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 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"
49 #include "gdb_assert.h"
50 #include "mi/mi-common.h"
51 #include "event-top.h"
53 /* Prototypes for local functions */
55 static void signals_info (char *, int);
57 static void handle_command (char *, int);
59 static void sig_print_info (enum target_signal
);
61 static void sig_print_header (void);
63 static void resume_cleanups (void *);
65 static int hook_stop_stub (void *);
67 static int restore_selected_frame (void *);
69 static void build_infrun (void);
71 static int follow_fork (void);
73 static void set_schedlock_func (char *args
, int from_tty
,
74 struct cmd_list_element
*c
);
76 struct thread_stepping_state
;
78 static int currently_stepping (struct thread_stepping_state
*tss
);
80 static void xdb_handle_command (char *args
, int from_tty
);
82 static int prepare_to_proceed (int);
84 void _initialize_infrun (void);
86 /* When set, stop the 'step' command if we enter a function which has
87 no line number information. The normal behavior is that we step
88 over such function. */
89 int step_stop_if_no_debug
= 0;
91 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
92 struct cmd_list_element
*c
, const char *value
)
94 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
97 /* In asynchronous mode, but simulating synchronous execution. */
99 int sync_execution
= 0;
101 /* wait_for_inferior and normal_stop use this to notify the user
102 when the inferior stopped in a different thread than it had been
105 static ptid_t previous_inferior_ptid
;
107 int debug_displaced
= 0;
109 show_debug_displaced (struct ui_file
*file
, int from_tty
,
110 struct cmd_list_element
*c
, const char *value
)
112 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
115 static int debug_infrun
= 0;
117 show_debug_infrun (struct ui_file
*file
, int from_tty
,
118 struct cmd_list_element
*c
, const char *value
)
120 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
123 /* If the program uses ELF-style shared libraries, then calls to
124 functions in shared libraries go through stubs, which live in a
125 table called the PLT (Procedure Linkage Table). The first time the
126 function is called, the stub sends control to the dynamic linker,
127 which looks up the function's real address, patches the stub so
128 that future calls will go directly to the function, and then passes
129 control to the function.
131 If we are stepping at the source level, we don't want to see any of
132 this --- we just want to skip over the stub and the dynamic linker.
133 The simple approach is to single-step until control leaves the
136 However, on some systems (e.g., Red Hat's 5.2 distribution) the
137 dynamic linker calls functions in the shared C library, so you
138 can't tell from the PC alone whether the dynamic linker is still
139 running. In this case, we use a step-resume breakpoint to get us
140 past the dynamic linker, as if we were using "next" to step over a
143 in_solib_dynsym_resolve_code() says whether we're in the dynamic
144 linker code or not. Normally, this means we single-step. However,
145 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
146 address where we can place a step-resume breakpoint to get past the
147 linker's symbol resolution function.
149 in_solib_dynsym_resolve_code() can generally be implemented in a
150 pretty portable way, by comparing the PC against the address ranges
151 of the dynamic linker's sections.
153 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
154 it depends on internal details of the dynamic linker. It's usually
155 not too hard to figure out where to put a breakpoint, but it
156 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
157 sanity checking. If it can't figure things out, returning zero and
158 getting the (possibly confusing) stepping behavior is better than
159 signalling an error, which will obscure the change in the
162 /* This function returns TRUE if pc is the address of an instruction
163 that lies within the dynamic linker (such as the event hook, or the
166 This function must be used only when a dynamic linker event has
167 been caught, and the inferior is being stepped out of the hook, or
168 undefined results are guaranteed. */
170 #ifndef SOLIB_IN_DYNAMIC_LINKER
171 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
175 /* Convert the #defines into values. This is temporary until wfi control
176 flow is completely sorted out. */
178 #ifndef CANNOT_STEP_HW_WATCHPOINTS
179 #define CANNOT_STEP_HW_WATCHPOINTS 0
181 #undef CANNOT_STEP_HW_WATCHPOINTS
182 #define CANNOT_STEP_HW_WATCHPOINTS 1
185 /* Tables of how to react to signals; the user sets them. */
187 static unsigned char *signal_stop
;
188 static unsigned char *signal_print
;
189 static unsigned char *signal_program
;
191 #define SET_SIGS(nsigs,sigs,flags) \
193 int signum = (nsigs); \
194 while (signum-- > 0) \
195 if ((sigs)[signum]) \
196 (flags)[signum] = 1; \
199 #define UNSET_SIGS(nsigs,sigs,flags) \
201 int signum = (nsigs); \
202 while (signum-- > 0) \
203 if ((sigs)[signum]) \
204 (flags)[signum] = 0; \
207 /* Value to pass to target_resume() to cause all threads to resume */
209 #define RESUME_ALL (pid_to_ptid (-1))
211 /* Command list pointer for the "stop" placeholder. */
213 static struct cmd_list_element
*stop_command
;
215 /* Function inferior was in as of last step command. */
217 static struct symbol
*step_start_function
;
219 /* Nonzero if we are presently stepping over a breakpoint.
221 If we hit a breakpoint or watchpoint, and then continue,
222 we need to single step the current thread with breakpoints
223 disabled, to avoid hitting the same breakpoint or
224 watchpoint again. And we should step just a single
225 thread and keep other threads stopped, so that
226 other threads don't miss breakpoints while they are removed.
228 So, this variable simultaneously means that we need to single
229 step the current thread, keep other threads stopped, and that
230 breakpoints should be removed while we step.
232 This variable is set either:
233 - in proceed, when we resume inferior on user's explicit request
234 - in keep_going, if handle_inferior_event decides we need to
235 step over breakpoint.
237 The variable is cleared in clear_proceed_status, called every
238 time before we call proceed. The proceed calls wait_for_inferior,
239 which calls handle_inferior_event in a loop, and until
240 wait_for_inferior exits, this variable is changed only by keep_going. */
242 static int stepping_over_breakpoint
;
244 /* Nonzero if we want to give control to the user when we're notified
245 of shared library events by the dynamic linker. */
246 static int stop_on_solib_events
;
248 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
249 struct cmd_list_element
*c
, const char *value
)
251 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
255 /* Nonzero means expecting a trace trap
256 and should stop the inferior and return silently when it happens. */
260 /* Nonzero means expecting a trap and caller will handle it themselves.
261 It is used after attach, due to attaching to a process;
262 when running in the shell before the child program has been exec'd;
263 and when running some kinds of remote stuff (FIXME?). */
265 enum stop_kind stop_soon
;
267 /* Nonzero if proceed is being used for a "finish" command or a similar
268 situation when stop_registers should be saved. */
270 int proceed_to_finish
;
272 /* Save register contents here when about to pop a stack dummy frame,
273 if-and-only-if proceed_to_finish is set.
274 Thus this contains the return value from the called function (assuming
275 values are returned in a register). */
277 struct regcache
*stop_registers
;
279 /* Nonzero after stop if current stack frame should be printed. */
281 static int stop_print_frame
;
283 /* Step-resume or longjmp-resume breakpoint. */
284 static struct breakpoint
*step_resume_breakpoint
= NULL
;
286 /* This is a cached copy of the pid/waitstatus of the last event
287 returned by target_wait()/deprecated_target_wait_hook(). This
288 information is returned by get_last_target_status(). */
289 static ptid_t target_last_wait_ptid
;
290 static struct target_waitstatus target_last_waitstatus
;
292 /* Context-switchable data. */
293 struct thread_stepping_state
295 /* Should we step over breakpoint next time keep_going
297 int stepping_over_breakpoint
;
299 struct symtab
*current_symtab
;
300 int step_after_step_resume_breakpoint
;
301 int stepping_through_solib_after_catch
;
302 bpstat stepping_through_solib_catchpoints
;
305 struct thread_stepping_state gtss
;
306 struct thread_stepping_state
*tss
= >ss
;
308 static void context_switch (ptid_t ptid
);
310 void init_thread_stepping_state (struct thread_stepping_state
*tss
);
312 void init_infwait_state (void);
314 /* This is used to remember when a fork, vfork or exec event
315 was caught by a catchpoint, and thus the event is to be
316 followed at the next resume of the inferior, and not
320 enum target_waitkind kind
;
327 char *execd_pathname
;
331 static const char follow_fork_mode_child
[] = "child";
332 static const char follow_fork_mode_parent
[] = "parent";
334 static const char *follow_fork_mode_kind_names
[] = {
335 follow_fork_mode_child
,
336 follow_fork_mode_parent
,
340 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
342 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
343 struct cmd_list_element
*c
, const char *value
)
345 fprintf_filtered (file
, _("\
346 Debugger response to a program call of fork or vfork is \"%s\".\n"),
354 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
356 return target_follow_fork (follow_child
);
360 follow_inferior_reset_breakpoints (void)
362 /* Was there a step_resume breakpoint? (There was if the user
363 did a "next" at the fork() call.) If so, explicitly reset its
366 step_resumes are a form of bp that are made to be per-thread.
367 Since we created the step_resume bp when the parent process
368 was being debugged, and now are switching to the child process,
369 from the breakpoint package's viewpoint, that's a switch of
370 "threads". We must update the bp's notion of which thread
371 it is for, or it'll be ignored when it triggers. */
373 if (step_resume_breakpoint
)
374 breakpoint_re_set_thread (step_resume_breakpoint
);
376 /* Reinsert all breakpoints in the child. The user may have set
377 breakpoints after catching the fork, in which case those
378 were never set in the child, but only in the parent. This makes
379 sure the inserted breakpoints match the breakpoint list. */
381 breakpoint_re_set ();
382 insert_breakpoints ();
385 /* EXECD_PATHNAME is assumed to be non-NULL. */
388 follow_exec (ptid_t pid
, char *execd_pathname
)
390 ptid_t saved_pid
= pid
;
391 struct target_ops
*tgt
;
393 /* This is an exec event that we actually wish to pay attention to.
394 Refresh our symbol table to the newly exec'd program, remove any
397 If there are breakpoints, they aren't really inserted now,
398 since the exec() transformed our inferior into a fresh set
401 We want to preserve symbolic breakpoints on the list, since
402 we have hopes that they can be reset after the new a.out's
403 symbol table is read.
405 However, any "raw" breakpoints must be removed from the list
406 (e.g., the solib bp's), since their address is probably invalid
409 And, we DON'T want to call delete_breakpoints() here, since
410 that may write the bp's "shadow contents" (the instruction
411 value that was overwritten witha TRAP instruction). Since
412 we now have a new a.out, those shadow contents aren't valid. */
413 update_breakpoints_after_exec ();
415 /* If there was one, it's gone now. We cannot truly step-to-next
416 statement through an exec(). */
417 step_resume_breakpoint
= NULL
;
418 step_range_start
= 0;
421 /* What is this a.out's name? */
422 printf_unfiltered (_("Executing new program: %s\n"), execd_pathname
);
424 /* We've followed the inferior through an exec. Therefore, the
425 inferior has essentially been killed & reborn. */
427 gdb_flush (gdb_stdout
);
428 generic_mourn_inferior ();
429 /* Because mourn_inferior resets inferior_ptid. */
430 inferior_ptid
= saved_pid
;
432 if (gdb_sysroot
&& *gdb_sysroot
)
434 char *name
= alloca (strlen (gdb_sysroot
)
435 + strlen (execd_pathname
)
437 strcpy (name
, gdb_sysroot
);
438 strcat (name
, execd_pathname
);
439 execd_pathname
= name
;
442 /* That a.out is now the one to use. */
443 exec_file_attach (execd_pathname
, 0);
445 /* Reset the shared library package. This ensures that we get a
446 shlib event when the child reaches "_start", at which point the
447 dld will have had a chance to initialize the child. */
448 /* Also, loading a symbol file below may trigger symbol lookups, and
449 we don't want those to be satisfied by the libraries of the
450 previous incarnation of this process. */
451 no_shared_libraries (NULL
, 0);
453 /* Load the main file's symbols. */
454 symbol_file_add_main (execd_pathname
, 0);
456 #ifdef SOLIB_CREATE_INFERIOR_HOOK
457 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
459 solib_create_inferior_hook ();
462 /* Reinsert all breakpoints. (Those which were symbolic have
463 been reset to the proper address in the new a.out, thanks
464 to symbol_file_command...) */
465 insert_breakpoints ();
467 /* The next resume of this inferior should bring it to the shlib
468 startup breakpoints. (If the user had also set bp's on
469 "main" from the old (parent) process, then they'll auto-
470 matically get reset there in the new process.) */
473 /* Non-zero if we just simulating a single-step. This is needed
474 because we cannot remove the breakpoints in the inferior process
475 until after the `wait' in `wait_for_inferior'. */
476 static int singlestep_breakpoints_inserted_p
= 0;
478 /* The thread we inserted single-step breakpoints for. */
479 static ptid_t singlestep_ptid
;
481 /* PC when we started this single-step. */
482 static CORE_ADDR singlestep_pc
;
484 /* If another thread hit the singlestep breakpoint, we save the original
485 thread here so that we can resume single-stepping it later. */
486 static ptid_t saved_singlestep_ptid
;
487 static int stepping_past_singlestep_breakpoint
;
489 /* If not equal to null_ptid, this means that after stepping over breakpoint
490 is finished, we need to switch to deferred_step_ptid, and step it.
492 The use case is when one thread has hit a breakpoint, and then the user
493 has switched to another thread and issued 'step'. We need to step over
494 breakpoint in the thread which hit the breakpoint, but then continue
495 stepping the thread user has selected. */
496 static ptid_t deferred_step_ptid
;
498 /* Displaced stepping. */
500 /* In non-stop debugging mode, we must take special care to manage
501 breakpoints properly; in particular, the traditional strategy for
502 stepping a thread past a breakpoint it has hit is unsuitable.
503 'Displaced stepping' is a tactic for stepping one thread past a
504 breakpoint it has hit while ensuring that other threads running
505 concurrently will hit the breakpoint as they should.
507 The traditional way to step a thread T off a breakpoint in a
508 multi-threaded program in all-stop mode is as follows:
510 a0) Initially, all threads are stopped, and breakpoints are not
512 a1) We single-step T, leaving breakpoints uninserted.
513 a2) We insert breakpoints, and resume all threads.
515 In non-stop debugging, however, this strategy is unsuitable: we
516 don't want to have to stop all threads in the system in order to
517 continue or step T past a breakpoint. Instead, we use displaced
520 n0) Initially, T is stopped, other threads are running, and
521 breakpoints are inserted.
522 n1) We copy the instruction "under" the breakpoint to a separate
523 location, outside the main code stream, making any adjustments
524 to the instruction, register, and memory state as directed by
526 n2) We single-step T over the instruction at its new location.
527 n3) We adjust the resulting register and memory state as directed
528 by T's architecture. This includes resetting T's PC to point
529 back into the main instruction stream.
532 This approach depends on the following gdbarch methods:
534 - gdbarch_max_insn_length and gdbarch_displaced_step_location
535 indicate where to copy the instruction, and how much space must
536 be reserved there. We use these in step n1.
538 - gdbarch_displaced_step_copy_insn copies a instruction to a new
539 address, and makes any necessary adjustments to the instruction,
540 register contents, and memory. We use this in step n1.
542 - gdbarch_displaced_step_fixup adjusts registers and memory after
543 we have successfuly single-stepped the instruction, to yield the
544 same effect the instruction would have had if we had executed it
545 at its original address. We use this in step n3.
547 - gdbarch_displaced_step_free_closure provides cleanup.
549 The gdbarch_displaced_step_copy_insn and
550 gdbarch_displaced_step_fixup functions must be written so that
551 copying an instruction with gdbarch_displaced_step_copy_insn,
552 single-stepping across the copied instruction, and then applying
553 gdbarch_displaced_insn_fixup should have the same effects on the
554 thread's memory and registers as stepping the instruction in place
555 would have. Exactly which responsibilities fall to the copy and
556 which fall to the fixup is up to the author of those functions.
558 See the comments in gdbarch.sh for details.
560 Note that displaced stepping and software single-step cannot
561 currently be used in combination, although with some care I think
562 they could be made to. Software single-step works by placing
563 breakpoints on all possible subsequent instructions; if the
564 displaced instruction is a PC-relative jump, those breakpoints
565 could fall in very strange places --- on pages that aren't
566 executable, or at addresses that are not proper instruction
567 boundaries. (We do generally let other threads run while we wait
568 to hit the software single-step breakpoint, and they might
569 encounter such a corrupted instruction.) One way to work around
570 this would be to have gdbarch_displaced_step_copy_insn fully
571 simulate the effect of PC-relative instructions (and return NULL)
572 on architectures that use software single-stepping.
574 In non-stop mode, we can have independent and simultaneous step
575 requests, so more than one thread may need to simultaneously step
576 over a breakpoint. The current implementation assumes there is
577 only one scratch space per process. In this case, we have to
578 serialize access to the scratch space. If thread A wants to step
579 over a breakpoint, but we are currently waiting for some other
580 thread to complete a displaced step, we leave thread A stopped and
581 place it in the displaced_step_request_queue. Whenever a displaced
582 step finishes, we pick the next thread in the queue and start a new
583 displaced step operation on it. See displaced_step_prepare and
584 displaced_step_fixup for details. */
586 /* If this is not null_ptid, this is the thread carrying out a
587 displaced single-step. This thread's state will require fixing up
588 once it has completed its step. */
589 static ptid_t displaced_step_ptid
;
591 struct displaced_step_request
594 struct displaced_step_request
*next
;
597 /* A queue of pending displaced stepping requests. */
598 struct displaced_step_request
*displaced_step_request_queue
;
600 /* The architecture the thread had when we stepped it. */
601 static struct gdbarch
*displaced_step_gdbarch
;
603 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
604 for post-step cleanup. */
605 static struct displaced_step_closure
*displaced_step_closure
;
607 /* The address of the original instruction, and the copy we made. */
608 static CORE_ADDR displaced_step_original
, displaced_step_copy
;
610 /* Saved contents of copy area. */
611 static gdb_byte
*displaced_step_saved_copy
;
613 /* When this is non-zero, we are allowed to use displaced stepping, if
614 the architecture supports it. When this is zero, we use
615 traditional the hold-and-step approach. */
616 int can_use_displaced_stepping
= 1;
618 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
619 struct cmd_list_element
*c
,
622 fprintf_filtered (file
, _("\
623 Debugger's willingness to use displaced stepping to step over "
624 "breakpoints is %s.\n"), value
);
627 /* Return non-zero if displaced stepping is enabled, and can be used
630 use_displaced_stepping (struct gdbarch
*gdbarch
)
632 return (can_use_displaced_stepping
633 && gdbarch_displaced_step_copy_insn_p (gdbarch
));
636 /* Clean out any stray displaced stepping state. */
638 displaced_step_clear (void)
640 /* Indicate that there is no cleanup pending. */
641 displaced_step_ptid
= null_ptid
;
643 if (displaced_step_closure
)
645 gdbarch_displaced_step_free_closure (displaced_step_gdbarch
,
646 displaced_step_closure
);
647 displaced_step_closure
= NULL
;
652 cleanup_displaced_step_closure (void *ptr
)
654 struct displaced_step_closure
*closure
= ptr
;
656 gdbarch_displaced_step_free_closure (current_gdbarch
, closure
);
659 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
661 displaced_step_dump_bytes (struct ui_file
*file
,
667 for (i
= 0; i
< len
; i
++)
668 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
669 fputs_unfiltered ("\n", file
);
672 /* Prepare to single-step, using displaced stepping.
674 Note that we cannot use displaced stepping when we have a signal to
675 deliver. If we have a signal to deliver and an instruction to step
676 over, then after the step, there will be no indication from the
677 target whether the thread entered a signal handler or ignored the
678 signal and stepped over the instruction successfully --- both cases
679 result in a simple SIGTRAP. In the first case we mustn't do a
680 fixup, and in the second case we must --- but we can't tell which.
681 Comments in the code for 'random signals' in handle_inferior_event
682 explain how we handle this case instead.
684 Returns 1 if preparing was successful -- this thread is going to be
685 stepped now; or 0 if displaced stepping this thread got queued. */
687 displaced_step_prepare (ptid_t ptid
)
689 struct cleanup
*old_cleanups
;
690 struct regcache
*regcache
= get_thread_regcache (ptid
);
691 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
692 CORE_ADDR original
, copy
;
694 struct displaced_step_closure
*closure
;
696 /* We should never reach this function if the architecture does not
697 support displaced stepping. */
698 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
700 /* For the first cut, we're displaced stepping one thread at a
703 if (!ptid_equal (displaced_step_ptid
, null_ptid
))
705 /* Already waiting for a displaced step to finish. Defer this
706 request and place in queue. */
707 struct displaced_step_request
*req
, *new_req
;
710 fprintf_unfiltered (gdb_stdlog
,
711 "displaced: defering step of %s\n",
712 target_pid_to_str (ptid
));
714 new_req
= xmalloc (sizeof (*new_req
));
715 new_req
->ptid
= ptid
;
716 new_req
->next
= NULL
;
718 if (displaced_step_request_queue
)
720 for (req
= displaced_step_request_queue
;
727 displaced_step_request_queue
= new_req
;
734 fprintf_unfiltered (gdb_stdlog
,
735 "displaced: stepping %s now\n",
736 target_pid_to_str (ptid
));
739 displaced_step_clear ();
741 original
= regcache_read_pc (regcache
);
743 copy
= gdbarch_displaced_step_location (gdbarch
);
744 len
= gdbarch_max_insn_length (gdbarch
);
746 /* Save the original contents of the copy area. */
747 displaced_step_saved_copy
= xmalloc (len
);
748 old_cleanups
= make_cleanup (free_current_contents
,
749 &displaced_step_saved_copy
);
750 read_memory (copy
, displaced_step_saved_copy
, len
);
753 fprintf_unfiltered (gdb_stdlog
, "displaced: saved 0x%s: ",
755 displaced_step_dump_bytes (gdb_stdlog
, displaced_step_saved_copy
, len
);
758 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
759 original
, copy
, regcache
);
761 /* We don't support the fully-simulated case at present. */
762 gdb_assert (closure
);
764 make_cleanup (cleanup_displaced_step_closure
, closure
);
766 /* Resume execution at the copy. */
767 regcache_write_pc (regcache
, copy
);
769 discard_cleanups (old_cleanups
);
772 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to 0x%s\n",
775 /* Save the information we need to fix things up if the step
777 displaced_step_ptid
= ptid
;
778 displaced_step_gdbarch
= gdbarch
;
779 displaced_step_closure
= closure
;
780 displaced_step_original
= original
;
781 displaced_step_copy
= copy
;
786 displaced_step_clear_cleanup (void *ignore
)
788 displaced_step_clear ();
792 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
, const gdb_byte
*myaddr
, int len
)
794 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
795 inferior_ptid
= ptid
;
796 write_memory (memaddr
, myaddr
, len
);
797 do_cleanups (ptid_cleanup
);
801 displaced_step_fixup (ptid_t event_ptid
, enum target_signal signal
)
803 struct cleanup
*old_cleanups
;
805 /* Was this event for the pid we displaced? */
806 if (ptid_equal (displaced_step_ptid
, null_ptid
)
807 || ! ptid_equal (displaced_step_ptid
, event_ptid
))
810 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, 0);
812 /* Restore the contents of the copy area. */
814 ULONGEST len
= gdbarch_max_insn_length (displaced_step_gdbarch
);
815 write_memory_ptid (displaced_step_ptid
, displaced_step_copy
,
816 displaced_step_saved_copy
, len
);
818 fprintf_unfiltered (gdb_stdlog
, "displaced: restored 0x%s\n",
819 paddr_nz (displaced_step_copy
));
822 /* Did the instruction complete successfully? */
823 if (signal
== TARGET_SIGNAL_TRAP
)
825 /* Fix up the resulting state. */
826 gdbarch_displaced_step_fixup (displaced_step_gdbarch
,
827 displaced_step_closure
,
828 displaced_step_original
,
830 get_thread_regcache (displaced_step_ptid
));
834 /* Since the instruction didn't complete, all we can do is
836 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
837 CORE_ADDR pc
= regcache_read_pc (regcache
);
838 pc
= displaced_step_original
+ (pc
- displaced_step_copy
);
839 regcache_write_pc (regcache
, pc
);
842 do_cleanups (old_cleanups
);
844 /* Are there any pending displaced stepping requests? If so, run
846 if (displaced_step_request_queue
)
848 struct displaced_step_request
*head
;
851 head
= displaced_step_request_queue
;
853 displaced_step_request_queue
= head
->next
;
857 fprintf_unfiltered (gdb_stdlog
,
858 "displaced: stepping queued %s now\n",
859 target_pid_to_str (ptid
));
862 displaced_step_ptid
= null_ptid
;
863 displaced_step_prepare (ptid
);
864 target_resume (ptid
, 1, TARGET_SIGNAL_0
);
871 /* Things to clean up if we QUIT out of resume (). */
873 resume_cleanups (void *ignore
)
878 static const char schedlock_off
[] = "off";
879 static const char schedlock_on
[] = "on";
880 static const char schedlock_step
[] = "step";
881 static const char *scheduler_enums
[] = {
887 static const char *scheduler_mode
= schedlock_off
;
889 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
890 struct cmd_list_element
*c
, const char *value
)
892 fprintf_filtered (file
, _("\
893 Mode for locking scheduler during execution is \"%s\".\n"),
898 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
900 if (!target_can_lock_scheduler
)
902 scheduler_mode
= schedlock_off
;
903 error (_("Target '%s' cannot support this command."), target_shortname
);
908 /* Resume the inferior, but allow a QUIT. This is useful if the user
909 wants to interrupt some lengthy single-stepping operation
910 (for child processes, the SIGINT goes to the inferior, and so
911 we get a SIGINT random_signal, but for remote debugging and perhaps
912 other targets, that's not true).
914 STEP nonzero if we should step (zero to continue instead).
915 SIG is the signal to give the inferior (zero for none). */
917 resume (int step
, enum target_signal sig
)
919 int should_resume
= 1;
920 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
921 struct regcache
*regcache
= get_current_regcache ();
922 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
923 CORE_ADDR pc
= regcache_read_pc (regcache
);
927 fprintf_unfiltered (gdb_stdlog
,
928 "infrun: resume (step=%d, signal=%d), "
929 "stepping_over_breakpoint=%d\n",
930 step
, sig
, stepping_over_breakpoint
);
932 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
933 over an instruction that causes a page fault without triggering
934 a hardware watchpoint. The kernel properly notices that it shouldn't
935 stop, because the hardware watchpoint is not triggered, but it forgets
936 the step request and continues the program normally.
937 Work around the problem by removing hardware watchpoints if a step is
938 requested, GDB will check for a hardware watchpoint trigger after the
940 if (CANNOT_STEP_HW_WATCHPOINTS
&& step
)
941 remove_hw_watchpoints ();
944 /* Normally, by the time we reach `resume', the breakpoints are either
945 removed or inserted, as appropriate. The exception is if we're sitting
946 at a permanent breakpoint; we need to step over it, but permanent
947 breakpoints can't be removed. So we have to test for it here. */
948 if (breakpoint_here_p (pc
) == permanent_breakpoint_here
)
950 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
951 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
954 The program is stopped at a permanent breakpoint, but GDB does not know\n\
955 how to step past a permanent breakpoint on this architecture. Try using\n\
956 a command like `return' or `jump' to continue execution."));
959 /* If enabled, step over breakpoints by executing a copy of the
960 instruction at a different address.
962 We can't use displaced stepping when we have a signal to deliver;
963 the comments for displaced_step_prepare explain why. The
964 comments in the handle_inferior event for dealing with 'random
965 signals' explain what we do instead. */
966 if (use_displaced_stepping (gdbarch
)
967 && stepping_over_breakpoint
968 && sig
== TARGET_SIGNAL_0
)
970 if (!displaced_step_prepare (inferior_ptid
))
972 /* Got placed in displaced stepping queue. Will be resumed
973 later when all the currently queued displaced stepping
975 discard_cleanups (old_cleanups
);
980 if (step
&& gdbarch_software_single_step_p (gdbarch
))
982 /* Do it the hard way, w/temp breakpoints */
983 if (gdbarch_software_single_step (gdbarch
, get_current_frame ()))
985 /* ...and don't ask hardware to do it. */
987 /* and do not pull these breakpoints until after a `wait' in
988 `wait_for_inferior' */
989 singlestep_breakpoints_inserted_p
= 1;
990 singlestep_ptid
= inferior_ptid
;
995 /* If there were any forks/vforks/execs that were caught and are
996 now to be followed, then do so. */
997 switch (pending_follow
.kind
)
999 case TARGET_WAITKIND_FORKED
:
1000 case TARGET_WAITKIND_VFORKED
:
1001 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
1006 case TARGET_WAITKIND_EXECD
:
1007 /* follow_exec is called as soon as the exec event is seen. */
1008 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
1015 /* Install inferior's terminal modes. */
1016 target_terminal_inferior ();
1022 resume_ptid
= RESUME_ALL
; /* Default */
1024 /* If STEP is set, it's a request to use hardware stepping
1025 facilities. But in that case, we should never
1026 use singlestep breakpoint. */
1027 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1029 if (singlestep_breakpoints_inserted_p
1030 && stepping_past_singlestep_breakpoint
)
1032 /* The situation here is as follows. In thread T1 we wanted to
1033 single-step. Lacking hardware single-stepping we've
1034 set breakpoint at the PC of the next instruction -- call it
1035 P. After resuming, we've hit that breakpoint in thread T2.
1036 Now we've removed original breakpoint, inserted breakpoint
1037 at P+1, and try to step to advance T2 past breakpoint.
1038 We need to step only T2, as if T1 is allowed to freely run,
1039 it can run past P, and if other threads are allowed to run,
1040 they can hit breakpoint at P+1, and nested hits of single-step
1041 breakpoints is not something we'd want -- that's complicated
1042 to support, and has no value. */
1043 resume_ptid
= inferior_ptid
;
1046 if ((step
|| singlestep_breakpoints_inserted_p
)
1047 && stepping_over_breakpoint
)
1049 /* We're allowing a thread to run past a breakpoint it has
1050 hit, by single-stepping the thread with the breakpoint
1051 removed. In which case, we need to single-step only this
1052 thread, and keep others stopped, as they can miss this
1053 breakpoint if allowed to run.
1055 The current code actually removes all breakpoints when
1056 doing this, not just the one being stepped over, so if we
1057 let other threads run, we can actually miss any
1058 breakpoint, not just the one at PC. */
1059 resume_ptid
= inferior_ptid
;
1064 /* With non-stop mode on, threads are always handled
1066 resume_ptid
= inferior_ptid
;
1068 else if ((scheduler_mode
== schedlock_on
)
1069 || (scheduler_mode
== schedlock_step
1070 && (step
|| singlestep_breakpoints_inserted_p
)))
1072 /* User-settable 'scheduler' mode requires solo thread resume. */
1073 resume_ptid
= inferior_ptid
;
1076 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1078 /* Most targets can step a breakpoint instruction, thus
1079 executing it normally. But if this one cannot, just
1080 continue and we will hit it anyway. */
1081 if (step
&& breakpoint_inserted_here_p (pc
))
1086 && use_displaced_stepping (gdbarch
)
1087 && stepping_over_breakpoint
)
1089 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1090 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1093 fprintf_unfiltered (gdb_stdlog
, "displaced: run 0x%s: ",
1094 paddr_nz (actual_pc
));
1095 read_memory (actual_pc
, buf
, sizeof (buf
));
1096 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1099 target_resume (resume_ptid
, step
, sig
);
1102 discard_cleanups (old_cleanups
);
1107 /* Clear out all variables saying what to do when inferior is continued.
1108 First do this, then set the ones you want, then call `proceed'. */
1111 clear_proceed_status (void)
1113 stepping_over_breakpoint
= 0;
1114 step_range_start
= 0;
1116 step_frame_id
= null_frame_id
;
1117 step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1118 stop_after_trap
= 0;
1119 stop_soon
= NO_STOP_QUIETLY
;
1120 proceed_to_finish
= 0;
1121 breakpoint_proceeded
= 1; /* We're about to proceed... */
1125 regcache_xfree (stop_registers
);
1126 stop_registers
= NULL
;
1129 /* Discard any remaining commands or status from previous stop. */
1130 bpstat_clear (&stop_bpstat
);
1133 /* This should be suitable for any targets that support threads. */
1136 prepare_to_proceed (int step
)
1139 struct target_waitstatus wait_status
;
1141 /* Get the last target status returned by target_wait(). */
1142 get_last_target_status (&wait_ptid
, &wait_status
);
1144 /* Make sure we were stopped at a breakpoint. */
1145 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
1146 || wait_status
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1151 /* Switched over from WAIT_PID. */
1152 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
1153 && !ptid_equal (inferior_ptid
, wait_ptid
))
1155 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
1157 if (breakpoint_here_p (regcache_read_pc (regcache
)))
1159 /* If stepping, remember current thread to switch back to. */
1161 deferred_step_ptid
= inferior_ptid
;
1163 /* Switch back to WAIT_PID thread. */
1164 switch_to_thread (wait_ptid
);
1166 /* We return 1 to indicate that there is a breakpoint here,
1167 so we need to step over it before continuing to avoid
1168 hitting it straight away. */
1176 /* Record the pc of the program the last time it stopped. This is
1177 just used internally by wait_for_inferior, but need to be preserved
1178 over calls to it and cleared when the inferior is started. */
1179 static CORE_ADDR prev_pc
;
1181 /* Basic routine for continuing the program in various fashions.
1183 ADDR is the address to resume at, or -1 for resume where stopped.
1184 SIGGNAL is the signal to give it, or 0 for none,
1185 or -1 for act according to how it stopped.
1186 STEP is nonzero if should trap after one instruction.
1187 -1 means return after that and print nothing.
1188 You should probably set various step_... variables
1189 before calling here, if you are stepping.
1191 You should call clear_proceed_status before calling proceed. */
1194 proceed (CORE_ADDR addr
, enum target_signal siggnal
, int step
)
1196 struct regcache
*regcache
= get_current_regcache ();
1197 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1198 CORE_ADDR pc
= regcache_read_pc (regcache
);
1202 step_start_function
= find_pc_function (pc
);
1204 stop_after_trap
= 1;
1206 if (addr
== (CORE_ADDR
) -1)
1208 if (pc
== stop_pc
&& breakpoint_here_p (pc
))
1209 /* There is a breakpoint at the address we will resume at,
1210 step one instruction before inserting breakpoints so that
1211 we do not stop right away (and report a second hit at this
1214 else if (gdbarch_single_step_through_delay_p (gdbarch
)
1215 && gdbarch_single_step_through_delay (gdbarch
,
1216 get_current_frame ()))
1217 /* We stepped onto an instruction that needs to be stepped
1218 again before re-inserting the breakpoint, do so. */
1223 regcache_write_pc (regcache
, addr
);
1227 fprintf_unfiltered (gdb_stdlog
,
1228 "infrun: proceed (addr=0x%s, signal=%d, step=%d)\n",
1229 paddr_nz (addr
), siggnal
, step
);
1232 /* In non-stop, each thread is handled individually. The context
1233 must already be set to the right thread here. */
1237 /* In a multi-threaded task we may select another thread and
1238 then continue or step.
1240 But if the old thread was stopped at a breakpoint, it will
1241 immediately cause another breakpoint stop without any
1242 execution (i.e. it will report a breakpoint hit incorrectly).
1243 So we must step over it first.
1245 prepare_to_proceed checks the current thread against the
1246 thread that reported the most recent event. If a step-over
1247 is required it returns TRUE and sets the current thread to
1249 if (prepare_to_proceed (step
))
1255 stepping_over_breakpoint
= 1;
1256 /* If displaced stepping is enabled, we can step over the
1257 breakpoint without hitting it, so leave all breakpoints
1258 inserted. Otherwise we need to disable all breakpoints, step
1259 one instruction, and then re-add them when that step is
1261 if (!use_displaced_stepping (gdbarch
))
1262 remove_breakpoints ();
1265 /* We can insert breakpoints if we're not trying to step over one,
1266 or if we are stepping over one but we're using displaced stepping
1268 if (! stepping_over_breakpoint
|| use_displaced_stepping (gdbarch
))
1269 insert_breakpoints ();
1271 if (siggnal
!= TARGET_SIGNAL_DEFAULT
)
1272 stop_signal
= siggnal
;
1273 /* If this signal should not be seen by program,
1274 give it zero. Used for debugging signals. */
1275 else if (!signal_program
[stop_signal
])
1276 stop_signal
= TARGET_SIGNAL_0
;
1278 annotate_starting ();
1280 /* Make sure that output from GDB appears before output from the
1282 gdb_flush (gdb_stdout
);
1284 /* Refresh prev_pc value just prior to resuming. This used to be
1285 done in stop_stepping, however, setting prev_pc there did not handle
1286 scenarios such as inferior function calls or returning from
1287 a function via the return command. In those cases, the prev_pc
1288 value was not set properly for subsequent commands. The prev_pc value
1289 is used to initialize the starting line number in the ecs. With an
1290 invalid value, the gdb next command ends up stopping at the position
1291 represented by the next line table entry past our start position.
1292 On platforms that generate one line table entry per line, this
1293 is not a problem. However, on the ia64, the compiler generates
1294 extraneous line table entries that do not increase the line number.
1295 When we issue the gdb next command on the ia64 after an inferior call
1296 or a return command, we often end up a few instructions forward, still
1297 within the original line we started.
1299 An attempt was made to have init_execution_control_state () refresh
1300 the prev_pc value before calculating the line number. This approach
1301 did not work because on platforms that use ptrace, the pc register
1302 cannot be read unless the inferior is stopped. At that point, we
1303 are not guaranteed the inferior is stopped and so the regcache_read_pc ()
1304 call can fail. Setting the prev_pc value here ensures the value is
1305 updated correctly when the inferior is stopped. */
1306 prev_pc
= regcache_read_pc (get_current_regcache ());
1308 /* Fill in with reasonable starting values. */
1309 init_thread_stepping_state (tss
);
1311 /* We'll update this if & when we switch to a new thread. */
1312 previous_inferior_ptid
= inferior_ptid
;
1314 /* Reset to normal state. */
1315 init_infwait_state ();
1317 /* Resume inferior. */
1318 resume (oneproc
|| step
|| bpstat_should_step (), stop_signal
);
1320 /* Wait for it to stop (if not standalone)
1321 and in any case decode why it stopped, and act accordingly. */
1322 /* Do this only if we are not using the event loop, or if the target
1323 does not support asynchronous execution. */
1324 if (!target_can_async_p ())
1326 wait_for_inferior (0);
1332 /* Start remote-debugging of a machine over a serial link. */
1335 start_remote (int from_tty
)
1337 init_wait_for_inferior ();
1338 stop_soon
= STOP_QUIETLY_REMOTE
;
1339 stepping_over_breakpoint
= 0;
1341 /* Always go on waiting for the target, regardless of the mode. */
1342 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1343 indicate to wait_for_inferior that a target should timeout if
1344 nothing is returned (instead of just blocking). Because of this,
1345 targets expecting an immediate response need to, internally, set
1346 things up so that the target_wait() is forced to eventually
1348 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1349 differentiate to its caller what the state of the target is after
1350 the initial open has been performed. Here we're assuming that
1351 the target has stopped. It should be possible to eventually have
1352 target_open() return to the caller an indication that the target
1353 is currently running and GDB state should be set to the same as
1354 for an async run. */
1355 wait_for_inferior (0);
1357 /* Now that the inferior has stopped, do any bookkeeping like
1358 loading shared libraries. We want to do this before normal_stop,
1359 so that the displayed frame is up to date. */
1360 post_create_inferior (¤t_target
, from_tty
);
1365 /* Initialize static vars when a new inferior begins. */
1368 init_wait_for_inferior (void)
1370 /* These are meaningless until the first time through wait_for_inferior. */
1373 breakpoint_init_inferior (inf_starting
);
1375 /* Don't confuse first call to proceed(). */
1376 stop_signal
= TARGET_SIGNAL_0
;
1378 /* The first resume is not following a fork/vfork/exec. */
1379 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
; /* I.e., none. */
1381 clear_proceed_status ();
1383 stepping_past_singlestep_breakpoint
= 0;
1384 deferred_step_ptid
= null_ptid
;
1386 target_last_wait_ptid
= minus_one_ptid
;
1388 init_thread_stepping_state (tss
);
1389 previous_inferior_ptid
= null_ptid
;
1390 init_infwait_state ();
1392 displaced_step_clear ();
1396 /* This enum encodes possible reasons for doing a target_wait, so that
1397 wfi can call target_wait in one place. (Ultimately the call will be
1398 moved out of the infinite loop entirely.) */
1402 infwait_normal_state
,
1403 infwait_thread_hop_state
,
1404 infwait_step_watch_state
,
1405 infwait_nonstep_watch_state
1408 /* Why did the inferior stop? Used to print the appropriate messages
1409 to the interface from within handle_inferior_event(). */
1410 enum inferior_stop_reason
1412 /* Step, next, nexti, stepi finished. */
1414 /* Inferior terminated by signal. */
1416 /* Inferior exited. */
1418 /* Inferior received signal, and user asked to be notified. */
1422 /* The PTID we'll do a target_wait on.*/
1425 /* Current inferior wait state. */
1426 enum infwait_states infwait_state
;
1428 /* Data to be passed around while handling an event. This data is
1429 discarded between events. */
1430 struct execution_control_state
1433 struct target_waitstatus ws
;
1435 CORE_ADDR stop_func_start
;
1436 CORE_ADDR stop_func_end
;
1437 char *stop_func_name
;
1438 int new_thread_event
;
1442 void init_execution_control_state (struct execution_control_state
*ecs
);
1444 void handle_inferior_event (struct execution_control_state
*ecs
);
1446 static void step_into_function (struct execution_control_state
*ecs
);
1447 static void insert_step_resume_breakpoint_at_frame (struct frame_info
*step_frame
);
1448 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
1449 static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
1450 struct frame_id sr_id
);
1451 static void insert_longjmp_resume_breakpoint (CORE_ADDR
);
1453 static void stop_stepping (struct execution_control_state
*ecs
);
1454 static void prepare_to_wait (struct execution_control_state
*ecs
);
1455 static void keep_going (struct execution_control_state
*ecs
);
1456 static void print_stop_reason (enum inferior_stop_reason stop_reason
,
1459 /* Wait for control to return from inferior to debugger.
1461 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
1462 as if they were SIGTRAP signals. This can be useful during
1463 the startup sequence on some targets such as HP/UX, where
1464 we receive an EXEC event instead of the expected SIGTRAP.
1466 If inferior gets a signal, we may decide to start it up again
1467 instead of returning. That is why there is a loop in this function.
1468 When this function actually returns it means the inferior
1469 should be left stopped and GDB should read more commands. */
1472 wait_for_inferior (int treat_exec_as_sigtrap
)
1474 struct cleanup
*old_cleanups
;
1475 struct execution_control_state ecss
;
1476 struct execution_control_state
*ecs
;
1480 (gdb_stdlog
, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
1481 treat_exec_as_sigtrap
);
1483 old_cleanups
= make_cleanup (delete_step_resume_breakpoint
,
1484 &step_resume_breakpoint
);
1487 memset (ecs
, 0, sizeof (*ecs
));
1489 overlay_cache_invalid
= 1;
1491 /* We have to invalidate the registers BEFORE calling target_wait
1492 because they can be loaded from the target while in target_wait.
1493 This makes remote debugging a bit more efficient for those
1494 targets that provide critical registers as part of their normal
1495 status mechanism. */
1497 registers_changed ();
1501 if (deprecated_target_wait_hook
)
1502 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
);
1504 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
);
1506 if (treat_exec_as_sigtrap
&& ecs
->ws
.kind
== TARGET_WAITKIND_EXECD
)
1508 xfree (ecs
->ws
.value
.execd_pathname
);
1509 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
1510 ecs
->ws
.value
.sig
= TARGET_SIGNAL_TRAP
;
1513 /* Now figure out what to do with the result of the result. */
1514 handle_inferior_event (ecs
);
1516 if (!ecs
->wait_some_more
)
1519 do_cleanups (old_cleanups
);
1522 /* Asynchronous version of wait_for_inferior. It is called by the
1523 event loop whenever a change of state is detected on the file
1524 descriptor corresponding to the target. It can be called more than
1525 once to complete a single execution command. In such cases we need
1526 to keep the state in a global variable ECSS. If it is the last time
1527 that this function is called for a single execution command, then
1528 report to the user that the inferior has stopped, and do the
1529 necessary cleanups. */
1532 fetch_inferior_event (void *client_data
)
1534 struct execution_control_state ecss
;
1535 struct execution_control_state
*ecs
= &ecss
;
1536 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
1537 int was_sync
= sync_execution
;
1539 memset (ecs
, 0, sizeof (*ecs
));
1541 overlay_cache_invalid
= 1;
1544 /* In non-stop mode, the user/frontend should not notice a thread
1545 switch due to internal events. Make sure we reverse to the
1546 user selected thread and frame after handling the event and
1547 running any breakpoint commands. */
1548 make_cleanup_restore_current_thread ();
1550 /* We have to invalidate the registers BEFORE calling target_wait
1551 because they can be loaded from the target while in target_wait.
1552 This makes remote debugging a bit more efficient for those
1553 targets that provide critical registers as part of their normal
1554 status mechanism. */
1556 registers_changed ();
1558 if (deprecated_target_wait_hook
)
1560 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
);
1562 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
);
1565 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
1566 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1567 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
1568 /* In non-stop mode, each thread is handled individually. Switch
1569 early, so the global state is set correctly for this
1571 context_switch (ecs
->ptid
);
1573 /* Now figure out what to do with the result of the result. */
1574 handle_inferior_event (ecs
);
1576 if (!ecs
->wait_some_more
)
1578 delete_step_resume_breakpoint (&step_resume_breakpoint
);
1581 if (step_multi
&& stop_step
)
1582 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
1584 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
1587 /* Revert thread and frame. */
1588 do_cleanups (old_chain
);
1590 /* If the inferior was in sync execution mode, and now isn't,
1591 restore the prompt. */
1592 if (was_sync
&& !sync_execution
)
1593 display_gdb_prompt (0);
1596 /* Prepare an execution control state for looping through a
1597 wait_for_inferior-type loop. */
1600 init_execution_control_state (struct execution_control_state
*ecs
)
1602 ecs
->random_signal
= 0;
1605 /* Clear context switchable stepping state. */
1608 init_thread_stepping_state (struct thread_stepping_state
*tss
)
1610 struct symtab_and_line sal
;
1612 tss
->stepping_over_breakpoint
= 0;
1613 tss
->step_after_step_resume_breakpoint
= 0;
1614 tss
->stepping_through_solib_after_catch
= 0;
1615 tss
->stepping_through_solib_catchpoints
= NULL
;
1617 sal
= find_pc_line (prev_pc
, 0);
1618 tss
->current_line
= sal
.line
;
1619 tss
->current_symtab
= sal
.symtab
;
1622 /* Return the cached copy of the last pid/waitstatus returned by
1623 target_wait()/deprecated_target_wait_hook(). The data is actually
1624 cached by handle_inferior_event(), which gets called immediately
1625 after target_wait()/deprecated_target_wait_hook(). */
1628 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
1630 *ptidp
= target_last_wait_ptid
;
1631 *status
= target_last_waitstatus
;
1635 nullify_last_target_wait_ptid (void)
1637 target_last_wait_ptid
= minus_one_ptid
;
1640 /* Switch thread contexts, maintaining "infrun state". */
1643 context_switch (ptid_t ptid
)
1645 /* Caution: it may happen that the new thread (or the old one!)
1646 is not in the thread list. In this case we must not attempt
1647 to "switch context", or we run the risk that our context may
1648 be lost. This may happen as a result of the target module
1649 mishandling thread creation. */
1653 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
1654 target_pid_to_str (inferior_ptid
));
1655 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
1656 target_pid_to_str (ptid
));
1659 if (in_thread_list (inferior_ptid
) && in_thread_list (ptid
))
1660 { /* Perform infrun state context switch: */
1661 /* Save infrun state for the old thread. */
1662 save_infrun_state (inferior_ptid
, prev_pc
,
1663 stepping_over_breakpoint
, step_resume_breakpoint
,
1665 step_range_end
, &step_frame_id
,
1666 tss
->stepping_over_breakpoint
,
1667 tss
->stepping_through_solib_after_catch
,
1668 tss
->stepping_through_solib_catchpoints
,
1669 tss
->current_line
, tss
->current_symtab
,
1670 cmd_continuation
, intermediate_continuation
,
1678 /* Load infrun state for the new thread. */
1679 load_infrun_state (ptid
, &prev_pc
,
1680 &stepping_over_breakpoint
, &step_resume_breakpoint
,
1682 &step_range_end
, &step_frame_id
,
1683 &tss
->stepping_over_breakpoint
,
1684 &tss
->stepping_through_solib_after_catch
,
1685 &tss
->stepping_through_solib_catchpoints
,
1686 &tss
->current_line
, &tss
->current_symtab
,
1687 &cmd_continuation
, &intermediate_continuation
,
1696 switch_to_thread (ptid
);
1699 /* Context switch to thread PTID. */
1701 context_switch_to (ptid_t ptid
)
1703 ptid_t current_ptid
= inferior_ptid
;
1705 /* Context switch to the new thread. */
1706 if (!ptid_equal (ptid
, inferior_ptid
))
1708 context_switch (ptid
);
1710 return current_ptid
;
1714 adjust_pc_after_break (struct execution_control_state
*ecs
)
1716 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
1717 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1718 CORE_ADDR breakpoint_pc
;
1720 /* If this target does not decrement the PC after breakpoints, then
1721 we have nothing to do. */
1722 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
1725 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
1726 we aren't, just return.
1728 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
1729 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
1730 implemented by software breakpoints should be handled through the normal
1733 NOTE drow/2004-01-31: On some targets, breakpoints may generate
1734 different signals (SIGILL or SIGEMT for instance), but it is less
1735 clear where the PC is pointing afterwards. It may not match
1736 gdbarch_decr_pc_after_break. I don't know any specific target that
1737 generates these signals at breakpoints (the code has been in GDB since at
1738 least 1992) so I can not guess how to handle them here.
1740 In earlier versions of GDB, a target with
1741 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
1742 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
1743 target with both of these set in GDB history, and it seems unlikely to be
1744 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
1746 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
1749 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1752 /* Find the location where (if we've hit a breakpoint) the
1753 breakpoint would be. */
1754 breakpoint_pc
= regcache_read_pc (regcache
)
1755 - gdbarch_decr_pc_after_break (gdbarch
);
1757 /* Check whether there actually is a software breakpoint inserted
1758 at that location. */
1759 if (software_breakpoint_inserted_here_p (breakpoint_pc
))
1761 /* When using hardware single-step, a SIGTRAP is reported for both
1762 a completed single-step and a software breakpoint. Need to
1763 differentiate between the two, as the latter needs adjusting
1764 but the former does not.
1766 The SIGTRAP can be due to a completed hardware single-step only if
1767 - we didn't insert software single-step breakpoints
1768 - the thread to be examined is still the current thread
1769 - this thread is currently being stepped
1771 If any of these events did not occur, we must have stopped due
1772 to hitting a software breakpoint, and have to back up to the
1775 As a special case, we could have hardware single-stepped a
1776 software breakpoint. In this case (prev_pc == breakpoint_pc),
1777 we also need to back up to the breakpoint address. */
1779 if (singlestep_breakpoints_inserted_p
1780 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
1781 || !currently_stepping (tss
)
1782 || prev_pc
== breakpoint_pc
)
1783 regcache_write_pc (regcache
, breakpoint_pc
);
1788 init_infwait_state (void)
1790 waiton_ptid
= pid_to_ptid (-1);
1791 infwait_state
= infwait_normal_state
;
1795 error_is_running (void)
1798 Cannot execute this command while the selected thread is running."));
1802 ensure_not_running (void)
1804 if (is_running (inferior_ptid
))
1805 error_is_running ();
1808 /* Given an execution control state that has been freshly filled in
1809 by an event from the inferior, figure out what it means and take
1810 appropriate action. */
1813 handle_inferior_event (struct execution_control_state
*ecs
)
1815 int sw_single_step_trap_p
= 0;
1816 int stopped_by_watchpoint
;
1817 int stepped_after_stopped_by_watchpoint
= 0;
1818 struct symtab_and_line stop_pc_sal
;
1820 breakpoint_retire_moribund ();
1822 /* Cache the last pid/waitstatus. */
1823 target_last_wait_ptid
= ecs
->ptid
;
1824 target_last_waitstatus
= ecs
->ws
;
1826 /* Always clear state belonging to the previous time we stopped. */
1827 stop_stack_dummy
= 0;
1829 adjust_pc_after_break (ecs
);
1831 reinit_frame_cache ();
1833 /* If it's a new process, add it to the thread database */
1835 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
1836 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
1837 && !in_thread_list (ecs
->ptid
));
1839 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1840 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
1841 add_thread (ecs
->ptid
);
1843 if (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
1845 /* Mark the non-executing threads accordingly. */
1847 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
1848 || ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
1849 set_executing (pid_to_ptid (-1), 0);
1851 set_executing (ecs
->ptid
, 0);
1854 switch (infwait_state
)
1856 case infwait_thread_hop_state
:
1858 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
1859 /* Cancel the waiton_ptid. */
1860 waiton_ptid
= pid_to_ptid (-1);
1863 case infwait_normal_state
:
1865 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
1868 case infwait_step_watch_state
:
1870 fprintf_unfiltered (gdb_stdlog
,
1871 "infrun: infwait_step_watch_state\n");
1873 stepped_after_stopped_by_watchpoint
= 1;
1876 case infwait_nonstep_watch_state
:
1878 fprintf_unfiltered (gdb_stdlog
,
1879 "infrun: infwait_nonstep_watch_state\n");
1880 insert_breakpoints ();
1882 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1883 handle things like signals arriving and other things happening
1884 in combination correctly? */
1885 stepped_after_stopped_by_watchpoint
= 1;
1889 internal_error (__FILE__
, __LINE__
, _("bad switch"));
1891 infwait_state
= infwait_normal_state
;
1893 switch (ecs
->ws
.kind
)
1895 case TARGET_WAITKIND_LOADED
:
1897 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
1898 /* Ignore gracefully during startup of the inferior, as it might
1899 be the shell which has just loaded some objects, otherwise
1900 add the symbols for the newly loaded objects. Also ignore at
1901 the beginning of an attach or remote session; we will query
1902 the full list of libraries once the connection is
1904 if (stop_soon
== NO_STOP_QUIETLY
)
1906 /* Check for any newly added shared libraries if we're
1907 supposed to be adding them automatically. Switch
1908 terminal for any messages produced by
1909 breakpoint_re_set. */
1910 target_terminal_ours_for_output ();
1911 /* NOTE: cagney/2003-11-25: Make certain that the target
1912 stack's section table is kept up-to-date. Architectures,
1913 (e.g., PPC64), use the section table to perform
1914 operations such as address => section name and hence
1915 require the table to contain all sections (including
1916 those found in shared libraries). */
1917 /* NOTE: cagney/2003-11-25: Pass current_target and not
1918 exec_ops to SOLIB_ADD. This is because current GDB is
1919 only tooled to propagate section_table changes out from
1920 the "current_target" (see target_resize_to_sections), and
1921 not up from the exec stratum. This, of course, isn't
1922 right. "infrun.c" should only interact with the
1923 exec/process stratum, instead relying on the target stack
1924 to propagate relevant changes (stop, section table
1925 changed, ...) up to other layers. */
1927 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
1929 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
1931 target_terminal_inferior ();
1933 /* If requested, stop when the dynamic linker notifies
1934 gdb of events. This allows the user to get control
1935 and place breakpoints in initializer routines for
1936 dynamically loaded objects (among other things). */
1937 if (stop_on_solib_events
)
1939 stop_stepping (ecs
);
1943 /* NOTE drow/2007-05-11: This might be a good place to check
1944 for "catch load". */
1947 /* If we are skipping through a shell, or through shared library
1948 loading that we aren't interested in, resume the program. If
1949 we're running the program normally, also resume. But stop if
1950 we're attaching or setting up a remote connection. */
1951 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
1953 /* Loading of shared libraries might have changed breakpoint
1954 addresses. Make sure new breakpoints are inserted. */
1955 if (stop_soon
== NO_STOP_QUIETLY
1956 && !breakpoints_always_inserted_mode ())
1957 insert_breakpoints ();
1958 resume (0, TARGET_SIGNAL_0
);
1959 prepare_to_wait (ecs
);
1965 case TARGET_WAITKIND_SPURIOUS
:
1967 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
1968 resume (0, TARGET_SIGNAL_0
);
1969 prepare_to_wait (ecs
);
1972 case TARGET_WAITKIND_EXITED
:
1974 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
1975 target_terminal_ours (); /* Must do this before mourn anyway */
1976 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
1978 /* Record the exit code in the convenience variable $_exitcode, so
1979 that the user can inspect this again later. */
1980 set_internalvar (lookup_internalvar ("_exitcode"),
1981 value_from_longest (builtin_type_int
,
1982 (LONGEST
) ecs
->ws
.value
.integer
));
1983 gdb_flush (gdb_stdout
);
1984 target_mourn_inferior ();
1985 singlestep_breakpoints_inserted_p
= 0;
1986 stop_print_frame
= 0;
1987 stop_stepping (ecs
);
1990 case TARGET_WAITKIND_SIGNALLED
:
1992 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
1993 stop_print_frame
= 0;
1994 stop_signal
= ecs
->ws
.value
.sig
;
1995 target_terminal_ours (); /* Must do this before mourn anyway */
1997 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
1998 reach here unless the inferior is dead. However, for years
1999 target_kill() was called here, which hints that fatal signals aren't
2000 really fatal on some systems. If that's true, then some changes
2002 target_mourn_inferior ();
2004 print_stop_reason (SIGNAL_EXITED
, stop_signal
);
2005 singlestep_breakpoints_inserted_p
= 0;
2006 stop_stepping (ecs
);
2009 /* The following are the only cases in which we keep going;
2010 the above cases end in a continue or goto. */
2011 case TARGET_WAITKIND_FORKED
:
2012 case TARGET_WAITKIND_VFORKED
:
2014 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2015 stop_signal
= TARGET_SIGNAL_TRAP
;
2016 pending_follow
.kind
= ecs
->ws
.kind
;
2018 pending_follow
.fork_event
.parent_pid
= ecs
->ptid
;
2019 pending_follow
.fork_event
.child_pid
= ecs
->ws
.value
.related_pid
;
2021 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2023 context_switch (ecs
->ptid
);
2024 reinit_frame_cache ();
2027 stop_pc
= read_pc ();
2029 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2031 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2033 /* If no catchpoint triggered for this, then keep going. */
2034 if (ecs
->random_signal
)
2036 stop_signal
= TARGET_SIGNAL_0
;
2040 goto process_event_stop_test
;
2042 case TARGET_WAITKIND_EXECD
:
2044 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
2045 stop_signal
= TARGET_SIGNAL_TRAP
;
2047 pending_follow
.execd_pathname
=
2048 savestring (ecs
->ws
.value
.execd_pathname
,
2049 strlen (ecs
->ws
.value
.execd_pathname
));
2051 /* This causes the eventpoints and symbol table to be reset. Must
2052 do this now, before trying to determine whether to stop. */
2053 follow_exec (inferior_ptid
, pending_follow
.execd_pathname
);
2054 xfree (pending_follow
.execd_pathname
);
2056 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2059 /* The breakpoints module may need to touch the inferior's
2060 memory. Switch to the (stopped) event ptid
2062 ptid_t saved_inferior_ptid
= inferior_ptid
;
2063 inferior_ptid
= ecs
->ptid
;
2065 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2067 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2068 inferior_ptid
= saved_inferior_ptid
;
2071 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2073 context_switch (ecs
->ptid
);
2074 reinit_frame_cache ();
2077 /* If no catchpoint triggered for this, then keep going. */
2078 if (ecs
->random_signal
)
2080 stop_signal
= TARGET_SIGNAL_0
;
2084 goto process_event_stop_test
;
2086 /* Be careful not to try to gather much state about a thread
2087 that's in a syscall. It's frequently a losing proposition. */
2088 case TARGET_WAITKIND_SYSCALL_ENTRY
:
2090 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2091 resume (0, TARGET_SIGNAL_0
);
2092 prepare_to_wait (ecs
);
2095 /* Before examining the threads further, step this thread to
2096 get it entirely out of the syscall. (We get notice of the
2097 event when the thread is just on the verge of exiting a
2098 syscall. Stepping one instruction seems to get it back
2100 case TARGET_WAITKIND_SYSCALL_RETURN
:
2102 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2103 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
);
2104 prepare_to_wait (ecs
);
2107 case TARGET_WAITKIND_STOPPED
:
2109 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
2110 stop_signal
= ecs
->ws
.value
.sig
;
2113 /* We had an event in the inferior, but we are not interested
2114 in handling it at this level. The lower layers have already
2115 done what needs to be done, if anything.
2117 One of the possible circumstances for this is when the
2118 inferior produces output for the console. The inferior has
2119 not stopped, and we are ignoring the event. Another possible
2120 circumstance is any event which the lower level knows will be
2121 reported multiple times without an intervening resume. */
2122 case TARGET_WAITKIND_IGNORE
:
2124 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2125 prepare_to_wait (ecs
);
2129 if (ecs
->new_thread_event
)
2132 /* Non-stop assumes that the target handles adding new threads
2133 to the thread list. */
2134 internal_error (__FILE__
, __LINE__
, "\
2135 targets should add new threads to the thread list themselves in non-stop mode.");
2137 /* We may want to consider not doing a resume here in order to
2138 give the user a chance to play with the new thread. It might
2139 be good to make that a user-settable option. */
2141 /* At this point, all threads are stopped (happens automatically
2142 in either the OS or the native code). Therefore we need to
2143 continue all threads in order to make progress. */
2145 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
2146 prepare_to_wait (ecs
);
2150 /* Do we need to clean up the state of a thread that has completed a
2151 displaced single-step? (Doing so usually affects the PC, so do
2152 it here, before we set stop_pc.) */
2153 displaced_step_fixup (ecs
->ptid
, stop_signal
);
2155 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2159 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = 0x%s\n",
2160 paddr_nz (stop_pc
));
2161 if (STOPPED_BY_WATCHPOINT (&ecs
->ws
))
2164 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
2166 if (target_stopped_data_address (¤t_target
, &addr
))
2167 fprintf_unfiltered (gdb_stdlog
,
2168 "infrun: stopped data address = 0x%s\n",
2171 fprintf_unfiltered (gdb_stdlog
,
2172 "infrun: (no data address available)\n");
2176 if (stepping_past_singlestep_breakpoint
)
2178 gdb_assert (singlestep_breakpoints_inserted_p
);
2179 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
2180 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
2182 stepping_past_singlestep_breakpoint
= 0;
2184 /* We've either finished single-stepping past the single-step
2185 breakpoint, or stopped for some other reason. It would be nice if
2186 we could tell, but we can't reliably. */
2187 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2190 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
2191 /* Pull the single step breakpoints out of the target. */
2192 remove_single_step_breakpoints ();
2193 singlestep_breakpoints_inserted_p
= 0;
2195 ecs
->random_signal
= 0;
2197 context_switch (saved_singlestep_ptid
);
2198 if (deprecated_context_hook
)
2199 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2201 resume (1, TARGET_SIGNAL_0
);
2202 prepare_to_wait (ecs
);
2207 stepping_past_singlestep_breakpoint
= 0;
2209 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
2211 /* In non-stop mode, there's never a deferred_step_ptid set. */
2212 gdb_assert (!non_stop
);
2214 /* If we stopped for some other reason than single-stepping, ignore
2215 the fact that we were supposed to switch back. */
2216 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2219 fprintf_unfiltered (gdb_stdlog
,
2220 "infrun: handling deferred step\n");
2222 /* Pull the single step breakpoints out of the target. */
2223 if (singlestep_breakpoints_inserted_p
)
2225 remove_single_step_breakpoints ();
2226 singlestep_breakpoints_inserted_p
= 0;
2229 /* Note: We do not call context_switch at this point, as the
2230 context is already set up for stepping the original thread. */
2231 switch_to_thread (deferred_step_ptid
);
2232 deferred_step_ptid
= null_ptid
;
2233 /* Suppress spurious "Switching to ..." message. */
2234 previous_inferior_ptid
= inferior_ptid
;
2236 resume (1, TARGET_SIGNAL_0
);
2237 prepare_to_wait (ecs
);
2241 deferred_step_ptid
= null_ptid
;
2244 /* See if a thread hit a thread-specific breakpoint that was meant for
2245 another thread. If so, then step that thread past the breakpoint,
2248 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2250 int thread_hop_needed
= 0;
2252 /* Check if a regular breakpoint has been hit before checking
2253 for a potential single step breakpoint. Otherwise, GDB will
2254 not see this breakpoint hit when stepping onto breakpoints. */
2255 if (regular_breakpoint_inserted_here_p (stop_pc
))
2257 ecs
->random_signal
= 0;
2258 if (!breakpoint_thread_match (stop_pc
, ecs
->ptid
))
2259 thread_hop_needed
= 1;
2261 else if (singlestep_breakpoints_inserted_p
)
2263 /* We have not context switched yet, so this should be true
2264 no matter which thread hit the singlestep breakpoint. */
2265 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
2267 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
2269 target_pid_to_str (ecs
->ptid
));
2271 ecs
->random_signal
= 0;
2272 /* The call to in_thread_list is necessary because PTIDs sometimes
2273 change when we go from single-threaded to multi-threaded. If
2274 the singlestep_ptid is still in the list, assume that it is
2275 really different from ecs->ptid. */
2276 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
2277 && in_thread_list (singlestep_ptid
))
2279 /* If the PC of the thread we were trying to single-step
2280 has changed, discard this event (which we were going
2281 to ignore anyway), and pretend we saw that thread
2282 trap. This prevents us continuously moving the
2283 single-step breakpoint forward, one instruction at a
2284 time. If the PC has changed, then the thread we were
2285 trying to single-step has trapped or been signalled,
2286 but the event has not been reported to GDB yet.
2288 There might be some cases where this loses signal
2289 information, if a signal has arrived at exactly the
2290 same time that the PC changed, but this is the best
2291 we can do with the information available. Perhaps we
2292 should arrange to report all events for all threads
2293 when they stop, or to re-poll the remote looking for
2294 this particular thread (i.e. temporarily enable
2297 CORE_ADDR new_singlestep_pc
2298 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
2300 if (new_singlestep_pc
!= singlestep_pc
)
2303 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
2304 " but expected thread advanced also\n");
2306 /* The current context still belongs to
2307 singlestep_ptid. Don't swap here, since that's
2308 the context we want to use. Just fudge our
2309 state and continue. */
2310 ecs
->ptid
= singlestep_ptid
;
2311 stop_pc
= new_singlestep_pc
;
2316 fprintf_unfiltered (gdb_stdlog
,
2317 "infrun: unexpected thread\n");
2319 thread_hop_needed
= 1;
2320 stepping_past_singlestep_breakpoint
= 1;
2321 saved_singlestep_ptid
= singlestep_ptid
;
2326 if (thread_hop_needed
)
2328 int remove_status
= 0;
2331 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
2333 /* Saw a breakpoint, but it was hit by the wrong thread.
2336 if (singlestep_breakpoints_inserted_p
)
2338 /* Pull the single step breakpoints out of the target. */
2339 remove_single_step_breakpoints ();
2340 singlestep_breakpoints_inserted_p
= 0;
2343 /* If the arch can displace step, don't remove the
2345 if (!use_displaced_stepping (current_gdbarch
))
2346 remove_status
= remove_breakpoints ();
2348 /* Did we fail to remove breakpoints? If so, try
2349 to set the PC past the bp. (There's at least
2350 one situation in which we can fail to remove
2351 the bp's: On HP-UX's that use ttrace, we can't
2352 change the address space of a vforking child
2353 process until the child exits (well, okay, not
2354 then either :-) or execs. */
2355 if (remove_status
!= 0)
2356 error (_("Cannot step over breakpoint hit in wrong thread"));
2359 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
2360 context_switch (ecs
->ptid
);
2364 /* Only need to require the next event from this
2365 thread in all-stop mode. */
2366 waiton_ptid
= ecs
->ptid
;
2367 infwait_state
= infwait_thread_hop_state
;
2370 tss
->stepping_over_breakpoint
= 1;
2372 registers_changed ();
2376 else if (singlestep_breakpoints_inserted_p
)
2378 sw_single_step_trap_p
= 1;
2379 ecs
->random_signal
= 0;
2383 ecs
->random_signal
= 1;
2385 /* See if something interesting happened to the non-current thread. If
2386 so, then switch to that thread. */
2387 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2390 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
2392 context_switch (ecs
->ptid
);
2394 if (deprecated_context_hook
)
2395 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2398 if (singlestep_breakpoints_inserted_p
)
2400 /* Pull the single step breakpoints out of the target. */
2401 remove_single_step_breakpoints ();
2402 singlestep_breakpoints_inserted_p
= 0;
2405 if (stepped_after_stopped_by_watchpoint
)
2406 stopped_by_watchpoint
= 0;
2408 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
2410 /* If necessary, step over this watchpoint. We'll be back to display
2412 if (stopped_by_watchpoint
2413 && (HAVE_STEPPABLE_WATCHPOINT
2414 || gdbarch_have_nonsteppable_watchpoint (current_gdbarch
)))
2416 /* At this point, we are stopped at an instruction which has
2417 attempted to write to a piece of memory under control of
2418 a watchpoint. The instruction hasn't actually executed
2419 yet. If we were to evaluate the watchpoint expression
2420 now, we would get the old value, and therefore no change
2421 would seem to have occurred.
2423 In order to make watchpoints work `right', we really need
2424 to complete the memory write, and then evaluate the
2425 watchpoint expression. We do this by single-stepping the
2428 It may not be necessary to disable the watchpoint to stop over
2429 it. For example, the PA can (with some kernel cooperation)
2430 single step over a watchpoint without disabling the watchpoint.
2432 It is far more common to need to disable a watchpoint to step
2433 the inferior over it. If we have non-steppable watchpoints,
2434 we must disable the current watchpoint; it's simplest to
2435 disable all watchpoints and breakpoints. */
2437 if (!HAVE_STEPPABLE_WATCHPOINT
)
2438 remove_breakpoints ();
2439 registers_changed ();
2440 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
); /* Single step */
2441 waiton_ptid
= ecs
->ptid
;
2442 if (HAVE_STEPPABLE_WATCHPOINT
)
2443 infwait_state
= infwait_step_watch_state
;
2445 infwait_state
= infwait_nonstep_watch_state
;
2446 prepare_to_wait (ecs
);
2450 ecs
->stop_func_start
= 0;
2451 ecs
->stop_func_end
= 0;
2452 ecs
->stop_func_name
= 0;
2453 /* Don't care about return value; stop_func_start and stop_func_name
2454 will both be 0 if it doesn't work. */
2455 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
2456 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
2457 ecs
->stop_func_start
2458 += gdbarch_deprecated_function_start_offset (current_gdbarch
);
2459 tss
->stepping_over_breakpoint
= 0;
2460 bpstat_clear (&stop_bpstat
);
2462 stop_print_frame
= 1;
2463 ecs
->random_signal
= 0;
2464 stopped_by_random_signal
= 0;
2466 if (stop_signal
== TARGET_SIGNAL_TRAP
2467 && stepping_over_breakpoint
2468 && gdbarch_single_step_through_delay_p (current_gdbarch
)
2469 && currently_stepping (tss
))
2471 /* We're trying to step off a breakpoint. Turns out that we're
2472 also on an instruction that needs to be stepped multiple
2473 times before it's been fully executing. E.g., architectures
2474 with a delay slot. It needs to be stepped twice, once for
2475 the instruction and once for the delay slot. */
2476 int step_through_delay
2477 = gdbarch_single_step_through_delay (current_gdbarch
,
2478 get_current_frame ());
2479 if (debug_infrun
&& step_through_delay
)
2480 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
2481 if (step_range_end
== 0 && step_through_delay
)
2483 /* The user issued a continue when stopped at a breakpoint.
2484 Set up for another trap and get out of here. */
2485 tss
->stepping_over_breakpoint
= 1;
2489 else if (step_through_delay
)
2491 /* The user issued a step when stopped at a breakpoint.
2492 Maybe we should stop, maybe we should not - the delay
2493 slot *might* correspond to a line of source. In any
2494 case, don't decide that here, just set
2495 ecs->stepping_over_breakpoint, making sure we
2496 single-step again before breakpoints are re-inserted. */
2497 tss
->stepping_over_breakpoint
= 1;
2501 /* Look at the cause of the stop, and decide what to do.
2502 The alternatives are:
2503 1) stop_stepping and return; to really stop and return to the debugger,
2504 2) keep_going and return to start up again
2505 (set tss->stepping_over_breakpoint to 1 to single step once)
2506 3) set ecs->random_signal to 1, and the decision between 1 and 2
2507 will be made according to the signal handling tables. */
2509 /* First, distinguish signals caused by the debugger from signals
2510 that have to do with the program's own actions. Note that
2511 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
2512 on the operating system version. Here we detect when a SIGILL or
2513 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
2514 something similar for SIGSEGV, since a SIGSEGV will be generated
2515 when we're trying to execute a breakpoint instruction on a
2516 non-executable stack. This happens for call dummy breakpoints
2517 for architectures like SPARC that place call dummies on the
2520 If we're doing a displaced step past a breakpoint, then the
2521 breakpoint is always inserted at the original instruction;
2522 non-standard signals can't be explained by the breakpoint. */
2523 if (stop_signal
== TARGET_SIGNAL_TRAP
2524 || (! stepping_over_breakpoint
2525 && breakpoint_inserted_here_p (stop_pc
)
2526 && (stop_signal
== TARGET_SIGNAL_ILL
2527 || stop_signal
== TARGET_SIGNAL_SEGV
2528 || stop_signal
== TARGET_SIGNAL_EMT
))
2529 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2530 || stop_soon
== STOP_QUIETLY_REMOTE
)
2532 if (stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
2535 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
2536 stop_print_frame
= 0;
2537 stop_stepping (ecs
);
2541 /* This is originated from start_remote(), start_inferior() and
2542 shared libraries hook functions. */
2543 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
2546 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
2547 stop_stepping (ecs
);
2551 /* This originates from attach_command(). We need to overwrite
2552 the stop_signal here, because some kernels don't ignore a
2553 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
2554 See more comments in inferior.h. On the other hand, if we
2555 get a non-SIGSTOP, report it to the user - assume the backend
2556 will handle the SIGSTOP if it should show up later.
2558 Also consider that the attach is complete when we see a
2559 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
2560 target extended-remote report it instead of a SIGSTOP
2561 (e.g. gdbserver). We already rely on SIGTRAP being our
2562 signal, so this is no exception. */
2563 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2564 && (stop_signal
== TARGET_SIGNAL_STOP
2565 || stop_signal
== TARGET_SIGNAL_TRAP
))
2567 stop_stepping (ecs
);
2568 stop_signal
= TARGET_SIGNAL_0
;
2572 /* See if there is a breakpoint at the current PC. */
2573 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2575 /* Following in case break condition called a
2577 stop_print_frame
= 1;
2579 /* NOTE: cagney/2003-03-29: These two checks for a random signal
2580 at one stage in the past included checks for an inferior
2581 function call's call dummy's return breakpoint. The original
2582 comment, that went with the test, read:
2584 ``End of a stack dummy. Some systems (e.g. Sony news) give
2585 another signal besides SIGTRAP, so check here as well as
2588 If someone ever tries to get get call dummys on a
2589 non-executable stack to work (where the target would stop
2590 with something like a SIGSEGV), then those tests might need
2591 to be re-instated. Given, however, that the tests were only
2592 enabled when momentary breakpoints were not being used, I
2593 suspect that it won't be the case.
2595 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
2596 be necessary for call dummies on a non-executable stack on
2599 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2601 = !(bpstat_explains_signal (stop_bpstat
)
2602 || stepping_over_breakpoint
2603 || (step_range_end
&& step_resume_breakpoint
== NULL
));
2606 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2607 if (!ecs
->random_signal
)
2608 stop_signal
= TARGET_SIGNAL_TRAP
;
2612 /* When we reach this point, we've pretty much decided
2613 that the reason for stopping must've been a random
2614 (unexpected) signal. */
2617 ecs
->random_signal
= 1;
2619 process_event_stop_test
:
2620 /* For the program's own signals, act according to
2621 the signal handling tables. */
2623 if (ecs
->random_signal
)
2625 /* Signal not for debugging purposes. */
2629 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n", stop_signal
);
2631 stopped_by_random_signal
= 1;
2633 if (signal_print
[stop_signal
])
2636 target_terminal_ours_for_output ();
2637 print_stop_reason (SIGNAL_RECEIVED
, stop_signal
);
2639 if (signal_stop_state (stop_signal
))
2641 stop_stepping (ecs
);
2644 /* If not going to stop, give terminal back
2645 if we took it away. */
2647 target_terminal_inferior ();
2649 /* Clear the signal if it should not be passed. */
2650 if (signal_program
[stop_signal
] == 0)
2651 stop_signal
= TARGET_SIGNAL_0
;
2653 if (prev_pc
== read_pc ()
2654 && stepping_over_breakpoint
2655 && step_resume_breakpoint
== NULL
)
2657 /* We were just starting a new sequence, attempting to
2658 single-step off of a breakpoint and expecting a SIGTRAP.
2659 Instead this signal arrives. This signal will take us out
2660 of the stepping range so GDB needs to remember to, when
2661 the signal handler returns, resume stepping off that
2663 /* To simplify things, "continue" is forced to use the same
2664 code paths as single-step - set a breakpoint at the
2665 signal return address and then, once hit, step off that
2668 fprintf_unfiltered (gdb_stdlog
,
2669 "infrun: signal arrived while stepping over "
2672 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2673 tss
->step_after_step_resume_breakpoint
= 1;
2678 if (step_range_end
!= 0
2679 && stop_signal
!= TARGET_SIGNAL_0
2680 && stop_pc
>= step_range_start
&& stop_pc
< step_range_end
2681 && frame_id_eq (get_frame_id (get_current_frame ()),
2683 && step_resume_breakpoint
== NULL
)
2685 /* The inferior is about to take a signal that will take it
2686 out of the single step range. Set a breakpoint at the
2687 current PC (which is presumably where the signal handler
2688 will eventually return) and then allow the inferior to
2691 Note that this is only needed for a signal delivered
2692 while in the single-step range. Nested signals aren't a
2693 problem as they eventually all return. */
2695 fprintf_unfiltered (gdb_stdlog
,
2696 "infrun: signal may take us out of "
2697 "single-step range\n");
2699 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2704 /* Note: step_resume_breakpoint may be non-NULL. This occures
2705 when either there's a nested signal, or when there's a
2706 pending signal enabled just as the signal handler returns
2707 (leaving the inferior at the step-resume-breakpoint without
2708 actually executing it). Either way continue until the
2709 breakpoint is really hit. */
2714 /* Handle cases caused by hitting a breakpoint. */
2716 CORE_ADDR jmp_buf_pc
;
2717 struct bpstat_what what
;
2719 what
= bpstat_what (stop_bpstat
);
2721 if (what
.call_dummy
)
2723 stop_stack_dummy
= 1;
2726 switch (what
.main_action
)
2728 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
2729 /* If we hit the breakpoint at longjmp while stepping, we
2730 install a momentary breakpoint at the target of the
2734 fprintf_unfiltered (gdb_stdlog
,
2735 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
2737 tss
->stepping_over_breakpoint
= 1;
2739 if (!gdbarch_get_longjmp_target_p (current_gdbarch
)
2740 || !gdbarch_get_longjmp_target (current_gdbarch
,
2741 get_current_frame (), &jmp_buf_pc
))
2744 fprintf_unfiltered (gdb_stdlog
, "\
2745 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
2750 /* We're going to replace the current step-resume breakpoint
2751 with a longjmp-resume breakpoint. */
2752 if (step_resume_breakpoint
!= NULL
)
2753 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2755 /* Insert a breakpoint at resume address. */
2756 insert_longjmp_resume_breakpoint (jmp_buf_pc
);
2761 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
2763 fprintf_unfiltered (gdb_stdlog
,
2764 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
2766 gdb_assert (step_resume_breakpoint
!= NULL
);
2767 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2770 print_stop_reason (END_STEPPING_RANGE
, 0);
2771 stop_stepping (ecs
);
2774 case BPSTAT_WHAT_SINGLE
:
2776 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
2777 tss
->stepping_over_breakpoint
= 1;
2778 /* Still need to check other stuff, at least the case
2779 where we are stepping and step out of the right range. */
2782 case BPSTAT_WHAT_STOP_NOISY
:
2784 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
2785 stop_print_frame
= 1;
2787 /* We are about to nuke the step_resume_breakpointt via the
2788 cleanup chain, so no need to worry about it here. */
2790 stop_stepping (ecs
);
2793 case BPSTAT_WHAT_STOP_SILENT
:
2795 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
2796 stop_print_frame
= 0;
2798 /* We are about to nuke the step_resume_breakpoin via the
2799 cleanup chain, so no need to worry about it here. */
2801 stop_stepping (ecs
);
2804 case BPSTAT_WHAT_STEP_RESUME
:
2805 /* This proably demands a more elegant solution, but, yeah
2808 This function's use of the simple variable
2809 step_resume_breakpoint doesn't seem to accomodate
2810 simultaneously active step-resume bp's, although the
2811 breakpoint list certainly can.
2813 If we reach here and step_resume_breakpoint is already
2814 NULL, then apparently we have multiple active
2815 step-resume bp's. We'll just delete the breakpoint we
2816 stopped at, and carry on.
2818 Correction: what the code currently does is delete a
2819 step-resume bp, but it makes no effort to ensure that
2820 the one deleted is the one currently stopped at. MVS */
2823 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
2825 if (step_resume_breakpoint
== NULL
)
2827 step_resume_breakpoint
=
2828 bpstat_find_step_resume_breakpoint (stop_bpstat
);
2830 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2831 if (tss
->step_after_step_resume_breakpoint
)
2833 /* Back when the step-resume breakpoint was inserted, we
2834 were trying to single-step off a breakpoint. Go back
2836 tss
->step_after_step_resume_breakpoint
= 0;
2837 tss
->stepping_over_breakpoint
= 1;
2843 case BPSTAT_WHAT_CHECK_SHLIBS
:
2844 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
:
2847 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
2849 /* Check for any newly added shared libraries if we're
2850 supposed to be adding them automatically. Switch
2851 terminal for any messages produced by
2852 breakpoint_re_set. */
2853 target_terminal_ours_for_output ();
2854 /* NOTE: cagney/2003-11-25: Make certain that the target
2855 stack's section table is kept up-to-date. Architectures,
2856 (e.g., PPC64), use the section table to perform
2857 operations such as address => section name and hence
2858 require the table to contain all sections (including
2859 those found in shared libraries). */
2860 /* NOTE: cagney/2003-11-25: Pass current_target and not
2861 exec_ops to SOLIB_ADD. This is because current GDB is
2862 only tooled to propagate section_table changes out from
2863 the "current_target" (see target_resize_to_sections), and
2864 not up from the exec stratum. This, of course, isn't
2865 right. "infrun.c" should only interact with the
2866 exec/process stratum, instead relying on the target stack
2867 to propagate relevant changes (stop, section table
2868 changed, ...) up to other layers. */
2870 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2872 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2874 target_terminal_inferior ();
2876 /* If requested, stop when the dynamic linker notifies
2877 gdb of events. This allows the user to get control
2878 and place breakpoints in initializer routines for
2879 dynamically loaded objects (among other things). */
2880 if (stop_on_solib_events
|| stop_stack_dummy
)
2882 stop_stepping (ecs
);
2886 /* If we stopped due to an explicit catchpoint, then the
2887 (see above) call to SOLIB_ADD pulled in any symbols
2888 from a newly-loaded library, if appropriate.
2890 We do want the inferior to stop, but not where it is
2891 now, which is in the dynamic linker callback. Rather,
2892 we would like it stop in the user's program, just after
2893 the call that caused this catchpoint to trigger. That
2894 gives the user a more useful vantage from which to
2895 examine their program's state. */
2896 else if (what
.main_action
2897 == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
)
2899 /* ??rehrauer: If I could figure out how to get the
2900 right return PC from here, we could just set a temp
2901 breakpoint and resume. I'm not sure we can without
2902 cracking open the dld's shared libraries and sniffing
2903 their unwind tables and text/data ranges, and that's
2904 not a terribly portable notion.
2906 Until that time, we must step the inferior out of the
2907 dld callback, and also out of the dld itself (and any
2908 code or stubs in libdld.sl, such as "shl_load" and
2909 friends) until we reach non-dld code. At that point,
2910 we can stop stepping. */
2911 bpstat_get_triggered_catchpoints (stop_bpstat
,
2913 stepping_through_solib_catchpoints
);
2914 tss
->stepping_through_solib_after_catch
= 1;
2916 /* Be sure to lift all breakpoints, so the inferior does
2917 actually step past this point... */
2918 tss
->stepping_over_breakpoint
= 1;
2923 /* We want to step over this breakpoint, then keep going. */
2924 tss
->stepping_over_breakpoint
= 1;
2930 case BPSTAT_WHAT_LAST
:
2931 /* Not a real code, but listed here to shut up gcc -Wall. */
2933 case BPSTAT_WHAT_KEEP_CHECKING
:
2938 /* We come here if we hit a breakpoint but should not
2939 stop for it. Possibly we also were stepping
2940 and should stop for that. So fall through and
2941 test for stepping. But, if not stepping,
2944 /* Are we stepping to get the inferior out of the dynamic linker's
2945 hook (and possibly the dld itself) after catching a shlib
2947 if (tss
->stepping_through_solib_after_catch
)
2949 #if defined(SOLIB_ADD)
2950 /* Have we reached our destination? If not, keep going. */
2951 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
2954 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
2955 tss
->stepping_over_breakpoint
= 1;
2961 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
2962 /* Else, stop and report the catchpoint(s) whose triggering
2963 caused us to begin stepping. */
2964 tss
->stepping_through_solib_after_catch
= 0;
2965 bpstat_clear (&stop_bpstat
);
2966 stop_bpstat
= bpstat_copy (tss
->stepping_through_solib_catchpoints
);
2967 bpstat_clear (&tss
->stepping_through_solib_catchpoints
);
2968 stop_print_frame
= 1;
2969 stop_stepping (ecs
);
2973 if (step_resume_breakpoint
)
2976 fprintf_unfiltered (gdb_stdlog
,
2977 "infrun: step-resume breakpoint is inserted\n");
2979 /* Having a step-resume breakpoint overrides anything
2980 else having to do with stepping commands until
2981 that breakpoint is reached. */
2986 if (step_range_end
== 0)
2989 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
2990 /* Likewise if we aren't even stepping. */
2995 /* If stepping through a line, keep going if still within it.
2997 Note that step_range_end is the address of the first instruction
2998 beyond the step range, and NOT the address of the last instruction
3000 if (stop_pc
>= step_range_start
&& stop_pc
< step_range_end
)
3003 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping inside range [0x%s-0x%s]\n",
3004 paddr_nz (step_range_start
),
3005 paddr_nz (step_range_end
));
3010 /* We stepped out of the stepping range. */
3012 /* If we are stepping at the source level and entered the runtime
3013 loader dynamic symbol resolution code, we keep on single stepping
3014 until we exit the run time loader code and reach the callee's
3016 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3017 && in_solib_dynsym_resolve_code (stop_pc
))
3019 CORE_ADDR pc_after_resolver
=
3020 gdbarch_skip_solib_resolver (current_gdbarch
, stop_pc
);
3023 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
3025 if (pc_after_resolver
)
3027 /* Set up a step-resume breakpoint at the address
3028 indicated by SKIP_SOLIB_RESOLVER. */
3029 struct symtab_and_line sr_sal
;
3031 sr_sal
.pc
= pc_after_resolver
;
3033 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3040 if (step_range_end
!= 1
3041 && (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3042 || step_over_calls
== STEP_OVER_ALL
)
3043 && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME
)
3046 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
3047 /* The inferior, while doing a "step" or "next", has ended up in
3048 a signal trampoline (either by a signal being delivered or by
3049 the signal handler returning). Just single-step until the
3050 inferior leaves the trampoline (either by calling the handler
3056 /* Check for subroutine calls. The check for the current frame
3057 equalling the step ID is not necessary - the check of the
3058 previous frame's ID is sufficient - but it is a common case and
3059 cheaper than checking the previous frame's ID.
3061 NOTE: frame_id_eq will never report two invalid frame IDs as
3062 being equal, so to get into this block, both the current and
3063 previous frame must have valid frame IDs. */
3064 if (!frame_id_eq (get_frame_id (get_current_frame ()), step_frame_id
)
3065 && frame_id_eq (frame_unwind_id (get_current_frame ()), step_frame_id
))
3067 CORE_ADDR real_stop_pc
;
3070 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
3072 if ((step_over_calls
== STEP_OVER_NONE
)
3073 || ((step_range_end
== 1)
3074 && in_prologue (prev_pc
, ecs
->stop_func_start
)))
3076 /* I presume that step_over_calls is only 0 when we're
3077 supposed to be stepping at the assembly language level
3078 ("stepi"). Just stop. */
3079 /* Also, maybe we just did a "nexti" inside a prolog, so we
3080 thought it was a subroutine call but it was not. Stop as
3083 print_stop_reason (END_STEPPING_RANGE
, 0);
3084 stop_stepping (ecs
);
3088 if (step_over_calls
== STEP_OVER_ALL
)
3090 /* We're doing a "next", set a breakpoint at callee's return
3091 address (the address at which the caller will
3093 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3098 /* If we are in a function call trampoline (a stub between the
3099 calling routine and the real function), locate the real
3100 function. That's what tells us (a) whether we want to step
3101 into it at all, and (b) what prologue we want to run to the
3102 end of, if we do step into it. */
3103 real_stop_pc
= skip_language_trampoline (get_current_frame (), stop_pc
);
3104 if (real_stop_pc
== 0)
3105 real_stop_pc
= gdbarch_skip_trampoline_code
3106 (current_gdbarch
, get_current_frame (), stop_pc
);
3107 if (real_stop_pc
!= 0)
3108 ecs
->stop_func_start
= real_stop_pc
;
3110 if (in_solib_dynsym_resolve_code (ecs
->stop_func_start
))
3112 struct symtab_and_line sr_sal
;
3114 sr_sal
.pc
= ecs
->stop_func_start
;
3116 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3121 /* If we have line number information for the function we are
3122 thinking of stepping into, step into it.
3124 If there are several symtabs at that PC (e.g. with include
3125 files), just want to know whether *any* of them have line
3126 numbers. find_pc_line handles this. */
3128 struct symtab_and_line tmp_sal
;
3130 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3131 if (tmp_sal
.line
!= 0)
3133 step_into_function (ecs
);
3138 /* If we have no line number and the step-stop-if-no-debug is
3139 set, we stop the step so that the user has a chance to switch
3140 in assembly mode. */
3141 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
&& step_stop_if_no_debug
)
3144 print_stop_reason (END_STEPPING_RANGE
, 0);
3145 stop_stepping (ecs
);
3149 /* Set a breakpoint at callee's return address (the address at
3150 which the caller will resume). */
3151 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3156 /* If we're in the return path from a shared library trampoline,
3157 we want to proceed through the trampoline when stepping. */
3158 if (gdbarch_in_solib_return_trampoline (current_gdbarch
,
3159 stop_pc
, ecs
->stop_func_name
))
3161 /* Determine where this trampoline returns. */
3162 CORE_ADDR real_stop_pc
;
3163 real_stop_pc
= gdbarch_skip_trampoline_code
3164 (current_gdbarch
, get_current_frame (), stop_pc
);
3167 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
3169 /* Only proceed through if we know where it's going. */
3172 /* And put the step-breakpoint there and go until there. */
3173 struct symtab_and_line sr_sal
;
3175 init_sal (&sr_sal
); /* initialize to zeroes */
3176 sr_sal
.pc
= real_stop_pc
;
3177 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3179 /* Do not specify what the fp should be when we stop since
3180 on some machines the prologue is where the new fp value
3182 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3184 /* Restart without fiddling with the step ranges or
3191 stop_pc_sal
= find_pc_line (stop_pc
, 0);
3193 /* NOTE: tausq/2004-05-24: This if block used to be done before all
3194 the trampoline processing logic, however, there are some trampolines
3195 that have no names, so we should do trampoline handling first. */
3196 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3197 && ecs
->stop_func_name
== NULL
3198 && stop_pc_sal
.line
== 0)
3201 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
3203 /* The inferior just stepped into, or returned to, an
3204 undebuggable function (where there is no debugging information
3205 and no line number corresponding to the address where the
3206 inferior stopped). Since we want to skip this kind of code,
3207 we keep going until the inferior returns from this
3208 function - unless the user has asked us not to (via
3209 set step-mode) or we no longer know how to get back
3210 to the call site. */
3211 if (step_stop_if_no_debug
3212 || !frame_id_p (frame_unwind_id (get_current_frame ())))
3214 /* If we have no line number and the step-stop-if-no-debug
3215 is set, we stop the step so that the user has a chance to
3216 switch in assembly mode. */
3218 print_stop_reason (END_STEPPING_RANGE
, 0);
3219 stop_stepping (ecs
);
3224 /* Set a breakpoint at callee's return address (the address
3225 at which the caller will resume). */
3226 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3232 if (step_range_end
== 1)
3234 /* It is stepi or nexti. We always want to stop stepping after
3237 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
3239 print_stop_reason (END_STEPPING_RANGE
, 0);
3240 stop_stepping (ecs
);
3244 if (stop_pc_sal
.line
== 0)
3246 /* We have no line number information. That means to stop
3247 stepping (does this always happen right after one instruction,
3248 when we do "s" in a function with no line numbers,
3249 or can this happen as a result of a return or longjmp?). */
3251 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
3253 print_stop_reason (END_STEPPING_RANGE
, 0);
3254 stop_stepping (ecs
);
3258 if ((stop_pc
== stop_pc_sal
.pc
)
3259 && (tss
->current_line
!= stop_pc_sal
.line
3260 || tss
->current_symtab
!= stop_pc_sal
.symtab
))
3262 /* We are at the start of a different line. So stop. Note that
3263 we don't stop if we step into the middle of a different line.
3264 That is said to make things like for (;;) statements work
3267 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
3269 print_stop_reason (END_STEPPING_RANGE
, 0);
3270 stop_stepping (ecs
);
3274 /* We aren't done stepping.
3276 Optimize by setting the stepping range to the line.
3277 (We might not be in the original line, but if we entered a
3278 new line in mid-statement, we continue stepping. This makes
3279 things like for(;;) statements work better.) */
3281 step_range_start
= stop_pc_sal
.pc
;
3282 step_range_end
= stop_pc_sal
.end
;
3283 step_frame_id
= get_frame_id (get_current_frame ());
3284 tss
->current_line
= stop_pc_sal
.line
;
3285 tss
->current_symtab
= stop_pc_sal
.symtab
;
3287 /* In the case where we just stepped out of a function into the
3288 middle of a line of the caller, continue stepping, but
3289 step_frame_id must be modified to current frame */
3291 /* NOTE: cagney/2003-10-16: I think this frame ID inner test is too
3292 generous. It will trigger on things like a step into a frameless
3293 stackless leaf function. I think the logic should instead look
3294 at the unwound frame ID has that should give a more robust
3295 indication of what happened. */
3296 if (step
- ID
== current
- ID
)
3297 still stepping in same function
;
3298 else if (step
- ID
== unwind (current
- ID
))
3299 stepped into a function
;
3301 stepped out of a function
;
3302 /* Of course this assumes that the frame ID unwind code is robust
3303 and we're willing to introduce frame unwind logic into this
3304 function. Fortunately, those days are nearly upon us. */
3307 struct frame_info
*frame
= get_current_frame ();
3308 struct frame_id current_frame
= get_frame_id (frame
);
3309 if (!(frame_id_inner (get_frame_arch (frame
), current_frame
,
3311 step_frame_id
= current_frame
;
3315 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
3319 /* Are we in the middle of stepping? */
3322 currently_stepping (struct thread_stepping_state
*tss
)
3324 return (((step_range_end
&& step_resume_breakpoint
== NULL
)
3325 || stepping_over_breakpoint
)
3326 || tss
->stepping_through_solib_after_catch
3327 || bpstat_should_step ());
3330 /* Subroutine call with source code we should not step over. Do step
3331 to the first line of code in it. */
3334 step_into_function (struct execution_control_state
*ecs
)
3337 struct symtab_and_line stop_func_sal
, sr_sal
;
3339 s
= find_pc_symtab (stop_pc
);
3340 if (s
&& s
->language
!= language_asm
)
3341 ecs
->stop_func_start
= gdbarch_skip_prologue
3342 (current_gdbarch
, ecs
->stop_func_start
);
3344 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3345 /* Use the step_resume_break to step until the end of the prologue,
3346 even if that involves jumps (as it seems to on the vax under
3348 /* If the prologue ends in the middle of a source line, continue to
3349 the end of that source line (if it is still within the function).
3350 Otherwise, just go to end of prologue. */
3351 if (stop_func_sal
.end
3352 && stop_func_sal
.pc
!= ecs
->stop_func_start
3353 && stop_func_sal
.end
< ecs
->stop_func_end
)
3354 ecs
->stop_func_start
= stop_func_sal
.end
;
3356 /* Architectures which require breakpoint adjustment might not be able
3357 to place a breakpoint at the computed address. If so, the test
3358 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
3359 ecs->stop_func_start to an address at which a breakpoint may be
3360 legitimately placed.
3362 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
3363 made, GDB will enter an infinite loop when stepping through
3364 optimized code consisting of VLIW instructions which contain
3365 subinstructions corresponding to different source lines. On
3366 FR-V, it's not permitted to place a breakpoint on any but the
3367 first subinstruction of a VLIW instruction. When a breakpoint is
3368 set, GDB will adjust the breakpoint address to the beginning of
3369 the VLIW instruction. Thus, we need to make the corresponding
3370 adjustment here when computing the stop address. */
3372 if (gdbarch_adjust_breakpoint_address_p (current_gdbarch
))
3374 ecs
->stop_func_start
3375 = gdbarch_adjust_breakpoint_address (current_gdbarch
,
3376 ecs
->stop_func_start
);
3379 if (ecs
->stop_func_start
== stop_pc
)
3381 /* We are already there: stop now. */
3383 print_stop_reason (END_STEPPING_RANGE
, 0);
3384 stop_stepping (ecs
);
3389 /* Put the step-breakpoint there and go until there. */
3390 init_sal (&sr_sal
); /* initialize to zeroes */
3391 sr_sal
.pc
= ecs
->stop_func_start
;
3392 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
3394 /* Do not specify what the fp should be when we stop since on
3395 some machines the prologue is where the new fp value is
3397 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3399 /* And make sure stepping stops right away then. */
3400 step_range_end
= step_range_start
;
3405 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
3406 This is used to both functions and to skip over code. */
3409 insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
3410 struct frame_id sr_id
)
3412 /* There should never be more than one step-resume or longjmp-resume
3413 breakpoint per thread, so we should never be setting a new
3414 step_resume_breakpoint when one is already active. */
3415 gdb_assert (step_resume_breakpoint
== NULL
);
3418 fprintf_unfiltered (gdb_stdlog
,
3419 "infrun: inserting step-resume breakpoint at 0x%s\n",
3420 paddr_nz (sr_sal
.pc
));
3422 step_resume_breakpoint
= set_momentary_breakpoint (sr_sal
, sr_id
,
3426 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
3427 to skip a potential signal handler.
3429 This is called with the interrupted function's frame. The signal
3430 handler, when it returns, will resume the interrupted function at
3434 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
3436 struct symtab_and_line sr_sal
;
3438 gdb_assert (return_frame
!= NULL
);
3439 init_sal (&sr_sal
); /* initialize to zeros */
3441 sr_sal
.pc
= gdbarch_addr_bits_remove
3442 (current_gdbarch
, get_frame_pc (return_frame
));
3443 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3445 insert_step_resume_breakpoint_at_sal (sr_sal
, get_frame_id (return_frame
));
3448 /* Similar to insert_step_resume_breakpoint_at_frame, except
3449 but a breakpoint at the previous frame's PC. This is used to
3450 skip a function after stepping into it (for "next" or if the called
3451 function has no debugging information).
3453 The current function has almost always been reached by single
3454 stepping a call or return instruction. NEXT_FRAME belongs to the
3455 current function, and the breakpoint will be set at the caller's
3458 This is a separate function rather than reusing
3459 insert_step_resume_breakpoint_at_frame in order to avoid
3460 get_prev_frame, which may stop prematurely (see the implementation
3461 of frame_unwind_id for an example). */
3464 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
3466 struct symtab_and_line sr_sal
;
3468 /* We shouldn't have gotten here if we don't know where the call site
3470 gdb_assert (frame_id_p (frame_unwind_id (next_frame
)));
3472 init_sal (&sr_sal
); /* initialize to zeros */
3474 sr_sal
.pc
= gdbarch_addr_bits_remove
3475 (current_gdbarch
, frame_pc_unwind (next_frame
));
3476 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3478 insert_step_resume_breakpoint_at_sal (sr_sal
, frame_unwind_id (next_frame
));
3481 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
3482 new breakpoint at the target of a jmp_buf. The handling of
3483 longjmp-resume uses the same mechanisms used for handling
3484 "step-resume" breakpoints. */
3487 insert_longjmp_resume_breakpoint (CORE_ADDR pc
)
3489 /* There should never be more than one step-resume or longjmp-resume
3490 breakpoint per thread, so we should never be setting a new
3491 longjmp_resume_breakpoint when one is already active. */
3492 gdb_assert (step_resume_breakpoint
== NULL
);
3495 fprintf_unfiltered (gdb_stdlog
,
3496 "infrun: inserting longjmp-resume breakpoint at 0x%s\n",
3499 step_resume_breakpoint
=
3500 set_momentary_breakpoint_at_pc (pc
, bp_longjmp_resume
);
3504 stop_stepping (struct execution_control_state
*ecs
)
3507 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
3509 /* Let callers know we don't want to wait for the inferior anymore. */
3510 ecs
->wait_some_more
= 0;
3513 /* This function handles various cases where we need to continue
3514 waiting for the inferior. */
3515 /* (Used to be the keep_going: label in the old wait_for_inferior) */
3518 keep_going (struct execution_control_state
*ecs
)
3520 /* Save the pc before execution, to compare with pc after stop. */
3521 prev_pc
= read_pc (); /* Might have been DECR_AFTER_BREAK */
3523 /* If we did not do break;, it means we should keep running the
3524 inferior and not return to debugger. */
3526 if (stepping_over_breakpoint
&& stop_signal
!= TARGET_SIGNAL_TRAP
)
3528 /* We took a signal (which we are supposed to pass through to
3529 the inferior, else we'd have done a break above) and we
3530 haven't yet gotten our trap. Simply continue. */
3531 resume (currently_stepping (tss
), stop_signal
);
3535 /* Either the trap was not expected, but we are continuing
3536 anyway (the user asked that this signal be passed to the
3539 The signal was SIGTRAP, e.g. it was our signal, but we
3540 decided we should resume from it.
3542 We're going to run this baby now!
3544 Note that insert_breakpoints won't try to re-insert
3545 already inserted breakpoints. Therefore, we don't
3546 care if breakpoints were already inserted, or not. */
3548 if (tss
->stepping_over_breakpoint
)
3550 if (! use_displaced_stepping (current_gdbarch
))
3551 /* Since we can't do a displaced step, we have to remove
3552 the breakpoint while we step it. To keep things
3553 simple, we remove them all. */
3554 remove_breakpoints ();
3558 struct gdb_exception e
;
3559 /* Stop stepping when inserting breakpoints
3561 TRY_CATCH (e
, RETURN_MASK_ERROR
)
3563 insert_breakpoints ();
3567 stop_stepping (ecs
);
3572 stepping_over_breakpoint
= tss
->stepping_over_breakpoint
;
3574 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3575 specifies that such a signal should be delivered to the
3578 Typically, this would occure when a user is debugging a
3579 target monitor on a simulator: the target monitor sets a
3580 breakpoint; the simulator encounters this break-point and
3581 halts the simulation handing control to GDB; GDB, noteing
3582 that the break-point isn't valid, returns control back to the
3583 simulator; the simulator then delivers the hardware
3584 equivalent of a SIGNAL_TRAP to the program being debugged. */
3586 if (stop_signal
== TARGET_SIGNAL_TRAP
&& !signal_program
[stop_signal
])
3587 stop_signal
= TARGET_SIGNAL_0
;
3590 resume (currently_stepping (tss
), stop_signal
);
3593 prepare_to_wait (ecs
);
3596 /* This function normally comes after a resume, before
3597 handle_inferior_event exits. It takes care of any last bits of
3598 housekeeping, and sets the all-important wait_some_more flag. */
3601 prepare_to_wait (struct execution_control_state
*ecs
)
3604 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
3605 if (infwait_state
== infwait_normal_state
)
3607 overlay_cache_invalid
= 1;
3609 /* We have to invalidate the registers BEFORE calling
3610 target_wait because they can be loaded from the target while
3611 in target_wait. This makes remote debugging a bit more
3612 efficient for those targets that provide critical registers
3613 as part of their normal status mechanism. */
3615 registers_changed ();
3616 waiton_ptid
= pid_to_ptid (-1);
3618 /* This is the old end of the while loop. Let everybody know we
3619 want to wait for the inferior some more and get called again
3621 ecs
->wait_some_more
= 1;
3624 /* Print why the inferior has stopped. We always print something when
3625 the inferior exits, or receives a signal. The rest of the cases are
3626 dealt with later on in normal_stop() and print_it_typical(). Ideally
3627 there should be a call to this function from handle_inferior_event()
3628 each time stop_stepping() is called.*/
3630 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
3632 switch (stop_reason
)
3634 case END_STEPPING_RANGE
:
3635 /* We are done with a step/next/si/ni command. */
3636 /* For now print nothing. */
3637 /* Print a message only if not in the middle of doing a "step n"
3638 operation for n > 1 */
3639 if (!step_multi
|| !stop_step
)
3640 if (ui_out_is_mi_like_p (uiout
))
3643 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
3646 /* The inferior was terminated by a signal. */
3647 annotate_signalled ();
3648 if (ui_out_is_mi_like_p (uiout
))
3651 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
3652 ui_out_text (uiout
, "\nProgram terminated with signal ");
3653 annotate_signal_name ();
3654 ui_out_field_string (uiout
, "signal-name",
3655 target_signal_to_name (stop_info
));
3656 annotate_signal_name_end ();
3657 ui_out_text (uiout
, ", ");
3658 annotate_signal_string ();
3659 ui_out_field_string (uiout
, "signal-meaning",
3660 target_signal_to_string (stop_info
));
3661 annotate_signal_string_end ();
3662 ui_out_text (uiout
, ".\n");
3663 ui_out_text (uiout
, "The program no longer exists.\n");
3666 /* The inferior program is finished. */
3667 annotate_exited (stop_info
);
3670 if (ui_out_is_mi_like_p (uiout
))
3671 ui_out_field_string (uiout
, "reason",
3672 async_reason_lookup (EXEC_ASYNC_EXITED
));
3673 ui_out_text (uiout
, "\nProgram exited with code ");
3674 ui_out_field_fmt (uiout
, "exit-code", "0%o",
3675 (unsigned int) stop_info
);
3676 ui_out_text (uiout
, ".\n");
3680 if (ui_out_is_mi_like_p (uiout
))
3683 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
3684 ui_out_text (uiout
, "\nProgram exited normally.\n");
3686 /* Support the --return-child-result option. */
3687 return_child_result_value
= stop_info
;
3689 case SIGNAL_RECEIVED
:
3690 /* Signal received. The signal table tells us to print about
3693 ui_out_text (uiout
, "\nProgram received signal ");
3694 annotate_signal_name ();
3695 if (ui_out_is_mi_like_p (uiout
))
3697 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
3698 ui_out_field_string (uiout
, "signal-name",
3699 target_signal_to_name (stop_info
));
3700 annotate_signal_name_end ();
3701 ui_out_text (uiout
, ", ");
3702 annotate_signal_string ();
3703 ui_out_field_string (uiout
, "signal-meaning",
3704 target_signal_to_string (stop_info
));
3705 annotate_signal_string_end ();
3706 ui_out_text (uiout
, ".\n");
3709 internal_error (__FILE__
, __LINE__
,
3710 _("print_stop_reason: unrecognized enum value"));
3716 /* Here to return control to GDB when the inferior stops for real.
3717 Print appropriate messages, remove breakpoints, give terminal our modes.
3719 STOP_PRINT_FRAME nonzero means print the executing frame
3720 (pc, function, args, file, line number and line text).
3721 BREAKPOINTS_FAILED nonzero means stop was due to error
3722 attempting to insert breakpoints. */
3727 struct target_waitstatus last
;
3730 get_last_target_status (&last_ptid
, &last
);
3732 /* In non-stop mode, we don't want GDB to switch threads behind the
3733 user's back, to avoid races where the user is typing a command to
3734 apply to thread x, but GDB switches to thread y before the user
3735 finishes entering the command. */
3737 /* As with the notification of thread events, we want to delay
3738 notifying the user that we've switched thread context until
3739 the inferior actually stops.
3741 There's no point in saying anything if the inferior has exited.
3742 Note that SIGNALLED here means "exited with a signal", not
3743 "received a signal". */
3745 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
3746 && target_has_execution
3747 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3748 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3750 target_terminal_ours_for_output ();
3751 printf_filtered (_("[Switching to %s]\n"),
3752 target_pid_to_str (inferior_ptid
));
3753 annotate_thread_changed ();
3754 previous_inferior_ptid
= inferior_ptid
;
3757 /* NOTE drow/2004-01-17: Is this still necessary? */
3758 /* Make sure that the current_frame's pc is correct. This
3759 is a correction for setting up the frame info before doing
3760 gdbarch_decr_pc_after_break */
3761 if (target_has_execution
)
3762 /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
3763 gdbarch_decr_pc_after_break, the program counter can change. Ask the
3764 frame code to check for this and sort out any resultant mess.
3765 gdbarch_decr_pc_after_break needs to just go away. */
3766 deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
3768 if (!breakpoints_always_inserted_mode () && target_has_execution
)
3770 if (remove_breakpoints ())
3772 target_terminal_ours_for_output ();
3773 printf_filtered (_("\
3774 Cannot remove breakpoints because program is no longer writable.\n\
3775 It might be running in another process.\n\
3776 Further execution is probably impossible.\n"));
3780 /* If an auto-display called a function and that got a signal,
3781 delete that auto-display to avoid an infinite recursion. */
3783 if (stopped_by_random_signal
)
3784 disable_current_display ();
3786 /* Don't print a message if in the middle of doing a "step n"
3787 operation for n > 1 */
3788 if (step_multi
&& stop_step
)
3791 target_terminal_ours ();
3793 /* Set the current source location. This will also happen if we
3794 display the frame below, but the current SAL will be incorrect
3795 during a user hook-stop function. */
3796 if (target_has_stack
&& !stop_stack_dummy
)
3797 set_current_sal_from_frame (get_current_frame (), 1);
3799 /* Look up the hook_stop and run it (CLI internally handles problem
3800 of stop_command's pre-hook not existing). */
3802 catch_errors (hook_stop_stub
, stop_command
,
3803 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
3805 if (!target_has_stack
)
3811 /* Select innermost stack frame - i.e., current frame is frame 0,
3812 and current location is based on that.
3813 Don't do this on return from a stack dummy routine,
3814 or if the program has exited. */
3816 if (!stop_stack_dummy
)
3818 select_frame (get_current_frame ());
3820 /* Print current location without a level number, if
3821 we have changed functions or hit a breakpoint.
3822 Print source line if we have one.
3823 bpstat_print() contains the logic deciding in detail
3824 what to print, based on the event(s) that just occurred. */
3826 /* If --batch-silent is enabled then there's no need to print the current
3827 source location, and to try risks causing an error message about
3828 missing source files. */
3829 if (stop_print_frame
&& !batch_silent
)
3833 int do_frame_printing
= 1;
3835 bpstat_ret
= bpstat_print (stop_bpstat
);
3839 /* If we had hit a shared library event breakpoint,
3840 bpstat_print would print out this message. If we hit
3841 an OS-level shared library event, do the same
3843 if (last
.kind
== TARGET_WAITKIND_LOADED
)
3845 printf_filtered (_("Stopped due to shared library event\n"));
3846 source_flag
= SRC_LINE
; /* something bogus */
3847 do_frame_printing
= 0;
3851 /* FIXME: cagney/2002-12-01: Given that a frame ID does
3852 (or should) carry around the function and does (or
3853 should) use that when doing a frame comparison. */
3855 && frame_id_eq (step_frame_id
,
3856 get_frame_id (get_current_frame ()))
3857 && step_start_function
== find_pc_function (stop_pc
))
3858 source_flag
= SRC_LINE
; /* finished step, just print source line */
3860 source_flag
= SRC_AND_LOC
; /* print location and source line */
3862 case PRINT_SRC_AND_LOC
:
3863 source_flag
= SRC_AND_LOC
; /* print location and source line */
3865 case PRINT_SRC_ONLY
:
3866 source_flag
= SRC_LINE
;
3869 source_flag
= SRC_LINE
; /* something bogus */
3870 do_frame_printing
= 0;
3873 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
3876 if (ui_out_is_mi_like_p (uiout
))
3879 ui_out_field_int (uiout
, "thread-id",
3880 pid_to_thread_id (inferior_ptid
));
3883 struct cleanup
*back_to
= make_cleanup_ui_out_list_begin_end
3884 (uiout
, "stopped-threads");
3885 ui_out_field_int (uiout
, NULL
,
3886 pid_to_thread_id (inferior_ptid
));
3887 do_cleanups (back_to
);
3890 ui_out_field_string (uiout
, "stopped-threads", "all");
3892 /* The behavior of this routine with respect to the source
3894 SRC_LINE: Print only source line
3895 LOCATION: Print only location
3896 SRC_AND_LOC: Print location and source line */
3897 if (do_frame_printing
)
3898 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
3900 /* Display the auto-display expressions. */
3905 /* Save the function value return registers, if we care.
3906 We might be about to restore their previous contents. */
3907 if (proceed_to_finish
)
3909 /* This should not be necessary. */
3911 regcache_xfree (stop_registers
);
3913 /* NB: The copy goes through to the target picking up the value of
3914 all the registers. */
3915 stop_registers
= regcache_dup (get_current_regcache ());
3918 if (stop_stack_dummy
)
3920 /* Pop the empty frame that contains the stack dummy. POP_FRAME
3921 ends with a setting of the current frame, so we can use that
3923 frame_pop (get_current_frame ());
3924 /* Set stop_pc to what it was before we called the function.
3925 Can't rely on restore_inferior_status because that only gets
3926 called if we don't stop in the called function. */
3927 stop_pc
= read_pc ();
3928 select_frame (get_current_frame ());
3932 annotate_stopped ();
3933 if (!suppress_stop_observer
&& !step_multi
)
3934 observer_notify_normal_stop (stop_bpstat
);
3935 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3936 Delete any breakpoint that is to be deleted at the next stop. */
3937 breakpoint_auto_delete (stop_bpstat
);
3939 if (target_has_execution
3940 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3941 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3944 set_running (pid_to_ptid (-1), 0);
3946 set_running (inferior_ptid
, 0);
3951 hook_stop_stub (void *cmd
)
3953 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
3958 signal_stop_state (int signo
)
3960 /* Always stop on signals if we're just gaining control of the
3962 return signal_stop
[signo
] || stop_soon
!= NO_STOP_QUIETLY
;
3966 signal_print_state (int signo
)
3968 return signal_print
[signo
];
3972 signal_pass_state (int signo
)
3974 return signal_program
[signo
];
3978 signal_stop_update (int signo
, int state
)
3980 int ret
= signal_stop
[signo
];
3981 signal_stop
[signo
] = state
;
3986 signal_print_update (int signo
, int state
)
3988 int ret
= signal_print
[signo
];
3989 signal_print
[signo
] = state
;
3994 signal_pass_update (int signo
, int state
)
3996 int ret
= signal_program
[signo
];
3997 signal_program
[signo
] = state
;
4002 sig_print_header (void)
4004 printf_filtered (_("\
4005 Signal Stop\tPrint\tPass to program\tDescription\n"));
4009 sig_print_info (enum target_signal oursig
)
4011 char *name
= target_signal_to_name (oursig
);
4012 int name_padding
= 13 - strlen (name
);
4014 if (name_padding
<= 0)
4017 printf_filtered ("%s", name
);
4018 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
4019 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
4020 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
4021 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
4022 printf_filtered ("%s\n", target_signal_to_string (oursig
));
4025 /* Specify how various signals in the inferior should be handled. */
4028 handle_command (char *args
, int from_tty
)
4031 int digits
, wordlen
;
4032 int sigfirst
, signum
, siglast
;
4033 enum target_signal oursig
;
4036 unsigned char *sigs
;
4037 struct cleanup
*old_chain
;
4041 error_no_arg (_("signal to handle"));
4044 /* Allocate and zero an array of flags for which signals to handle. */
4046 nsigs
= (int) TARGET_SIGNAL_LAST
;
4047 sigs
= (unsigned char *) alloca (nsigs
);
4048 memset (sigs
, 0, nsigs
);
4050 /* Break the command line up into args. */
4052 argv
= buildargv (args
);
4057 old_chain
= make_cleanup_freeargv (argv
);
4059 /* Walk through the args, looking for signal oursigs, signal names, and
4060 actions. Signal numbers and signal names may be interspersed with
4061 actions, with the actions being performed for all signals cumulatively
4062 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
4064 while (*argv
!= NULL
)
4066 wordlen
= strlen (*argv
);
4067 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
4071 sigfirst
= siglast
= -1;
4073 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
4075 /* Apply action to all signals except those used by the
4076 debugger. Silently skip those. */
4079 siglast
= nsigs
- 1;
4081 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
4083 SET_SIGS (nsigs
, sigs
, signal_stop
);
4084 SET_SIGS (nsigs
, sigs
, signal_print
);
4086 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
4088 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4090 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
4092 SET_SIGS (nsigs
, sigs
, signal_print
);
4094 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
4096 SET_SIGS (nsigs
, sigs
, signal_program
);
4098 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
4100 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4102 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
4104 SET_SIGS (nsigs
, sigs
, signal_program
);
4106 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
4108 UNSET_SIGS (nsigs
, sigs
, signal_print
);
4109 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4111 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
4113 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4115 else if (digits
> 0)
4117 /* It is numeric. The numeric signal refers to our own
4118 internal signal numbering from target.h, not to host/target
4119 signal number. This is a feature; users really should be
4120 using symbolic names anyway, and the common ones like
4121 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
4123 sigfirst
= siglast
= (int)
4124 target_signal_from_command (atoi (*argv
));
4125 if ((*argv
)[digits
] == '-')
4128 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
4130 if (sigfirst
> siglast
)
4132 /* Bet he didn't figure we'd think of this case... */
4140 oursig
= target_signal_from_name (*argv
);
4141 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
4143 sigfirst
= siglast
= (int) oursig
;
4147 /* Not a number and not a recognized flag word => complain. */
4148 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
4152 /* If any signal numbers or symbol names were found, set flags for
4153 which signals to apply actions to. */
4155 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
4157 switch ((enum target_signal
) signum
)
4159 case TARGET_SIGNAL_TRAP
:
4160 case TARGET_SIGNAL_INT
:
4161 if (!allsigs
&& !sigs
[signum
])
4163 if (query ("%s is used by the debugger.\n\
4164 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal
) signum
)))
4170 printf_unfiltered (_("Not confirmed, unchanged.\n"));
4171 gdb_flush (gdb_stdout
);
4175 case TARGET_SIGNAL_0
:
4176 case TARGET_SIGNAL_DEFAULT
:
4177 case TARGET_SIGNAL_UNKNOWN
:
4178 /* Make sure that "all" doesn't print these. */
4189 target_notice_signals (inferior_ptid
);
4193 /* Show the results. */
4194 sig_print_header ();
4195 for (signum
= 0; signum
< nsigs
; signum
++)
4199 sig_print_info (signum
);
4204 do_cleanups (old_chain
);
4208 xdb_handle_command (char *args
, int from_tty
)
4211 struct cleanup
*old_chain
;
4213 /* Break the command line up into args. */
4215 argv
= buildargv (args
);
4220 old_chain
= make_cleanup_freeargv (argv
);
4221 if (argv
[1] != (char *) NULL
)
4226 bufLen
= strlen (argv
[0]) + 20;
4227 argBuf
= (char *) xmalloc (bufLen
);
4231 enum target_signal oursig
;
4233 oursig
= target_signal_from_name (argv
[0]);
4234 memset (argBuf
, 0, bufLen
);
4235 if (strcmp (argv
[1], "Q") == 0)
4236 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4239 if (strcmp (argv
[1], "s") == 0)
4241 if (!signal_stop
[oursig
])
4242 sprintf (argBuf
, "%s %s", argv
[0], "stop");
4244 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
4246 else if (strcmp (argv
[1], "i") == 0)
4248 if (!signal_program
[oursig
])
4249 sprintf (argBuf
, "%s %s", argv
[0], "pass");
4251 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
4253 else if (strcmp (argv
[1], "r") == 0)
4255 if (!signal_print
[oursig
])
4256 sprintf (argBuf
, "%s %s", argv
[0], "print");
4258 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4264 handle_command (argBuf
, from_tty
);
4266 printf_filtered (_("Invalid signal handling flag.\n"));
4271 do_cleanups (old_chain
);
4274 /* Print current contents of the tables set by the handle command.
4275 It is possible we should just be printing signals actually used
4276 by the current target (but for things to work right when switching
4277 targets, all signals should be in the signal tables). */
4280 signals_info (char *signum_exp
, int from_tty
)
4282 enum target_signal oursig
;
4283 sig_print_header ();
4287 /* First see if this is a symbol name. */
4288 oursig
= target_signal_from_name (signum_exp
);
4289 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
4291 /* No, try numeric. */
4293 target_signal_from_command (parse_and_eval_long (signum_exp
));
4295 sig_print_info (oursig
);
4299 printf_filtered ("\n");
4300 /* These ugly casts brought to you by the native VAX compiler. */
4301 for (oursig
= TARGET_SIGNAL_FIRST
;
4302 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
4303 oursig
= (enum target_signal
) ((int) oursig
+ 1))
4307 if (oursig
!= TARGET_SIGNAL_UNKNOWN
4308 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
4309 sig_print_info (oursig
);
4312 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
4315 struct inferior_status
4317 enum target_signal stop_signal
;
4321 int stop_stack_dummy
;
4322 int stopped_by_random_signal
;
4323 int stepping_over_breakpoint
;
4324 CORE_ADDR step_range_start
;
4325 CORE_ADDR step_range_end
;
4326 struct frame_id step_frame_id
;
4327 enum step_over_calls_kind step_over_calls
;
4328 CORE_ADDR step_resume_break_address
;
4329 int stop_after_trap
;
4332 /* These are here because if call_function_by_hand has written some
4333 registers and then decides to call error(), we better not have changed
4335 struct regcache
*registers
;
4337 /* A frame unique identifier. */
4338 struct frame_id selected_frame_id
;
4340 int breakpoint_proceeded
;
4341 int restore_stack_info
;
4342 int proceed_to_finish
;
4346 write_inferior_status_register (struct inferior_status
*inf_status
, int regno
,
4349 int size
= register_size (current_gdbarch
, regno
);
4350 void *buf
= alloca (size
);
4351 store_signed_integer (buf
, size
, val
);
4352 regcache_raw_write (inf_status
->registers
, regno
, buf
);
4355 /* Save all of the information associated with the inferior<==>gdb
4356 connection. INF_STATUS is a pointer to a "struct inferior_status"
4357 (defined in inferior.h). */
4359 struct inferior_status
*
4360 save_inferior_status (int restore_stack_info
)
4362 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
4364 inf_status
->stop_signal
= stop_signal
;
4365 inf_status
->stop_pc
= stop_pc
;
4366 inf_status
->stop_step
= stop_step
;
4367 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
4368 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
4369 inf_status
->stepping_over_breakpoint
= stepping_over_breakpoint
;
4370 inf_status
->step_range_start
= step_range_start
;
4371 inf_status
->step_range_end
= step_range_end
;
4372 inf_status
->step_frame_id
= step_frame_id
;
4373 inf_status
->step_over_calls
= step_over_calls
;
4374 inf_status
->stop_after_trap
= stop_after_trap
;
4375 inf_status
->stop_soon
= stop_soon
;
4376 /* Save original bpstat chain here; replace it with copy of chain.
4377 If caller's caller is walking the chain, they'll be happier if we
4378 hand them back the original chain when restore_inferior_status is
4380 inf_status
->stop_bpstat
= stop_bpstat
;
4381 stop_bpstat
= bpstat_copy (stop_bpstat
);
4382 inf_status
->breakpoint_proceeded
= breakpoint_proceeded
;
4383 inf_status
->restore_stack_info
= restore_stack_info
;
4384 inf_status
->proceed_to_finish
= proceed_to_finish
;
4386 inf_status
->registers
= regcache_dup (get_current_regcache ());
4388 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
4393 restore_selected_frame (void *args
)
4395 struct frame_id
*fid
= (struct frame_id
*) args
;
4396 struct frame_info
*frame
;
4398 frame
= frame_find_by_id (*fid
);
4400 /* If inf_status->selected_frame_id is NULL, there was no previously
4404 warning (_("Unable to restore previously selected frame."));
4408 select_frame (frame
);
4414 restore_inferior_status (struct inferior_status
*inf_status
)
4416 stop_signal
= inf_status
->stop_signal
;
4417 stop_pc
= inf_status
->stop_pc
;
4418 stop_step
= inf_status
->stop_step
;
4419 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
4420 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
4421 stepping_over_breakpoint
= inf_status
->stepping_over_breakpoint
;
4422 step_range_start
= inf_status
->step_range_start
;
4423 step_range_end
= inf_status
->step_range_end
;
4424 step_frame_id
= inf_status
->step_frame_id
;
4425 step_over_calls
= inf_status
->step_over_calls
;
4426 stop_after_trap
= inf_status
->stop_after_trap
;
4427 stop_soon
= inf_status
->stop_soon
;
4428 bpstat_clear (&stop_bpstat
);
4429 stop_bpstat
= inf_status
->stop_bpstat
;
4430 breakpoint_proceeded
= inf_status
->breakpoint_proceeded
;
4431 proceed_to_finish
= inf_status
->proceed_to_finish
;
4433 /* The inferior can be gone if the user types "print exit(0)"
4434 (and perhaps other times). */
4435 if (target_has_execution
)
4436 /* NB: The register write goes through to the target. */
4437 regcache_cpy (get_current_regcache (), inf_status
->registers
);
4438 regcache_xfree (inf_status
->registers
);
4440 /* FIXME: If we are being called after stopping in a function which
4441 is called from gdb, we should not be trying to restore the
4442 selected frame; it just prints a spurious error message (The
4443 message is useful, however, in detecting bugs in gdb (like if gdb
4444 clobbers the stack)). In fact, should we be restoring the
4445 inferior status at all in that case? . */
4447 if (target_has_stack
&& inf_status
->restore_stack_info
)
4449 /* The point of catch_errors is that if the stack is clobbered,
4450 walking the stack might encounter a garbage pointer and
4451 error() trying to dereference it. */
4453 (restore_selected_frame
, &inf_status
->selected_frame_id
,
4454 "Unable to restore previously selected frame:\n",
4455 RETURN_MASK_ERROR
) == 0)
4456 /* Error in restoring the selected frame. Select the innermost
4458 select_frame (get_current_frame ());
4466 do_restore_inferior_status_cleanup (void *sts
)
4468 restore_inferior_status (sts
);
4472 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
4474 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
4478 discard_inferior_status (struct inferior_status
*inf_status
)
4480 /* See save_inferior_status for info on stop_bpstat. */
4481 bpstat_clear (&inf_status
->stop_bpstat
);
4482 regcache_xfree (inf_status
->registers
);
4487 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
4489 struct target_waitstatus last
;
4492 get_last_target_status (&last_ptid
, &last
);
4494 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
4497 if (!ptid_equal (last_ptid
, pid
))
4500 *child_pid
= last
.value
.related_pid
;
4505 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
4507 struct target_waitstatus last
;
4510 get_last_target_status (&last_ptid
, &last
);
4512 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
4515 if (!ptid_equal (last_ptid
, pid
))
4518 *child_pid
= last
.value
.related_pid
;
4523 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
4525 struct target_waitstatus last
;
4528 get_last_target_status (&last_ptid
, &last
);
4530 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
4533 if (!ptid_equal (last_ptid
, pid
))
4536 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
4540 /* Oft used ptids */
4542 ptid_t minus_one_ptid
;
4544 /* Create a ptid given the necessary PID, LWP, and TID components. */
4547 ptid_build (int pid
, long lwp
, long tid
)
4557 /* Create a ptid from just a pid. */
4560 pid_to_ptid (int pid
)
4562 return ptid_build (pid
, 0, 0);
4565 /* Fetch the pid (process id) component from a ptid. */
4568 ptid_get_pid (ptid_t ptid
)
4573 /* Fetch the lwp (lightweight process) component from a ptid. */
4576 ptid_get_lwp (ptid_t ptid
)
4581 /* Fetch the tid (thread id) component from a ptid. */
4584 ptid_get_tid (ptid_t ptid
)
4589 /* ptid_equal() is used to test equality of two ptids. */
4592 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
4594 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
4595 && ptid1
.tid
== ptid2
.tid
);
4598 /* restore_inferior_ptid() will be used by the cleanup machinery
4599 to restore the inferior_ptid value saved in a call to
4600 save_inferior_ptid(). */
4603 restore_inferior_ptid (void *arg
)
4605 ptid_t
*saved_ptid_ptr
= arg
;
4606 inferior_ptid
= *saved_ptid_ptr
;
4610 /* Save the value of inferior_ptid so that it may be restored by a
4611 later call to do_cleanups(). Returns the struct cleanup pointer
4612 needed for later doing the cleanup. */
4615 save_inferior_ptid (void)
4617 ptid_t
*saved_ptid_ptr
;
4619 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
4620 *saved_ptid_ptr
= inferior_ptid
;
4621 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
4626 static int non_stop_1
= 0;
4629 set_non_stop (char *args
, int from_tty
,
4630 struct cmd_list_element
*c
)
4632 if (target_has_execution
)
4634 non_stop_1
= non_stop
;
4635 error (_("Cannot change this setting while the inferior is running."));
4638 non_stop
= non_stop_1
;
4642 show_non_stop (struct ui_file
*file
, int from_tty
,
4643 struct cmd_list_element
*c
, const char *value
)
4645 fprintf_filtered (file
,
4646 _("Controlling the inferior in non-stop mode is %s.\n"),
4652 _initialize_infrun (void)
4656 struct cmd_list_element
*c
;
4658 add_info ("signals", signals_info
, _("\
4659 What debugger does when program gets various signals.\n\
4660 Specify a signal as argument to print info on that signal only."));
4661 add_info_alias ("handle", "signals", 0);
4663 add_com ("handle", class_run
, handle_command
, _("\
4664 Specify how to handle a signal.\n\
4665 Args are signals and actions to apply to those signals.\n\
4666 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4667 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4668 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4669 The special arg \"all\" is recognized to mean all signals except those\n\
4670 used by the debugger, typically SIGTRAP and SIGINT.\n\
4671 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4672 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4673 Stop means reenter debugger if this signal happens (implies print).\n\
4674 Print means print a message if this signal happens.\n\
4675 Pass means let program see this signal; otherwise program doesn't know.\n\
4676 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4677 Pass and Stop may be combined."));
4680 add_com ("lz", class_info
, signals_info
, _("\
4681 What debugger does when program gets various signals.\n\
4682 Specify a signal as argument to print info on that signal only."));
4683 add_com ("z", class_run
, xdb_handle_command
, _("\
4684 Specify how to handle a signal.\n\
4685 Args are signals and actions to apply to those signals.\n\
4686 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4687 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4688 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4689 The special arg \"all\" is recognized to mean all signals except those\n\
4690 used by the debugger, typically SIGTRAP and SIGINT.\n\
4691 Recognized actions include \"s\" (toggles between stop and nostop), \n\
4692 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4693 nopass), \"Q\" (noprint)\n\
4694 Stop means reenter debugger if this signal happens (implies print).\n\
4695 Print means print a message if this signal happens.\n\
4696 Pass means let program see this signal; otherwise program doesn't know.\n\
4697 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4698 Pass and Stop may be combined."));
4702 stop_command
= add_cmd ("stop", class_obscure
,
4703 not_just_help_class_command
, _("\
4704 There is no `stop' command, but you can set a hook on `stop'.\n\
4705 This allows you to set a list of commands to be run each time execution\n\
4706 of the program stops."), &cmdlist
);
4708 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
4709 Set inferior debugging."), _("\
4710 Show inferior debugging."), _("\
4711 When non-zero, inferior specific debugging is enabled."),
4714 &setdebuglist
, &showdebuglist
);
4716 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
4717 Set displaced stepping debugging."), _("\
4718 Show displaced stepping debugging."), _("\
4719 When non-zero, displaced stepping specific debugging is enabled."),
4721 show_debug_displaced
,
4722 &setdebuglist
, &showdebuglist
);
4724 add_setshow_boolean_cmd ("non-stop", no_class
,
4726 Set whether gdb controls the inferior in non-stop mode."), _("\
4727 Show whether gdb controls the inferior in non-stop mode."), _("\
4728 When debugging a multi-threaded program and this setting is\n\
4729 off (the default, also called all-stop mode), when one thread stops\n\
4730 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
4731 all other threads in the program while you interact with the thread of\n\
4732 interest. When you continue or step a thread, you can allow the other\n\
4733 threads to run, or have them remain stopped, but while you inspect any\n\
4734 thread's state, all threads stop.\n\
4736 In non-stop mode, when one thread stops, other threads can continue\n\
4737 to run freely. You'll be able to step each thread independently,\n\
4738 leave it stopped or free to run as needed."),
4744 numsigs
= (int) TARGET_SIGNAL_LAST
;
4745 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
4746 signal_print
= (unsigned char *)
4747 xmalloc (sizeof (signal_print
[0]) * numsigs
);
4748 signal_program
= (unsigned char *)
4749 xmalloc (sizeof (signal_program
[0]) * numsigs
);
4750 for (i
= 0; i
< numsigs
; i
++)
4753 signal_print
[i
] = 1;
4754 signal_program
[i
] = 1;
4757 /* Signals caused by debugger's own actions
4758 should not be given to the program afterwards. */
4759 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
4760 signal_program
[TARGET_SIGNAL_INT
] = 0;
4762 /* Signals that are not errors should not normally enter the debugger. */
4763 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
4764 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
4765 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
4766 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
4767 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
4768 signal_print
[TARGET_SIGNAL_PROF
] = 0;
4769 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
4770 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
4771 signal_stop
[TARGET_SIGNAL_IO
] = 0;
4772 signal_print
[TARGET_SIGNAL_IO
] = 0;
4773 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
4774 signal_print
[TARGET_SIGNAL_POLL
] = 0;
4775 signal_stop
[TARGET_SIGNAL_URG
] = 0;
4776 signal_print
[TARGET_SIGNAL_URG
] = 0;
4777 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
4778 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
4780 /* These signals are used internally by user-level thread
4781 implementations. (See signal(5) on Solaris.) Like the above
4782 signals, a healthy program receives and handles them as part of
4783 its normal operation. */
4784 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
4785 signal_print
[TARGET_SIGNAL_LWP
] = 0;
4786 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
4787 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
4788 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
4789 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
4791 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
4792 &stop_on_solib_events
, _("\
4793 Set stopping for shared library events."), _("\
4794 Show stopping for shared library events."), _("\
4795 If nonzero, gdb will give control to the user when the dynamic linker\n\
4796 notifies gdb of shared library events. The most common event of interest\n\
4797 to the user would be loading/unloading of a new library."),
4799 show_stop_on_solib_events
,
4800 &setlist
, &showlist
);
4802 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
4803 follow_fork_mode_kind_names
,
4804 &follow_fork_mode_string
, _("\
4805 Set debugger response to a program call of fork or vfork."), _("\
4806 Show debugger response to a program call of fork or vfork."), _("\
4807 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4808 parent - the original process is debugged after a fork\n\
4809 child - the new process is debugged after a fork\n\
4810 The unfollowed process will continue to run.\n\
4811 By default, the debugger will follow the parent process."),
4813 show_follow_fork_mode_string
,
4814 &setlist
, &showlist
);
4816 add_setshow_enum_cmd ("scheduler-locking", class_run
,
4817 scheduler_enums
, &scheduler_mode
, _("\
4818 Set mode for locking scheduler during execution."), _("\
4819 Show mode for locking scheduler during execution."), _("\
4820 off == no locking (threads may preempt at any time)\n\
4821 on == full locking (no thread except the current thread may run)\n\
4822 step == scheduler locked during every single-step operation.\n\
4823 In this mode, no other thread may run during a step command.\n\
4824 Other threads may run while stepping over a function call ('next')."),
4825 set_schedlock_func
, /* traps on target vector */
4826 show_scheduler_mode
,
4827 &setlist
, &showlist
);
4829 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
4830 Set mode of the step operation."), _("\
4831 Show mode of the step operation."), _("\
4832 When set, doing a step over a function without debug line information\n\
4833 will stop at the first instruction of that function. Otherwise, the\n\
4834 function is skipped and the step command stops at a different source line."),
4836 show_step_stop_if_no_debug
,
4837 &setlist
, &showlist
);
4839 add_setshow_boolean_cmd ("can-use-displaced-stepping", class_maintenance
,
4840 &can_use_displaced_stepping
, _("\
4841 Set debugger's willingness to use displaced stepping."), _("\
4842 Show debugger's willingness to use displaced stepping."), _("\
4843 If zero, gdb will not use displaced stepping to step over\n\
4844 breakpoints, even if such is supported by the target."),
4846 show_can_use_displaced_stepping
,
4847 &maintenance_set_cmdlist
,
4848 &maintenance_show_cmdlist
);
4850 /* ptid initializations */
4851 null_ptid
= ptid_build (0, 0, 0);
4852 minus_one_ptid
= ptid_build (-1, 0, 0);
4853 inferior_ptid
= null_ptid
;
4854 target_last_wait_ptid
= minus_one_ptid
;
4855 displaced_step_ptid
= null_ptid
;