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 static int currently_stepping (struct thread_info
*tp
);
78 static void xdb_handle_command (char *args
, int from_tty
);
80 static int prepare_to_proceed (int);
82 void _initialize_infrun (void);
84 /* When set, stop the 'step' command if we enter a function which has
85 no line number information. The normal behavior is that we step
86 over such function. */
87 int step_stop_if_no_debug
= 0;
89 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
90 struct cmd_list_element
*c
, const char *value
)
92 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
95 /* In asynchronous mode, but simulating synchronous execution. */
97 int sync_execution
= 0;
99 /* wait_for_inferior and normal_stop use this to notify the user
100 when the inferior stopped in a different thread than it had been
103 static ptid_t previous_inferior_ptid
;
105 int debug_displaced
= 0;
107 show_debug_displaced (struct ui_file
*file
, int from_tty
,
108 struct cmd_list_element
*c
, const char *value
)
110 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
113 static int debug_infrun
= 0;
115 show_debug_infrun (struct ui_file
*file
, int from_tty
,
116 struct cmd_list_element
*c
, const char *value
)
118 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
121 /* If the program uses ELF-style shared libraries, then calls to
122 functions in shared libraries go through stubs, which live in a
123 table called the PLT (Procedure Linkage Table). The first time the
124 function is called, the stub sends control to the dynamic linker,
125 which looks up the function's real address, patches the stub so
126 that future calls will go directly to the function, and then passes
127 control to the function.
129 If we are stepping at the source level, we don't want to see any of
130 this --- we just want to skip over the stub and the dynamic linker.
131 The simple approach is to single-step until control leaves the
134 However, on some systems (e.g., Red Hat's 5.2 distribution) the
135 dynamic linker calls functions in the shared C library, so you
136 can't tell from the PC alone whether the dynamic linker is still
137 running. In this case, we use a step-resume breakpoint to get us
138 past the dynamic linker, as if we were using "next" to step over a
141 in_solib_dynsym_resolve_code() says whether we're in the dynamic
142 linker code or not. Normally, this means we single-step. However,
143 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
144 address where we can place a step-resume breakpoint to get past the
145 linker's symbol resolution function.
147 in_solib_dynsym_resolve_code() can generally be implemented in a
148 pretty portable way, by comparing the PC against the address ranges
149 of the dynamic linker's sections.
151 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
152 it depends on internal details of the dynamic linker. It's usually
153 not too hard to figure out where to put a breakpoint, but it
154 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
155 sanity checking. If it can't figure things out, returning zero and
156 getting the (possibly confusing) stepping behavior is better than
157 signalling an error, which will obscure the change in the
160 /* This function returns TRUE if pc is the address of an instruction
161 that lies within the dynamic linker (such as the event hook, or the
164 This function must be used only when a dynamic linker event has
165 been caught, and the inferior is being stepped out of the hook, or
166 undefined results are guaranteed. */
168 #ifndef SOLIB_IN_DYNAMIC_LINKER
169 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
173 /* Convert the #defines into values. This is temporary until wfi control
174 flow is completely sorted out. */
176 #ifndef CANNOT_STEP_HW_WATCHPOINTS
177 #define CANNOT_STEP_HW_WATCHPOINTS 0
179 #undef CANNOT_STEP_HW_WATCHPOINTS
180 #define CANNOT_STEP_HW_WATCHPOINTS 1
183 /* Tables of how to react to signals; the user sets them. */
185 static unsigned char *signal_stop
;
186 static unsigned char *signal_print
;
187 static unsigned char *signal_program
;
189 #define SET_SIGS(nsigs,sigs,flags) \
191 int signum = (nsigs); \
192 while (signum-- > 0) \
193 if ((sigs)[signum]) \
194 (flags)[signum] = 1; \
197 #define UNSET_SIGS(nsigs,sigs,flags) \
199 int signum = (nsigs); \
200 while (signum-- > 0) \
201 if ((sigs)[signum]) \
202 (flags)[signum] = 0; \
205 /* Value to pass to target_resume() to cause all threads to resume */
207 #define RESUME_ALL (pid_to_ptid (-1))
209 /* Command list pointer for the "stop" placeholder. */
211 static struct cmd_list_element
*stop_command
;
213 /* Function inferior was in as of last step command. */
215 static struct symbol
*step_start_function
;
217 /* Nonzero if we want to give control to the user when we're notified
218 of shared library events by the dynamic linker. */
219 static int stop_on_solib_events
;
221 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
222 struct cmd_list_element
*c
, const char *value
)
224 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
228 /* Nonzero means expecting a trace trap
229 and should stop the inferior and return silently when it happens. */
233 /* Nonzero means expecting a trap and caller will handle it themselves.
234 It is used after attach, due to attaching to a process;
235 when running in the shell before the child program has been exec'd;
236 and when running some kinds of remote stuff (FIXME?). */
238 enum stop_kind stop_soon
;
240 /* Nonzero if proceed is being used for a "finish" command or a similar
241 situation when stop_registers should be saved. */
243 int proceed_to_finish
;
245 /* Save register contents here when about to pop a stack dummy frame,
246 if-and-only-if proceed_to_finish is set.
247 Thus this contains the return value from the called function (assuming
248 values are returned in a register). */
250 struct regcache
*stop_registers
;
252 /* Nonzero after stop if current stack frame should be printed. */
254 static int stop_print_frame
;
256 /* This is a cached copy of the pid/waitstatus of the last event
257 returned by target_wait()/deprecated_target_wait_hook(). This
258 information is returned by get_last_target_status(). */
259 static ptid_t target_last_wait_ptid
;
260 static struct target_waitstatus target_last_waitstatus
;
262 static void context_switch (ptid_t ptid
);
264 void init_thread_stepping_state (struct thread_info
*tss
);
266 void init_infwait_state (void);
268 /* This is used to remember when a fork, vfork or exec event
269 was caught by a catchpoint, and thus the event is to be
270 followed at the next resume of the inferior, and not
274 enum target_waitkind kind
;
281 char *execd_pathname
;
285 static const char follow_fork_mode_child
[] = "child";
286 static const char follow_fork_mode_parent
[] = "parent";
288 static const char *follow_fork_mode_kind_names
[] = {
289 follow_fork_mode_child
,
290 follow_fork_mode_parent
,
294 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
296 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
297 struct cmd_list_element
*c
, const char *value
)
299 fprintf_filtered (file
, _("\
300 Debugger response to a program call of fork or vfork is \"%s\".\n"),
308 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
310 return target_follow_fork (follow_child
);
314 follow_inferior_reset_breakpoints (void)
316 struct thread_info
*tp
= inferior_thread ();
318 /* Was there a step_resume breakpoint? (There was if the user
319 did a "next" at the fork() call.) If so, explicitly reset its
322 step_resumes are a form of bp that are made to be per-thread.
323 Since we created the step_resume bp when the parent process
324 was being debugged, and now are switching to the child process,
325 from the breakpoint package's viewpoint, that's a switch of
326 "threads". We must update the bp's notion of which thread
327 it is for, or it'll be ignored when it triggers. */
329 if (tp
->step_resume_breakpoint
)
330 breakpoint_re_set_thread (tp
->step_resume_breakpoint
);
332 /* Reinsert all breakpoints in the child. The user may have set
333 breakpoints after catching the fork, in which case those
334 were never set in the child, but only in the parent. This makes
335 sure the inserted breakpoints match the breakpoint list. */
337 breakpoint_re_set ();
338 insert_breakpoints ();
341 /* EXECD_PATHNAME is assumed to be non-NULL. */
344 follow_exec (ptid_t pid
, char *execd_pathname
)
346 ptid_t saved_pid
= pid
;
347 struct target_ops
*tgt
;
348 struct thread_info
*th
= inferior_thread ();
350 /* This is an exec event that we actually wish to pay attention to.
351 Refresh our symbol table to the newly exec'd program, remove any
354 If there are breakpoints, they aren't really inserted now,
355 since the exec() transformed our inferior into a fresh set
358 We want to preserve symbolic breakpoints on the list, since
359 we have hopes that they can be reset after the new a.out's
360 symbol table is read.
362 However, any "raw" breakpoints must be removed from the list
363 (e.g., the solib bp's), since their address is probably invalid
366 And, we DON'T want to call delete_breakpoints() here, since
367 that may write the bp's "shadow contents" (the instruction
368 value that was overwritten witha TRAP instruction). Since
369 we now have a new a.out, those shadow contents aren't valid. */
370 update_breakpoints_after_exec ();
372 /* If there was one, it's gone now. We cannot truly step-to-next
373 statement through an exec(). */
374 th
->step_resume_breakpoint
= NULL
;
375 th
->step_range_start
= 0;
376 th
->step_range_end
= 0;
378 /* What is this a.out's name? */
379 printf_unfiltered (_("Executing new program: %s\n"), execd_pathname
);
381 /* We've followed the inferior through an exec. Therefore, the
382 inferior has essentially been killed & reborn. */
384 gdb_flush (gdb_stdout
);
385 generic_mourn_inferior ();
386 /* Because mourn_inferior resets inferior_ptid. */
387 inferior_ptid
= saved_pid
;
389 if (gdb_sysroot
&& *gdb_sysroot
)
391 char *name
= alloca (strlen (gdb_sysroot
)
392 + strlen (execd_pathname
)
394 strcpy (name
, gdb_sysroot
);
395 strcat (name
, execd_pathname
);
396 execd_pathname
= name
;
399 /* That a.out is now the one to use. */
400 exec_file_attach (execd_pathname
, 0);
402 /* Reset the shared library package. This ensures that we get a
403 shlib event when the child reaches "_start", at which point the
404 dld will have had a chance to initialize the child. */
405 /* Also, loading a symbol file below may trigger symbol lookups, and
406 we don't want those to be satisfied by the libraries of the
407 previous incarnation of this process. */
408 no_shared_libraries (NULL
, 0);
410 /* Load the main file's symbols. */
411 symbol_file_add_main (execd_pathname
, 0);
413 #ifdef SOLIB_CREATE_INFERIOR_HOOK
414 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
416 solib_create_inferior_hook ();
419 /* Reinsert all breakpoints. (Those which were symbolic have
420 been reset to the proper address in the new a.out, thanks
421 to symbol_file_command...) */
422 insert_breakpoints ();
424 /* The next resume of this inferior should bring it to the shlib
425 startup breakpoints. (If the user had also set bp's on
426 "main" from the old (parent) process, then they'll auto-
427 matically get reset there in the new process.) */
430 /* Non-zero if we just simulating a single-step. This is needed
431 because we cannot remove the breakpoints in the inferior process
432 until after the `wait' in `wait_for_inferior'. */
433 static int singlestep_breakpoints_inserted_p
= 0;
435 /* The thread we inserted single-step breakpoints for. */
436 static ptid_t singlestep_ptid
;
438 /* PC when we started this single-step. */
439 static CORE_ADDR singlestep_pc
;
441 /* If another thread hit the singlestep breakpoint, we save the original
442 thread here so that we can resume single-stepping it later. */
443 static ptid_t saved_singlestep_ptid
;
444 static int stepping_past_singlestep_breakpoint
;
446 /* If not equal to null_ptid, this means that after stepping over breakpoint
447 is finished, we need to switch to deferred_step_ptid, and step it.
449 The use case is when one thread has hit a breakpoint, and then the user
450 has switched to another thread and issued 'step'. We need to step over
451 breakpoint in the thread which hit the breakpoint, but then continue
452 stepping the thread user has selected. */
453 static ptid_t deferred_step_ptid
;
455 /* Displaced stepping. */
457 /* In non-stop debugging mode, we must take special care to manage
458 breakpoints properly; in particular, the traditional strategy for
459 stepping a thread past a breakpoint it has hit is unsuitable.
460 'Displaced stepping' is a tactic for stepping one thread past a
461 breakpoint it has hit while ensuring that other threads running
462 concurrently will hit the breakpoint as they should.
464 The traditional way to step a thread T off a breakpoint in a
465 multi-threaded program in all-stop mode is as follows:
467 a0) Initially, all threads are stopped, and breakpoints are not
469 a1) We single-step T, leaving breakpoints uninserted.
470 a2) We insert breakpoints, and resume all threads.
472 In non-stop debugging, however, this strategy is unsuitable: we
473 don't want to have to stop all threads in the system in order to
474 continue or step T past a breakpoint. Instead, we use displaced
477 n0) Initially, T is stopped, other threads are running, and
478 breakpoints are inserted.
479 n1) We copy the instruction "under" the breakpoint to a separate
480 location, outside the main code stream, making any adjustments
481 to the instruction, register, and memory state as directed by
483 n2) We single-step T over the instruction at its new location.
484 n3) We adjust the resulting register and memory state as directed
485 by T's architecture. This includes resetting T's PC to point
486 back into the main instruction stream.
489 This approach depends on the following gdbarch methods:
491 - gdbarch_max_insn_length and gdbarch_displaced_step_location
492 indicate where to copy the instruction, and how much space must
493 be reserved there. We use these in step n1.
495 - gdbarch_displaced_step_copy_insn copies a instruction to a new
496 address, and makes any necessary adjustments to the instruction,
497 register contents, and memory. We use this in step n1.
499 - gdbarch_displaced_step_fixup adjusts registers and memory after
500 we have successfuly single-stepped the instruction, to yield the
501 same effect the instruction would have had if we had executed it
502 at its original address. We use this in step n3.
504 - gdbarch_displaced_step_free_closure provides cleanup.
506 The gdbarch_displaced_step_copy_insn and
507 gdbarch_displaced_step_fixup functions must be written so that
508 copying an instruction with gdbarch_displaced_step_copy_insn,
509 single-stepping across the copied instruction, and then applying
510 gdbarch_displaced_insn_fixup should have the same effects on the
511 thread's memory and registers as stepping the instruction in place
512 would have. Exactly which responsibilities fall to the copy and
513 which fall to the fixup is up to the author of those functions.
515 See the comments in gdbarch.sh for details.
517 Note that displaced stepping and software single-step cannot
518 currently be used in combination, although with some care I think
519 they could be made to. Software single-step works by placing
520 breakpoints on all possible subsequent instructions; if the
521 displaced instruction is a PC-relative jump, those breakpoints
522 could fall in very strange places --- on pages that aren't
523 executable, or at addresses that are not proper instruction
524 boundaries. (We do generally let other threads run while we wait
525 to hit the software single-step breakpoint, and they might
526 encounter such a corrupted instruction.) One way to work around
527 this would be to have gdbarch_displaced_step_copy_insn fully
528 simulate the effect of PC-relative instructions (and return NULL)
529 on architectures that use software single-stepping.
531 In non-stop mode, we can have independent and simultaneous step
532 requests, so more than one thread may need to simultaneously step
533 over a breakpoint. The current implementation assumes there is
534 only one scratch space per process. In this case, we have to
535 serialize access to the scratch space. If thread A wants to step
536 over a breakpoint, but we are currently waiting for some other
537 thread to complete a displaced step, we leave thread A stopped and
538 place it in the displaced_step_request_queue. Whenever a displaced
539 step finishes, we pick the next thread in the queue and start a new
540 displaced step operation on it. See displaced_step_prepare and
541 displaced_step_fixup for details. */
543 /* If this is not null_ptid, this is the thread carrying out a
544 displaced single-step. This thread's state will require fixing up
545 once it has completed its step. */
546 static ptid_t displaced_step_ptid
;
548 struct displaced_step_request
551 struct displaced_step_request
*next
;
554 /* A queue of pending displaced stepping requests. */
555 struct displaced_step_request
*displaced_step_request_queue
;
557 /* The architecture the thread had when we stepped it. */
558 static struct gdbarch
*displaced_step_gdbarch
;
560 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
561 for post-step cleanup. */
562 static struct displaced_step_closure
*displaced_step_closure
;
564 /* The address of the original instruction, and the copy we made. */
565 static CORE_ADDR displaced_step_original
, displaced_step_copy
;
567 /* Saved contents of copy area. */
568 static gdb_byte
*displaced_step_saved_copy
;
570 /* When this is non-zero, we are allowed to use displaced stepping, if
571 the architecture supports it. When this is zero, we use
572 traditional the hold-and-step approach. */
573 int can_use_displaced_stepping
= 1;
575 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
576 struct cmd_list_element
*c
,
579 fprintf_filtered (file
, _("\
580 Debugger's willingness to use displaced stepping to step over "
581 "breakpoints is %s.\n"), value
);
584 /* Return non-zero if displaced stepping is enabled, and can be used
587 use_displaced_stepping (struct gdbarch
*gdbarch
)
589 return (can_use_displaced_stepping
590 && gdbarch_displaced_step_copy_insn_p (gdbarch
));
593 /* Clean out any stray displaced stepping state. */
595 displaced_step_clear (void)
597 /* Indicate that there is no cleanup pending. */
598 displaced_step_ptid
= null_ptid
;
600 if (displaced_step_closure
)
602 gdbarch_displaced_step_free_closure (displaced_step_gdbarch
,
603 displaced_step_closure
);
604 displaced_step_closure
= NULL
;
609 cleanup_displaced_step_closure (void *ptr
)
611 struct displaced_step_closure
*closure
= ptr
;
613 gdbarch_displaced_step_free_closure (current_gdbarch
, closure
);
616 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
618 displaced_step_dump_bytes (struct ui_file
*file
,
624 for (i
= 0; i
< len
; i
++)
625 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
626 fputs_unfiltered ("\n", file
);
629 /* Prepare to single-step, using displaced stepping.
631 Note that we cannot use displaced stepping when we have a signal to
632 deliver. If we have a signal to deliver and an instruction to step
633 over, then after the step, there will be no indication from the
634 target whether the thread entered a signal handler or ignored the
635 signal and stepped over the instruction successfully --- both cases
636 result in a simple SIGTRAP. In the first case we mustn't do a
637 fixup, and in the second case we must --- but we can't tell which.
638 Comments in the code for 'random signals' in handle_inferior_event
639 explain how we handle this case instead.
641 Returns 1 if preparing was successful -- this thread is going to be
642 stepped now; or 0 if displaced stepping this thread got queued. */
644 displaced_step_prepare (ptid_t ptid
)
646 struct cleanup
*old_cleanups
;
647 struct regcache
*regcache
= get_thread_regcache (ptid
);
648 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
649 CORE_ADDR original
, copy
;
651 struct displaced_step_closure
*closure
;
653 /* We should never reach this function if the architecture does not
654 support displaced stepping. */
655 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
657 /* For the first cut, we're displaced stepping one thread at a
660 if (!ptid_equal (displaced_step_ptid
, null_ptid
))
662 /* Already waiting for a displaced step to finish. Defer this
663 request and place in queue. */
664 struct displaced_step_request
*req
, *new_req
;
667 fprintf_unfiltered (gdb_stdlog
,
668 "displaced: defering step of %s\n",
669 target_pid_to_str (ptid
));
671 new_req
= xmalloc (sizeof (*new_req
));
672 new_req
->ptid
= ptid
;
673 new_req
->next
= NULL
;
675 if (displaced_step_request_queue
)
677 for (req
= displaced_step_request_queue
;
684 displaced_step_request_queue
= new_req
;
691 fprintf_unfiltered (gdb_stdlog
,
692 "displaced: stepping %s now\n",
693 target_pid_to_str (ptid
));
696 displaced_step_clear ();
698 original
= regcache_read_pc (regcache
);
700 copy
= gdbarch_displaced_step_location (gdbarch
);
701 len
= gdbarch_max_insn_length (gdbarch
);
703 /* Save the original contents of the copy area. */
704 displaced_step_saved_copy
= xmalloc (len
);
705 old_cleanups
= make_cleanup (free_current_contents
,
706 &displaced_step_saved_copy
);
707 read_memory (copy
, displaced_step_saved_copy
, len
);
710 fprintf_unfiltered (gdb_stdlog
, "displaced: saved 0x%s: ",
712 displaced_step_dump_bytes (gdb_stdlog
, displaced_step_saved_copy
, len
);
715 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
716 original
, copy
, regcache
);
718 /* We don't support the fully-simulated case at present. */
719 gdb_assert (closure
);
721 make_cleanup (cleanup_displaced_step_closure
, closure
);
723 /* Resume execution at the copy. */
724 regcache_write_pc (regcache
, copy
);
726 discard_cleanups (old_cleanups
);
729 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to 0x%s\n",
732 /* Save the information we need to fix things up if the step
734 displaced_step_ptid
= ptid
;
735 displaced_step_gdbarch
= gdbarch
;
736 displaced_step_closure
= closure
;
737 displaced_step_original
= original
;
738 displaced_step_copy
= copy
;
743 displaced_step_clear_cleanup (void *ignore
)
745 displaced_step_clear ();
749 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
, const gdb_byte
*myaddr
, int len
)
751 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
752 inferior_ptid
= ptid
;
753 write_memory (memaddr
, myaddr
, len
);
754 do_cleanups (ptid_cleanup
);
758 displaced_step_fixup (ptid_t event_ptid
, enum target_signal signal
)
760 struct cleanup
*old_cleanups
;
762 /* Was this event for the pid we displaced? */
763 if (ptid_equal (displaced_step_ptid
, null_ptid
)
764 || ! ptid_equal (displaced_step_ptid
, event_ptid
))
767 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, 0);
769 /* Restore the contents of the copy area. */
771 ULONGEST len
= gdbarch_max_insn_length (displaced_step_gdbarch
);
772 write_memory_ptid (displaced_step_ptid
, displaced_step_copy
,
773 displaced_step_saved_copy
, len
);
775 fprintf_unfiltered (gdb_stdlog
, "displaced: restored 0x%s\n",
776 paddr_nz (displaced_step_copy
));
779 /* Did the instruction complete successfully? */
780 if (signal
== TARGET_SIGNAL_TRAP
)
782 /* Fix up the resulting state. */
783 gdbarch_displaced_step_fixup (displaced_step_gdbarch
,
784 displaced_step_closure
,
785 displaced_step_original
,
787 get_thread_regcache (displaced_step_ptid
));
791 /* Since the instruction didn't complete, all we can do is
793 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
794 CORE_ADDR pc
= regcache_read_pc (regcache
);
795 pc
= displaced_step_original
+ (pc
- displaced_step_copy
);
796 regcache_write_pc (regcache
, pc
);
799 do_cleanups (old_cleanups
);
801 /* Are there any pending displaced stepping requests? If so, run
803 if (displaced_step_request_queue
)
805 struct displaced_step_request
*head
;
808 head
= displaced_step_request_queue
;
810 displaced_step_request_queue
= head
->next
;
814 fprintf_unfiltered (gdb_stdlog
,
815 "displaced: stepping queued %s now\n",
816 target_pid_to_str (ptid
));
819 displaced_step_ptid
= null_ptid
;
820 displaced_step_prepare (ptid
);
821 target_resume (ptid
, 1, TARGET_SIGNAL_0
);
825 /* Update global variables holding ptids to hold NEW_PTID if they were
828 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
830 struct displaced_step_request
*it
;
832 if (ptid_equal (inferior_ptid
, old_ptid
))
833 inferior_ptid
= new_ptid
;
835 if (ptid_equal (singlestep_ptid
, old_ptid
))
836 singlestep_ptid
= new_ptid
;
838 if (ptid_equal (displaced_step_ptid
, old_ptid
))
839 displaced_step_ptid
= new_ptid
;
841 if (ptid_equal (deferred_step_ptid
, old_ptid
))
842 deferred_step_ptid
= new_ptid
;
844 for (it
= displaced_step_request_queue
; it
; it
= it
->next
)
845 if (ptid_equal (it
->ptid
, old_ptid
))
852 /* Things to clean up if we QUIT out of resume (). */
854 resume_cleanups (void *ignore
)
859 static const char schedlock_off
[] = "off";
860 static const char schedlock_on
[] = "on";
861 static const char schedlock_step
[] = "step";
862 static const char *scheduler_enums
[] = {
868 static const char *scheduler_mode
= schedlock_off
;
870 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
871 struct cmd_list_element
*c
, const char *value
)
873 fprintf_filtered (file
, _("\
874 Mode for locking scheduler during execution is \"%s\".\n"),
879 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
881 if (!target_can_lock_scheduler
)
883 scheduler_mode
= schedlock_off
;
884 error (_("Target '%s' cannot support this command."), target_shortname
);
889 /* Resume the inferior, but allow a QUIT. This is useful if the user
890 wants to interrupt some lengthy single-stepping operation
891 (for child processes, the SIGINT goes to the inferior, and so
892 we get a SIGINT random_signal, but for remote debugging and perhaps
893 other targets, that's not true).
895 STEP nonzero if we should step (zero to continue instead).
896 SIG is the signal to give the inferior (zero for none). */
898 resume (int step
, enum target_signal sig
)
900 int should_resume
= 1;
901 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
902 struct regcache
*regcache
= get_current_regcache ();
903 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
904 struct thread_info
*tp
= inferior_thread ();
905 CORE_ADDR pc
= regcache_read_pc (regcache
);
909 fprintf_unfiltered (gdb_stdlog
,
910 "infrun: resume (step=%d, signal=%d), "
911 "trap_expected=%d\n",
912 step
, sig
, tp
->trap_expected
);
914 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
915 over an instruction that causes a page fault without triggering
916 a hardware watchpoint. The kernel properly notices that it shouldn't
917 stop, because the hardware watchpoint is not triggered, but it forgets
918 the step request and continues the program normally.
919 Work around the problem by removing hardware watchpoints if a step is
920 requested, GDB will check for a hardware watchpoint trigger after the
922 if (CANNOT_STEP_HW_WATCHPOINTS
&& step
)
923 remove_hw_watchpoints ();
926 /* Normally, by the time we reach `resume', the breakpoints are either
927 removed or inserted, as appropriate. The exception is if we're sitting
928 at a permanent breakpoint; we need to step over it, but permanent
929 breakpoints can't be removed. So we have to test for it here. */
930 if (breakpoint_here_p (pc
) == permanent_breakpoint_here
)
932 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
933 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
936 The program is stopped at a permanent breakpoint, but GDB does not know\n\
937 how to step past a permanent breakpoint on this architecture. Try using\n\
938 a command like `return' or `jump' to continue execution."));
941 /* If enabled, step over breakpoints by executing a copy of the
942 instruction at a different address.
944 We can't use displaced stepping when we have a signal to deliver;
945 the comments for displaced_step_prepare explain why. The
946 comments in the handle_inferior event for dealing with 'random
947 signals' explain what we do instead. */
948 if (use_displaced_stepping (gdbarch
)
950 && sig
== TARGET_SIGNAL_0
)
952 if (!displaced_step_prepare (inferior_ptid
))
954 /* Got placed in displaced stepping queue. Will be resumed
955 later when all the currently queued displaced stepping
956 requests finish. The thread is not executing at this point,
957 and the call to set_executing will be made later. But we
958 need to call set_running here, since from frontend point of view,
959 the thread is running. */
960 set_running (inferior_ptid
, 1);
961 discard_cleanups (old_cleanups
);
966 if (step
&& gdbarch_software_single_step_p (gdbarch
))
968 /* Do it the hard way, w/temp breakpoints */
969 if (gdbarch_software_single_step (gdbarch
, get_current_frame ()))
971 /* ...and don't ask hardware to do it. */
973 /* and do not pull these breakpoints until after a `wait' in
974 `wait_for_inferior' */
975 singlestep_breakpoints_inserted_p
= 1;
976 singlestep_ptid
= inferior_ptid
;
981 /* If there were any forks/vforks/execs that were caught and are
982 now to be followed, then do so. */
983 switch (pending_follow
.kind
)
985 case TARGET_WAITKIND_FORKED
:
986 case TARGET_WAITKIND_VFORKED
:
987 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
992 case TARGET_WAITKIND_EXECD
:
993 /* follow_exec is called as soon as the exec event is seen. */
994 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
1001 /* Install inferior's terminal modes. */
1002 target_terminal_inferior ();
1008 resume_ptid
= RESUME_ALL
; /* Default */
1010 /* If STEP is set, it's a request to use hardware stepping
1011 facilities. But in that case, we should never
1012 use singlestep breakpoint. */
1013 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1015 if (singlestep_breakpoints_inserted_p
1016 && stepping_past_singlestep_breakpoint
)
1018 /* The situation here is as follows. In thread T1 we wanted to
1019 single-step. Lacking hardware single-stepping we've
1020 set breakpoint at the PC of the next instruction -- call it
1021 P. After resuming, we've hit that breakpoint in thread T2.
1022 Now we've removed original breakpoint, inserted breakpoint
1023 at P+1, and try to step to advance T2 past breakpoint.
1024 We need to step only T2, as if T1 is allowed to freely run,
1025 it can run past P, and if other threads are allowed to run,
1026 they can hit breakpoint at P+1, and nested hits of single-step
1027 breakpoints is not something we'd want -- that's complicated
1028 to support, and has no value. */
1029 resume_ptid
= inferior_ptid
;
1032 if ((step
|| singlestep_breakpoints_inserted_p
)
1033 && tp
->trap_expected
)
1035 /* We're allowing a thread to run past a breakpoint it has
1036 hit, by single-stepping the thread with the breakpoint
1037 removed. In which case, we need to single-step only this
1038 thread, and keep others stopped, as they can miss this
1039 breakpoint if allowed to run.
1041 The current code actually removes all breakpoints when
1042 doing this, not just the one being stepped over, so if we
1043 let other threads run, we can actually miss any
1044 breakpoint, not just the one at PC. */
1045 resume_ptid
= inferior_ptid
;
1050 /* With non-stop mode on, threads are always handled
1052 resume_ptid
= inferior_ptid
;
1054 else if ((scheduler_mode
== schedlock_on
)
1055 || (scheduler_mode
== schedlock_step
1056 && (step
|| singlestep_breakpoints_inserted_p
)))
1058 /* User-settable 'scheduler' mode requires solo thread resume. */
1059 resume_ptid
= inferior_ptid
;
1062 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1064 /* Most targets can step a breakpoint instruction, thus
1065 executing it normally. But if this one cannot, just
1066 continue and we will hit it anyway. */
1067 if (step
&& breakpoint_inserted_here_p (pc
))
1072 && use_displaced_stepping (gdbarch
)
1073 && tp
->trap_expected
)
1075 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1076 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1079 fprintf_unfiltered (gdb_stdlog
, "displaced: run 0x%s: ",
1080 paddr_nz (actual_pc
));
1081 read_memory (actual_pc
, buf
, sizeof (buf
));
1082 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1085 target_resume (resume_ptid
, step
, sig
);
1088 discard_cleanups (old_cleanups
);
1093 /* Clear out all variables saying what to do when inferior is continued.
1094 First do this, then set the ones you want, then call `proceed'. */
1097 clear_proceed_status (void)
1099 if (!ptid_equal (inferior_ptid
, null_ptid
))
1101 struct thread_info
*tp
= inferior_thread ();
1103 tp
->trap_expected
= 0;
1104 tp
->step_range_start
= 0;
1105 tp
->step_range_end
= 0;
1106 tp
->step_frame_id
= null_frame_id
;
1107 tp
->step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1110 stop_after_trap
= 0;
1111 stop_soon
= NO_STOP_QUIETLY
;
1112 proceed_to_finish
= 0;
1113 breakpoint_proceeded
= 1; /* We're about to proceed... */
1117 regcache_xfree (stop_registers
);
1118 stop_registers
= NULL
;
1121 /* Discard any remaining commands or status from previous stop. */
1122 bpstat_clear (&stop_bpstat
);
1125 /* This should be suitable for any targets that support threads. */
1128 prepare_to_proceed (int step
)
1131 struct target_waitstatus wait_status
;
1133 /* Get the last target status returned by target_wait(). */
1134 get_last_target_status (&wait_ptid
, &wait_status
);
1136 /* Make sure we were stopped at a breakpoint. */
1137 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
1138 || wait_status
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1143 /* Switched over from WAIT_PID. */
1144 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
1145 && !ptid_equal (inferior_ptid
, wait_ptid
))
1147 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
1149 if (breakpoint_here_p (regcache_read_pc (regcache
)))
1151 /* If stepping, remember current thread to switch back to. */
1153 deferred_step_ptid
= inferior_ptid
;
1155 /* Switch back to WAIT_PID thread. */
1156 switch_to_thread (wait_ptid
);
1158 /* We return 1 to indicate that there is a breakpoint here,
1159 so we need to step over it before continuing to avoid
1160 hitting it straight away. */
1168 /* Basic routine for continuing the program in various fashions.
1170 ADDR is the address to resume at, or -1 for resume where stopped.
1171 SIGGNAL is the signal to give it, or 0 for none,
1172 or -1 for act according to how it stopped.
1173 STEP is nonzero if should trap after one instruction.
1174 -1 means return after that and print nothing.
1175 You should probably set various step_... variables
1176 before calling here, if you are stepping.
1178 You should call clear_proceed_status before calling proceed. */
1181 proceed (CORE_ADDR addr
, enum target_signal siggnal
, int step
)
1183 struct regcache
*regcache
= get_current_regcache ();
1184 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1185 struct thread_info
*tp
;
1186 CORE_ADDR pc
= regcache_read_pc (regcache
);
1190 step_start_function
= find_pc_function (pc
);
1192 stop_after_trap
= 1;
1194 if (addr
== (CORE_ADDR
) -1)
1196 if (pc
== stop_pc
&& breakpoint_here_p (pc
))
1197 /* There is a breakpoint at the address we will resume at,
1198 step one instruction before inserting breakpoints so that
1199 we do not stop right away (and report a second hit at this
1202 else if (gdbarch_single_step_through_delay_p (gdbarch
)
1203 && gdbarch_single_step_through_delay (gdbarch
,
1204 get_current_frame ()))
1205 /* We stepped onto an instruction that needs to be stepped
1206 again before re-inserting the breakpoint, do so. */
1211 regcache_write_pc (regcache
, addr
);
1215 fprintf_unfiltered (gdb_stdlog
,
1216 "infrun: proceed (addr=0x%s, signal=%d, step=%d)\n",
1217 paddr_nz (addr
), siggnal
, step
);
1220 /* In non-stop, each thread is handled individually. The context
1221 must already be set to the right thread here. */
1225 /* In a multi-threaded task we may select another thread and
1226 then continue or step.
1228 But if the old thread was stopped at a breakpoint, it will
1229 immediately cause another breakpoint stop without any
1230 execution (i.e. it will report a breakpoint hit incorrectly).
1231 So we must step over it first.
1233 prepare_to_proceed checks the current thread against the
1234 thread that reported the most recent event. If a step-over
1235 is required it returns TRUE and sets the current thread to
1237 if (prepare_to_proceed (step
))
1241 /* prepare_to_proceed may change the current thread. */
1242 tp
= inferior_thread ();
1246 tp
->trap_expected
= 1;
1247 /* If displaced stepping is enabled, we can step over the
1248 breakpoint without hitting it, so leave all breakpoints
1249 inserted. Otherwise we need to disable all breakpoints, step
1250 one instruction, and then re-add them when that step is
1252 if (!use_displaced_stepping (gdbarch
))
1253 remove_breakpoints ();
1256 /* We can insert breakpoints if we're not trying to step over one,
1257 or if we are stepping over one but we're using displaced stepping
1259 if (! tp
->trap_expected
|| use_displaced_stepping (gdbarch
))
1260 insert_breakpoints ();
1262 if (siggnal
!= TARGET_SIGNAL_DEFAULT
)
1263 stop_signal
= siggnal
;
1264 /* If this signal should not be seen by program,
1265 give it zero. Used for debugging signals. */
1266 else if (!signal_program
[stop_signal
])
1267 stop_signal
= TARGET_SIGNAL_0
;
1269 annotate_starting ();
1271 /* Make sure that output from GDB appears before output from the
1273 gdb_flush (gdb_stdout
);
1275 /* Refresh prev_pc value just prior to resuming. This used to be
1276 done in stop_stepping, however, setting prev_pc there did not handle
1277 scenarios such as inferior function calls or returning from
1278 a function via the return command. In those cases, the prev_pc
1279 value was not set properly for subsequent commands. The prev_pc value
1280 is used to initialize the starting line number in the ecs. With an
1281 invalid value, the gdb next command ends up stopping at the position
1282 represented by the next line table entry past our start position.
1283 On platforms that generate one line table entry per line, this
1284 is not a problem. However, on the ia64, the compiler generates
1285 extraneous line table entries that do not increase the line number.
1286 When we issue the gdb next command on the ia64 after an inferior call
1287 or a return command, we often end up a few instructions forward, still
1288 within the original line we started.
1290 An attempt was made to have init_execution_control_state () refresh
1291 the prev_pc value before calculating the line number. This approach
1292 did not work because on platforms that use ptrace, the pc register
1293 cannot be read unless the inferior is stopped. At that point, we
1294 are not guaranteed the inferior is stopped and so the regcache_read_pc ()
1295 call can fail. Setting the prev_pc value here ensures the value is
1296 updated correctly when the inferior is stopped. */
1297 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
1299 /* Fill in with reasonable starting values. */
1300 init_thread_stepping_state (tp
);
1302 /* Reset to normal state. */
1303 init_infwait_state ();
1305 /* Resume inferior. */
1306 resume (oneproc
|| step
|| bpstat_should_step (), stop_signal
);
1308 /* Wait for it to stop (if not standalone)
1309 and in any case decode why it stopped, and act accordingly. */
1310 /* Do this only if we are not using the event loop, or if the target
1311 does not support asynchronous execution. */
1312 if (!target_can_async_p ())
1314 wait_for_inferior (0);
1320 /* Start remote-debugging of a machine over a serial link. */
1323 start_remote (int from_tty
)
1325 init_wait_for_inferior ();
1326 stop_soon
= STOP_QUIETLY_REMOTE
;
1328 /* Always go on waiting for the target, regardless of the mode. */
1329 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1330 indicate to wait_for_inferior that a target should timeout if
1331 nothing is returned (instead of just blocking). Because of this,
1332 targets expecting an immediate response need to, internally, set
1333 things up so that the target_wait() is forced to eventually
1335 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1336 differentiate to its caller what the state of the target is after
1337 the initial open has been performed. Here we're assuming that
1338 the target has stopped. It should be possible to eventually have
1339 target_open() return to the caller an indication that the target
1340 is currently running and GDB state should be set to the same as
1341 for an async run. */
1342 wait_for_inferior (0);
1344 /* Now that the inferior has stopped, do any bookkeeping like
1345 loading shared libraries. We want to do this before normal_stop,
1346 so that the displayed frame is up to date. */
1347 post_create_inferior (¤t_target
, from_tty
);
1352 /* Initialize static vars when a new inferior begins. */
1355 init_wait_for_inferior (void)
1357 /* These are meaningless until the first time through wait_for_inferior. */
1359 breakpoint_init_inferior (inf_starting
);
1361 /* Don't confuse first call to proceed(). */
1362 stop_signal
= TARGET_SIGNAL_0
;
1364 /* The first resume is not following a fork/vfork/exec. */
1365 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
; /* I.e., none. */
1367 clear_proceed_status ();
1369 stepping_past_singlestep_breakpoint
= 0;
1370 deferred_step_ptid
= null_ptid
;
1372 target_last_wait_ptid
= minus_one_ptid
;
1374 previous_inferior_ptid
= null_ptid
;
1375 init_infwait_state ();
1377 displaced_step_clear ();
1381 /* This enum encodes possible reasons for doing a target_wait, so that
1382 wfi can call target_wait in one place. (Ultimately the call will be
1383 moved out of the infinite loop entirely.) */
1387 infwait_normal_state
,
1388 infwait_thread_hop_state
,
1389 infwait_step_watch_state
,
1390 infwait_nonstep_watch_state
1393 /* Why did the inferior stop? Used to print the appropriate messages
1394 to the interface from within handle_inferior_event(). */
1395 enum inferior_stop_reason
1397 /* Step, next, nexti, stepi finished. */
1399 /* Inferior terminated by signal. */
1401 /* Inferior exited. */
1403 /* Inferior received signal, and user asked to be notified. */
1407 /* The PTID we'll do a target_wait on.*/
1410 /* Current inferior wait state. */
1411 enum infwait_states infwait_state
;
1413 /* Data to be passed around while handling an event. This data is
1414 discarded between events. */
1415 struct execution_control_state
1418 /* The thread that got the event, if this was a thread event; NULL
1420 struct thread_info
*event_thread
;
1422 struct target_waitstatus ws
;
1424 CORE_ADDR stop_func_start
;
1425 CORE_ADDR stop_func_end
;
1426 char *stop_func_name
;
1427 int new_thread_event
;
1431 void init_execution_control_state (struct execution_control_state
*ecs
);
1433 void handle_inferior_event (struct execution_control_state
*ecs
);
1435 static void step_into_function (struct execution_control_state
*ecs
);
1436 static void insert_step_resume_breakpoint_at_frame (struct frame_info
*step_frame
);
1437 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
1438 static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
1439 struct frame_id sr_id
);
1440 static void insert_longjmp_resume_breakpoint (CORE_ADDR
);
1442 static void stop_stepping (struct execution_control_state
*ecs
);
1443 static void prepare_to_wait (struct execution_control_state
*ecs
);
1444 static void keep_going (struct execution_control_state
*ecs
);
1445 static void print_stop_reason (enum inferior_stop_reason stop_reason
,
1448 /* Callback for iterate_over_threads. */
1451 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
1453 if (is_exited (info
->ptid
))
1456 delete_step_resume_breakpoint (info
);
1460 /* In all-stop, delete the step resume breakpoint of any thread that
1461 had one. In non-stop, delete the step resume breakpoint of the
1462 thread that just stopped. */
1465 delete_step_thread_step_resume_breakpoint (void)
1467 if (!target_has_execution
1468 || ptid_equal (inferior_ptid
, null_ptid
))
1469 /* If the inferior has exited, we have already deleted the step
1470 resume breakpoints out of GDB's lists. */
1475 /* If in non-stop mode, only delete the step-resume or
1476 longjmp-resume breakpoint of the thread that just stopped
1478 struct thread_info
*tp
= inferior_thread ();
1479 delete_step_resume_breakpoint (tp
);
1482 /* In all-stop mode, delete all step-resume and longjmp-resume
1483 breakpoints of any thread that had them. */
1484 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
1487 /* A cleanup wrapper. */
1490 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
1492 delete_step_thread_step_resume_breakpoint ();
1495 /* Wait for control to return from inferior to debugger.
1497 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
1498 as if they were SIGTRAP signals. This can be useful during
1499 the startup sequence on some targets such as HP/UX, where
1500 we receive an EXEC event instead of the expected SIGTRAP.
1502 If inferior gets a signal, we may decide to start it up again
1503 instead of returning. That is why there is a loop in this function.
1504 When this function actually returns it means the inferior
1505 should be left stopped and GDB should read more commands. */
1508 wait_for_inferior (int treat_exec_as_sigtrap
)
1510 struct cleanup
*old_cleanups
;
1511 struct execution_control_state ecss
;
1512 struct execution_control_state
*ecs
;
1516 (gdb_stdlog
, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
1517 treat_exec_as_sigtrap
);
1520 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
1523 memset (ecs
, 0, sizeof (*ecs
));
1525 overlay_cache_invalid
= 1;
1527 /* We'll update this if & when we switch to a new thread. */
1528 previous_inferior_ptid
= inferior_ptid
;
1530 /* We have to invalidate the registers BEFORE calling target_wait
1531 because they can be loaded from the target while in target_wait.
1532 This makes remote debugging a bit more efficient for those
1533 targets that provide critical registers as part of their normal
1534 status mechanism. */
1536 registers_changed ();
1540 if (deprecated_target_wait_hook
)
1541 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
);
1543 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
);
1545 ecs
->event_thread
= find_thread_pid (ecs
->ptid
);
1547 if (treat_exec_as_sigtrap
&& ecs
->ws
.kind
== TARGET_WAITKIND_EXECD
)
1549 xfree (ecs
->ws
.value
.execd_pathname
);
1550 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
1551 ecs
->ws
.value
.sig
= TARGET_SIGNAL_TRAP
;
1554 /* Now figure out what to do with the result of the result. */
1555 handle_inferior_event (ecs
);
1557 if (!ecs
->wait_some_more
)
1561 do_cleanups (old_cleanups
);
1564 /* Asynchronous version of wait_for_inferior. It is called by the
1565 event loop whenever a change of state is detected on the file
1566 descriptor corresponding to the target. It can be called more than
1567 once to complete a single execution command. In such cases we need
1568 to keep the state in a global variable ECSS. If it is the last time
1569 that this function is called for a single execution command, then
1570 report to the user that the inferior has stopped, and do the
1571 necessary cleanups. */
1574 fetch_inferior_event (void *client_data
)
1576 struct execution_control_state ecss
;
1577 struct execution_control_state
*ecs
= &ecss
;
1578 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
1579 int was_sync
= sync_execution
;
1581 memset (ecs
, 0, sizeof (*ecs
));
1583 overlay_cache_invalid
= 1;
1585 /* We can only rely on wait_for_more being correct before handling
1586 the event in all-stop, but previous_inferior_ptid isn't used in
1588 if (!ecs
->wait_some_more
)
1589 /* We'll update this if & when we switch to a new thread. */
1590 previous_inferior_ptid
= inferior_ptid
;
1593 /* In non-stop mode, the user/frontend should not notice a thread
1594 switch due to internal events. Make sure we reverse to the
1595 user selected thread and frame after handling the event and
1596 running any breakpoint commands. */
1597 make_cleanup_restore_current_thread ();
1599 /* We have to invalidate the registers BEFORE calling target_wait
1600 because they can be loaded from the target while in target_wait.
1601 This makes remote debugging a bit more efficient for those
1602 targets that provide critical registers as part of their normal
1603 status mechanism. */
1605 registers_changed ();
1607 if (deprecated_target_wait_hook
)
1609 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
);
1611 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
);
1614 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
1615 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1616 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
1617 /* In non-stop mode, each thread is handled individually. Switch
1618 early, so the global state is set correctly for this
1620 context_switch (ecs
->ptid
);
1622 ecs
->event_thread
= find_thread_pid (ecs
->ptid
);
1624 /* Now figure out what to do with the result of the result. */
1625 handle_inferior_event (ecs
);
1627 if (!ecs
->wait_some_more
)
1629 delete_step_thread_step_resume_breakpoint ();
1631 if (stop_soon
== NO_STOP_QUIETLY
)
1634 if (step_multi
&& stop_step
)
1635 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
1637 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
1640 /* Revert thread and frame. */
1641 do_cleanups (old_chain
);
1643 /* If the inferior was in sync execution mode, and now isn't,
1644 restore the prompt. */
1645 if (was_sync
&& !sync_execution
)
1646 display_gdb_prompt (0);
1649 /* Prepare an execution control state for looping through a
1650 wait_for_inferior-type loop. */
1653 init_execution_control_state (struct execution_control_state
*ecs
)
1655 ecs
->random_signal
= 0;
1658 /* Clear context switchable stepping state. */
1661 init_thread_stepping_state (struct thread_info
*tss
)
1663 struct symtab_and_line sal
;
1665 tss
->stepping_over_breakpoint
= 0;
1666 tss
->step_after_step_resume_breakpoint
= 0;
1667 tss
->stepping_through_solib_after_catch
= 0;
1668 tss
->stepping_through_solib_catchpoints
= NULL
;
1670 sal
= find_pc_line (tss
->prev_pc
, 0);
1671 tss
->current_line
= sal
.line
;
1672 tss
->current_symtab
= sal
.symtab
;
1675 /* Return the cached copy of the last pid/waitstatus returned by
1676 target_wait()/deprecated_target_wait_hook(). The data is actually
1677 cached by handle_inferior_event(), which gets called immediately
1678 after target_wait()/deprecated_target_wait_hook(). */
1681 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
1683 *ptidp
= target_last_wait_ptid
;
1684 *status
= target_last_waitstatus
;
1688 nullify_last_target_wait_ptid (void)
1690 target_last_wait_ptid
= minus_one_ptid
;
1693 /* Switch thread contexts, maintaining "infrun state". */
1696 context_switch (ptid_t ptid
)
1698 /* Caution: it may happen that the new thread (or the old one!)
1699 is not in the thread list. In this case we must not attempt
1700 to "switch context", or we run the risk that our context may
1701 be lost. This may happen as a result of the target module
1702 mishandling thread creation. */
1706 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
1707 target_pid_to_str (inferior_ptid
));
1708 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
1709 target_pid_to_str (ptid
));
1712 if (in_thread_list (inferior_ptid
) && in_thread_list (ptid
))
1713 { /* Perform infrun state context switch: */
1714 /* Save infrun state for the old thread. */
1715 save_infrun_state (inferior_ptid
,
1716 cmd_continuation
, intermediate_continuation
,
1723 /* Load infrun state for the new thread. */
1724 load_infrun_state (ptid
,
1725 &cmd_continuation
, &intermediate_continuation
,
1733 switch_to_thread (ptid
);
1736 /* Context switch to thread PTID. */
1738 context_switch_to (ptid_t ptid
)
1740 ptid_t current_ptid
= inferior_ptid
;
1742 /* Context switch to the new thread. */
1743 if (!ptid_equal (ptid
, inferior_ptid
))
1745 context_switch (ptid
);
1747 return current_ptid
;
1751 adjust_pc_after_break (struct execution_control_state
*ecs
)
1753 struct regcache
*regcache
;
1754 struct gdbarch
*gdbarch
;
1755 CORE_ADDR breakpoint_pc
;
1757 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
1758 we aren't, just return.
1760 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
1761 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
1762 implemented by software breakpoints should be handled through the normal
1765 NOTE drow/2004-01-31: On some targets, breakpoints may generate
1766 different signals (SIGILL or SIGEMT for instance), but it is less
1767 clear where the PC is pointing afterwards. It may not match
1768 gdbarch_decr_pc_after_break. I don't know any specific target that
1769 generates these signals at breakpoints (the code has been in GDB since at
1770 least 1992) so I can not guess how to handle them here.
1772 In earlier versions of GDB, a target with
1773 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
1774 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
1775 target with both of these set in GDB history, and it seems unlikely to be
1776 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
1778 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
1781 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1784 /* If this target does not decrement the PC after breakpoints, then
1785 we have nothing to do. */
1786 regcache
= get_thread_regcache (ecs
->ptid
);
1787 gdbarch
= get_regcache_arch (regcache
);
1788 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
1791 /* Find the location where (if we've hit a breakpoint) the
1792 breakpoint would be. */
1793 breakpoint_pc
= regcache_read_pc (regcache
)
1794 - gdbarch_decr_pc_after_break (gdbarch
);
1796 /* Check whether there actually is a software breakpoint inserted
1797 at that location. */
1798 if (software_breakpoint_inserted_here_p (breakpoint_pc
))
1800 /* When using hardware single-step, a SIGTRAP is reported for both
1801 a completed single-step and a software breakpoint. Need to
1802 differentiate between the two, as the latter needs adjusting
1803 but the former does not.
1805 The SIGTRAP can be due to a completed hardware single-step only if
1806 - we didn't insert software single-step breakpoints
1807 - the thread to be examined is still the current thread
1808 - this thread is currently being stepped
1810 If any of these events did not occur, we must have stopped due
1811 to hitting a software breakpoint, and have to back up to the
1814 As a special case, we could have hardware single-stepped a
1815 software breakpoint. In this case (prev_pc == breakpoint_pc),
1816 we also need to back up to the breakpoint address. */
1818 if (singlestep_breakpoints_inserted_p
1819 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
1820 || !currently_stepping (ecs
->event_thread
)
1821 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
1822 regcache_write_pc (regcache
, breakpoint_pc
);
1827 init_infwait_state (void)
1829 waiton_ptid
= pid_to_ptid (-1);
1830 infwait_state
= infwait_normal_state
;
1834 error_is_running (void)
1837 Cannot execute this command while the selected thread is running."));
1841 ensure_not_running (void)
1843 if (is_running (inferior_ptid
))
1844 error_is_running ();
1847 /* Given an execution control state that has been freshly filled in
1848 by an event from the inferior, figure out what it means and take
1849 appropriate action. */
1852 handle_inferior_event (struct execution_control_state
*ecs
)
1854 int sw_single_step_trap_p
= 0;
1855 int stopped_by_watchpoint
;
1856 int stepped_after_stopped_by_watchpoint
= 0;
1857 struct symtab_and_line stop_pc_sal
;
1859 breakpoint_retire_moribund ();
1861 /* Cache the last pid/waitstatus. */
1862 target_last_wait_ptid
= ecs
->ptid
;
1863 target_last_waitstatus
= ecs
->ws
;
1865 /* Always clear state belonging to the previous time we stopped. */
1866 stop_stack_dummy
= 0;
1868 adjust_pc_after_break (ecs
);
1870 reinit_frame_cache ();
1872 /* If it's a new process, add it to the thread database */
1874 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
1875 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
1876 && !in_thread_list (ecs
->ptid
));
1878 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1879 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
1880 add_thread (ecs
->ptid
);
1882 if (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
1884 /* Mark the non-executing threads accordingly. */
1886 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
1887 || ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
1888 set_executing (pid_to_ptid (-1), 0);
1890 set_executing (ecs
->ptid
, 0);
1893 switch (infwait_state
)
1895 case infwait_thread_hop_state
:
1897 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
1898 /* Cancel the waiton_ptid. */
1899 waiton_ptid
= pid_to_ptid (-1);
1902 case infwait_normal_state
:
1904 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
1907 case infwait_step_watch_state
:
1909 fprintf_unfiltered (gdb_stdlog
,
1910 "infrun: infwait_step_watch_state\n");
1912 stepped_after_stopped_by_watchpoint
= 1;
1915 case infwait_nonstep_watch_state
:
1917 fprintf_unfiltered (gdb_stdlog
,
1918 "infrun: infwait_nonstep_watch_state\n");
1919 insert_breakpoints ();
1921 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1922 handle things like signals arriving and other things happening
1923 in combination correctly? */
1924 stepped_after_stopped_by_watchpoint
= 1;
1928 internal_error (__FILE__
, __LINE__
, _("bad switch"));
1930 infwait_state
= infwait_normal_state
;
1932 switch (ecs
->ws
.kind
)
1934 case TARGET_WAITKIND_LOADED
:
1936 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
1937 /* Ignore gracefully during startup of the inferior, as it might
1938 be the shell which has just loaded some objects, otherwise
1939 add the symbols for the newly loaded objects. Also ignore at
1940 the beginning of an attach or remote session; we will query
1941 the full list of libraries once the connection is
1943 if (stop_soon
== NO_STOP_QUIETLY
)
1945 /* Check for any newly added shared libraries if we're
1946 supposed to be adding them automatically. Switch
1947 terminal for any messages produced by
1948 breakpoint_re_set. */
1949 target_terminal_ours_for_output ();
1950 /* NOTE: cagney/2003-11-25: Make certain that the target
1951 stack's section table is kept up-to-date. Architectures,
1952 (e.g., PPC64), use the section table to perform
1953 operations such as address => section name and hence
1954 require the table to contain all sections (including
1955 those found in shared libraries). */
1956 /* NOTE: cagney/2003-11-25: Pass current_target and not
1957 exec_ops to SOLIB_ADD. This is because current GDB is
1958 only tooled to propagate section_table changes out from
1959 the "current_target" (see target_resize_to_sections), and
1960 not up from the exec stratum. This, of course, isn't
1961 right. "infrun.c" should only interact with the
1962 exec/process stratum, instead relying on the target stack
1963 to propagate relevant changes (stop, section table
1964 changed, ...) up to other layers. */
1966 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
1968 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
1970 target_terminal_inferior ();
1972 /* If requested, stop when the dynamic linker notifies
1973 gdb of events. This allows the user to get control
1974 and place breakpoints in initializer routines for
1975 dynamically loaded objects (among other things). */
1976 if (stop_on_solib_events
)
1978 stop_stepping (ecs
);
1982 /* NOTE drow/2007-05-11: This might be a good place to check
1983 for "catch load". */
1986 /* If we are skipping through a shell, or through shared library
1987 loading that we aren't interested in, resume the program. If
1988 we're running the program normally, also resume. But stop if
1989 we're attaching or setting up a remote connection. */
1990 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
1992 /* Loading of shared libraries might have changed breakpoint
1993 addresses. Make sure new breakpoints are inserted. */
1994 if (stop_soon
== NO_STOP_QUIETLY
1995 && !breakpoints_always_inserted_mode ())
1996 insert_breakpoints ();
1997 resume (0, TARGET_SIGNAL_0
);
1998 prepare_to_wait (ecs
);
2004 case TARGET_WAITKIND_SPURIOUS
:
2006 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
2007 resume (0, TARGET_SIGNAL_0
);
2008 prepare_to_wait (ecs
);
2011 case TARGET_WAITKIND_EXITED
:
2013 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
2014 target_terminal_ours (); /* Must do this before mourn anyway */
2015 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
2017 /* Record the exit code in the convenience variable $_exitcode, so
2018 that the user can inspect this again later. */
2019 set_internalvar (lookup_internalvar ("_exitcode"),
2020 value_from_longest (builtin_type_int
,
2021 (LONGEST
) ecs
->ws
.value
.integer
));
2022 gdb_flush (gdb_stdout
);
2023 target_mourn_inferior ();
2024 singlestep_breakpoints_inserted_p
= 0;
2025 stop_print_frame
= 0;
2026 stop_stepping (ecs
);
2029 case TARGET_WAITKIND_SIGNALLED
:
2031 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2032 stop_print_frame
= 0;
2033 stop_signal
= ecs
->ws
.value
.sig
;
2034 target_terminal_ours (); /* Must do this before mourn anyway */
2036 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2037 reach here unless the inferior is dead. However, for years
2038 target_kill() was called here, which hints that fatal signals aren't
2039 really fatal on some systems. If that's true, then some changes
2041 target_mourn_inferior ();
2043 print_stop_reason (SIGNAL_EXITED
, stop_signal
);
2044 singlestep_breakpoints_inserted_p
= 0;
2045 stop_stepping (ecs
);
2048 /* The following are the only cases in which we keep going;
2049 the above cases end in a continue or goto. */
2050 case TARGET_WAITKIND_FORKED
:
2051 case TARGET_WAITKIND_VFORKED
:
2053 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2054 stop_signal
= TARGET_SIGNAL_TRAP
;
2055 pending_follow
.kind
= ecs
->ws
.kind
;
2057 pending_follow
.fork_event
.parent_pid
= ecs
->ptid
;
2058 pending_follow
.fork_event
.child_pid
= ecs
->ws
.value
.related_pid
;
2060 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2062 context_switch (ecs
->ptid
);
2063 reinit_frame_cache ();
2066 stop_pc
= read_pc ();
2068 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2070 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2072 /* If no catchpoint triggered for this, then keep going. */
2073 if (ecs
->random_signal
)
2075 stop_signal
= TARGET_SIGNAL_0
;
2079 goto process_event_stop_test
;
2081 case TARGET_WAITKIND_EXECD
:
2083 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
2084 stop_signal
= TARGET_SIGNAL_TRAP
;
2086 pending_follow
.execd_pathname
=
2087 savestring (ecs
->ws
.value
.execd_pathname
,
2088 strlen (ecs
->ws
.value
.execd_pathname
));
2090 /* This causes the eventpoints and symbol table to be reset. Must
2091 do this now, before trying to determine whether to stop. */
2092 follow_exec (inferior_ptid
, pending_follow
.execd_pathname
);
2093 xfree (pending_follow
.execd_pathname
);
2095 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2098 /* The breakpoints module may need to touch the inferior's
2099 memory. Switch to the (stopped) event ptid
2101 ptid_t saved_inferior_ptid
= inferior_ptid
;
2102 inferior_ptid
= ecs
->ptid
;
2104 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2106 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2107 inferior_ptid
= saved_inferior_ptid
;
2110 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2112 context_switch (ecs
->ptid
);
2113 reinit_frame_cache ();
2116 /* If no catchpoint triggered for this, then keep going. */
2117 if (ecs
->random_signal
)
2119 stop_signal
= TARGET_SIGNAL_0
;
2123 goto process_event_stop_test
;
2125 /* Be careful not to try to gather much state about a thread
2126 that's in a syscall. It's frequently a losing proposition. */
2127 case TARGET_WAITKIND_SYSCALL_ENTRY
:
2129 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2130 resume (0, TARGET_SIGNAL_0
);
2131 prepare_to_wait (ecs
);
2134 /* Before examining the threads further, step this thread to
2135 get it entirely out of the syscall. (We get notice of the
2136 event when the thread is just on the verge of exiting a
2137 syscall. Stepping one instruction seems to get it back
2139 case TARGET_WAITKIND_SYSCALL_RETURN
:
2141 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2142 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
);
2143 prepare_to_wait (ecs
);
2146 case TARGET_WAITKIND_STOPPED
:
2148 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
2149 stop_signal
= ecs
->ws
.value
.sig
;
2152 /* We had an event in the inferior, but we are not interested
2153 in handling it at this level. The lower layers have already
2154 done what needs to be done, if anything.
2156 One of the possible circumstances for this is when the
2157 inferior produces output for the console. The inferior has
2158 not stopped, and we are ignoring the event. Another possible
2159 circumstance is any event which the lower level knows will be
2160 reported multiple times without an intervening resume. */
2161 case TARGET_WAITKIND_IGNORE
:
2163 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2164 prepare_to_wait (ecs
);
2168 if (ecs
->new_thread_event
)
2171 /* Non-stop assumes that the target handles adding new threads
2172 to the thread list. */
2173 internal_error (__FILE__
, __LINE__
, "\
2174 targets should add new threads to the thread list themselves in non-stop mode.");
2176 /* We may want to consider not doing a resume here in order to
2177 give the user a chance to play with the new thread. It might
2178 be good to make that a user-settable option. */
2180 /* At this point, all threads are stopped (happens automatically
2181 in either the OS or the native code). Therefore we need to
2182 continue all threads in order to make progress. */
2184 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
2185 prepare_to_wait (ecs
);
2189 /* Do we need to clean up the state of a thread that has completed a
2190 displaced single-step? (Doing so usually affects the PC, so do
2191 it here, before we set stop_pc.) */
2192 displaced_step_fixup (ecs
->ptid
, stop_signal
);
2194 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2198 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = 0x%s\n",
2199 paddr_nz (stop_pc
));
2200 if (STOPPED_BY_WATCHPOINT (&ecs
->ws
))
2203 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
2205 if (target_stopped_data_address (¤t_target
, &addr
))
2206 fprintf_unfiltered (gdb_stdlog
,
2207 "infrun: stopped data address = 0x%s\n",
2210 fprintf_unfiltered (gdb_stdlog
,
2211 "infrun: (no data address available)\n");
2215 if (stepping_past_singlestep_breakpoint
)
2217 gdb_assert (singlestep_breakpoints_inserted_p
);
2218 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
2219 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
2221 stepping_past_singlestep_breakpoint
= 0;
2223 /* We've either finished single-stepping past the single-step
2224 breakpoint, or stopped for some other reason. It would be nice if
2225 we could tell, but we can't reliably. */
2226 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2229 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
2230 /* Pull the single step breakpoints out of the target. */
2231 remove_single_step_breakpoints ();
2232 singlestep_breakpoints_inserted_p
= 0;
2234 ecs
->random_signal
= 0;
2236 context_switch (saved_singlestep_ptid
);
2237 if (deprecated_context_hook
)
2238 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2240 resume (1, TARGET_SIGNAL_0
);
2241 prepare_to_wait (ecs
);
2246 stepping_past_singlestep_breakpoint
= 0;
2248 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
2250 /* In non-stop mode, there's never a deferred_step_ptid set. */
2251 gdb_assert (!non_stop
);
2253 /* If we stopped for some other reason than single-stepping, ignore
2254 the fact that we were supposed to switch back. */
2255 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2257 struct thread_info
*tp
;
2260 fprintf_unfiltered (gdb_stdlog
,
2261 "infrun: handling deferred step\n");
2263 /* Pull the single step breakpoints out of the target. */
2264 if (singlestep_breakpoints_inserted_p
)
2266 remove_single_step_breakpoints ();
2267 singlestep_breakpoints_inserted_p
= 0;
2270 /* Note: We do not call context_switch at this point, as the
2271 context is already set up for stepping the original thread. */
2272 switch_to_thread (deferred_step_ptid
);
2273 deferred_step_ptid
= null_ptid
;
2274 /* Suppress spurious "Switching to ..." message. */
2275 previous_inferior_ptid
= inferior_ptid
;
2277 resume (1, TARGET_SIGNAL_0
);
2278 prepare_to_wait (ecs
);
2282 deferred_step_ptid
= null_ptid
;
2285 /* See if a thread hit a thread-specific breakpoint that was meant for
2286 another thread. If so, then step that thread past the breakpoint,
2289 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2291 int thread_hop_needed
= 0;
2293 /* Check if a regular breakpoint has been hit before checking
2294 for a potential single step breakpoint. Otherwise, GDB will
2295 not see this breakpoint hit when stepping onto breakpoints. */
2296 if (regular_breakpoint_inserted_here_p (stop_pc
))
2298 ecs
->random_signal
= 0;
2299 if (!breakpoint_thread_match (stop_pc
, ecs
->ptid
))
2300 thread_hop_needed
= 1;
2302 else if (singlestep_breakpoints_inserted_p
)
2304 /* We have not context switched yet, so this should be true
2305 no matter which thread hit the singlestep breakpoint. */
2306 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
2308 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
2310 target_pid_to_str (ecs
->ptid
));
2312 ecs
->random_signal
= 0;
2313 /* The call to in_thread_list is necessary because PTIDs sometimes
2314 change when we go from single-threaded to multi-threaded. If
2315 the singlestep_ptid is still in the list, assume that it is
2316 really different from ecs->ptid. */
2317 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
2318 && in_thread_list (singlestep_ptid
))
2320 /* If the PC of the thread we were trying to single-step
2321 has changed, discard this event (which we were going
2322 to ignore anyway), and pretend we saw that thread
2323 trap. This prevents us continuously moving the
2324 single-step breakpoint forward, one instruction at a
2325 time. If the PC has changed, then the thread we were
2326 trying to single-step has trapped or been signalled,
2327 but the event has not been reported to GDB yet.
2329 There might be some cases where this loses signal
2330 information, if a signal has arrived at exactly the
2331 same time that the PC changed, but this is the best
2332 we can do with the information available. Perhaps we
2333 should arrange to report all events for all threads
2334 when they stop, or to re-poll the remote looking for
2335 this particular thread (i.e. temporarily enable
2338 CORE_ADDR new_singlestep_pc
2339 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
2341 if (new_singlestep_pc
!= singlestep_pc
)
2344 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
2345 " but expected thread advanced also\n");
2347 /* The current context still belongs to
2348 singlestep_ptid. Don't swap here, since that's
2349 the context we want to use. Just fudge our
2350 state and continue. */
2351 ecs
->ptid
= singlestep_ptid
;
2352 ecs
->event_thread
= find_thread_pid (ecs
->ptid
);
2353 stop_pc
= new_singlestep_pc
;
2358 fprintf_unfiltered (gdb_stdlog
,
2359 "infrun: unexpected thread\n");
2361 thread_hop_needed
= 1;
2362 stepping_past_singlestep_breakpoint
= 1;
2363 saved_singlestep_ptid
= singlestep_ptid
;
2368 if (thread_hop_needed
)
2370 int remove_status
= 0;
2373 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
2375 /* Saw a breakpoint, but it was hit by the wrong thread.
2378 if (singlestep_breakpoints_inserted_p
)
2380 /* Pull the single step breakpoints out of the target. */
2381 remove_single_step_breakpoints ();
2382 singlestep_breakpoints_inserted_p
= 0;
2385 /* If the arch can displace step, don't remove the
2387 if (!use_displaced_stepping (current_gdbarch
))
2388 remove_status
= remove_breakpoints ();
2390 /* Did we fail to remove breakpoints? If so, try
2391 to set the PC past the bp. (There's at least
2392 one situation in which we can fail to remove
2393 the bp's: On HP-UX's that use ttrace, we can't
2394 change the address space of a vforking child
2395 process until the child exits (well, okay, not
2396 then either :-) or execs. */
2397 if (remove_status
!= 0)
2398 error (_("Cannot step over breakpoint hit in wrong thread"));
2401 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
2402 context_switch (ecs
->ptid
);
2406 /* Only need to require the next event from this
2407 thread in all-stop mode. */
2408 waiton_ptid
= ecs
->ptid
;
2409 infwait_state
= infwait_thread_hop_state
;
2412 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2414 registers_changed ();
2418 else if (singlestep_breakpoints_inserted_p
)
2420 sw_single_step_trap_p
= 1;
2421 ecs
->random_signal
= 0;
2425 ecs
->random_signal
= 1;
2427 /* See if something interesting happened to the non-current thread. If
2428 so, then switch to that thread. */
2429 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2432 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
2434 context_switch (ecs
->ptid
);
2436 if (deprecated_context_hook
)
2437 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2440 if (singlestep_breakpoints_inserted_p
)
2442 /* Pull the single step breakpoints out of the target. */
2443 remove_single_step_breakpoints ();
2444 singlestep_breakpoints_inserted_p
= 0;
2447 if (stepped_after_stopped_by_watchpoint
)
2448 stopped_by_watchpoint
= 0;
2450 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
2452 /* If necessary, step over this watchpoint. We'll be back to display
2454 if (stopped_by_watchpoint
2455 && (HAVE_STEPPABLE_WATCHPOINT
2456 || gdbarch_have_nonsteppable_watchpoint (current_gdbarch
)))
2458 /* At this point, we are stopped at an instruction which has
2459 attempted to write to a piece of memory under control of
2460 a watchpoint. The instruction hasn't actually executed
2461 yet. If we were to evaluate the watchpoint expression
2462 now, we would get the old value, and therefore no change
2463 would seem to have occurred.
2465 In order to make watchpoints work `right', we really need
2466 to complete the memory write, and then evaluate the
2467 watchpoint expression. We do this by single-stepping the
2470 It may not be necessary to disable the watchpoint to stop over
2471 it. For example, the PA can (with some kernel cooperation)
2472 single step over a watchpoint without disabling the watchpoint.
2474 It is far more common to need to disable a watchpoint to step
2475 the inferior over it. If we have non-steppable watchpoints,
2476 we must disable the current watchpoint; it's simplest to
2477 disable all watchpoints and breakpoints. */
2479 if (!HAVE_STEPPABLE_WATCHPOINT
)
2480 remove_breakpoints ();
2481 registers_changed ();
2482 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
); /* Single step */
2483 waiton_ptid
= ecs
->ptid
;
2484 if (HAVE_STEPPABLE_WATCHPOINT
)
2485 infwait_state
= infwait_step_watch_state
;
2487 infwait_state
= infwait_nonstep_watch_state
;
2488 prepare_to_wait (ecs
);
2492 ecs
->stop_func_start
= 0;
2493 ecs
->stop_func_end
= 0;
2494 ecs
->stop_func_name
= 0;
2495 /* Don't care about return value; stop_func_start and stop_func_name
2496 will both be 0 if it doesn't work. */
2497 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
2498 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
2499 ecs
->stop_func_start
2500 += gdbarch_deprecated_function_start_offset (current_gdbarch
);
2501 ecs
->event_thread
->stepping_over_breakpoint
= 0;
2502 bpstat_clear (&stop_bpstat
);
2504 stop_print_frame
= 1;
2505 ecs
->random_signal
= 0;
2506 stopped_by_random_signal
= 0;
2508 if (stop_signal
== TARGET_SIGNAL_TRAP
2509 && ecs
->event_thread
->trap_expected
2510 && gdbarch_single_step_through_delay_p (current_gdbarch
)
2511 && currently_stepping (ecs
->event_thread
))
2513 /* We're trying to step off a breakpoint. Turns out that we're
2514 also on an instruction that needs to be stepped multiple
2515 times before it's been fully executing. E.g., architectures
2516 with a delay slot. It needs to be stepped twice, once for
2517 the instruction and once for the delay slot. */
2518 int step_through_delay
2519 = gdbarch_single_step_through_delay (current_gdbarch
,
2520 get_current_frame ());
2521 if (debug_infrun
&& step_through_delay
)
2522 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
2523 if (ecs
->event_thread
->step_range_end
== 0 && step_through_delay
)
2525 /* The user issued a continue when stopped at a breakpoint.
2526 Set up for another trap and get out of here. */
2527 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2531 else if (step_through_delay
)
2533 /* The user issued a step when stopped at a breakpoint.
2534 Maybe we should stop, maybe we should not - the delay
2535 slot *might* correspond to a line of source. In any
2536 case, don't decide that here, just set
2537 ecs->stepping_over_breakpoint, making sure we
2538 single-step again before breakpoints are re-inserted. */
2539 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2543 /* Look at the cause of the stop, and decide what to do.
2544 The alternatives are:
2545 1) stop_stepping and return; to really stop and return to the debugger,
2546 2) keep_going and return to start up again
2547 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
2548 3) set ecs->random_signal to 1, and the decision between 1 and 2
2549 will be made according to the signal handling tables. */
2551 /* First, distinguish signals caused by the debugger from signals
2552 that have to do with the program's own actions. Note that
2553 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
2554 on the operating system version. Here we detect when a SIGILL or
2555 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
2556 something similar for SIGSEGV, since a SIGSEGV will be generated
2557 when we're trying to execute a breakpoint instruction on a
2558 non-executable stack. This happens for call dummy breakpoints
2559 for architectures like SPARC that place call dummies on the
2562 If we're doing a displaced step past a breakpoint, then the
2563 breakpoint is always inserted at the original instruction;
2564 non-standard signals can't be explained by the breakpoint. */
2565 if (stop_signal
== TARGET_SIGNAL_TRAP
2566 || (! ecs
->event_thread
->trap_expected
2567 && breakpoint_inserted_here_p (stop_pc
)
2568 && (stop_signal
== TARGET_SIGNAL_ILL
2569 || stop_signal
== TARGET_SIGNAL_SEGV
2570 || stop_signal
== TARGET_SIGNAL_EMT
))
2571 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2572 || stop_soon
== STOP_QUIETLY_REMOTE
)
2574 if (stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
2577 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
2578 stop_print_frame
= 0;
2579 stop_stepping (ecs
);
2583 /* This is originated from start_remote(), start_inferior() and
2584 shared libraries hook functions. */
2585 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
2588 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
2589 stop_stepping (ecs
);
2593 /* This originates from attach_command(). We need to overwrite
2594 the stop_signal here, because some kernels don't ignore a
2595 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
2596 See more comments in inferior.h. On the other hand, if we
2597 get a non-SIGSTOP, report it to the user - assume the backend
2598 will handle the SIGSTOP if it should show up later.
2600 Also consider that the attach is complete when we see a
2601 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
2602 target extended-remote report it instead of a SIGSTOP
2603 (e.g. gdbserver). We already rely on SIGTRAP being our
2604 signal, so this is no exception. */
2605 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2606 && (stop_signal
== TARGET_SIGNAL_STOP
2607 || stop_signal
== TARGET_SIGNAL_TRAP
))
2609 stop_stepping (ecs
);
2610 stop_signal
= TARGET_SIGNAL_0
;
2614 /* See if there is a breakpoint at the current PC. */
2615 stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2617 /* Following in case break condition called a
2619 stop_print_frame
= 1;
2621 /* NOTE: cagney/2003-03-29: These two checks for a random signal
2622 at one stage in the past included checks for an inferior
2623 function call's call dummy's return breakpoint. The original
2624 comment, that went with the test, read:
2626 ``End of a stack dummy. Some systems (e.g. Sony news) give
2627 another signal besides SIGTRAP, so check here as well as
2630 If someone ever tries to get get call dummys on a
2631 non-executable stack to work (where the target would stop
2632 with something like a SIGSEGV), then those tests might need
2633 to be re-instated. Given, however, that the tests were only
2634 enabled when momentary breakpoints were not being used, I
2635 suspect that it won't be the case.
2637 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
2638 be necessary for call dummies on a non-executable stack on
2641 if (stop_signal
== TARGET_SIGNAL_TRAP
)
2643 = !(bpstat_explains_signal (stop_bpstat
)
2644 || ecs
->event_thread
->trap_expected
2645 || (ecs
->event_thread
->step_range_end
2646 && ecs
->event_thread
->step_resume_breakpoint
== NULL
));
2649 ecs
->random_signal
= !bpstat_explains_signal (stop_bpstat
);
2650 if (!ecs
->random_signal
)
2651 stop_signal
= TARGET_SIGNAL_TRAP
;
2655 /* When we reach this point, we've pretty much decided
2656 that the reason for stopping must've been a random
2657 (unexpected) signal. */
2660 ecs
->random_signal
= 1;
2662 process_event_stop_test
:
2663 /* For the program's own signals, act according to
2664 the signal handling tables. */
2666 if (ecs
->random_signal
)
2668 /* Signal not for debugging purposes. */
2672 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n", stop_signal
);
2674 stopped_by_random_signal
= 1;
2676 if (signal_print
[stop_signal
])
2679 target_terminal_ours_for_output ();
2680 print_stop_reason (SIGNAL_RECEIVED
, stop_signal
);
2682 if (signal_stop_state (stop_signal
))
2684 stop_stepping (ecs
);
2687 /* If not going to stop, give terminal back
2688 if we took it away. */
2690 target_terminal_inferior ();
2692 /* Clear the signal if it should not be passed. */
2693 if (signal_program
[stop_signal
] == 0)
2694 stop_signal
= TARGET_SIGNAL_0
;
2696 if (ecs
->event_thread
->prev_pc
== read_pc ()
2697 && ecs
->event_thread
->trap_expected
2698 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
2700 /* We were just starting a new sequence, attempting to
2701 single-step off of a breakpoint and expecting a SIGTRAP.
2702 Instead this signal arrives. This signal will take us out
2703 of the stepping range so GDB needs to remember to, when
2704 the signal handler returns, resume stepping off that
2706 /* To simplify things, "continue" is forced to use the same
2707 code paths as single-step - set a breakpoint at the
2708 signal return address and then, once hit, step off that
2711 fprintf_unfiltered (gdb_stdlog
,
2712 "infrun: signal arrived while stepping over "
2715 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2716 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
2721 if (ecs
->event_thread
->step_range_end
!= 0
2722 && stop_signal
!= TARGET_SIGNAL_0
2723 && (ecs
->event_thread
->step_range_start
<= stop_pc
2724 && stop_pc
< ecs
->event_thread
->step_range_end
)
2725 && frame_id_eq (get_frame_id (get_current_frame ()),
2726 ecs
->event_thread
->step_frame_id
)
2727 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
2729 /* The inferior is about to take a signal that will take it
2730 out of the single step range. Set a breakpoint at the
2731 current PC (which is presumably where the signal handler
2732 will eventually return) and then allow the inferior to
2735 Note that this is only needed for a signal delivered
2736 while in the single-step range. Nested signals aren't a
2737 problem as they eventually all return. */
2739 fprintf_unfiltered (gdb_stdlog
,
2740 "infrun: signal may take us out of "
2741 "single-step range\n");
2743 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2748 /* Note: step_resume_breakpoint may be non-NULL. This occures
2749 when either there's a nested signal, or when there's a
2750 pending signal enabled just as the signal handler returns
2751 (leaving the inferior at the step-resume-breakpoint without
2752 actually executing it). Either way continue until the
2753 breakpoint is really hit. */
2758 /* Handle cases caused by hitting a breakpoint. */
2760 CORE_ADDR jmp_buf_pc
;
2761 struct bpstat_what what
;
2763 what
= bpstat_what (stop_bpstat
);
2765 if (what
.call_dummy
)
2767 stop_stack_dummy
= 1;
2770 switch (what
.main_action
)
2772 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
2773 /* If we hit the breakpoint at longjmp while stepping, we
2774 install a momentary breakpoint at the target of the
2778 fprintf_unfiltered (gdb_stdlog
,
2779 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
2781 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2783 if (!gdbarch_get_longjmp_target_p (current_gdbarch
)
2784 || !gdbarch_get_longjmp_target (current_gdbarch
,
2785 get_current_frame (), &jmp_buf_pc
))
2788 fprintf_unfiltered (gdb_stdlog
, "\
2789 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
2794 /* We're going to replace the current step-resume breakpoint
2795 with a longjmp-resume breakpoint. */
2796 delete_step_resume_breakpoint (ecs
->event_thread
);
2798 /* Insert a breakpoint at resume address. */
2799 insert_longjmp_resume_breakpoint (jmp_buf_pc
);
2804 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
2806 fprintf_unfiltered (gdb_stdlog
,
2807 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
2809 gdb_assert (ecs
->event_thread
->step_resume_breakpoint
!= NULL
);
2810 delete_step_resume_breakpoint (ecs
->event_thread
);
2813 print_stop_reason (END_STEPPING_RANGE
, 0);
2814 stop_stepping (ecs
);
2817 case BPSTAT_WHAT_SINGLE
:
2819 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
2820 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2821 /* Still need to check other stuff, at least the case
2822 where we are stepping and step out of the right range. */
2825 case BPSTAT_WHAT_STOP_NOISY
:
2827 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
2828 stop_print_frame
= 1;
2830 /* We are about to nuke the step_resume_breakpointt via the
2831 cleanup chain, so no need to worry about it here. */
2833 stop_stepping (ecs
);
2836 case BPSTAT_WHAT_STOP_SILENT
:
2838 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
2839 stop_print_frame
= 0;
2841 /* We are about to nuke the step_resume_breakpoin via the
2842 cleanup chain, so no need to worry about it here. */
2844 stop_stepping (ecs
);
2847 case BPSTAT_WHAT_STEP_RESUME
:
2849 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
2851 delete_step_resume_breakpoint (ecs
->event_thread
);
2852 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
2854 /* Back when the step-resume breakpoint was inserted, we
2855 were trying to single-step off a breakpoint. Go back
2857 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
2858 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2864 case BPSTAT_WHAT_CHECK_SHLIBS
:
2865 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
:
2868 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
2870 /* Check for any newly added shared libraries if we're
2871 supposed to be adding them automatically. Switch
2872 terminal for any messages produced by
2873 breakpoint_re_set. */
2874 target_terminal_ours_for_output ();
2875 /* NOTE: cagney/2003-11-25: Make certain that the target
2876 stack's section table is kept up-to-date. Architectures,
2877 (e.g., PPC64), use the section table to perform
2878 operations such as address => section name and hence
2879 require the table to contain all sections (including
2880 those found in shared libraries). */
2881 /* NOTE: cagney/2003-11-25: Pass current_target and not
2882 exec_ops to SOLIB_ADD. This is because current GDB is
2883 only tooled to propagate section_table changes out from
2884 the "current_target" (see target_resize_to_sections), and
2885 not up from the exec stratum. This, of course, isn't
2886 right. "infrun.c" should only interact with the
2887 exec/process stratum, instead relying on the target stack
2888 to propagate relevant changes (stop, section table
2889 changed, ...) up to other layers. */
2891 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2893 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2895 target_terminal_inferior ();
2897 /* If requested, stop when the dynamic linker notifies
2898 gdb of events. This allows the user to get control
2899 and place breakpoints in initializer routines for
2900 dynamically loaded objects (among other things). */
2901 if (stop_on_solib_events
|| stop_stack_dummy
)
2903 stop_stepping (ecs
);
2907 /* If we stopped due to an explicit catchpoint, then the
2908 (see above) call to SOLIB_ADD pulled in any symbols
2909 from a newly-loaded library, if appropriate.
2911 We do want the inferior to stop, but not where it is
2912 now, which is in the dynamic linker callback. Rather,
2913 we would like it stop in the user's program, just after
2914 the call that caused this catchpoint to trigger. That
2915 gives the user a more useful vantage from which to
2916 examine their program's state. */
2917 else if (what
.main_action
2918 == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
)
2920 /* ??rehrauer: If I could figure out how to get the
2921 right return PC from here, we could just set a temp
2922 breakpoint and resume. I'm not sure we can without
2923 cracking open the dld's shared libraries and sniffing
2924 their unwind tables and text/data ranges, and that's
2925 not a terribly portable notion.
2927 Until that time, we must step the inferior out of the
2928 dld callback, and also out of the dld itself (and any
2929 code or stubs in libdld.sl, such as "shl_load" and
2930 friends) until we reach non-dld code. At that point,
2931 we can stop stepping. */
2932 bpstat_get_triggered_catchpoints (stop_bpstat
,
2935 stepping_through_solib_catchpoints
);
2936 ecs
->event_thread
->stepping_through_solib_after_catch
= 1;
2938 /* Be sure to lift all breakpoints, so the inferior does
2939 actually step past this point... */
2940 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2945 /* We want to step over this breakpoint, then keep going. */
2946 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2952 case BPSTAT_WHAT_LAST
:
2953 /* Not a real code, but listed here to shut up gcc -Wall. */
2955 case BPSTAT_WHAT_KEEP_CHECKING
:
2960 /* We come here if we hit a breakpoint but should not
2961 stop for it. Possibly we also were stepping
2962 and should stop for that. So fall through and
2963 test for stepping. But, if not stepping,
2966 /* Are we stepping to get the inferior out of the dynamic linker's
2967 hook (and possibly the dld itself) after catching a shlib
2969 if (ecs
->event_thread
->stepping_through_solib_after_catch
)
2971 #if defined(SOLIB_ADD)
2972 /* Have we reached our destination? If not, keep going. */
2973 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
2976 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
2977 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2983 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
2984 /* Else, stop and report the catchpoint(s) whose triggering
2985 caused us to begin stepping. */
2986 ecs
->event_thread
->stepping_through_solib_after_catch
= 0;
2987 bpstat_clear (&stop_bpstat
);
2988 stop_bpstat
= bpstat_copy (ecs
->event_thread
->stepping_through_solib_catchpoints
);
2989 bpstat_clear (&ecs
->event_thread
->stepping_through_solib_catchpoints
);
2990 stop_print_frame
= 1;
2991 stop_stepping (ecs
);
2995 if (ecs
->event_thread
->step_resume_breakpoint
)
2998 fprintf_unfiltered (gdb_stdlog
,
2999 "infrun: step-resume breakpoint is inserted\n");
3001 /* Having a step-resume breakpoint overrides anything
3002 else having to do with stepping commands until
3003 that breakpoint is reached. */
3008 if (ecs
->event_thread
->step_range_end
== 0)
3011 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
3012 /* Likewise if we aren't even stepping. */
3017 /* If stepping through a line, keep going if still within it.
3019 Note that step_range_end is the address of the first instruction
3020 beyond the step range, and NOT the address of the last instruction
3022 if (stop_pc
>= ecs
->event_thread
->step_range_start
3023 && stop_pc
< ecs
->event_thread
->step_range_end
)
3026 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping inside range [0x%s-0x%s]\n",
3027 paddr_nz (ecs
->event_thread
->step_range_start
),
3028 paddr_nz (ecs
->event_thread
->step_range_end
));
3033 /* We stepped out of the stepping range. */
3035 /* If we are stepping at the source level and entered the runtime
3036 loader dynamic symbol resolution code, we keep on single stepping
3037 until we exit the run time loader code and reach the callee's
3039 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3040 && in_solib_dynsym_resolve_code (stop_pc
))
3042 CORE_ADDR pc_after_resolver
=
3043 gdbarch_skip_solib_resolver (current_gdbarch
, stop_pc
);
3046 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
3048 if (pc_after_resolver
)
3050 /* Set up a step-resume breakpoint at the address
3051 indicated by SKIP_SOLIB_RESOLVER. */
3052 struct symtab_and_line sr_sal
;
3054 sr_sal
.pc
= pc_after_resolver
;
3056 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3063 if (ecs
->event_thread
->step_range_end
!= 1
3064 && (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3065 || ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3066 && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME
)
3069 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
3070 /* The inferior, while doing a "step" or "next", has ended up in
3071 a signal trampoline (either by a signal being delivered or by
3072 the signal handler returning). Just single-step until the
3073 inferior leaves the trampoline (either by calling the handler
3079 /* Check for subroutine calls. The check for the current frame
3080 equalling the step ID is not necessary - the check of the
3081 previous frame's ID is sufficient - but it is a common case and
3082 cheaper than checking the previous frame's ID.
3084 NOTE: frame_id_eq will never report two invalid frame IDs as
3085 being equal, so to get into this block, both the current and
3086 previous frame must have valid frame IDs. */
3087 if (!frame_id_eq (get_frame_id (get_current_frame ()),
3088 ecs
->event_thread
->step_frame_id
)
3089 && frame_id_eq (frame_unwind_id (get_current_frame ()),
3090 ecs
->event_thread
->step_frame_id
))
3092 CORE_ADDR real_stop_pc
;
3095 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
3097 if ((ecs
->event_thread
->step_over_calls
== STEP_OVER_NONE
)
3098 || ((ecs
->event_thread
->step_range_end
== 1)
3099 && in_prologue (ecs
->event_thread
->prev_pc
,
3100 ecs
->stop_func_start
)))
3102 /* I presume that step_over_calls is only 0 when we're
3103 supposed to be stepping at the assembly language level
3104 ("stepi"). Just stop. */
3105 /* Also, maybe we just did a "nexti" inside a prolog, so we
3106 thought it was a subroutine call but it was not. Stop as
3109 print_stop_reason (END_STEPPING_RANGE
, 0);
3110 stop_stepping (ecs
);
3114 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3116 /* We're doing a "next", set a breakpoint at callee's return
3117 address (the address at which the caller will
3119 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3124 /* If we are in a function call trampoline (a stub between the
3125 calling routine and the real function), locate the real
3126 function. That's what tells us (a) whether we want to step
3127 into it at all, and (b) what prologue we want to run to the
3128 end of, if we do step into it. */
3129 real_stop_pc
= skip_language_trampoline (get_current_frame (), stop_pc
);
3130 if (real_stop_pc
== 0)
3131 real_stop_pc
= gdbarch_skip_trampoline_code
3132 (current_gdbarch
, get_current_frame (), stop_pc
);
3133 if (real_stop_pc
!= 0)
3134 ecs
->stop_func_start
= real_stop_pc
;
3136 if (in_solib_dynsym_resolve_code (ecs
->stop_func_start
))
3138 struct symtab_and_line sr_sal
;
3140 sr_sal
.pc
= ecs
->stop_func_start
;
3142 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3147 /* If we have line number information for the function we are
3148 thinking of stepping into, step into it.
3150 If there are several symtabs at that PC (e.g. with include
3151 files), just want to know whether *any* of them have line
3152 numbers. find_pc_line handles this. */
3154 struct symtab_and_line tmp_sal
;
3156 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3157 if (tmp_sal
.line
!= 0)
3159 step_into_function (ecs
);
3164 /* If we have no line number and the step-stop-if-no-debug is
3165 set, we stop the step so that the user has a chance to switch
3166 in assembly mode. */
3167 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3168 && step_stop_if_no_debug
)
3171 print_stop_reason (END_STEPPING_RANGE
, 0);
3172 stop_stepping (ecs
);
3176 /* Set a breakpoint at callee's return address (the address at
3177 which the caller will resume). */
3178 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3183 /* If we're in the return path from a shared library trampoline,
3184 we want to proceed through the trampoline when stepping. */
3185 if (gdbarch_in_solib_return_trampoline (current_gdbarch
,
3186 stop_pc
, ecs
->stop_func_name
))
3188 /* Determine where this trampoline returns. */
3189 CORE_ADDR real_stop_pc
;
3190 real_stop_pc
= gdbarch_skip_trampoline_code
3191 (current_gdbarch
, get_current_frame (), stop_pc
);
3194 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
3196 /* Only proceed through if we know where it's going. */
3199 /* And put the step-breakpoint there and go until there. */
3200 struct symtab_and_line sr_sal
;
3202 init_sal (&sr_sal
); /* initialize to zeroes */
3203 sr_sal
.pc
= real_stop_pc
;
3204 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3206 /* Do not specify what the fp should be when we stop since
3207 on some machines the prologue is where the new fp value
3209 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3211 /* Restart without fiddling with the step ranges or
3218 stop_pc_sal
= find_pc_line (stop_pc
, 0);
3220 /* NOTE: tausq/2004-05-24: This if block used to be done before all
3221 the trampoline processing logic, however, there are some trampolines
3222 that have no names, so we should do trampoline handling first. */
3223 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3224 && ecs
->stop_func_name
== NULL
3225 && stop_pc_sal
.line
== 0)
3228 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
3230 /* The inferior just stepped into, or returned to, an
3231 undebuggable function (where there is no debugging information
3232 and no line number corresponding to the address where the
3233 inferior stopped). Since we want to skip this kind of code,
3234 we keep going until the inferior returns from this
3235 function - unless the user has asked us not to (via
3236 set step-mode) or we no longer know how to get back
3237 to the call site. */
3238 if (step_stop_if_no_debug
3239 || !frame_id_p (frame_unwind_id (get_current_frame ())))
3241 /* If we have no line number and the step-stop-if-no-debug
3242 is set, we stop the step so that the user has a chance to
3243 switch in assembly mode. */
3245 print_stop_reason (END_STEPPING_RANGE
, 0);
3246 stop_stepping (ecs
);
3251 /* Set a breakpoint at callee's return address (the address
3252 at which the caller will resume). */
3253 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3259 if (ecs
->event_thread
->step_range_end
== 1)
3261 /* It is stepi or nexti. We always want to stop stepping after
3264 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
3266 print_stop_reason (END_STEPPING_RANGE
, 0);
3267 stop_stepping (ecs
);
3271 if (stop_pc_sal
.line
== 0)
3273 /* We have no line number information. That means to stop
3274 stepping (does this always happen right after one instruction,
3275 when we do "s" in a function with no line numbers,
3276 or can this happen as a result of a return or longjmp?). */
3278 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
3280 print_stop_reason (END_STEPPING_RANGE
, 0);
3281 stop_stepping (ecs
);
3285 if ((stop_pc
== stop_pc_sal
.pc
)
3286 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
3287 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
3289 /* We are at the start of a different line. So stop. Note that
3290 we don't stop if we step into the middle of a different line.
3291 That is said to make things like for (;;) statements work
3294 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
3296 print_stop_reason (END_STEPPING_RANGE
, 0);
3297 stop_stepping (ecs
);
3301 /* We aren't done stepping.
3303 Optimize by setting the stepping range to the line.
3304 (We might not be in the original line, but if we entered a
3305 new line in mid-statement, we continue stepping. This makes
3306 things like for(;;) statements work better.) */
3308 ecs
->event_thread
->step_range_start
= stop_pc_sal
.pc
;
3309 ecs
->event_thread
->step_range_end
= stop_pc_sal
.end
;
3310 ecs
->event_thread
->step_frame_id
= get_frame_id (get_current_frame ());
3311 ecs
->event_thread
->current_line
= stop_pc_sal
.line
;
3312 ecs
->event_thread
->current_symtab
= stop_pc_sal
.symtab
;
3315 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
3319 /* Are we in the middle of stepping? */
3322 currently_stepping (struct thread_info
*tp
)
3324 return (((tp
->step_range_end
&& tp
->step_resume_breakpoint
== NULL
)
3325 || tp
->trap_expected
)
3326 || tp
->stepping_through_solib_after_catch
3327 || bpstat_should_step ());
3330 /* Subroutine call with source code we should not step over. Do step
3331 to the first line of code in it. */
3334 step_into_function (struct execution_control_state
*ecs
)
3337 struct symtab_and_line stop_func_sal
, sr_sal
;
3339 s
= find_pc_symtab (stop_pc
);
3340 if (s
&& s
->language
!= language_asm
)
3341 ecs
->stop_func_start
= gdbarch_skip_prologue
3342 (current_gdbarch
, ecs
->stop_func_start
);
3344 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3345 /* Use the step_resume_break to step until the end of the prologue,
3346 even if that involves jumps (as it seems to on the vax under
3348 /* If the prologue ends in the middle of a source line, continue to
3349 the end of that source line (if it is still within the function).
3350 Otherwise, just go to end of prologue. */
3351 if (stop_func_sal
.end
3352 && stop_func_sal
.pc
!= ecs
->stop_func_start
3353 && stop_func_sal
.end
< ecs
->stop_func_end
)
3354 ecs
->stop_func_start
= stop_func_sal
.end
;
3356 /* Architectures which require breakpoint adjustment might not be able
3357 to place a breakpoint at the computed address. If so, the test
3358 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
3359 ecs->stop_func_start to an address at which a breakpoint may be
3360 legitimately placed.
3362 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
3363 made, GDB will enter an infinite loop when stepping through
3364 optimized code consisting of VLIW instructions which contain
3365 subinstructions corresponding to different source lines. On
3366 FR-V, it's not permitted to place a breakpoint on any but the
3367 first subinstruction of a VLIW instruction. When a breakpoint is
3368 set, GDB will adjust the breakpoint address to the beginning of
3369 the VLIW instruction. Thus, we need to make the corresponding
3370 adjustment here when computing the stop address. */
3372 if (gdbarch_adjust_breakpoint_address_p (current_gdbarch
))
3374 ecs
->stop_func_start
3375 = gdbarch_adjust_breakpoint_address (current_gdbarch
,
3376 ecs
->stop_func_start
);
3379 if (ecs
->stop_func_start
== stop_pc
)
3381 /* We are already there: stop now. */
3383 print_stop_reason (END_STEPPING_RANGE
, 0);
3384 stop_stepping (ecs
);
3389 /* Put the step-breakpoint there and go until there. */
3390 init_sal (&sr_sal
); /* initialize to zeroes */
3391 sr_sal
.pc
= ecs
->stop_func_start
;
3392 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
3394 /* Do not specify what the fp should be when we stop since on
3395 some machines the prologue is where the new fp value is
3397 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3399 /* And make sure stepping stops right away then. */
3400 ecs
->event_thread
->step_range_end
= ecs
->event_thread
->step_range_start
;
3405 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
3406 This is used to both functions and to skip over code. */
3409 insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
3410 struct frame_id sr_id
)
3412 /* There should never be more than one step-resume or longjmp-resume
3413 breakpoint per thread, so we should never be setting a new
3414 step_resume_breakpoint when one is already active. */
3415 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
3418 fprintf_unfiltered (gdb_stdlog
,
3419 "infrun: inserting step-resume breakpoint at 0x%s\n",
3420 paddr_nz (sr_sal
.pc
));
3422 inferior_thread ()->step_resume_breakpoint
3423 = set_momentary_breakpoint (sr_sal
, sr_id
, bp_step_resume
);
3426 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
3427 to skip a potential signal handler.
3429 This is called with the interrupted function's frame. The signal
3430 handler, when it returns, will resume the interrupted function at
3434 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
3436 struct symtab_and_line sr_sal
;
3438 gdb_assert (return_frame
!= NULL
);
3439 init_sal (&sr_sal
); /* initialize to zeros */
3441 sr_sal
.pc
= gdbarch_addr_bits_remove
3442 (current_gdbarch
, get_frame_pc (return_frame
));
3443 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3445 insert_step_resume_breakpoint_at_sal (sr_sal
, get_frame_id (return_frame
));
3448 /* Similar to insert_step_resume_breakpoint_at_frame, except
3449 but a breakpoint at the previous frame's PC. This is used to
3450 skip a function after stepping into it (for "next" or if the called
3451 function has no debugging information).
3453 The current function has almost always been reached by single
3454 stepping a call or return instruction. NEXT_FRAME belongs to the
3455 current function, and the breakpoint will be set at the caller's
3458 This is a separate function rather than reusing
3459 insert_step_resume_breakpoint_at_frame in order to avoid
3460 get_prev_frame, which may stop prematurely (see the implementation
3461 of frame_unwind_id for an example). */
3464 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
3466 struct symtab_and_line sr_sal
;
3468 /* We shouldn't have gotten here if we don't know where the call site
3470 gdb_assert (frame_id_p (frame_unwind_id (next_frame
)));
3472 init_sal (&sr_sal
); /* initialize to zeros */
3474 sr_sal
.pc
= gdbarch_addr_bits_remove
3475 (current_gdbarch
, frame_pc_unwind (next_frame
));
3476 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3478 insert_step_resume_breakpoint_at_sal (sr_sal
, frame_unwind_id (next_frame
));
3481 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
3482 new breakpoint at the target of a jmp_buf. The handling of
3483 longjmp-resume uses the same mechanisms used for handling
3484 "step-resume" breakpoints. */
3487 insert_longjmp_resume_breakpoint (CORE_ADDR pc
)
3489 /* There should never be more than one step-resume or longjmp-resume
3490 breakpoint per thread, so we should never be setting a new
3491 longjmp_resume_breakpoint when one is already active. */
3492 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
3495 fprintf_unfiltered (gdb_stdlog
,
3496 "infrun: inserting longjmp-resume breakpoint at 0x%s\n",
3499 inferior_thread ()->step_resume_breakpoint
=
3500 set_momentary_breakpoint_at_pc (pc
, bp_longjmp_resume
);
3504 stop_stepping (struct execution_control_state
*ecs
)
3507 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
3509 /* Let callers know we don't want to wait for the inferior anymore. */
3510 ecs
->wait_some_more
= 0;
3513 /* This function handles various cases where we need to continue
3514 waiting for the inferior. */
3515 /* (Used to be the keep_going: label in the old wait_for_inferior) */
3518 keep_going (struct execution_control_state
*ecs
)
3520 /* Save the pc before execution, to compare with pc after stop. */
3521 ecs
->event_thread
->prev_pc
= read_pc (); /* Might have been DECR_AFTER_BREAK */
3523 /* If we did not do break;, it means we should keep running the
3524 inferior and not return to debugger. */
3526 if (ecs
->event_thread
->trap_expected
&& stop_signal
!= TARGET_SIGNAL_TRAP
)
3528 /* We took a signal (which we are supposed to pass through to
3529 the inferior, else we'd not get here) and we haven't yet
3530 gotten our trap. Simply continue. */
3531 resume (currently_stepping (ecs
->event_thread
), stop_signal
);
3535 /* Either the trap was not expected, but we are continuing
3536 anyway (the user asked that this signal be passed to the
3539 The signal was SIGTRAP, e.g. it was our signal, but we
3540 decided we should resume from it.
3542 We're going to run this baby now!
3544 Note that insert_breakpoints won't try to re-insert
3545 already inserted breakpoints. Therefore, we don't
3546 care if breakpoints were already inserted, or not. */
3548 if (ecs
->event_thread
->stepping_over_breakpoint
)
3550 if (! use_displaced_stepping (current_gdbarch
))
3551 /* Since we can't do a displaced step, we have to remove
3552 the breakpoint while we step it. To keep things
3553 simple, we remove them all. */
3554 remove_breakpoints ();
3558 struct gdb_exception e
;
3559 /* Stop stepping when inserting breakpoints
3561 TRY_CATCH (e
, RETURN_MASK_ERROR
)
3563 insert_breakpoints ();
3567 stop_stepping (ecs
);
3572 ecs
->event_thread
->trap_expected
= ecs
->event_thread
->stepping_over_breakpoint
;
3574 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3575 specifies that such a signal should be delivered to the
3578 Typically, this would occure when a user is debugging a
3579 target monitor on a simulator: the target monitor sets a
3580 breakpoint; the simulator encounters this break-point and
3581 halts the simulation handing control to GDB; GDB, noteing
3582 that the break-point isn't valid, returns control back to the
3583 simulator; the simulator then delivers the hardware
3584 equivalent of a SIGNAL_TRAP to the program being debugged. */
3586 if (stop_signal
== TARGET_SIGNAL_TRAP
&& !signal_program
[stop_signal
])
3587 stop_signal
= TARGET_SIGNAL_0
;
3590 resume (currently_stepping (ecs
->event_thread
), stop_signal
);
3593 prepare_to_wait (ecs
);
3596 /* This function normally comes after a resume, before
3597 handle_inferior_event exits. It takes care of any last bits of
3598 housekeeping, and sets the all-important wait_some_more flag. */
3601 prepare_to_wait (struct execution_control_state
*ecs
)
3604 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
3605 if (infwait_state
== infwait_normal_state
)
3607 overlay_cache_invalid
= 1;
3609 /* We have to invalidate the registers BEFORE calling
3610 target_wait because they can be loaded from the target while
3611 in target_wait. This makes remote debugging a bit more
3612 efficient for those targets that provide critical registers
3613 as part of their normal status mechanism. */
3615 registers_changed ();
3616 waiton_ptid
= pid_to_ptid (-1);
3618 /* This is the old end of the while loop. Let everybody know we
3619 want to wait for the inferior some more and get called again
3621 ecs
->wait_some_more
= 1;
3624 /* Print why the inferior has stopped. We always print something when
3625 the inferior exits, or receives a signal. The rest of the cases are
3626 dealt with later on in normal_stop() and print_it_typical(). Ideally
3627 there should be a call to this function from handle_inferior_event()
3628 each time stop_stepping() is called.*/
3630 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
3632 switch (stop_reason
)
3634 case END_STEPPING_RANGE
:
3635 /* We are done with a step/next/si/ni command. */
3636 /* For now print nothing. */
3637 /* Print a message only if not in the middle of doing a "step n"
3638 operation for n > 1 */
3639 if (!step_multi
|| !stop_step
)
3640 if (ui_out_is_mi_like_p (uiout
))
3643 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
3646 /* The inferior was terminated by a signal. */
3647 annotate_signalled ();
3648 if (ui_out_is_mi_like_p (uiout
))
3651 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
3652 ui_out_text (uiout
, "\nProgram terminated with signal ");
3653 annotate_signal_name ();
3654 ui_out_field_string (uiout
, "signal-name",
3655 target_signal_to_name (stop_info
));
3656 annotate_signal_name_end ();
3657 ui_out_text (uiout
, ", ");
3658 annotate_signal_string ();
3659 ui_out_field_string (uiout
, "signal-meaning",
3660 target_signal_to_string (stop_info
));
3661 annotate_signal_string_end ();
3662 ui_out_text (uiout
, ".\n");
3663 ui_out_text (uiout
, "The program no longer exists.\n");
3666 /* The inferior program is finished. */
3667 annotate_exited (stop_info
);
3670 if (ui_out_is_mi_like_p (uiout
))
3671 ui_out_field_string (uiout
, "reason",
3672 async_reason_lookup (EXEC_ASYNC_EXITED
));
3673 ui_out_text (uiout
, "\nProgram exited with code ");
3674 ui_out_field_fmt (uiout
, "exit-code", "0%o",
3675 (unsigned int) stop_info
);
3676 ui_out_text (uiout
, ".\n");
3680 if (ui_out_is_mi_like_p (uiout
))
3683 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
3684 ui_out_text (uiout
, "\nProgram exited normally.\n");
3686 /* Support the --return-child-result option. */
3687 return_child_result_value
= stop_info
;
3689 case SIGNAL_RECEIVED
:
3690 /* Signal received. The signal table tells us to print about
3693 ui_out_text (uiout
, "\nProgram received signal ");
3694 annotate_signal_name ();
3695 if (ui_out_is_mi_like_p (uiout
))
3697 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
3698 ui_out_field_string (uiout
, "signal-name",
3699 target_signal_to_name (stop_info
));
3700 annotate_signal_name_end ();
3701 ui_out_text (uiout
, ", ");
3702 annotate_signal_string ();
3703 ui_out_field_string (uiout
, "signal-meaning",
3704 target_signal_to_string (stop_info
));
3705 annotate_signal_string_end ();
3706 ui_out_text (uiout
, ".\n");
3709 internal_error (__FILE__
, __LINE__
,
3710 _("print_stop_reason: unrecognized enum value"));
3716 /* Here to return control to GDB when the inferior stops for real.
3717 Print appropriate messages, remove breakpoints, give terminal our modes.
3719 STOP_PRINT_FRAME nonzero means print the executing frame
3720 (pc, function, args, file, line number and line text).
3721 BREAKPOINTS_FAILED nonzero means stop was due to error
3722 attempting to insert breakpoints. */
3727 struct target_waitstatus last
;
3730 get_last_target_status (&last_ptid
, &last
);
3732 /* In non-stop mode, we don't want GDB to switch threads behind the
3733 user's back, to avoid races where the user is typing a command to
3734 apply to thread x, but GDB switches to thread y before the user
3735 finishes entering the command. */
3737 /* As with the notification of thread events, we want to delay
3738 notifying the user that we've switched thread context until
3739 the inferior actually stops.
3741 There's no point in saying anything if the inferior has exited.
3742 Note that SIGNALLED here means "exited with a signal", not
3743 "received a signal". */
3745 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
3746 && target_has_execution
3747 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3748 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3750 target_terminal_ours_for_output ();
3751 printf_filtered (_("[Switching to %s]\n"),
3752 target_pid_to_str (inferior_ptid
));
3753 annotate_thread_changed ();
3754 previous_inferior_ptid
= inferior_ptid
;
3757 /* NOTE drow/2004-01-17: Is this still necessary? */
3758 /* Make sure that the current_frame's pc is correct. This
3759 is a correction for setting up the frame info before doing
3760 gdbarch_decr_pc_after_break */
3761 if (target_has_execution
)
3762 /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
3763 gdbarch_decr_pc_after_break, the program counter can change. Ask the
3764 frame code to check for this and sort out any resultant mess.
3765 gdbarch_decr_pc_after_break needs to just go away. */
3766 deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
3768 if (!breakpoints_always_inserted_mode () && target_has_execution
)
3770 if (remove_breakpoints ())
3772 target_terminal_ours_for_output ();
3773 printf_filtered (_("\
3774 Cannot remove breakpoints because program is no longer writable.\n\
3775 It might be running in another process.\n\
3776 Further execution is probably impossible.\n"));
3780 /* If an auto-display called a function and that got a signal,
3781 delete that auto-display to avoid an infinite recursion. */
3783 if (stopped_by_random_signal
)
3784 disable_current_display ();
3786 /* Don't print a message if in the middle of doing a "step n"
3787 operation for n > 1 */
3788 if (step_multi
&& stop_step
)
3791 target_terminal_ours ();
3793 /* Set the current source location. This will also happen if we
3794 display the frame below, but the current SAL will be incorrect
3795 during a user hook-stop function. */
3796 if (target_has_stack
&& !stop_stack_dummy
)
3797 set_current_sal_from_frame (get_current_frame (), 1);
3799 /* Look up the hook_stop and run it (CLI internally handles problem
3800 of stop_command's pre-hook not existing). */
3802 catch_errors (hook_stop_stub
, stop_command
,
3803 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
3805 if (!target_has_stack
)
3811 /* Select innermost stack frame - i.e., current frame is frame 0,
3812 and current location is based on that.
3813 Don't do this on return from a stack dummy routine,
3814 or if the program has exited. */
3816 if (!stop_stack_dummy
)
3818 select_frame (get_current_frame ());
3820 /* Print current location without a level number, if
3821 we have changed functions or hit a breakpoint.
3822 Print source line if we have one.
3823 bpstat_print() contains the logic deciding in detail
3824 what to print, based on the event(s) that just occurred. */
3826 /* If --batch-silent is enabled then there's no need to print the current
3827 source location, and to try risks causing an error message about
3828 missing source files. */
3829 if (stop_print_frame
&& !batch_silent
)
3833 int do_frame_printing
= 1;
3835 bpstat_ret
= bpstat_print (stop_bpstat
);
3839 /* If we had hit a shared library event breakpoint,
3840 bpstat_print would print out this message. If we hit
3841 an OS-level shared library event, do the same
3843 if (last
.kind
== TARGET_WAITKIND_LOADED
)
3845 printf_filtered (_("Stopped due to shared library event\n"));
3846 source_flag
= SRC_LINE
; /* something bogus */
3847 do_frame_printing
= 0;
3851 /* FIXME: cagney/2002-12-01: Given that a frame ID does
3852 (or should) carry around the function and does (or
3853 should) use that when doing a frame comparison. */
3855 && frame_id_eq (inferior_thread ()->step_frame_id
,
3856 get_frame_id (get_current_frame ()))
3857 && step_start_function
== find_pc_function (stop_pc
))
3858 source_flag
= SRC_LINE
; /* finished step, just print source line */
3860 source_flag
= SRC_AND_LOC
; /* print location and source line */
3862 case PRINT_SRC_AND_LOC
:
3863 source_flag
= SRC_AND_LOC
; /* print location and source line */
3865 case PRINT_SRC_ONLY
:
3866 source_flag
= SRC_LINE
;
3869 source_flag
= SRC_LINE
; /* something bogus */
3870 do_frame_printing
= 0;
3873 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
3876 if (ui_out_is_mi_like_p (uiout
))
3879 ui_out_field_int (uiout
, "thread-id",
3880 pid_to_thread_id (inferior_ptid
));
3883 struct cleanup
*back_to
= make_cleanup_ui_out_list_begin_end
3884 (uiout
, "stopped-threads");
3885 ui_out_field_int (uiout
, NULL
,
3886 pid_to_thread_id (inferior_ptid
));
3887 do_cleanups (back_to
);
3890 ui_out_field_string (uiout
, "stopped-threads", "all");
3892 /* The behavior of this routine with respect to the source
3894 SRC_LINE: Print only source line
3895 LOCATION: Print only location
3896 SRC_AND_LOC: Print location and source line */
3897 if (do_frame_printing
)
3898 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
3900 /* Display the auto-display expressions. */
3905 /* Save the function value return registers, if we care.
3906 We might be about to restore their previous contents. */
3907 if (proceed_to_finish
)
3909 /* This should not be necessary. */
3911 regcache_xfree (stop_registers
);
3913 /* NB: The copy goes through to the target picking up the value of
3914 all the registers. */
3915 stop_registers
= regcache_dup (get_current_regcache ());
3918 if (stop_stack_dummy
)
3920 /* Pop the empty frame that contains the stack dummy. POP_FRAME
3921 ends with a setting of the current frame, so we can use that
3923 frame_pop (get_current_frame ());
3924 /* Set stop_pc to what it was before we called the function.
3925 Can't rely on restore_inferior_status because that only gets
3926 called if we don't stop in the called function. */
3927 stop_pc
= read_pc ();
3928 select_frame (get_current_frame ());
3932 annotate_stopped ();
3933 if (!suppress_stop_observer
&& !step_multi
)
3934 observer_notify_normal_stop (stop_bpstat
);
3935 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3936 Delete any breakpoint that is to be deleted at the next stop. */
3937 breakpoint_auto_delete (stop_bpstat
);
3939 if (target_has_execution
3940 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3941 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3944 set_running (pid_to_ptid (-1), 0);
3946 set_running (inferior_ptid
, 0);
3951 hook_stop_stub (void *cmd
)
3953 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
3958 signal_stop_state (int signo
)
3960 /* Always stop on signals if we're just gaining control of the
3962 return signal_stop
[signo
] || stop_soon
!= NO_STOP_QUIETLY
;
3966 signal_print_state (int signo
)
3968 return signal_print
[signo
];
3972 signal_pass_state (int signo
)
3974 return signal_program
[signo
];
3978 signal_stop_update (int signo
, int state
)
3980 int ret
= signal_stop
[signo
];
3981 signal_stop
[signo
] = state
;
3986 signal_print_update (int signo
, int state
)
3988 int ret
= signal_print
[signo
];
3989 signal_print
[signo
] = state
;
3994 signal_pass_update (int signo
, int state
)
3996 int ret
= signal_program
[signo
];
3997 signal_program
[signo
] = state
;
4002 sig_print_header (void)
4004 printf_filtered (_("\
4005 Signal Stop\tPrint\tPass to program\tDescription\n"));
4009 sig_print_info (enum target_signal oursig
)
4011 char *name
= target_signal_to_name (oursig
);
4012 int name_padding
= 13 - strlen (name
);
4014 if (name_padding
<= 0)
4017 printf_filtered ("%s", name
);
4018 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
4019 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
4020 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
4021 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
4022 printf_filtered ("%s\n", target_signal_to_string (oursig
));
4025 /* Specify how various signals in the inferior should be handled. */
4028 handle_command (char *args
, int from_tty
)
4031 int digits
, wordlen
;
4032 int sigfirst
, signum
, siglast
;
4033 enum target_signal oursig
;
4036 unsigned char *sigs
;
4037 struct cleanup
*old_chain
;
4041 error_no_arg (_("signal to handle"));
4044 /* Allocate and zero an array of flags for which signals to handle. */
4046 nsigs
= (int) TARGET_SIGNAL_LAST
;
4047 sigs
= (unsigned char *) alloca (nsigs
);
4048 memset (sigs
, 0, nsigs
);
4050 /* Break the command line up into args. */
4052 argv
= buildargv (args
);
4057 old_chain
= make_cleanup_freeargv (argv
);
4059 /* Walk through the args, looking for signal oursigs, signal names, and
4060 actions. Signal numbers and signal names may be interspersed with
4061 actions, with the actions being performed for all signals cumulatively
4062 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
4064 while (*argv
!= NULL
)
4066 wordlen
= strlen (*argv
);
4067 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
4071 sigfirst
= siglast
= -1;
4073 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
4075 /* Apply action to all signals except those used by the
4076 debugger. Silently skip those. */
4079 siglast
= nsigs
- 1;
4081 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
4083 SET_SIGS (nsigs
, sigs
, signal_stop
);
4084 SET_SIGS (nsigs
, sigs
, signal_print
);
4086 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
4088 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4090 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
4092 SET_SIGS (nsigs
, sigs
, signal_print
);
4094 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
4096 SET_SIGS (nsigs
, sigs
, signal_program
);
4098 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
4100 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4102 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
4104 SET_SIGS (nsigs
, sigs
, signal_program
);
4106 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
4108 UNSET_SIGS (nsigs
, sigs
, signal_print
);
4109 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4111 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
4113 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4115 else if (digits
> 0)
4117 /* It is numeric. The numeric signal refers to our own
4118 internal signal numbering from target.h, not to host/target
4119 signal number. This is a feature; users really should be
4120 using symbolic names anyway, and the common ones like
4121 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
4123 sigfirst
= siglast
= (int)
4124 target_signal_from_command (atoi (*argv
));
4125 if ((*argv
)[digits
] == '-')
4128 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
4130 if (sigfirst
> siglast
)
4132 /* Bet he didn't figure we'd think of this case... */
4140 oursig
= target_signal_from_name (*argv
);
4141 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
4143 sigfirst
= siglast
= (int) oursig
;
4147 /* Not a number and not a recognized flag word => complain. */
4148 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
4152 /* If any signal numbers or symbol names were found, set flags for
4153 which signals to apply actions to. */
4155 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
4157 switch ((enum target_signal
) signum
)
4159 case TARGET_SIGNAL_TRAP
:
4160 case TARGET_SIGNAL_INT
:
4161 if (!allsigs
&& !sigs
[signum
])
4163 if (query ("%s is used by the debugger.\n\
4164 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal
) signum
)))
4170 printf_unfiltered (_("Not confirmed, unchanged.\n"));
4171 gdb_flush (gdb_stdout
);
4175 case TARGET_SIGNAL_0
:
4176 case TARGET_SIGNAL_DEFAULT
:
4177 case TARGET_SIGNAL_UNKNOWN
:
4178 /* Make sure that "all" doesn't print these. */
4189 target_notice_signals (inferior_ptid
);
4193 /* Show the results. */
4194 sig_print_header ();
4195 for (signum
= 0; signum
< nsigs
; signum
++)
4199 sig_print_info (signum
);
4204 do_cleanups (old_chain
);
4208 xdb_handle_command (char *args
, int from_tty
)
4211 struct cleanup
*old_chain
;
4213 /* Break the command line up into args. */
4215 argv
= buildargv (args
);
4220 old_chain
= make_cleanup_freeargv (argv
);
4221 if (argv
[1] != (char *) NULL
)
4226 bufLen
= strlen (argv
[0]) + 20;
4227 argBuf
= (char *) xmalloc (bufLen
);
4231 enum target_signal oursig
;
4233 oursig
= target_signal_from_name (argv
[0]);
4234 memset (argBuf
, 0, bufLen
);
4235 if (strcmp (argv
[1], "Q") == 0)
4236 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4239 if (strcmp (argv
[1], "s") == 0)
4241 if (!signal_stop
[oursig
])
4242 sprintf (argBuf
, "%s %s", argv
[0], "stop");
4244 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
4246 else if (strcmp (argv
[1], "i") == 0)
4248 if (!signal_program
[oursig
])
4249 sprintf (argBuf
, "%s %s", argv
[0], "pass");
4251 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
4253 else if (strcmp (argv
[1], "r") == 0)
4255 if (!signal_print
[oursig
])
4256 sprintf (argBuf
, "%s %s", argv
[0], "print");
4258 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4264 handle_command (argBuf
, from_tty
);
4266 printf_filtered (_("Invalid signal handling flag.\n"));
4271 do_cleanups (old_chain
);
4274 /* Print current contents of the tables set by the handle command.
4275 It is possible we should just be printing signals actually used
4276 by the current target (but for things to work right when switching
4277 targets, all signals should be in the signal tables). */
4280 signals_info (char *signum_exp
, int from_tty
)
4282 enum target_signal oursig
;
4283 sig_print_header ();
4287 /* First see if this is a symbol name. */
4288 oursig
= target_signal_from_name (signum_exp
);
4289 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
4291 /* No, try numeric. */
4293 target_signal_from_command (parse_and_eval_long (signum_exp
));
4295 sig_print_info (oursig
);
4299 printf_filtered ("\n");
4300 /* These ugly casts brought to you by the native VAX compiler. */
4301 for (oursig
= TARGET_SIGNAL_FIRST
;
4302 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
4303 oursig
= (enum target_signal
) ((int) oursig
+ 1))
4307 if (oursig
!= TARGET_SIGNAL_UNKNOWN
4308 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
4309 sig_print_info (oursig
);
4312 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
4315 struct inferior_status
4317 enum target_signal stop_signal
;
4321 int stop_stack_dummy
;
4322 int stopped_by_random_signal
;
4323 int stepping_over_breakpoint
;
4324 CORE_ADDR step_range_start
;
4325 CORE_ADDR step_range_end
;
4326 struct frame_id step_frame_id
;
4327 enum step_over_calls_kind step_over_calls
;
4328 CORE_ADDR step_resume_break_address
;
4329 int stop_after_trap
;
4332 /* These are here because if call_function_by_hand has written some
4333 registers and then decides to call error(), we better not have changed
4335 struct regcache
*registers
;
4337 /* A frame unique identifier. */
4338 struct frame_id selected_frame_id
;
4340 int breakpoint_proceeded
;
4341 int restore_stack_info
;
4342 int proceed_to_finish
;
4346 write_inferior_status_register (struct inferior_status
*inf_status
, int regno
,
4349 int size
= register_size (current_gdbarch
, regno
);
4350 void *buf
= alloca (size
);
4351 store_signed_integer (buf
, size
, val
);
4352 regcache_raw_write (inf_status
->registers
, regno
, buf
);
4355 /* Save all of the information associated with the inferior<==>gdb
4356 connection. INF_STATUS is a pointer to a "struct inferior_status"
4357 (defined in inferior.h). */
4359 struct inferior_status
*
4360 save_inferior_status (int restore_stack_info
)
4362 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
4363 struct thread_info
*tp
= inferior_thread ();
4365 inf_status
->stop_signal
= stop_signal
;
4366 inf_status
->stop_pc
= stop_pc
;
4367 inf_status
->stop_step
= stop_step
;
4368 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
4369 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
4370 inf_status
->stepping_over_breakpoint
= tp
->trap_expected
;
4371 inf_status
->step_range_start
= tp
->step_range_start
;
4372 inf_status
->step_range_end
= tp
->step_range_end
;
4373 inf_status
->step_frame_id
= tp
->step_frame_id
;
4374 inf_status
->step_over_calls
= tp
->step_over_calls
;
4375 inf_status
->stop_after_trap
= stop_after_trap
;
4376 inf_status
->stop_soon
= stop_soon
;
4377 /* Save original bpstat chain here; replace it with copy of chain.
4378 If caller's caller is walking the chain, they'll be happier if we
4379 hand them back the original chain when restore_inferior_status is
4381 inf_status
->stop_bpstat
= stop_bpstat
;
4382 stop_bpstat
= bpstat_copy (stop_bpstat
);
4383 inf_status
->breakpoint_proceeded
= breakpoint_proceeded
;
4384 inf_status
->restore_stack_info
= restore_stack_info
;
4385 inf_status
->proceed_to_finish
= proceed_to_finish
;
4387 inf_status
->registers
= regcache_dup (get_current_regcache ());
4389 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
4394 restore_selected_frame (void *args
)
4396 struct frame_id
*fid
= (struct frame_id
*) args
;
4397 struct frame_info
*frame
;
4399 frame
= frame_find_by_id (*fid
);
4401 /* If inf_status->selected_frame_id is NULL, there was no previously
4405 warning (_("Unable to restore previously selected frame."));
4409 select_frame (frame
);
4415 restore_inferior_status (struct inferior_status
*inf_status
)
4417 struct thread_info
*tp
= inferior_thread ();
4419 stop_signal
= inf_status
->stop_signal
;
4420 stop_pc
= inf_status
->stop_pc
;
4421 stop_step
= inf_status
->stop_step
;
4422 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
4423 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
4424 tp
->trap_expected
= inf_status
->stepping_over_breakpoint
;
4425 tp
->step_range_start
= inf_status
->step_range_start
;
4426 tp
->step_range_end
= inf_status
->step_range_end
;
4427 tp
->step_frame_id
= inf_status
->step_frame_id
;
4428 tp
->step_over_calls
= inf_status
->step_over_calls
;
4429 stop_after_trap
= inf_status
->stop_after_trap
;
4430 stop_soon
= inf_status
->stop_soon
;
4431 bpstat_clear (&stop_bpstat
);
4432 stop_bpstat
= inf_status
->stop_bpstat
;
4433 breakpoint_proceeded
= inf_status
->breakpoint_proceeded
;
4434 proceed_to_finish
= inf_status
->proceed_to_finish
;
4436 /* The inferior can be gone if the user types "print exit(0)"
4437 (and perhaps other times). */
4438 if (target_has_execution
)
4439 /* NB: The register write goes through to the target. */
4440 regcache_cpy (get_current_regcache (), inf_status
->registers
);
4441 regcache_xfree (inf_status
->registers
);
4443 /* FIXME: If we are being called after stopping in a function which
4444 is called from gdb, we should not be trying to restore the
4445 selected frame; it just prints a spurious error message (The
4446 message is useful, however, in detecting bugs in gdb (like if gdb
4447 clobbers the stack)). In fact, should we be restoring the
4448 inferior status at all in that case? . */
4450 if (target_has_stack
&& inf_status
->restore_stack_info
)
4452 /* The point of catch_errors is that if the stack is clobbered,
4453 walking the stack might encounter a garbage pointer and
4454 error() trying to dereference it. */
4456 (restore_selected_frame
, &inf_status
->selected_frame_id
,
4457 "Unable to restore previously selected frame:\n",
4458 RETURN_MASK_ERROR
) == 0)
4459 /* Error in restoring the selected frame. Select the innermost
4461 select_frame (get_current_frame ());
4469 do_restore_inferior_status_cleanup (void *sts
)
4471 restore_inferior_status (sts
);
4475 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
4477 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
4481 discard_inferior_status (struct inferior_status
*inf_status
)
4483 /* See save_inferior_status for info on stop_bpstat. */
4484 bpstat_clear (&inf_status
->stop_bpstat
);
4485 regcache_xfree (inf_status
->registers
);
4490 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
4492 struct target_waitstatus last
;
4495 get_last_target_status (&last_ptid
, &last
);
4497 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
4500 if (!ptid_equal (last_ptid
, pid
))
4503 *child_pid
= last
.value
.related_pid
;
4508 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
4510 struct target_waitstatus last
;
4513 get_last_target_status (&last_ptid
, &last
);
4515 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
4518 if (!ptid_equal (last_ptid
, pid
))
4521 *child_pid
= last
.value
.related_pid
;
4526 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
4528 struct target_waitstatus last
;
4531 get_last_target_status (&last_ptid
, &last
);
4533 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
4536 if (!ptid_equal (last_ptid
, pid
))
4539 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
4543 /* Oft used ptids */
4545 ptid_t minus_one_ptid
;
4547 /* Create a ptid given the necessary PID, LWP, and TID components. */
4550 ptid_build (int pid
, long lwp
, long tid
)
4560 /* Create a ptid from just a pid. */
4563 pid_to_ptid (int pid
)
4565 return ptid_build (pid
, 0, 0);
4568 /* Fetch the pid (process id) component from a ptid. */
4571 ptid_get_pid (ptid_t ptid
)
4576 /* Fetch the lwp (lightweight process) component from a ptid. */
4579 ptid_get_lwp (ptid_t ptid
)
4584 /* Fetch the tid (thread id) component from a ptid. */
4587 ptid_get_tid (ptid_t ptid
)
4592 /* ptid_equal() is used to test equality of two ptids. */
4595 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
4597 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
4598 && ptid1
.tid
== ptid2
.tid
);
4601 /* restore_inferior_ptid() will be used by the cleanup machinery
4602 to restore the inferior_ptid value saved in a call to
4603 save_inferior_ptid(). */
4606 restore_inferior_ptid (void *arg
)
4608 ptid_t
*saved_ptid_ptr
= arg
;
4609 inferior_ptid
= *saved_ptid_ptr
;
4613 /* Save the value of inferior_ptid so that it may be restored by a
4614 later call to do_cleanups(). Returns the struct cleanup pointer
4615 needed for later doing the cleanup. */
4618 save_inferior_ptid (void)
4620 ptid_t
*saved_ptid_ptr
;
4622 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
4623 *saved_ptid_ptr
= inferior_ptid
;
4624 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
4629 static int non_stop_1
= 0;
4632 set_non_stop (char *args
, int from_tty
,
4633 struct cmd_list_element
*c
)
4635 if (target_has_execution
)
4637 non_stop_1
= non_stop
;
4638 error (_("Cannot change this setting while the inferior is running."));
4641 non_stop
= non_stop_1
;
4645 show_non_stop (struct ui_file
*file
, int from_tty
,
4646 struct cmd_list_element
*c
, const char *value
)
4648 fprintf_filtered (file
,
4649 _("Controlling the inferior in non-stop mode is %s.\n"),
4655 _initialize_infrun (void)
4659 struct cmd_list_element
*c
;
4661 add_info ("signals", signals_info
, _("\
4662 What debugger does when program gets various signals.\n\
4663 Specify a signal as argument to print info on that signal only."));
4664 add_info_alias ("handle", "signals", 0);
4666 add_com ("handle", class_run
, handle_command
, _("\
4667 Specify how to handle a signal.\n\
4668 Args are signals and actions to apply to those signals.\n\
4669 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4670 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4671 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4672 The special arg \"all\" is recognized to mean all signals except those\n\
4673 used by the debugger, typically SIGTRAP and SIGINT.\n\
4674 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4675 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4676 Stop means reenter debugger if this signal happens (implies print).\n\
4677 Print means print a message if this signal happens.\n\
4678 Pass means let program see this signal; otherwise program doesn't know.\n\
4679 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4680 Pass and Stop may be combined."));
4683 add_com ("lz", class_info
, signals_info
, _("\
4684 What debugger does when program gets various signals.\n\
4685 Specify a signal as argument to print info on that signal only."));
4686 add_com ("z", class_run
, xdb_handle_command
, _("\
4687 Specify how to handle a signal.\n\
4688 Args are signals and actions to apply to those signals.\n\
4689 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4690 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4691 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4692 The special arg \"all\" is recognized to mean all signals except those\n\
4693 used by the debugger, typically SIGTRAP and SIGINT.\n\
4694 Recognized actions include \"s\" (toggles between stop and nostop), \n\
4695 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4696 nopass), \"Q\" (noprint)\n\
4697 Stop means reenter debugger if this signal happens (implies print).\n\
4698 Print means print a message if this signal happens.\n\
4699 Pass means let program see this signal; otherwise program doesn't know.\n\
4700 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4701 Pass and Stop may be combined."));
4705 stop_command
= add_cmd ("stop", class_obscure
,
4706 not_just_help_class_command
, _("\
4707 There is no `stop' command, but you can set a hook on `stop'.\n\
4708 This allows you to set a list of commands to be run each time execution\n\
4709 of the program stops."), &cmdlist
);
4711 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
4712 Set inferior debugging."), _("\
4713 Show inferior debugging."), _("\
4714 When non-zero, inferior specific debugging is enabled."),
4717 &setdebuglist
, &showdebuglist
);
4719 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
4720 Set displaced stepping debugging."), _("\
4721 Show displaced stepping debugging."), _("\
4722 When non-zero, displaced stepping specific debugging is enabled."),
4724 show_debug_displaced
,
4725 &setdebuglist
, &showdebuglist
);
4727 add_setshow_boolean_cmd ("non-stop", no_class
,
4729 Set whether gdb controls the inferior in non-stop mode."), _("\
4730 Show whether gdb controls the inferior in non-stop mode."), _("\
4731 When debugging a multi-threaded program and this setting is\n\
4732 off (the default, also called all-stop mode), when one thread stops\n\
4733 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
4734 all other threads in the program while you interact with the thread of\n\
4735 interest. When you continue or step a thread, you can allow the other\n\
4736 threads to run, or have them remain stopped, but while you inspect any\n\
4737 thread's state, all threads stop.\n\
4739 In non-stop mode, when one thread stops, other threads can continue\n\
4740 to run freely. You'll be able to step each thread independently,\n\
4741 leave it stopped or free to run as needed."),
4747 numsigs
= (int) TARGET_SIGNAL_LAST
;
4748 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
4749 signal_print
= (unsigned char *)
4750 xmalloc (sizeof (signal_print
[0]) * numsigs
);
4751 signal_program
= (unsigned char *)
4752 xmalloc (sizeof (signal_program
[0]) * numsigs
);
4753 for (i
= 0; i
< numsigs
; i
++)
4756 signal_print
[i
] = 1;
4757 signal_program
[i
] = 1;
4760 /* Signals caused by debugger's own actions
4761 should not be given to the program afterwards. */
4762 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
4763 signal_program
[TARGET_SIGNAL_INT
] = 0;
4765 /* Signals that are not errors should not normally enter the debugger. */
4766 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
4767 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
4768 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
4769 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
4770 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
4771 signal_print
[TARGET_SIGNAL_PROF
] = 0;
4772 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
4773 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
4774 signal_stop
[TARGET_SIGNAL_IO
] = 0;
4775 signal_print
[TARGET_SIGNAL_IO
] = 0;
4776 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
4777 signal_print
[TARGET_SIGNAL_POLL
] = 0;
4778 signal_stop
[TARGET_SIGNAL_URG
] = 0;
4779 signal_print
[TARGET_SIGNAL_URG
] = 0;
4780 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
4781 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
4783 /* These signals are used internally by user-level thread
4784 implementations. (See signal(5) on Solaris.) Like the above
4785 signals, a healthy program receives and handles them as part of
4786 its normal operation. */
4787 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
4788 signal_print
[TARGET_SIGNAL_LWP
] = 0;
4789 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
4790 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
4791 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
4792 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
4794 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
4795 &stop_on_solib_events
, _("\
4796 Set stopping for shared library events."), _("\
4797 Show stopping for shared library events."), _("\
4798 If nonzero, gdb will give control to the user when the dynamic linker\n\
4799 notifies gdb of shared library events. The most common event of interest\n\
4800 to the user would be loading/unloading of a new library."),
4802 show_stop_on_solib_events
,
4803 &setlist
, &showlist
);
4805 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
4806 follow_fork_mode_kind_names
,
4807 &follow_fork_mode_string
, _("\
4808 Set debugger response to a program call of fork or vfork."), _("\
4809 Show debugger response to a program call of fork or vfork."), _("\
4810 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4811 parent - the original process is debugged after a fork\n\
4812 child - the new process is debugged after a fork\n\
4813 The unfollowed process will continue to run.\n\
4814 By default, the debugger will follow the parent process."),
4816 show_follow_fork_mode_string
,
4817 &setlist
, &showlist
);
4819 add_setshow_enum_cmd ("scheduler-locking", class_run
,
4820 scheduler_enums
, &scheduler_mode
, _("\
4821 Set mode for locking scheduler during execution."), _("\
4822 Show mode for locking scheduler during execution."), _("\
4823 off == no locking (threads may preempt at any time)\n\
4824 on == full locking (no thread except the current thread may run)\n\
4825 step == scheduler locked during every single-step operation.\n\
4826 In this mode, no other thread may run during a step command.\n\
4827 Other threads may run while stepping over a function call ('next')."),
4828 set_schedlock_func
, /* traps on target vector */
4829 show_scheduler_mode
,
4830 &setlist
, &showlist
);
4832 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
4833 Set mode of the step operation."), _("\
4834 Show mode of the step operation."), _("\
4835 When set, doing a step over a function without debug line information\n\
4836 will stop at the first instruction of that function. Otherwise, the\n\
4837 function is skipped and the step command stops at a different source line."),
4839 show_step_stop_if_no_debug
,
4840 &setlist
, &showlist
);
4842 add_setshow_boolean_cmd ("can-use-displaced-stepping", class_maintenance
,
4843 &can_use_displaced_stepping
, _("\
4844 Set debugger's willingness to use displaced stepping."), _("\
4845 Show debugger's willingness to use displaced stepping."), _("\
4846 If zero, gdb will not use displaced stepping to step over\n\
4847 breakpoints, even if such is supported by the target."),
4849 show_can_use_displaced_stepping
,
4850 &maintenance_set_cmdlist
,
4851 &maintenance_show_cmdlist
);
4853 /* ptid initializations */
4854 null_ptid
= ptid_build (0, 0, 0);
4855 minus_one_ptid
= ptid_build (-1, 0, 0);
4856 inferior_ptid
= null_ptid
;
4857 target_last_wait_ptid
= minus_one_ptid
;
4858 displaced_step_ptid
= null_ptid
;
4860 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);