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 /* Reset to normal state. */
1340 init_infwait_state ();
1342 /* Resume inferior. */
1343 resume (oneproc
|| step
|| bpstat_should_step (), stop_signal
);
1345 /* Wait for it to stop (if not standalone)
1346 and in any case decode why it stopped, and act accordingly. */
1347 /* Do this only if we are not using the event loop, or if the target
1348 does not support asynchronous execution. */
1349 if (!target_can_async_p ())
1351 wait_for_inferior (0);
1357 /* Start remote-debugging of a machine over a serial link. */
1360 start_remote (int from_tty
)
1362 init_wait_for_inferior ();
1363 stop_soon
= STOP_QUIETLY_REMOTE
;
1364 stepping_over_breakpoint
= 0;
1366 /* Always go on waiting for the target, regardless of the mode. */
1367 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1368 indicate to wait_for_inferior that a target should timeout if
1369 nothing is returned (instead of just blocking). Because of this,
1370 targets expecting an immediate response need to, internally, set
1371 things up so that the target_wait() is forced to eventually
1373 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1374 differentiate to its caller what the state of the target is after
1375 the initial open has been performed. Here we're assuming that
1376 the target has stopped. It should be possible to eventually have
1377 target_open() return to the caller an indication that the target
1378 is currently running and GDB state should be set to the same as
1379 for an async run. */
1380 wait_for_inferior (0);
1382 /* Now that the inferior has stopped, do any bookkeeping like
1383 loading shared libraries. We want to do this before normal_stop,
1384 so that the displayed frame is up to date. */
1385 post_create_inferior (¤t_target
, from_tty
);
1390 /* Initialize static vars when a new inferior begins. */
1393 init_wait_for_inferior (void)
1395 /* These are meaningless until the first time through wait_for_inferior. */
1398 breakpoint_init_inferior (inf_starting
);
1400 /* Don't confuse first call to proceed(). */
1401 stop_signal
= TARGET_SIGNAL_0
;
1403 /* The first resume is not following a fork/vfork/exec. */
1404 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
; /* I.e., none. */
1406 clear_proceed_status ();
1408 stepping_past_singlestep_breakpoint
= 0;
1409 deferred_step_ptid
= null_ptid
;
1411 target_last_wait_ptid
= minus_one_ptid
;
1413 init_thread_stepping_state (tss
);
1414 previous_inferior_ptid
= null_ptid
;
1415 init_infwait_state ();
1417 displaced_step_clear ();
1421 /* This enum encodes possible reasons for doing a target_wait, so that
1422 wfi can call target_wait in one place. (Ultimately the call will be
1423 moved out of the infinite loop entirely.) */
1427 infwait_normal_state
,
1428 infwait_thread_hop_state
,
1429 infwait_step_watch_state
,
1430 infwait_nonstep_watch_state
1433 /* Why did the inferior stop? Used to print the appropriate messages
1434 to the interface from within handle_inferior_event(). */
1435 enum inferior_stop_reason
1437 /* Step, next, nexti, stepi finished. */
1439 /* Inferior terminated by signal. */
1441 /* Inferior exited. */
1443 /* Inferior received signal, and user asked to be notified. */
1447 /* The PTID we'll do a target_wait on.*/
1450 /* Current inferior wait state. */
1451 enum infwait_states infwait_state
;
1453 /* Data to be passed around while handling an event. This data is
1454 discarded between events. */
1455 struct execution_control_state
1458 struct target_waitstatus ws
;
1460 CORE_ADDR stop_func_start
;
1461 CORE_ADDR stop_func_end
;
1462 char *stop_func_name
;
1463 int new_thread_event
;
1467 void init_execution_control_state (struct execution_control_state
*ecs
);
1469 void handle_inferior_event (struct execution_control_state
*ecs
);
1471 static void step_into_function (struct execution_control_state
*ecs
);
1472 static void insert_step_resume_breakpoint_at_frame (struct frame_info
*step_frame
);
1473 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
1474 static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
1475 struct frame_id sr_id
);
1476 static void insert_longjmp_resume_breakpoint (CORE_ADDR
);
1478 static void stop_stepping (struct execution_control_state
*ecs
);
1479 static void prepare_to_wait (struct execution_control_state
*ecs
);
1480 static void keep_going (struct execution_control_state
*ecs
);
1481 static void print_stop_reason (enum inferior_stop_reason stop_reason
,
1484 /* Wait for control to return from inferior to debugger.
1486 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
1487 as if they were SIGTRAP signals. This can be useful during
1488 the startup sequence on some targets such as HP/UX, where
1489 we receive an EXEC event instead of the expected SIGTRAP.
1491 If inferior gets a signal, we may decide to start it up again
1492 instead of returning. That is why there is a loop in this function.
1493 When this function actually returns it means the inferior
1494 should be left stopped and GDB should read more commands. */
1497 wait_for_inferior (int treat_exec_as_sigtrap
)
1499 struct cleanup
*old_cleanups
;
1500 struct execution_control_state ecss
;
1501 struct execution_control_state
*ecs
;
1505 (gdb_stdlog
, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
1506 treat_exec_as_sigtrap
);
1508 old_cleanups
= make_cleanup (delete_step_resume_breakpoint
,
1509 &step_resume_breakpoint
);
1512 memset (ecs
, 0, sizeof (*ecs
));
1514 overlay_cache_invalid
= 1;
1516 /* We'll update this if & when we switch to a new thread. */
1517 previous_inferior_ptid
= inferior_ptid
;
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;
1571 /* We can only rely on wait_for_more being correct before handling
1572 the event in all-stop, but previous_inferior_ptid isn't used in
1574 if (!ecs
->wait_some_more
)
1575 /* We'll update this if & when we switch to a new thread. */
1576 previous_inferior_ptid
= inferior_ptid
;
1579 /* In non-stop mode, the user/frontend should not notice a thread
1580 switch due to internal events. Make sure we reverse to the
1581 user selected thread and frame after handling the event and
1582 running any breakpoint commands. */
1583 make_cleanup_restore_current_thread ();
1585 /* We have to invalidate the registers BEFORE calling target_wait
1586 because they can be loaded from the target while in target_wait.
1587 This makes remote debugging a bit more efficient for those
1588 targets that provide critical registers as part of their normal
1589 status mechanism. */
1591 registers_changed ();
1593 if (deprecated_target_wait_hook
)
1595 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
);
1597 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
);
1600 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
1601 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1602 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
1603 /* In non-stop mode, each thread is handled individually. Switch
1604 early, so the global state is set correctly for this
1606 context_switch (ecs
->ptid
);
1608 /* Now figure out what to do with the result of the result. */
1609 handle_inferior_event (ecs
);
1611 if (!ecs
->wait_some_more
)
1613 delete_step_resume_breakpoint (&step_resume_breakpoint
);
1615 if (stop_soon
== NO_STOP_QUIETLY
)
1618 if (step_multi
&& stop_step
)
1619 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
1621 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
1624 /* Revert thread and frame. */
1625 do_cleanups (old_chain
);
1627 /* If the inferior was in sync execution mode, and now isn't,
1628 restore the prompt. */
1629 if (was_sync
&& !sync_execution
)
1630 display_gdb_prompt (0);
1633 /* Prepare an execution control state for looping through a
1634 wait_for_inferior-type loop. */
1637 init_execution_control_state (struct execution_control_state
*ecs
)
1639 ecs
->random_signal
= 0;
1642 /* Clear context switchable stepping state. */
1645 init_thread_stepping_state (struct thread_stepping_state
*tss
)
1647 struct symtab_and_line sal
;
1649 tss
->stepping_over_breakpoint
= 0;
1650 tss
->step_after_step_resume_breakpoint
= 0;
1651 tss
->stepping_through_solib_after_catch
= 0;
1652 tss
->stepping_through_solib_catchpoints
= NULL
;
1654 sal
= find_pc_line (prev_pc
, 0);
1655 tss
->current_line
= sal
.line
;
1656 tss
->current_symtab
= sal
.symtab
;
1659 /* Return the cached copy of the last pid/waitstatus returned by
1660 target_wait()/deprecated_target_wait_hook(). The data is actually
1661 cached by handle_inferior_event(), which gets called immediately
1662 after target_wait()/deprecated_target_wait_hook(). */
1665 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
1667 *ptidp
= target_last_wait_ptid
;
1668 *status
= target_last_waitstatus
;
1672 nullify_last_target_wait_ptid (void)
1674 target_last_wait_ptid
= minus_one_ptid
;
1677 /* Switch thread contexts, maintaining "infrun state". */
1680 context_switch (ptid_t ptid
)
1682 /* Caution: it may happen that the new thread (or the old one!)
1683 is not in the thread list. In this case we must not attempt
1684 to "switch context", or we run the risk that our context may
1685 be lost. This may happen as a result of the target module
1686 mishandling thread creation. */
1690 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
1691 target_pid_to_str (inferior_ptid
));
1692 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
1693 target_pid_to_str (ptid
));
1696 if (in_thread_list (inferior_ptid
) && in_thread_list (ptid
))
1697 { /* Perform infrun state context switch: */
1698 /* Save infrun state for the old thread. */
1699 save_infrun_state (inferior_ptid
, prev_pc
,
1700 stepping_over_breakpoint
, step_resume_breakpoint
,
1702 step_range_end
, &step_frame_id
,
1703 tss
->stepping_over_breakpoint
,
1704 tss
->stepping_through_solib_after_catch
,
1705 tss
->stepping_through_solib_catchpoints
,
1706 tss
->current_line
, tss
->current_symtab
,
1707 cmd_continuation
, intermediate_continuation
,
1715 /* Load infrun state for the new thread. */
1716 load_infrun_state (ptid
, &prev_pc
,
1717 &stepping_over_breakpoint
, &step_resume_breakpoint
,
1719 &step_range_end
, &step_frame_id
,
1720 &tss
->stepping_over_breakpoint
,
1721 &tss
->stepping_through_solib_after_catch
,
1722 &tss
->stepping_through_solib_catchpoints
,
1723 &tss
->current_line
, &tss
->current_symtab
,
1724 &cmd_continuation
, &intermediate_continuation
,
1733 switch_to_thread (ptid
);
1736 /* Context switch to thread PTID. */
1738 context_switch_to (ptid_t ptid
)
1740 ptid_t current_ptid
= inferior_ptid
;
1742 /* Context switch to the new thread. */
1743 if (!ptid_equal (ptid
, inferior_ptid
))
1745 context_switch (ptid
);
1747 return current_ptid
;
1751 adjust_pc_after_break (struct execution_control_state
*ecs
)
1753 struct regcache
*regcache
;
1754 struct gdbarch
*gdbarch
;
1755 CORE_ADDR breakpoint_pc
;
1757 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
1758 we aren't, just return.
1760 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
1761 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
1762 implemented by software breakpoints should be handled through the normal
1765 NOTE drow/2004-01-31: On some targets, breakpoints may generate
1766 different signals (SIGILL or SIGEMT for instance), but it is less
1767 clear where the PC is pointing afterwards. It may not match
1768 gdbarch_decr_pc_after_break. I don't know any specific target that
1769 generates these signals at breakpoints (the code has been in GDB since at
1770 least 1992) so I can not guess how to handle them here.
1772 In earlier versions of GDB, a target with
1773 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
1774 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
1775 target with both of these set in GDB history, and it seems unlikely to be
1776 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
1778 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
1781 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1784 /* If this target does not decrement the PC after breakpoints, then
1785 we have nothing to do. */
1786 regcache
= get_thread_regcache (ecs
->ptid
);
1787 gdbarch
= get_regcache_arch (regcache
);
1788 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
1791 /* Find the location where (if we've hit a breakpoint) the
1792 breakpoint would be. */
1793 breakpoint_pc
= regcache_read_pc (regcache
)
1794 - gdbarch_decr_pc_after_break (gdbarch
);
1796 /* Check whether there actually is a software breakpoint inserted
1797 at that location. */
1798 if (software_breakpoint_inserted_here_p (breakpoint_pc
))
1800 /* When using hardware single-step, a SIGTRAP is reported for both
1801 a completed single-step and a software breakpoint. Need to
1802 differentiate between the two, as the latter needs adjusting
1803 but the former does not.
1805 The SIGTRAP can be due to a completed hardware single-step only if
1806 - we didn't insert software single-step breakpoints
1807 - the thread to be examined is still the current thread
1808 - this thread is currently being stepped
1810 If any of these events did not occur, we must have stopped due
1811 to hitting a software breakpoint, and have to back up to the
1814 As a special case, we could have hardware single-stepped a
1815 software breakpoint. In this case (prev_pc == breakpoint_pc),
1816 we also need to back up to the breakpoint address. */
1818 if (singlestep_breakpoints_inserted_p
1819 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
1820 || !currently_stepping (tss
)
1821 || prev_pc
== breakpoint_pc
)
1822 regcache_write_pc (regcache
, breakpoint_pc
);
1827 init_infwait_state (void)
1829 waiton_ptid
= pid_to_ptid (-1);
1830 infwait_state
= infwait_normal_state
;
1834 error_is_running (void)
1837 Cannot execute this command while the selected thread is running."));
1841 ensure_not_running (void)
1843 if (is_running (inferior_ptid
))
1844 error_is_running ();
1847 /* Given an execution control state that has been freshly filled in
1848 by an event from the inferior, figure out what it means and take
1849 appropriate action. */
1852 handle_inferior_event (struct execution_control_state
*ecs
)
1854 int sw_single_step_trap_p
= 0;
1855 int stopped_by_watchpoint
;
1856 int stepped_after_stopped_by_watchpoint
= 0;
1857 struct symtab_and_line stop_pc_sal
;
1859 breakpoint_retire_moribund ();
1861 /* Cache the last pid/waitstatus. */
1862 target_last_wait_ptid
= ecs
->ptid
;
1863 target_last_waitstatus
= ecs
->ws
;
1865 /* Always clear state belonging to the previous time we stopped. */
1866 stop_stack_dummy
= 0;
1868 adjust_pc_after_break (ecs
);
1870 reinit_frame_cache ();
1872 /* If it's a new process, add it to the thread database */
1874 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
1875 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
1876 && !in_thread_list (ecs
->ptid
));
1878 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1879 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
1880 add_thread (ecs
->ptid
);
1882 if (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
1884 /* Mark the non-executing threads accordingly. */
1886 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
1887 || ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
1888 set_executing (pid_to_ptid (-1), 0);
1890 set_executing (ecs
->ptid
, 0);
1893 switch (infwait_state
)
1895 case infwait_thread_hop_state
:
1897 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
1898 /* Cancel the waiton_ptid. */
1899 waiton_ptid
= pid_to_ptid (-1);
1902 case infwait_normal_state
:
1904 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
1907 case infwait_step_watch_state
:
1909 fprintf_unfiltered (gdb_stdlog
,
1910 "infrun: infwait_step_watch_state\n");
1912 stepped_after_stopped_by_watchpoint
= 1;
1915 case infwait_nonstep_watch_state
:
1917 fprintf_unfiltered (gdb_stdlog
,
1918 "infrun: infwait_nonstep_watch_state\n");
1919 insert_breakpoints ();
1921 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1922 handle things like signals arriving and other things happening
1923 in combination correctly? */
1924 stepped_after_stopped_by_watchpoint
= 1;
1928 internal_error (__FILE__
, __LINE__
, _("bad switch"));
1930 infwait_state
= infwait_normal_state
;
1932 switch (ecs
->ws
.kind
)
1934 case TARGET_WAITKIND_LOADED
:
1936 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
1937 /* Ignore gracefully during startup of the inferior, as it might
1938 be the shell which has just loaded some objects, otherwise
1939 add the symbols for the newly loaded objects. Also ignore at
1940 the beginning of an attach or remote session; we will query
1941 the full list of libraries once the connection is
1943 if (stop_soon
== NO_STOP_QUIETLY
)
1945 /* Check for any newly added shared libraries if we're
1946 supposed to be adding them automatically. Switch
1947 terminal for any messages produced by
1948 breakpoint_re_set. */
1949 target_terminal_ours_for_output ();
1950 /* NOTE: cagney/2003-11-25: Make certain that the target
1951 stack's section table is kept up-to-date. Architectures,
1952 (e.g., PPC64), use the section table to perform
1953 operations such as address => section name and hence
1954 require the table to contain all sections (including
1955 those found in shared libraries). */
1956 /* NOTE: cagney/2003-11-25: Pass current_target and not
1957 exec_ops to SOLIB_ADD. This is because current GDB is
1958 only tooled to propagate section_table changes out from
1959 the "current_target" (see target_resize_to_sections), and
1960 not up from the exec stratum. This, of course, isn't
1961 right. "infrun.c" should only interact with the
1962 exec/process stratum, instead relying on the target stack
1963 to propagate relevant changes (stop, section table
1964 changed, ...) up to other layers. */
1966 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
1968 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
1970 target_terminal_inferior ();
1972 /* If requested, stop when the dynamic linker notifies
1973 gdb of events. This allows the user to get control
1974 and place breakpoints in initializer routines for
1975 dynamically loaded objects (among other things). */
1976 if (stop_on_solib_events
)
1978 stop_stepping (ecs
);
1982 /* NOTE drow/2007-05-11: This might be a good place to check
1983 for "catch load". */
1986 /* If we are skipping through a shell, or through shared library
1987 loading that we aren't interested in, resume the program. If
1988 we're running the program normally, also resume. But stop if
1989 we're attaching or setting up a remote connection. */
1990 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
1992 /* Loading of shared libraries might have changed breakpoint
1993 addresses. Make sure new breakpoints are inserted. */
1994 if (stop_soon
== NO_STOP_QUIETLY
1995 && !breakpoints_always_inserted_mode ())
1996 insert_breakpoints ();
1997 resume (0, TARGET_SIGNAL_0
);
1998 prepare_to_wait (ecs
);
2004 case TARGET_WAITKIND_SPURIOUS
:
2006 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
2007 resume (0, TARGET_SIGNAL_0
);
2008 prepare_to_wait (ecs
);
2011 case TARGET_WAITKIND_EXITED
:
2013 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
2014 target_terminal_ours (); /* Must do this before mourn anyway */
2015 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
2017 /* Record the exit code in the convenience variable $_exitcode, so
2018 that the user can inspect this again later. */
2019 set_internalvar (lookup_internalvar ("_exitcode"),
2020 value_from_longest (builtin_type_int
,
2021 (LONGEST
) ecs
->ws
.value
.integer
));
2022 gdb_flush (gdb_stdout
);
2023 target_mourn_inferior ();
2024 singlestep_breakpoints_inserted_p
= 0;
2025 stop_print_frame
= 0;
2026 stop_stepping (ecs
);
2029 case TARGET_WAITKIND_SIGNALLED
:
2031 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2032 stop_print_frame
= 0;
2033 stop_signal
= ecs
->ws
.value
.sig
;
2034 target_terminal_ours (); /* Must do this before mourn anyway */
2036 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2037 reach here unless the inferior is dead. However, for years
2038 target_kill() was called here, which hints that fatal signals aren't
2039 really fatal on some systems. If that's true, then some changes
2041 target_mourn_inferior ();
2043 print_stop_reason (SIGNAL_EXITED
, stop_signal
);
2044 singlestep_breakpoints_inserted_p
= 0;
2045 stop_stepping (ecs
);
2048 /* The following are the only cases in which we keep going;
2049 the above cases end in a continue or goto. */
2050 case TARGET_WAITKIND_FORKED
:
2051 case TARGET_WAITKIND_VFORKED
:
2053 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2054 stop_signal
= TARGET_SIGNAL_TRAP
;
2055 pending_follow
.kind
= ecs
->ws
.kind
;
2057 pending_follow
.fork_event
.parent_pid
= ecs
->ptid
;
2058 pending_follow
.fork_event
.child_pid
= ecs
->ws
.value
.related_pid
;
2060 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2062 context_switch (ecs
->ptid
);
2063 reinit_frame_cache ();
2066 stop_pc
= read_pc ();
2068 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2070 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2072 /* If no catchpoint triggered for this, then keep going. */
2073 if (ecs
->random_signal
)
2075 stop_signal
= TARGET_SIGNAL_0
;
2079 goto process_event_stop_test
;
2081 case TARGET_WAITKIND_EXECD
:
2083 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
2084 stop_signal
= TARGET_SIGNAL_TRAP
;
2086 pending_follow
.execd_pathname
=
2087 savestring (ecs
->ws
.value
.execd_pathname
,
2088 strlen (ecs
->ws
.value
.execd_pathname
));
2090 /* This causes the eventpoints and symbol table to be reset. Must
2091 do this now, before trying to determine whether to stop. */
2092 follow_exec (inferior_ptid
, pending_follow
.execd_pathname
);
2093 xfree (pending_follow
.execd_pathname
);
2095 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2098 /* The breakpoints module may need to touch the inferior's
2099 memory. Switch to the (stopped) event ptid
2101 ptid_t saved_inferior_ptid
= inferior_ptid
;
2102 inferior_ptid
= ecs
->ptid
;
2104 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2106 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2107 inferior_ptid
= saved_inferior_ptid
;
2110 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2112 context_switch (ecs
->ptid
);
2113 reinit_frame_cache ();
2116 /* If no catchpoint triggered for this, then keep going. */
2117 if (ecs
->random_signal
)
2119 stop_signal
= TARGET_SIGNAL_0
;
2123 goto process_event_stop_test
;
2125 /* Be careful not to try to gather much state about a thread
2126 that's in a syscall. It's frequently a losing proposition. */
2127 case TARGET_WAITKIND_SYSCALL_ENTRY
:
2129 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2130 resume (0, TARGET_SIGNAL_0
);
2131 prepare_to_wait (ecs
);
2134 /* Before examining the threads further, step this thread to
2135 get it entirely out of the syscall. (We get notice of the
2136 event when the thread is just on the verge of exiting a
2137 syscall. Stepping one instruction seems to get it back
2139 case TARGET_WAITKIND_SYSCALL_RETURN
:
2141 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2142 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
);
2143 prepare_to_wait (ecs
);
2146 case TARGET_WAITKIND_STOPPED
:
2148 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
2149 stop_signal
= ecs
->ws
.value
.sig
;
2152 /* We had an event in the inferior, but we are not interested
2153 in handling it at this level. The lower layers have already
2154 done what needs to be done, if anything.
2156 One of the possible circumstances for this is when the
2157 inferior produces output for the console. The inferior has
2158 not stopped, and we are ignoring the event. Another possible
2159 circumstance is any event which the lower level knows will be
2160 reported multiple times without an intervening resume. */
2161 case TARGET_WAITKIND_IGNORE
:
2163 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2164 prepare_to_wait (ecs
);
2168 if (ecs
->new_thread_event
)
2171 /* Non-stop assumes that the target handles adding new threads
2172 to the thread list. */
2173 internal_error (__FILE__
, __LINE__
, "\
2174 targets should add new threads to the thread list themselves in non-stop mode.");
2176 /* We may want to consider not doing a resume here in order to
2177 give the user a chance to play with the new thread. It might
2178 be good to make that a user-settable option. */
2180 /* At this point, all threads are stopped (happens automatically
2181 in either the OS or the native code). Therefore we need to
2182 continue all threads in order to make progress. */
2184 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
2185 prepare_to_wait (ecs
);
2189 /* Do we need to clean up the state of a thread that has completed a
2190 displaced single-step? (Doing so usually affects the PC, so do
2191 it here, before we set stop_pc.) */
2192 displaced_step_fixup (ecs
->ptid
, stop_signal
);
2194 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2198 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = 0x%s\n",
2199 paddr_nz (stop_pc
));
2200 if (STOPPED_BY_WATCHPOINT (&ecs
->ws
))
2203 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
2205 if (target_stopped_data_address (¤t_target
, &addr
))
2206 fprintf_unfiltered (gdb_stdlog
,
2207 "infrun: stopped data address = 0x%s\n",
2210 fprintf_unfiltered (gdb_stdlog
,
2211 "infrun: (no data address available)\n");
2215 if (stepping_past_singlestep_breakpoint
)
2217 gdb_assert (singlestep_breakpoints_inserted_p
);
2218 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
2219 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
2221 stepping_past_singlestep_breakpoint
= 0;
2223 /* We've either finished single-stepping past the single-step
2224 breakpoint, or stopped for some other reason. It would be nice if
2225 we could tell, but we can't reliably. */
2226 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2229 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
2230 /* Pull the single step breakpoints out of the target. */
2231 remove_single_step_breakpoints ();
2232 singlestep_breakpoints_inserted_p
= 0;
2234 ecs
->random_signal
= 0;
2236 context_switch (saved_singlestep_ptid
);
2237 if (deprecated_context_hook
)
2238 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2240 resume (1, TARGET_SIGNAL_0
);
2241 prepare_to_wait (ecs
);
2246 stepping_past_singlestep_breakpoint
= 0;
2248 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
2250 /* In non-stop mode, there's never a deferred_step_ptid set. */
2251 gdb_assert (!non_stop
);
2253 /* If we stopped for some other reason than single-stepping, ignore
2254 the fact that we were supposed to switch back. */
2255 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2258 fprintf_unfiltered (gdb_stdlog
,
2259 "infrun: handling deferred step\n");
2261 /* Pull the single step breakpoints out of the target. */
2262 if (singlestep_breakpoints_inserted_p
)
2264 remove_single_step_breakpoints ();
2265 singlestep_breakpoints_inserted_p
= 0;
2268 /* Note: We do not call context_switch at this point, as the
2269 context is already set up for stepping the original thread. */
2270 switch_to_thread (deferred_step_ptid
);
2271 deferred_step_ptid
= null_ptid
;
2272 /* Suppress spurious "Switching to ..." message. */
2273 previous_inferior_ptid
= inferior_ptid
;
2275 resume (1, TARGET_SIGNAL_0
);
2276 prepare_to_wait (ecs
);
2280 deferred_step_ptid
= null_ptid
;
2283 /* See if a thread hit a thread-specific breakpoint that was meant for
2284 another thread. If so, then step that thread past the breakpoint,
2287 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2289 int thread_hop_needed
= 0;
2291 /* Check if a regular breakpoint has been hit before checking
2292 for a potential single step breakpoint. Otherwise, GDB will
2293 not see this breakpoint hit when stepping onto breakpoints. */
2294 if (regular_breakpoint_inserted_here_p (stop_pc
))
2296 ecs
->random_signal
= 0;
2297 if (!breakpoint_thread_match (stop_pc
, ecs
->ptid
))
2298 thread_hop_needed
= 1;
2300 else if (singlestep_breakpoints_inserted_p
)
2302 /* We have not context switched yet, so this should be true
2303 no matter which thread hit the singlestep breakpoint. */
2304 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
2306 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
2308 target_pid_to_str (ecs
->ptid
));
2310 ecs
->random_signal
= 0;
2311 /* The call to in_thread_list is necessary because PTIDs sometimes
2312 change when we go from single-threaded to multi-threaded. If
2313 the singlestep_ptid is still in the list, assume that it is
2314 really different from ecs->ptid. */
2315 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
2316 && in_thread_list (singlestep_ptid
))
2318 /* If the PC of the thread we were trying to single-step
2319 has changed, discard this event (which we were going
2320 to ignore anyway), and pretend we saw that thread
2321 trap. This prevents us continuously moving the
2322 single-step breakpoint forward, one instruction at a
2323 time. If the PC has changed, then the thread we were
2324 trying to single-step has trapped or been signalled,
2325 but the event has not been reported to GDB yet.
2327 There might be some cases where this loses signal
2328 information, if a signal has arrived at exactly the
2329 same time that the PC changed, but this is the best
2330 we can do with the information available. Perhaps we
2331 should arrange to report all events for all threads
2332 when they stop, or to re-poll the remote looking for
2333 this particular thread (i.e. temporarily enable
2336 CORE_ADDR new_singlestep_pc
2337 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
2339 if (new_singlestep_pc
!= singlestep_pc
)
2342 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
2343 " but expected thread advanced also\n");
2345 /* The current context still belongs to
2346 singlestep_ptid. Don't swap here, since that's
2347 the context we want to use. Just fudge our
2348 state and continue. */
2349 ecs
->ptid
= singlestep_ptid
;
2350 stop_pc
= new_singlestep_pc
;
2355 fprintf_unfiltered (gdb_stdlog
,
2356 "infrun: unexpected thread\n");
2358 thread_hop_needed
= 1;
2359 stepping_past_singlestep_breakpoint
= 1;
2360 saved_singlestep_ptid
= singlestep_ptid
;
2365 if (thread_hop_needed
)
2367 int remove_status
= 0;
2370 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
2372 /* Saw a breakpoint, but it was hit by the wrong thread.
2375 if (singlestep_breakpoints_inserted_p
)
2377 /* Pull the single step breakpoints out of the target. */
2378 remove_single_step_breakpoints ();
2379 singlestep_breakpoints_inserted_p
= 0;
2382 /* If the arch can displace step, don't remove the
2384 if (!use_displaced_stepping (current_gdbarch
))
2385 remove_status
= remove_breakpoints ();
2387 /* Did we fail to remove breakpoints? If so, try
2388 to set the PC past the bp. (There's at least
2389 one situation in which we can fail to remove
2390 the bp's: On HP-UX's that use ttrace, we can't
2391 change the address space of a vforking child
2392 process until the child exits (well, okay, not
2393 then either :-) or execs. */
2394 if (remove_status
!= 0)
2395 error (_("Cannot step over breakpoint hit in wrong thread"));
2398 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
2399 context_switch (ecs
->ptid
);
2403 /* Only need to require the next event from this
2404 thread in all-stop mode. */
2405 waiton_ptid
= ecs
->ptid
;
2406 infwait_state
= infwait_thread_hop_state
;
2409 tss
->stepping_over_breakpoint
= 1;
2411 registers_changed ();
2415 else if (singlestep_breakpoints_inserted_p
)
2417 sw_single_step_trap_p
= 1;
2418 ecs
->random_signal
= 0;
2422 ecs
->random_signal
= 1;
2424 /* See if something interesting happened to the non-current thread. If
2425 so, then switch to that thread. */
2426 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2429 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
2431 context_switch (ecs
->ptid
);
2433 if (deprecated_context_hook
)
2434 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2437 if (singlestep_breakpoints_inserted_p
)
2439 /* Pull the single step breakpoints out of the target. */
2440 remove_single_step_breakpoints ();
2441 singlestep_breakpoints_inserted_p
= 0;
2444 if (stepped_after_stopped_by_watchpoint
)
2445 stopped_by_watchpoint
= 0;
2447 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
2449 /* If necessary, step over this watchpoint. We'll be back to display
2451 if (stopped_by_watchpoint
2452 && (HAVE_STEPPABLE_WATCHPOINT
2453 || gdbarch_have_nonsteppable_watchpoint (current_gdbarch
)))
2455 /* At this point, we are stopped at an instruction which has
2456 attempted to write to a piece of memory under control of
2457 a watchpoint. The instruction hasn't actually executed
2458 yet. If we were to evaluate the watchpoint expression
2459 now, we would get the old value, and therefore no change
2460 would seem to have occurred.
2462 In order to make watchpoints work `right', we really need
2463 to complete the memory write, and then evaluate the
2464 watchpoint expression. We do this by single-stepping the
2467 It may not be necessary to disable the watchpoint to stop over
2468 it. For example, the PA can (with some kernel cooperation)
2469 single step over a watchpoint without disabling the watchpoint.
2471 It is far more common to need to disable a watchpoint to step
2472 the inferior over it. If we have non-steppable watchpoints,
2473 we must disable the current watchpoint; it's simplest to
2474 disable all watchpoints and breakpoints. */
2476 if (!HAVE_STEPPABLE_WATCHPOINT
)
2477 remove_breakpoints ();
2478 registers_changed ();
2479 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
); /* Single step */
2480 waiton_ptid
= ecs
->ptid
;
2481 if (HAVE_STEPPABLE_WATCHPOINT
)
2482 infwait_state
= infwait_step_watch_state
;
2484 infwait_state
= infwait_nonstep_watch_state
;
2485 prepare_to_wait (ecs
);
2489 ecs
->stop_func_start
= 0;
2490 ecs
->stop_func_end
= 0;
2491 ecs
->stop_func_name
= 0;
2492 /* Don't care about return value; stop_func_start and stop_func_name
2493 will both be 0 if it doesn't work. */
2494 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
2495 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
2496 ecs
->stop_func_start
2497 += gdbarch_deprecated_function_start_offset (current_gdbarch
);
2498 tss
->stepping_over_breakpoint
= 0;
2499 bpstat_clear (&stop_bpstat
);
2501 stop_print_frame
= 1;
2502 ecs
->random_signal
= 0;
2503 stopped_by_random_signal
= 0;
2505 if (stop_signal
== TARGET_SIGNAL_TRAP
2506 && stepping_over_breakpoint
2507 && gdbarch_single_step_through_delay_p (current_gdbarch
)
2508 && currently_stepping (tss
))
2510 /* We're trying to step off a breakpoint. Turns out that we're
2511 also on an instruction that needs to be stepped multiple
2512 times before it's been fully executing. E.g., architectures
2513 with a delay slot. It needs to be stepped twice, once for
2514 the instruction and once for the delay slot. */
2515 int step_through_delay
2516 = gdbarch_single_step_through_delay (current_gdbarch
,
2517 get_current_frame ());
2518 if (debug_infrun
&& step_through_delay
)
2519 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
2520 if (step_range_end
== 0 && step_through_delay
)
2522 /* The user issued a continue when stopped at a breakpoint.
2523 Set up for another trap and get out of here. */
2524 tss
->stepping_over_breakpoint
= 1;
2528 else if (step_through_delay
)
2530 /* The user issued a step when stopped at a breakpoint.
2531 Maybe we should stop, maybe we should not - the delay
2532 slot *might* correspond to a line of source. In any
2533 case, don't decide that here, just set
2534 ecs->stepping_over_breakpoint, making sure we
2535 single-step again before breakpoints are re-inserted. */
2536 tss
->stepping_over_breakpoint
= 1;
2540 /* Look at the cause of the stop, and decide what to do.
2541 The alternatives are:
2542 1) stop_stepping and return; to really stop and return to the debugger,
2543 2) keep_going and return to start up again
2544 (set tss->stepping_over_breakpoint to 1 to single step once)
2545 3) set ecs->random_signal to 1, and the decision between 1 and 2
2546 will be made according to the signal handling tables. */
2548 /* First, distinguish signals caused by the debugger from signals
2549 that have to do with the program's own actions. Note that
2550 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
2551 on the operating system version. Here we detect when a SIGILL or
2552 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
2553 something similar for SIGSEGV, since a SIGSEGV will be generated
2554 when we're trying to execute a breakpoint instruction on a
2555 non-executable stack. This happens for call dummy breakpoints
2556 for architectures like SPARC that place call dummies on the
2559 If we're doing a displaced step past a breakpoint, then the
2560 breakpoint is always inserted at the original instruction;
2561 non-standard signals can't be explained by the breakpoint. */
2562 if (stop_signal
== TARGET_SIGNAL_TRAP
2563 || (! stepping_over_breakpoint
2564 && breakpoint_inserted_here_p (stop_pc
)
2565 && (stop_signal
== TARGET_SIGNAL_ILL
2566 || stop_signal
== TARGET_SIGNAL_SEGV
2567 || stop_signal
== TARGET_SIGNAL_EMT
))
2568 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2569 || stop_soon
== STOP_QUIETLY_REMOTE
)
2571 if (stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
2574 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
2575 stop_print_frame
= 0;
2576 stop_stepping (ecs
);
2580 /* This is originated from start_remote(), start_inferior() and
2581 shared libraries hook functions. */
2582 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
2585 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
2586 stop_stepping (ecs
);
2590 /* This originates from attach_command(). We need to overwrite
2591 the stop_signal here, because some kernels don't ignore a
2592 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
2593 See more comments in inferior.h. On the other hand, if we
2594 get a non-SIGSTOP, report it to the user - assume the backend
2595 will handle the SIGSTOP if it should show up later.
2597 Also consider that the attach is complete when we see a
2598 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
2599 target extended-remote report it instead of a SIGSTOP
2600 (e.g. gdbserver). We already rely on SIGTRAP being our
2601 signal, so this is no exception. */
2602 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2603 && (stop_signal
== TARGET_SIGNAL_STOP
2604 || stop_signal
== TARGET_SIGNAL_TRAP
))
2606 stop_stepping (ecs
);
2607 stop_signal
= TARGET_SIGNAL_0
;
2611 /* See if there is a breakpoint at the current PC. */
2612 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2614 /* Following in case break condition called a
2616 stop_print_frame
= 1;
2618 /* NOTE: cagney/2003-03-29: These two checks for a random signal
2619 at one stage in the past included checks for an inferior
2620 function call's call dummy's return breakpoint. The original
2621 comment, that went with the test, read:
2623 ``End of a stack dummy. Some systems (e.g. Sony news) give
2624 another signal besides SIGTRAP, so check here as well as
2627 If someone ever tries to get get call dummys on a
2628 non-executable stack to work (where the target would stop
2629 with something like a SIGSEGV), then those tests might need
2630 to be re-instated. Given, however, that the tests were only
2631 enabled when momentary breakpoints were not being used, I
2632 suspect that it won't be the case.
2634 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
2635 be necessary for call dummies on a non-executable stack on
2638 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2640 = !(bpstat_explains_signal (stop_bpstat
)
2641 || stepping_over_breakpoint
2642 || (step_range_end
&& step_resume_breakpoint
== NULL
));
2645 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2646 if (!ecs
->random_signal
)
2647 stop_signal
= TARGET_SIGNAL_TRAP
;
2651 /* When we reach this point, we've pretty much decided
2652 that the reason for stopping must've been a random
2653 (unexpected) signal. */
2656 ecs
->random_signal
= 1;
2658 process_event_stop_test
:
2659 /* For the program's own signals, act according to
2660 the signal handling tables. */
2662 if (ecs
->random_signal
)
2664 /* Signal not for debugging purposes. */
2668 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n", stop_signal
);
2670 stopped_by_random_signal
= 1;
2672 if (signal_print
[stop_signal
])
2675 target_terminal_ours_for_output ();
2676 print_stop_reason (SIGNAL_RECEIVED
, stop_signal
);
2678 if (signal_stop_state (stop_signal
))
2680 stop_stepping (ecs
);
2683 /* If not going to stop, give terminal back
2684 if we took it away. */
2686 target_terminal_inferior ();
2688 /* Clear the signal if it should not be passed. */
2689 if (signal_program
[stop_signal
] == 0)
2690 stop_signal
= TARGET_SIGNAL_0
;
2692 if (prev_pc
== read_pc ()
2693 && stepping_over_breakpoint
2694 && step_resume_breakpoint
== NULL
)
2696 /* We were just starting a new sequence, attempting to
2697 single-step off of a breakpoint and expecting a SIGTRAP.
2698 Instead this signal arrives. This signal will take us out
2699 of the stepping range so GDB needs to remember to, when
2700 the signal handler returns, resume stepping off that
2702 /* To simplify things, "continue" is forced to use the same
2703 code paths as single-step - set a breakpoint at the
2704 signal return address and then, once hit, step off that
2707 fprintf_unfiltered (gdb_stdlog
,
2708 "infrun: signal arrived while stepping over "
2711 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2712 tss
->step_after_step_resume_breakpoint
= 1;
2717 if (step_range_end
!= 0
2718 && stop_signal
!= TARGET_SIGNAL_0
2719 && stop_pc
>= step_range_start
&& stop_pc
< step_range_end
2720 && frame_id_eq (get_frame_id (get_current_frame ()),
2722 && step_resume_breakpoint
== NULL
)
2724 /* The inferior is about to take a signal that will take it
2725 out of the single step range. Set a breakpoint at the
2726 current PC (which is presumably where the signal handler
2727 will eventually return) and then allow the inferior to
2730 Note that this is only needed for a signal delivered
2731 while in the single-step range. Nested signals aren't a
2732 problem as they eventually all return. */
2734 fprintf_unfiltered (gdb_stdlog
,
2735 "infrun: signal may take us out of "
2736 "single-step range\n");
2738 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2743 /* Note: step_resume_breakpoint may be non-NULL. This occures
2744 when either there's a nested signal, or when there's a
2745 pending signal enabled just as the signal handler returns
2746 (leaving the inferior at the step-resume-breakpoint without
2747 actually executing it). Either way continue until the
2748 breakpoint is really hit. */
2753 /* Handle cases caused by hitting a breakpoint. */
2755 CORE_ADDR jmp_buf_pc
;
2756 struct bpstat_what what
;
2758 what
= bpstat_what (stop_bpstat
);
2760 if (what
.call_dummy
)
2762 stop_stack_dummy
= 1;
2765 switch (what
.main_action
)
2767 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
2768 /* If we hit the breakpoint at longjmp while stepping, we
2769 install a momentary breakpoint at the target of the
2773 fprintf_unfiltered (gdb_stdlog
,
2774 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
2776 tss
->stepping_over_breakpoint
= 1;
2778 if (!gdbarch_get_longjmp_target_p (current_gdbarch
)
2779 || !gdbarch_get_longjmp_target (current_gdbarch
,
2780 get_current_frame (), &jmp_buf_pc
))
2783 fprintf_unfiltered (gdb_stdlog
, "\
2784 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
2789 /* We're going to replace the current step-resume breakpoint
2790 with a longjmp-resume breakpoint. */
2791 if (step_resume_breakpoint
!= NULL
)
2792 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2794 /* Insert a breakpoint at resume address. */
2795 insert_longjmp_resume_breakpoint (jmp_buf_pc
);
2800 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
2802 fprintf_unfiltered (gdb_stdlog
,
2803 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
2805 gdb_assert (step_resume_breakpoint
!= NULL
);
2806 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2809 print_stop_reason (END_STEPPING_RANGE
, 0);
2810 stop_stepping (ecs
);
2813 case BPSTAT_WHAT_SINGLE
:
2815 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
2816 tss
->stepping_over_breakpoint
= 1;
2817 /* Still need to check other stuff, at least the case
2818 where we are stepping and step out of the right range. */
2821 case BPSTAT_WHAT_STOP_NOISY
:
2823 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
2824 stop_print_frame
= 1;
2826 /* We are about to nuke the step_resume_breakpointt via the
2827 cleanup chain, so no need to worry about it here. */
2829 stop_stepping (ecs
);
2832 case BPSTAT_WHAT_STOP_SILENT
:
2834 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
2835 stop_print_frame
= 0;
2837 /* We are about to nuke the step_resume_breakpoin via the
2838 cleanup chain, so no need to worry about it here. */
2840 stop_stepping (ecs
);
2843 case BPSTAT_WHAT_STEP_RESUME
:
2844 /* This proably demands a more elegant solution, but, yeah
2847 This function's use of the simple variable
2848 step_resume_breakpoint doesn't seem to accomodate
2849 simultaneously active step-resume bp's, although the
2850 breakpoint list certainly can.
2852 If we reach here and step_resume_breakpoint is already
2853 NULL, then apparently we have multiple active
2854 step-resume bp's. We'll just delete the breakpoint we
2855 stopped at, and carry on.
2857 Correction: what the code currently does is delete a
2858 step-resume bp, but it makes no effort to ensure that
2859 the one deleted is the one currently stopped at. MVS */
2862 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
2864 if (step_resume_breakpoint
== NULL
)
2866 step_resume_breakpoint
=
2867 bpstat_find_step_resume_breakpoint (stop_bpstat
);
2869 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2870 if (tss
->step_after_step_resume_breakpoint
)
2872 /* Back when the step-resume breakpoint was inserted, we
2873 were trying to single-step off a breakpoint. Go back
2875 tss
->step_after_step_resume_breakpoint
= 0;
2876 tss
->stepping_over_breakpoint
= 1;
2882 case BPSTAT_WHAT_CHECK_SHLIBS
:
2883 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
:
2886 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
2888 /* Check for any newly added shared libraries if we're
2889 supposed to be adding them automatically. Switch
2890 terminal for any messages produced by
2891 breakpoint_re_set. */
2892 target_terminal_ours_for_output ();
2893 /* NOTE: cagney/2003-11-25: Make certain that the target
2894 stack's section table is kept up-to-date. Architectures,
2895 (e.g., PPC64), use the section table to perform
2896 operations such as address => section name and hence
2897 require the table to contain all sections (including
2898 those found in shared libraries). */
2899 /* NOTE: cagney/2003-11-25: Pass current_target and not
2900 exec_ops to SOLIB_ADD. This is because current GDB is
2901 only tooled to propagate section_table changes out from
2902 the "current_target" (see target_resize_to_sections), and
2903 not up from the exec stratum. This, of course, isn't
2904 right. "infrun.c" should only interact with the
2905 exec/process stratum, instead relying on the target stack
2906 to propagate relevant changes (stop, section table
2907 changed, ...) up to other layers. */
2909 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2911 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2913 target_terminal_inferior ();
2915 /* If requested, stop when the dynamic linker notifies
2916 gdb of events. This allows the user to get control
2917 and place breakpoints in initializer routines for
2918 dynamically loaded objects (among other things). */
2919 if (stop_on_solib_events
|| stop_stack_dummy
)
2921 stop_stepping (ecs
);
2925 /* If we stopped due to an explicit catchpoint, then the
2926 (see above) call to SOLIB_ADD pulled in any symbols
2927 from a newly-loaded library, if appropriate.
2929 We do want the inferior to stop, but not where it is
2930 now, which is in the dynamic linker callback. Rather,
2931 we would like it stop in the user's program, just after
2932 the call that caused this catchpoint to trigger. That
2933 gives the user a more useful vantage from which to
2934 examine their program's state. */
2935 else if (what
.main_action
2936 == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
)
2938 /* ??rehrauer: If I could figure out how to get the
2939 right return PC from here, we could just set a temp
2940 breakpoint and resume. I'm not sure we can without
2941 cracking open the dld's shared libraries and sniffing
2942 their unwind tables and text/data ranges, and that's
2943 not a terribly portable notion.
2945 Until that time, we must step the inferior out of the
2946 dld callback, and also out of the dld itself (and any
2947 code or stubs in libdld.sl, such as "shl_load" and
2948 friends) until we reach non-dld code. At that point,
2949 we can stop stepping. */
2950 bpstat_get_triggered_catchpoints (stop_bpstat
,
2952 stepping_through_solib_catchpoints
);
2953 tss
->stepping_through_solib_after_catch
= 1;
2955 /* Be sure to lift all breakpoints, so the inferior does
2956 actually step past this point... */
2957 tss
->stepping_over_breakpoint
= 1;
2962 /* We want to step over this breakpoint, then keep going. */
2963 tss
->stepping_over_breakpoint
= 1;
2969 case BPSTAT_WHAT_LAST
:
2970 /* Not a real code, but listed here to shut up gcc -Wall. */
2972 case BPSTAT_WHAT_KEEP_CHECKING
:
2977 /* We come here if we hit a breakpoint but should not
2978 stop for it. Possibly we also were stepping
2979 and should stop for that. So fall through and
2980 test for stepping. But, if not stepping,
2983 /* Are we stepping to get the inferior out of the dynamic linker's
2984 hook (and possibly the dld itself) after catching a shlib
2986 if (tss
->stepping_through_solib_after_catch
)
2988 #if defined(SOLIB_ADD)
2989 /* Have we reached our destination? If not, keep going. */
2990 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
2993 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
2994 tss
->stepping_over_breakpoint
= 1;
3000 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
3001 /* Else, stop and report the catchpoint(s) whose triggering
3002 caused us to begin stepping. */
3003 tss
->stepping_through_solib_after_catch
= 0;
3004 bpstat_clear (&stop_bpstat
);
3005 stop_bpstat
= bpstat_copy (tss
->stepping_through_solib_catchpoints
);
3006 bpstat_clear (&tss
->stepping_through_solib_catchpoints
);
3007 stop_print_frame
= 1;
3008 stop_stepping (ecs
);
3012 if (step_resume_breakpoint
)
3015 fprintf_unfiltered (gdb_stdlog
,
3016 "infrun: step-resume breakpoint is inserted\n");
3018 /* Having a step-resume breakpoint overrides anything
3019 else having to do with stepping commands until
3020 that breakpoint is reached. */
3025 if (step_range_end
== 0)
3028 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
3029 /* Likewise if we aren't even stepping. */
3034 /* If stepping through a line, keep going if still within it.
3036 Note that step_range_end is the address of the first instruction
3037 beyond the step range, and NOT the address of the last instruction
3039 if (stop_pc
>= step_range_start
&& stop_pc
< step_range_end
)
3042 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping inside range [0x%s-0x%s]\n",
3043 paddr_nz (step_range_start
),
3044 paddr_nz (step_range_end
));
3049 /* We stepped out of the stepping range. */
3051 /* If we are stepping at the source level and entered the runtime
3052 loader dynamic symbol resolution code, we keep on single stepping
3053 until we exit the run time loader code and reach the callee's
3055 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3056 && in_solib_dynsym_resolve_code (stop_pc
))
3058 CORE_ADDR pc_after_resolver
=
3059 gdbarch_skip_solib_resolver (current_gdbarch
, stop_pc
);
3062 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
3064 if (pc_after_resolver
)
3066 /* Set up a step-resume breakpoint at the address
3067 indicated by SKIP_SOLIB_RESOLVER. */
3068 struct symtab_and_line sr_sal
;
3070 sr_sal
.pc
= pc_after_resolver
;
3072 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3079 if (step_range_end
!= 1
3080 && (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3081 || step_over_calls
== STEP_OVER_ALL
)
3082 && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME
)
3085 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
3086 /* The inferior, while doing a "step" or "next", has ended up in
3087 a signal trampoline (either by a signal being delivered or by
3088 the signal handler returning). Just single-step until the
3089 inferior leaves the trampoline (either by calling the handler
3095 /* Check for subroutine calls. The check for the current frame
3096 equalling the step ID is not necessary - the check of the
3097 previous frame's ID is sufficient - but it is a common case and
3098 cheaper than checking the previous frame's ID.
3100 NOTE: frame_id_eq will never report two invalid frame IDs as
3101 being equal, so to get into this block, both the current and
3102 previous frame must have valid frame IDs. */
3103 if (!frame_id_eq (get_frame_id (get_current_frame ()), step_frame_id
)
3104 && frame_id_eq (frame_unwind_id (get_current_frame ()), step_frame_id
))
3106 CORE_ADDR real_stop_pc
;
3109 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
3111 if ((step_over_calls
== STEP_OVER_NONE
)
3112 || ((step_range_end
== 1)
3113 && in_prologue (prev_pc
, ecs
->stop_func_start
)))
3115 /* I presume that step_over_calls is only 0 when we're
3116 supposed to be stepping at the assembly language level
3117 ("stepi"). Just stop. */
3118 /* Also, maybe we just did a "nexti" inside a prolog, so we
3119 thought it was a subroutine call but it was not. Stop as
3122 print_stop_reason (END_STEPPING_RANGE
, 0);
3123 stop_stepping (ecs
);
3127 if (step_over_calls
== STEP_OVER_ALL
)
3129 /* We're doing a "next", set a breakpoint at callee's return
3130 address (the address at which the caller will
3132 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3137 /* If we are in a function call trampoline (a stub between the
3138 calling routine and the real function), locate the real
3139 function. That's what tells us (a) whether we want to step
3140 into it at all, and (b) what prologue we want to run to the
3141 end of, if we do step into it. */
3142 real_stop_pc
= skip_language_trampoline (get_current_frame (), stop_pc
);
3143 if (real_stop_pc
== 0)
3144 real_stop_pc
= gdbarch_skip_trampoline_code
3145 (current_gdbarch
, get_current_frame (), stop_pc
);
3146 if (real_stop_pc
!= 0)
3147 ecs
->stop_func_start
= real_stop_pc
;
3149 if (in_solib_dynsym_resolve_code (ecs
->stop_func_start
))
3151 struct symtab_and_line sr_sal
;
3153 sr_sal
.pc
= ecs
->stop_func_start
;
3155 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3160 /* If we have line number information for the function we are
3161 thinking of stepping into, step into it.
3163 If there are several symtabs at that PC (e.g. with include
3164 files), just want to know whether *any* of them have line
3165 numbers. find_pc_line handles this. */
3167 struct symtab_and_line tmp_sal
;
3169 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3170 if (tmp_sal
.line
!= 0)
3172 step_into_function (ecs
);
3177 /* If we have no line number and the step-stop-if-no-debug is
3178 set, we stop the step so that the user has a chance to switch
3179 in assembly mode. */
3180 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
&& step_stop_if_no_debug
)
3183 print_stop_reason (END_STEPPING_RANGE
, 0);
3184 stop_stepping (ecs
);
3188 /* Set a breakpoint at callee's return address (the address at
3189 which the caller will resume). */
3190 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3195 /* If we're in the return path from a shared library trampoline,
3196 we want to proceed through the trampoline when stepping. */
3197 if (gdbarch_in_solib_return_trampoline (current_gdbarch
,
3198 stop_pc
, ecs
->stop_func_name
))
3200 /* Determine where this trampoline returns. */
3201 CORE_ADDR real_stop_pc
;
3202 real_stop_pc
= gdbarch_skip_trampoline_code
3203 (current_gdbarch
, get_current_frame (), stop_pc
);
3206 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
3208 /* Only proceed through if we know where it's going. */
3211 /* And put the step-breakpoint there and go until there. */
3212 struct symtab_and_line sr_sal
;
3214 init_sal (&sr_sal
); /* initialize to zeroes */
3215 sr_sal
.pc
= real_stop_pc
;
3216 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3218 /* Do not specify what the fp should be when we stop since
3219 on some machines the prologue is where the new fp value
3221 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3223 /* Restart without fiddling with the step ranges or
3230 stop_pc_sal
= find_pc_line (stop_pc
, 0);
3232 /* NOTE: tausq/2004-05-24: This if block used to be done before all
3233 the trampoline processing logic, however, there are some trampolines
3234 that have no names, so we should do trampoline handling first. */
3235 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3236 && ecs
->stop_func_name
== NULL
3237 && stop_pc_sal
.line
== 0)
3240 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
3242 /* The inferior just stepped into, or returned to, an
3243 undebuggable function (where there is no debugging information
3244 and no line number corresponding to the address where the
3245 inferior stopped). Since we want to skip this kind of code,
3246 we keep going until the inferior returns from this
3247 function - unless the user has asked us not to (via
3248 set step-mode) or we no longer know how to get back
3249 to the call site. */
3250 if (step_stop_if_no_debug
3251 || !frame_id_p (frame_unwind_id (get_current_frame ())))
3253 /* If we have no line number and the step-stop-if-no-debug
3254 is set, we stop the step so that the user has a chance to
3255 switch in assembly mode. */
3257 print_stop_reason (END_STEPPING_RANGE
, 0);
3258 stop_stepping (ecs
);
3263 /* Set a breakpoint at callee's return address (the address
3264 at which the caller will resume). */
3265 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3271 if (step_range_end
== 1)
3273 /* It is stepi or nexti. We always want to stop stepping after
3276 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
3278 print_stop_reason (END_STEPPING_RANGE
, 0);
3279 stop_stepping (ecs
);
3283 if (stop_pc_sal
.line
== 0)
3285 /* We have no line number information. That means to stop
3286 stepping (does this always happen right after one instruction,
3287 when we do "s" in a function with no line numbers,
3288 or can this happen as a result of a return or longjmp?). */
3290 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
3292 print_stop_reason (END_STEPPING_RANGE
, 0);
3293 stop_stepping (ecs
);
3297 if ((stop_pc
== stop_pc_sal
.pc
)
3298 && (tss
->current_line
!= stop_pc_sal
.line
3299 || tss
->current_symtab
!= stop_pc_sal
.symtab
))
3301 /* We are at the start of a different line. So stop. Note that
3302 we don't stop if we step into the middle of a different line.
3303 That is said to make things like for (;;) statements work
3306 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
3308 print_stop_reason (END_STEPPING_RANGE
, 0);
3309 stop_stepping (ecs
);
3313 /* We aren't done stepping.
3315 Optimize by setting the stepping range to the line.
3316 (We might not be in the original line, but if we entered a
3317 new line in mid-statement, we continue stepping. This makes
3318 things like for(;;) statements work better.) */
3320 step_range_start
= stop_pc_sal
.pc
;
3321 step_range_end
= stop_pc_sal
.end
;
3322 step_frame_id
= get_frame_id (get_current_frame ());
3323 tss
->current_line
= stop_pc_sal
.line
;
3324 tss
->current_symtab
= stop_pc_sal
.symtab
;
3326 /* In the case where we just stepped out of a function into the
3327 middle of a line of the caller, continue stepping, but
3328 step_frame_id must be modified to current frame */
3330 /* NOTE: cagney/2003-10-16: I think this frame ID inner test is too
3331 generous. It will trigger on things like a step into a frameless
3332 stackless leaf function. I think the logic should instead look
3333 at the unwound frame ID has that should give a more robust
3334 indication of what happened. */
3335 if (step
- ID
== current
- ID
)
3336 still stepping in same function
;
3337 else if (step
- ID
== unwind (current
- ID
))
3338 stepped into a function
;
3340 stepped out of a function
;
3341 /* Of course this assumes that the frame ID unwind code is robust
3342 and we're willing to introduce frame unwind logic into this
3343 function. Fortunately, those days are nearly upon us. */
3346 struct frame_info
*frame
= get_current_frame ();
3347 struct frame_id current_frame
= get_frame_id (frame
);
3348 if (!(frame_id_inner (get_frame_arch (frame
), current_frame
,
3350 step_frame_id
= current_frame
;
3354 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
3358 /* Are we in the middle of stepping? */
3361 currently_stepping (struct thread_stepping_state
*tss
)
3363 return (((step_range_end
&& step_resume_breakpoint
== NULL
)
3364 || stepping_over_breakpoint
)
3365 || tss
->stepping_through_solib_after_catch
3366 || bpstat_should_step ());
3369 /* Subroutine call with source code we should not step over. Do step
3370 to the first line of code in it. */
3373 step_into_function (struct execution_control_state
*ecs
)
3376 struct symtab_and_line stop_func_sal
, sr_sal
;
3378 s
= find_pc_symtab (stop_pc
);
3379 if (s
&& s
->language
!= language_asm
)
3380 ecs
->stop_func_start
= gdbarch_skip_prologue
3381 (current_gdbarch
, ecs
->stop_func_start
);
3383 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3384 /* Use the step_resume_break to step until the end of the prologue,
3385 even if that involves jumps (as it seems to on the vax under
3387 /* If the prologue ends in the middle of a source line, continue to
3388 the end of that source line (if it is still within the function).
3389 Otherwise, just go to end of prologue. */
3390 if (stop_func_sal
.end
3391 && stop_func_sal
.pc
!= ecs
->stop_func_start
3392 && stop_func_sal
.end
< ecs
->stop_func_end
)
3393 ecs
->stop_func_start
= stop_func_sal
.end
;
3395 /* Architectures which require breakpoint adjustment might not be able
3396 to place a breakpoint at the computed address. If so, the test
3397 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
3398 ecs->stop_func_start to an address at which a breakpoint may be
3399 legitimately placed.
3401 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
3402 made, GDB will enter an infinite loop when stepping through
3403 optimized code consisting of VLIW instructions which contain
3404 subinstructions corresponding to different source lines. On
3405 FR-V, it's not permitted to place a breakpoint on any but the
3406 first subinstruction of a VLIW instruction. When a breakpoint is
3407 set, GDB will adjust the breakpoint address to the beginning of
3408 the VLIW instruction. Thus, we need to make the corresponding
3409 adjustment here when computing the stop address. */
3411 if (gdbarch_adjust_breakpoint_address_p (current_gdbarch
))
3413 ecs
->stop_func_start
3414 = gdbarch_adjust_breakpoint_address (current_gdbarch
,
3415 ecs
->stop_func_start
);
3418 if (ecs
->stop_func_start
== stop_pc
)
3420 /* We are already there: stop now. */
3422 print_stop_reason (END_STEPPING_RANGE
, 0);
3423 stop_stepping (ecs
);
3428 /* Put the step-breakpoint there and go until there. */
3429 init_sal (&sr_sal
); /* initialize to zeroes */
3430 sr_sal
.pc
= ecs
->stop_func_start
;
3431 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
3433 /* Do not specify what the fp should be when we stop since on
3434 some machines the prologue is where the new fp value is
3436 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3438 /* And make sure stepping stops right away then. */
3439 step_range_end
= step_range_start
;
3444 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
3445 This is used to both functions and to skip over code. */
3448 insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
3449 struct frame_id sr_id
)
3451 /* There should never be more than one step-resume or longjmp-resume
3452 breakpoint per thread, so we should never be setting a new
3453 step_resume_breakpoint when one is already active. */
3454 gdb_assert (step_resume_breakpoint
== NULL
);
3457 fprintf_unfiltered (gdb_stdlog
,
3458 "infrun: inserting step-resume breakpoint at 0x%s\n",
3459 paddr_nz (sr_sal
.pc
));
3461 step_resume_breakpoint
= set_momentary_breakpoint (sr_sal
, sr_id
,
3465 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
3466 to skip a potential signal handler.
3468 This is called with the interrupted function's frame. The signal
3469 handler, when it returns, will resume the interrupted function at
3473 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
3475 struct symtab_and_line sr_sal
;
3477 gdb_assert (return_frame
!= NULL
);
3478 init_sal (&sr_sal
); /* initialize to zeros */
3480 sr_sal
.pc
= gdbarch_addr_bits_remove
3481 (current_gdbarch
, get_frame_pc (return_frame
));
3482 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3484 insert_step_resume_breakpoint_at_sal (sr_sal
, get_frame_id (return_frame
));
3487 /* Similar to insert_step_resume_breakpoint_at_frame, except
3488 but a breakpoint at the previous frame's PC. This is used to
3489 skip a function after stepping into it (for "next" or if the called
3490 function has no debugging information).
3492 The current function has almost always been reached by single
3493 stepping a call or return instruction. NEXT_FRAME belongs to the
3494 current function, and the breakpoint will be set at the caller's
3497 This is a separate function rather than reusing
3498 insert_step_resume_breakpoint_at_frame in order to avoid
3499 get_prev_frame, which may stop prematurely (see the implementation
3500 of frame_unwind_id for an example). */
3503 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
3505 struct symtab_and_line sr_sal
;
3507 /* We shouldn't have gotten here if we don't know where the call site
3509 gdb_assert (frame_id_p (frame_unwind_id (next_frame
)));
3511 init_sal (&sr_sal
); /* initialize to zeros */
3513 sr_sal
.pc
= gdbarch_addr_bits_remove
3514 (current_gdbarch
, frame_pc_unwind (next_frame
));
3515 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3517 insert_step_resume_breakpoint_at_sal (sr_sal
, frame_unwind_id (next_frame
));
3520 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
3521 new breakpoint at the target of a jmp_buf. The handling of
3522 longjmp-resume uses the same mechanisms used for handling
3523 "step-resume" breakpoints. */
3526 insert_longjmp_resume_breakpoint (CORE_ADDR pc
)
3528 /* There should never be more than one step-resume or longjmp-resume
3529 breakpoint per thread, so we should never be setting a new
3530 longjmp_resume_breakpoint when one is already active. */
3531 gdb_assert (step_resume_breakpoint
== NULL
);
3534 fprintf_unfiltered (gdb_stdlog
,
3535 "infrun: inserting longjmp-resume breakpoint at 0x%s\n",
3538 step_resume_breakpoint
=
3539 set_momentary_breakpoint_at_pc (pc
, bp_longjmp_resume
);
3543 stop_stepping (struct execution_control_state
*ecs
)
3546 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
3548 /* Let callers know we don't want to wait for the inferior anymore. */
3549 ecs
->wait_some_more
= 0;
3552 /* This function handles various cases where we need to continue
3553 waiting for the inferior. */
3554 /* (Used to be the keep_going: label in the old wait_for_inferior) */
3557 keep_going (struct execution_control_state
*ecs
)
3559 /* Save the pc before execution, to compare with pc after stop. */
3560 prev_pc
= read_pc (); /* Might have been DECR_AFTER_BREAK */
3562 /* If we did not do break;, it means we should keep running the
3563 inferior and not return to debugger. */
3565 if (stepping_over_breakpoint
&& stop_signal
!= TARGET_SIGNAL_TRAP
)
3567 /* We took a signal (which we are supposed to pass through to
3568 the inferior, else we'd have done a break above) and we
3569 haven't yet gotten our trap. Simply continue. */
3570 resume (currently_stepping (tss
), stop_signal
);
3574 /* Either the trap was not expected, but we are continuing
3575 anyway (the user asked that this signal be passed to the
3578 The signal was SIGTRAP, e.g. it was our signal, but we
3579 decided we should resume from it.
3581 We're going to run this baby now!
3583 Note that insert_breakpoints won't try to re-insert
3584 already inserted breakpoints. Therefore, we don't
3585 care if breakpoints were already inserted, or not. */
3587 if (tss
->stepping_over_breakpoint
)
3589 if (! use_displaced_stepping (current_gdbarch
))
3590 /* Since we can't do a displaced step, we have to remove
3591 the breakpoint while we step it. To keep things
3592 simple, we remove them all. */
3593 remove_breakpoints ();
3597 struct gdb_exception e
;
3598 /* Stop stepping when inserting breakpoints
3600 TRY_CATCH (e
, RETURN_MASK_ERROR
)
3602 insert_breakpoints ();
3606 stop_stepping (ecs
);
3611 stepping_over_breakpoint
= tss
->stepping_over_breakpoint
;
3613 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3614 specifies that such a signal should be delivered to the
3617 Typically, this would occure when a user is debugging a
3618 target monitor on a simulator: the target monitor sets a
3619 breakpoint; the simulator encounters this break-point and
3620 halts the simulation handing control to GDB; GDB, noteing
3621 that the break-point isn't valid, returns control back to the
3622 simulator; the simulator then delivers the hardware
3623 equivalent of a SIGNAL_TRAP to the program being debugged. */
3625 if (stop_signal
== TARGET_SIGNAL_TRAP
&& !signal_program
[stop_signal
])
3626 stop_signal
= TARGET_SIGNAL_0
;
3629 resume (currently_stepping (tss
), stop_signal
);
3632 prepare_to_wait (ecs
);
3635 /* This function normally comes after a resume, before
3636 handle_inferior_event exits. It takes care of any last bits of
3637 housekeeping, and sets the all-important wait_some_more flag. */
3640 prepare_to_wait (struct execution_control_state
*ecs
)
3643 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
3644 if (infwait_state
== infwait_normal_state
)
3646 overlay_cache_invalid
= 1;
3648 /* We have to invalidate the registers BEFORE calling
3649 target_wait because they can be loaded from the target while
3650 in target_wait. This makes remote debugging a bit more
3651 efficient for those targets that provide critical registers
3652 as part of their normal status mechanism. */
3654 registers_changed ();
3655 waiton_ptid
= pid_to_ptid (-1);
3657 /* This is the old end of the while loop. Let everybody know we
3658 want to wait for the inferior some more and get called again
3660 ecs
->wait_some_more
= 1;
3663 /* Print why the inferior has stopped. We always print something when
3664 the inferior exits, or receives a signal. The rest of the cases are
3665 dealt with later on in normal_stop() and print_it_typical(). Ideally
3666 there should be a call to this function from handle_inferior_event()
3667 each time stop_stepping() is called.*/
3669 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
3671 switch (stop_reason
)
3673 case END_STEPPING_RANGE
:
3674 /* We are done with a step/next/si/ni command. */
3675 /* For now print nothing. */
3676 /* Print a message only if not in the middle of doing a "step n"
3677 operation for n > 1 */
3678 if (!step_multi
|| !stop_step
)
3679 if (ui_out_is_mi_like_p (uiout
))
3682 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
3685 /* The inferior was terminated by a signal. */
3686 annotate_signalled ();
3687 if (ui_out_is_mi_like_p (uiout
))
3690 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
3691 ui_out_text (uiout
, "\nProgram terminated with signal ");
3692 annotate_signal_name ();
3693 ui_out_field_string (uiout
, "signal-name",
3694 target_signal_to_name (stop_info
));
3695 annotate_signal_name_end ();
3696 ui_out_text (uiout
, ", ");
3697 annotate_signal_string ();
3698 ui_out_field_string (uiout
, "signal-meaning",
3699 target_signal_to_string (stop_info
));
3700 annotate_signal_string_end ();
3701 ui_out_text (uiout
, ".\n");
3702 ui_out_text (uiout
, "The program no longer exists.\n");
3705 /* The inferior program is finished. */
3706 annotate_exited (stop_info
);
3709 if (ui_out_is_mi_like_p (uiout
))
3710 ui_out_field_string (uiout
, "reason",
3711 async_reason_lookup (EXEC_ASYNC_EXITED
));
3712 ui_out_text (uiout
, "\nProgram exited with code ");
3713 ui_out_field_fmt (uiout
, "exit-code", "0%o",
3714 (unsigned int) stop_info
);
3715 ui_out_text (uiout
, ".\n");
3719 if (ui_out_is_mi_like_p (uiout
))
3722 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
3723 ui_out_text (uiout
, "\nProgram exited normally.\n");
3725 /* Support the --return-child-result option. */
3726 return_child_result_value
= stop_info
;
3728 case SIGNAL_RECEIVED
:
3729 /* Signal received. The signal table tells us to print about
3732 ui_out_text (uiout
, "\nProgram received signal ");
3733 annotate_signal_name ();
3734 if (ui_out_is_mi_like_p (uiout
))
3736 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
3737 ui_out_field_string (uiout
, "signal-name",
3738 target_signal_to_name (stop_info
));
3739 annotate_signal_name_end ();
3740 ui_out_text (uiout
, ", ");
3741 annotate_signal_string ();
3742 ui_out_field_string (uiout
, "signal-meaning",
3743 target_signal_to_string (stop_info
));
3744 annotate_signal_string_end ();
3745 ui_out_text (uiout
, ".\n");
3748 internal_error (__FILE__
, __LINE__
,
3749 _("print_stop_reason: unrecognized enum value"));
3755 /* Here to return control to GDB when the inferior stops for real.
3756 Print appropriate messages, remove breakpoints, give terminal our modes.
3758 STOP_PRINT_FRAME nonzero means print the executing frame
3759 (pc, function, args, file, line number and line text).
3760 BREAKPOINTS_FAILED nonzero means stop was due to error
3761 attempting to insert breakpoints. */
3766 struct target_waitstatus last
;
3769 get_last_target_status (&last_ptid
, &last
);
3771 /* In non-stop mode, we don't want GDB to switch threads behind the
3772 user's back, to avoid races where the user is typing a command to
3773 apply to thread x, but GDB switches to thread y before the user
3774 finishes entering the command. */
3776 /* As with the notification of thread events, we want to delay
3777 notifying the user that we've switched thread context until
3778 the inferior actually stops.
3780 There's no point in saying anything if the inferior has exited.
3781 Note that SIGNALLED here means "exited with a signal", not
3782 "received a signal". */
3784 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
3785 && target_has_execution
3786 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3787 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3789 target_terminal_ours_for_output ();
3790 printf_filtered (_("[Switching to %s]\n"),
3791 target_pid_to_str (inferior_ptid
));
3792 annotate_thread_changed ();
3793 previous_inferior_ptid
= inferior_ptid
;
3796 /* NOTE drow/2004-01-17: Is this still necessary? */
3797 /* Make sure that the current_frame's pc is correct. This
3798 is a correction for setting up the frame info before doing
3799 gdbarch_decr_pc_after_break */
3800 if (target_has_execution
)
3801 /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
3802 gdbarch_decr_pc_after_break, the program counter can change. Ask the
3803 frame code to check for this and sort out any resultant mess.
3804 gdbarch_decr_pc_after_break needs to just go away. */
3805 deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
3807 if (!breakpoints_always_inserted_mode () && target_has_execution
)
3809 if (remove_breakpoints ())
3811 target_terminal_ours_for_output ();
3812 printf_filtered (_("\
3813 Cannot remove breakpoints because program is no longer writable.\n\
3814 It might be running in another process.\n\
3815 Further execution is probably impossible.\n"));
3819 /* If an auto-display called a function and that got a signal,
3820 delete that auto-display to avoid an infinite recursion. */
3822 if (stopped_by_random_signal
)
3823 disable_current_display ();
3825 /* Don't print a message if in the middle of doing a "step n"
3826 operation for n > 1 */
3827 if (step_multi
&& stop_step
)
3830 target_terminal_ours ();
3832 /* Set the current source location. This will also happen if we
3833 display the frame below, but the current SAL will be incorrect
3834 during a user hook-stop function. */
3835 if (target_has_stack
&& !stop_stack_dummy
)
3836 set_current_sal_from_frame (get_current_frame (), 1);
3838 /* Look up the hook_stop and run it (CLI internally handles problem
3839 of stop_command's pre-hook not existing). */
3841 catch_errors (hook_stop_stub
, stop_command
,
3842 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
3844 if (!target_has_stack
)
3850 /* Select innermost stack frame - i.e., current frame is frame 0,
3851 and current location is based on that.
3852 Don't do this on return from a stack dummy routine,
3853 or if the program has exited. */
3855 if (!stop_stack_dummy
)
3857 select_frame (get_current_frame ());
3859 /* Print current location without a level number, if
3860 we have changed functions or hit a breakpoint.
3861 Print source line if we have one.
3862 bpstat_print() contains the logic deciding in detail
3863 what to print, based on the event(s) that just occurred. */
3865 /* If --batch-silent is enabled then there's no need to print the current
3866 source location, and to try risks causing an error message about
3867 missing source files. */
3868 if (stop_print_frame
&& !batch_silent
)
3872 int do_frame_printing
= 1;
3874 bpstat_ret
= bpstat_print (stop_bpstat
);
3878 /* If we had hit a shared library event breakpoint,
3879 bpstat_print would print out this message. If we hit
3880 an OS-level shared library event, do the same
3882 if (last
.kind
== TARGET_WAITKIND_LOADED
)
3884 printf_filtered (_("Stopped due to shared library event\n"));
3885 source_flag
= SRC_LINE
; /* something bogus */
3886 do_frame_printing
= 0;
3890 /* FIXME: cagney/2002-12-01: Given that a frame ID does
3891 (or should) carry around the function and does (or
3892 should) use that when doing a frame comparison. */
3894 && frame_id_eq (step_frame_id
,
3895 get_frame_id (get_current_frame ()))
3896 && step_start_function
== find_pc_function (stop_pc
))
3897 source_flag
= SRC_LINE
; /* finished step, just print source line */
3899 source_flag
= SRC_AND_LOC
; /* print location and source line */
3901 case PRINT_SRC_AND_LOC
:
3902 source_flag
= SRC_AND_LOC
; /* print location and source line */
3904 case PRINT_SRC_ONLY
:
3905 source_flag
= SRC_LINE
;
3908 source_flag
= SRC_LINE
; /* something bogus */
3909 do_frame_printing
= 0;
3912 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
3915 if (ui_out_is_mi_like_p (uiout
))
3918 ui_out_field_int (uiout
, "thread-id",
3919 pid_to_thread_id (inferior_ptid
));
3922 struct cleanup
*back_to
= make_cleanup_ui_out_list_begin_end
3923 (uiout
, "stopped-threads");
3924 ui_out_field_int (uiout
, NULL
,
3925 pid_to_thread_id (inferior_ptid
));
3926 do_cleanups (back_to
);
3929 ui_out_field_string (uiout
, "stopped-threads", "all");
3931 /* The behavior of this routine with respect to the source
3933 SRC_LINE: Print only source line
3934 LOCATION: Print only location
3935 SRC_AND_LOC: Print location and source line */
3936 if (do_frame_printing
)
3937 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
3939 /* Display the auto-display expressions. */
3944 /* Save the function value return registers, if we care.
3945 We might be about to restore their previous contents. */
3946 if (proceed_to_finish
)
3948 /* This should not be necessary. */
3950 regcache_xfree (stop_registers
);
3952 /* NB: The copy goes through to the target picking up the value of
3953 all the registers. */
3954 stop_registers
= regcache_dup (get_current_regcache ());
3957 if (stop_stack_dummy
)
3959 /* Pop the empty frame that contains the stack dummy. POP_FRAME
3960 ends with a setting of the current frame, so we can use that
3962 frame_pop (get_current_frame ());
3963 /* Set stop_pc to what it was before we called the function.
3964 Can't rely on restore_inferior_status because that only gets
3965 called if we don't stop in the called function. */
3966 stop_pc
= read_pc ();
3967 select_frame (get_current_frame ());
3971 annotate_stopped ();
3972 if (!suppress_stop_observer
&& !step_multi
)
3973 observer_notify_normal_stop (stop_bpstat
);
3974 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3975 Delete any breakpoint that is to be deleted at the next stop. */
3976 breakpoint_auto_delete (stop_bpstat
);
3978 if (target_has_execution
3979 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3980 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3983 set_running (pid_to_ptid (-1), 0);
3985 set_running (inferior_ptid
, 0);
3990 hook_stop_stub (void *cmd
)
3992 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
3997 signal_stop_state (int signo
)
3999 /* Always stop on signals if we're just gaining control of the
4001 return signal_stop
[signo
] || stop_soon
!= NO_STOP_QUIETLY
;
4005 signal_print_state (int signo
)
4007 return signal_print
[signo
];
4011 signal_pass_state (int signo
)
4013 return signal_program
[signo
];
4017 signal_stop_update (int signo
, int state
)
4019 int ret
= signal_stop
[signo
];
4020 signal_stop
[signo
] = state
;
4025 signal_print_update (int signo
, int state
)
4027 int ret
= signal_print
[signo
];
4028 signal_print
[signo
] = state
;
4033 signal_pass_update (int signo
, int state
)
4035 int ret
= signal_program
[signo
];
4036 signal_program
[signo
] = state
;
4041 sig_print_header (void)
4043 printf_filtered (_("\
4044 Signal Stop\tPrint\tPass to program\tDescription\n"));
4048 sig_print_info (enum target_signal oursig
)
4050 char *name
= target_signal_to_name (oursig
);
4051 int name_padding
= 13 - strlen (name
);
4053 if (name_padding
<= 0)
4056 printf_filtered ("%s", name
);
4057 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
4058 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
4059 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
4060 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
4061 printf_filtered ("%s\n", target_signal_to_string (oursig
));
4064 /* Specify how various signals in the inferior should be handled. */
4067 handle_command (char *args
, int from_tty
)
4070 int digits
, wordlen
;
4071 int sigfirst
, signum
, siglast
;
4072 enum target_signal oursig
;
4075 unsigned char *sigs
;
4076 struct cleanup
*old_chain
;
4080 error_no_arg (_("signal to handle"));
4083 /* Allocate and zero an array of flags for which signals to handle. */
4085 nsigs
= (int) TARGET_SIGNAL_LAST
;
4086 sigs
= (unsigned char *) alloca (nsigs
);
4087 memset (sigs
, 0, nsigs
);
4089 /* Break the command line up into args. */
4091 argv
= buildargv (args
);
4096 old_chain
= make_cleanup_freeargv (argv
);
4098 /* Walk through the args, looking for signal oursigs, signal names, and
4099 actions. Signal numbers and signal names may be interspersed with
4100 actions, with the actions being performed for all signals cumulatively
4101 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
4103 while (*argv
!= NULL
)
4105 wordlen
= strlen (*argv
);
4106 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
4110 sigfirst
= siglast
= -1;
4112 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
4114 /* Apply action to all signals except those used by the
4115 debugger. Silently skip those. */
4118 siglast
= nsigs
- 1;
4120 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
4122 SET_SIGS (nsigs
, sigs
, signal_stop
);
4123 SET_SIGS (nsigs
, sigs
, signal_print
);
4125 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
4127 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4129 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
4131 SET_SIGS (nsigs
, sigs
, signal_print
);
4133 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
4135 SET_SIGS (nsigs
, sigs
, signal_program
);
4137 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
4139 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4141 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
4143 SET_SIGS (nsigs
, sigs
, signal_program
);
4145 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
4147 UNSET_SIGS (nsigs
, sigs
, signal_print
);
4148 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4150 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
4152 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4154 else if (digits
> 0)
4156 /* It is numeric. The numeric signal refers to our own
4157 internal signal numbering from target.h, not to host/target
4158 signal number. This is a feature; users really should be
4159 using symbolic names anyway, and the common ones like
4160 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
4162 sigfirst
= siglast
= (int)
4163 target_signal_from_command (atoi (*argv
));
4164 if ((*argv
)[digits
] == '-')
4167 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
4169 if (sigfirst
> siglast
)
4171 /* Bet he didn't figure we'd think of this case... */
4179 oursig
= target_signal_from_name (*argv
);
4180 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
4182 sigfirst
= siglast
= (int) oursig
;
4186 /* Not a number and not a recognized flag word => complain. */
4187 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
4191 /* If any signal numbers or symbol names were found, set flags for
4192 which signals to apply actions to. */
4194 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
4196 switch ((enum target_signal
) signum
)
4198 case TARGET_SIGNAL_TRAP
:
4199 case TARGET_SIGNAL_INT
:
4200 if (!allsigs
&& !sigs
[signum
])
4202 if (query ("%s is used by the debugger.\n\
4203 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal
) signum
)))
4209 printf_unfiltered (_("Not confirmed, unchanged.\n"));
4210 gdb_flush (gdb_stdout
);
4214 case TARGET_SIGNAL_0
:
4215 case TARGET_SIGNAL_DEFAULT
:
4216 case TARGET_SIGNAL_UNKNOWN
:
4217 /* Make sure that "all" doesn't print these. */
4228 target_notice_signals (inferior_ptid
);
4232 /* Show the results. */
4233 sig_print_header ();
4234 for (signum
= 0; signum
< nsigs
; signum
++)
4238 sig_print_info (signum
);
4243 do_cleanups (old_chain
);
4247 xdb_handle_command (char *args
, int from_tty
)
4250 struct cleanup
*old_chain
;
4252 /* Break the command line up into args. */
4254 argv
= buildargv (args
);
4259 old_chain
= make_cleanup_freeargv (argv
);
4260 if (argv
[1] != (char *) NULL
)
4265 bufLen
= strlen (argv
[0]) + 20;
4266 argBuf
= (char *) xmalloc (bufLen
);
4270 enum target_signal oursig
;
4272 oursig
= target_signal_from_name (argv
[0]);
4273 memset (argBuf
, 0, bufLen
);
4274 if (strcmp (argv
[1], "Q") == 0)
4275 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4278 if (strcmp (argv
[1], "s") == 0)
4280 if (!signal_stop
[oursig
])
4281 sprintf (argBuf
, "%s %s", argv
[0], "stop");
4283 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
4285 else if (strcmp (argv
[1], "i") == 0)
4287 if (!signal_program
[oursig
])
4288 sprintf (argBuf
, "%s %s", argv
[0], "pass");
4290 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
4292 else if (strcmp (argv
[1], "r") == 0)
4294 if (!signal_print
[oursig
])
4295 sprintf (argBuf
, "%s %s", argv
[0], "print");
4297 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4303 handle_command (argBuf
, from_tty
);
4305 printf_filtered (_("Invalid signal handling flag.\n"));
4310 do_cleanups (old_chain
);
4313 /* Print current contents of the tables set by the handle command.
4314 It is possible we should just be printing signals actually used
4315 by the current target (but for things to work right when switching
4316 targets, all signals should be in the signal tables). */
4319 signals_info (char *signum_exp
, int from_tty
)
4321 enum target_signal oursig
;
4322 sig_print_header ();
4326 /* First see if this is a symbol name. */
4327 oursig
= target_signal_from_name (signum_exp
);
4328 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
4330 /* No, try numeric. */
4332 target_signal_from_command (parse_and_eval_long (signum_exp
));
4334 sig_print_info (oursig
);
4338 printf_filtered ("\n");
4339 /* These ugly casts brought to you by the native VAX compiler. */
4340 for (oursig
= TARGET_SIGNAL_FIRST
;
4341 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
4342 oursig
= (enum target_signal
) ((int) oursig
+ 1))
4346 if (oursig
!= TARGET_SIGNAL_UNKNOWN
4347 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
4348 sig_print_info (oursig
);
4351 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
4354 struct inferior_status
4356 enum target_signal stop_signal
;
4360 int stop_stack_dummy
;
4361 int stopped_by_random_signal
;
4362 int stepping_over_breakpoint
;
4363 CORE_ADDR step_range_start
;
4364 CORE_ADDR step_range_end
;
4365 struct frame_id step_frame_id
;
4366 enum step_over_calls_kind step_over_calls
;
4367 CORE_ADDR step_resume_break_address
;
4368 int stop_after_trap
;
4371 /* These are here because if call_function_by_hand has written some
4372 registers and then decides to call error(), we better not have changed
4374 struct regcache
*registers
;
4376 /* A frame unique identifier. */
4377 struct frame_id selected_frame_id
;
4379 int breakpoint_proceeded
;
4380 int restore_stack_info
;
4381 int proceed_to_finish
;
4385 write_inferior_status_register (struct inferior_status
*inf_status
, int regno
,
4388 int size
= register_size (current_gdbarch
, regno
);
4389 void *buf
= alloca (size
);
4390 store_signed_integer (buf
, size
, val
);
4391 regcache_raw_write (inf_status
->registers
, regno
, buf
);
4394 /* Save all of the information associated with the inferior<==>gdb
4395 connection. INF_STATUS is a pointer to a "struct inferior_status"
4396 (defined in inferior.h). */
4398 struct inferior_status
*
4399 save_inferior_status (int restore_stack_info
)
4401 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
4403 inf_status
->stop_signal
= stop_signal
;
4404 inf_status
->stop_pc
= stop_pc
;
4405 inf_status
->stop_step
= stop_step
;
4406 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
4407 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
4408 inf_status
->stepping_over_breakpoint
= stepping_over_breakpoint
;
4409 inf_status
->step_range_start
= step_range_start
;
4410 inf_status
->step_range_end
= step_range_end
;
4411 inf_status
->step_frame_id
= step_frame_id
;
4412 inf_status
->step_over_calls
= step_over_calls
;
4413 inf_status
->stop_after_trap
= stop_after_trap
;
4414 inf_status
->stop_soon
= stop_soon
;
4415 /* Save original bpstat chain here; replace it with copy of chain.
4416 If caller's caller is walking the chain, they'll be happier if we
4417 hand them back the original chain when restore_inferior_status is
4419 inf_status
->stop_bpstat
= stop_bpstat
;
4420 stop_bpstat
= bpstat_copy (stop_bpstat
);
4421 inf_status
->breakpoint_proceeded
= breakpoint_proceeded
;
4422 inf_status
->restore_stack_info
= restore_stack_info
;
4423 inf_status
->proceed_to_finish
= proceed_to_finish
;
4425 inf_status
->registers
= regcache_dup (get_current_regcache ());
4427 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
4432 restore_selected_frame (void *args
)
4434 struct frame_id
*fid
= (struct frame_id
*) args
;
4435 struct frame_info
*frame
;
4437 frame
= frame_find_by_id (*fid
);
4439 /* If inf_status->selected_frame_id is NULL, there was no previously
4443 warning (_("Unable to restore previously selected frame."));
4447 select_frame (frame
);
4453 restore_inferior_status (struct inferior_status
*inf_status
)
4455 stop_signal
= inf_status
->stop_signal
;
4456 stop_pc
= inf_status
->stop_pc
;
4457 stop_step
= inf_status
->stop_step
;
4458 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
4459 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
4460 stepping_over_breakpoint
= inf_status
->stepping_over_breakpoint
;
4461 step_range_start
= inf_status
->step_range_start
;
4462 step_range_end
= inf_status
->step_range_end
;
4463 step_frame_id
= inf_status
->step_frame_id
;
4464 step_over_calls
= inf_status
->step_over_calls
;
4465 stop_after_trap
= inf_status
->stop_after_trap
;
4466 stop_soon
= inf_status
->stop_soon
;
4467 bpstat_clear (&stop_bpstat
);
4468 stop_bpstat
= inf_status
->stop_bpstat
;
4469 breakpoint_proceeded
= inf_status
->breakpoint_proceeded
;
4470 proceed_to_finish
= inf_status
->proceed_to_finish
;
4472 /* The inferior can be gone if the user types "print exit(0)"
4473 (and perhaps other times). */
4474 if (target_has_execution
)
4475 /* NB: The register write goes through to the target. */
4476 regcache_cpy (get_current_regcache (), inf_status
->registers
);
4477 regcache_xfree (inf_status
->registers
);
4479 /* FIXME: If we are being called after stopping in a function which
4480 is called from gdb, we should not be trying to restore the
4481 selected frame; it just prints a spurious error message (The
4482 message is useful, however, in detecting bugs in gdb (like if gdb
4483 clobbers the stack)). In fact, should we be restoring the
4484 inferior status at all in that case? . */
4486 if (target_has_stack
&& inf_status
->restore_stack_info
)
4488 /* The point of catch_errors is that if the stack is clobbered,
4489 walking the stack might encounter a garbage pointer and
4490 error() trying to dereference it. */
4492 (restore_selected_frame
, &inf_status
->selected_frame_id
,
4493 "Unable to restore previously selected frame:\n",
4494 RETURN_MASK_ERROR
) == 0)
4495 /* Error in restoring the selected frame. Select the innermost
4497 select_frame (get_current_frame ());
4505 do_restore_inferior_status_cleanup (void *sts
)
4507 restore_inferior_status (sts
);
4511 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
4513 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
4517 discard_inferior_status (struct inferior_status
*inf_status
)
4519 /* See save_inferior_status for info on stop_bpstat. */
4520 bpstat_clear (&inf_status
->stop_bpstat
);
4521 regcache_xfree (inf_status
->registers
);
4526 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
4528 struct target_waitstatus last
;
4531 get_last_target_status (&last_ptid
, &last
);
4533 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
4536 if (!ptid_equal (last_ptid
, pid
))
4539 *child_pid
= last
.value
.related_pid
;
4544 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
4546 struct target_waitstatus last
;
4549 get_last_target_status (&last_ptid
, &last
);
4551 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
4554 if (!ptid_equal (last_ptid
, pid
))
4557 *child_pid
= last
.value
.related_pid
;
4562 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
4564 struct target_waitstatus last
;
4567 get_last_target_status (&last_ptid
, &last
);
4569 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
4572 if (!ptid_equal (last_ptid
, pid
))
4575 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
4579 /* Oft used ptids */
4581 ptid_t minus_one_ptid
;
4583 /* Create a ptid given the necessary PID, LWP, and TID components. */
4586 ptid_build (int pid
, long lwp
, long tid
)
4596 /* Create a ptid from just a pid. */
4599 pid_to_ptid (int pid
)
4601 return ptid_build (pid
, 0, 0);
4604 /* Fetch the pid (process id) component from a ptid. */
4607 ptid_get_pid (ptid_t ptid
)
4612 /* Fetch the lwp (lightweight process) component from a ptid. */
4615 ptid_get_lwp (ptid_t ptid
)
4620 /* Fetch the tid (thread id) component from a ptid. */
4623 ptid_get_tid (ptid_t ptid
)
4628 /* ptid_equal() is used to test equality of two ptids. */
4631 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
4633 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
4634 && ptid1
.tid
== ptid2
.tid
);
4637 /* restore_inferior_ptid() will be used by the cleanup machinery
4638 to restore the inferior_ptid value saved in a call to
4639 save_inferior_ptid(). */
4642 restore_inferior_ptid (void *arg
)
4644 ptid_t
*saved_ptid_ptr
= arg
;
4645 inferior_ptid
= *saved_ptid_ptr
;
4649 /* Save the value of inferior_ptid so that it may be restored by a
4650 later call to do_cleanups(). Returns the struct cleanup pointer
4651 needed for later doing the cleanup. */
4654 save_inferior_ptid (void)
4656 ptid_t
*saved_ptid_ptr
;
4658 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
4659 *saved_ptid_ptr
= inferior_ptid
;
4660 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
4665 static int non_stop_1
= 0;
4668 set_non_stop (char *args
, int from_tty
,
4669 struct cmd_list_element
*c
)
4671 if (target_has_execution
)
4673 non_stop_1
= non_stop
;
4674 error (_("Cannot change this setting while the inferior is running."));
4677 non_stop
= non_stop_1
;
4681 show_non_stop (struct ui_file
*file
, int from_tty
,
4682 struct cmd_list_element
*c
, const char *value
)
4684 fprintf_filtered (file
,
4685 _("Controlling the inferior in non-stop mode is %s.\n"),
4691 _initialize_infrun (void)
4695 struct cmd_list_element
*c
;
4697 add_info ("signals", signals_info
, _("\
4698 What debugger does when program gets various signals.\n\
4699 Specify a signal as argument to print info on that signal only."));
4700 add_info_alias ("handle", "signals", 0);
4702 add_com ("handle", class_run
, handle_command
, _("\
4703 Specify how to handle a signal.\n\
4704 Args are signals and actions to apply to those signals.\n\
4705 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4706 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4707 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4708 The special arg \"all\" is recognized to mean all signals except those\n\
4709 used by the debugger, typically SIGTRAP and SIGINT.\n\
4710 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4711 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4712 Stop means reenter debugger if this signal happens (implies print).\n\
4713 Print means print a message if this signal happens.\n\
4714 Pass means let program see this signal; otherwise program doesn't know.\n\
4715 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4716 Pass and Stop may be combined."));
4719 add_com ("lz", class_info
, signals_info
, _("\
4720 What debugger does when program gets various signals.\n\
4721 Specify a signal as argument to print info on that signal only."));
4722 add_com ("z", class_run
, xdb_handle_command
, _("\
4723 Specify how to handle a signal.\n\
4724 Args are signals and actions to apply to those signals.\n\
4725 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4726 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4727 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4728 The special arg \"all\" is recognized to mean all signals except those\n\
4729 used by the debugger, typically SIGTRAP and SIGINT.\n\
4730 Recognized actions include \"s\" (toggles between stop and nostop), \n\
4731 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4732 nopass), \"Q\" (noprint)\n\
4733 Stop means reenter debugger if this signal happens (implies print).\n\
4734 Print means print a message if this signal happens.\n\
4735 Pass means let program see this signal; otherwise program doesn't know.\n\
4736 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4737 Pass and Stop may be combined."));
4741 stop_command
= add_cmd ("stop", class_obscure
,
4742 not_just_help_class_command
, _("\
4743 There is no `stop' command, but you can set a hook on `stop'.\n\
4744 This allows you to set a list of commands to be run each time execution\n\
4745 of the program stops."), &cmdlist
);
4747 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
4748 Set inferior debugging."), _("\
4749 Show inferior debugging."), _("\
4750 When non-zero, inferior specific debugging is enabled."),
4753 &setdebuglist
, &showdebuglist
);
4755 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
4756 Set displaced stepping debugging."), _("\
4757 Show displaced stepping debugging."), _("\
4758 When non-zero, displaced stepping specific debugging is enabled."),
4760 show_debug_displaced
,
4761 &setdebuglist
, &showdebuglist
);
4763 add_setshow_boolean_cmd ("non-stop", no_class
,
4765 Set whether gdb controls the inferior in non-stop mode."), _("\
4766 Show whether gdb controls the inferior in non-stop mode."), _("\
4767 When debugging a multi-threaded program and this setting is\n\
4768 off (the default, also called all-stop mode), when one thread stops\n\
4769 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
4770 all other threads in the program while you interact with the thread of\n\
4771 interest. When you continue or step a thread, you can allow the other\n\
4772 threads to run, or have them remain stopped, but while you inspect any\n\
4773 thread's state, all threads stop.\n\
4775 In non-stop mode, when one thread stops, other threads can continue\n\
4776 to run freely. You'll be able to step each thread independently,\n\
4777 leave it stopped or free to run as needed."),
4783 numsigs
= (int) TARGET_SIGNAL_LAST
;
4784 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
4785 signal_print
= (unsigned char *)
4786 xmalloc (sizeof (signal_print
[0]) * numsigs
);
4787 signal_program
= (unsigned char *)
4788 xmalloc (sizeof (signal_program
[0]) * numsigs
);
4789 for (i
= 0; i
< numsigs
; i
++)
4792 signal_print
[i
] = 1;
4793 signal_program
[i
] = 1;
4796 /* Signals caused by debugger's own actions
4797 should not be given to the program afterwards. */
4798 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
4799 signal_program
[TARGET_SIGNAL_INT
] = 0;
4801 /* Signals that are not errors should not normally enter the debugger. */
4802 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
4803 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
4804 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
4805 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
4806 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
4807 signal_print
[TARGET_SIGNAL_PROF
] = 0;
4808 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
4809 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
4810 signal_stop
[TARGET_SIGNAL_IO
] = 0;
4811 signal_print
[TARGET_SIGNAL_IO
] = 0;
4812 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
4813 signal_print
[TARGET_SIGNAL_POLL
] = 0;
4814 signal_stop
[TARGET_SIGNAL_URG
] = 0;
4815 signal_print
[TARGET_SIGNAL_URG
] = 0;
4816 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
4817 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
4819 /* These signals are used internally by user-level thread
4820 implementations. (See signal(5) on Solaris.) Like the above
4821 signals, a healthy program receives and handles them as part of
4822 its normal operation. */
4823 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
4824 signal_print
[TARGET_SIGNAL_LWP
] = 0;
4825 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
4826 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
4827 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
4828 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
4830 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
4831 &stop_on_solib_events
, _("\
4832 Set stopping for shared library events."), _("\
4833 Show stopping for shared library events."), _("\
4834 If nonzero, gdb will give control to the user when the dynamic linker\n\
4835 notifies gdb of shared library events. The most common event of interest\n\
4836 to the user would be loading/unloading of a new library."),
4838 show_stop_on_solib_events
,
4839 &setlist
, &showlist
);
4841 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
4842 follow_fork_mode_kind_names
,
4843 &follow_fork_mode_string
, _("\
4844 Set debugger response to a program call of fork or vfork."), _("\
4845 Show debugger response to a program call of fork or vfork."), _("\
4846 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4847 parent - the original process is debugged after a fork\n\
4848 child - the new process is debugged after a fork\n\
4849 The unfollowed process will continue to run.\n\
4850 By default, the debugger will follow the parent process."),
4852 show_follow_fork_mode_string
,
4853 &setlist
, &showlist
);
4855 add_setshow_enum_cmd ("scheduler-locking", class_run
,
4856 scheduler_enums
, &scheduler_mode
, _("\
4857 Set mode for locking scheduler during execution."), _("\
4858 Show mode for locking scheduler during execution."), _("\
4859 off == no locking (threads may preempt at any time)\n\
4860 on == full locking (no thread except the current thread may run)\n\
4861 step == scheduler locked during every single-step operation.\n\
4862 In this mode, no other thread may run during a step command.\n\
4863 Other threads may run while stepping over a function call ('next')."),
4864 set_schedlock_func
, /* traps on target vector */
4865 show_scheduler_mode
,
4866 &setlist
, &showlist
);
4868 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
4869 Set mode of the step operation."), _("\
4870 Show mode of the step operation."), _("\
4871 When set, doing a step over a function without debug line information\n\
4872 will stop at the first instruction of that function. Otherwise, the\n\
4873 function is skipped and the step command stops at a different source line."),
4875 show_step_stop_if_no_debug
,
4876 &setlist
, &showlist
);
4878 add_setshow_boolean_cmd ("can-use-displaced-stepping", class_maintenance
,
4879 &can_use_displaced_stepping
, _("\
4880 Set debugger's willingness to use displaced stepping."), _("\
4881 Show debugger's willingness to use displaced stepping."), _("\
4882 If zero, gdb will not use displaced stepping to step over\n\
4883 breakpoints, even if such is supported by the target."),
4885 show_can_use_displaced_stepping
,
4886 &maintenance_set_cmdlist
,
4887 &maintenance_show_cmdlist
);
4889 /* ptid initializations */
4890 null_ptid
= ptid_build (0, 0, 0);
4891 minus_one_ptid
= ptid_build (-1, 0, 0);
4892 inferior_ptid
= null_ptid
;
4893 target_last_wait_ptid
= minus_one_ptid
;
4894 displaced_step_ptid
= null_ptid
;
4896 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);