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
);
868 /* Update global variables holding ptids to hold NEW_PTID if they were
871 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
873 struct displaced_step_request
*it
;
875 if (ptid_equal (inferior_ptid
, old_ptid
))
876 inferior_ptid
= new_ptid
;
878 if (ptid_equal (singlestep_ptid
, old_ptid
))
879 singlestep_ptid
= new_ptid
;
881 if (ptid_equal (displaced_step_ptid
, old_ptid
))
882 displaced_step_ptid
= new_ptid
;
884 if (ptid_equal (deferred_step_ptid
, old_ptid
))
885 deferred_step_ptid
= new_ptid
;
887 for (it
= displaced_step_request_queue
; it
; it
= it
->next
)
888 if (ptid_equal (it
->ptid
, old_ptid
))
895 /* Things to clean up if we QUIT out of resume (). */
897 resume_cleanups (void *ignore
)
902 static const char schedlock_off
[] = "off";
903 static const char schedlock_on
[] = "on";
904 static const char schedlock_step
[] = "step";
905 static const char *scheduler_enums
[] = {
911 static const char *scheduler_mode
= schedlock_off
;
913 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
914 struct cmd_list_element
*c
, const char *value
)
916 fprintf_filtered (file
, _("\
917 Mode for locking scheduler during execution is \"%s\".\n"),
922 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
924 if (!target_can_lock_scheduler
)
926 scheduler_mode
= schedlock_off
;
927 error (_("Target '%s' cannot support this command."), target_shortname
);
932 /* Resume the inferior, but allow a QUIT. This is useful if the user
933 wants to interrupt some lengthy single-stepping operation
934 (for child processes, the SIGINT goes to the inferior, and so
935 we get a SIGINT random_signal, but for remote debugging and perhaps
936 other targets, that's not true).
938 STEP nonzero if we should step (zero to continue instead).
939 SIG is the signal to give the inferior (zero for none). */
941 resume (int step
, enum target_signal sig
)
943 int should_resume
= 1;
944 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
945 struct regcache
*regcache
= get_current_regcache ();
946 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
947 CORE_ADDR pc
= regcache_read_pc (regcache
);
951 fprintf_unfiltered (gdb_stdlog
,
952 "infrun: resume (step=%d, signal=%d), "
953 "stepping_over_breakpoint=%d\n",
954 step
, sig
, stepping_over_breakpoint
);
956 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
957 over an instruction that causes a page fault without triggering
958 a hardware watchpoint. The kernel properly notices that it shouldn't
959 stop, because the hardware watchpoint is not triggered, but it forgets
960 the step request and continues the program normally.
961 Work around the problem by removing hardware watchpoints if a step is
962 requested, GDB will check for a hardware watchpoint trigger after the
964 if (CANNOT_STEP_HW_WATCHPOINTS
&& step
)
965 remove_hw_watchpoints ();
968 /* Normally, by the time we reach `resume', the breakpoints are either
969 removed or inserted, as appropriate. The exception is if we're sitting
970 at a permanent breakpoint; we need to step over it, but permanent
971 breakpoints can't be removed. So we have to test for it here. */
972 if (breakpoint_here_p (pc
) == permanent_breakpoint_here
)
974 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
975 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
978 The program is stopped at a permanent breakpoint, but GDB does not know\n\
979 how to step past a permanent breakpoint on this architecture. Try using\n\
980 a command like `return' or `jump' to continue execution."));
983 /* If enabled, step over breakpoints by executing a copy of the
984 instruction at a different address.
986 We can't use displaced stepping when we have a signal to deliver;
987 the comments for displaced_step_prepare explain why. The
988 comments in the handle_inferior event for dealing with 'random
989 signals' explain what we do instead. */
990 if (use_displaced_stepping (gdbarch
)
991 && stepping_over_breakpoint
992 && sig
== TARGET_SIGNAL_0
)
994 if (!displaced_step_prepare (inferior_ptid
))
996 /* Got placed in displaced stepping queue. Will be resumed
997 later when all the currently queued displaced stepping
998 requests finish. The thread is not executing at this point,
999 and the call to set_executing will be made later. But we
1000 need to call set_running here, since from frontend point of view,
1001 the thread is running. */
1002 set_running (inferior_ptid
, 1);
1003 discard_cleanups (old_cleanups
);
1008 if (step
&& gdbarch_software_single_step_p (gdbarch
))
1010 /* Do it the hard way, w/temp breakpoints */
1011 if (gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1013 /* ...and don't ask hardware to do it. */
1015 /* and do not pull these breakpoints until after a `wait' in
1016 `wait_for_inferior' */
1017 singlestep_breakpoints_inserted_p
= 1;
1018 singlestep_ptid
= inferior_ptid
;
1023 /* If there were any forks/vforks/execs that were caught and are
1024 now to be followed, then do so. */
1025 switch (pending_follow
.kind
)
1027 case TARGET_WAITKIND_FORKED
:
1028 case TARGET_WAITKIND_VFORKED
:
1029 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
1034 case TARGET_WAITKIND_EXECD
:
1035 /* follow_exec is called as soon as the exec event is seen. */
1036 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
1043 /* Install inferior's terminal modes. */
1044 target_terminal_inferior ();
1050 resume_ptid
= RESUME_ALL
; /* Default */
1052 /* If STEP is set, it's a request to use hardware stepping
1053 facilities. But in that case, we should never
1054 use singlestep breakpoint. */
1055 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1057 if (singlestep_breakpoints_inserted_p
1058 && stepping_past_singlestep_breakpoint
)
1060 /* The situation here is as follows. In thread T1 we wanted to
1061 single-step. Lacking hardware single-stepping we've
1062 set breakpoint at the PC of the next instruction -- call it
1063 P. After resuming, we've hit that breakpoint in thread T2.
1064 Now we've removed original breakpoint, inserted breakpoint
1065 at P+1, and try to step to advance T2 past breakpoint.
1066 We need to step only T2, as if T1 is allowed to freely run,
1067 it can run past P, and if other threads are allowed to run,
1068 they can hit breakpoint at P+1, and nested hits of single-step
1069 breakpoints is not something we'd want -- that's complicated
1070 to support, and has no value. */
1071 resume_ptid
= inferior_ptid
;
1074 if ((step
|| singlestep_breakpoints_inserted_p
)
1075 && stepping_over_breakpoint
)
1077 /* We're allowing a thread to run past a breakpoint it has
1078 hit, by single-stepping the thread with the breakpoint
1079 removed. In which case, we need to single-step only this
1080 thread, and keep others stopped, as they can miss this
1081 breakpoint if allowed to run.
1083 The current code actually removes all breakpoints when
1084 doing this, not just the one being stepped over, so if we
1085 let other threads run, we can actually miss any
1086 breakpoint, not just the one at PC. */
1087 resume_ptid
= inferior_ptid
;
1092 /* With non-stop mode on, threads are always handled
1094 resume_ptid
= inferior_ptid
;
1096 else if ((scheduler_mode
== schedlock_on
)
1097 || (scheduler_mode
== schedlock_step
1098 && (step
|| singlestep_breakpoints_inserted_p
)))
1100 /* User-settable 'scheduler' mode requires solo thread resume. */
1101 resume_ptid
= inferior_ptid
;
1104 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1106 /* Most targets can step a breakpoint instruction, thus
1107 executing it normally. But if this one cannot, just
1108 continue and we will hit it anyway. */
1109 if (step
&& breakpoint_inserted_here_p (pc
))
1114 && use_displaced_stepping (gdbarch
)
1115 && stepping_over_breakpoint
)
1117 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1118 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1121 fprintf_unfiltered (gdb_stdlog
, "displaced: run 0x%s: ",
1122 paddr_nz (actual_pc
));
1123 read_memory (actual_pc
, buf
, sizeof (buf
));
1124 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1127 target_resume (resume_ptid
, step
, sig
);
1130 discard_cleanups (old_cleanups
);
1135 /* Clear out all variables saying what to do when inferior is continued.
1136 First do this, then set the ones you want, then call `proceed'. */
1139 clear_proceed_status (void)
1141 stepping_over_breakpoint
= 0;
1142 step_range_start
= 0;
1144 step_frame_id
= null_frame_id
;
1145 step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1146 stop_after_trap
= 0;
1147 stop_soon
= NO_STOP_QUIETLY
;
1148 proceed_to_finish
= 0;
1149 breakpoint_proceeded
= 1; /* We're about to proceed... */
1153 regcache_xfree (stop_registers
);
1154 stop_registers
= NULL
;
1157 /* Discard any remaining commands or status from previous stop. */
1158 bpstat_clear (&stop_bpstat
);
1161 /* This should be suitable for any targets that support threads. */
1164 prepare_to_proceed (int step
)
1167 struct target_waitstatus wait_status
;
1169 /* Get the last target status returned by target_wait(). */
1170 get_last_target_status (&wait_ptid
, &wait_status
);
1172 /* Make sure we were stopped at a breakpoint. */
1173 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
1174 || wait_status
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1179 /* Switched over from WAIT_PID. */
1180 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
1181 && !ptid_equal (inferior_ptid
, wait_ptid
))
1183 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
1185 if (breakpoint_here_p (regcache_read_pc (regcache
)))
1187 /* If stepping, remember current thread to switch back to. */
1189 deferred_step_ptid
= inferior_ptid
;
1191 /* Switch back to WAIT_PID thread. */
1192 switch_to_thread (wait_ptid
);
1194 /* We return 1 to indicate that there is a breakpoint here,
1195 so we need to step over it before continuing to avoid
1196 hitting it straight away. */
1204 /* Record the pc of the program the last time it stopped. This is
1205 just used internally by wait_for_inferior, but need to be preserved
1206 over calls to it and cleared when the inferior is started. */
1207 static CORE_ADDR prev_pc
;
1209 /* Basic routine for continuing the program in various fashions.
1211 ADDR is the address to resume at, or -1 for resume where stopped.
1212 SIGGNAL is the signal to give it, or 0 for none,
1213 or -1 for act according to how it stopped.
1214 STEP is nonzero if should trap after one instruction.
1215 -1 means return after that and print nothing.
1216 You should probably set various step_... variables
1217 before calling here, if you are stepping.
1219 You should call clear_proceed_status before calling proceed. */
1222 proceed (CORE_ADDR addr
, enum target_signal siggnal
, int step
)
1224 struct regcache
*regcache
= get_current_regcache ();
1225 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1226 CORE_ADDR pc
= regcache_read_pc (regcache
);
1230 step_start_function
= find_pc_function (pc
);
1232 stop_after_trap
= 1;
1234 if (addr
== (CORE_ADDR
) -1)
1236 if (pc
== stop_pc
&& breakpoint_here_p (pc
))
1237 /* There is a breakpoint at the address we will resume at,
1238 step one instruction before inserting breakpoints so that
1239 we do not stop right away (and report a second hit at this
1242 else if (gdbarch_single_step_through_delay_p (gdbarch
)
1243 && gdbarch_single_step_through_delay (gdbarch
,
1244 get_current_frame ()))
1245 /* We stepped onto an instruction that needs to be stepped
1246 again before re-inserting the breakpoint, do so. */
1251 regcache_write_pc (regcache
, addr
);
1255 fprintf_unfiltered (gdb_stdlog
,
1256 "infrun: proceed (addr=0x%s, signal=%d, step=%d)\n",
1257 paddr_nz (addr
), siggnal
, step
);
1260 /* In non-stop, each thread is handled individually. The context
1261 must already be set to the right thread here. */
1265 /* In a multi-threaded task we may select another thread and
1266 then continue or step.
1268 But if the old thread was stopped at a breakpoint, it will
1269 immediately cause another breakpoint stop without any
1270 execution (i.e. it will report a breakpoint hit incorrectly).
1271 So we must step over it first.
1273 prepare_to_proceed checks the current thread against the
1274 thread that reported the most recent event. If a step-over
1275 is required it returns TRUE and sets the current thread to
1277 if (prepare_to_proceed (step
))
1283 stepping_over_breakpoint
= 1;
1284 /* If displaced stepping is enabled, we can step over the
1285 breakpoint without hitting it, so leave all breakpoints
1286 inserted. Otherwise we need to disable all breakpoints, step
1287 one instruction, and then re-add them when that step is
1289 if (!use_displaced_stepping (gdbarch
))
1290 remove_breakpoints ();
1293 /* We can insert breakpoints if we're not trying to step over one,
1294 or if we are stepping over one but we're using displaced stepping
1296 if (! stepping_over_breakpoint
|| use_displaced_stepping (gdbarch
))
1297 insert_breakpoints ();
1299 if (siggnal
!= TARGET_SIGNAL_DEFAULT
)
1300 stop_signal
= siggnal
;
1301 /* If this signal should not be seen by program,
1302 give it zero. Used for debugging signals. */
1303 else if (!signal_program
[stop_signal
])
1304 stop_signal
= TARGET_SIGNAL_0
;
1306 annotate_starting ();
1308 /* Make sure that output from GDB appears before output from the
1310 gdb_flush (gdb_stdout
);
1312 /* Refresh prev_pc value just prior to resuming. This used to be
1313 done in stop_stepping, however, setting prev_pc there did not handle
1314 scenarios such as inferior function calls or returning from
1315 a function via the return command. In those cases, the prev_pc
1316 value was not set properly for subsequent commands. The prev_pc value
1317 is used to initialize the starting line number in the ecs. With an
1318 invalid value, the gdb next command ends up stopping at the position
1319 represented by the next line table entry past our start position.
1320 On platforms that generate one line table entry per line, this
1321 is not a problem. However, on the ia64, the compiler generates
1322 extraneous line table entries that do not increase the line number.
1323 When we issue the gdb next command on the ia64 after an inferior call
1324 or a return command, we often end up a few instructions forward, still
1325 within the original line we started.
1327 An attempt was made to have init_execution_control_state () refresh
1328 the prev_pc value before calculating the line number. This approach
1329 did not work because on platforms that use ptrace, the pc register
1330 cannot be read unless the inferior is stopped. At that point, we
1331 are not guaranteed the inferior is stopped and so the regcache_read_pc ()
1332 call can fail. Setting the prev_pc value here ensures the value is
1333 updated correctly when the inferior is stopped. */
1334 prev_pc
= regcache_read_pc (get_current_regcache ());
1336 /* Fill in with reasonable starting values. */
1337 init_thread_stepping_state (tss
);
1339 /* We'll update this if & when we switch to a new thread. */
1340 previous_inferior_ptid
= inferior_ptid
;
1342 /* Reset to normal state. */
1343 init_infwait_state ();
1345 /* Resume inferior. */
1346 resume (oneproc
|| step
|| bpstat_should_step (), stop_signal
);
1348 /* Wait for it to stop (if not standalone)
1349 and in any case decode why it stopped, and act accordingly. */
1350 /* Do this only if we are not using the event loop, or if the target
1351 does not support asynchronous execution. */
1352 if (!target_can_async_p ())
1354 wait_for_inferior (0);
1360 /* Start remote-debugging of a machine over a serial link. */
1363 start_remote (int from_tty
)
1365 init_wait_for_inferior ();
1366 stop_soon
= STOP_QUIETLY_REMOTE
;
1367 stepping_over_breakpoint
= 0;
1369 /* Always go on waiting for the target, regardless of the mode. */
1370 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1371 indicate to wait_for_inferior that a target should timeout if
1372 nothing is returned (instead of just blocking). Because of this,
1373 targets expecting an immediate response need to, internally, set
1374 things up so that the target_wait() is forced to eventually
1376 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1377 differentiate to its caller what the state of the target is after
1378 the initial open has been performed. Here we're assuming that
1379 the target has stopped. It should be possible to eventually have
1380 target_open() return to the caller an indication that the target
1381 is currently running and GDB state should be set to the same as
1382 for an async run. */
1383 wait_for_inferior (0);
1385 /* Now that the inferior has stopped, do any bookkeeping like
1386 loading shared libraries. We want to do this before normal_stop,
1387 so that the displayed frame is up to date. */
1388 post_create_inferior (¤t_target
, from_tty
);
1393 /* Initialize static vars when a new inferior begins. */
1396 init_wait_for_inferior (void)
1398 /* These are meaningless until the first time through wait_for_inferior. */
1401 breakpoint_init_inferior (inf_starting
);
1403 /* Don't confuse first call to proceed(). */
1404 stop_signal
= TARGET_SIGNAL_0
;
1406 /* The first resume is not following a fork/vfork/exec. */
1407 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
; /* I.e., none. */
1409 clear_proceed_status ();
1411 stepping_past_singlestep_breakpoint
= 0;
1412 deferred_step_ptid
= null_ptid
;
1414 target_last_wait_ptid
= minus_one_ptid
;
1416 init_thread_stepping_state (tss
);
1417 previous_inferior_ptid
= null_ptid
;
1418 init_infwait_state ();
1420 displaced_step_clear ();
1424 /* This enum encodes possible reasons for doing a target_wait, so that
1425 wfi can call target_wait in one place. (Ultimately the call will be
1426 moved out of the infinite loop entirely.) */
1430 infwait_normal_state
,
1431 infwait_thread_hop_state
,
1432 infwait_step_watch_state
,
1433 infwait_nonstep_watch_state
1436 /* Why did the inferior stop? Used to print the appropriate messages
1437 to the interface from within handle_inferior_event(). */
1438 enum inferior_stop_reason
1440 /* Step, next, nexti, stepi finished. */
1442 /* Inferior terminated by signal. */
1444 /* Inferior exited. */
1446 /* Inferior received signal, and user asked to be notified. */
1450 /* The PTID we'll do a target_wait on.*/
1453 /* Current inferior wait state. */
1454 enum infwait_states infwait_state
;
1456 /* Data to be passed around while handling an event. This data is
1457 discarded between events. */
1458 struct execution_control_state
1461 struct target_waitstatus ws
;
1463 CORE_ADDR stop_func_start
;
1464 CORE_ADDR stop_func_end
;
1465 char *stop_func_name
;
1466 int new_thread_event
;
1470 void init_execution_control_state (struct execution_control_state
*ecs
);
1472 void handle_inferior_event (struct execution_control_state
*ecs
);
1474 static void step_into_function (struct execution_control_state
*ecs
);
1475 static void insert_step_resume_breakpoint_at_frame (struct frame_info
*step_frame
);
1476 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
1477 static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
1478 struct frame_id sr_id
);
1479 static void insert_longjmp_resume_breakpoint (CORE_ADDR
);
1481 static void stop_stepping (struct execution_control_state
*ecs
);
1482 static void prepare_to_wait (struct execution_control_state
*ecs
);
1483 static void keep_going (struct execution_control_state
*ecs
);
1484 static void print_stop_reason (enum inferior_stop_reason stop_reason
,
1487 /* Wait for control to return from inferior to debugger.
1489 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
1490 as if they were SIGTRAP signals. This can be useful during
1491 the startup sequence on some targets such as HP/UX, where
1492 we receive an EXEC event instead of the expected SIGTRAP.
1494 If inferior gets a signal, we may decide to start it up again
1495 instead of returning. That is why there is a loop in this function.
1496 When this function actually returns it means the inferior
1497 should be left stopped and GDB should read more commands. */
1500 wait_for_inferior (int treat_exec_as_sigtrap
)
1502 struct cleanup
*old_cleanups
;
1503 struct execution_control_state ecss
;
1504 struct execution_control_state
*ecs
;
1508 (gdb_stdlog
, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
1509 treat_exec_as_sigtrap
);
1511 old_cleanups
= make_cleanup (delete_step_resume_breakpoint
,
1512 &step_resume_breakpoint
);
1515 memset (ecs
, 0, sizeof (*ecs
));
1517 overlay_cache_invalid
= 1;
1519 /* We have to invalidate the registers BEFORE calling target_wait
1520 because they can be loaded from the target while in target_wait.
1521 This makes remote debugging a bit more efficient for those
1522 targets that provide critical registers as part of their normal
1523 status mechanism. */
1525 registers_changed ();
1529 if (deprecated_target_wait_hook
)
1530 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
);
1532 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
);
1534 if (treat_exec_as_sigtrap
&& ecs
->ws
.kind
== TARGET_WAITKIND_EXECD
)
1536 xfree (ecs
->ws
.value
.execd_pathname
);
1537 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
1538 ecs
->ws
.value
.sig
= TARGET_SIGNAL_TRAP
;
1541 /* Now figure out what to do with the result of the result. */
1542 handle_inferior_event (ecs
);
1544 if (!ecs
->wait_some_more
)
1547 do_cleanups (old_cleanups
);
1550 /* Asynchronous version of wait_for_inferior. It is called by the
1551 event loop whenever a change of state is detected on the file
1552 descriptor corresponding to the target. It can be called more than
1553 once to complete a single execution command. In such cases we need
1554 to keep the state in a global variable ECSS. If it is the last time
1555 that this function is called for a single execution command, then
1556 report to the user that the inferior has stopped, and do the
1557 necessary cleanups. */
1560 fetch_inferior_event (void *client_data
)
1562 struct execution_control_state ecss
;
1563 struct execution_control_state
*ecs
= &ecss
;
1564 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
1565 int was_sync
= sync_execution
;
1567 memset (ecs
, 0, sizeof (*ecs
));
1569 overlay_cache_invalid
= 1;
1572 /* In non-stop mode, the user/frontend should not notice a thread
1573 switch due to internal events. Make sure we reverse to the
1574 user selected thread and frame after handling the event and
1575 running any breakpoint commands. */
1576 make_cleanup_restore_current_thread ();
1578 /* We have to invalidate the registers BEFORE calling target_wait
1579 because they can be loaded from the target while in target_wait.
1580 This makes remote debugging a bit more efficient for those
1581 targets that provide critical registers as part of their normal
1582 status mechanism. */
1584 registers_changed ();
1586 if (deprecated_target_wait_hook
)
1588 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
);
1590 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
);
1593 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
1594 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1595 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
1596 /* In non-stop mode, each thread is handled individually. Switch
1597 early, so the global state is set correctly for this
1599 context_switch (ecs
->ptid
);
1601 /* Now figure out what to do with the result of the result. */
1602 handle_inferior_event (ecs
);
1604 if (!ecs
->wait_some_more
)
1606 delete_step_resume_breakpoint (&step_resume_breakpoint
);
1608 if (stop_soon
== NO_STOP_QUIETLY
)
1611 if (step_multi
&& stop_step
)
1612 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
1614 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
1617 /* Revert thread and frame. */
1618 do_cleanups (old_chain
);
1620 /* If the inferior was in sync execution mode, and now isn't,
1621 restore the prompt. */
1622 if (was_sync
&& !sync_execution
)
1623 display_gdb_prompt (0);
1626 /* Prepare an execution control state for looping through a
1627 wait_for_inferior-type loop. */
1630 init_execution_control_state (struct execution_control_state
*ecs
)
1632 ecs
->random_signal
= 0;
1635 /* Clear context switchable stepping state. */
1638 init_thread_stepping_state (struct thread_stepping_state
*tss
)
1640 struct symtab_and_line sal
;
1642 tss
->stepping_over_breakpoint
= 0;
1643 tss
->step_after_step_resume_breakpoint
= 0;
1644 tss
->stepping_through_solib_after_catch
= 0;
1645 tss
->stepping_through_solib_catchpoints
= NULL
;
1647 sal
= find_pc_line (prev_pc
, 0);
1648 tss
->current_line
= sal
.line
;
1649 tss
->current_symtab
= sal
.symtab
;
1652 /* Return the cached copy of the last pid/waitstatus returned by
1653 target_wait()/deprecated_target_wait_hook(). The data is actually
1654 cached by handle_inferior_event(), which gets called immediately
1655 after target_wait()/deprecated_target_wait_hook(). */
1658 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
1660 *ptidp
= target_last_wait_ptid
;
1661 *status
= target_last_waitstatus
;
1665 nullify_last_target_wait_ptid (void)
1667 target_last_wait_ptid
= minus_one_ptid
;
1670 /* Switch thread contexts, maintaining "infrun state". */
1673 context_switch (ptid_t ptid
)
1675 /* Caution: it may happen that the new thread (or the old one!)
1676 is not in the thread list. In this case we must not attempt
1677 to "switch context", or we run the risk that our context may
1678 be lost. This may happen as a result of the target module
1679 mishandling thread creation. */
1683 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
1684 target_pid_to_str (inferior_ptid
));
1685 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
1686 target_pid_to_str (ptid
));
1689 if (in_thread_list (inferior_ptid
) && in_thread_list (ptid
))
1690 { /* Perform infrun state context switch: */
1691 /* Save infrun state for the old thread. */
1692 save_infrun_state (inferior_ptid
, prev_pc
,
1693 stepping_over_breakpoint
, step_resume_breakpoint
,
1695 step_range_end
, &step_frame_id
,
1696 tss
->stepping_over_breakpoint
,
1697 tss
->stepping_through_solib_after_catch
,
1698 tss
->stepping_through_solib_catchpoints
,
1699 tss
->current_line
, tss
->current_symtab
,
1700 cmd_continuation
, intermediate_continuation
,
1708 /* Load infrun state for the new thread. */
1709 load_infrun_state (ptid
, &prev_pc
,
1710 &stepping_over_breakpoint
, &step_resume_breakpoint
,
1712 &step_range_end
, &step_frame_id
,
1713 &tss
->stepping_over_breakpoint
,
1714 &tss
->stepping_through_solib_after_catch
,
1715 &tss
->stepping_through_solib_catchpoints
,
1716 &tss
->current_line
, &tss
->current_symtab
,
1717 &cmd_continuation
, &intermediate_continuation
,
1726 switch_to_thread (ptid
);
1729 /* Context switch to thread PTID. */
1731 context_switch_to (ptid_t ptid
)
1733 ptid_t current_ptid
= inferior_ptid
;
1735 /* Context switch to the new thread. */
1736 if (!ptid_equal (ptid
, inferior_ptid
))
1738 context_switch (ptid
);
1740 return current_ptid
;
1744 adjust_pc_after_break (struct execution_control_state
*ecs
)
1746 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
1747 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1748 CORE_ADDR breakpoint_pc
;
1750 /* If this target does not decrement the PC after breakpoints, then
1751 we have nothing to do. */
1752 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
1755 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
1756 we aren't, just return.
1758 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
1759 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
1760 implemented by software breakpoints should be handled through the normal
1763 NOTE drow/2004-01-31: On some targets, breakpoints may generate
1764 different signals (SIGILL or SIGEMT for instance), but it is less
1765 clear where the PC is pointing afterwards. It may not match
1766 gdbarch_decr_pc_after_break. I don't know any specific target that
1767 generates these signals at breakpoints (the code has been in GDB since at
1768 least 1992) so I can not guess how to handle them here.
1770 In earlier versions of GDB, a target with
1771 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
1772 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
1773 target with both of these set in GDB history, and it seems unlikely to be
1774 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
1776 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
1779 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1782 /* Find the location where (if we've hit a breakpoint) the
1783 breakpoint would be. */
1784 breakpoint_pc
= regcache_read_pc (regcache
)
1785 - gdbarch_decr_pc_after_break (gdbarch
);
1787 /* Check whether there actually is a software breakpoint inserted
1788 at that location. */
1789 if (software_breakpoint_inserted_here_p (breakpoint_pc
))
1791 /* When using hardware single-step, a SIGTRAP is reported for both
1792 a completed single-step and a software breakpoint. Need to
1793 differentiate between the two, as the latter needs adjusting
1794 but the former does not.
1796 The SIGTRAP can be due to a completed hardware single-step only if
1797 - we didn't insert software single-step breakpoints
1798 - the thread to be examined is still the current thread
1799 - this thread is currently being stepped
1801 If any of these events did not occur, we must have stopped due
1802 to hitting a software breakpoint, and have to back up to the
1805 As a special case, we could have hardware single-stepped a
1806 software breakpoint. In this case (prev_pc == breakpoint_pc),
1807 we also need to back up to the breakpoint address. */
1809 if (singlestep_breakpoints_inserted_p
1810 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
1811 || !currently_stepping (tss
)
1812 || prev_pc
== breakpoint_pc
)
1813 regcache_write_pc (regcache
, breakpoint_pc
);
1818 init_infwait_state (void)
1820 waiton_ptid
= pid_to_ptid (-1);
1821 infwait_state
= infwait_normal_state
;
1825 error_is_running (void)
1828 Cannot execute this command while the selected thread is running."));
1832 ensure_not_running (void)
1834 if (is_running (inferior_ptid
))
1835 error_is_running ();
1838 /* Given an execution control state that has been freshly filled in
1839 by an event from the inferior, figure out what it means and take
1840 appropriate action. */
1843 handle_inferior_event (struct execution_control_state
*ecs
)
1845 int sw_single_step_trap_p
= 0;
1846 int stopped_by_watchpoint
;
1847 int stepped_after_stopped_by_watchpoint
= 0;
1848 struct symtab_and_line stop_pc_sal
;
1850 breakpoint_retire_moribund ();
1852 /* Cache the last pid/waitstatus. */
1853 target_last_wait_ptid
= ecs
->ptid
;
1854 target_last_waitstatus
= ecs
->ws
;
1856 /* Always clear state belonging to the previous time we stopped. */
1857 stop_stack_dummy
= 0;
1859 adjust_pc_after_break (ecs
);
1861 reinit_frame_cache ();
1863 /* If it's a new process, add it to the thread database */
1865 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
1866 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
1867 && !in_thread_list (ecs
->ptid
));
1869 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1870 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
1871 add_thread (ecs
->ptid
);
1873 if (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
1875 /* Mark the non-executing threads accordingly. */
1877 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
1878 || ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
1879 set_executing (pid_to_ptid (-1), 0);
1881 set_executing (ecs
->ptid
, 0);
1884 switch (infwait_state
)
1886 case infwait_thread_hop_state
:
1888 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
1889 /* Cancel the waiton_ptid. */
1890 waiton_ptid
= pid_to_ptid (-1);
1893 case infwait_normal_state
:
1895 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
1898 case infwait_step_watch_state
:
1900 fprintf_unfiltered (gdb_stdlog
,
1901 "infrun: infwait_step_watch_state\n");
1903 stepped_after_stopped_by_watchpoint
= 1;
1906 case infwait_nonstep_watch_state
:
1908 fprintf_unfiltered (gdb_stdlog
,
1909 "infrun: infwait_nonstep_watch_state\n");
1910 insert_breakpoints ();
1912 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1913 handle things like signals arriving and other things happening
1914 in combination correctly? */
1915 stepped_after_stopped_by_watchpoint
= 1;
1919 internal_error (__FILE__
, __LINE__
, _("bad switch"));
1921 infwait_state
= infwait_normal_state
;
1923 switch (ecs
->ws
.kind
)
1925 case TARGET_WAITKIND_LOADED
:
1927 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
1928 /* Ignore gracefully during startup of the inferior, as it might
1929 be the shell which has just loaded some objects, otherwise
1930 add the symbols for the newly loaded objects. Also ignore at
1931 the beginning of an attach or remote session; we will query
1932 the full list of libraries once the connection is
1934 if (stop_soon
== NO_STOP_QUIETLY
)
1936 /* Check for any newly added shared libraries if we're
1937 supposed to be adding them automatically. Switch
1938 terminal for any messages produced by
1939 breakpoint_re_set. */
1940 target_terminal_ours_for_output ();
1941 /* NOTE: cagney/2003-11-25: Make certain that the target
1942 stack's section table is kept up-to-date. Architectures,
1943 (e.g., PPC64), use the section table to perform
1944 operations such as address => section name and hence
1945 require the table to contain all sections (including
1946 those found in shared libraries). */
1947 /* NOTE: cagney/2003-11-25: Pass current_target and not
1948 exec_ops to SOLIB_ADD. This is because current GDB is
1949 only tooled to propagate section_table changes out from
1950 the "current_target" (see target_resize_to_sections), and
1951 not up from the exec stratum. This, of course, isn't
1952 right. "infrun.c" should only interact with the
1953 exec/process stratum, instead relying on the target stack
1954 to propagate relevant changes (stop, section table
1955 changed, ...) up to other layers. */
1957 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
1959 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
1961 target_terminal_inferior ();
1963 /* If requested, stop when the dynamic linker notifies
1964 gdb of events. This allows the user to get control
1965 and place breakpoints in initializer routines for
1966 dynamically loaded objects (among other things). */
1967 if (stop_on_solib_events
)
1969 stop_stepping (ecs
);
1973 /* NOTE drow/2007-05-11: This might be a good place to check
1974 for "catch load". */
1977 /* If we are skipping through a shell, or through shared library
1978 loading that we aren't interested in, resume the program. If
1979 we're running the program normally, also resume. But stop if
1980 we're attaching or setting up a remote connection. */
1981 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
1983 /* Loading of shared libraries might have changed breakpoint
1984 addresses. Make sure new breakpoints are inserted. */
1985 if (stop_soon
== NO_STOP_QUIETLY
1986 && !breakpoints_always_inserted_mode ())
1987 insert_breakpoints ();
1988 resume (0, TARGET_SIGNAL_0
);
1989 prepare_to_wait (ecs
);
1995 case TARGET_WAITKIND_SPURIOUS
:
1997 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
1998 resume (0, TARGET_SIGNAL_0
);
1999 prepare_to_wait (ecs
);
2002 case TARGET_WAITKIND_EXITED
:
2004 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
2005 target_terminal_ours (); /* Must do this before mourn anyway */
2006 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
2008 /* Record the exit code in the convenience variable $_exitcode, so
2009 that the user can inspect this again later. */
2010 set_internalvar (lookup_internalvar ("_exitcode"),
2011 value_from_longest (builtin_type_int
,
2012 (LONGEST
) ecs
->ws
.value
.integer
));
2013 gdb_flush (gdb_stdout
);
2014 target_mourn_inferior ();
2015 singlestep_breakpoints_inserted_p
= 0;
2016 stop_print_frame
= 0;
2017 stop_stepping (ecs
);
2020 case TARGET_WAITKIND_SIGNALLED
:
2022 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2023 stop_print_frame
= 0;
2024 stop_signal
= ecs
->ws
.value
.sig
;
2025 target_terminal_ours (); /* Must do this before mourn anyway */
2027 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2028 reach here unless the inferior is dead. However, for years
2029 target_kill() was called here, which hints that fatal signals aren't
2030 really fatal on some systems. If that's true, then some changes
2032 target_mourn_inferior ();
2034 print_stop_reason (SIGNAL_EXITED
, stop_signal
);
2035 singlestep_breakpoints_inserted_p
= 0;
2036 stop_stepping (ecs
);
2039 /* The following are the only cases in which we keep going;
2040 the above cases end in a continue or goto. */
2041 case TARGET_WAITKIND_FORKED
:
2042 case TARGET_WAITKIND_VFORKED
:
2044 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2045 stop_signal
= TARGET_SIGNAL_TRAP
;
2046 pending_follow
.kind
= ecs
->ws
.kind
;
2048 pending_follow
.fork_event
.parent_pid
= ecs
->ptid
;
2049 pending_follow
.fork_event
.child_pid
= ecs
->ws
.value
.related_pid
;
2051 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2053 context_switch (ecs
->ptid
);
2054 reinit_frame_cache ();
2057 stop_pc
= read_pc ();
2059 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2061 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2063 /* If no catchpoint triggered for this, then keep going. */
2064 if (ecs
->random_signal
)
2066 stop_signal
= TARGET_SIGNAL_0
;
2070 goto process_event_stop_test
;
2072 case TARGET_WAITKIND_EXECD
:
2074 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
2075 stop_signal
= TARGET_SIGNAL_TRAP
;
2077 pending_follow
.execd_pathname
=
2078 savestring (ecs
->ws
.value
.execd_pathname
,
2079 strlen (ecs
->ws
.value
.execd_pathname
));
2081 /* This causes the eventpoints and symbol table to be reset. Must
2082 do this now, before trying to determine whether to stop. */
2083 follow_exec (inferior_ptid
, pending_follow
.execd_pathname
);
2084 xfree (pending_follow
.execd_pathname
);
2086 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2089 /* The breakpoints module may need to touch the inferior's
2090 memory. Switch to the (stopped) event ptid
2092 ptid_t saved_inferior_ptid
= inferior_ptid
;
2093 inferior_ptid
= ecs
->ptid
;
2095 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2097 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2098 inferior_ptid
= saved_inferior_ptid
;
2101 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2103 context_switch (ecs
->ptid
);
2104 reinit_frame_cache ();
2107 /* If no catchpoint triggered for this, then keep going. */
2108 if (ecs
->random_signal
)
2110 stop_signal
= TARGET_SIGNAL_0
;
2114 goto process_event_stop_test
;
2116 /* Be careful not to try to gather much state about a thread
2117 that's in a syscall. It's frequently a losing proposition. */
2118 case TARGET_WAITKIND_SYSCALL_ENTRY
:
2120 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2121 resume (0, TARGET_SIGNAL_0
);
2122 prepare_to_wait (ecs
);
2125 /* Before examining the threads further, step this thread to
2126 get it entirely out of the syscall. (We get notice of the
2127 event when the thread is just on the verge of exiting a
2128 syscall. Stepping one instruction seems to get it back
2130 case TARGET_WAITKIND_SYSCALL_RETURN
:
2132 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2133 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
);
2134 prepare_to_wait (ecs
);
2137 case TARGET_WAITKIND_STOPPED
:
2139 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
2140 stop_signal
= ecs
->ws
.value
.sig
;
2143 /* We had an event in the inferior, but we are not interested
2144 in handling it at this level. The lower layers have already
2145 done what needs to be done, if anything.
2147 One of the possible circumstances for this is when the
2148 inferior produces output for the console. The inferior has
2149 not stopped, and we are ignoring the event. Another possible
2150 circumstance is any event which the lower level knows will be
2151 reported multiple times without an intervening resume. */
2152 case TARGET_WAITKIND_IGNORE
:
2154 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2155 prepare_to_wait (ecs
);
2159 if (ecs
->new_thread_event
)
2162 /* Non-stop assumes that the target handles adding new threads
2163 to the thread list. */
2164 internal_error (__FILE__
, __LINE__
, "\
2165 targets should add new threads to the thread list themselves in non-stop mode.");
2167 /* We may want to consider not doing a resume here in order to
2168 give the user a chance to play with the new thread. It might
2169 be good to make that a user-settable option. */
2171 /* At this point, all threads are stopped (happens automatically
2172 in either the OS or the native code). Therefore we need to
2173 continue all threads in order to make progress. */
2175 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
2176 prepare_to_wait (ecs
);
2180 /* Do we need to clean up the state of a thread that has completed a
2181 displaced single-step? (Doing so usually affects the PC, so do
2182 it here, before we set stop_pc.) */
2183 displaced_step_fixup (ecs
->ptid
, stop_signal
);
2185 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2189 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = 0x%s\n",
2190 paddr_nz (stop_pc
));
2191 if (STOPPED_BY_WATCHPOINT (&ecs
->ws
))
2194 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
2196 if (target_stopped_data_address (¤t_target
, &addr
))
2197 fprintf_unfiltered (gdb_stdlog
,
2198 "infrun: stopped data address = 0x%s\n",
2201 fprintf_unfiltered (gdb_stdlog
,
2202 "infrun: (no data address available)\n");
2206 if (stepping_past_singlestep_breakpoint
)
2208 gdb_assert (singlestep_breakpoints_inserted_p
);
2209 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
2210 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
2212 stepping_past_singlestep_breakpoint
= 0;
2214 /* We've either finished single-stepping past the single-step
2215 breakpoint, or stopped for some other reason. It would be nice if
2216 we could tell, but we can't reliably. */
2217 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2220 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
2221 /* Pull the single step breakpoints out of the target. */
2222 remove_single_step_breakpoints ();
2223 singlestep_breakpoints_inserted_p
= 0;
2225 ecs
->random_signal
= 0;
2227 context_switch (saved_singlestep_ptid
);
2228 if (deprecated_context_hook
)
2229 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2231 resume (1, TARGET_SIGNAL_0
);
2232 prepare_to_wait (ecs
);
2237 stepping_past_singlestep_breakpoint
= 0;
2239 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
2241 /* In non-stop mode, there's never a deferred_step_ptid set. */
2242 gdb_assert (!non_stop
);
2244 /* If we stopped for some other reason than single-stepping, ignore
2245 the fact that we were supposed to switch back. */
2246 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2249 fprintf_unfiltered (gdb_stdlog
,
2250 "infrun: handling deferred step\n");
2252 /* Pull the single step breakpoints out of the target. */
2253 if (singlestep_breakpoints_inserted_p
)
2255 remove_single_step_breakpoints ();
2256 singlestep_breakpoints_inserted_p
= 0;
2259 /* Note: We do not call context_switch at this point, as the
2260 context is already set up for stepping the original thread. */
2261 switch_to_thread (deferred_step_ptid
);
2262 deferred_step_ptid
= null_ptid
;
2263 /* Suppress spurious "Switching to ..." message. */
2264 previous_inferior_ptid
= inferior_ptid
;
2266 resume (1, TARGET_SIGNAL_0
);
2267 prepare_to_wait (ecs
);
2271 deferred_step_ptid
= null_ptid
;
2274 /* See if a thread hit a thread-specific breakpoint that was meant for
2275 another thread. If so, then step that thread past the breakpoint,
2278 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2280 int thread_hop_needed
= 0;
2282 /* Check if a regular breakpoint has been hit before checking
2283 for a potential single step breakpoint. Otherwise, GDB will
2284 not see this breakpoint hit when stepping onto breakpoints. */
2285 if (regular_breakpoint_inserted_here_p (stop_pc
))
2287 ecs
->random_signal
= 0;
2288 if (!breakpoint_thread_match (stop_pc
, ecs
->ptid
))
2289 thread_hop_needed
= 1;
2291 else if (singlestep_breakpoints_inserted_p
)
2293 /* We have not context switched yet, so this should be true
2294 no matter which thread hit the singlestep breakpoint. */
2295 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
2297 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
2299 target_pid_to_str (ecs
->ptid
));
2301 ecs
->random_signal
= 0;
2302 /* The call to in_thread_list is necessary because PTIDs sometimes
2303 change when we go from single-threaded to multi-threaded. If
2304 the singlestep_ptid is still in the list, assume that it is
2305 really different from ecs->ptid. */
2306 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
2307 && in_thread_list (singlestep_ptid
))
2309 /* If the PC of the thread we were trying to single-step
2310 has changed, discard this event (which we were going
2311 to ignore anyway), and pretend we saw that thread
2312 trap. This prevents us continuously moving the
2313 single-step breakpoint forward, one instruction at a
2314 time. If the PC has changed, then the thread we were
2315 trying to single-step has trapped or been signalled,
2316 but the event has not been reported to GDB yet.
2318 There might be some cases where this loses signal
2319 information, if a signal has arrived at exactly the
2320 same time that the PC changed, but this is the best
2321 we can do with the information available. Perhaps we
2322 should arrange to report all events for all threads
2323 when they stop, or to re-poll the remote looking for
2324 this particular thread (i.e. temporarily enable
2327 CORE_ADDR new_singlestep_pc
2328 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
2330 if (new_singlestep_pc
!= singlestep_pc
)
2333 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
2334 " but expected thread advanced also\n");
2336 /* The current context still belongs to
2337 singlestep_ptid. Don't swap here, since that's
2338 the context we want to use. Just fudge our
2339 state and continue. */
2340 ecs
->ptid
= singlestep_ptid
;
2341 stop_pc
= new_singlestep_pc
;
2346 fprintf_unfiltered (gdb_stdlog
,
2347 "infrun: unexpected thread\n");
2349 thread_hop_needed
= 1;
2350 stepping_past_singlestep_breakpoint
= 1;
2351 saved_singlestep_ptid
= singlestep_ptid
;
2356 if (thread_hop_needed
)
2358 int remove_status
= 0;
2361 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
2363 /* Saw a breakpoint, but it was hit by the wrong thread.
2366 if (singlestep_breakpoints_inserted_p
)
2368 /* Pull the single step breakpoints out of the target. */
2369 remove_single_step_breakpoints ();
2370 singlestep_breakpoints_inserted_p
= 0;
2373 /* If the arch can displace step, don't remove the
2375 if (!use_displaced_stepping (current_gdbarch
))
2376 remove_status
= remove_breakpoints ();
2378 /* Did we fail to remove breakpoints? If so, try
2379 to set the PC past the bp. (There's at least
2380 one situation in which we can fail to remove
2381 the bp's: On HP-UX's that use ttrace, we can't
2382 change the address space of a vforking child
2383 process until the child exits (well, okay, not
2384 then either :-) or execs. */
2385 if (remove_status
!= 0)
2386 error (_("Cannot step over breakpoint hit in wrong thread"));
2389 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
2390 context_switch (ecs
->ptid
);
2394 /* Only need to require the next event from this
2395 thread in all-stop mode. */
2396 waiton_ptid
= ecs
->ptid
;
2397 infwait_state
= infwait_thread_hop_state
;
2400 tss
->stepping_over_breakpoint
= 1;
2402 registers_changed ();
2406 else if (singlestep_breakpoints_inserted_p
)
2408 sw_single_step_trap_p
= 1;
2409 ecs
->random_signal
= 0;
2413 ecs
->random_signal
= 1;
2415 /* See if something interesting happened to the non-current thread. If
2416 so, then switch to that thread. */
2417 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2420 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
2422 context_switch (ecs
->ptid
);
2424 if (deprecated_context_hook
)
2425 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2428 if (singlestep_breakpoints_inserted_p
)
2430 /* Pull the single step breakpoints out of the target. */
2431 remove_single_step_breakpoints ();
2432 singlestep_breakpoints_inserted_p
= 0;
2435 if (stepped_after_stopped_by_watchpoint
)
2436 stopped_by_watchpoint
= 0;
2438 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
2440 /* If necessary, step over this watchpoint. We'll be back to display
2442 if (stopped_by_watchpoint
2443 && (HAVE_STEPPABLE_WATCHPOINT
2444 || gdbarch_have_nonsteppable_watchpoint (current_gdbarch
)))
2446 /* At this point, we are stopped at an instruction which has
2447 attempted to write to a piece of memory under control of
2448 a watchpoint. The instruction hasn't actually executed
2449 yet. If we were to evaluate the watchpoint expression
2450 now, we would get the old value, and therefore no change
2451 would seem to have occurred.
2453 In order to make watchpoints work `right', we really need
2454 to complete the memory write, and then evaluate the
2455 watchpoint expression. We do this by single-stepping the
2458 It may not be necessary to disable the watchpoint to stop over
2459 it. For example, the PA can (with some kernel cooperation)
2460 single step over a watchpoint without disabling the watchpoint.
2462 It is far more common to need to disable a watchpoint to step
2463 the inferior over it. If we have non-steppable watchpoints,
2464 we must disable the current watchpoint; it's simplest to
2465 disable all watchpoints and breakpoints. */
2467 if (!HAVE_STEPPABLE_WATCHPOINT
)
2468 remove_breakpoints ();
2469 registers_changed ();
2470 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
); /* Single step */
2471 waiton_ptid
= ecs
->ptid
;
2472 if (HAVE_STEPPABLE_WATCHPOINT
)
2473 infwait_state
= infwait_step_watch_state
;
2475 infwait_state
= infwait_nonstep_watch_state
;
2476 prepare_to_wait (ecs
);
2480 ecs
->stop_func_start
= 0;
2481 ecs
->stop_func_end
= 0;
2482 ecs
->stop_func_name
= 0;
2483 /* Don't care about return value; stop_func_start and stop_func_name
2484 will both be 0 if it doesn't work. */
2485 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
2486 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
2487 ecs
->stop_func_start
2488 += gdbarch_deprecated_function_start_offset (current_gdbarch
);
2489 tss
->stepping_over_breakpoint
= 0;
2490 bpstat_clear (&stop_bpstat
);
2492 stop_print_frame
= 1;
2493 ecs
->random_signal
= 0;
2494 stopped_by_random_signal
= 0;
2496 if (stop_signal
== TARGET_SIGNAL_TRAP
2497 && stepping_over_breakpoint
2498 && gdbarch_single_step_through_delay_p (current_gdbarch
)
2499 && currently_stepping (tss
))
2501 /* We're trying to step off a breakpoint. Turns out that we're
2502 also on an instruction that needs to be stepped multiple
2503 times before it's been fully executing. E.g., architectures
2504 with a delay slot. It needs to be stepped twice, once for
2505 the instruction and once for the delay slot. */
2506 int step_through_delay
2507 = gdbarch_single_step_through_delay (current_gdbarch
,
2508 get_current_frame ());
2509 if (debug_infrun
&& step_through_delay
)
2510 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
2511 if (step_range_end
== 0 && step_through_delay
)
2513 /* The user issued a continue when stopped at a breakpoint.
2514 Set up for another trap and get out of here. */
2515 tss
->stepping_over_breakpoint
= 1;
2519 else if (step_through_delay
)
2521 /* The user issued a step when stopped at a breakpoint.
2522 Maybe we should stop, maybe we should not - the delay
2523 slot *might* correspond to a line of source. In any
2524 case, don't decide that here, just set
2525 ecs->stepping_over_breakpoint, making sure we
2526 single-step again before breakpoints are re-inserted. */
2527 tss
->stepping_over_breakpoint
= 1;
2531 /* Look at the cause of the stop, and decide what to do.
2532 The alternatives are:
2533 1) stop_stepping and return; to really stop and return to the debugger,
2534 2) keep_going and return to start up again
2535 (set tss->stepping_over_breakpoint to 1 to single step once)
2536 3) set ecs->random_signal to 1, and the decision between 1 and 2
2537 will be made according to the signal handling tables. */
2539 /* First, distinguish signals caused by the debugger from signals
2540 that have to do with the program's own actions. Note that
2541 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
2542 on the operating system version. Here we detect when a SIGILL or
2543 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
2544 something similar for SIGSEGV, since a SIGSEGV will be generated
2545 when we're trying to execute a breakpoint instruction on a
2546 non-executable stack. This happens for call dummy breakpoints
2547 for architectures like SPARC that place call dummies on the
2550 If we're doing a displaced step past a breakpoint, then the
2551 breakpoint is always inserted at the original instruction;
2552 non-standard signals can't be explained by the breakpoint. */
2553 if (stop_signal
== TARGET_SIGNAL_TRAP
2554 || (! stepping_over_breakpoint
2555 && breakpoint_inserted_here_p (stop_pc
)
2556 && (stop_signal
== TARGET_SIGNAL_ILL
2557 || stop_signal
== TARGET_SIGNAL_SEGV
2558 || stop_signal
== TARGET_SIGNAL_EMT
))
2559 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2560 || stop_soon
== STOP_QUIETLY_REMOTE
)
2562 if (stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
2565 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
2566 stop_print_frame
= 0;
2567 stop_stepping (ecs
);
2571 /* This is originated from start_remote(), start_inferior() and
2572 shared libraries hook functions. */
2573 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
2576 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
2577 stop_stepping (ecs
);
2581 /* This originates from attach_command(). We need to overwrite
2582 the stop_signal here, because some kernels don't ignore a
2583 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
2584 See more comments in inferior.h. On the other hand, if we
2585 get a non-SIGSTOP, report it to the user - assume the backend
2586 will handle the SIGSTOP if it should show up later.
2588 Also consider that the attach is complete when we see a
2589 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
2590 target extended-remote report it instead of a SIGSTOP
2591 (e.g. gdbserver). We already rely on SIGTRAP being our
2592 signal, so this is no exception. */
2593 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2594 && (stop_signal
== TARGET_SIGNAL_STOP
2595 || stop_signal
== TARGET_SIGNAL_TRAP
))
2597 stop_stepping (ecs
);
2598 stop_signal
= TARGET_SIGNAL_0
;
2602 /* See if there is a breakpoint at the current PC. */
2603 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2605 /* Following in case break condition called a
2607 stop_print_frame
= 1;
2609 /* NOTE: cagney/2003-03-29: These two checks for a random signal
2610 at one stage in the past included checks for an inferior
2611 function call's call dummy's return breakpoint. The original
2612 comment, that went with the test, read:
2614 ``End of a stack dummy. Some systems (e.g. Sony news) give
2615 another signal besides SIGTRAP, so check here as well as
2618 If someone ever tries to get get call dummys on a
2619 non-executable stack to work (where the target would stop
2620 with something like a SIGSEGV), then those tests might need
2621 to be re-instated. Given, however, that the tests were only
2622 enabled when momentary breakpoints were not being used, I
2623 suspect that it won't be the case.
2625 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
2626 be necessary for call dummies on a non-executable stack on
2629 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2631 = !(bpstat_explains_signal (stop_bpstat
)
2632 || stepping_over_breakpoint
2633 || (step_range_end
&& step_resume_breakpoint
== NULL
));
2636 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2637 if (!ecs
->random_signal
)
2638 stop_signal
= TARGET_SIGNAL_TRAP
;
2642 /* When we reach this point, we've pretty much decided
2643 that the reason for stopping must've been a random
2644 (unexpected) signal. */
2647 ecs
->random_signal
= 1;
2649 process_event_stop_test
:
2650 /* For the program's own signals, act according to
2651 the signal handling tables. */
2653 if (ecs
->random_signal
)
2655 /* Signal not for debugging purposes. */
2659 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n", stop_signal
);
2661 stopped_by_random_signal
= 1;
2663 if (signal_print
[stop_signal
])
2666 target_terminal_ours_for_output ();
2667 print_stop_reason (SIGNAL_RECEIVED
, stop_signal
);
2669 if (signal_stop_state (stop_signal
))
2671 stop_stepping (ecs
);
2674 /* If not going to stop, give terminal back
2675 if we took it away. */
2677 target_terminal_inferior ();
2679 /* Clear the signal if it should not be passed. */
2680 if (signal_program
[stop_signal
] == 0)
2681 stop_signal
= TARGET_SIGNAL_0
;
2683 if (prev_pc
== read_pc ()
2684 && stepping_over_breakpoint
2685 && step_resume_breakpoint
== NULL
)
2687 /* We were just starting a new sequence, attempting to
2688 single-step off of a breakpoint and expecting a SIGTRAP.
2689 Instead this signal arrives. This signal will take us out
2690 of the stepping range so GDB needs to remember to, when
2691 the signal handler returns, resume stepping off that
2693 /* To simplify things, "continue" is forced to use the same
2694 code paths as single-step - set a breakpoint at the
2695 signal return address and then, once hit, step off that
2698 fprintf_unfiltered (gdb_stdlog
,
2699 "infrun: signal arrived while stepping over "
2702 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2703 tss
->step_after_step_resume_breakpoint
= 1;
2708 if (step_range_end
!= 0
2709 && stop_signal
!= TARGET_SIGNAL_0
2710 && stop_pc
>= step_range_start
&& stop_pc
< step_range_end
2711 && frame_id_eq (get_frame_id (get_current_frame ()),
2713 && step_resume_breakpoint
== NULL
)
2715 /* The inferior is about to take a signal that will take it
2716 out of the single step range. Set a breakpoint at the
2717 current PC (which is presumably where the signal handler
2718 will eventually return) and then allow the inferior to
2721 Note that this is only needed for a signal delivered
2722 while in the single-step range. Nested signals aren't a
2723 problem as they eventually all return. */
2725 fprintf_unfiltered (gdb_stdlog
,
2726 "infrun: signal may take us out of "
2727 "single-step range\n");
2729 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2734 /* Note: step_resume_breakpoint may be non-NULL. This occures
2735 when either there's a nested signal, or when there's a
2736 pending signal enabled just as the signal handler returns
2737 (leaving the inferior at the step-resume-breakpoint without
2738 actually executing it). Either way continue until the
2739 breakpoint is really hit. */
2744 /* Handle cases caused by hitting a breakpoint. */
2746 CORE_ADDR jmp_buf_pc
;
2747 struct bpstat_what what
;
2749 what
= bpstat_what (stop_bpstat
);
2751 if (what
.call_dummy
)
2753 stop_stack_dummy
= 1;
2756 switch (what
.main_action
)
2758 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
2759 /* If we hit the breakpoint at longjmp while stepping, we
2760 install a momentary breakpoint at the target of the
2764 fprintf_unfiltered (gdb_stdlog
,
2765 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
2767 tss
->stepping_over_breakpoint
= 1;
2769 if (!gdbarch_get_longjmp_target_p (current_gdbarch
)
2770 || !gdbarch_get_longjmp_target (current_gdbarch
,
2771 get_current_frame (), &jmp_buf_pc
))
2774 fprintf_unfiltered (gdb_stdlog
, "\
2775 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
2780 /* We're going to replace the current step-resume breakpoint
2781 with a longjmp-resume breakpoint. */
2782 if (step_resume_breakpoint
!= NULL
)
2783 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2785 /* Insert a breakpoint at resume address. */
2786 insert_longjmp_resume_breakpoint (jmp_buf_pc
);
2791 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
2793 fprintf_unfiltered (gdb_stdlog
,
2794 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
2796 gdb_assert (step_resume_breakpoint
!= NULL
);
2797 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2800 print_stop_reason (END_STEPPING_RANGE
, 0);
2801 stop_stepping (ecs
);
2804 case BPSTAT_WHAT_SINGLE
:
2806 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
2807 tss
->stepping_over_breakpoint
= 1;
2808 /* Still need to check other stuff, at least the case
2809 where we are stepping and step out of the right range. */
2812 case BPSTAT_WHAT_STOP_NOISY
:
2814 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
2815 stop_print_frame
= 1;
2817 /* We are about to nuke the step_resume_breakpointt via the
2818 cleanup chain, so no need to worry about it here. */
2820 stop_stepping (ecs
);
2823 case BPSTAT_WHAT_STOP_SILENT
:
2825 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
2826 stop_print_frame
= 0;
2828 /* We are about to nuke the step_resume_breakpoin via the
2829 cleanup chain, so no need to worry about it here. */
2831 stop_stepping (ecs
);
2834 case BPSTAT_WHAT_STEP_RESUME
:
2835 /* This proably demands a more elegant solution, but, yeah
2838 This function's use of the simple variable
2839 step_resume_breakpoint doesn't seem to accomodate
2840 simultaneously active step-resume bp's, although the
2841 breakpoint list certainly can.
2843 If we reach here and step_resume_breakpoint is already
2844 NULL, then apparently we have multiple active
2845 step-resume bp's. We'll just delete the breakpoint we
2846 stopped at, and carry on.
2848 Correction: what the code currently does is delete a
2849 step-resume bp, but it makes no effort to ensure that
2850 the one deleted is the one currently stopped at. MVS */
2853 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
2855 if (step_resume_breakpoint
== NULL
)
2857 step_resume_breakpoint
=
2858 bpstat_find_step_resume_breakpoint (stop_bpstat
);
2860 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2861 if (tss
->step_after_step_resume_breakpoint
)
2863 /* Back when the step-resume breakpoint was inserted, we
2864 were trying to single-step off a breakpoint. Go back
2866 tss
->step_after_step_resume_breakpoint
= 0;
2867 tss
->stepping_over_breakpoint
= 1;
2873 case BPSTAT_WHAT_CHECK_SHLIBS
:
2874 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
:
2877 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
2879 /* Check for any newly added shared libraries if we're
2880 supposed to be adding them automatically. Switch
2881 terminal for any messages produced by
2882 breakpoint_re_set. */
2883 target_terminal_ours_for_output ();
2884 /* NOTE: cagney/2003-11-25: Make certain that the target
2885 stack's section table is kept up-to-date. Architectures,
2886 (e.g., PPC64), use the section table to perform
2887 operations such as address => section name and hence
2888 require the table to contain all sections (including
2889 those found in shared libraries). */
2890 /* NOTE: cagney/2003-11-25: Pass current_target and not
2891 exec_ops to SOLIB_ADD. This is because current GDB is
2892 only tooled to propagate section_table changes out from
2893 the "current_target" (see target_resize_to_sections), and
2894 not up from the exec stratum. This, of course, isn't
2895 right. "infrun.c" should only interact with the
2896 exec/process stratum, instead relying on the target stack
2897 to propagate relevant changes (stop, section table
2898 changed, ...) up to other layers. */
2900 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2902 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2904 target_terminal_inferior ();
2906 /* If requested, stop when the dynamic linker notifies
2907 gdb of events. This allows the user to get control
2908 and place breakpoints in initializer routines for
2909 dynamically loaded objects (among other things). */
2910 if (stop_on_solib_events
|| stop_stack_dummy
)
2912 stop_stepping (ecs
);
2916 /* If we stopped due to an explicit catchpoint, then the
2917 (see above) call to SOLIB_ADD pulled in any symbols
2918 from a newly-loaded library, if appropriate.
2920 We do want the inferior to stop, but not where it is
2921 now, which is in the dynamic linker callback. Rather,
2922 we would like it stop in the user's program, just after
2923 the call that caused this catchpoint to trigger. That
2924 gives the user a more useful vantage from which to
2925 examine their program's state. */
2926 else if (what
.main_action
2927 == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
)
2929 /* ??rehrauer: If I could figure out how to get the
2930 right return PC from here, we could just set a temp
2931 breakpoint and resume. I'm not sure we can without
2932 cracking open the dld's shared libraries and sniffing
2933 their unwind tables and text/data ranges, and that's
2934 not a terribly portable notion.
2936 Until that time, we must step the inferior out of the
2937 dld callback, and also out of the dld itself (and any
2938 code or stubs in libdld.sl, such as "shl_load" and
2939 friends) until we reach non-dld code. At that point,
2940 we can stop stepping. */
2941 bpstat_get_triggered_catchpoints (stop_bpstat
,
2943 stepping_through_solib_catchpoints
);
2944 tss
->stepping_through_solib_after_catch
= 1;
2946 /* Be sure to lift all breakpoints, so the inferior does
2947 actually step past this point... */
2948 tss
->stepping_over_breakpoint
= 1;
2953 /* We want to step over this breakpoint, then keep going. */
2954 tss
->stepping_over_breakpoint
= 1;
2960 case BPSTAT_WHAT_LAST
:
2961 /* Not a real code, but listed here to shut up gcc -Wall. */
2963 case BPSTAT_WHAT_KEEP_CHECKING
:
2968 /* We come here if we hit a breakpoint but should not
2969 stop for it. Possibly we also were stepping
2970 and should stop for that. So fall through and
2971 test for stepping. But, if not stepping,
2974 /* Are we stepping to get the inferior out of the dynamic linker's
2975 hook (and possibly the dld itself) after catching a shlib
2977 if (tss
->stepping_through_solib_after_catch
)
2979 #if defined(SOLIB_ADD)
2980 /* Have we reached our destination? If not, keep going. */
2981 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
2984 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
2985 tss
->stepping_over_breakpoint
= 1;
2991 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
2992 /* Else, stop and report the catchpoint(s) whose triggering
2993 caused us to begin stepping. */
2994 tss
->stepping_through_solib_after_catch
= 0;
2995 bpstat_clear (&stop_bpstat
);
2996 stop_bpstat
= bpstat_copy (tss
->stepping_through_solib_catchpoints
);
2997 bpstat_clear (&tss
->stepping_through_solib_catchpoints
);
2998 stop_print_frame
= 1;
2999 stop_stepping (ecs
);
3003 if (step_resume_breakpoint
)
3006 fprintf_unfiltered (gdb_stdlog
,
3007 "infrun: step-resume breakpoint is inserted\n");
3009 /* Having a step-resume breakpoint overrides anything
3010 else having to do with stepping commands until
3011 that breakpoint is reached. */
3016 if (step_range_end
== 0)
3019 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
3020 /* Likewise if we aren't even stepping. */
3025 /* If stepping through a line, keep going if still within it.
3027 Note that step_range_end is the address of the first instruction
3028 beyond the step range, and NOT the address of the last instruction
3030 if (stop_pc
>= step_range_start
&& stop_pc
< step_range_end
)
3033 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping inside range [0x%s-0x%s]\n",
3034 paddr_nz (step_range_start
),
3035 paddr_nz (step_range_end
));
3040 /* We stepped out of the stepping range. */
3042 /* If we are stepping at the source level and entered the runtime
3043 loader dynamic symbol resolution code, we keep on single stepping
3044 until we exit the run time loader code and reach the callee's
3046 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3047 && in_solib_dynsym_resolve_code (stop_pc
))
3049 CORE_ADDR pc_after_resolver
=
3050 gdbarch_skip_solib_resolver (current_gdbarch
, stop_pc
);
3053 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
3055 if (pc_after_resolver
)
3057 /* Set up a step-resume breakpoint at the address
3058 indicated by SKIP_SOLIB_RESOLVER. */
3059 struct symtab_and_line sr_sal
;
3061 sr_sal
.pc
= pc_after_resolver
;
3063 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3070 if (step_range_end
!= 1
3071 && (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3072 || step_over_calls
== STEP_OVER_ALL
)
3073 && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME
)
3076 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
3077 /* The inferior, while doing a "step" or "next", has ended up in
3078 a signal trampoline (either by a signal being delivered or by
3079 the signal handler returning). Just single-step until the
3080 inferior leaves the trampoline (either by calling the handler
3086 /* Check for subroutine calls. The check for the current frame
3087 equalling the step ID is not necessary - the check of the
3088 previous frame's ID is sufficient - but it is a common case and
3089 cheaper than checking the previous frame's ID.
3091 NOTE: frame_id_eq will never report two invalid frame IDs as
3092 being equal, so to get into this block, both the current and
3093 previous frame must have valid frame IDs. */
3094 if (!frame_id_eq (get_frame_id (get_current_frame ()), step_frame_id
)
3095 && frame_id_eq (frame_unwind_id (get_current_frame ()), step_frame_id
))
3097 CORE_ADDR real_stop_pc
;
3100 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
3102 if ((step_over_calls
== STEP_OVER_NONE
)
3103 || ((step_range_end
== 1)
3104 && in_prologue (prev_pc
, ecs
->stop_func_start
)))
3106 /* I presume that step_over_calls is only 0 when we're
3107 supposed to be stepping at the assembly language level
3108 ("stepi"). Just stop. */
3109 /* Also, maybe we just did a "nexti" inside a prolog, so we
3110 thought it was a subroutine call but it was not. Stop as
3113 print_stop_reason (END_STEPPING_RANGE
, 0);
3114 stop_stepping (ecs
);
3118 if (step_over_calls
== STEP_OVER_ALL
)
3120 /* We're doing a "next", set a breakpoint at callee's return
3121 address (the address at which the caller will
3123 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3128 /* If we are in a function call trampoline (a stub between the
3129 calling routine and the real function), locate the real
3130 function. That's what tells us (a) whether we want to step
3131 into it at all, and (b) what prologue we want to run to the
3132 end of, if we do step into it. */
3133 real_stop_pc
= skip_language_trampoline (get_current_frame (), stop_pc
);
3134 if (real_stop_pc
== 0)
3135 real_stop_pc
= gdbarch_skip_trampoline_code
3136 (current_gdbarch
, get_current_frame (), stop_pc
);
3137 if (real_stop_pc
!= 0)
3138 ecs
->stop_func_start
= real_stop_pc
;
3140 if (in_solib_dynsym_resolve_code (ecs
->stop_func_start
))
3142 struct symtab_and_line sr_sal
;
3144 sr_sal
.pc
= ecs
->stop_func_start
;
3146 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3151 /* If we have line number information for the function we are
3152 thinking of stepping into, step into it.
3154 If there are several symtabs at that PC (e.g. with include
3155 files), just want to know whether *any* of them have line
3156 numbers. find_pc_line handles this. */
3158 struct symtab_and_line tmp_sal
;
3160 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3161 if (tmp_sal
.line
!= 0)
3163 step_into_function (ecs
);
3168 /* If we have no line number and the step-stop-if-no-debug is
3169 set, we stop the step so that the user has a chance to switch
3170 in assembly mode. */
3171 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
&& step_stop_if_no_debug
)
3174 print_stop_reason (END_STEPPING_RANGE
, 0);
3175 stop_stepping (ecs
);
3179 /* Set a breakpoint at callee's return address (the address at
3180 which the caller will resume). */
3181 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3186 /* If we're in the return path from a shared library trampoline,
3187 we want to proceed through the trampoline when stepping. */
3188 if (gdbarch_in_solib_return_trampoline (current_gdbarch
,
3189 stop_pc
, ecs
->stop_func_name
))
3191 /* Determine where this trampoline returns. */
3192 CORE_ADDR real_stop_pc
;
3193 real_stop_pc
= gdbarch_skip_trampoline_code
3194 (current_gdbarch
, get_current_frame (), stop_pc
);
3197 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
3199 /* Only proceed through if we know where it's going. */
3202 /* And put the step-breakpoint there and go until there. */
3203 struct symtab_and_line sr_sal
;
3205 init_sal (&sr_sal
); /* initialize to zeroes */
3206 sr_sal
.pc
= real_stop_pc
;
3207 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3209 /* Do not specify what the fp should be when we stop since
3210 on some machines the prologue is where the new fp value
3212 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3214 /* Restart without fiddling with the step ranges or
3221 stop_pc_sal
= find_pc_line (stop_pc
, 0);
3223 /* NOTE: tausq/2004-05-24: This if block used to be done before all
3224 the trampoline processing logic, however, there are some trampolines
3225 that have no names, so we should do trampoline handling first. */
3226 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3227 && ecs
->stop_func_name
== NULL
3228 && stop_pc_sal
.line
== 0)
3231 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
3233 /* The inferior just stepped into, or returned to, an
3234 undebuggable function (where there is no debugging information
3235 and no line number corresponding to the address where the
3236 inferior stopped). Since we want to skip this kind of code,
3237 we keep going until the inferior returns from this
3238 function - unless the user has asked us not to (via
3239 set step-mode) or we no longer know how to get back
3240 to the call site. */
3241 if (step_stop_if_no_debug
3242 || !frame_id_p (frame_unwind_id (get_current_frame ())))
3244 /* If we have no line number and the step-stop-if-no-debug
3245 is set, we stop the step so that the user has a chance to
3246 switch in assembly mode. */
3248 print_stop_reason (END_STEPPING_RANGE
, 0);
3249 stop_stepping (ecs
);
3254 /* Set a breakpoint at callee's return address (the address
3255 at which the caller will resume). */
3256 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3262 if (step_range_end
== 1)
3264 /* It is stepi or nexti. We always want to stop stepping after
3267 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
3269 print_stop_reason (END_STEPPING_RANGE
, 0);
3270 stop_stepping (ecs
);
3274 if (stop_pc_sal
.line
== 0)
3276 /* We have no line number information. That means to stop
3277 stepping (does this always happen right after one instruction,
3278 when we do "s" in a function with no line numbers,
3279 or can this happen as a result of a return or longjmp?). */
3281 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
3283 print_stop_reason (END_STEPPING_RANGE
, 0);
3284 stop_stepping (ecs
);
3288 if ((stop_pc
== stop_pc_sal
.pc
)
3289 && (tss
->current_line
!= stop_pc_sal
.line
3290 || tss
->current_symtab
!= stop_pc_sal
.symtab
))
3292 /* We are at the start of a different line. So stop. Note that
3293 we don't stop if we step into the middle of a different line.
3294 That is said to make things like for (;;) statements work
3297 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
3299 print_stop_reason (END_STEPPING_RANGE
, 0);
3300 stop_stepping (ecs
);
3304 /* We aren't done stepping.
3306 Optimize by setting the stepping range to the line.
3307 (We might not be in the original line, but if we entered a
3308 new line in mid-statement, we continue stepping. This makes
3309 things like for(;;) statements work better.) */
3311 step_range_start
= stop_pc_sal
.pc
;
3312 step_range_end
= stop_pc_sal
.end
;
3313 step_frame_id
= get_frame_id (get_current_frame ());
3314 tss
->current_line
= stop_pc_sal
.line
;
3315 tss
->current_symtab
= stop_pc_sal
.symtab
;
3317 /* In the case where we just stepped out of a function into the
3318 middle of a line of the caller, continue stepping, but
3319 step_frame_id must be modified to current frame */
3321 /* NOTE: cagney/2003-10-16: I think this frame ID inner test is too
3322 generous. It will trigger on things like a step into a frameless
3323 stackless leaf function. I think the logic should instead look
3324 at the unwound frame ID has that should give a more robust
3325 indication of what happened. */
3326 if (step
- ID
== current
- ID
)
3327 still stepping in same function
;
3328 else if (step
- ID
== unwind (current
- ID
))
3329 stepped into a function
;
3331 stepped out of a function
;
3332 /* Of course this assumes that the frame ID unwind code is robust
3333 and we're willing to introduce frame unwind logic into this
3334 function. Fortunately, those days are nearly upon us. */
3337 struct frame_info
*frame
= get_current_frame ();
3338 struct frame_id current_frame
= get_frame_id (frame
);
3339 if (!(frame_id_inner (get_frame_arch (frame
), current_frame
,
3341 step_frame_id
= current_frame
;
3345 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
3349 /* Are we in the middle of stepping? */
3352 currently_stepping (struct thread_stepping_state
*tss
)
3354 return (((step_range_end
&& step_resume_breakpoint
== NULL
)
3355 || stepping_over_breakpoint
)
3356 || tss
->stepping_through_solib_after_catch
3357 || bpstat_should_step ());
3360 /* Subroutine call with source code we should not step over. Do step
3361 to the first line of code in it. */
3364 step_into_function (struct execution_control_state
*ecs
)
3367 struct symtab_and_line stop_func_sal
, sr_sal
;
3369 s
= find_pc_symtab (stop_pc
);
3370 if (s
&& s
->language
!= language_asm
)
3371 ecs
->stop_func_start
= gdbarch_skip_prologue
3372 (current_gdbarch
, ecs
->stop_func_start
);
3374 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3375 /* Use the step_resume_break to step until the end of the prologue,
3376 even if that involves jumps (as it seems to on the vax under
3378 /* If the prologue ends in the middle of a source line, continue to
3379 the end of that source line (if it is still within the function).
3380 Otherwise, just go to end of prologue. */
3381 if (stop_func_sal
.end
3382 && stop_func_sal
.pc
!= ecs
->stop_func_start
3383 && stop_func_sal
.end
< ecs
->stop_func_end
)
3384 ecs
->stop_func_start
= stop_func_sal
.end
;
3386 /* Architectures which require breakpoint adjustment might not be able
3387 to place a breakpoint at the computed address. If so, the test
3388 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
3389 ecs->stop_func_start to an address at which a breakpoint may be
3390 legitimately placed.
3392 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
3393 made, GDB will enter an infinite loop when stepping through
3394 optimized code consisting of VLIW instructions which contain
3395 subinstructions corresponding to different source lines. On
3396 FR-V, it's not permitted to place a breakpoint on any but the
3397 first subinstruction of a VLIW instruction. When a breakpoint is
3398 set, GDB will adjust the breakpoint address to the beginning of
3399 the VLIW instruction. Thus, we need to make the corresponding
3400 adjustment here when computing the stop address. */
3402 if (gdbarch_adjust_breakpoint_address_p (current_gdbarch
))
3404 ecs
->stop_func_start
3405 = gdbarch_adjust_breakpoint_address (current_gdbarch
,
3406 ecs
->stop_func_start
);
3409 if (ecs
->stop_func_start
== stop_pc
)
3411 /* We are already there: stop now. */
3413 print_stop_reason (END_STEPPING_RANGE
, 0);
3414 stop_stepping (ecs
);
3419 /* Put the step-breakpoint there and go until there. */
3420 init_sal (&sr_sal
); /* initialize to zeroes */
3421 sr_sal
.pc
= ecs
->stop_func_start
;
3422 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
3424 /* Do not specify what the fp should be when we stop since on
3425 some machines the prologue is where the new fp value is
3427 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3429 /* And make sure stepping stops right away then. */
3430 step_range_end
= step_range_start
;
3435 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
3436 This is used to both functions and to skip over code. */
3439 insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
3440 struct frame_id sr_id
)
3442 /* There should never be more than one step-resume or longjmp-resume
3443 breakpoint per thread, so we should never be setting a new
3444 step_resume_breakpoint when one is already active. */
3445 gdb_assert (step_resume_breakpoint
== NULL
);
3448 fprintf_unfiltered (gdb_stdlog
,
3449 "infrun: inserting step-resume breakpoint at 0x%s\n",
3450 paddr_nz (sr_sal
.pc
));
3452 step_resume_breakpoint
= set_momentary_breakpoint (sr_sal
, sr_id
,
3456 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
3457 to skip a potential signal handler.
3459 This is called with the interrupted function's frame. The signal
3460 handler, when it returns, will resume the interrupted function at
3464 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
3466 struct symtab_and_line sr_sal
;
3468 gdb_assert (return_frame
!= NULL
);
3469 init_sal (&sr_sal
); /* initialize to zeros */
3471 sr_sal
.pc
= gdbarch_addr_bits_remove
3472 (current_gdbarch
, get_frame_pc (return_frame
));
3473 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3475 insert_step_resume_breakpoint_at_sal (sr_sal
, get_frame_id (return_frame
));
3478 /* Similar to insert_step_resume_breakpoint_at_frame, except
3479 but a breakpoint at the previous frame's PC. This is used to
3480 skip a function after stepping into it (for "next" or if the called
3481 function has no debugging information).
3483 The current function has almost always been reached by single
3484 stepping a call or return instruction. NEXT_FRAME belongs to the
3485 current function, and the breakpoint will be set at the caller's
3488 This is a separate function rather than reusing
3489 insert_step_resume_breakpoint_at_frame in order to avoid
3490 get_prev_frame, which may stop prematurely (see the implementation
3491 of frame_unwind_id for an example). */
3494 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
3496 struct symtab_and_line sr_sal
;
3498 /* We shouldn't have gotten here if we don't know where the call site
3500 gdb_assert (frame_id_p (frame_unwind_id (next_frame
)));
3502 init_sal (&sr_sal
); /* initialize to zeros */
3504 sr_sal
.pc
= gdbarch_addr_bits_remove
3505 (current_gdbarch
, frame_pc_unwind (next_frame
));
3506 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3508 insert_step_resume_breakpoint_at_sal (sr_sal
, frame_unwind_id (next_frame
));
3511 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
3512 new breakpoint at the target of a jmp_buf. The handling of
3513 longjmp-resume uses the same mechanisms used for handling
3514 "step-resume" breakpoints. */
3517 insert_longjmp_resume_breakpoint (CORE_ADDR pc
)
3519 /* There should never be more than one step-resume or longjmp-resume
3520 breakpoint per thread, so we should never be setting a new
3521 longjmp_resume_breakpoint when one is already active. */
3522 gdb_assert (step_resume_breakpoint
== NULL
);
3525 fprintf_unfiltered (gdb_stdlog
,
3526 "infrun: inserting longjmp-resume breakpoint at 0x%s\n",
3529 step_resume_breakpoint
=
3530 set_momentary_breakpoint_at_pc (pc
, bp_longjmp_resume
);
3534 stop_stepping (struct execution_control_state
*ecs
)
3537 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
3539 /* Let callers know we don't want to wait for the inferior anymore. */
3540 ecs
->wait_some_more
= 0;
3543 /* This function handles various cases where we need to continue
3544 waiting for the inferior. */
3545 /* (Used to be the keep_going: label in the old wait_for_inferior) */
3548 keep_going (struct execution_control_state
*ecs
)
3550 /* Save the pc before execution, to compare with pc after stop. */
3551 prev_pc
= read_pc (); /* Might have been DECR_AFTER_BREAK */
3553 /* If we did not do break;, it means we should keep running the
3554 inferior and not return to debugger. */
3556 if (stepping_over_breakpoint
&& stop_signal
!= TARGET_SIGNAL_TRAP
)
3558 /* We took a signal (which we are supposed to pass through to
3559 the inferior, else we'd have done a break above) and we
3560 haven't yet gotten our trap. Simply continue. */
3561 resume (currently_stepping (tss
), stop_signal
);
3565 /* Either the trap was not expected, but we are continuing
3566 anyway (the user asked that this signal be passed to the
3569 The signal was SIGTRAP, e.g. it was our signal, but we
3570 decided we should resume from it.
3572 We're going to run this baby now!
3574 Note that insert_breakpoints won't try to re-insert
3575 already inserted breakpoints. Therefore, we don't
3576 care if breakpoints were already inserted, or not. */
3578 if (tss
->stepping_over_breakpoint
)
3580 if (! use_displaced_stepping (current_gdbarch
))
3581 /* Since we can't do a displaced step, we have to remove
3582 the breakpoint while we step it. To keep things
3583 simple, we remove them all. */
3584 remove_breakpoints ();
3588 struct gdb_exception e
;
3589 /* Stop stepping when inserting breakpoints
3591 TRY_CATCH (e
, RETURN_MASK_ERROR
)
3593 insert_breakpoints ();
3597 stop_stepping (ecs
);
3602 stepping_over_breakpoint
= tss
->stepping_over_breakpoint
;
3604 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3605 specifies that such a signal should be delivered to the
3608 Typically, this would occure when a user is debugging a
3609 target monitor on a simulator: the target monitor sets a
3610 breakpoint; the simulator encounters this break-point and
3611 halts the simulation handing control to GDB; GDB, noteing
3612 that the break-point isn't valid, returns control back to the
3613 simulator; the simulator then delivers the hardware
3614 equivalent of a SIGNAL_TRAP to the program being debugged. */
3616 if (stop_signal
== TARGET_SIGNAL_TRAP
&& !signal_program
[stop_signal
])
3617 stop_signal
= TARGET_SIGNAL_0
;
3620 resume (currently_stepping (tss
), stop_signal
);
3623 prepare_to_wait (ecs
);
3626 /* This function normally comes after a resume, before
3627 handle_inferior_event exits. It takes care of any last bits of
3628 housekeeping, and sets the all-important wait_some_more flag. */
3631 prepare_to_wait (struct execution_control_state
*ecs
)
3634 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
3635 if (infwait_state
== infwait_normal_state
)
3637 overlay_cache_invalid
= 1;
3639 /* We have to invalidate the registers BEFORE calling
3640 target_wait because they can be loaded from the target while
3641 in target_wait. This makes remote debugging a bit more
3642 efficient for those targets that provide critical registers
3643 as part of their normal status mechanism. */
3645 registers_changed ();
3646 waiton_ptid
= pid_to_ptid (-1);
3648 /* This is the old end of the while loop. Let everybody know we
3649 want to wait for the inferior some more and get called again
3651 ecs
->wait_some_more
= 1;
3654 /* Print why the inferior has stopped. We always print something when
3655 the inferior exits, or receives a signal. The rest of the cases are
3656 dealt with later on in normal_stop() and print_it_typical(). Ideally
3657 there should be a call to this function from handle_inferior_event()
3658 each time stop_stepping() is called.*/
3660 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
3662 switch (stop_reason
)
3664 case END_STEPPING_RANGE
:
3665 /* We are done with a step/next/si/ni command. */
3666 /* For now print nothing. */
3667 /* Print a message only if not in the middle of doing a "step n"
3668 operation for n > 1 */
3669 if (!step_multi
|| !stop_step
)
3670 if (ui_out_is_mi_like_p (uiout
))
3673 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
3676 /* The inferior was terminated by a signal. */
3677 annotate_signalled ();
3678 if (ui_out_is_mi_like_p (uiout
))
3681 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
3682 ui_out_text (uiout
, "\nProgram terminated with signal ");
3683 annotate_signal_name ();
3684 ui_out_field_string (uiout
, "signal-name",
3685 target_signal_to_name (stop_info
));
3686 annotate_signal_name_end ();
3687 ui_out_text (uiout
, ", ");
3688 annotate_signal_string ();
3689 ui_out_field_string (uiout
, "signal-meaning",
3690 target_signal_to_string (stop_info
));
3691 annotate_signal_string_end ();
3692 ui_out_text (uiout
, ".\n");
3693 ui_out_text (uiout
, "The program no longer exists.\n");
3696 /* The inferior program is finished. */
3697 annotate_exited (stop_info
);
3700 if (ui_out_is_mi_like_p (uiout
))
3701 ui_out_field_string (uiout
, "reason",
3702 async_reason_lookup (EXEC_ASYNC_EXITED
));
3703 ui_out_text (uiout
, "\nProgram exited with code ");
3704 ui_out_field_fmt (uiout
, "exit-code", "0%o",
3705 (unsigned int) stop_info
);
3706 ui_out_text (uiout
, ".\n");
3710 if (ui_out_is_mi_like_p (uiout
))
3713 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
3714 ui_out_text (uiout
, "\nProgram exited normally.\n");
3716 /* Support the --return-child-result option. */
3717 return_child_result_value
= stop_info
;
3719 case SIGNAL_RECEIVED
:
3720 /* Signal received. The signal table tells us to print about
3723 ui_out_text (uiout
, "\nProgram received signal ");
3724 annotate_signal_name ();
3725 if (ui_out_is_mi_like_p (uiout
))
3727 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
3728 ui_out_field_string (uiout
, "signal-name",
3729 target_signal_to_name (stop_info
));
3730 annotate_signal_name_end ();
3731 ui_out_text (uiout
, ", ");
3732 annotate_signal_string ();
3733 ui_out_field_string (uiout
, "signal-meaning",
3734 target_signal_to_string (stop_info
));
3735 annotate_signal_string_end ();
3736 ui_out_text (uiout
, ".\n");
3739 internal_error (__FILE__
, __LINE__
,
3740 _("print_stop_reason: unrecognized enum value"));
3746 /* Here to return control to GDB when the inferior stops for real.
3747 Print appropriate messages, remove breakpoints, give terminal our modes.
3749 STOP_PRINT_FRAME nonzero means print the executing frame
3750 (pc, function, args, file, line number and line text).
3751 BREAKPOINTS_FAILED nonzero means stop was due to error
3752 attempting to insert breakpoints. */
3757 struct target_waitstatus last
;
3760 get_last_target_status (&last_ptid
, &last
);
3762 /* In non-stop mode, we don't want GDB to switch threads behind the
3763 user's back, to avoid races where the user is typing a command to
3764 apply to thread x, but GDB switches to thread y before the user
3765 finishes entering the command. */
3767 /* As with the notification of thread events, we want to delay
3768 notifying the user that we've switched thread context until
3769 the inferior actually stops.
3771 There's no point in saying anything if the inferior has exited.
3772 Note that SIGNALLED here means "exited with a signal", not
3773 "received a signal". */
3775 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
3776 && target_has_execution
3777 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3778 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3780 target_terminal_ours_for_output ();
3781 printf_filtered (_("[Switching to %s]\n"),
3782 target_pid_to_str (inferior_ptid
));
3783 annotate_thread_changed ();
3784 previous_inferior_ptid
= inferior_ptid
;
3787 /* NOTE drow/2004-01-17: Is this still necessary? */
3788 /* Make sure that the current_frame's pc is correct. This
3789 is a correction for setting up the frame info before doing
3790 gdbarch_decr_pc_after_break */
3791 if (target_has_execution
)
3792 /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
3793 gdbarch_decr_pc_after_break, the program counter can change. Ask the
3794 frame code to check for this and sort out any resultant mess.
3795 gdbarch_decr_pc_after_break needs to just go away. */
3796 deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
3798 if (!breakpoints_always_inserted_mode () && target_has_execution
)
3800 if (remove_breakpoints ())
3802 target_terminal_ours_for_output ();
3803 printf_filtered (_("\
3804 Cannot remove breakpoints because program is no longer writable.\n\
3805 It might be running in another process.\n\
3806 Further execution is probably impossible.\n"));
3810 /* If an auto-display called a function and that got a signal,
3811 delete that auto-display to avoid an infinite recursion. */
3813 if (stopped_by_random_signal
)
3814 disable_current_display ();
3816 /* Don't print a message if in the middle of doing a "step n"
3817 operation for n > 1 */
3818 if (step_multi
&& stop_step
)
3821 target_terminal_ours ();
3823 /* Set the current source location. This will also happen if we
3824 display the frame below, but the current SAL will be incorrect
3825 during a user hook-stop function. */
3826 if (target_has_stack
&& !stop_stack_dummy
)
3827 set_current_sal_from_frame (get_current_frame (), 1);
3829 /* Look up the hook_stop and run it (CLI internally handles problem
3830 of stop_command's pre-hook not existing). */
3832 catch_errors (hook_stop_stub
, stop_command
,
3833 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
3835 if (!target_has_stack
)
3841 /* Select innermost stack frame - i.e., current frame is frame 0,
3842 and current location is based on that.
3843 Don't do this on return from a stack dummy routine,
3844 or if the program has exited. */
3846 if (!stop_stack_dummy
)
3848 select_frame (get_current_frame ());
3850 /* Print current location without a level number, if
3851 we have changed functions or hit a breakpoint.
3852 Print source line if we have one.
3853 bpstat_print() contains the logic deciding in detail
3854 what to print, based on the event(s) that just occurred. */
3856 /* If --batch-silent is enabled then there's no need to print the current
3857 source location, and to try risks causing an error message about
3858 missing source files. */
3859 if (stop_print_frame
&& !batch_silent
)
3863 int do_frame_printing
= 1;
3865 bpstat_ret
= bpstat_print (stop_bpstat
);
3869 /* If we had hit a shared library event breakpoint,
3870 bpstat_print would print out this message. If we hit
3871 an OS-level shared library event, do the same
3873 if (last
.kind
== TARGET_WAITKIND_LOADED
)
3875 printf_filtered (_("Stopped due to shared library event\n"));
3876 source_flag
= SRC_LINE
; /* something bogus */
3877 do_frame_printing
= 0;
3881 /* FIXME: cagney/2002-12-01: Given that a frame ID does
3882 (or should) carry around the function and does (or
3883 should) use that when doing a frame comparison. */
3885 && frame_id_eq (step_frame_id
,
3886 get_frame_id (get_current_frame ()))
3887 && step_start_function
== find_pc_function (stop_pc
))
3888 source_flag
= SRC_LINE
; /* finished step, just print source line */
3890 source_flag
= SRC_AND_LOC
; /* print location and source line */
3892 case PRINT_SRC_AND_LOC
:
3893 source_flag
= SRC_AND_LOC
; /* print location and source line */
3895 case PRINT_SRC_ONLY
:
3896 source_flag
= SRC_LINE
;
3899 source_flag
= SRC_LINE
; /* something bogus */
3900 do_frame_printing
= 0;
3903 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
3906 if (ui_out_is_mi_like_p (uiout
))
3909 ui_out_field_int (uiout
, "thread-id",
3910 pid_to_thread_id (inferior_ptid
));
3913 struct cleanup
*back_to
= make_cleanup_ui_out_list_begin_end
3914 (uiout
, "stopped-threads");
3915 ui_out_field_int (uiout
, NULL
,
3916 pid_to_thread_id (inferior_ptid
));
3917 do_cleanups (back_to
);
3920 ui_out_field_string (uiout
, "stopped-threads", "all");
3922 /* The behavior of this routine with respect to the source
3924 SRC_LINE: Print only source line
3925 LOCATION: Print only location
3926 SRC_AND_LOC: Print location and source line */
3927 if (do_frame_printing
)
3928 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
3930 /* Display the auto-display expressions. */
3935 /* Save the function value return registers, if we care.
3936 We might be about to restore their previous contents. */
3937 if (proceed_to_finish
)
3939 /* This should not be necessary. */
3941 regcache_xfree (stop_registers
);
3943 /* NB: The copy goes through to the target picking up the value of
3944 all the registers. */
3945 stop_registers
= regcache_dup (get_current_regcache ());
3948 if (stop_stack_dummy
)
3950 /* Pop the empty frame that contains the stack dummy. POP_FRAME
3951 ends with a setting of the current frame, so we can use that
3953 frame_pop (get_current_frame ());
3954 /* Set stop_pc to what it was before we called the function.
3955 Can't rely on restore_inferior_status because that only gets
3956 called if we don't stop in the called function. */
3957 stop_pc
= read_pc ();
3958 select_frame (get_current_frame ());
3962 annotate_stopped ();
3963 if (!suppress_stop_observer
&& !step_multi
)
3964 observer_notify_normal_stop (stop_bpstat
);
3965 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3966 Delete any breakpoint that is to be deleted at the next stop. */
3967 breakpoint_auto_delete (stop_bpstat
);
3969 if (target_has_execution
3970 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3971 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3974 set_running (pid_to_ptid (-1), 0);
3976 set_running (inferior_ptid
, 0);
3981 hook_stop_stub (void *cmd
)
3983 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
3988 signal_stop_state (int signo
)
3990 /* Always stop on signals if we're just gaining control of the
3992 return signal_stop
[signo
] || stop_soon
!= NO_STOP_QUIETLY
;
3996 signal_print_state (int signo
)
3998 return signal_print
[signo
];
4002 signal_pass_state (int signo
)
4004 return signal_program
[signo
];
4008 signal_stop_update (int signo
, int state
)
4010 int ret
= signal_stop
[signo
];
4011 signal_stop
[signo
] = state
;
4016 signal_print_update (int signo
, int state
)
4018 int ret
= signal_print
[signo
];
4019 signal_print
[signo
] = state
;
4024 signal_pass_update (int signo
, int state
)
4026 int ret
= signal_program
[signo
];
4027 signal_program
[signo
] = state
;
4032 sig_print_header (void)
4034 printf_filtered (_("\
4035 Signal Stop\tPrint\tPass to program\tDescription\n"));
4039 sig_print_info (enum target_signal oursig
)
4041 char *name
= target_signal_to_name (oursig
);
4042 int name_padding
= 13 - strlen (name
);
4044 if (name_padding
<= 0)
4047 printf_filtered ("%s", name
);
4048 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
4049 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
4050 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
4051 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
4052 printf_filtered ("%s\n", target_signal_to_string (oursig
));
4055 /* Specify how various signals in the inferior should be handled. */
4058 handle_command (char *args
, int from_tty
)
4061 int digits
, wordlen
;
4062 int sigfirst
, signum
, siglast
;
4063 enum target_signal oursig
;
4066 unsigned char *sigs
;
4067 struct cleanup
*old_chain
;
4071 error_no_arg (_("signal to handle"));
4074 /* Allocate and zero an array of flags for which signals to handle. */
4076 nsigs
= (int) TARGET_SIGNAL_LAST
;
4077 sigs
= (unsigned char *) alloca (nsigs
);
4078 memset (sigs
, 0, nsigs
);
4080 /* Break the command line up into args. */
4082 argv
= buildargv (args
);
4087 old_chain
= make_cleanup_freeargv (argv
);
4089 /* Walk through the args, looking for signal oursigs, signal names, and
4090 actions. Signal numbers and signal names may be interspersed with
4091 actions, with the actions being performed for all signals cumulatively
4092 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
4094 while (*argv
!= NULL
)
4096 wordlen
= strlen (*argv
);
4097 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
4101 sigfirst
= siglast
= -1;
4103 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
4105 /* Apply action to all signals except those used by the
4106 debugger. Silently skip those. */
4109 siglast
= nsigs
- 1;
4111 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
4113 SET_SIGS (nsigs
, sigs
, signal_stop
);
4114 SET_SIGS (nsigs
, sigs
, signal_print
);
4116 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
4118 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4120 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
4122 SET_SIGS (nsigs
, sigs
, signal_print
);
4124 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
4126 SET_SIGS (nsigs
, sigs
, signal_program
);
4128 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
4130 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4132 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
4134 SET_SIGS (nsigs
, sigs
, signal_program
);
4136 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
4138 UNSET_SIGS (nsigs
, sigs
, signal_print
);
4139 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4141 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
4143 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4145 else if (digits
> 0)
4147 /* It is numeric. The numeric signal refers to our own
4148 internal signal numbering from target.h, not to host/target
4149 signal number. This is a feature; users really should be
4150 using symbolic names anyway, and the common ones like
4151 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
4153 sigfirst
= siglast
= (int)
4154 target_signal_from_command (atoi (*argv
));
4155 if ((*argv
)[digits
] == '-')
4158 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
4160 if (sigfirst
> siglast
)
4162 /* Bet he didn't figure we'd think of this case... */
4170 oursig
= target_signal_from_name (*argv
);
4171 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
4173 sigfirst
= siglast
= (int) oursig
;
4177 /* Not a number and not a recognized flag word => complain. */
4178 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
4182 /* If any signal numbers or symbol names were found, set flags for
4183 which signals to apply actions to. */
4185 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
4187 switch ((enum target_signal
) signum
)
4189 case TARGET_SIGNAL_TRAP
:
4190 case TARGET_SIGNAL_INT
:
4191 if (!allsigs
&& !sigs
[signum
])
4193 if (query ("%s is used by the debugger.\n\
4194 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal
) signum
)))
4200 printf_unfiltered (_("Not confirmed, unchanged.\n"));
4201 gdb_flush (gdb_stdout
);
4205 case TARGET_SIGNAL_0
:
4206 case TARGET_SIGNAL_DEFAULT
:
4207 case TARGET_SIGNAL_UNKNOWN
:
4208 /* Make sure that "all" doesn't print these. */
4219 target_notice_signals (inferior_ptid
);
4223 /* Show the results. */
4224 sig_print_header ();
4225 for (signum
= 0; signum
< nsigs
; signum
++)
4229 sig_print_info (signum
);
4234 do_cleanups (old_chain
);
4238 xdb_handle_command (char *args
, int from_tty
)
4241 struct cleanup
*old_chain
;
4243 /* Break the command line up into args. */
4245 argv
= buildargv (args
);
4250 old_chain
= make_cleanup_freeargv (argv
);
4251 if (argv
[1] != (char *) NULL
)
4256 bufLen
= strlen (argv
[0]) + 20;
4257 argBuf
= (char *) xmalloc (bufLen
);
4261 enum target_signal oursig
;
4263 oursig
= target_signal_from_name (argv
[0]);
4264 memset (argBuf
, 0, bufLen
);
4265 if (strcmp (argv
[1], "Q") == 0)
4266 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4269 if (strcmp (argv
[1], "s") == 0)
4271 if (!signal_stop
[oursig
])
4272 sprintf (argBuf
, "%s %s", argv
[0], "stop");
4274 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
4276 else if (strcmp (argv
[1], "i") == 0)
4278 if (!signal_program
[oursig
])
4279 sprintf (argBuf
, "%s %s", argv
[0], "pass");
4281 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
4283 else if (strcmp (argv
[1], "r") == 0)
4285 if (!signal_print
[oursig
])
4286 sprintf (argBuf
, "%s %s", argv
[0], "print");
4288 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4294 handle_command (argBuf
, from_tty
);
4296 printf_filtered (_("Invalid signal handling flag.\n"));
4301 do_cleanups (old_chain
);
4304 /* Print current contents of the tables set by the handle command.
4305 It is possible we should just be printing signals actually used
4306 by the current target (but for things to work right when switching
4307 targets, all signals should be in the signal tables). */
4310 signals_info (char *signum_exp
, int from_tty
)
4312 enum target_signal oursig
;
4313 sig_print_header ();
4317 /* First see if this is a symbol name. */
4318 oursig
= target_signal_from_name (signum_exp
);
4319 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
4321 /* No, try numeric. */
4323 target_signal_from_command (parse_and_eval_long (signum_exp
));
4325 sig_print_info (oursig
);
4329 printf_filtered ("\n");
4330 /* These ugly casts brought to you by the native VAX compiler. */
4331 for (oursig
= TARGET_SIGNAL_FIRST
;
4332 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
4333 oursig
= (enum target_signal
) ((int) oursig
+ 1))
4337 if (oursig
!= TARGET_SIGNAL_UNKNOWN
4338 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
4339 sig_print_info (oursig
);
4342 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
4345 struct inferior_status
4347 enum target_signal stop_signal
;
4351 int stop_stack_dummy
;
4352 int stopped_by_random_signal
;
4353 int stepping_over_breakpoint
;
4354 CORE_ADDR step_range_start
;
4355 CORE_ADDR step_range_end
;
4356 struct frame_id step_frame_id
;
4357 enum step_over_calls_kind step_over_calls
;
4358 CORE_ADDR step_resume_break_address
;
4359 int stop_after_trap
;
4362 /* These are here because if call_function_by_hand has written some
4363 registers and then decides to call error(), we better not have changed
4365 struct regcache
*registers
;
4367 /* A frame unique identifier. */
4368 struct frame_id selected_frame_id
;
4370 int breakpoint_proceeded
;
4371 int restore_stack_info
;
4372 int proceed_to_finish
;
4376 write_inferior_status_register (struct inferior_status
*inf_status
, int regno
,
4379 int size
= register_size (current_gdbarch
, regno
);
4380 void *buf
= alloca (size
);
4381 store_signed_integer (buf
, size
, val
);
4382 regcache_raw_write (inf_status
->registers
, regno
, buf
);
4385 /* Save all of the information associated with the inferior<==>gdb
4386 connection. INF_STATUS is a pointer to a "struct inferior_status"
4387 (defined in inferior.h). */
4389 struct inferior_status
*
4390 save_inferior_status (int restore_stack_info
)
4392 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
4394 inf_status
->stop_signal
= stop_signal
;
4395 inf_status
->stop_pc
= stop_pc
;
4396 inf_status
->stop_step
= stop_step
;
4397 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
4398 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
4399 inf_status
->stepping_over_breakpoint
= stepping_over_breakpoint
;
4400 inf_status
->step_range_start
= step_range_start
;
4401 inf_status
->step_range_end
= step_range_end
;
4402 inf_status
->step_frame_id
= step_frame_id
;
4403 inf_status
->step_over_calls
= step_over_calls
;
4404 inf_status
->stop_after_trap
= stop_after_trap
;
4405 inf_status
->stop_soon
= stop_soon
;
4406 /* Save original bpstat chain here; replace it with copy of chain.
4407 If caller's caller is walking the chain, they'll be happier if we
4408 hand them back the original chain when restore_inferior_status is
4410 inf_status
->stop_bpstat
= stop_bpstat
;
4411 stop_bpstat
= bpstat_copy (stop_bpstat
);
4412 inf_status
->breakpoint_proceeded
= breakpoint_proceeded
;
4413 inf_status
->restore_stack_info
= restore_stack_info
;
4414 inf_status
->proceed_to_finish
= proceed_to_finish
;
4416 inf_status
->registers
= regcache_dup (get_current_regcache ());
4418 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
4423 restore_selected_frame (void *args
)
4425 struct frame_id
*fid
= (struct frame_id
*) args
;
4426 struct frame_info
*frame
;
4428 frame
= frame_find_by_id (*fid
);
4430 /* If inf_status->selected_frame_id is NULL, there was no previously
4434 warning (_("Unable to restore previously selected frame."));
4438 select_frame (frame
);
4444 restore_inferior_status (struct inferior_status
*inf_status
)
4446 stop_signal
= inf_status
->stop_signal
;
4447 stop_pc
= inf_status
->stop_pc
;
4448 stop_step
= inf_status
->stop_step
;
4449 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
4450 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
4451 stepping_over_breakpoint
= inf_status
->stepping_over_breakpoint
;
4452 step_range_start
= inf_status
->step_range_start
;
4453 step_range_end
= inf_status
->step_range_end
;
4454 step_frame_id
= inf_status
->step_frame_id
;
4455 step_over_calls
= inf_status
->step_over_calls
;
4456 stop_after_trap
= inf_status
->stop_after_trap
;
4457 stop_soon
= inf_status
->stop_soon
;
4458 bpstat_clear (&stop_bpstat
);
4459 stop_bpstat
= inf_status
->stop_bpstat
;
4460 breakpoint_proceeded
= inf_status
->breakpoint_proceeded
;
4461 proceed_to_finish
= inf_status
->proceed_to_finish
;
4463 /* The inferior can be gone if the user types "print exit(0)"
4464 (and perhaps other times). */
4465 if (target_has_execution
)
4466 /* NB: The register write goes through to the target. */
4467 regcache_cpy (get_current_regcache (), inf_status
->registers
);
4468 regcache_xfree (inf_status
->registers
);
4470 /* FIXME: If we are being called after stopping in a function which
4471 is called from gdb, we should not be trying to restore the
4472 selected frame; it just prints a spurious error message (The
4473 message is useful, however, in detecting bugs in gdb (like if gdb
4474 clobbers the stack)). In fact, should we be restoring the
4475 inferior status at all in that case? . */
4477 if (target_has_stack
&& inf_status
->restore_stack_info
)
4479 /* The point of catch_errors is that if the stack is clobbered,
4480 walking the stack might encounter a garbage pointer and
4481 error() trying to dereference it. */
4483 (restore_selected_frame
, &inf_status
->selected_frame_id
,
4484 "Unable to restore previously selected frame:\n",
4485 RETURN_MASK_ERROR
) == 0)
4486 /* Error in restoring the selected frame. Select the innermost
4488 select_frame (get_current_frame ());
4496 do_restore_inferior_status_cleanup (void *sts
)
4498 restore_inferior_status (sts
);
4502 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
4504 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
4508 discard_inferior_status (struct inferior_status
*inf_status
)
4510 /* See save_inferior_status for info on stop_bpstat. */
4511 bpstat_clear (&inf_status
->stop_bpstat
);
4512 regcache_xfree (inf_status
->registers
);
4517 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
4519 struct target_waitstatus last
;
4522 get_last_target_status (&last_ptid
, &last
);
4524 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
4527 if (!ptid_equal (last_ptid
, pid
))
4530 *child_pid
= last
.value
.related_pid
;
4535 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
4537 struct target_waitstatus last
;
4540 get_last_target_status (&last_ptid
, &last
);
4542 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
4545 if (!ptid_equal (last_ptid
, pid
))
4548 *child_pid
= last
.value
.related_pid
;
4553 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
4555 struct target_waitstatus last
;
4558 get_last_target_status (&last_ptid
, &last
);
4560 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
4563 if (!ptid_equal (last_ptid
, pid
))
4566 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
4570 /* Oft used ptids */
4572 ptid_t minus_one_ptid
;
4574 /* Create a ptid given the necessary PID, LWP, and TID components. */
4577 ptid_build (int pid
, long lwp
, long tid
)
4587 /* Create a ptid from just a pid. */
4590 pid_to_ptid (int pid
)
4592 return ptid_build (pid
, 0, 0);
4595 /* Fetch the pid (process id) component from a ptid. */
4598 ptid_get_pid (ptid_t ptid
)
4603 /* Fetch the lwp (lightweight process) component from a ptid. */
4606 ptid_get_lwp (ptid_t ptid
)
4611 /* Fetch the tid (thread id) component from a ptid. */
4614 ptid_get_tid (ptid_t ptid
)
4619 /* ptid_equal() is used to test equality of two ptids. */
4622 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
4624 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
4625 && ptid1
.tid
== ptid2
.tid
);
4628 /* restore_inferior_ptid() will be used by the cleanup machinery
4629 to restore the inferior_ptid value saved in a call to
4630 save_inferior_ptid(). */
4633 restore_inferior_ptid (void *arg
)
4635 ptid_t
*saved_ptid_ptr
= arg
;
4636 inferior_ptid
= *saved_ptid_ptr
;
4640 /* Save the value of inferior_ptid so that it may be restored by a
4641 later call to do_cleanups(). Returns the struct cleanup pointer
4642 needed for later doing the cleanup. */
4645 save_inferior_ptid (void)
4647 ptid_t
*saved_ptid_ptr
;
4649 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
4650 *saved_ptid_ptr
= inferior_ptid
;
4651 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
4656 static int non_stop_1
= 0;
4659 set_non_stop (char *args
, int from_tty
,
4660 struct cmd_list_element
*c
)
4662 if (target_has_execution
)
4664 non_stop_1
= non_stop
;
4665 error (_("Cannot change this setting while the inferior is running."));
4668 non_stop
= non_stop_1
;
4672 show_non_stop (struct ui_file
*file
, int from_tty
,
4673 struct cmd_list_element
*c
, const char *value
)
4675 fprintf_filtered (file
,
4676 _("Controlling the inferior in non-stop mode is %s.\n"),
4682 _initialize_infrun (void)
4686 struct cmd_list_element
*c
;
4688 add_info ("signals", signals_info
, _("\
4689 What debugger does when program gets various signals.\n\
4690 Specify a signal as argument to print info on that signal only."));
4691 add_info_alias ("handle", "signals", 0);
4693 add_com ("handle", class_run
, handle_command
, _("\
4694 Specify how to handle a signal.\n\
4695 Args are signals and actions to apply to those signals.\n\
4696 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4697 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4698 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4699 The special arg \"all\" is recognized to mean all signals except those\n\
4700 used by the debugger, typically SIGTRAP and SIGINT.\n\
4701 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4702 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4703 Stop means reenter debugger if this signal happens (implies print).\n\
4704 Print means print a message if this signal happens.\n\
4705 Pass means let program see this signal; otherwise program doesn't know.\n\
4706 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4707 Pass and Stop may be combined."));
4710 add_com ("lz", class_info
, signals_info
, _("\
4711 What debugger does when program gets various signals.\n\
4712 Specify a signal as argument to print info on that signal only."));
4713 add_com ("z", class_run
, xdb_handle_command
, _("\
4714 Specify how to handle a signal.\n\
4715 Args are signals and actions to apply to those signals.\n\
4716 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4717 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4718 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4719 The special arg \"all\" is recognized to mean all signals except those\n\
4720 used by the debugger, typically SIGTRAP and SIGINT.\n\
4721 Recognized actions include \"s\" (toggles between stop and nostop), \n\
4722 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4723 nopass), \"Q\" (noprint)\n\
4724 Stop means reenter debugger if this signal happens (implies print).\n\
4725 Print means print a message if this signal happens.\n\
4726 Pass means let program see this signal; otherwise program doesn't know.\n\
4727 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4728 Pass and Stop may be combined."));
4732 stop_command
= add_cmd ("stop", class_obscure
,
4733 not_just_help_class_command
, _("\
4734 There is no `stop' command, but you can set a hook on `stop'.\n\
4735 This allows you to set a list of commands to be run each time execution\n\
4736 of the program stops."), &cmdlist
);
4738 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
4739 Set inferior debugging."), _("\
4740 Show inferior debugging."), _("\
4741 When non-zero, inferior specific debugging is enabled."),
4744 &setdebuglist
, &showdebuglist
);
4746 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
4747 Set displaced stepping debugging."), _("\
4748 Show displaced stepping debugging."), _("\
4749 When non-zero, displaced stepping specific debugging is enabled."),
4751 show_debug_displaced
,
4752 &setdebuglist
, &showdebuglist
);
4754 add_setshow_boolean_cmd ("non-stop", no_class
,
4756 Set whether gdb controls the inferior in non-stop mode."), _("\
4757 Show whether gdb controls the inferior in non-stop mode."), _("\
4758 When debugging a multi-threaded program and this setting is\n\
4759 off (the default, also called all-stop mode), when one thread stops\n\
4760 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
4761 all other threads in the program while you interact with the thread of\n\
4762 interest. When you continue or step a thread, you can allow the other\n\
4763 threads to run, or have them remain stopped, but while you inspect any\n\
4764 thread's state, all threads stop.\n\
4766 In non-stop mode, when one thread stops, other threads can continue\n\
4767 to run freely. You'll be able to step each thread independently,\n\
4768 leave it stopped or free to run as needed."),
4774 numsigs
= (int) TARGET_SIGNAL_LAST
;
4775 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
4776 signal_print
= (unsigned char *)
4777 xmalloc (sizeof (signal_print
[0]) * numsigs
);
4778 signal_program
= (unsigned char *)
4779 xmalloc (sizeof (signal_program
[0]) * numsigs
);
4780 for (i
= 0; i
< numsigs
; i
++)
4783 signal_print
[i
] = 1;
4784 signal_program
[i
] = 1;
4787 /* Signals caused by debugger's own actions
4788 should not be given to the program afterwards. */
4789 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
4790 signal_program
[TARGET_SIGNAL_INT
] = 0;
4792 /* Signals that are not errors should not normally enter the debugger. */
4793 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
4794 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
4795 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
4796 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
4797 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
4798 signal_print
[TARGET_SIGNAL_PROF
] = 0;
4799 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
4800 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
4801 signal_stop
[TARGET_SIGNAL_IO
] = 0;
4802 signal_print
[TARGET_SIGNAL_IO
] = 0;
4803 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
4804 signal_print
[TARGET_SIGNAL_POLL
] = 0;
4805 signal_stop
[TARGET_SIGNAL_URG
] = 0;
4806 signal_print
[TARGET_SIGNAL_URG
] = 0;
4807 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
4808 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
4810 /* These signals are used internally by user-level thread
4811 implementations. (See signal(5) on Solaris.) Like the above
4812 signals, a healthy program receives and handles them as part of
4813 its normal operation. */
4814 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
4815 signal_print
[TARGET_SIGNAL_LWP
] = 0;
4816 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
4817 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
4818 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
4819 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
4821 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
4822 &stop_on_solib_events
, _("\
4823 Set stopping for shared library events."), _("\
4824 Show stopping for shared library events."), _("\
4825 If nonzero, gdb will give control to the user when the dynamic linker\n\
4826 notifies gdb of shared library events. The most common event of interest\n\
4827 to the user would be loading/unloading of a new library."),
4829 show_stop_on_solib_events
,
4830 &setlist
, &showlist
);
4832 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
4833 follow_fork_mode_kind_names
,
4834 &follow_fork_mode_string
, _("\
4835 Set debugger response to a program call of fork or vfork."), _("\
4836 Show debugger response to a program call of fork or vfork."), _("\
4837 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4838 parent - the original process is debugged after a fork\n\
4839 child - the new process is debugged after a fork\n\
4840 The unfollowed process will continue to run.\n\
4841 By default, the debugger will follow the parent process."),
4843 show_follow_fork_mode_string
,
4844 &setlist
, &showlist
);
4846 add_setshow_enum_cmd ("scheduler-locking", class_run
,
4847 scheduler_enums
, &scheduler_mode
, _("\
4848 Set mode for locking scheduler during execution."), _("\
4849 Show mode for locking scheduler during execution."), _("\
4850 off == no locking (threads may preempt at any time)\n\
4851 on == full locking (no thread except the current thread may run)\n\
4852 step == scheduler locked during every single-step operation.\n\
4853 In this mode, no other thread may run during a step command.\n\
4854 Other threads may run while stepping over a function call ('next')."),
4855 set_schedlock_func
, /* traps on target vector */
4856 show_scheduler_mode
,
4857 &setlist
, &showlist
);
4859 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
4860 Set mode of the step operation."), _("\
4861 Show mode of the step operation."), _("\
4862 When set, doing a step over a function without debug line information\n\
4863 will stop at the first instruction of that function. Otherwise, the\n\
4864 function is skipped and the step command stops at a different source line."),
4866 show_step_stop_if_no_debug
,
4867 &setlist
, &showlist
);
4869 add_setshow_boolean_cmd ("can-use-displaced-stepping", class_maintenance
,
4870 &can_use_displaced_stepping
, _("\
4871 Set debugger's willingness to use displaced stepping."), _("\
4872 Show debugger's willingness to use displaced stepping."), _("\
4873 If zero, gdb will not use displaced stepping to step over\n\
4874 breakpoints, even if such is supported by the target."),
4876 show_can_use_displaced_stepping
,
4877 &maintenance_set_cmdlist
,
4878 &maintenance_show_cmdlist
);
4880 /* ptid initializations */
4881 null_ptid
= ptid_build (0, 0, 0);
4882 minus_one_ptid
= ptid_build (-1, 0, 0);
4883 inferior_ptid
= null_ptid
;
4884 target_last_wait_ptid
= minus_one_ptid
;
4885 displaced_step_ptid
= null_ptid
;
4887 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);