3972 if (step_stop_if_no_debug
3973 || !frame_id_p (frame_unwind_caller_id (frame
)))
3975 /* If we have no line number and the step-stop-if-no-debug
3976 is set, we stop the step so that the user has a chance to
3977 switch in assembly mode. */
3978 ecs
->event_thread
->stop_step
= 1;
3979 print_stop_reason (END_STEPPING_RANGE
, 0);
3980 stop_stepping (ecs
);
3985 /* Set a breakpoint at callee's return address (the address
3986 at which the caller will resume). */
3987 insert_step_resume_breakpoint_at_caller (frame
);
3993 if (ecs
->event_thread
->step_range_end
== 1)
3995 /* It is stepi or nexti. We always want to stop stepping after
3998 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
3999 ecs
->event_thread
->stop_step
= 1;
4000 print_stop_reason (END_STEPPING_RANGE
, 0);
4001 stop_stepping (ecs
);
4005 if (stop_pc_sal
.line
== 0)
4007 /* We have no line number information. That means to stop
4008 stepping (does this always happen right after one instruction,
4009 when we do "s" in a function with no line numbers,
4010 or can this happen as a result of a return or longjmp?). */
4012 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
4013 ecs
->event_thread
->stop_step
= 1;
4014 print_stop_reason (END_STEPPING_RANGE
, 0);
4015 stop_stepping (ecs
);
4019 /* Look for "calls" to inlined functions, part one. If the inline
4020 frame machinery detected some skipped call sites, we have entered
4021 a new inline function. */
4023 if (frame_id_eq (get_frame_id (get_current_frame ()),
4024 ecs
->event_thread
->step_frame_id
)
4025 && inline_skipped_frames (ecs
->ptid
))
4027 struct symtab_and_line call_sal
;
4030 fprintf_unfiltered (gdb_stdlog
,
4031 "infrun: stepped into inlined function\n");
4033 find_frame_sal (get_current_frame (), &call_sal
);
4035 if (ecs
->event_thread
->step_over_calls
!= STEP_OVER_ALL
)
4037 /* For "step", we're going to stop. But if the call site
4038 for this inlined function is on the same source line as
4039 we were previously stepping, go down into the function
4040 first. Otherwise stop at the call site. */
4042 if (call_sal
.line
== ecs
->event_thread
->current_line
4043 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4044 step_into_inline_frame (ecs
->ptid
);
4046 ecs
->event_thread
->stop_step
= 1;
4047 print_stop_reason (END_STEPPING_RANGE
, 0);
4048 stop_stepping (ecs
);
4053 /* For "next", we should stop at the call site if it is on a
4054 different source line. Otherwise continue through the
4055 inlined function. */
4056 if (call_sal
.line
== ecs
->event_thread
->current_line
4057 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4061 ecs
->event_thread
->stop_step
= 1;
4062 print_stop_reason (END_STEPPING_RANGE
, 0);
4063 stop_stepping (ecs
);
4069 /* Look for "calls" to inlined functions, part two. If we are still
4070 in the same real function we were stepping through, but we have
4071 to go further up to find the exact frame ID, we are stepping
4072 through a more inlined call beyond its call site. */
4074 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
4075 && !frame_id_eq (get_frame_id (get_current_frame ()),
4076 ecs
->event_thread
->step_frame_id
)
4077 && stepped_in_from (get_current_frame (),
4078 ecs
->event_thread
->step_frame_id
))
4081 fprintf_unfiltered (gdb_stdlog
,
4082 "infrun: stepping through inlined function\n");
4084 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
4088 ecs
->event_thread
->stop_step
= 1;
4089 print_stop_reason (END_STEPPING_RANGE
, 0);
4090 stop_stepping (ecs
);
4095 if ((stop_pc
== stop_pc_sal
.pc
)
4096 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
4097 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
4099 /* We are at the start of a different line. So stop. Note that
4100 we don't stop if we step into the middle of a different line.
4101 That is said to make things like for (;;) statements work
4104 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
4105 ecs
->event_thread
->stop_step
= 1;
4106 print_stop_reason (END_STEPPING_RANGE
, 0);
4107 stop_stepping (ecs
);
4111 /* We aren't done stepping.
4113 Optimize by setting the stepping range to the line.
4114 (We might not be in the original line, but if we entered a
4115 new line in mid-statement, we continue stepping. This makes
4116 things like for(;;) statements work better.) */
4118 ecs
->event_thread
->step_range_start
= stop_pc_sal
.pc
;
4119 ecs
->event_thread
->step_range_end
= stop_pc_sal
.end
;
4120 set_step_info (frame
, stop_pc_sal
);
4123 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
4127 /* Is thread TP in the middle of single-stepping? */
4130 currently_stepping (struct thread_info
*tp
)
4132 return ((tp
->step_range_end
&& tp
->step_resume_breakpoint
== NULL
)
4133 || tp
->trap_expected
4134 || tp
->stepping_through_solib_after_catch
4135 || bpstat_should_step ());
4138 /* Returns true if any thread *but* the one passed in "data" is in the
4139 middle of stepping or of handling a "next". */
4142 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
4147 return (tp
->step_range_end
4148 || tp
->trap_expected
4149 || tp
->stepping_through_solib_after_catch
);
4152 /* Inferior has stepped into a subroutine call with source code that
4153 we should not step over. Do step to the first line of code in
4157 handle_step_into_function (struct gdbarch
*gdbarch
,
4158 struct execution_control_state
*ecs
)
4161 struct symtab_and_line stop_func_sal
, sr_sal
;
4163 s
= find_pc_symtab (stop_pc
);
4164 if (s
&& s
->language
!= language_asm
)
4165 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
4166 ecs
->stop_func_start
);
4168 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4169 /* Use the step_resume_break to step until the end of the prologue,
4170 even if that involves jumps (as it seems to on the vax under
4172 /* If the prologue ends in the middle of a source line, continue to
4173 the end of that source line (if it is still within the function).
4174 Otherwise, just go to end of prologue. */
4175 if (stop_func_sal
.end
4176 && stop_func_sal
.pc
!= ecs
->stop_func_start
4177 && stop_func_sal
.end
< ecs
->stop_func_end
)
4178 ecs
->stop_func_start
= stop_func_sal
.end
;
4180 /* Architectures which require breakpoint adjustment might not be able
4181 to place a breakpoint at the computed address. If so, the test
4182 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
4183 ecs->stop_func_start to an address at which a breakpoint may be
4184 legitimately placed.
4186 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
4187 made, GDB will enter an infinite loop when stepping through
4188 optimized code consisting of VLIW instructions which contain
4189 subinstructions corresponding to different source lines. On
4190 FR-V, it's not permitted to place a breakpoint on any but the
4191 first subinstruction of a VLIW instruction. When a breakpoint is
4192 set, GDB will adjust the breakpoint address to the beginning of
4193 the VLIW instruction. Thus, we need to make the corresponding
4194 adjustment here when computing the stop address. */
4196 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
4198 ecs
->stop_func_start
4199 = gdbarch_adjust_breakpoint_address (gdbarch
,
4200 ecs
->stop_func_start
);
4203 if (ecs
->stop_func_start
== stop_pc
)
4205 /* We are already there: stop now. */
4206 ecs
->event_thread
->stop_step
= 1;
4207 print_stop_reason (END_STEPPING_RANGE
, 0);
4208 stop_stepping (ecs
);
4213 /* Put the step-breakpoint there and go until there. */
4214 init_sal (&sr_sal
); /* initialize to zeroes */
4215 sr_sal
.pc
= ecs
->stop_func_start
;
4216 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
4218 /* Do not specify what the fp should be when we stop since on
4219 some machines the prologue is where the new fp value is
4221 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
4223 /* And make sure stepping stops right away then. */
4224 ecs
->event_thread
->step_range_end
= ecs
->event_thread
->step_range_start
;
4229 /* Inferior has stepped backward into a subroutine call with source
4230 code that we should not step over. Do step to the beginning of the
4231 last line of code in it. */
4234 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
4235 struct execution_control_state
*ecs
)
4238 struct symtab_and_line stop_func_sal
, sr_sal
;
4240 s
= find_pc_symtab (stop_pc
);
4241 if (s
&& s
->language
!= language_asm
)
4242 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
4243 ecs
->stop_func_start
);
4245 stop_func_sal
= find_pc_line (stop_pc
, 0);
4247 /* OK, we're just going to keep stepping here. */
4248 if (stop_func_sal
.pc
== stop_pc
)
4250 /* We're there already. Just stop stepping now. */
4251 ecs
->event_thread
->stop_step
= 1;
4252 print_stop_reason (END_STEPPING_RANGE
, 0);
4253 stop_stepping (ecs
);
4257 /* Else just reset the step range and keep going.
4258 No step-resume breakpoint, they don't work for
4259 epilogues, which can have multiple entry paths. */
4260 ecs
->event_thread
->step_range_start
= stop_func_sal
.pc
;
4261 ecs
->event_thread
->step_range_end
= stop_func_sal
.end
;
4267 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
4268 This is used to both functions and to skip over code. */
4271 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
4272 struct symtab_and_line sr_sal
,
4273 struct frame_id sr_id
)
4275 /* There should never be more than one step-resume or longjmp-resume
4276 breakpoint per thread, so we should never be setting a new
4277 step_resume_breakpoint when one is already active. */
4278 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
4281 fprintf_unfiltered (gdb_stdlog
,
4282 "infrun: inserting step-resume breakpoint at 0x%s\n",
4283 paddr_nz (sr_sal
.pc
));
4285 inferior_thread ()->step_resume_breakpoint
4286 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, bp_step_resume
);
4289 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
4290 to skip a potential signal handler.
4292 This is called with the interrupted function's frame. The signal
4293 handler, when it returns, will resume the interrupted function at
4297 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
4299 struct symtab_and_line sr_sal
;
4300 struct gdbarch
*gdbarch
;
4302 gdb_assert (return_frame
!= NULL
);
4303 init_sal (&sr_sal
); /* initialize to zeros */
4305 gdbarch
= get_frame_arch (return_frame
);
4306 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
4307 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4309 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
4310 get_stack_frame_id (return_frame
));
4313 /* Similar to insert_step_resume_breakpoint_at_frame, except
4314 but a breakpoint at the previous frame's PC. This is used to
4315 skip a function after stepping into it (for "next" or if the called
4316 function has no debugging information).
4318 The current function has almost always been reached by single
4319 stepping a call or return instruction. NEXT_FRAME belongs to the
4320 current function, and the breakpoint will be set at the caller's
4323 This is a separate function rather than reusing
4324 insert_step_resume_breakpoint_at_frame in order to avoid
4325 get_prev_frame, which may stop prematurely (see the implementation
4326 of frame_unwind_caller_id for an example). */
4329 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
4331 struct symtab_and_line sr_sal
;
4332 struct gdbarch
*gdbarch
;
4334 /* We shouldn't have gotten here if we don't know where the call site
4336 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
4338 init_sal (&sr_sal
); /* initialize to zeros */
4340 gdbarch
= frame_unwind_caller_arch (next_frame
);
4341 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
4342 frame_unwind_caller_pc (next_frame
));
4343 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4345 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
4346 frame_unwind_caller_id (next_frame
));
4349 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
4350 new breakpoint at the target of a jmp_buf. The handling of
4351 longjmp-resume uses the same mechanisms used for handling
4352 "step-resume" breakpoints. */
4355 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
4357 /* There should never be more than one step-resume or longjmp-resume
4358 breakpoint per thread, so we should never be setting a new
4359 longjmp_resume_breakpoint when one is already active. */
4360 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
4363 fprintf_unfiltered (gdb_stdlog
,
4364 "infrun: inserting longjmp-resume breakpoint at 0x%s\n",
4367 inferior_thread ()->step_resume_breakpoint
=
4368 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
4372 stop_stepping (struct execution_control_state
*ecs
)
4375 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
4377 /* Let callers know we don't want to wait for the inferior anymore. */
4378 ecs
->wait_some_more
= 0;
4381 /* This function handles various cases where we need to continue
4382 waiting for the inferior. */
4383 /* (Used to be the keep_going: label in the old wait_for_inferior) */
4386 keep_going (struct execution_control_state
*ecs
)
4388 /* Save the pc before execution, to compare with pc after stop. */
4389 ecs
->event_thread
->prev_pc
4390 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
4392 /* If we did not do break;, it means we should keep running the
4393 inferior and not return to debugger. */
4395 if (ecs
->event_thread
->trap_expected
4396 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
4398 /* We took a signal (which we are supposed to pass through to
4399 the inferior, else we'd not get here) and we haven't yet
4400 gotten our trap. Simply continue. */
4401 resume (currently_stepping (ecs
->event_thread
),
4402 ecs
->event_thread
->stop_signal
);
4406 /* Either the trap was not expected, but we are continuing
4407 anyway (the user asked that this signal be passed to the
4410 The signal was SIGTRAP, e.g. it was our signal, but we
4411 decided we should resume from it.
4413 We're going to run this baby now!
4415 Note that insert_breakpoints won't try to re-insert
4416 already inserted breakpoints. Therefore, we don't
4417 care if breakpoints were already inserted, or not. */
4419 if (ecs
->event_thread
->stepping_over_breakpoint
)
4421 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
4422 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
4423 /* Since we can't do a displaced step, we have to remove
4424 the breakpoint while we step it. To keep things
4425 simple, we remove them all. */
4426 remove_breakpoints ();
4430 struct gdb_exception e
;
4431 /* Stop stepping when inserting breakpoints
4433 TRY_CATCH (e
, RETURN_MASK_ERROR
)
4435 insert_breakpoints ();
4439 stop_stepping (ecs
);
4444 ecs
->event_thread
->trap_expected
= ecs
->event_thread
->stepping_over_breakpoint
;
4446 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
4447 specifies that such a signal should be delivered to the
4450 Typically, this would occure when a user is debugging a
4451 target monitor on a simulator: the target monitor sets a
4452 breakpoint; the simulator encounters this break-point and
4453 halts the simulation handing control to GDB; GDB, noteing
4454 that the break-point isn't valid, returns control back to the
4455 simulator; the simulator then delivers the hardware
4456 equivalent of a SIGNAL_TRAP to the program being debugged. */
4458 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
4459 && !signal_program
[ecs
->event_thread
->stop_signal
])
4460 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
4462 resume (currently_stepping (ecs
->event_thread
),
4463 ecs
->event_thread
->stop_signal
);
4466 prepare_to_wait (ecs
);
4469 /* This function normally comes after a resume, before
4470 handle_inferior_event exits. It takes care of any last bits of
4471 housekeeping, and sets the all-important wait_some_more flag. */
4474 prepare_to_wait (struct execution_control_state
*ecs
)
4477 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
4478 if (infwait_state
== infwait_normal_state
)
4480 overlay_cache_invalid
= 1;
4482 /* We have to invalidate the registers BEFORE calling
4483 target_wait because they can be loaded from the target while
4484 in target_wait. This makes remote debugging a bit more
4485 efficient for those targets that provide critical registers
4486 as part of their normal status mechanism. */
4488 registers_changed ();
4489 waiton_ptid
= pid_to_ptid (-1);
4491 /* This is the old end of the while loop. Let everybody know we
4492 want to wait for the inferior some more and get called again
4494 ecs
->wait_some_more
= 1;
4497 /* Print why the inferior has stopped. We always print something when
4498 the inferior exits, or receives a signal. The rest of the cases are
4499 dealt with later on in normal_stop() and print_it_typical(). Ideally
4500 there should be a call to this function from handle_inferior_event()
4501 each time stop_stepping() is called.*/
4503 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
4505 switch (stop_reason
)
4507 case END_STEPPING_RANGE
:
4508 /* We are done with a step/next/si/ni command. */
4509 /* For now print nothing. */
4510 /* Print a message only if not in the middle of doing a "step n"
4511 operation for n > 1 */
4512 if (!inferior_thread ()->step_multi
4513 || !inferior_thread ()->stop_step
)
4514 if (ui_out_is_mi_like_p (uiout
))
4517 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
4520 /* The inferior was terminated by a signal. */
4521 annotate_signalled ();
4522 if (ui_out_is_mi_like_p (uiout
))
4525 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
4526 ui_out_text (uiout
, "\nProgram terminated with signal ");
4527 annotate_signal_name ();
4528 ui_out_field_string (uiout
, "signal-name",
4529 target_signal_to_name (stop_info
));
4530 annotate_signal_name_end ();
4531 ui_out_text (uiout
, ", ");
4532 annotate_signal_string ();
4533 ui_out_field_string (uiout
, "signal-meaning",
4534 target_signal_to_string (stop_info
));
4535 annotate_signal_string_end ();
4536 ui_out_text (uiout
, ".\n");
4537 ui_out_text (uiout
, "The program no longer exists.\n");
4540 /* The inferior program is finished. */
4541 annotate_exited (stop_info
);
4544 if (ui_out_is_mi_like_p (uiout
))
4545 ui_out_field_string (uiout
, "reason",
4546 async_reason_lookup (EXEC_ASYNC_EXITED
));
4547 ui_out_text (uiout
, "\nProgram exited with code ");
4548 ui_out_field_fmt (uiout
, "exit-code", "0%o",
4549 (unsigned int) stop_info
);
4550 ui_out_text (uiout
, ".\n");
4554 if (ui_out_is_mi_like_p (uiout
))
4557 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
4558 ui_out_text (uiout
, "\nProgram exited normally.\n");
4560 /* Support the --return-child-result option. */
4561 return_child_result_value
= stop_info
;
4563 case SIGNAL_RECEIVED
:
4564 /* Signal received. The signal table tells us to print about
4568 if (stop_info
== TARGET_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
4570 struct thread_info
*t
= inferior_thread ();
4572 ui_out_text (uiout
, "\n[");
4573 ui_out_field_string (uiout
, "thread-name",
4574 target_pid_to_str (t
->ptid
));
4575 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
4576 ui_out_text (uiout
, " stopped");
4580 ui_out_text (uiout
, "\nProgram received signal ");
4581 annotate_signal_name ();
4582 if (ui_out_is_mi_like_p (uiout
))
4584 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
4585 ui_out_field_string (uiout
, "signal-name",
4586 target_signal_to_name (stop_info
));
4587 annotate_signal_name_end ();
4588 ui_out_text (uiout
, ", ");
4589 annotate_signal_string ();
4590 ui_out_field_string (uiout
, "signal-meaning",
4591 target_signal_to_string (stop_info
));
4592 annotate_signal_string_end ();
4594 ui_out_text (uiout
, ".\n");
4597 /* Reverse execution: target ran out of history info. */
4598 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
4601 internal_error (__FILE__
, __LINE__
,
4602 _("print_stop_reason: unrecognized enum value"));
4608 /* Here to return control to GDB when the inferior stops for real.
4609 Print appropriate messages, remove breakpoints, give terminal our modes.
4611 STOP_PRINT_FRAME nonzero means print the executing frame
4612 (pc, function, args, file, line number and line text).
4613 BREAKPOINTS_FAILED nonzero means stop was due to error
4614 attempting to insert breakpoints. */
4619 struct target_waitstatus last
;
4621 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
4623 get_last_target_status (&last_ptid
, &last
);
4625 /* If an exception is thrown from this point on, make sure to
4626 propagate GDB's knowledge of the executing state to the
4627 frontend/user running state. A QUIT is an easy exception to see
4628 here, so do this before any filtered output. */
4630 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
4631 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
4632 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4633 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
4635 /* In non-stop mode, we don't want GDB to switch threads behind the
4636 user's back, to avoid races where the user is typing a command to
4637 apply to thread x, but GDB switches to thread y before the user
4638 finishes entering the command. */
4640 /* As with the notification of thread events, we want to delay
4641 notifying the user that we've switched thread context until
4642 the inferior actually stops.
4644 There's no point in saying anything if the inferior has exited.
4645 Note that SIGNALLED here means "exited with a signal", not
4646 "received a signal". */
4648 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
4649 && target_has_execution
4650 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
4651 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4653 target_terminal_ours_for_output ();
4654 printf_filtered (_("[Switching to %s]\n"),
4655 target_pid_to_str (inferior_ptid
));
4656 annotate_thread_changed ();
4657 previous_inferior_ptid
= inferior_ptid
;
4660 if (!breakpoints_always_inserted_mode () && target_has_execution
)
4662 if (remove_breakpoints ())
4664 target_terminal_ours_for_output ();
4665 printf_filtered (_("\
4666 Cannot remove breakpoints because program is no longer writable.\n\
4667 Further execution is probably impossible.\n"));
4671 /* If an auto-display called a function and that got a signal,
4672 delete that auto-display to avoid an infinite recursion. */
4674 if (stopped_by_random_signal
)
4675 disable_current_display ();
4677 /* Don't print a message if in the middle of doing a "step n"
4678 operation for n > 1 */
4679 if (target_has_execution
4680 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
4681 && last
.kind
!= TARGET_WAITKIND_EXITED
4682 && inferior_thread ()->step_multi
4683 && inferior_thread ()->stop_step
)
4686 target_terminal_ours ();
4688 /* Set the current source location. This will also happen if we
4689 display the frame below, but the current SAL will be incorrect
4690 during a user hook-stop function. */
4691 if (has_stack_frames () && !stop_stack_dummy
)
4692 set_current_sal_from_frame (get_current_frame (), 1);
4694 /* Let the user/frontend see the threads as stopped. */
4695 do_cleanups (old_chain
);
4697 /* Look up the hook_stop and run it (CLI internally handles problem
4698 of stop_command's pre-hook not existing). */
4700 catch_errors (hook_stop_stub
, stop_command
,
4701 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
4703 if (!has_stack_frames ())
4706 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
4707 || last
.kind
== TARGET_WAITKIND_EXITED
)
4710 /* Select innermost stack frame - i.e., current frame is frame 0,
4711 and current location is based on that.
4712 Don't do this on return from a stack dummy routine,
4713 or if the program has exited. */
4715 if (!stop_stack_dummy
)
4717 select_frame (get_current_frame ());
4719 /* Print current location without a level number, if
4720 we have changed functions or hit a breakpoint.
4721 Print source line if we have one.
4722 bpstat_print() contains the logic deciding in detail
4723 what to print, based on the event(s) that just occurred. */
4725 /* If --batch-silent is enabled then there's no need to print the current
4726 source location, and to try risks causing an error message about
4727 missing source files. */
4728 if (stop_print_frame
&& !batch_silent
)
4732 int do_frame_printing
= 1;
4733 struct thread_info
*tp
= inferior_thread ();
4735 bpstat_ret
= bpstat_print (tp
->stop_bpstat
);
4739 /* If we had hit a shared library event breakpoint,
4740 bpstat_print would print out this message. If we hit
4741 an OS-level shared library event, do the same
4743 if (last
.kind
== TARGET_WAITKIND_LOADED
)
4745 printf_filtered (_("Stopped due to shared library event\n"));
4746 source_flag
= SRC_LINE
; /* something bogus */
4747 do_frame_printing
= 0;
4751 /* FIXME: cagney/2002-12-01: Given that a frame ID does
4752 (or should) carry around the function and does (or
4753 should) use that when doing a frame comparison. */
4755 && frame_id_eq (tp
->step_frame_id
,
4756 get_frame_id (get_current_frame ()))
4757 && step_start_function
== find_pc_function (stop_pc
))
4758 source_flag
= SRC_LINE
; /* finished step, just print source line */
4760 source_flag
= SRC_AND_LOC
; /* print location and source line */
4762 case PRINT_SRC_AND_LOC
:
4763 source_flag
= SRC_AND_LOC
; /* print location and source line */
4765 case PRINT_SRC_ONLY
:
4766 source_flag
= SRC_LINE
;
4769 source_flag
= SRC_LINE
; /* something bogus */
4770 do_frame_printing
= 0;
4773 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
4776 /* The behavior of this routine with respect to the source
4778 SRC_LINE: Print only source line
4779 LOCATION: Print only location
4780 SRC_AND_LOC: Print location and source line */
4781 if (do_frame_printing
)
4782 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
4784 /* Display the auto-display expressions. */
4789 /* Save the function value return registers, if we care.
4790 We might be about to restore their previous contents. */
4791 if (inferior_thread ()->proceed_to_finish
)
4793 /* This should not be necessary. */
4795 regcache_xfree (stop_registers
);
4797 /* NB: The copy goes through to the target picking up the value of
4798 all the registers. */
4799 stop_registers
= regcache_dup (get_current_regcache ());
4802 if (stop_stack_dummy
)
4804 /* Pop the empty frame that contains the stack dummy.
4805 This also restores inferior state prior to the call
4806 (struct inferior_thread_state). */
4807 struct frame_info
*frame
= get_current_frame ();
4808 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
4810 /* frame_pop() calls reinit_frame_cache as the last thing it does
4811 which means there's currently no selected frame. We don't need
4812 to re-establish a selected frame if the dummy call returns normally,
4813 that will be done by restore_inferior_status. However, we do have
4814 to handle the case where the dummy call is returning after being
4815 stopped (e.g. the dummy call previously hit a breakpoint). We
4816 can't know which case we have so just always re-establish a
4817 selected frame here. */
4818 select_frame (get_current_frame ());
4822 annotate_stopped ();
4824 /* Suppress the stop observer if we're in the middle of:
4826 - a step n (n > 1), as there still more steps to be done.
4828 - a "finish" command, as the observer will be called in
4829 finish_command_continuation, so it can include the inferior
4830 function's return value.
4832 - calling an inferior function, as we pretend we inferior didn't
4833 run at all. The return value of the call is handled by the
4834 expression evaluator, through call_function_by_hand. */
4836 if (!target_has_execution
4837 || last
.kind
== TARGET_WAITKIND_SIGNALLED
4838 || last
.kind
== TARGET_WAITKIND_EXITED
4839 || (!inferior_thread ()->step_multi
4840 && !(inferior_thread ()->stop_bpstat
4841 && inferior_thread ()->proceed_to_finish
)
4842 && !inferior_thread ()->in_infcall
))
4844 if (!ptid_equal (inferior_ptid
, null_ptid
))
4845 observer_notify_normal_stop (inferior_thread ()->stop_bpstat
,
4848 observer_notify_normal_stop (NULL
, stop_print_frame
);
4851 if (target_has_execution
)
4853 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
4854 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4855 /* Delete the breakpoint we stopped at, if it wants to be deleted.
4856 Delete any breakpoint that is to be deleted at the next stop. */
4857 breakpoint_auto_delete (inferior_thread ()->stop_bpstat
);
4862 hook_stop_stub (void *cmd
)
4864 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
4869 signal_stop_state (int signo
)
4871 return signal_stop
[signo
];
4875 signal_print_state (int signo
)
4877 return signal_print
[signo
];
4881 signal_pass_state (int signo
)
4883 return signal_program
[signo
];
4887 signal_stop_update (int signo
, int state
)
4889 int ret
= signal_stop
[signo
];
4890 signal_stop
[signo
] = state
;
4895 signal_print_update (int signo
, int state
)
4897 int ret
= signal_print
[signo
];
4898 signal_print
[signo
] = state
;
4903 signal_pass_update (int signo
, int state
)
4905 int ret
= signal_program
[signo
];
4906 signal_program
[signo
] = state
;
4911 sig_print_header (void)
4913 printf_filtered (_("\
4914 Signal Stop\tPrint\tPass to program\tDescription\n"));
4918 sig_print_info (enum target_signal oursig
)
4920 const char *name
= target_signal_to_name (oursig
);
4921 int name_padding
= 13 - strlen (name
);
4923 if (name_padding
<= 0)
4926 printf_filtered ("%s", name
);
4927 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
4928 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
4929 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
4930 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
4931 printf_filtered ("%s\n", target_signal_to_string (oursig
));
4934 /* Specify how various signals in the inferior should be handled. */
4937 handle_command (char *args
, int from_tty
)
4940 int digits
, wordlen
;
4941 int sigfirst
, signum
, siglast
;
4942 enum target_signal oursig
;
4945 unsigned char *sigs
;
4946 struct cleanup
*old_chain
;
4950 error_no_arg (_("signal to handle"));
4953 /* Allocate and zero an array of flags for which signals to handle. */
4955 nsigs
= (int) TARGET_SIGNAL_LAST
;
4956 sigs
= (unsigned char *) alloca (nsigs
);
4957 memset (sigs
, 0, nsigs
);
4959 /* Break the command line up into args. */
4961 argv
= gdb_buildargv (args
);
4962 old_chain
= make_cleanup_freeargv (argv
);
4964 /* Walk through the args, looking for signal oursigs, signal names, and
4965 actions. Signal numbers and signal names may be interspersed with
4966 actions, with the actions being performed for all signals cumulatively
4967 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
4969 while (*argv
!= NULL
)
4971 wordlen
= strlen (*argv
);
4972 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
4976 sigfirst
= siglast
= -1;
4978 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
4980 /* Apply action to all signals except those used by the
4981 debugger. Silently skip those. */
4984 siglast
= nsigs
- 1;
4986 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
4988 SET_SIGS (nsigs
, sigs
, signal_stop
);
4989 SET_SIGS (nsigs
, sigs
, signal_print
);
4991 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
4993 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4995 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
4997 SET_SIGS (nsigs
, sigs
, signal_print
);
4999 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
5001 SET_SIGS (nsigs
, sigs
, signal_program
);
5003 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
5005 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
5007 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
5009 SET_SIGS (nsigs
, sigs
, signal_program
);
5011 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
5013 UNSET_SIGS (nsigs
, sigs
, signal_print
);
5014 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
5016 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
5018 UNSET_SIGS (nsigs
, sigs
, signal_program
);
5020 else if (digits
> 0)
5022 /* It is numeric. The numeric signal refers to our own
5023 internal signal numbering from target.h, not to host/target
5024 signal number. This is a feature; users really should be
5025 using symbolic names anyway, and the common ones like
5026 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
5028 sigfirst
= siglast
= (int)
5029 target_signal_from_command (atoi (*argv
));
5030 if ((*argv
)[digits
] == '-')
5033 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
5035 if (sigfirst
> siglast
)
5037 /* Bet he didn't figure we'd think of this case... */
5045 oursig
= target_signal_from_name (*argv
);
5046 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
5048 sigfirst
= siglast
= (int) oursig
;
5052 /* Not a number and not a recognized flag word => complain. */
5053 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
5057 /* If any signal numbers or symbol names were found, set flags for
5058 which signals to apply actions to. */
5060 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
5062 switch ((enum target_signal
) signum
)
5064 case TARGET_SIGNAL_TRAP
:
5065 case TARGET_SIGNAL_INT
:
5066 if (!allsigs
&& !sigs
[signum
])
5068 if (query (_("%s is used by the debugger.\n\
5069 Are you sure you want to change it? "), target_signal_to_name ((enum target_signal
) signum
)))
5075 printf_unfiltered (_("Not confirmed, unchanged.\n"));
5076 gdb_flush (gdb_stdout
);
5080 case TARGET_SIGNAL_0
:
5081 case TARGET_SIGNAL_DEFAULT
:
5082 case TARGET_SIGNAL_UNKNOWN
:
5083 /* Make sure that "all" doesn't print these. */
5094 for (signum
= 0; signum
< nsigs
; signum
++)
5097 target_notice_signals (inferior_ptid
);
5101 /* Show the results. */
5102 sig_print_header ();
5103 for (; signum
< nsigs
; signum
++)
5105 sig_print_info (signum
);
5111 do_cleanups (old_chain
);
5115 xdb_handle_command (char *args
, int from_tty
)
5118 struct cleanup
*old_chain
;
5121 error_no_arg (_("xdb command"));
5123 /* Break the command line up into args. */
5125 argv
= gdb_buildargv (args
);
5126 old_chain
= make_cleanup_freeargv (argv
);
5127 if (argv
[1] != (char *) NULL
)
5132 bufLen
= strlen (argv
[0]) + 20;
5133 argBuf
= (char *) xmalloc (bufLen
);
5137 enum target_signal oursig
;
5139 oursig
= target_signal_from_name (argv
[0]);
5140 memset (argBuf
, 0, bufLen
);
5141 if (strcmp (argv
[1], "Q") == 0)
5142 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
5145 if (strcmp (argv
[1], "s") == 0)
5147 if (!signal_stop
[oursig
])
5148 sprintf (argBuf
, "%s %s", argv
[0], "stop");
5150 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
5152 else if (strcmp (argv
[1], "i") == 0)
5154 if (!signal_program
[oursig
])
5155 sprintf (argBuf
, "%s %s", argv
[0], "pass");
5157 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
5159 else if (strcmp (argv
[1], "r") == 0)
5161 if (!signal_print
[oursig
])
5162 sprintf (argBuf
, "%s %s", argv
[0], "print");
5164 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
5170 handle_command (argBuf
, from_tty
);
5172 printf_filtered (_("Invalid signal handling flag.\n"));
5177 do_cleanups (old_chain
);
5180 /* Print current contents of the tables set by the handle command.
5181 It is possible we should just be printing signals actually used
5182 by the current target (but for things to work right when switching
5183 targets, all signals should be in the signal tables). */
5186 signals_info (char *signum_exp
, int from_tty
)
5188 enum target_signal oursig
;
5189 sig_print_header ();
5193 /* First see if this is a symbol name. */
5194 oursig
= target_signal_from_name (signum_exp
);
5195 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
5197 /* No, try numeric. */
5199 target_signal_from_command (parse_and_eval_long (signum_exp
));
5201 sig_print_info (oursig
);
5205 printf_filtered ("\n");
5206 /* These ugly casts brought to you by the native VAX compiler. */
5207 for (oursig
= TARGET_SIGNAL_FIRST
;
5208 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
5209 oursig
= (enum target_signal
) ((int) oursig
+ 1))
5213 if (oursig
!= TARGET_SIGNAL_UNKNOWN
5214 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
5215 sig_print_info (oursig
);
5218 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
5221 /* The $_siginfo convenience variable is a bit special. We don't know
5222 for sure the type of the value until we actually have a chance to
5223 fetch the data. The type can change depending on gdbarch, so it it
5224 also dependent on which thread you have selected.
5226 1. making $_siginfo be an internalvar that creates a new value on
5229 2. making the value of $_siginfo be an lval_computed value. */
5231 /* This function implements the lval_computed support for reading a
5235 siginfo_value_read (struct value
*v
)
5237 LONGEST transferred
;
5240 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
5242 value_contents_all_raw (v
),
5244 TYPE_LENGTH (value_type (v
)));
5246 if (transferred
!= TYPE_LENGTH (value_type (v
)))
5247 error (_("Unable to read siginfo"));
5250 /* This function implements the lval_computed support for writing a
5254 siginfo_value_write (struct value
*v
, struct value
*fromval
)
5256 LONGEST transferred
;
5258 transferred
= target_write (¤t_target
,
5259 TARGET_OBJECT_SIGNAL_INFO
,
5261 value_contents_all_raw (fromval
),
5263 TYPE_LENGTH (value_type (fromval
)));
5265 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
5266 error (_("Unable to write siginfo"));
5269 static struct lval_funcs siginfo_value_funcs
=
5275 /* Return a new value with the correct type for the siginfo object of
5276 the current thread using architecture GDBARCH. Return a void value
5277 if there's no object available. */
5279 static struct value
*
5280 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
)
5282 if (target_has_stack
5283 && !ptid_equal (inferior_ptid
, null_ptid
)
5284 && gdbarch_get_siginfo_type_p (gdbarch
))
5286 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
5287 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
5290 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
5294 /* Inferior thread state.
5295 These are details related to the inferior itself, and don't include
5296 things like what frame the user had selected or what gdb was doing
5297 with the target at the time.
5298 For inferior function calls these are things we want to restore
5299 regardless of whether the function call successfully completes
5300 or the dummy frame has to be manually popped. */
5302 struct inferior_thread_state
5304 enum target_signal stop_signal
;
5306 struct regcache
*registers
;
5309 struct inferior_thread_state
*
5310 save_inferior_thread_state (void)
5312 struct inferior_thread_state
*inf_state
= XMALLOC (struct inferior_thread_state
);
5313 struct thread_info
*tp
= inferior_thread ();
5315 inf_state
->stop_signal
= tp
->stop_signal
;
5316 inf_state
->stop_pc
= stop_pc
;
5318 inf_state
->registers
= regcache_dup (get_current_regcache ());
5323 /* Restore inferior session state to INF_STATE. */
5326 restore_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5328 struct thread_info
*tp
= inferior_thread ();
5330 tp
->stop_signal
= inf_state
->stop_signal
;
5331 stop_pc
= inf_state
->stop_pc
;
5333 /* The inferior can be gone if the user types "print exit(0)"
5334 (and perhaps other times). */
5335 if (target_has_execution
)
5336 /* NB: The register write goes through to the target. */
5337 regcache_cpy (get_current_regcache (), inf_state
->registers
);
5338 regcache_xfree (inf_state
->registers
);
5343 do_restore_inferior_thread_state_cleanup (void *state
)
5345 restore_inferior_thread_state (state
);
5349 make_cleanup_restore_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5351 return make_cleanup (do_restore_inferior_thread_state_cleanup
, inf_state
);
5355 discard_inferior_thread_state (struct inferior_thread_state
*inf_state
)
5357 regcache_xfree (inf_state
->registers
);
5362 get_inferior_thread_state_regcache (struct inferior_thread_state
*inf_state
)
5364 return inf_state
->registers
;
5367 /* Session related state for inferior function calls.
5368 These are the additional bits of state that need to be restored
5369 when an inferior function call successfully completes. */
5371 struct inferior_status
5375 int stop_stack_dummy
;
5376 int stopped_by_random_signal
;
5377 int stepping_over_breakpoint
;
5378 CORE_ADDR step_range_start
;
5379 CORE_ADDR step_range_end
;
5380 struct frame_id step_frame_id
;
5381 struct frame_id step_stack_frame_id
;
5382 enum step_over_calls_kind step_over_calls
;
5383 CORE_ADDR step_resume_break_address
;
5384 int stop_after_trap
;
5387 /* ID if the selected frame when the inferior function call was made. */
5388 struct frame_id selected_frame_id
;
5390 int proceed_to_finish
;
5394 /* Save all of the information associated with the inferior<==>gdb
5397 struct inferior_status
*
5398 save_inferior_status (void)
5400 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
5401 struct thread_info
*tp
= inferior_thread ();
5402 struct inferior
*inf
= current_inferior ();
5404 inf_status
->stop_step
= tp
->stop_step
;
5405 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
5406 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
5407 inf_status
->stepping_over_breakpoint
= tp
->trap_expected
;
5408 inf_status
->step_range_start
= tp
->step_range_start
;
5409 inf_status
->step_range_end
= tp
->step_range_end
;
5410 inf_status
->step_frame_id
= tp
->step_frame_id
;
5411 inf_status
->step_stack_frame_id
= tp
->step_stack_frame_id
;
5412 inf_status
->step_over_calls
= tp
->step_over_calls
;
5413 inf_status
->stop_after_trap
= stop_after_trap
;
5414 inf_status
->stop_soon
= inf
->stop_soon
;
5415 /* Save original bpstat chain here; replace it with copy of chain.
5416 If caller's caller is walking the chain, they'll be happier if we
5417 hand them back the original chain when restore_inferior_status is
5419 inf_status
->stop_bpstat
= tp
->stop_bpstat
;
5420 tp
->stop_bpstat
= bpstat_copy (tp
->stop_bpstat
);
5421 inf_status
->proceed_to_finish
= tp
->proceed_to_finish
;
5422 inf_status
->in_infcall
= tp
->in_infcall
;
5424 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
5430 restore_selected_frame (void *args
)
5432 struct frame_id
*fid
= (struct frame_id
*) args
;
5433 struct frame_info
*frame
;
5435 frame
= frame_find_by_id (*fid
);
5437 /* If inf_status->selected_frame_id is NULL, there was no previously
5441 warning (_("Unable to restore previously selected frame."));
5445 select_frame (frame
);
5450 /* Restore inferior session state to INF_STATUS. */
5453 restore_inferior_status (struct inferior_status
*inf_status
)
5455 struct thread_info
*tp
= inferior_thread ();
5456 struct inferior
*inf
= current_inferior ();
5458 tp
->stop_step
= inf_status
->stop_step
;
5459 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
5460 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
5461 tp
->trap_expected
= inf_status
->stepping_over_breakpoint
;
5462 tp
->step_range_start
= inf_status
->step_range_start
;
5463 tp
->step_range_end
= inf_status
->step_range_end
;
5464 tp
->step_frame_id
= inf_status
->step_frame_id
;
5465 tp
->step_stack_frame_id
= inf_status
->step_stack_frame_id
;
5466 tp
->step_over_calls
= inf_status
->step_over_calls
;
5467 stop_after_trap
= inf_status
->stop_after_trap
;
5468 inf
->stop_soon
= inf_status
->stop_soon
;
5469 bpstat_clear (&tp
->stop_bpstat
);
5470 tp
->stop_bpstat
= inf_status
->stop_bpstat
;
5471 inf_status
->stop_bpstat
= NULL
;
5472 tp
->proceed_to_finish
= inf_status
->proceed_to_finish
;
5473 tp
->in_infcall
= inf_status
->in_infcall
;
5475 if (target_has_stack
)
5477 /* The point of catch_errors is that if the stack is clobbered,
5478 walking the stack might encounter a garbage pointer and
5479 error() trying to dereference it. */
5481 (restore_selected_frame
, &inf_status
->selected_frame_id
,
5482 "Unable to restore previously selected frame:\n",
5483 RETURN_MASK_ERROR
) == 0)
5484 /* Error in restoring the selected frame. Select the innermost
5486 select_frame (get_current_frame ());
5493 do_restore_inferior_status_cleanup (void *sts
)
5495 restore_inferior_status (sts
);
5499 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
5501 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
5505 discard_inferior_status (struct inferior_status
*inf_status
)
5507 /* See save_inferior_status for info on stop_bpstat. */
5508 bpstat_clear (&inf_status
->stop_bpstat
);
5513 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
5515 struct target_waitstatus last
;
5518 get_last_target_status (&last_ptid
, &last
);
5520 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
5523 if (!ptid_equal (last_ptid
, pid
))
5526 *child_pid
= last
.value
.related_pid
;
5531 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
5533 struct target_waitstatus last
;
5536 get_last_target_status (&last_ptid
, &last
);
5538 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
5541 if (!ptid_equal (last_ptid
, pid
))
5544 *child_pid
= last
.value
.related_pid
;
5549 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
5551 struct target_waitstatus last
;
5554 get_last_target_status (&last_ptid
, &last
);
5556 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
5559 if (!ptid_equal (last_ptid
, pid
))
5562 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
5566 /* Oft used ptids */
5568 ptid_t minus_one_ptid
;
5570 /* Create a ptid given the necessary PID, LWP, and TID components. */
5573 ptid_build (int pid
, long lwp
, long tid
)
5583 /* Create a ptid from just a pid. */
5586 pid_to_ptid (int pid
)
5588 return ptid_build (pid
, 0, 0);
5591 /* Fetch the pid (process id) component from a ptid. */
5594 ptid_get_pid (ptid_t ptid
)
5599 /* Fetch the lwp (lightweight process) component from a ptid. */
5602 ptid_get_lwp (ptid_t ptid
)
5607 /* Fetch the tid (thread id) component from a ptid. */
5610 ptid_get_tid (ptid_t ptid
)
5615 /* ptid_equal() is used to test equality of two ptids. */
5618 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
5620 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
5621 && ptid1
.tid
== ptid2
.tid
);
5624 /* Returns true if PTID represents a process. */
5627 ptid_is_pid (ptid_t ptid
)
5629 if (ptid_equal (minus_one_ptid
, ptid
))
5631 if (ptid_equal (null_ptid
, ptid
))
5634 return (ptid_get_lwp (ptid
) == 0 && ptid_get_tid (ptid
) == 0);
5637 /* restore_inferior_ptid() will be used by the cleanup machinery
5638 to restore the inferior_ptid value saved in a call to
5639 save_inferior_ptid(). */
5642 restore_inferior_ptid (void *arg
)
5644 ptid_t
*saved_ptid_ptr
= arg
;
5645 inferior_ptid
= *saved_ptid_ptr
;
5649 /* Save the value of inferior_ptid so that it may be restored by a
5650 later call to do_cleanups(). Returns the struct cleanup pointer
5651 needed for later doing the cleanup. */
5654 save_inferior_ptid (void)
5656 ptid_t
*saved_ptid_ptr
;
5658 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
5659 *saved_ptid_ptr
= inferior_ptid
;
5660 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
5664 /* User interface for reverse debugging:
5665 Set exec-direction / show exec-direction commands
5666 (returns error unless target implements to_set_exec_direction method). */
5668 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
5669 static const char exec_forward
[] = "forward";
5670 static const char exec_reverse
[] = "reverse";
5671 static const char *exec_direction
= exec_forward
;
5672 static const char *exec_direction_names
[] = {
5679 set_exec_direction_func (char *args
, int from_tty
,
5680 struct cmd_list_element
*cmd
)
5682 if (target_can_execute_reverse
)
5684 if (!strcmp (exec_direction
, exec_forward
))
5685 execution_direction
= EXEC_FORWARD
;
5686 else if (!strcmp (exec_direction
, exec_reverse
))
5687 execution_direction
= EXEC_REVERSE
;
5692 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
5693 struct cmd_list_element
*cmd
, const char *value
)
5695 switch (execution_direction
) {
5697 fprintf_filtered (out
, _("Forward.\n"));
5700 fprintf_filtered (out
, _("Reverse.\n"));
5704 fprintf_filtered (out
,
5705 _("Forward (target `%s' does not support exec-direction).\n"),
5711 /* User interface for non-stop mode. */
5714 static int non_stop_1
= 0;
5717 set_non_stop (char *args
, int from_tty
,
5718 struct cmd_list_element
*c
)
5720 if (target_has_execution
)
5722 non_stop_1
= non_stop
;
5723 error (_("Cannot change this setting while the inferior is running."));
5726 non_stop
= non_stop_1
;
5730 show_non_stop (struct ui_file
*file
, int from_tty
,
5731 struct cmd_list_element
*c
, const char *value
)
5733 fprintf_filtered (file
,
5734 _("Controlling the inferior in non-stop mode is %s.\n"),
5739 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
5740 struct cmd_list_element
*c
, const char *value
)
5742 fprintf_filtered (file
, _("\
5743 Resuming the execution of threads of all processes is %s.\n"), value
);
5747 _initialize_infrun (void)
5751 struct cmd_list_element
*c
;
5753 add_info ("signals", signals_info
, _("\
5754 What debugger does when program gets various signals.\n\
5755 Specify a signal as argument to print info on that signal only."));
5756 add_info_alias ("handle", "signals", 0);
5758 add_com ("handle", class_run
, handle_command
, _("\
5759 Specify how to handle a signal.\n\
5760 Args are signals and actions to apply to those signals.\n\
5761 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
5762 from 1-15 are allowed for compatibility with old versions of GDB.\n\
5763 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
5764 The special arg \"all\" is recognized to mean all signals except those\n\
5765 used by the debugger, typically SIGTRAP and SIGINT.\n\
5766 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
5767 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
5768 Stop means reenter debugger if this signal happens (implies print).\n\
5769 Print means print a message if this signal happens.\n\
5770 Pass means let program see this signal; otherwise program doesn't know.\n\
5771 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
5772 Pass and Stop may be combined."));
5775 add_com ("lz", class_info
, signals_info
, _("\
5776 What debugger does when program gets various signals.\n\
5777 Specify a signal as argument to print info on that signal only."));
5778 add_com ("z", class_run
, xdb_handle_command
, _("\
5779 Specify how to handle a signal.\n\
5780 Args are signals and actions to apply to those signals.\n\
5781 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
5782 from 1-15 are allowed for compatibility with old versions of GDB.\n\
5783 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
5784 The special arg \"all\" is recognized to mean all signals except those\n\
5785 used by the debugger, typically SIGTRAP and SIGINT.\n\
5786 Recognized actions include \"s\" (toggles between stop and nostop), \n\
5787 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
5788 nopass), \"Q\" (noprint)\n\
5789 Stop means reenter debugger if this signal happens (implies print).\n\
5790 Print means print a message if this signal happens.\n\
5791 Pass means let program see this signal; otherwise program doesn't know.\n\
5792 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
5793 Pass and Stop may be combined."));
5797 stop_command
= add_cmd ("stop", class_obscure
,
5798 not_just_help_class_command
, _("\
5799 There is no `stop' command, but you can set a hook on `stop'.\n\
5800 This allows you to set a list of commands to be run each time execution\n\
5801 of the program stops."), &cmdlist
);
5803 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
5804 Set inferior debugging."), _("\
5805 Show inferior debugging."), _("\
5806 When non-zero, inferior specific debugging is enabled."),
5809 &setdebuglist
, &showdebuglist
);
5811 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
5812 Set displaced stepping debugging."), _("\
5813 Show displaced stepping debugging."), _("\
5814 When non-zero, displaced stepping specific debugging is enabled."),
5816 show_debug_displaced
,
5817 &setdebuglist
, &showdebuglist
);
5819 add_setshow_boolean_cmd ("non-stop", no_class
,
5821 Set whether gdb controls the inferior in non-stop mode."), _("\
5822 Show whether gdb controls the inferior in non-stop mode."), _("\
5823 When debugging a multi-threaded program and this setting is\n\
5824 off (the default, also called all-stop mode), when one thread stops\n\
5825 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
5826 all other threads in the program while you interact with the thread of\n\
5827 interest. When you continue or step a thread, you can allow the other\n\
5828 threads to run, or have them remain stopped, but while you inspect any\n\
5829 thread's state, all threads stop.\n\
5831 In non-stop mode, when one thread stops, other threads can continue\n\
5832 to run freely. You'll be able to step each thread independently,\n\
5833 leave it stopped or free to run as needed."),
5839 numsigs
= (int) TARGET_SIGNAL_LAST
;
5840 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
5841 signal_print
= (unsigned char *)
5842 xmalloc (sizeof (signal_print
[0]) * numsigs
);
5843 signal_program
= (unsigned char *)
5844 xmalloc (sizeof (signal_program
[0]) * numsigs
);
5845 for (i
= 0; i
< numsigs
; i
++)
5848 signal_print
[i
] = 1;
5849 signal_program
[i
] = 1;
5852 /* Signals caused by debugger's own actions
5853 should not be given to the program afterwards. */
5854 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
5855 signal_program
[TARGET_SIGNAL_INT
] = 0;
5857 /* Signals that are not errors should not normally enter the debugger. */
5858 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
5859 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
5860 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
5861 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
5862 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
5863 signal_print
[TARGET_SIGNAL_PROF
] = 0;
5864 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
5865 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
5866 signal_stop
[TARGET_SIGNAL_IO
] = 0;
5867 signal_print
[TARGET_SIGNAL_IO
] = 0;
5868 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
5869 signal_print
[TARGET_SIGNAL_POLL
] = 0;
5870 signal_stop
[TARGET_SIGNAL_URG
] = 0;
5871 signal_print
[TARGET_SIGNAL_URG
] = 0;
5872 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
5873 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
5875 /* These signals are used internally by user-level thread
5876 implementations. (See signal(5) on Solaris.) Like the above
5877 signals, a healthy program receives and handles them as part of
5878 its normal operation. */
5879 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
5880 signal_print
[TARGET_SIGNAL_LWP
] = 0;
5881 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
5882 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
5883 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
5884 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
5886 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
5887 &stop_on_solib_events
, _("\
5888 Set stopping for shared library events."), _("\
5889 Show stopping for shared library events."), _("\
5890 If nonzero, gdb will give control to the user when the dynamic linker\n\
5891 notifies gdb of shared library events. The most common event of interest\n\
5892 to the user would be loading/unloading of a new library."),
5894 show_stop_on_solib_events
,
5895 &setlist
, &showlist
);
5897 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
5898 follow_fork_mode_kind_names
,
5899 &follow_fork_mode_string
, _("\
5900 Set debugger response to a program call of fork or vfork."), _("\
5901 Show debugger response to a program call of fork or vfork."), _("\
5902 A fork or vfork creates a new process. follow-fork-mode can be:\n\
5903 parent - the original process is debugged after a fork\n\
5904 child - the new process is debugged after a fork\n\
5905 The unfollowed process will continue to run.\n\
5906 By default, the debugger will follow the parent process."),
5908 show_follow_fork_mode_string
,
5909 &setlist
, &showlist
);
5911 add_setshow_enum_cmd ("scheduler-locking", class_run
,
5912 scheduler_enums
, &scheduler_mode
, _("\
5913 Set mode for locking scheduler during execution."), _("\
5914 Show mode for locking scheduler during execution."), _("\
5915 off == no locking (threads may preempt at any time)\n\
5916 on == full locking (no thread except the current thread may run)\n\
5917 step == scheduler locked during every single-step operation.\n\
5918 In this mode, no other thread may run during a step command.\n\
5919 Other threads may run while stepping over a function call ('next')."),
5920 set_schedlock_func
, /* traps on target vector */
5921 show_scheduler_mode
,
5922 &setlist
, &showlist
);
5924 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
5925 Set mode for resuming threads of all processes."), _("\
5926 Show mode for resuming threads of all processes."), _("\
5927 When on, execution commands (such as 'continue' or 'next') resume all\n\
5928 threads of all processes. When off (which is the default), execution\n\
5929 commands only resume the threads of the current process. The set of\n\
5930 threads that are resumed is further refined by the scheduler-locking\n\
5931 mode (see help set scheduler-locking)."),
5933 show_schedule_multiple
,
5934 &setlist
, &showlist
);
5936 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
5937 Set mode of the step operation."), _("\
5938 Show mode of the step operation."), _("\
5939 When set, doing a step over a function without debug line information\n\
5940 will stop at the first instruction of that function. Otherwise, the\n\
5941 function is skipped and the step command stops at a different source line."),
5943 show_step_stop_if_no_debug
,
5944 &setlist
, &showlist
);
5946 add_setshow_enum_cmd ("displaced-stepping", class_run
,
5947 can_use_displaced_stepping_enum
,
5948 &can_use_displaced_stepping
, _("\
5949 Set debugger's willingness to use displaced stepping."), _("\
5950 Show debugger's willingness to use displaced stepping."), _("\
5951 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
5952 supported by the target architecture. If off, gdb will not use displaced\n\
5953 stepping to step over breakpoints, even if such is supported by the target\n\
5954 architecture. If auto (which is the default), gdb will use displaced stepping\n\
5955 if the target architecture supports it and non-stop mode is active, but will not\n\
5956 use it in all-stop mode (see help set non-stop)."),
5958 show_can_use_displaced_stepping
,
5959 &setlist
, &showlist
);
5961 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
5962 &exec_direction
, _("Set direction of execution.\n\
5963 Options are 'forward' or 'reverse'."),
5964 _("Show direction of execution (forward/reverse)."),
5965 _("Tells gdb whether to execute forward or backward."),
5966 set_exec_direction_func
, show_exec_direction_func
,
5967 &setlist
, &showlist
);
5969 /* ptid initializations */
5970 null_ptid
= ptid_build (0, 0, 0);
5971 minus_one_ptid
= ptid_build (-1, 0, 0);
5972 inferior_ptid
= null_ptid
;
5973 target_last_wait_ptid
= minus_one_ptid
;
5974 displaced_step_ptid
= null_ptid
;
5976 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
5977 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
5978 observer_attach_thread_exit (infrun_thread_thread_exit
);
5980 /* Explicitly create without lookup, since that tries to create a
5981 value with a void typed value, and when we get here, gdbarch
5982 isn't initialized yet. At this point, we're quite sure there
5983 isn't another convenience variable of the same name. */
5984 create_internalvar_type_lazy ("_siginfo", siginfo_make_value
);