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
= get_thread_regcache (ecs
->ptid
);
1754 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1755 CORE_ADDR breakpoint_pc
;
1757 /* If this target does not decrement the PC after breakpoints, then
1758 we have nothing to do. */
1759 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
1762 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
1763 we aren't, just return.
1765 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
1766 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
1767 implemented by software breakpoints should be handled through the normal
1770 NOTE drow/2004-01-31: On some targets, breakpoints may generate
1771 different signals (SIGILL or SIGEMT for instance), but it is less
1772 clear where the PC is pointing afterwards. It may not match
1773 gdbarch_decr_pc_after_break. I don't know any specific target that
1774 generates these signals at breakpoints (the code has been in GDB since at
1775 least 1992) so I can not guess how to handle them here.
1777 In earlier versions of GDB, a target with
1778 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
1779 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
1780 target with both of these set in GDB history, and it seems unlikely to be
1781 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
1783 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
1786 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1789 /* Find the location where (if we've hit a breakpoint) the
1790 breakpoint would be. */
1791 breakpoint_pc
= regcache_read_pc (regcache
)
1792 - gdbarch_decr_pc_after_break (gdbarch
);
1794 /* Check whether there actually is a software breakpoint inserted
1795 at that location. */
1796 if (software_breakpoint_inserted_here_p (breakpoint_pc
))
1798 /* When using hardware single-step, a SIGTRAP is reported for both
1799 a completed single-step and a software breakpoint. Need to
1800 differentiate between the two, as the latter needs adjusting
1801 but the former does not.
1803 The SIGTRAP can be due to a completed hardware single-step only if
1804 - we didn't insert software single-step breakpoints
1805 - the thread to be examined is still the current thread
1806 - this thread is currently being stepped
1808 If any of these events did not occur, we must have stopped due
1809 to hitting a software breakpoint, and have to back up to the
1812 As a special case, we could have hardware single-stepped a
1813 software breakpoint. In this case (prev_pc == breakpoint_pc),
1814 we also need to back up to the breakpoint address. */
1816 if (singlestep_breakpoints_inserted_p
1817 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
1818 || !currently_stepping (tss
)
1819 || prev_pc
== breakpoint_pc
)
1820 regcache_write_pc (regcache
, breakpoint_pc
);
1825 init_infwait_state (void)
1827 waiton_ptid
= pid_to_ptid (-1);
1828 infwait_state
= infwait_normal_state
;
1832 error_is_running (void)
1835 Cannot execute this command while the selected thread is running."));
1839 ensure_not_running (void)
1841 if (is_running (inferior_ptid
))
1842 error_is_running ();
1845 /* Given an execution control state that has been freshly filled in
1846 by an event from the inferior, figure out what it means and take
1847 appropriate action. */
1850 handle_inferior_event (struct execution_control_state
*ecs
)
1852 int sw_single_step_trap_p
= 0;
1853 int stopped_by_watchpoint
;
1854 int stepped_after_stopped_by_watchpoint
= 0;
1855 struct symtab_and_line stop_pc_sal
;
1857 breakpoint_retire_moribund ();
1859 /* Cache the last pid/waitstatus. */
1860 target_last_wait_ptid
= ecs
->ptid
;
1861 target_last_waitstatus
= ecs
->ws
;
1863 /* Always clear state belonging to the previous time we stopped. */
1864 stop_stack_dummy
= 0;
1866 adjust_pc_after_break (ecs
);
1868 reinit_frame_cache ();
1870 /* If it's a new process, add it to the thread database */
1872 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
1873 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
1874 && !in_thread_list (ecs
->ptid
));
1876 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1877 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
1878 add_thread (ecs
->ptid
);
1880 if (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
1882 /* Mark the non-executing threads accordingly. */
1884 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
1885 || ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
1886 set_executing (pid_to_ptid (-1), 0);
1888 set_executing (ecs
->ptid
, 0);
1891 switch (infwait_state
)
1893 case infwait_thread_hop_state
:
1895 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
1896 /* Cancel the waiton_ptid. */
1897 waiton_ptid
= pid_to_ptid (-1);
1900 case infwait_normal_state
:
1902 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
1905 case infwait_step_watch_state
:
1907 fprintf_unfiltered (gdb_stdlog
,
1908 "infrun: infwait_step_watch_state\n");
1910 stepped_after_stopped_by_watchpoint
= 1;
1913 case infwait_nonstep_watch_state
:
1915 fprintf_unfiltered (gdb_stdlog
,
1916 "infrun: infwait_nonstep_watch_state\n");
1917 insert_breakpoints ();
1919 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1920 handle things like signals arriving and other things happening
1921 in combination correctly? */
1922 stepped_after_stopped_by_watchpoint
= 1;
1926 internal_error (__FILE__
, __LINE__
, _("bad switch"));
1928 infwait_state
= infwait_normal_state
;
1930 switch (ecs
->ws
.kind
)
1932 case TARGET_WAITKIND_LOADED
:
1934 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
1935 /* Ignore gracefully during startup of the inferior, as it might
1936 be the shell which has just loaded some objects, otherwise
1937 add the symbols for the newly loaded objects. Also ignore at
1938 the beginning of an attach or remote session; we will query
1939 the full list of libraries once the connection is
1941 if (stop_soon
== NO_STOP_QUIETLY
)
1943 /* Check for any newly added shared libraries if we're
1944 supposed to be adding them automatically. Switch
1945 terminal for any messages produced by
1946 breakpoint_re_set. */
1947 target_terminal_ours_for_output ();
1948 /* NOTE: cagney/2003-11-25: Make certain that the target
1949 stack's section table is kept up-to-date. Architectures,
1950 (e.g., PPC64), use the section table to perform
1951 operations such as address => section name and hence
1952 require the table to contain all sections (including
1953 those found in shared libraries). */
1954 /* NOTE: cagney/2003-11-25: Pass current_target and not
1955 exec_ops to SOLIB_ADD. This is because current GDB is
1956 only tooled to propagate section_table changes out from
1957 the "current_target" (see target_resize_to_sections), and
1958 not up from the exec stratum. This, of course, isn't
1959 right. "infrun.c" should only interact with the
1960 exec/process stratum, instead relying on the target stack
1961 to propagate relevant changes (stop, section table
1962 changed, ...) up to other layers. */
1964 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
1966 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
1968 target_terminal_inferior ();
1970 /* If requested, stop when the dynamic linker notifies
1971 gdb of events. This allows the user to get control
1972 and place breakpoints in initializer routines for
1973 dynamically loaded objects (among other things). */
1974 if (stop_on_solib_events
)
1976 stop_stepping (ecs
);
1980 /* NOTE drow/2007-05-11: This might be a good place to check
1981 for "catch load". */
1984 /* If we are skipping through a shell, or through shared library
1985 loading that we aren't interested in, resume the program. If
1986 we're running the program normally, also resume. But stop if
1987 we're attaching or setting up a remote connection. */
1988 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
1990 /* Loading of shared libraries might have changed breakpoint
1991 addresses. Make sure new breakpoints are inserted. */
1992 if (stop_soon
== NO_STOP_QUIETLY
1993 && !breakpoints_always_inserted_mode ())
1994 insert_breakpoints ();
1995 resume (0, TARGET_SIGNAL_0
);
1996 prepare_to_wait (ecs
);
2002 case TARGET_WAITKIND_SPURIOUS
:
2004 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
2005 resume (0, TARGET_SIGNAL_0
);
2006 prepare_to_wait (ecs
);
2009 case TARGET_WAITKIND_EXITED
:
2011 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
2012 target_terminal_ours (); /* Must do this before mourn anyway */
2013 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
2015 /* Record the exit code in the convenience variable $_exitcode, so
2016 that the user can inspect this again later. */
2017 set_internalvar (lookup_internalvar ("_exitcode"),
2018 value_from_longest (builtin_type_int
,
2019 (LONGEST
) ecs
->ws
.value
.integer
));
2020 gdb_flush (gdb_stdout
);
2021 target_mourn_inferior ();
2022 singlestep_breakpoints_inserted_p
= 0;
2023 stop_print_frame
= 0;
2024 stop_stepping (ecs
);
2027 case TARGET_WAITKIND_SIGNALLED
:
2029 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2030 stop_print_frame
= 0;
2031 stop_signal
= ecs
->ws
.value
.sig
;
2032 target_terminal_ours (); /* Must do this before mourn anyway */
2034 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2035 reach here unless the inferior is dead. However, for years
2036 target_kill() was called here, which hints that fatal signals aren't
2037 really fatal on some systems. If that's true, then some changes
2039 target_mourn_inferior ();
2041 print_stop_reason (SIGNAL_EXITED
, stop_signal
);
2042 singlestep_breakpoints_inserted_p
= 0;
2043 stop_stepping (ecs
);
2046 /* The following are the only cases in which we keep going;
2047 the above cases end in a continue or goto. */
2048 case TARGET_WAITKIND_FORKED
:
2049 case TARGET_WAITKIND_VFORKED
:
2051 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2052 stop_signal
= TARGET_SIGNAL_TRAP
;
2053 pending_follow
.kind
= ecs
->ws
.kind
;
2055 pending_follow
.fork_event
.parent_pid
= ecs
->ptid
;
2056 pending_follow
.fork_event
.child_pid
= ecs
->ws
.value
.related_pid
;
2058 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2060 context_switch (ecs
->ptid
);
2061 reinit_frame_cache ();
2064 stop_pc
= read_pc ();
2066 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2068 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2070 /* If no catchpoint triggered for this, then keep going. */
2071 if (ecs
->random_signal
)
2073 stop_signal
= TARGET_SIGNAL_0
;
2077 goto process_event_stop_test
;
2079 case TARGET_WAITKIND_EXECD
:
2081 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
2082 stop_signal
= TARGET_SIGNAL_TRAP
;
2084 pending_follow
.execd_pathname
=
2085 savestring (ecs
->ws
.value
.execd_pathname
,
2086 strlen (ecs
->ws
.value
.execd_pathname
));
2088 /* This causes the eventpoints and symbol table to be reset. Must
2089 do this now, before trying to determine whether to stop. */
2090 follow_exec (inferior_ptid
, pending_follow
.execd_pathname
);
2091 xfree (pending_follow
.execd_pathname
);
2093 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2096 /* The breakpoints module may need to touch the inferior's
2097 memory. Switch to the (stopped) event ptid
2099 ptid_t saved_inferior_ptid
= inferior_ptid
;
2100 inferior_ptid
= ecs
->ptid
;
2102 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2104 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2105 inferior_ptid
= saved_inferior_ptid
;
2108 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2110 context_switch (ecs
->ptid
);
2111 reinit_frame_cache ();
2114 /* If no catchpoint triggered for this, then keep going. */
2115 if (ecs
->random_signal
)
2117 stop_signal
= TARGET_SIGNAL_0
;
2121 goto process_event_stop_test
;
2123 /* Be careful not to try to gather much state about a thread
2124 that's in a syscall. It's frequently a losing proposition. */
2125 case TARGET_WAITKIND_SYSCALL_ENTRY
:
2127 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2128 resume (0, TARGET_SIGNAL_0
);
2129 prepare_to_wait (ecs
);
2132 /* Before examining the threads further, step this thread to
2133 get it entirely out of the syscall. (We get notice of the
2134 event when the thread is just on the verge of exiting a
2135 syscall. Stepping one instruction seems to get it back
2137 case TARGET_WAITKIND_SYSCALL_RETURN
:
2139 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2140 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
);
2141 prepare_to_wait (ecs
);
2144 case TARGET_WAITKIND_STOPPED
:
2146 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
2147 stop_signal
= ecs
->ws
.value
.sig
;
2150 /* We had an event in the inferior, but we are not interested
2151 in handling it at this level. The lower layers have already
2152 done what needs to be done, if anything.
2154 One of the possible circumstances for this is when the
2155 inferior produces output for the console. The inferior has
2156 not stopped, and we are ignoring the event. Another possible
2157 circumstance is any event which the lower level knows will be
2158 reported multiple times without an intervening resume. */
2159 case TARGET_WAITKIND_IGNORE
:
2161 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2162 prepare_to_wait (ecs
);
2166 if (ecs
->new_thread_event
)
2169 /* Non-stop assumes that the target handles adding new threads
2170 to the thread list. */
2171 internal_error (__FILE__
, __LINE__
, "\
2172 targets should add new threads to the thread list themselves in non-stop mode.");
2174 /* We may want to consider not doing a resume here in order to
2175 give the user a chance to play with the new thread. It might
2176 be good to make that a user-settable option. */
2178 /* At this point, all threads are stopped (happens automatically
2179 in either the OS or the native code). Therefore we need to
2180 continue all threads in order to make progress. */
2182 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
2183 prepare_to_wait (ecs
);
2187 /* Do we need to clean up the state of a thread that has completed a
2188 displaced single-step? (Doing so usually affects the PC, so do
2189 it here, before we set stop_pc.) */
2190 displaced_step_fixup (ecs
->ptid
, stop_signal
);
2192 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2196 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = 0x%s\n",
2197 paddr_nz (stop_pc
));
2198 if (STOPPED_BY_WATCHPOINT (&ecs
->ws
))
2201 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
2203 if (target_stopped_data_address (¤t_target
, &addr
))
2204 fprintf_unfiltered (gdb_stdlog
,
2205 "infrun: stopped data address = 0x%s\n",
2208 fprintf_unfiltered (gdb_stdlog
,
2209 "infrun: (no data address available)\n");
2213 if (stepping_past_singlestep_breakpoint
)
2215 gdb_assert (singlestep_breakpoints_inserted_p
);
2216 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
2217 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
2219 stepping_past_singlestep_breakpoint
= 0;
2221 /* We've either finished single-stepping past the single-step
2222 breakpoint, or stopped for some other reason. It would be nice if
2223 we could tell, but we can't reliably. */
2224 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2227 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
2228 /* Pull the single step breakpoints out of the target. */
2229 remove_single_step_breakpoints ();
2230 singlestep_breakpoints_inserted_p
= 0;
2232 ecs
->random_signal
= 0;
2234 context_switch (saved_singlestep_ptid
);
2235 if (deprecated_context_hook
)
2236 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2238 resume (1, TARGET_SIGNAL_0
);
2239 prepare_to_wait (ecs
);
2244 stepping_past_singlestep_breakpoint
= 0;
2246 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
2248 /* In non-stop mode, there's never a deferred_step_ptid set. */
2249 gdb_assert (!non_stop
);
2251 /* If we stopped for some other reason than single-stepping, ignore
2252 the fact that we were supposed to switch back. */
2253 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2256 fprintf_unfiltered (gdb_stdlog
,
2257 "infrun: handling deferred step\n");
2259 /* Pull the single step breakpoints out of the target. */
2260 if (singlestep_breakpoints_inserted_p
)
2262 remove_single_step_breakpoints ();
2263 singlestep_breakpoints_inserted_p
= 0;
2266 /* Note: We do not call context_switch at this point, as the
2267 context is already set up for stepping the original thread. */
2268 switch_to_thread (deferred_step_ptid
);
2269 deferred_step_ptid
= null_ptid
;
2270 /* Suppress spurious "Switching to ..." message. */
2271 previous_inferior_ptid
= inferior_ptid
;
2273 resume (1, TARGET_SIGNAL_0
);
2274 prepare_to_wait (ecs
);
2278 deferred_step_ptid
= null_ptid
;
2281 /* See if a thread hit a thread-specific breakpoint that was meant for
2282 another thread. If so, then step that thread past the breakpoint,
2285 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2287 int thread_hop_needed
= 0;
2289 /* Check if a regular breakpoint has been hit before checking
2290 for a potential single step breakpoint. Otherwise, GDB will
2291 not see this breakpoint hit when stepping onto breakpoints. */
2292 if (regular_breakpoint_inserted_here_p (stop_pc
))
2294 ecs
->random_signal
= 0;
2295 if (!breakpoint_thread_match (stop_pc
, ecs
->ptid
))
2296 thread_hop_needed
= 1;
2298 else if (singlestep_breakpoints_inserted_p
)
2300 /* We have not context switched yet, so this should be true
2301 no matter which thread hit the singlestep breakpoint. */
2302 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
2304 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
2306 target_pid_to_str (ecs
->ptid
));
2308 ecs
->random_signal
= 0;
2309 /* The call to in_thread_list is necessary because PTIDs sometimes
2310 change when we go from single-threaded to multi-threaded. If
2311 the singlestep_ptid is still in the list, assume that it is
2312 really different from ecs->ptid. */
2313 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
2314 && in_thread_list (singlestep_ptid
))
2316 /* If the PC of the thread we were trying to single-step
2317 has changed, discard this event (which we were going
2318 to ignore anyway), and pretend we saw that thread
2319 trap. This prevents us continuously moving the
2320 single-step breakpoint forward, one instruction at a
2321 time. If the PC has changed, then the thread we were
2322 trying to single-step has trapped or been signalled,
2323 but the event has not been reported to GDB yet.
2325 There might be some cases where this loses signal
2326 information, if a signal has arrived at exactly the
2327 same time that the PC changed, but this is the best
2328 we can do with the information available. Perhaps we
2329 should arrange to report all events for all threads
2330 when they stop, or to re-poll the remote looking for
2331 this particular thread (i.e. temporarily enable
2334 CORE_ADDR new_singlestep_pc
2335 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
2337 if (new_singlestep_pc
!= singlestep_pc
)
2340 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
2341 " but expected thread advanced also\n");
2343 /* The current context still belongs to
2344 singlestep_ptid. Don't swap here, since that's
2345 the context we want to use. Just fudge our
2346 state and continue. */
2347 ecs
->ptid
= singlestep_ptid
;
2348 stop_pc
= new_singlestep_pc
;
2353 fprintf_unfiltered (gdb_stdlog
,
2354 "infrun: unexpected thread\n");
2356 thread_hop_needed
= 1;
2357 stepping_past_singlestep_breakpoint
= 1;
2358 saved_singlestep_ptid
= singlestep_ptid
;
2363 if (thread_hop_needed
)
2365 int remove_status
= 0;
2368 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
2370 /* Saw a breakpoint, but it was hit by the wrong thread.
2373 if (singlestep_breakpoints_inserted_p
)
2375 /* Pull the single step breakpoints out of the target. */
2376 remove_single_step_breakpoints ();
2377 singlestep_breakpoints_inserted_p
= 0;
2380 /* If the arch can displace step, don't remove the
2382 if (!use_displaced_stepping (current_gdbarch
))
2383 remove_status
= remove_breakpoints ();
2385 /* Did we fail to remove breakpoints? If so, try
2386 to set the PC past the bp. (There's at least
2387 one situation in which we can fail to remove
2388 the bp's: On HP-UX's that use ttrace, we can't
2389 change the address space of a vforking child
2390 process until the child exits (well, okay, not
2391 then either :-) or execs. */
2392 if (remove_status
!= 0)
2393 error (_("Cannot step over breakpoint hit in wrong thread"));
2396 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
2397 context_switch (ecs
->ptid
);
2401 /* Only need to require the next event from this
2402 thread in all-stop mode. */
2403 waiton_ptid
= ecs
->ptid
;
2404 infwait_state
= infwait_thread_hop_state
;
2407 tss
->stepping_over_breakpoint
= 1;
2409 registers_changed ();
2413 else if (singlestep_breakpoints_inserted_p
)
2415 sw_single_step_trap_p
= 1;
2416 ecs
->random_signal
= 0;
2420 ecs
->random_signal
= 1;
2422 /* See if something interesting happened to the non-current thread. If
2423 so, then switch to that thread. */
2424 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2427 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
2429 context_switch (ecs
->ptid
);
2431 if (deprecated_context_hook
)
2432 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2435 if (singlestep_breakpoints_inserted_p
)
2437 /* Pull the single step breakpoints out of the target. */
2438 remove_single_step_breakpoints ();
2439 singlestep_breakpoints_inserted_p
= 0;
2442 if (stepped_after_stopped_by_watchpoint
)
2443 stopped_by_watchpoint
= 0;
2445 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
2447 /* If necessary, step over this watchpoint. We'll be back to display
2449 if (stopped_by_watchpoint
2450 && (HAVE_STEPPABLE_WATCHPOINT
2451 || gdbarch_have_nonsteppable_watchpoint (current_gdbarch
)))
2453 /* At this point, we are stopped at an instruction which has
2454 attempted to write to a piece of memory under control of
2455 a watchpoint. The instruction hasn't actually executed
2456 yet. If we were to evaluate the watchpoint expression
2457 now, we would get the old value, and therefore no change
2458 would seem to have occurred.
2460 In order to make watchpoints work `right', we really need
2461 to complete the memory write, and then evaluate the
2462 watchpoint expression. We do this by single-stepping the
2465 It may not be necessary to disable the watchpoint to stop over
2466 it. For example, the PA can (with some kernel cooperation)
2467 single step over a watchpoint without disabling the watchpoint.
2469 It is far more common to need to disable a watchpoint to step
2470 the inferior over it. If we have non-steppable watchpoints,
2471 we must disable the current watchpoint; it's simplest to
2472 disable all watchpoints and breakpoints. */
2474 if (!HAVE_STEPPABLE_WATCHPOINT
)
2475 remove_breakpoints ();
2476 registers_changed ();
2477 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
); /* Single step */
2478 waiton_ptid
= ecs
->ptid
;
2479 if (HAVE_STEPPABLE_WATCHPOINT
)
2480 infwait_state
= infwait_step_watch_state
;
2482 infwait_state
= infwait_nonstep_watch_state
;
2483 prepare_to_wait (ecs
);
2487 ecs
->stop_func_start
= 0;
2488 ecs
->stop_func_end
= 0;
2489 ecs
->stop_func_name
= 0;
2490 /* Don't care about return value; stop_func_start and stop_func_name
2491 will both be 0 if it doesn't work. */
2492 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
2493 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
2494 ecs
->stop_func_start
2495 += gdbarch_deprecated_function_start_offset (current_gdbarch
);
2496 tss
->stepping_over_breakpoint
= 0;
2497 bpstat_clear (&stop_bpstat
);
2499 stop_print_frame
= 1;
2500 ecs
->random_signal
= 0;
2501 stopped_by_random_signal
= 0;
2503 if (stop_signal
== TARGET_SIGNAL_TRAP
2504 && stepping_over_breakpoint
2505 && gdbarch_single_step_through_delay_p (current_gdbarch
)
2506 && currently_stepping (tss
))
2508 /* We're trying to step off a breakpoint. Turns out that we're
2509 also on an instruction that needs to be stepped multiple
2510 times before it's been fully executing. E.g., architectures
2511 with a delay slot. It needs to be stepped twice, once for
2512 the instruction and once for the delay slot. */
2513 int step_through_delay
2514 = gdbarch_single_step_through_delay (current_gdbarch
,
2515 get_current_frame ());
2516 if (debug_infrun
&& step_through_delay
)
2517 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
2518 if (step_range_end
== 0 && step_through_delay
)
2520 /* The user issued a continue when stopped at a breakpoint.
2521 Set up for another trap and get out of here. */
2522 tss
->stepping_over_breakpoint
= 1;
2526 else if (step_through_delay
)
2528 /* The user issued a step when stopped at a breakpoint.
2529 Maybe we should stop, maybe we should not - the delay
2530 slot *might* correspond to a line of source. In any
2531 case, don't decide that here, just set
2532 ecs->stepping_over_breakpoint, making sure we
2533 single-step again before breakpoints are re-inserted. */
2534 tss
->stepping_over_breakpoint
= 1;
2538 /* Look at the cause of the stop, and decide what to do.
2539 The alternatives are:
2540 1) stop_stepping and return; to really stop and return to the debugger,
2541 2) keep_going and return to start up again
2542 (set tss->stepping_over_breakpoint to 1 to single step once)
2543 3) set ecs->random_signal to 1, and the decision between 1 and 2
2544 will be made according to the signal handling tables. */
2546 /* First, distinguish signals caused by the debugger from signals
2547 that have to do with the program's own actions. Note that
2548 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
2549 on the operating system version. Here we detect when a SIGILL or
2550 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
2551 something similar for SIGSEGV, since a SIGSEGV will be generated
2552 when we're trying to execute a breakpoint instruction on a
2553 non-executable stack. This happens for call dummy breakpoints
2554 for architectures like SPARC that place call dummies on the
2557 If we're doing a displaced step past a breakpoint, then the
2558 breakpoint is always inserted at the original instruction;
2559 non-standard signals can't be explained by the breakpoint. */
2560 if (stop_signal
== TARGET_SIGNAL_TRAP
2561 || (! stepping_over_breakpoint
2562 && breakpoint_inserted_here_p (stop_pc
)
2563 && (stop_signal
== TARGET_SIGNAL_ILL
2564 || stop_signal
== TARGET_SIGNAL_SEGV
2565 || stop_signal
== TARGET_SIGNAL_EMT
))
2566 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2567 || stop_soon
== STOP_QUIETLY_REMOTE
)
2569 if (stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
2572 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
2573 stop_print_frame
= 0;
2574 stop_stepping (ecs
);
2578 /* This is originated from start_remote(), start_inferior() and
2579 shared libraries hook functions. */
2580 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
2583 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
2584 stop_stepping (ecs
);
2588 /* This originates from attach_command(). We need to overwrite
2589 the stop_signal here, because some kernels don't ignore a
2590 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
2591 See more comments in inferior.h. On the other hand, if we
2592 get a non-SIGSTOP, report it to the user - assume the backend
2593 will handle the SIGSTOP if it should show up later.
2595 Also consider that the attach is complete when we see a
2596 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
2597 target extended-remote report it instead of a SIGSTOP
2598 (e.g. gdbserver). We already rely on SIGTRAP being our
2599 signal, so this is no exception. */
2600 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2601 && (stop_signal
== TARGET_SIGNAL_STOP
2602 || stop_signal
== TARGET_SIGNAL_TRAP
))
2604 stop_stepping (ecs
);
2605 stop_signal
= TARGET_SIGNAL_0
;
2609 /* See if there is a breakpoint at the current PC. */
2610 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2612 /* Following in case break condition called a
2614 stop_print_frame
= 1;
2616 /* NOTE: cagney/2003-03-29: These two checks for a random signal
2617 at one stage in the past included checks for an inferior
2618 function call's call dummy's return breakpoint. The original
2619 comment, that went with the test, read:
2621 ``End of a stack dummy. Some systems (e.g. Sony news) give
2622 another signal besides SIGTRAP, so check here as well as
2625 If someone ever tries to get get call dummys on a
2626 non-executable stack to work (where the target would stop
2627 with something like a SIGSEGV), then those tests might need
2628 to be re-instated. Given, however, that the tests were only
2629 enabled when momentary breakpoints were not being used, I
2630 suspect that it won't be the case.
2632 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
2633 be necessary for call dummies on a non-executable stack on
2636 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2638 = !(bpstat_explains_signal (stop_bpstat
)
2639 || stepping_over_breakpoint
2640 || (step_range_end
&& step_resume_breakpoint
== NULL
));
2643 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2644 if (!ecs
->random_signal
)
2645 stop_signal
= TARGET_SIGNAL_TRAP
;
2649 /* When we reach this point, we've pretty much decided
2650 that the reason for stopping must've been a random
2651 (unexpected) signal. */
2654 ecs
->random_signal
= 1;
2656 process_event_stop_test
:
2657 /* For the program's own signals, act according to
2658 the signal handling tables. */
2660 if (ecs
->random_signal
)
2662 /* Signal not for debugging purposes. */
2666 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n", stop_signal
);
2668 stopped_by_random_signal
= 1;
2670 if (signal_print
[stop_signal
])
2673 target_terminal_ours_for_output ();
2674 print_stop_reason (SIGNAL_RECEIVED
, stop_signal
);
2676 if (signal_stop_state (stop_signal
))
2678 stop_stepping (ecs
);
2681 /* If not going to stop, give terminal back
2682 if we took it away. */
2684 target_terminal_inferior ();
2686 /* Clear the signal if it should not be passed. */
2687 if (signal_program
[stop_signal
] == 0)
2688 stop_signal
= TARGET_SIGNAL_0
;
2690 if (prev_pc
== read_pc ()
2691 && stepping_over_breakpoint
2692 && step_resume_breakpoint
== NULL
)
2694 /* We were just starting a new sequence, attempting to
2695 single-step off of a breakpoint and expecting a SIGTRAP.
2696 Instead this signal arrives. This signal will take us out
2697 of the stepping range so GDB needs to remember to, when
2698 the signal handler returns, resume stepping off that
2700 /* To simplify things, "continue" is forced to use the same
2701 code paths as single-step - set a breakpoint at the
2702 signal return address and then, once hit, step off that
2705 fprintf_unfiltered (gdb_stdlog
,
2706 "infrun: signal arrived while stepping over "
2709 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2710 tss
->step_after_step_resume_breakpoint
= 1;
2715 if (step_range_end
!= 0
2716 && stop_signal
!= TARGET_SIGNAL_0
2717 && stop_pc
>= step_range_start
&& stop_pc
< step_range_end
2718 && frame_id_eq (get_frame_id (get_current_frame ()),
2720 && step_resume_breakpoint
== NULL
)
2722 /* The inferior is about to take a signal that will take it
2723 out of the single step range. Set a breakpoint at the
2724 current PC (which is presumably where the signal handler
2725 will eventually return) and then allow the inferior to
2728 Note that this is only needed for a signal delivered
2729 while in the single-step range. Nested signals aren't a
2730 problem as they eventually all return. */
2732 fprintf_unfiltered (gdb_stdlog
,
2733 "infrun: signal may take us out of "
2734 "single-step range\n");
2736 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2741 /* Note: step_resume_breakpoint may be non-NULL. This occures
2742 when either there's a nested signal, or when there's a
2743 pending signal enabled just as the signal handler returns
2744 (leaving the inferior at the step-resume-breakpoint without
2745 actually executing it). Either way continue until the
2746 breakpoint is really hit. */
2751 /* Handle cases caused by hitting a breakpoint. */
2753 CORE_ADDR jmp_buf_pc
;
2754 struct bpstat_what what
;
2756 what
= bpstat_what (stop_bpstat
);
2758 if (what
.call_dummy
)
2760 stop_stack_dummy
= 1;
2763 switch (what
.main_action
)
2765 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
2766 /* If we hit the breakpoint at longjmp while stepping, we
2767 install a momentary breakpoint at the target of the
2771 fprintf_unfiltered (gdb_stdlog
,
2772 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
2774 tss
->stepping_over_breakpoint
= 1;
2776 if (!gdbarch_get_longjmp_target_p (current_gdbarch
)
2777 || !gdbarch_get_longjmp_target (current_gdbarch
,
2778 get_current_frame (), &jmp_buf_pc
))
2781 fprintf_unfiltered (gdb_stdlog
, "\
2782 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
2787 /* We're going to replace the current step-resume breakpoint
2788 with a longjmp-resume breakpoint. */
2789 if (step_resume_breakpoint
!= NULL
)
2790 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2792 /* Insert a breakpoint at resume address. */
2793 insert_longjmp_resume_breakpoint (jmp_buf_pc
);
2798 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
2800 fprintf_unfiltered (gdb_stdlog
,
2801 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
2803 gdb_assert (step_resume_breakpoint
!= NULL
);
2804 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2807 print_stop_reason (END_STEPPING_RANGE
, 0);
2808 stop_stepping (ecs
);
2811 case BPSTAT_WHAT_SINGLE
:
2813 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
2814 tss
->stepping_over_breakpoint
= 1;
2815 /* Still need to check other stuff, at least the case
2816 where we are stepping and step out of the right range. */
2819 case BPSTAT_WHAT_STOP_NOISY
:
2821 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
2822 stop_print_frame
= 1;
2824 /* We are about to nuke the step_resume_breakpointt via the
2825 cleanup chain, so no need to worry about it here. */
2827 stop_stepping (ecs
);
2830 case BPSTAT_WHAT_STOP_SILENT
:
2832 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
2833 stop_print_frame
= 0;
2835 /* We are about to nuke the step_resume_breakpoin via the
2836 cleanup chain, so no need to worry about it here. */
2838 stop_stepping (ecs
);
2841 case BPSTAT_WHAT_STEP_RESUME
:
2842 /* This proably demands a more elegant solution, but, yeah
2845 This function's use of the simple variable
2846 step_resume_breakpoint doesn't seem to accomodate
2847 simultaneously active step-resume bp's, although the
2848 breakpoint list certainly can.
2850 If we reach here and step_resume_breakpoint is already
2851 NULL, then apparently we have multiple active
2852 step-resume bp's. We'll just delete the breakpoint we
2853 stopped at, and carry on.
2855 Correction: what the code currently does is delete a
2856 step-resume bp, but it makes no effort to ensure that
2857 the one deleted is the one currently stopped at. MVS */
2860 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
2862 if (step_resume_breakpoint
== NULL
)
2864 step_resume_breakpoint
=
2865 bpstat_find_step_resume_breakpoint (stop_bpstat
);
2867 delete_step_resume_breakpoint (&step_resume_breakpoint
);
2868 if (tss
->step_after_step_resume_breakpoint
)
2870 /* Back when the step-resume breakpoint was inserted, we
2871 were trying to single-step off a breakpoint. Go back
2873 tss
->step_after_step_resume_breakpoint
= 0;
2874 tss
->stepping_over_breakpoint
= 1;
2880 case BPSTAT_WHAT_CHECK_SHLIBS
:
2881 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
:
2884 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
2886 /* Check for any newly added shared libraries if we're
2887 supposed to be adding them automatically. Switch
2888 terminal for any messages produced by
2889 breakpoint_re_set. */
2890 target_terminal_ours_for_output ();
2891 /* NOTE: cagney/2003-11-25: Make certain that the target
2892 stack's section table is kept up-to-date. Architectures,
2893 (e.g., PPC64), use the section table to perform
2894 operations such as address => section name and hence
2895 require the table to contain all sections (including
2896 those found in shared libraries). */
2897 /* NOTE: cagney/2003-11-25: Pass current_target and not
2898 exec_ops to SOLIB_ADD. This is because current GDB is
2899 only tooled to propagate section_table changes out from
2900 the "current_target" (see target_resize_to_sections), and
2901 not up from the exec stratum. This, of course, isn't
2902 right. "infrun.c" should only interact with the
2903 exec/process stratum, instead relying on the target stack
2904 to propagate relevant changes (stop, section table
2905 changed, ...) up to other layers. */
2907 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2909 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2911 target_terminal_inferior ();
2913 /* If requested, stop when the dynamic linker notifies
2914 gdb of events. This allows the user to get control
2915 and place breakpoints in initializer routines for
2916 dynamically loaded objects (among other things). */
2917 if (stop_on_solib_events
|| stop_stack_dummy
)
2919 stop_stepping (ecs
);
2923 /* If we stopped due to an explicit catchpoint, then the
2924 (see above) call to SOLIB_ADD pulled in any symbols
2925 from a newly-loaded library, if appropriate.
2927 We do want the inferior to stop, but not where it is
2928 now, which is in the dynamic linker callback. Rather,
2929 we would like it stop in the user's program, just after
2930 the call that caused this catchpoint to trigger. That
2931 gives the user a more useful vantage from which to
2932 examine their program's state. */
2933 else if (what
.main_action
2934 == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
)
2936 /* ??rehrauer: If I could figure out how to get the
2937 right return PC from here, we could just set a temp
2938 breakpoint and resume. I'm not sure we can without
2939 cracking open the dld's shared libraries and sniffing
2940 their unwind tables and text/data ranges, and that's
2941 not a terribly portable notion.
2943 Until that time, we must step the inferior out of the
2944 dld callback, and also out of the dld itself (and any
2945 code or stubs in libdld.sl, such as "shl_load" and
2946 friends) until we reach non-dld code. At that point,
2947 we can stop stepping. */
2948 bpstat_get_triggered_catchpoints (stop_bpstat
,
2950 stepping_through_solib_catchpoints
);
2951 tss
->stepping_through_solib_after_catch
= 1;
2953 /* Be sure to lift all breakpoints, so the inferior does
2954 actually step past this point... */
2955 tss
->stepping_over_breakpoint
= 1;
2960 /* We want to step over this breakpoint, then keep going. */
2961 tss
->stepping_over_breakpoint
= 1;
2967 case BPSTAT_WHAT_LAST
:
2968 /* Not a real code, but listed here to shut up gcc -Wall. */
2970 case BPSTAT_WHAT_KEEP_CHECKING
:
2975 /* We come here if we hit a breakpoint but should not
2976 stop for it. Possibly we also were stepping
2977 and should stop for that. So fall through and
2978 test for stepping. But, if not stepping,
2981 /* Are we stepping to get the inferior out of the dynamic linker's
2982 hook (and possibly the dld itself) after catching a shlib
2984 if (tss
->stepping_through_solib_after_catch
)
2986 #if defined(SOLIB_ADD)
2987 /* Have we reached our destination? If not, keep going. */
2988 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
2991 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
2992 tss
->stepping_over_breakpoint
= 1;
2998 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
2999 /* Else, stop and report the catchpoint(s) whose triggering
3000 caused us to begin stepping. */
3001 tss
->stepping_through_solib_after_catch
= 0;
3002 bpstat_clear (&stop_bpstat
);
3003 stop_bpstat
= bpstat_copy (tss
->stepping_through_solib_catchpoints
);
3004 bpstat_clear (&tss
->stepping_through_solib_catchpoints
);
3005 stop_print_frame
= 1;
3006 stop_stepping (ecs
);
3010 if (step_resume_breakpoint
)
3013 fprintf_unfiltered (gdb_stdlog
,
3014 "infrun: step-resume breakpoint is inserted\n");
3016 /* Having a step-resume breakpoint overrides anything
3017 else having to do with stepping commands until
3018 that breakpoint is reached. */
3023 if (step_range_end
== 0)
3026 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
3027 /* Likewise if we aren't even stepping. */
3032 /* If stepping through a line, keep going if still within it.
3034 Note that step_range_end is the address of the first instruction
3035 beyond the step range, and NOT the address of the last instruction
3037 if (stop_pc
>= step_range_start
&& stop_pc
< step_range_end
)
3040 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping inside range [0x%s-0x%s]\n",
3041 paddr_nz (step_range_start
),
3042 paddr_nz (step_range_end
));
3047 /* We stepped out of the stepping range. */
3049 /* If we are stepping at the source level and entered the runtime
3050 loader dynamic symbol resolution code, we keep on single stepping
3051 until we exit the run time loader code and reach the callee's
3053 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3054 && in_solib_dynsym_resolve_code (stop_pc
))
3056 CORE_ADDR pc_after_resolver
=
3057 gdbarch_skip_solib_resolver (current_gdbarch
, stop_pc
);
3060 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
3062 if (pc_after_resolver
)
3064 /* Set up a step-resume breakpoint at the address
3065 indicated by SKIP_SOLIB_RESOLVER. */
3066 struct symtab_and_line sr_sal
;
3068 sr_sal
.pc
= pc_after_resolver
;
3070 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3077 if (step_range_end
!= 1
3078 && (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3079 || step_over_calls
== STEP_OVER_ALL
)
3080 && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME
)
3083 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
3084 /* The inferior, while doing a "step" or "next", has ended up in
3085 a signal trampoline (either by a signal being delivered or by
3086 the signal handler returning). Just single-step until the
3087 inferior leaves the trampoline (either by calling the handler
3093 /* Check for subroutine calls. The check for the current frame
3094 equalling the step ID is not necessary - the check of the
3095 previous frame's ID is sufficient - but it is a common case and
3096 cheaper than checking the previous frame's ID.
3098 NOTE: frame_id_eq will never report two invalid frame IDs as
3099 being equal, so to get into this block, both the current and
3100 previous frame must have valid frame IDs. */
3101 if (!frame_id_eq (get_frame_id (get_current_frame ()), step_frame_id
)
3102 && frame_id_eq (frame_unwind_id (get_current_frame ()), step_frame_id
))
3104 CORE_ADDR real_stop_pc
;
3107 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
3109 if ((step_over_calls
== STEP_OVER_NONE
)
3110 || ((step_range_end
== 1)
3111 && in_prologue (prev_pc
, ecs
->stop_func_start
)))
3113 /* I presume that step_over_calls is only 0 when we're
3114 supposed to be stepping at the assembly language level
3115 ("stepi"). Just stop. */
3116 /* Also, maybe we just did a "nexti" inside a prolog, so we
3117 thought it was a subroutine call but it was not. Stop as
3120 print_stop_reason (END_STEPPING_RANGE
, 0);
3121 stop_stepping (ecs
);
3125 if (step_over_calls
== STEP_OVER_ALL
)
3127 /* We're doing a "next", set a breakpoint at callee's return
3128 address (the address at which the caller will
3130 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3135 /* If we are in a function call trampoline (a stub between the
3136 calling routine and the real function), locate the real
3137 function. That's what tells us (a) whether we want to step
3138 into it at all, and (b) what prologue we want to run to the
3139 end of, if we do step into it. */
3140 real_stop_pc
= skip_language_trampoline (get_current_frame (), stop_pc
);
3141 if (real_stop_pc
== 0)
3142 real_stop_pc
= gdbarch_skip_trampoline_code
3143 (current_gdbarch
, get_current_frame (), stop_pc
);
3144 if (real_stop_pc
!= 0)
3145 ecs
->stop_func_start
= real_stop_pc
;
3147 if (in_solib_dynsym_resolve_code (ecs
->stop_func_start
))
3149 struct symtab_and_line sr_sal
;
3151 sr_sal
.pc
= ecs
->stop_func_start
;
3153 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3158 /* If we have line number information for the function we are
3159 thinking of stepping into, step into it.
3161 If there are several symtabs at that PC (e.g. with include
3162 files), just want to know whether *any* of them have line
3163 numbers. find_pc_line handles this. */
3165 struct symtab_and_line tmp_sal
;
3167 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3168 if (tmp_sal
.line
!= 0)
3170 step_into_function (ecs
);
3175 /* If we have no line number and the step-stop-if-no-debug is
3176 set, we stop the step so that the user has a chance to switch
3177 in assembly mode. */
3178 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
&& step_stop_if_no_debug
)
3181 print_stop_reason (END_STEPPING_RANGE
, 0);
3182 stop_stepping (ecs
);
3186 /* Set a breakpoint at callee's return address (the address at
3187 which the caller will resume). */
3188 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3193 /* If we're in the return path from a shared library trampoline,
3194 we want to proceed through the trampoline when stepping. */
3195 if (gdbarch_in_solib_return_trampoline (current_gdbarch
,
3196 stop_pc
, ecs
->stop_func_name
))
3198 /* Determine where this trampoline returns. */
3199 CORE_ADDR real_stop_pc
;
3200 real_stop_pc
= gdbarch_skip_trampoline_code
3201 (current_gdbarch
, get_current_frame (), stop_pc
);
3204 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
3206 /* Only proceed through if we know where it's going. */
3209 /* And put the step-breakpoint there and go until there. */
3210 struct symtab_and_line sr_sal
;
3212 init_sal (&sr_sal
); /* initialize to zeroes */
3213 sr_sal
.pc
= real_stop_pc
;
3214 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3216 /* Do not specify what the fp should be when we stop since
3217 on some machines the prologue is where the new fp value
3219 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3221 /* Restart without fiddling with the step ranges or
3228 stop_pc_sal
= find_pc_line (stop_pc
, 0);
3230 /* NOTE: tausq/2004-05-24: This if block used to be done before all
3231 the trampoline processing logic, however, there are some trampolines
3232 that have no names, so we should do trampoline handling first. */
3233 if (step_over_calls
== STEP_OVER_UNDEBUGGABLE
3234 && ecs
->stop_func_name
== NULL
3235 && stop_pc_sal
.line
== 0)
3238 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
3240 /* The inferior just stepped into, or returned to, an
3241 undebuggable function (where there is no debugging information
3242 and no line number corresponding to the address where the
3243 inferior stopped). Since we want to skip this kind of code,
3244 we keep going until the inferior returns from this
3245 function - unless the user has asked us not to (via
3246 set step-mode) or we no longer know how to get back
3247 to the call site. */
3248 if (step_stop_if_no_debug
3249 || !frame_id_p (frame_unwind_id (get_current_frame ())))
3251 /* If we have no line number and the step-stop-if-no-debug
3252 is set, we stop the step so that the user has a chance to
3253 switch in assembly mode. */
3255 print_stop_reason (END_STEPPING_RANGE
, 0);
3256 stop_stepping (ecs
);
3261 /* Set a breakpoint at callee's return address (the address
3262 at which the caller will resume). */
3263 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3269 if (step_range_end
== 1)
3271 /* It is stepi or nexti. We always want to stop stepping after
3274 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
3276 print_stop_reason (END_STEPPING_RANGE
, 0);
3277 stop_stepping (ecs
);
3281 if (stop_pc_sal
.line
== 0)
3283 /* We have no line number information. That means to stop
3284 stepping (does this always happen right after one instruction,
3285 when we do "s" in a function with no line numbers,
3286 or can this happen as a result of a return or longjmp?). */
3288 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
3290 print_stop_reason (END_STEPPING_RANGE
, 0);
3291 stop_stepping (ecs
);
3295 if ((stop_pc
== stop_pc_sal
.pc
)
3296 && (tss
->current_line
!= stop_pc_sal
.line
3297 || tss
->current_symtab
!= stop_pc_sal
.symtab
))
3299 /* We are at the start of a different line. So stop. Note that
3300 we don't stop if we step into the middle of a different line.
3301 That is said to make things like for (;;) statements work
3304 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
3306 print_stop_reason (END_STEPPING_RANGE
, 0);
3307 stop_stepping (ecs
);
3311 /* We aren't done stepping.
3313 Optimize by setting the stepping range to the line.
3314 (We might not be in the original line, but if we entered a
3315 new line in mid-statement, we continue stepping. This makes
3316 things like for(;;) statements work better.) */
3318 step_range_start
= stop_pc_sal
.pc
;
3319 step_range_end
= stop_pc_sal
.end
;
3320 step_frame_id
= get_frame_id (get_current_frame ());
3321 tss
->current_line
= stop_pc_sal
.line
;
3322 tss
->current_symtab
= stop_pc_sal
.symtab
;
3324 /* In the case where we just stepped out of a function into the
3325 middle of a line of the caller, continue stepping, but
3326 step_frame_id must be modified to current frame */
3328 /* NOTE: cagney/2003-10-16: I think this frame ID inner test is too
3329 generous. It will trigger on things like a step into a frameless
3330 stackless leaf function. I think the logic should instead look
3331 at the unwound frame ID has that should give a more robust
3332 indication of what happened. */
3333 if (step
- ID
== current
- ID
)
3334 still stepping in same function
;
3335 else if (step
- ID
== unwind (current
- ID
))
3336 stepped into a function
;
3338 stepped out of a function
;
3339 /* Of course this assumes that the frame ID unwind code is robust
3340 and we're willing to introduce frame unwind logic into this
3341 function. Fortunately, those days are nearly upon us. */
3344 struct frame_info
*frame
= get_current_frame ();
3345 struct frame_id current_frame
= get_frame_id (frame
);
3346 if (!(frame_id_inner (get_frame_arch (frame
), current_frame
,
3348 step_frame_id
= current_frame
;
3352 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
3356 /* Are we in the middle of stepping? */
3359 currently_stepping (struct thread_stepping_state
*tss
)
3361 return (((step_range_end
&& step_resume_breakpoint
== NULL
)
3362 || stepping_over_breakpoint
)
3363 || tss
->stepping_through_solib_after_catch
3364 || bpstat_should_step ());
3367 /* Subroutine call with source code we should not step over. Do step
3368 to the first line of code in it. */
3371 step_into_function (struct execution_control_state
*ecs
)
3374 struct symtab_and_line stop_func_sal
, sr_sal
;
3376 s
= find_pc_symtab (stop_pc
);
3377 if (s
&& s
->language
!= language_asm
)
3378 ecs
->stop_func_start
= gdbarch_skip_prologue
3379 (current_gdbarch
, ecs
->stop_func_start
);
3381 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3382 /* Use the step_resume_break to step until the end of the prologue,
3383 even if that involves jumps (as it seems to on the vax under
3385 /* If the prologue ends in the middle of a source line, continue to
3386 the end of that source line (if it is still within the function).
3387 Otherwise, just go to end of prologue. */
3388 if (stop_func_sal
.end
3389 && stop_func_sal
.pc
!= ecs
->stop_func_start
3390 && stop_func_sal
.end
< ecs
->stop_func_end
)
3391 ecs
->stop_func_start
= stop_func_sal
.end
;
3393 /* Architectures which require breakpoint adjustment might not be able
3394 to place a breakpoint at the computed address. If so, the test
3395 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
3396 ecs->stop_func_start to an address at which a breakpoint may be
3397 legitimately placed.
3399 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
3400 made, GDB will enter an infinite loop when stepping through
3401 optimized code consisting of VLIW instructions which contain
3402 subinstructions corresponding to different source lines. On
3403 FR-V, it's not permitted to place a breakpoint on any but the
3404 first subinstruction of a VLIW instruction. When a breakpoint is
3405 set, GDB will adjust the breakpoint address to the beginning of
3406 the VLIW instruction. Thus, we need to make the corresponding
3407 adjustment here when computing the stop address. */
3409 if (gdbarch_adjust_breakpoint_address_p (current_gdbarch
))
3411 ecs
->stop_func_start
3412 = gdbarch_adjust_breakpoint_address (current_gdbarch
,
3413 ecs
->stop_func_start
);
3416 if (ecs
->stop_func_start
== stop_pc
)
3418 /* We are already there: stop now. */
3420 print_stop_reason (END_STEPPING_RANGE
, 0);
3421 stop_stepping (ecs
);
3426 /* Put the step-breakpoint there and go until there. */
3427 init_sal (&sr_sal
); /* initialize to zeroes */
3428 sr_sal
.pc
= ecs
->stop_func_start
;
3429 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
3431 /* Do not specify what the fp should be when we stop since on
3432 some machines the prologue is where the new fp value is
3434 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3436 /* And make sure stepping stops right away then. */
3437 step_range_end
= step_range_start
;
3442 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
3443 This is used to both functions and to skip over code. */
3446 insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
3447 struct frame_id sr_id
)
3449 /* There should never be more than one step-resume or longjmp-resume
3450 breakpoint per thread, so we should never be setting a new
3451 step_resume_breakpoint when one is already active. */
3452 gdb_assert (step_resume_breakpoint
== NULL
);
3455 fprintf_unfiltered (gdb_stdlog
,
3456 "infrun: inserting step-resume breakpoint at 0x%s\n",
3457 paddr_nz (sr_sal
.pc
));
3459 step_resume_breakpoint
= set_momentary_breakpoint (sr_sal
, sr_id
,
3463 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
3464 to skip a potential signal handler.
3466 This is called with the interrupted function's frame. The signal
3467 handler, when it returns, will resume the interrupted function at
3471 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
3473 struct symtab_and_line sr_sal
;
3475 gdb_assert (return_frame
!= NULL
);
3476 init_sal (&sr_sal
); /* initialize to zeros */
3478 sr_sal
.pc
= gdbarch_addr_bits_remove
3479 (current_gdbarch
, get_frame_pc (return_frame
));
3480 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3482 insert_step_resume_breakpoint_at_sal (sr_sal
, get_frame_id (return_frame
));
3485 /* Similar to insert_step_resume_breakpoint_at_frame, except
3486 but a breakpoint at the previous frame's PC. This is used to
3487 skip a function after stepping into it (for "next" or if the called
3488 function has no debugging information).
3490 The current function has almost always been reached by single
3491 stepping a call or return instruction. NEXT_FRAME belongs to the
3492 current function, and the breakpoint will be set at the caller's
3495 This is a separate function rather than reusing
3496 insert_step_resume_breakpoint_at_frame in order to avoid
3497 get_prev_frame, which may stop prematurely (see the implementation
3498 of frame_unwind_id for an example). */
3501 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
3503 struct symtab_and_line sr_sal
;
3505 /* We shouldn't have gotten here if we don't know where the call site
3507 gdb_assert (frame_id_p (frame_unwind_id (next_frame
)));
3509 init_sal (&sr_sal
); /* initialize to zeros */
3511 sr_sal
.pc
= gdbarch_addr_bits_remove
3512 (current_gdbarch
, frame_pc_unwind (next_frame
));
3513 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3515 insert_step_resume_breakpoint_at_sal (sr_sal
, frame_unwind_id (next_frame
));
3518 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
3519 new breakpoint at the target of a jmp_buf. The handling of
3520 longjmp-resume uses the same mechanisms used for handling
3521 "step-resume" breakpoints. */
3524 insert_longjmp_resume_breakpoint (CORE_ADDR pc
)
3526 /* There should never be more than one step-resume or longjmp-resume
3527 breakpoint per thread, so we should never be setting a new
3528 longjmp_resume_breakpoint when one is already active. */
3529 gdb_assert (step_resume_breakpoint
== NULL
);
3532 fprintf_unfiltered (gdb_stdlog
,
3533 "infrun: inserting longjmp-resume breakpoint at 0x%s\n",
3536 step_resume_breakpoint
=
3537 set_momentary_breakpoint_at_pc (pc
, bp_longjmp_resume
);
3541 stop_stepping (struct execution_control_state
*ecs
)
3544 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
3546 /* Let callers know we don't want to wait for the inferior anymore. */
3547 ecs
->wait_some_more
= 0;
3550 /* This function handles various cases where we need to continue
3551 waiting for the inferior. */
3552 /* (Used to be the keep_going: label in the old wait_for_inferior) */
3555 keep_going (struct execution_control_state
*ecs
)
3557 /* Save the pc before execution, to compare with pc after stop. */
3558 prev_pc
= read_pc (); /* Might have been DECR_AFTER_BREAK */
3560 /* If we did not do break;, it means we should keep running the
3561 inferior and not return to debugger. */
3563 if (stepping_over_breakpoint
&& stop_signal
!= TARGET_SIGNAL_TRAP
)
3565 /* We took a signal (which we are supposed to pass through to
3566 the inferior, else we'd have done a break above) and we
3567 haven't yet gotten our trap. Simply continue. */
3568 resume (currently_stepping (tss
), stop_signal
);
3572 /* Either the trap was not expected, but we are continuing
3573 anyway (the user asked that this signal be passed to the
3576 The signal was SIGTRAP, e.g. it was our signal, but we
3577 decided we should resume from it.
3579 We're going to run this baby now!
3581 Note that insert_breakpoints won't try to re-insert
3582 already inserted breakpoints. Therefore, we don't
3583 care if breakpoints were already inserted, or not. */
3585 if (tss
->stepping_over_breakpoint
)
3587 if (! use_displaced_stepping (current_gdbarch
))
3588 /* Since we can't do a displaced step, we have to remove
3589 the breakpoint while we step it. To keep things
3590 simple, we remove them all. */
3591 remove_breakpoints ();
3595 struct gdb_exception e
;
3596 /* Stop stepping when inserting breakpoints
3598 TRY_CATCH (e
, RETURN_MASK_ERROR
)
3600 insert_breakpoints ();
3604 stop_stepping (ecs
);
3609 stepping_over_breakpoint
= tss
->stepping_over_breakpoint
;
3611 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3612 specifies that such a signal should be delivered to the
3615 Typically, this would occure when a user is debugging a
3616 target monitor on a simulator: the target monitor sets a
3617 breakpoint; the simulator encounters this break-point and
3618 halts the simulation handing control to GDB; GDB, noteing
3619 that the break-point isn't valid, returns control back to the
3620 simulator; the simulator then delivers the hardware
3621 equivalent of a SIGNAL_TRAP to the program being debugged. */
3623 if (stop_signal
== TARGET_SIGNAL_TRAP
&& !signal_program
[stop_signal
])
3624 stop_signal
= TARGET_SIGNAL_0
;
3627 resume (currently_stepping (tss
), stop_signal
);
3630 prepare_to_wait (ecs
);
3633 /* This function normally comes after a resume, before
3634 handle_inferior_event exits. It takes care of any last bits of
3635 housekeeping, and sets the all-important wait_some_more flag. */
3638 prepare_to_wait (struct execution_control_state
*ecs
)
3641 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
3642 if (infwait_state
== infwait_normal_state
)
3644 overlay_cache_invalid
= 1;
3646 /* We have to invalidate the registers BEFORE calling
3647 target_wait because they can be loaded from the target while
3648 in target_wait. This makes remote debugging a bit more
3649 efficient for those targets that provide critical registers
3650 as part of their normal status mechanism. */
3652 registers_changed ();
3653 waiton_ptid
= pid_to_ptid (-1);
3655 /* This is the old end of the while loop. Let everybody know we
3656 want to wait for the inferior some more and get called again
3658 ecs
->wait_some_more
= 1;
3661 /* Print why the inferior has stopped. We always print something when
3662 the inferior exits, or receives a signal. The rest of the cases are
3663 dealt with later on in normal_stop() and print_it_typical(). Ideally
3664 there should be a call to this function from handle_inferior_event()
3665 each time stop_stepping() is called.*/
3667 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
3669 switch (stop_reason
)
3671 case END_STEPPING_RANGE
:
3672 /* We are done with a step/next/si/ni command. */
3673 /* For now print nothing. */
3674 /* Print a message only if not in the middle of doing a "step n"
3675 operation for n > 1 */
3676 if (!step_multi
|| !stop_step
)
3677 if (ui_out_is_mi_like_p (uiout
))
3680 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
3683 /* The inferior was terminated by a signal. */
3684 annotate_signalled ();
3685 if (ui_out_is_mi_like_p (uiout
))
3688 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
3689 ui_out_text (uiout
, "\nProgram terminated with signal ");
3690 annotate_signal_name ();
3691 ui_out_field_string (uiout
, "signal-name",
3692 target_signal_to_name (stop_info
));
3693 annotate_signal_name_end ();
3694 ui_out_text (uiout
, ", ");
3695 annotate_signal_string ();
3696 ui_out_field_string (uiout
, "signal-meaning",
3697 target_signal_to_string (stop_info
));
3698 annotate_signal_string_end ();
3699 ui_out_text (uiout
, ".\n");
3700 ui_out_text (uiout
, "The program no longer exists.\n");
3703 /* The inferior program is finished. */
3704 annotate_exited (stop_info
);
3707 if (ui_out_is_mi_like_p (uiout
))
3708 ui_out_field_string (uiout
, "reason",
3709 async_reason_lookup (EXEC_ASYNC_EXITED
));
3710 ui_out_text (uiout
, "\nProgram exited with code ");
3711 ui_out_field_fmt (uiout
, "exit-code", "0%o",
3712 (unsigned int) stop_info
);
3713 ui_out_text (uiout
, ".\n");
3717 if (ui_out_is_mi_like_p (uiout
))
3720 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
3721 ui_out_text (uiout
, "\nProgram exited normally.\n");
3723 /* Support the --return-child-result option. */
3724 return_child_result_value
= stop_info
;
3726 case SIGNAL_RECEIVED
:
3727 /* Signal received. The signal table tells us to print about
3730 ui_out_text (uiout
, "\nProgram received signal ");
3731 annotate_signal_name ();
3732 if (ui_out_is_mi_like_p (uiout
))
3734 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
3735 ui_out_field_string (uiout
, "signal-name",
3736 target_signal_to_name (stop_info
));
3737 annotate_signal_name_end ();
3738 ui_out_text (uiout
, ", ");
3739 annotate_signal_string ();
3740 ui_out_field_string (uiout
, "signal-meaning",
3741 target_signal_to_string (stop_info
));
3742 annotate_signal_string_end ();
3743 ui_out_text (uiout
, ".\n");
3746 internal_error (__FILE__
, __LINE__
,
3747 _("print_stop_reason: unrecognized enum value"));
3753 /* Here to return control to GDB when the inferior stops for real.
3754 Print appropriate messages, remove breakpoints, give terminal our modes.
3756 STOP_PRINT_FRAME nonzero means print the executing frame
3757 (pc, function, args, file, line number and line text).
3758 BREAKPOINTS_FAILED nonzero means stop was due to error
3759 attempting to insert breakpoints. */
3764 struct target_waitstatus last
;
3767 get_last_target_status (&last_ptid
, &last
);
3769 /* In non-stop mode, we don't want GDB to switch threads behind the
3770 user's back, to avoid races where the user is typing a command to
3771 apply to thread x, but GDB switches to thread y before the user
3772 finishes entering the command. */
3774 /* As with the notification of thread events, we want to delay
3775 notifying the user that we've switched thread context until
3776 the inferior actually stops.
3778 There's no point in saying anything if the inferior has exited.
3779 Note that SIGNALLED here means "exited with a signal", not
3780 "received a signal". */
3782 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
3783 && target_has_execution
3784 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3785 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3787 target_terminal_ours_for_output ();
3788 printf_filtered (_("[Switching to %s]\n"),
3789 target_pid_to_str (inferior_ptid
));
3790 annotate_thread_changed ();
3791 previous_inferior_ptid
= inferior_ptid
;
3794 /* NOTE drow/2004-01-17: Is this still necessary? */
3795 /* Make sure that the current_frame's pc is correct. This
3796 is a correction for setting up the frame info before doing
3797 gdbarch_decr_pc_after_break */
3798 if (target_has_execution
)
3799 /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
3800 gdbarch_decr_pc_after_break, the program counter can change. Ask the
3801 frame code to check for this and sort out any resultant mess.
3802 gdbarch_decr_pc_after_break needs to just go away. */
3803 deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
3805 if (!breakpoints_always_inserted_mode () && target_has_execution
)
3807 if (remove_breakpoints ())
3809 target_terminal_ours_for_output ();
3810 printf_filtered (_("\
3811 Cannot remove breakpoints because program is no longer writable.\n\
3812 It might be running in another process.\n\
3813 Further execution is probably impossible.\n"));
3817 /* If an auto-display called a function and that got a signal,
3818 delete that auto-display to avoid an infinite recursion. */
3820 if (stopped_by_random_signal
)
3821 disable_current_display ();
3823 /* Don't print a message if in the middle of doing a "step n"
3824 operation for n > 1 */
3825 if (step_multi
&& stop_step
)
3828 target_terminal_ours ();
3830 /* Set the current source location. This will also happen if we
3831 display the frame below, but the current SAL will be incorrect
3832 during a user hook-stop function. */
3833 if (target_has_stack
&& !stop_stack_dummy
)
3834 set_current_sal_from_frame (get_current_frame (), 1);
3836 /* Look up the hook_stop and run it (CLI internally handles problem
3837 of stop_command's pre-hook not existing). */
3839 catch_errors (hook_stop_stub
, stop_command
,
3840 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
3842 if (!target_has_stack
)
3848 /* Select innermost stack frame - i.e., current frame is frame 0,
3849 and current location is based on that.
3850 Don't do this on return from a stack dummy routine,
3851 or if the program has exited. */
3853 if (!stop_stack_dummy
)
3855 select_frame (get_current_frame ());
3857 /* Print current location without a level number, if
3858 we have changed functions or hit a breakpoint.
3859 Print source line if we have one.
3860 bpstat_print() contains the logic deciding in detail
3861 what to print, based on the event(s) that just occurred. */
3863 /* If --batch-silent is enabled then there's no need to print the current
3864 source location, and to try risks causing an error message about
3865 missing source files. */
3866 if (stop_print_frame
&& !batch_silent
)
3870 int do_frame_printing
= 1;
3872 bpstat_ret
= bpstat_print (stop_bpstat
);
3876 /* If we had hit a shared library event breakpoint,
3877 bpstat_print would print out this message. If we hit
3878 an OS-level shared library event, do the same
3880 if (last
.kind
== TARGET_WAITKIND_LOADED
)
3882 printf_filtered (_("Stopped due to shared library event\n"));
3883 source_flag
= SRC_LINE
; /* something bogus */
3884 do_frame_printing
= 0;
3888 /* FIXME: cagney/2002-12-01: Given that a frame ID does
3889 (or should) carry around the function and does (or
3890 should) use that when doing a frame comparison. */
3892 && frame_id_eq (step_frame_id
,
3893 get_frame_id (get_current_frame ()))
3894 && step_start_function
== find_pc_function (stop_pc
))
3895 source_flag
= SRC_LINE
; /* finished step, just print source line */
3897 source_flag
= SRC_AND_LOC
; /* print location and source line */
3899 case PRINT_SRC_AND_LOC
:
3900 source_flag
= SRC_AND_LOC
; /* print location and source line */
3902 case PRINT_SRC_ONLY
:
3903 source_flag
= SRC_LINE
;
3906 source_flag
= SRC_LINE
; /* something bogus */
3907 do_frame_printing
= 0;
3910 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
3913 if (ui_out_is_mi_like_p (uiout
))
3916 ui_out_field_int (uiout
, "thread-id",
3917 pid_to_thread_id (inferior_ptid
));
3920 struct cleanup
*back_to
= make_cleanup_ui_out_list_begin_end
3921 (uiout
, "stopped-threads");
3922 ui_out_field_int (uiout
, NULL
,
3923 pid_to_thread_id (inferior_ptid
));
3924 do_cleanups (back_to
);
3927 ui_out_field_string (uiout
, "stopped-threads", "all");
3929 /* The behavior of this routine with respect to the source
3931 SRC_LINE: Print only source line
3932 LOCATION: Print only location
3933 SRC_AND_LOC: Print location and source line */
3934 if (do_frame_printing
)
3935 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
3937 /* Display the auto-display expressions. */
3942 /* Save the function value return registers, if we care.
3943 We might be about to restore their previous contents. */
3944 if (proceed_to_finish
)
3946 /* This should not be necessary. */
3948 regcache_xfree (stop_registers
);
3950 /* NB: The copy goes through to the target picking up the value of
3951 all the registers. */
3952 stop_registers
= regcache_dup (get_current_regcache ());
3955 if (stop_stack_dummy
)
3957 /* Pop the empty frame that contains the stack dummy. POP_FRAME
3958 ends with a setting of the current frame, so we can use that
3960 frame_pop (get_current_frame ());
3961 /* Set stop_pc to what it was before we called the function.
3962 Can't rely on restore_inferior_status because that only gets
3963 called if we don't stop in the called function. */
3964 stop_pc
= read_pc ();
3965 select_frame (get_current_frame ());
3969 annotate_stopped ();
3970 if (!suppress_stop_observer
&& !step_multi
)
3971 observer_notify_normal_stop (stop_bpstat
);
3972 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3973 Delete any breakpoint that is to be deleted at the next stop. */
3974 breakpoint_auto_delete (stop_bpstat
);
3976 if (target_has_execution
3977 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3978 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3981 set_running (pid_to_ptid (-1), 0);
3983 set_running (inferior_ptid
, 0);
3988 hook_stop_stub (void *cmd
)
3990 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
3995 signal_stop_state (int signo
)
3997 /* Always stop on signals if we're just gaining control of the
3999 return signal_stop
[signo
] || stop_soon
!= NO_STOP_QUIETLY
;
4003 signal_print_state (int signo
)
4005 return signal_print
[signo
];
4009 signal_pass_state (int signo
)
4011 return signal_program
[signo
];
4015 signal_stop_update (int signo
, int state
)
4017 int ret
= signal_stop
[signo
];
4018 signal_stop
[signo
] = state
;
4023 signal_print_update (int signo
, int state
)
4025 int ret
= signal_print
[signo
];
4026 signal_print
[signo
] = state
;
4031 signal_pass_update (int signo
, int state
)
4033 int ret
= signal_program
[signo
];
4034 signal_program
[signo
] = state
;
4039 sig_print_header (void)
4041 printf_filtered (_("\
4042 Signal Stop\tPrint\tPass to program\tDescription\n"));
4046 sig_print_info (enum target_signal oursig
)
4048 char *name
= target_signal_to_name (oursig
);
4049 int name_padding
= 13 - strlen (name
);
4051 if (name_padding
<= 0)
4054 printf_filtered ("%s", name
);
4055 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
4056 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
4057 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
4058 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
4059 printf_filtered ("%s\n", target_signal_to_string (oursig
));
4062 /* Specify how various signals in the inferior should be handled. */
4065 handle_command (char *args
, int from_tty
)
4068 int digits
, wordlen
;
4069 int sigfirst
, signum
, siglast
;
4070 enum target_signal oursig
;
4073 unsigned char *sigs
;
4074 struct cleanup
*old_chain
;
4078 error_no_arg (_("signal to handle"));
4081 /* Allocate and zero an array of flags for which signals to handle. */
4083 nsigs
= (int) TARGET_SIGNAL_LAST
;
4084 sigs
= (unsigned char *) alloca (nsigs
);
4085 memset (sigs
, 0, nsigs
);
4087 /* Break the command line up into args. */
4089 argv
= buildargv (args
);
4094 old_chain
= make_cleanup_freeargv (argv
);
4096 /* Walk through the args, looking for signal oursigs, signal names, and
4097 actions. Signal numbers and signal names may be interspersed with
4098 actions, with the actions being performed for all signals cumulatively
4099 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
4101 while (*argv
!= NULL
)
4103 wordlen
= strlen (*argv
);
4104 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
4108 sigfirst
= siglast
= -1;
4110 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
4112 /* Apply action to all signals except those used by the
4113 debugger. Silently skip those. */
4116 siglast
= nsigs
- 1;
4118 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
4120 SET_SIGS (nsigs
, sigs
, signal_stop
);
4121 SET_SIGS (nsigs
, sigs
, signal_print
);
4123 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
4125 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4127 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
4129 SET_SIGS (nsigs
, sigs
, signal_print
);
4131 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
4133 SET_SIGS (nsigs
, sigs
, signal_program
);
4135 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
4137 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4139 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
4141 SET_SIGS (nsigs
, sigs
, signal_program
);
4143 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
4145 UNSET_SIGS (nsigs
, sigs
, signal_print
);
4146 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4148 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
4150 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4152 else if (digits
> 0)
4154 /* It is numeric. The numeric signal refers to our own
4155 internal signal numbering from target.h, not to host/target
4156 signal number. This is a feature; users really should be
4157 using symbolic names anyway, and the common ones like
4158 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
4160 sigfirst
= siglast
= (int)
4161 target_signal_from_command (atoi (*argv
));
4162 if ((*argv
)[digits
] == '-')
4165 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
4167 if (sigfirst
> siglast
)
4169 /* Bet he didn't figure we'd think of this case... */
4177 oursig
= target_signal_from_name (*argv
);
4178 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
4180 sigfirst
= siglast
= (int) oursig
;
4184 /* Not a number and not a recognized flag word => complain. */
4185 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
4189 /* If any signal numbers or symbol names were found, set flags for
4190 which signals to apply actions to. */
4192 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
4194 switch ((enum target_signal
) signum
)
4196 case TARGET_SIGNAL_TRAP
:
4197 case TARGET_SIGNAL_INT
:
4198 if (!allsigs
&& !sigs
[signum
])
4200 if (query ("%s is used by the debugger.\n\
4201 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal
) signum
)))
4207 printf_unfiltered (_("Not confirmed, unchanged.\n"));
4208 gdb_flush (gdb_stdout
);
4212 case TARGET_SIGNAL_0
:
4213 case TARGET_SIGNAL_DEFAULT
:
4214 case TARGET_SIGNAL_UNKNOWN
:
4215 /* Make sure that "all" doesn't print these. */
4226 target_notice_signals (inferior_ptid
);
4230 /* Show the results. */
4231 sig_print_header ();
4232 for (signum
= 0; signum
< nsigs
; signum
++)
4236 sig_print_info (signum
);
4241 do_cleanups (old_chain
);
4245 xdb_handle_command (char *args
, int from_tty
)
4248 struct cleanup
*old_chain
;
4250 /* Break the command line up into args. */
4252 argv
= buildargv (args
);
4257 old_chain
= make_cleanup_freeargv (argv
);
4258 if (argv
[1] != (char *) NULL
)
4263 bufLen
= strlen (argv
[0]) + 20;
4264 argBuf
= (char *) xmalloc (bufLen
);
4268 enum target_signal oursig
;
4270 oursig
= target_signal_from_name (argv
[0]);
4271 memset (argBuf
, 0, bufLen
);
4272 if (strcmp (argv
[1], "Q") == 0)
4273 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4276 if (strcmp (argv
[1], "s") == 0)
4278 if (!signal_stop
[oursig
])
4279 sprintf (argBuf
, "%s %s", argv
[0], "stop");
4281 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
4283 else if (strcmp (argv
[1], "i") == 0)
4285 if (!signal_program
[oursig
])
4286 sprintf (argBuf
, "%s %s", argv
[0], "pass");
4288 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
4290 else if (strcmp (argv
[1], "r") == 0)
4292 if (!signal_print
[oursig
])
4293 sprintf (argBuf
, "%s %s", argv
[0], "print");
4295 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4301 handle_command (argBuf
, from_tty
);
4303 printf_filtered (_("Invalid signal handling flag.\n"));
4308 do_cleanups (old_chain
);
4311 /* Print current contents of the tables set by the handle command.
4312 It is possible we should just be printing signals actually used
4313 by the current target (but for things to work right when switching
4314 targets, all signals should be in the signal tables). */
4317 signals_info (char *signum_exp
, int from_tty
)
4319 enum target_signal oursig
;
4320 sig_print_header ();
4324 /* First see if this is a symbol name. */
4325 oursig
= target_signal_from_name (signum_exp
);
4326 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
4328 /* No, try numeric. */
4330 target_signal_from_command (parse_and_eval_long (signum_exp
));
4332 sig_print_info (oursig
);
4336 printf_filtered ("\n");
4337 /* These ugly casts brought to you by the native VAX compiler. */
4338 for (oursig
= TARGET_SIGNAL_FIRST
;
4339 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
4340 oursig
= (enum target_signal
) ((int) oursig
+ 1))
4344 if (oursig
!= TARGET_SIGNAL_UNKNOWN
4345 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
4346 sig_print_info (oursig
);
4349 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
4352 struct inferior_status
4354 enum target_signal stop_signal
;
4358 int stop_stack_dummy
;
4359 int stopped_by_random_signal
;
4360 int stepping_over_breakpoint
;
4361 CORE_ADDR step_range_start
;
4362 CORE_ADDR step_range_end
;
4363 struct frame_id step_frame_id
;
4364 enum step_over_calls_kind step_over_calls
;
4365 CORE_ADDR step_resume_break_address
;
4366 int stop_after_trap
;
4369 /* These are here because if call_function_by_hand has written some
4370 registers and then decides to call error(), we better not have changed
4372 struct regcache
*registers
;
4374 /* A frame unique identifier. */
4375 struct frame_id selected_frame_id
;
4377 int breakpoint_proceeded
;
4378 int restore_stack_info
;
4379 int proceed_to_finish
;
4383 write_inferior_status_register (struct inferior_status
*inf_status
, int regno
,
4386 int size
= register_size (current_gdbarch
, regno
);
4387 void *buf
= alloca (size
);
4388 store_signed_integer (buf
, size
, val
);
4389 regcache_raw_write (inf_status
->registers
, regno
, buf
);
4392 /* Save all of the information associated with the inferior<==>gdb
4393 connection. INF_STATUS is a pointer to a "struct inferior_status"
4394 (defined in inferior.h). */
4396 struct inferior_status
*
4397 save_inferior_status (int restore_stack_info
)
4399 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
4401 inf_status
->stop_signal
= stop_signal
;
4402 inf_status
->stop_pc
= stop_pc
;
4403 inf_status
->stop_step
= stop_step
;
4404 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
4405 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
4406 inf_status
->stepping_over_breakpoint
= stepping_over_breakpoint
;
4407 inf_status
->step_range_start
= step_range_start
;
4408 inf_status
->step_range_end
= step_range_end
;
4409 inf_status
->step_frame_id
= step_frame_id
;
4410 inf_status
->step_over_calls
= step_over_calls
;
4411 inf_status
->stop_after_trap
= stop_after_trap
;
4412 inf_status
->stop_soon
= stop_soon
;
4413 /* Save original bpstat chain here; replace it with copy of chain.
4414 If caller's caller is walking the chain, they'll be happier if we
4415 hand them back the original chain when restore_inferior_status is
4417 inf_status
->stop_bpstat
= stop_bpstat
;
4418 stop_bpstat
= bpstat_copy (stop_bpstat
);
4419 inf_status
->breakpoint_proceeded
= breakpoint_proceeded
;
4420 inf_status
->restore_stack_info
= restore_stack_info
;
4421 inf_status
->proceed_to_finish
= proceed_to_finish
;
4423 inf_status
->registers
= regcache_dup (get_current_regcache ());
4425 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
4430 restore_selected_frame (void *args
)
4432 struct frame_id
*fid
= (struct frame_id
*) args
;
4433 struct frame_info
*frame
;
4435 frame
= frame_find_by_id (*fid
);
4437 /* If inf_status->selected_frame_id is NULL, there was no previously
4441 warning (_("Unable to restore previously selected frame."));
4445 select_frame (frame
);
4451 restore_inferior_status (struct inferior_status
*inf_status
)
4453 stop_signal
= inf_status
->stop_signal
;
4454 stop_pc
= inf_status
->stop_pc
;
4455 stop_step
= inf_status
->stop_step
;
4456 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
4457 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
4458 stepping_over_breakpoint
= inf_status
->stepping_over_breakpoint
;
4459 step_range_start
= inf_status
->step_range_start
;
4460 step_range_end
= inf_status
->step_range_end
;
4461 step_frame_id
= inf_status
->step_frame_id
;
4462 step_over_calls
= inf_status
->step_over_calls
;
4463 stop_after_trap
= inf_status
->stop_after_trap
;
4464 stop_soon
= inf_status
->stop_soon
;
4465 bpstat_clear (&stop_bpstat
);
4466 stop_bpstat
= inf_status
->stop_bpstat
;
4467 breakpoint_proceeded
= inf_status
->breakpoint_proceeded
;
4468 proceed_to_finish
= inf_status
->proceed_to_finish
;
4470 /* The inferior can be gone if the user types "print exit(0)"
4471 (and perhaps other times). */
4472 if (target_has_execution
)
4473 /* NB: The register write goes through to the target. */
4474 regcache_cpy (get_current_regcache (), inf_status
->registers
);
4475 regcache_xfree (inf_status
->registers
);
4477 /* FIXME: If we are being called after stopping in a function which
4478 is called from gdb, we should not be trying to restore the
4479 selected frame; it just prints a spurious error message (The
4480 message is useful, however, in detecting bugs in gdb (like if gdb
4481 clobbers the stack)). In fact, should we be restoring the
4482 inferior status at all in that case? . */
4484 if (target_has_stack
&& inf_status
->restore_stack_info
)
4486 /* The point of catch_errors is that if the stack is clobbered,
4487 walking the stack might encounter a garbage pointer and
4488 error() trying to dereference it. */
4490 (restore_selected_frame
, &inf_status
->selected_frame_id
,
4491 "Unable to restore previously selected frame:\n",
4492 RETURN_MASK_ERROR
) == 0)
4493 /* Error in restoring the selected frame. Select the innermost
4495 select_frame (get_current_frame ());
4503 do_restore_inferior_status_cleanup (void *sts
)
4505 restore_inferior_status (sts
);
4509 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
4511 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
4515 discard_inferior_status (struct inferior_status
*inf_status
)
4517 /* See save_inferior_status for info on stop_bpstat. */
4518 bpstat_clear (&inf_status
->stop_bpstat
);
4519 regcache_xfree (inf_status
->registers
);
4524 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
4526 struct target_waitstatus last
;
4529 get_last_target_status (&last_ptid
, &last
);
4531 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
4534 if (!ptid_equal (last_ptid
, pid
))
4537 *child_pid
= last
.value
.related_pid
;
4542 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
4544 struct target_waitstatus last
;
4547 get_last_target_status (&last_ptid
, &last
);
4549 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
4552 if (!ptid_equal (last_ptid
, pid
))
4555 *child_pid
= last
.value
.related_pid
;
4560 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
4562 struct target_waitstatus last
;
4565 get_last_target_status (&last_ptid
, &last
);
4567 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
4570 if (!ptid_equal (last_ptid
, pid
))
4573 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
4577 /* Oft used ptids */
4579 ptid_t minus_one_ptid
;
4581 /* Create a ptid given the necessary PID, LWP, and TID components. */
4584 ptid_build (int pid
, long lwp
, long tid
)
4594 /* Create a ptid from just a pid. */
4597 pid_to_ptid (int pid
)
4599 return ptid_build (pid
, 0, 0);
4602 /* Fetch the pid (process id) component from a ptid. */
4605 ptid_get_pid (ptid_t ptid
)
4610 /* Fetch the lwp (lightweight process) component from a ptid. */
4613 ptid_get_lwp (ptid_t ptid
)
4618 /* Fetch the tid (thread id) component from a ptid. */
4621 ptid_get_tid (ptid_t ptid
)
4626 /* ptid_equal() is used to test equality of two ptids. */
4629 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
4631 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
4632 && ptid1
.tid
== ptid2
.tid
);
4635 /* restore_inferior_ptid() will be used by the cleanup machinery
4636 to restore the inferior_ptid value saved in a call to
4637 save_inferior_ptid(). */
4640 restore_inferior_ptid (void *arg
)
4642 ptid_t
*saved_ptid_ptr
= arg
;
4643 inferior_ptid
= *saved_ptid_ptr
;
4647 /* Save the value of inferior_ptid so that it may be restored by a
4648 later call to do_cleanups(). Returns the struct cleanup pointer
4649 needed for later doing the cleanup. */
4652 save_inferior_ptid (void)
4654 ptid_t
*saved_ptid_ptr
;
4656 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
4657 *saved_ptid_ptr
= inferior_ptid
;
4658 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
4663 static int non_stop_1
= 0;
4666 set_non_stop (char *args
, int from_tty
,
4667 struct cmd_list_element
*c
)
4669 if (target_has_execution
)
4671 non_stop_1
= non_stop
;
4672 error (_("Cannot change this setting while the inferior is running."));
4675 non_stop
= non_stop_1
;
4679 show_non_stop (struct ui_file
*file
, int from_tty
,
4680 struct cmd_list_element
*c
, const char *value
)
4682 fprintf_filtered (file
,
4683 _("Controlling the inferior in non-stop mode is %s.\n"),
4689 _initialize_infrun (void)
4693 struct cmd_list_element
*c
;
4695 add_info ("signals", signals_info
, _("\
4696 What debugger does when program gets various signals.\n\
4697 Specify a signal as argument to print info on that signal only."));
4698 add_info_alias ("handle", "signals", 0);
4700 add_com ("handle", class_run
, handle_command
, _("\
4701 Specify how to handle a signal.\n\
4702 Args are signals and actions to apply to those signals.\n\
4703 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4704 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4705 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4706 The special arg \"all\" is recognized to mean all signals except those\n\
4707 used by the debugger, typically SIGTRAP and SIGINT.\n\
4708 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4709 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4710 Stop means reenter debugger if this signal happens (implies print).\n\
4711 Print means print a message if this signal happens.\n\
4712 Pass means let program see this signal; otherwise program doesn't know.\n\
4713 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4714 Pass and Stop may be combined."));
4717 add_com ("lz", class_info
, signals_info
, _("\
4718 What debugger does when program gets various signals.\n\
4719 Specify a signal as argument to print info on that signal only."));
4720 add_com ("z", class_run
, xdb_handle_command
, _("\
4721 Specify how to handle a signal.\n\
4722 Args are signals and actions to apply to those signals.\n\
4723 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4724 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4725 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4726 The special arg \"all\" is recognized to mean all signals except those\n\
4727 used by the debugger, typically SIGTRAP and SIGINT.\n\
4728 Recognized actions include \"s\" (toggles between stop and nostop), \n\
4729 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4730 nopass), \"Q\" (noprint)\n\
4731 Stop means reenter debugger if this signal happens (implies print).\n\
4732 Print means print a message if this signal happens.\n\
4733 Pass means let program see this signal; otherwise program doesn't know.\n\
4734 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4735 Pass and Stop may be combined."));
4739 stop_command
= add_cmd ("stop", class_obscure
,
4740 not_just_help_class_command
, _("\
4741 There is no `stop' command, but you can set a hook on `stop'.\n\
4742 This allows you to set a list of commands to be run each time execution\n\
4743 of the program stops."), &cmdlist
);
4745 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
4746 Set inferior debugging."), _("\
4747 Show inferior debugging."), _("\
4748 When non-zero, inferior specific debugging is enabled."),
4751 &setdebuglist
, &showdebuglist
);
4753 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
4754 Set displaced stepping debugging."), _("\
4755 Show displaced stepping debugging."), _("\
4756 When non-zero, displaced stepping specific debugging is enabled."),
4758 show_debug_displaced
,
4759 &setdebuglist
, &showdebuglist
);
4761 add_setshow_boolean_cmd ("non-stop", no_class
,
4763 Set whether gdb controls the inferior in non-stop mode."), _("\
4764 Show whether gdb controls the inferior in non-stop mode."), _("\
4765 When debugging a multi-threaded program and this setting is\n\
4766 off (the default, also called all-stop mode), when one thread stops\n\
4767 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
4768 all other threads in the program while you interact with the thread of\n\
4769 interest. When you continue or step a thread, you can allow the other\n\
4770 threads to run, or have them remain stopped, but while you inspect any\n\
4771 thread's state, all threads stop.\n\
4773 In non-stop mode, when one thread stops, other threads can continue\n\
4774 to run freely. You'll be able to step each thread independently,\n\
4775 leave it stopped or free to run as needed."),
4781 numsigs
= (int) TARGET_SIGNAL_LAST
;
4782 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
4783 signal_print
= (unsigned char *)
4784 xmalloc (sizeof (signal_print
[0]) * numsigs
);
4785 signal_program
= (unsigned char *)
4786 xmalloc (sizeof (signal_program
[0]) * numsigs
);
4787 for (i
= 0; i
< numsigs
; i
++)
4790 signal_print
[i
] = 1;
4791 signal_program
[i
] = 1;
4794 /* Signals caused by debugger's own actions
4795 should not be given to the program afterwards. */
4796 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
4797 signal_program
[TARGET_SIGNAL_INT
] = 0;
4799 /* Signals that are not errors should not normally enter the debugger. */
4800 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
4801 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
4802 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
4803 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
4804 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
4805 signal_print
[TARGET_SIGNAL_PROF
] = 0;
4806 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
4807 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
4808 signal_stop
[TARGET_SIGNAL_IO
] = 0;
4809 signal_print
[TARGET_SIGNAL_IO
] = 0;
4810 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
4811 signal_print
[TARGET_SIGNAL_POLL
] = 0;
4812 signal_stop
[TARGET_SIGNAL_URG
] = 0;
4813 signal_print
[TARGET_SIGNAL_URG
] = 0;
4814 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
4815 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
4817 /* These signals are used internally by user-level thread
4818 implementations. (See signal(5) on Solaris.) Like the above
4819 signals, a healthy program receives and handles them as part of
4820 its normal operation. */
4821 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
4822 signal_print
[TARGET_SIGNAL_LWP
] = 0;
4823 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
4824 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
4825 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
4826 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
4828 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
4829 &stop_on_solib_events
, _("\
4830 Set stopping for shared library events."), _("\
4831 Show stopping for shared library events."), _("\
4832 If nonzero, gdb will give control to the user when the dynamic linker\n\
4833 notifies gdb of shared library events. The most common event of interest\n\
4834 to the user would be loading/unloading of a new library."),
4836 show_stop_on_solib_events
,
4837 &setlist
, &showlist
);
4839 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
4840 follow_fork_mode_kind_names
,
4841 &follow_fork_mode_string
, _("\
4842 Set debugger response to a program call of fork or vfork."), _("\
4843 Show debugger response to a program call of fork or vfork."), _("\
4844 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4845 parent - the original process is debugged after a fork\n\
4846 child - the new process is debugged after a fork\n\
4847 The unfollowed process will continue to run.\n\
4848 By default, the debugger will follow the parent process."),
4850 show_follow_fork_mode_string
,
4851 &setlist
, &showlist
);
4853 add_setshow_enum_cmd ("scheduler-locking", class_run
,
4854 scheduler_enums
, &scheduler_mode
, _("\
4855 Set mode for locking scheduler during execution."), _("\
4856 Show mode for locking scheduler during execution."), _("\
4857 off == no locking (threads may preempt at any time)\n\
4858 on == full locking (no thread except the current thread may run)\n\
4859 step == scheduler locked during every single-step operation.\n\
4860 In this mode, no other thread may run during a step command.\n\
4861 Other threads may run while stepping over a function call ('next')."),
4862 set_schedlock_func
, /* traps on target vector */
4863 show_scheduler_mode
,
4864 &setlist
, &showlist
);
4866 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
4867 Set mode of the step operation."), _("\
4868 Show mode of the step operation."), _("\
4869 When set, doing a step over a function without debug line information\n\
4870 will stop at the first instruction of that function. Otherwise, the\n\
4871 function is skipped and the step command stops at a different source line."),
4873 show_step_stop_if_no_debug
,
4874 &setlist
, &showlist
);
4876 add_setshow_boolean_cmd ("can-use-displaced-stepping", class_maintenance
,
4877 &can_use_displaced_stepping
, _("\
4878 Set debugger's willingness to use displaced stepping."), _("\
4879 Show debugger's willingness to use displaced stepping."), _("\
4880 If zero, gdb will not use displaced stepping to step over\n\
4881 breakpoints, even if such is supported by the target."),
4883 show_can_use_displaced_stepping
,
4884 &maintenance_set_cmdlist
,
4885 &maintenance_show_cmdlist
);
4887 /* ptid initializations */
4888 null_ptid
= ptid_build (0, 0, 0);
4889 minus_one_ptid
= ptid_build (-1, 0, 0);
4890 inferior_ptid
= null_ptid
;
4891 target_last_wait_ptid
= minus_one_ptid
;
4892 displaced_step_ptid
= null_ptid
;
4894 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);