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 /* Save register contents here when about to pop a stack dummy frame,
234 if-and-only-if proceed_to_finish is set.
235 Thus this contains the return value from the called function (assuming
236 values are returned in a register). */
238 struct regcache
*stop_registers
;
240 /* Nonzero after stop if current stack frame should be printed. */
242 static int stop_print_frame
;
244 /* This is a cached copy of the pid/waitstatus of the last event
245 returned by target_wait()/deprecated_target_wait_hook(). This
246 information is returned by get_last_target_status(). */
247 static ptid_t target_last_wait_ptid
;
248 static struct target_waitstatus target_last_waitstatus
;
250 static void context_switch (ptid_t ptid
);
252 void init_thread_stepping_state (struct thread_info
*tss
);
254 void init_infwait_state (void);
256 /* This is used to remember when a fork, vfork or exec event
257 was caught by a catchpoint, and thus the event is to be
258 followed at the next resume of the inferior, and not
262 enum target_waitkind kind
;
269 char *execd_pathname
;
273 static const char follow_fork_mode_child
[] = "child";
274 static const char follow_fork_mode_parent
[] = "parent";
276 static const char *follow_fork_mode_kind_names
[] = {
277 follow_fork_mode_child
,
278 follow_fork_mode_parent
,
282 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
284 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
285 struct cmd_list_element
*c
, const char *value
)
287 fprintf_filtered (file
, _("\
288 Debugger response to a program call of fork or vfork is \"%s\".\n"),
296 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
298 return target_follow_fork (follow_child
);
302 follow_inferior_reset_breakpoints (void)
304 struct thread_info
*tp
= inferior_thread ();
306 /* Was there a step_resume breakpoint? (There was if the user
307 did a "next" at the fork() call.) If so, explicitly reset its
310 step_resumes are a form of bp that are made to be per-thread.
311 Since we created the step_resume bp when the parent process
312 was being debugged, and now are switching to the child process,
313 from the breakpoint package's viewpoint, that's a switch of
314 "threads". We must update the bp's notion of which thread
315 it is for, or it'll be ignored when it triggers. */
317 if (tp
->step_resume_breakpoint
)
318 breakpoint_re_set_thread (tp
->step_resume_breakpoint
);
320 /* Reinsert all breakpoints in the child. The user may have set
321 breakpoints after catching the fork, in which case those
322 were never set in the child, but only in the parent. This makes
323 sure the inserted breakpoints match the breakpoint list. */
325 breakpoint_re_set ();
326 insert_breakpoints ();
329 /* EXECD_PATHNAME is assumed to be non-NULL. */
332 follow_exec (ptid_t pid
, char *execd_pathname
)
334 struct target_ops
*tgt
;
335 struct thread_info
*th
= inferior_thread ();
337 /* This is an exec event that we actually wish to pay attention to.
338 Refresh our symbol table to the newly exec'd program, remove any
341 If there are breakpoints, they aren't really inserted now,
342 since the exec() transformed our inferior into a fresh set
345 We want to preserve symbolic breakpoints on the list, since
346 we have hopes that they can be reset after the new a.out's
347 symbol table is read.
349 However, any "raw" breakpoints must be removed from the list
350 (e.g., the solib bp's), since their address is probably invalid
353 And, we DON'T want to call delete_breakpoints() here, since
354 that may write the bp's "shadow contents" (the instruction
355 value that was overwritten witha TRAP instruction). Since
356 we now have a new a.out, those shadow contents aren't valid. */
357 update_breakpoints_after_exec ();
359 /* If there was one, it's gone now. We cannot truly step-to-next
360 statement through an exec(). */
361 th
->step_resume_breakpoint
= NULL
;
362 th
->step_range_start
= 0;
363 th
->step_range_end
= 0;
365 /* What is this a.out's name? */
366 printf_unfiltered (_("Executing new program: %s\n"), execd_pathname
);
368 /* We've followed the inferior through an exec. Therefore, the
369 inferior has essentially been killed & reborn. */
371 gdb_flush (gdb_stdout
);
373 breakpoint_init_inferior (inf_execd
);
375 if (gdb_sysroot
&& *gdb_sysroot
)
377 char *name
= alloca (strlen (gdb_sysroot
)
378 + strlen (execd_pathname
)
380 strcpy (name
, gdb_sysroot
);
381 strcat (name
, execd_pathname
);
382 execd_pathname
= name
;
385 /* That a.out is now the one to use. */
386 exec_file_attach (execd_pathname
, 0);
388 /* Reset the shared library package. This ensures that we get a
389 shlib event when the child reaches "_start", at which point the
390 dld will have had a chance to initialize the child. */
391 /* Also, loading a symbol file below may trigger symbol lookups, and
392 we don't want those to be satisfied by the libraries of the
393 previous incarnation of this process. */
394 no_shared_libraries (NULL
, 0);
396 /* Load the main file's symbols. */
397 symbol_file_add_main (execd_pathname
, 0);
399 #ifdef SOLIB_CREATE_INFERIOR_HOOK
400 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
402 solib_create_inferior_hook ();
405 /* Reinsert all breakpoints. (Those which were symbolic have
406 been reset to the proper address in the new a.out, thanks
407 to symbol_file_command...) */
408 insert_breakpoints ();
410 /* The next resume of this inferior should bring it to the shlib
411 startup breakpoints. (If the user had also set bp's on
412 "main" from the old (parent) process, then they'll auto-
413 matically get reset there in the new process.) */
416 /* Non-zero if we just simulating a single-step. This is needed
417 because we cannot remove the breakpoints in the inferior process
418 until after the `wait' in `wait_for_inferior'. */
419 static int singlestep_breakpoints_inserted_p
= 0;
421 /* The thread we inserted single-step breakpoints for. */
422 static ptid_t singlestep_ptid
;
424 /* PC when we started this single-step. */
425 static CORE_ADDR singlestep_pc
;
427 /* If another thread hit the singlestep breakpoint, we save the original
428 thread here so that we can resume single-stepping it later. */
429 static ptid_t saved_singlestep_ptid
;
430 static int stepping_past_singlestep_breakpoint
;
432 /* If not equal to null_ptid, this means that after stepping over breakpoint
433 is finished, we need to switch to deferred_step_ptid, and step it.
435 The use case is when one thread has hit a breakpoint, and then the user
436 has switched to another thread and issued 'step'. We need to step over
437 breakpoint in the thread which hit the breakpoint, but then continue
438 stepping the thread user has selected. */
439 static ptid_t deferred_step_ptid
;
441 /* Displaced stepping. */
443 /* In non-stop debugging mode, we must take special care to manage
444 breakpoints properly; in particular, the traditional strategy for
445 stepping a thread past a breakpoint it has hit is unsuitable.
446 'Displaced stepping' is a tactic for stepping one thread past a
447 breakpoint it has hit while ensuring that other threads running
448 concurrently will hit the breakpoint as they should.
450 The traditional way to step a thread T off a breakpoint in a
451 multi-threaded program in all-stop mode is as follows:
453 a0) Initially, all threads are stopped, and breakpoints are not
455 a1) We single-step T, leaving breakpoints uninserted.
456 a2) We insert breakpoints, and resume all threads.
458 In non-stop debugging, however, this strategy is unsuitable: we
459 don't want to have to stop all threads in the system in order to
460 continue or step T past a breakpoint. Instead, we use displaced
463 n0) Initially, T is stopped, other threads are running, and
464 breakpoints are inserted.
465 n1) We copy the instruction "under" the breakpoint to a separate
466 location, outside the main code stream, making any adjustments
467 to the instruction, register, and memory state as directed by
469 n2) We single-step T over the instruction at its new location.
470 n3) We adjust the resulting register and memory state as directed
471 by T's architecture. This includes resetting T's PC to point
472 back into the main instruction stream.
475 This approach depends on the following gdbarch methods:
477 - gdbarch_max_insn_length and gdbarch_displaced_step_location
478 indicate where to copy the instruction, and how much space must
479 be reserved there. We use these in step n1.
481 - gdbarch_displaced_step_copy_insn copies a instruction to a new
482 address, and makes any necessary adjustments to the instruction,
483 register contents, and memory. We use this in step n1.
485 - gdbarch_displaced_step_fixup adjusts registers and memory after
486 we have successfuly single-stepped the instruction, to yield the
487 same effect the instruction would have had if we had executed it
488 at its original address. We use this in step n3.
490 - gdbarch_displaced_step_free_closure provides cleanup.
492 The gdbarch_displaced_step_copy_insn and
493 gdbarch_displaced_step_fixup functions must be written so that
494 copying an instruction with gdbarch_displaced_step_copy_insn,
495 single-stepping across the copied instruction, and then applying
496 gdbarch_displaced_insn_fixup should have the same effects on the
497 thread's memory and registers as stepping the instruction in place
498 would have. Exactly which responsibilities fall to the copy and
499 which fall to the fixup is up to the author of those functions.
501 See the comments in gdbarch.sh for details.
503 Note that displaced stepping and software single-step cannot
504 currently be used in combination, although with some care I think
505 they could be made to. Software single-step works by placing
506 breakpoints on all possible subsequent instructions; if the
507 displaced instruction is a PC-relative jump, those breakpoints
508 could fall in very strange places --- on pages that aren't
509 executable, or at addresses that are not proper instruction
510 boundaries. (We do generally let other threads run while we wait
511 to hit the software single-step breakpoint, and they might
512 encounter such a corrupted instruction.) One way to work around
513 this would be to have gdbarch_displaced_step_copy_insn fully
514 simulate the effect of PC-relative instructions (and return NULL)
515 on architectures that use software single-stepping.
517 In non-stop mode, we can have independent and simultaneous step
518 requests, so more than one thread may need to simultaneously step
519 over a breakpoint. The current implementation assumes there is
520 only one scratch space per process. In this case, we have to
521 serialize access to the scratch space. If thread A wants to step
522 over a breakpoint, but we are currently waiting for some other
523 thread to complete a displaced step, we leave thread A stopped and
524 place it in the displaced_step_request_queue. Whenever a displaced
525 step finishes, we pick the next thread in the queue and start a new
526 displaced step operation on it. See displaced_step_prepare and
527 displaced_step_fixup for details. */
529 /* If this is not null_ptid, this is the thread carrying out a
530 displaced single-step. This thread's state will require fixing up
531 once it has completed its step. */
532 static ptid_t displaced_step_ptid
;
534 struct displaced_step_request
537 struct displaced_step_request
*next
;
540 /* A queue of pending displaced stepping requests. */
541 struct displaced_step_request
*displaced_step_request_queue
;
543 /* The architecture the thread had when we stepped it. */
544 static struct gdbarch
*displaced_step_gdbarch
;
546 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
547 for post-step cleanup. */
548 static struct displaced_step_closure
*displaced_step_closure
;
550 /* The address of the original instruction, and the copy we made. */
551 static CORE_ADDR displaced_step_original
, displaced_step_copy
;
553 /* Saved contents of copy area. */
554 static gdb_byte
*displaced_step_saved_copy
;
556 /* When this is non-zero, we are allowed to use displaced stepping, if
557 the architecture supports it. When this is zero, we use
558 traditional the hold-and-step approach. */
559 int can_use_displaced_stepping
= 1;
561 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
562 struct cmd_list_element
*c
,
565 fprintf_filtered (file
, _("\
566 Debugger's willingness to use displaced stepping to step over "
567 "breakpoints is %s.\n"), value
);
570 /* Return non-zero if displaced stepping is enabled, and can be used
573 use_displaced_stepping (struct gdbarch
*gdbarch
)
575 return (can_use_displaced_stepping
576 && gdbarch_displaced_step_copy_insn_p (gdbarch
));
579 /* Clean out any stray displaced stepping state. */
581 displaced_step_clear (void)
583 /* Indicate that there is no cleanup pending. */
584 displaced_step_ptid
= null_ptid
;
586 if (displaced_step_closure
)
588 gdbarch_displaced_step_free_closure (displaced_step_gdbarch
,
589 displaced_step_closure
);
590 displaced_step_closure
= NULL
;
595 cleanup_displaced_step_closure (void *ptr
)
597 struct displaced_step_closure
*closure
= ptr
;
599 gdbarch_displaced_step_free_closure (current_gdbarch
, closure
);
602 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
604 displaced_step_dump_bytes (struct ui_file
*file
,
610 for (i
= 0; i
< len
; i
++)
611 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
612 fputs_unfiltered ("\n", file
);
615 /* Prepare to single-step, using displaced stepping.
617 Note that we cannot use displaced stepping when we have a signal to
618 deliver. If we have a signal to deliver and an instruction to step
619 over, then after the step, there will be no indication from the
620 target whether the thread entered a signal handler or ignored the
621 signal and stepped over the instruction successfully --- both cases
622 result in a simple SIGTRAP. In the first case we mustn't do a
623 fixup, and in the second case we must --- but we can't tell which.
624 Comments in the code for 'random signals' in handle_inferior_event
625 explain how we handle this case instead.
627 Returns 1 if preparing was successful -- this thread is going to be
628 stepped now; or 0 if displaced stepping this thread got queued. */
630 displaced_step_prepare (ptid_t ptid
)
632 struct cleanup
*old_cleanups
, *ignore_cleanups
;
633 struct regcache
*regcache
= get_thread_regcache (ptid
);
634 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
635 CORE_ADDR original
, copy
;
637 struct displaced_step_closure
*closure
;
639 /* We should never reach this function if the architecture does not
640 support displaced stepping. */
641 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
643 /* For the first cut, we're displaced stepping one thread at a
646 if (!ptid_equal (displaced_step_ptid
, null_ptid
))
648 /* Already waiting for a displaced step to finish. Defer this
649 request and place in queue. */
650 struct displaced_step_request
*req
, *new_req
;
653 fprintf_unfiltered (gdb_stdlog
,
654 "displaced: defering step of %s\n",
655 target_pid_to_str (ptid
));
657 new_req
= xmalloc (sizeof (*new_req
));
658 new_req
->ptid
= ptid
;
659 new_req
->next
= NULL
;
661 if (displaced_step_request_queue
)
663 for (req
= displaced_step_request_queue
;
670 displaced_step_request_queue
= new_req
;
677 fprintf_unfiltered (gdb_stdlog
,
678 "displaced: stepping %s now\n",
679 target_pid_to_str (ptid
));
682 displaced_step_clear ();
684 old_cleanups
= save_inferior_ptid ();
685 inferior_ptid
= ptid
;
687 original
= regcache_read_pc (regcache
);
689 copy
= gdbarch_displaced_step_location (gdbarch
);
690 len
= gdbarch_max_insn_length (gdbarch
);
692 /* Save the original contents of the copy area. */
693 displaced_step_saved_copy
= xmalloc (len
);
694 ignore_cleanups
= make_cleanup (free_current_contents
,
695 &displaced_step_saved_copy
);
696 read_memory (copy
, displaced_step_saved_copy
, len
);
699 fprintf_unfiltered (gdb_stdlog
, "displaced: saved 0x%s: ",
701 displaced_step_dump_bytes (gdb_stdlog
, displaced_step_saved_copy
, len
);
704 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
705 original
, copy
, regcache
);
707 /* We don't support the fully-simulated case at present. */
708 gdb_assert (closure
);
710 make_cleanup (cleanup_displaced_step_closure
, closure
);
712 /* Resume execution at the copy. */
713 regcache_write_pc (regcache
, copy
);
715 discard_cleanups (ignore_cleanups
);
717 do_cleanups (old_cleanups
);
720 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to 0x%s\n",
723 /* Save the information we need to fix things up if the step
725 displaced_step_ptid
= ptid
;
726 displaced_step_gdbarch
= gdbarch
;
727 displaced_step_closure
= closure
;
728 displaced_step_original
= original
;
729 displaced_step_copy
= copy
;
734 displaced_step_clear_cleanup (void *ignore
)
736 displaced_step_clear ();
740 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
, const gdb_byte
*myaddr
, int len
)
742 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
743 inferior_ptid
= ptid
;
744 write_memory (memaddr
, myaddr
, len
);
745 do_cleanups (ptid_cleanup
);
749 displaced_step_fixup (ptid_t event_ptid
, enum target_signal signal
)
751 struct cleanup
*old_cleanups
;
753 /* Was this event for the pid we displaced? */
754 if (ptid_equal (displaced_step_ptid
, null_ptid
)
755 || ! ptid_equal (displaced_step_ptid
, event_ptid
))
758 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, 0);
760 /* Restore the contents of the copy area. */
762 ULONGEST len
= gdbarch_max_insn_length (displaced_step_gdbarch
);
763 write_memory_ptid (displaced_step_ptid
, displaced_step_copy
,
764 displaced_step_saved_copy
, len
);
766 fprintf_unfiltered (gdb_stdlog
, "displaced: restored 0x%s\n",
767 paddr_nz (displaced_step_copy
));
770 /* Did the instruction complete successfully? */
771 if (signal
== TARGET_SIGNAL_TRAP
)
773 /* Fix up the resulting state. */
774 gdbarch_displaced_step_fixup (displaced_step_gdbarch
,
775 displaced_step_closure
,
776 displaced_step_original
,
778 get_thread_regcache (displaced_step_ptid
));
782 /* Since the instruction didn't complete, all we can do is
784 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
785 CORE_ADDR pc
= regcache_read_pc (regcache
);
786 pc
= displaced_step_original
+ (pc
- displaced_step_copy
);
787 regcache_write_pc (regcache
, pc
);
790 do_cleanups (old_cleanups
);
792 displaced_step_ptid
= null_ptid
;
794 /* Are there any pending displaced stepping requests? If so, run
796 while (displaced_step_request_queue
)
798 struct displaced_step_request
*head
;
802 head
= displaced_step_request_queue
;
804 displaced_step_request_queue
= head
->next
;
807 context_switch (ptid
);
809 actual_pc
= read_pc ();
811 if (breakpoint_here_p (actual_pc
))
814 fprintf_unfiltered (gdb_stdlog
,
815 "displaced: stepping queued %s now\n",
816 target_pid_to_str (ptid
));
818 displaced_step_prepare (ptid
);
824 fprintf_unfiltered (gdb_stdlog
, "displaced: run 0x%s: ",
825 paddr_nz (actual_pc
));
826 read_memory (actual_pc
, buf
, sizeof (buf
));
827 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
830 target_resume (ptid
, 1, TARGET_SIGNAL_0
);
832 /* Done, we're stepping a thread. */
838 struct thread_info
*tp
= inferior_thread ();
840 /* The breakpoint we were sitting under has since been
842 tp
->trap_expected
= 0;
844 /* Go back to what we were trying to do. */
845 step
= currently_stepping (tp
);
848 fprintf_unfiltered (gdb_stdlog
, "breakpoint is gone %s: step(%d)\n",
849 target_pid_to_str (tp
->ptid
), step
);
851 target_resume (ptid
, step
, TARGET_SIGNAL_0
);
852 tp
->stop_signal
= TARGET_SIGNAL_0
;
854 /* This request was discarded. See if there's any other
855 thread waiting for its turn. */
860 /* Update global variables holding ptids to hold NEW_PTID if they were
863 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
865 struct displaced_step_request
*it
;
867 if (ptid_equal (inferior_ptid
, old_ptid
))
868 inferior_ptid
= new_ptid
;
870 if (ptid_equal (singlestep_ptid
, old_ptid
))
871 singlestep_ptid
= new_ptid
;
873 if (ptid_equal (displaced_step_ptid
, old_ptid
))
874 displaced_step_ptid
= new_ptid
;
876 if (ptid_equal (deferred_step_ptid
, old_ptid
))
877 deferred_step_ptid
= new_ptid
;
879 for (it
= displaced_step_request_queue
; it
; it
= it
->next
)
880 if (ptid_equal (it
->ptid
, old_ptid
))
887 /* Things to clean up if we QUIT out of resume (). */
889 resume_cleanups (void *ignore
)
894 static const char schedlock_off
[] = "off";
895 static const char schedlock_on
[] = "on";
896 static const char schedlock_step
[] = "step";
897 static const char *scheduler_enums
[] = {
903 static const char *scheduler_mode
= schedlock_off
;
905 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
906 struct cmd_list_element
*c
, const char *value
)
908 fprintf_filtered (file
, _("\
909 Mode for locking scheduler during execution is \"%s\".\n"),
914 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
916 if (!target_can_lock_scheduler
)
918 scheduler_mode
= schedlock_off
;
919 error (_("Target '%s' cannot support this command."), target_shortname
);
924 /* Resume the inferior, but allow a QUIT. This is useful if the user
925 wants to interrupt some lengthy single-stepping operation
926 (for child processes, the SIGINT goes to the inferior, and so
927 we get a SIGINT random_signal, but for remote debugging and perhaps
928 other targets, that's not true).
930 STEP nonzero if we should step (zero to continue instead).
931 SIG is the signal to give the inferior (zero for none). */
933 resume (int step
, enum target_signal sig
)
935 int should_resume
= 1;
936 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
937 struct regcache
*regcache
= get_current_regcache ();
938 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
939 struct thread_info
*tp
= inferior_thread ();
940 CORE_ADDR pc
= regcache_read_pc (regcache
);
944 fprintf_unfiltered (gdb_stdlog
,
945 "infrun: resume (step=%d, signal=%d), "
946 "trap_expected=%d\n",
947 step
, sig
, tp
->trap_expected
);
949 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
950 over an instruction that causes a page fault without triggering
951 a hardware watchpoint. The kernel properly notices that it shouldn't
952 stop, because the hardware watchpoint is not triggered, but it forgets
953 the step request and continues the program normally.
954 Work around the problem by removing hardware watchpoints if a step is
955 requested, GDB will check for a hardware watchpoint trigger after the
957 if (CANNOT_STEP_HW_WATCHPOINTS
&& step
)
958 remove_hw_watchpoints ();
961 /* Normally, by the time we reach `resume', the breakpoints are either
962 removed or inserted, as appropriate. The exception is if we're sitting
963 at a permanent breakpoint; we need to step over it, but permanent
964 breakpoints can't be removed. So we have to test for it here. */
965 if (breakpoint_here_p (pc
) == permanent_breakpoint_here
)
967 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
968 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
971 The program is stopped at a permanent breakpoint, but GDB does not know\n\
972 how to step past a permanent breakpoint on this architecture. Try using\n\
973 a command like `return' or `jump' to continue execution."));
976 /* If enabled, step over breakpoints by executing a copy of the
977 instruction at a different address.
979 We can't use displaced stepping when we have a signal to deliver;
980 the comments for displaced_step_prepare explain why. The
981 comments in the handle_inferior event for dealing with 'random
982 signals' explain what we do instead. */
983 if (use_displaced_stepping (gdbarch
)
985 && sig
== TARGET_SIGNAL_0
)
987 if (!displaced_step_prepare (inferior_ptid
))
989 /* Got placed in displaced stepping queue. Will be resumed
990 later when all the currently queued displaced stepping
991 requests finish. The thread is not executing at this point,
992 and the call to set_executing will be made later. But we
993 need to call set_running here, since from frontend point of view,
994 the thread is running. */
995 set_running (inferior_ptid
, 1);
996 discard_cleanups (old_cleanups
);
1001 if (step
&& gdbarch_software_single_step_p (gdbarch
))
1003 /* Do it the hard way, w/temp breakpoints */
1004 if (gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1006 /* ...and don't ask hardware to do it. */
1008 /* and do not pull these breakpoints until after a `wait' in
1009 `wait_for_inferior' */
1010 singlestep_breakpoints_inserted_p
= 1;
1011 singlestep_ptid
= inferior_ptid
;
1016 /* If there were any forks/vforks/execs that were caught and are
1017 now to be followed, then do so. */
1018 switch (pending_follow
.kind
)
1020 case TARGET_WAITKIND_FORKED
:
1021 case TARGET_WAITKIND_VFORKED
:
1022 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
1027 case TARGET_WAITKIND_EXECD
:
1028 /* follow_exec is called as soon as the exec event is seen. */
1029 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
1036 /* Install inferior's terminal modes. */
1037 target_terminal_inferior ();
1043 resume_ptid
= RESUME_ALL
; /* Default */
1045 /* If STEP is set, it's a request to use hardware stepping
1046 facilities. But in that case, we should never
1047 use singlestep breakpoint. */
1048 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1050 if (singlestep_breakpoints_inserted_p
1051 && stepping_past_singlestep_breakpoint
)
1053 /* The situation here is as follows. In thread T1 we wanted to
1054 single-step. Lacking hardware single-stepping we've
1055 set breakpoint at the PC of the next instruction -- call it
1056 P. After resuming, we've hit that breakpoint in thread T2.
1057 Now we've removed original breakpoint, inserted breakpoint
1058 at P+1, and try to step to advance T2 past breakpoint.
1059 We need to step only T2, as if T1 is allowed to freely run,
1060 it can run past P, and if other threads are allowed to run,
1061 they can hit breakpoint at P+1, and nested hits of single-step
1062 breakpoints is not something we'd want -- that's complicated
1063 to support, and has no value. */
1064 resume_ptid
= inferior_ptid
;
1067 if ((step
|| singlestep_breakpoints_inserted_p
)
1068 && tp
->trap_expected
)
1070 /* We're allowing a thread to run past a breakpoint it has
1071 hit, by single-stepping the thread with the breakpoint
1072 removed. In which case, we need to single-step only this
1073 thread, and keep others stopped, as they can miss this
1074 breakpoint if allowed to run.
1076 The current code actually removes all breakpoints when
1077 doing this, not just the one being stepped over, so if we
1078 let other threads run, we can actually miss any
1079 breakpoint, not just the one at PC. */
1080 resume_ptid
= inferior_ptid
;
1085 /* With non-stop mode on, threads are always handled
1087 resume_ptid
= inferior_ptid
;
1089 else if ((scheduler_mode
== schedlock_on
)
1090 || (scheduler_mode
== schedlock_step
1091 && (step
|| singlestep_breakpoints_inserted_p
)))
1093 /* User-settable 'scheduler' mode requires solo thread resume. */
1094 resume_ptid
= inferior_ptid
;
1097 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1099 /* Most targets can step a breakpoint instruction, thus
1100 executing it normally. But if this one cannot, just
1101 continue and we will hit it anyway. */
1102 if (step
&& breakpoint_inserted_here_p (pc
))
1107 && use_displaced_stepping (gdbarch
)
1108 && tp
->trap_expected
)
1110 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1111 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1114 fprintf_unfiltered (gdb_stdlog
, "displaced: run 0x%s: ",
1115 paddr_nz (actual_pc
));
1116 read_memory (actual_pc
, buf
, sizeof (buf
));
1117 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1120 target_resume (resume_ptid
, step
, sig
);
1122 /* Avoid confusing the next resume, if the next stop/resume
1123 happens to apply to another thread. */
1124 tp
->stop_signal
= TARGET_SIGNAL_0
;
1127 discard_cleanups (old_cleanups
);
1132 /* Clear out all variables saying what to do when inferior is continued.
1133 First do this, then set the ones you want, then call `proceed'. */
1136 clear_proceed_status (void)
1138 if (!ptid_equal (inferior_ptid
, null_ptid
))
1140 struct thread_info
*tp
;
1141 struct inferior
*inferior
;
1143 tp
= inferior_thread ();
1145 tp
->trap_expected
= 0;
1146 tp
->step_range_start
= 0;
1147 tp
->step_range_end
= 0;
1148 tp
->step_frame_id
= null_frame_id
;
1149 tp
->step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1153 tp
->proceed_to_finish
= 0;
1155 /* Discard any remaining commands or status from previous
1157 bpstat_clear (&tp
->stop_bpstat
);
1159 inferior
= current_inferior ();
1160 inferior
->stop_soon
= NO_STOP_QUIETLY
;
1163 stop_after_trap
= 0;
1164 breakpoint_proceeded
= 1; /* We're about to proceed... */
1168 regcache_xfree (stop_registers
);
1169 stop_registers
= NULL
;
1173 /* This should be suitable for any targets that support threads. */
1176 prepare_to_proceed (int step
)
1179 struct target_waitstatus wait_status
;
1181 /* Get the last target status returned by target_wait(). */
1182 get_last_target_status (&wait_ptid
, &wait_status
);
1184 /* Make sure we were stopped at a breakpoint. */
1185 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
1186 || wait_status
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1191 /* Switched over from WAIT_PID. */
1192 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
1193 && !ptid_equal (inferior_ptid
, wait_ptid
))
1195 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
1197 if (breakpoint_here_p (regcache_read_pc (regcache
)))
1199 /* If stepping, remember current thread to switch back to. */
1201 deferred_step_ptid
= inferior_ptid
;
1203 /* Switch back to WAIT_PID thread. */
1204 switch_to_thread (wait_ptid
);
1206 /* We return 1 to indicate that there is a breakpoint here,
1207 so we need to step over it before continuing to avoid
1208 hitting it straight away. */
1216 /* Basic routine for continuing the program in various fashions.
1218 ADDR is the address to resume at, or -1 for resume where stopped.
1219 SIGGNAL is the signal to give it, or 0 for none,
1220 or -1 for act according to how it stopped.
1221 STEP is nonzero if should trap after one instruction.
1222 -1 means return after that and print nothing.
1223 You should probably set various step_... variables
1224 before calling here, if you are stepping.
1226 You should call clear_proceed_status before calling proceed. */
1229 proceed (CORE_ADDR addr
, enum target_signal siggnal
, int step
)
1231 struct regcache
*regcache
= get_current_regcache ();
1232 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1233 struct thread_info
*tp
;
1234 CORE_ADDR pc
= regcache_read_pc (regcache
);
1236 enum target_signal stop_signal
;
1239 step_start_function
= find_pc_function (pc
);
1241 stop_after_trap
= 1;
1243 if (addr
== (CORE_ADDR
) -1)
1245 if (pc
== stop_pc
&& breakpoint_here_p (pc
))
1246 /* There is a breakpoint at the address we will resume at,
1247 step one instruction before inserting breakpoints so that
1248 we do not stop right away (and report a second hit at this
1251 else if (gdbarch_single_step_through_delay_p (gdbarch
)
1252 && gdbarch_single_step_through_delay (gdbarch
,
1253 get_current_frame ()))
1254 /* We stepped onto an instruction that needs to be stepped
1255 again before re-inserting the breakpoint, do so. */
1260 regcache_write_pc (regcache
, addr
);
1264 fprintf_unfiltered (gdb_stdlog
,
1265 "infrun: proceed (addr=0x%s, signal=%d, step=%d)\n",
1266 paddr_nz (addr
), siggnal
, step
);
1269 /* In non-stop, each thread is handled individually. The context
1270 must already be set to the right thread here. */
1274 /* In a multi-threaded task we may select another thread and
1275 then continue or step.
1277 But if the old thread was stopped at a breakpoint, it will
1278 immediately cause another breakpoint stop without any
1279 execution (i.e. it will report a breakpoint hit incorrectly).
1280 So we must step over it first.
1282 prepare_to_proceed checks the current thread against the
1283 thread that reported the most recent event. If a step-over
1284 is required it returns TRUE and sets the current thread to
1286 if (prepare_to_proceed (step
))
1290 /* prepare_to_proceed may change the current thread. */
1291 tp
= inferior_thread ();
1295 tp
->trap_expected
= 1;
1296 /* If displaced stepping is enabled, we can step over the
1297 breakpoint without hitting it, so leave all breakpoints
1298 inserted. Otherwise we need to disable all breakpoints, step
1299 one instruction, and then re-add them when that step is
1301 if (!use_displaced_stepping (gdbarch
))
1302 remove_breakpoints ();
1305 /* We can insert breakpoints if we're not trying to step over one,
1306 or if we are stepping over one but we're using displaced stepping
1308 if (! tp
->trap_expected
|| use_displaced_stepping (gdbarch
))
1309 insert_breakpoints ();
1313 /* Pass the last stop signal to the thread we're resuming,
1314 irrespective of whether the current thread is the thread that
1315 got the last event or not. This was historically GDB's
1316 behaviour before keeping a stop_signal per thread. */
1318 struct thread_info
*last_thread
;
1320 struct target_waitstatus last_status
;
1322 get_last_target_status (&last_ptid
, &last_status
);
1323 if (!ptid_equal (inferior_ptid
, last_ptid
)
1324 && !ptid_equal (last_ptid
, null_ptid
)
1325 && !ptid_equal (last_ptid
, minus_one_ptid
))
1327 last_thread
= find_thread_pid (last_ptid
);
1330 tp
->stop_signal
= last_thread
->stop_signal
;
1331 last_thread
->stop_signal
= TARGET_SIGNAL_0
;
1336 if (siggnal
!= TARGET_SIGNAL_DEFAULT
)
1337 tp
->stop_signal
= siggnal
;
1338 /* If this signal should not be seen by program,
1339 give it zero. Used for debugging signals. */
1340 else if (!signal_program
[tp
->stop_signal
])
1341 tp
->stop_signal
= TARGET_SIGNAL_0
;
1343 annotate_starting ();
1345 /* Make sure that output from GDB appears before output from the
1347 gdb_flush (gdb_stdout
);
1349 /* Refresh prev_pc value just prior to resuming. This used to be
1350 done in stop_stepping, however, setting prev_pc there did not handle
1351 scenarios such as inferior function calls or returning from
1352 a function via the return command. In those cases, the prev_pc
1353 value was not set properly for subsequent commands. The prev_pc value
1354 is used to initialize the starting line number in the ecs. With an
1355 invalid value, the gdb next command ends up stopping at the position
1356 represented by the next line table entry past our start position.
1357 On platforms that generate one line table entry per line, this
1358 is not a problem. However, on the ia64, the compiler generates
1359 extraneous line table entries that do not increase the line number.
1360 When we issue the gdb next command on the ia64 after an inferior call
1361 or a return command, we often end up a few instructions forward, still
1362 within the original line we started.
1364 An attempt was made to have init_execution_control_state () refresh
1365 the prev_pc value before calculating the line number. This approach
1366 did not work because on platforms that use ptrace, the pc register
1367 cannot be read unless the inferior is stopped. At that point, we
1368 are not guaranteed the inferior is stopped and so the regcache_read_pc ()
1369 call can fail. Setting the prev_pc value here ensures the value is
1370 updated correctly when the inferior is stopped. */
1371 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
1373 /* Fill in with reasonable starting values. */
1374 init_thread_stepping_state (tp
);
1376 /* Reset to normal state. */
1377 init_infwait_state ();
1379 /* Resume inferior. */
1380 resume (oneproc
|| step
|| bpstat_should_step (), tp
->stop_signal
);
1382 /* Wait for it to stop (if not standalone)
1383 and in any case decode why it stopped, and act accordingly. */
1384 /* Do this only if we are not using the event loop, or if the target
1385 does not support asynchronous execution. */
1386 if (!target_can_async_p ())
1388 wait_for_inferior (0);
1394 /* Start remote-debugging of a machine over a serial link. */
1397 start_remote (int from_tty
)
1399 struct inferior
*inferior
;
1400 init_wait_for_inferior ();
1402 inferior
= current_inferior ();
1403 inferior
->stop_soon
= STOP_QUIETLY_REMOTE
;
1405 /* Always go on waiting for the target, regardless of the mode. */
1406 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1407 indicate to wait_for_inferior that a target should timeout if
1408 nothing is returned (instead of just blocking). Because of this,
1409 targets expecting an immediate response need to, internally, set
1410 things up so that the target_wait() is forced to eventually
1412 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1413 differentiate to its caller what the state of the target is after
1414 the initial open has been performed. Here we're assuming that
1415 the target has stopped. It should be possible to eventually have
1416 target_open() return to the caller an indication that the target
1417 is currently running and GDB state should be set to the same as
1418 for an async run. */
1419 wait_for_inferior (0);
1421 /* Now that the inferior has stopped, do any bookkeeping like
1422 loading shared libraries. We want to do this before normal_stop,
1423 so that the displayed frame is up to date. */
1424 post_create_inferior (¤t_target
, from_tty
);
1429 /* Initialize static vars when a new inferior begins. */
1432 init_wait_for_inferior (void)
1434 /* These are meaningless until the first time through wait_for_inferior. */
1436 breakpoint_init_inferior (inf_starting
);
1438 /* The first resume is not following a fork/vfork/exec. */
1439 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
; /* I.e., none. */
1441 clear_proceed_status ();
1443 stepping_past_singlestep_breakpoint
= 0;
1444 deferred_step_ptid
= null_ptid
;
1446 target_last_wait_ptid
= minus_one_ptid
;
1448 previous_inferior_ptid
= null_ptid
;
1449 init_infwait_state ();
1451 displaced_step_clear ();
1455 /* This enum encodes possible reasons for doing a target_wait, so that
1456 wfi can call target_wait in one place. (Ultimately the call will be
1457 moved out of the infinite loop entirely.) */
1461 infwait_normal_state
,
1462 infwait_thread_hop_state
,
1463 infwait_step_watch_state
,
1464 infwait_nonstep_watch_state
1467 /* Why did the inferior stop? Used to print the appropriate messages
1468 to the interface from within handle_inferior_event(). */
1469 enum inferior_stop_reason
1471 /* Step, next, nexti, stepi finished. */
1473 /* Inferior terminated by signal. */
1475 /* Inferior exited. */
1477 /* Inferior received signal, and user asked to be notified. */
1481 /* The PTID we'll do a target_wait on.*/
1484 /* Current inferior wait state. */
1485 enum infwait_states infwait_state
;
1487 /* Data to be passed around while handling an event. This data is
1488 discarded between events. */
1489 struct execution_control_state
1492 /* The thread that got the event, if this was a thread event; NULL
1494 struct thread_info
*event_thread
;
1496 struct target_waitstatus ws
;
1498 CORE_ADDR stop_func_start
;
1499 CORE_ADDR stop_func_end
;
1500 char *stop_func_name
;
1501 int new_thread_event
;
1505 void init_execution_control_state (struct execution_control_state
*ecs
);
1507 void handle_inferior_event (struct execution_control_state
*ecs
);
1509 static void step_into_function (struct execution_control_state
*ecs
);
1510 static void insert_step_resume_breakpoint_at_frame (struct frame_info
*step_frame
);
1511 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
1512 static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
1513 struct frame_id sr_id
);
1514 static void insert_longjmp_resume_breakpoint (CORE_ADDR
);
1516 static void stop_stepping (struct execution_control_state
*ecs
);
1517 static void prepare_to_wait (struct execution_control_state
*ecs
);
1518 static void keep_going (struct execution_control_state
*ecs
);
1519 static void print_stop_reason (enum inferior_stop_reason stop_reason
,
1522 /* Callback for iterate_over_threads. */
1525 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
1527 if (is_exited (info
->ptid
))
1530 delete_step_resume_breakpoint (info
);
1534 /* In all-stop, delete the step resume breakpoint of any thread that
1535 had one. In non-stop, delete the step resume breakpoint of the
1536 thread that just stopped. */
1539 delete_step_thread_step_resume_breakpoint (void)
1541 if (!target_has_execution
1542 || ptid_equal (inferior_ptid
, null_ptid
))
1543 /* If the inferior has exited, we have already deleted the step
1544 resume breakpoints out of GDB's lists. */
1549 /* If in non-stop mode, only delete the step-resume or
1550 longjmp-resume breakpoint of the thread that just stopped
1552 struct thread_info
*tp
= inferior_thread ();
1553 delete_step_resume_breakpoint (tp
);
1556 /* In all-stop mode, delete all step-resume and longjmp-resume
1557 breakpoints of any thread that had them. */
1558 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
1561 /* A cleanup wrapper. */
1564 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
1566 delete_step_thread_step_resume_breakpoint ();
1569 /* Wait for control to return from inferior to debugger.
1571 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
1572 as if they were SIGTRAP signals. This can be useful during
1573 the startup sequence on some targets such as HP/UX, where
1574 we receive an EXEC event instead of the expected SIGTRAP.
1576 If inferior gets a signal, we may decide to start it up again
1577 instead of returning. That is why there is a loop in this function.
1578 When this function actually returns it means the inferior
1579 should be left stopped and GDB should read more commands. */
1582 wait_for_inferior (int treat_exec_as_sigtrap
)
1584 struct cleanup
*old_cleanups
;
1585 struct execution_control_state ecss
;
1586 struct execution_control_state
*ecs
;
1590 (gdb_stdlog
, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
1591 treat_exec_as_sigtrap
);
1594 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
1597 memset (ecs
, 0, sizeof (*ecs
));
1599 overlay_cache_invalid
= 1;
1601 /* We'll update this if & when we switch to a new thread. */
1602 previous_inferior_ptid
= inferior_ptid
;
1604 /* We have to invalidate the registers BEFORE calling target_wait
1605 because they can be loaded from the target while in target_wait.
1606 This makes remote debugging a bit more efficient for those
1607 targets that provide critical registers as part of their normal
1608 status mechanism. */
1610 registers_changed ();
1614 if (deprecated_target_wait_hook
)
1615 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
);
1617 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
);
1619 if (treat_exec_as_sigtrap
&& ecs
->ws
.kind
== TARGET_WAITKIND_EXECD
)
1621 xfree (ecs
->ws
.value
.execd_pathname
);
1622 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
1623 ecs
->ws
.value
.sig
= TARGET_SIGNAL_TRAP
;
1626 /* Now figure out what to do with the result of the result. */
1627 handle_inferior_event (ecs
);
1629 if (!ecs
->wait_some_more
)
1633 do_cleanups (old_cleanups
);
1636 /* Asynchronous version of wait_for_inferior. It is called by the
1637 event loop whenever a change of state is detected on the file
1638 descriptor corresponding to the target. It can be called more than
1639 once to complete a single execution command. In such cases we need
1640 to keep the state in a global variable ECSS. If it is the last time
1641 that this function is called for a single execution command, then
1642 report to the user that the inferior has stopped, and do the
1643 necessary cleanups. */
1646 fetch_inferior_event (void *client_data
)
1648 struct execution_control_state ecss
;
1649 struct execution_control_state
*ecs
= &ecss
;
1650 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
1651 int was_sync
= sync_execution
;
1653 memset (ecs
, 0, sizeof (*ecs
));
1655 overlay_cache_invalid
= 1;
1657 /* We can only rely on wait_for_more being correct before handling
1658 the event in all-stop, but previous_inferior_ptid isn't used in
1660 if (!ecs
->wait_some_more
)
1661 /* We'll update this if & when we switch to a new thread. */
1662 previous_inferior_ptid
= inferior_ptid
;
1665 /* In non-stop mode, the user/frontend should not notice a thread
1666 switch due to internal events. Make sure we reverse to the
1667 user selected thread and frame after handling the event and
1668 running any breakpoint commands. */
1669 make_cleanup_restore_current_thread ();
1671 /* We have to invalidate the registers BEFORE calling target_wait
1672 because they can be loaded from the target while in target_wait.
1673 This makes remote debugging a bit more efficient for those
1674 targets that provide critical registers as part of their normal
1675 status mechanism. */
1677 registers_changed ();
1679 if (deprecated_target_wait_hook
)
1681 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
);
1683 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
);
1686 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
1687 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1688 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
1689 /* In non-stop mode, each thread is handled individually. Switch
1690 early, so the global state is set correctly for this
1692 context_switch (ecs
->ptid
);
1694 /* Now figure out what to do with the result of the result. */
1695 handle_inferior_event (ecs
);
1697 if (!ecs
->wait_some_more
)
1699 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
1701 delete_step_thread_step_resume_breakpoint ();
1703 /* We may not find an inferior if this was a process exit. */
1704 if (inf
== NULL
|| inf
->stop_soon
== NO_STOP_QUIETLY
)
1707 if (target_has_execution
1708 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1709 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
1710 && ecs
->event_thread
->step_multi
1711 && ecs
->event_thread
->stop_step
)
1712 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
1714 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
1717 /* Revert thread and frame. */
1718 do_cleanups (old_chain
);
1720 /* If the inferior was in sync execution mode, and now isn't,
1721 restore the prompt. */
1722 if (was_sync
&& !sync_execution
)
1723 display_gdb_prompt (0);
1726 /* Prepare an execution control state for looping through a
1727 wait_for_inferior-type loop. */
1730 init_execution_control_state (struct execution_control_state
*ecs
)
1732 ecs
->random_signal
= 0;
1735 /* Clear context switchable stepping state. */
1738 init_thread_stepping_state (struct thread_info
*tss
)
1740 struct symtab_and_line sal
;
1742 tss
->stepping_over_breakpoint
= 0;
1743 tss
->step_after_step_resume_breakpoint
= 0;
1744 tss
->stepping_through_solib_after_catch
= 0;
1745 tss
->stepping_through_solib_catchpoints
= NULL
;
1747 sal
= find_pc_line (tss
->prev_pc
, 0);
1748 tss
->current_line
= sal
.line
;
1749 tss
->current_symtab
= sal
.symtab
;
1752 /* Return the cached copy of the last pid/waitstatus returned by
1753 target_wait()/deprecated_target_wait_hook(). The data is actually
1754 cached by handle_inferior_event(), which gets called immediately
1755 after target_wait()/deprecated_target_wait_hook(). */
1758 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
1760 *ptidp
= target_last_wait_ptid
;
1761 *status
= target_last_waitstatus
;
1765 nullify_last_target_wait_ptid (void)
1767 target_last_wait_ptid
= minus_one_ptid
;
1770 /* Switch thread contexts. */
1773 context_switch (ptid_t ptid
)
1777 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
1778 target_pid_to_str (inferior_ptid
));
1779 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
1780 target_pid_to_str (ptid
));
1783 switch_to_thread (ptid
);
1787 adjust_pc_after_break (struct execution_control_state
*ecs
)
1789 struct regcache
*regcache
;
1790 struct gdbarch
*gdbarch
;
1791 CORE_ADDR breakpoint_pc
;
1793 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
1794 we aren't, just return.
1796 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
1797 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
1798 implemented by software breakpoints should be handled through the normal
1801 NOTE drow/2004-01-31: On some targets, breakpoints may generate
1802 different signals (SIGILL or SIGEMT for instance), but it is less
1803 clear where the PC is pointing afterwards. It may not match
1804 gdbarch_decr_pc_after_break. I don't know any specific target that
1805 generates these signals at breakpoints (the code has been in GDB since at
1806 least 1992) so I can not guess how to handle them here.
1808 In earlier versions of GDB, a target with
1809 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
1810 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
1811 target with both of these set in GDB history, and it seems unlikely to be
1812 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
1814 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
1817 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1820 /* If this target does not decrement the PC after breakpoints, then
1821 we have nothing to do. */
1822 regcache
= get_thread_regcache (ecs
->ptid
);
1823 gdbarch
= get_regcache_arch (regcache
);
1824 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
1827 /* Find the location where (if we've hit a breakpoint) the
1828 breakpoint would be. */
1829 breakpoint_pc
= regcache_read_pc (regcache
)
1830 - gdbarch_decr_pc_after_break (gdbarch
);
1832 /* Check whether there actually is a software breakpoint inserted at
1835 If in non-stop mode, a race condition is possible where we've
1836 removed a breakpoint, but stop events for that breakpoint were
1837 already queued and arrive later. To suppress those spurious
1838 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
1839 and retire them after a number of stop events are reported. */
1840 if (software_breakpoint_inserted_here_p (breakpoint_pc
)
1841 || (non_stop
&& moribund_breakpoint_here_p (breakpoint_pc
)))
1843 /* When using hardware single-step, a SIGTRAP is reported for both
1844 a completed single-step and a software breakpoint. Need to
1845 differentiate between the two, as the latter needs adjusting
1846 but the former does not.
1848 The SIGTRAP can be due to a completed hardware single-step only if
1849 - we didn't insert software single-step breakpoints
1850 - the thread to be examined is still the current thread
1851 - this thread is currently being stepped
1853 If any of these events did not occur, we must have stopped due
1854 to hitting a software breakpoint, and have to back up to the
1857 As a special case, we could have hardware single-stepped a
1858 software breakpoint. In this case (prev_pc == breakpoint_pc),
1859 we also need to back up to the breakpoint address. */
1861 if (singlestep_breakpoints_inserted_p
1862 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
1863 || !currently_stepping (ecs
->event_thread
)
1864 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
1865 regcache_write_pc (regcache
, breakpoint_pc
);
1870 init_infwait_state (void)
1872 waiton_ptid
= pid_to_ptid (-1);
1873 infwait_state
= infwait_normal_state
;
1877 error_is_running (void)
1880 Cannot execute this command while the selected thread is running."));
1884 ensure_not_running (void)
1886 if (is_running (inferior_ptid
))
1887 error_is_running ();
1890 /* Given an execution control state that has been freshly filled in
1891 by an event from the inferior, figure out what it means and take
1892 appropriate action. */
1895 handle_inferior_event (struct execution_control_state
*ecs
)
1897 int sw_single_step_trap_p
= 0;
1898 int stopped_by_watchpoint
;
1899 int stepped_after_stopped_by_watchpoint
= 0;
1900 struct symtab_and_line stop_pc_sal
;
1901 enum stop_kind stop_soon
;
1903 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1904 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
1905 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
1907 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
1909 stop_soon
= inf
->stop_soon
;
1912 stop_soon
= NO_STOP_QUIETLY
;
1914 /* Cache the last pid/waitstatus. */
1915 target_last_wait_ptid
= ecs
->ptid
;
1916 target_last_waitstatus
= ecs
->ws
;
1918 /* Always clear state belonging to the previous time we stopped. */
1919 stop_stack_dummy
= 0;
1921 /* If it's a new process, add it to the thread database */
1923 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
1924 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
1925 && !in_thread_list (ecs
->ptid
));
1927 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1928 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
1929 add_thread (ecs
->ptid
);
1931 ecs
->event_thread
= find_thread_pid (ecs
->ptid
);
1933 /* Dependent on valid ECS->EVENT_THREAD. */
1934 adjust_pc_after_break (ecs
);
1936 /* Dependent on the current PC value modified by adjust_pc_after_break. */
1937 reinit_frame_cache ();
1939 if (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
1941 breakpoint_retire_moribund ();
1943 /* Mark the non-executing threads accordingly. */
1945 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
1946 || ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
1947 set_executing (pid_to_ptid (-1), 0);
1949 set_executing (ecs
->ptid
, 0);
1952 switch (infwait_state
)
1954 case infwait_thread_hop_state
:
1956 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
1957 /* Cancel the waiton_ptid. */
1958 waiton_ptid
= pid_to_ptid (-1);
1961 case infwait_normal_state
:
1963 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
1966 case infwait_step_watch_state
:
1968 fprintf_unfiltered (gdb_stdlog
,
1969 "infrun: infwait_step_watch_state\n");
1971 stepped_after_stopped_by_watchpoint
= 1;
1974 case infwait_nonstep_watch_state
:
1976 fprintf_unfiltered (gdb_stdlog
,
1977 "infrun: infwait_nonstep_watch_state\n");
1978 insert_breakpoints ();
1980 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1981 handle things like signals arriving and other things happening
1982 in combination correctly? */
1983 stepped_after_stopped_by_watchpoint
= 1;
1987 internal_error (__FILE__
, __LINE__
, _("bad switch"));
1989 infwait_state
= infwait_normal_state
;
1991 switch (ecs
->ws
.kind
)
1993 case TARGET_WAITKIND_LOADED
:
1995 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
1996 /* Ignore gracefully during startup of the inferior, as it might
1997 be the shell which has just loaded some objects, otherwise
1998 add the symbols for the newly loaded objects. Also ignore at
1999 the beginning of an attach or remote session; we will query
2000 the full list of libraries once the connection is
2002 if (stop_soon
== NO_STOP_QUIETLY
)
2004 /* Check for any newly added shared libraries if we're
2005 supposed to be adding them automatically. Switch
2006 terminal for any messages produced by
2007 breakpoint_re_set. */
2008 target_terminal_ours_for_output ();
2009 /* NOTE: cagney/2003-11-25: Make certain that the target
2010 stack's section table is kept up-to-date. Architectures,
2011 (e.g., PPC64), use the section table to perform
2012 operations such as address => section name and hence
2013 require the table to contain all sections (including
2014 those found in shared libraries). */
2015 /* NOTE: cagney/2003-11-25: Pass current_target and not
2016 exec_ops to SOLIB_ADD. This is because current GDB is
2017 only tooled to propagate section_table changes out from
2018 the "current_target" (see target_resize_to_sections), and
2019 not up from the exec stratum. This, of course, isn't
2020 right. "infrun.c" should only interact with the
2021 exec/process stratum, instead relying on the target stack
2022 to propagate relevant changes (stop, section table
2023 changed, ...) up to other layers. */
2025 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2027 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2029 target_terminal_inferior ();
2031 /* If requested, stop when the dynamic linker notifies
2032 gdb of events. This allows the user to get control
2033 and place breakpoints in initializer routines for
2034 dynamically loaded objects (among other things). */
2035 if (stop_on_solib_events
)
2037 stop_stepping (ecs
);
2041 /* NOTE drow/2007-05-11: This might be a good place to check
2042 for "catch load". */
2045 /* If we are skipping through a shell, or through shared library
2046 loading that we aren't interested in, resume the program. If
2047 we're running the program normally, also resume. But stop if
2048 we're attaching or setting up a remote connection. */
2049 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
2051 /* Loading of shared libraries might have changed breakpoint
2052 addresses. Make sure new breakpoints are inserted. */
2053 if (stop_soon
== NO_STOP_QUIETLY
2054 && !breakpoints_always_inserted_mode ())
2055 insert_breakpoints ();
2056 resume (0, TARGET_SIGNAL_0
);
2057 prepare_to_wait (ecs
);
2063 case TARGET_WAITKIND_SPURIOUS
:
2065 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
2066 resume (0, TARGET_SIGNAL_0
);
2067 prepare_to_wait (ecs
);
2070 case TARGET_WAITKIND_EXITED
:
2072 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
2073 target_terminal_ours (); /* Must do this before mourn anyway */
2074 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
2076 /* Record the exit code in the convenience variable $_exitcode, so
2077 that the user can inspect this again later. */
2078 set_internalvar (lookup_internalvar ("_exitcode"),
2079 value_from_longest (builtin_type_int32
,
2080 (LONGEST
) ecs
->ws
.value
.integer
));
2081 gdb_flush (gdb_stdout
);
2082 target_mourn_inferior ();
2083 singlestep_breakpoints_inserted_p
= 0;
2084 stop_print_frame
= 0;
2085 stop_stepping (ecs
);
2088 case TARGET_WAITKIND_SIGNALLED
:
2090 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2091 stop_print_frame
= 0;
2092 target_terminal_ours (); /* Must do this before mourn anyway */
2094 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2095 reach here unless the inferior is dead. However, for years
2096 target_kill() was called here, which hints that fatal signals aren't
2097 really fatal on some systems. If that's true, then some changes
2099 target_mourn_inferior ();
2101 print_stop_reason (SIGNAL_EXITED
, ecs
->ws
.value
.sig
);
2102 singlestep_breakpoints_inserted_p
= 0;
2103 stop_stepping (ecs
);
2106 /* The following are the only cases in which we keep going;
2107 the above cases end in a continue or goto. */
2108 case TARGET_WAITKIND_FORKED
:
2109 case TARGET_WAITKIND_VFORKED
:
2111 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2112 pending_follow
.kind
= ecs
->ws
.kind
;
2114 pending_follow
.fork_event
.parent_pid
= ecs
->ptid
;
2115 pending_follow
.fork_event
.child_pid
= ecs
->ws
.value
.related_pid
;
2117 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2119 context_switch (ecs
->ptid
);
2120 reinit_frame_cache ();
2123 stop_pc
= read_pc ();
2125 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2127 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2129 /* If no catchpoint triggered for this, then keep going. */
2130 if (ecs
->random_signal
)
2132 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2136 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2137 goto process_event_stop_test
;
2139 case TARGET_WAITKIND_EXECD
:
2141 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
2142 pending_follow
.execd_pathname
=
2143 savestring (ecs
->ws
.value
.execd_pathname
,
2144 strlen (ecs
->ws
.value
.execd_pathname
));
2146 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2148 context_switch (ecs
->ptid
);
2149 reinit_frame_cache ();
2152 stop_pc
= read_pc ();
2154 /* This causes the eventpoints and symbol table to be reset.
2155 Must do this now, before trying to determine whether to
2157 follow_exec (inferior_ptid
, pending_follow
.execd_pathname
);
2158 xfree (pending_follow
.execd_pathname
);
2160 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2161 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2163 /* If no catchpoint triggered for this, then keep going. */
2164 if (ecs
->random_signal
)
2166 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2170 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2171 goto process_event_stop_test
;
2173 /* Be careful not to try to gather much state about a thread
2174 that's in a syscall. It's frequently a losing proposition. */
2175 case TARGET_WAITKIND_SYSCALL_ENTRY
:
2177 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2178 resume (0, TARGET_SIGNAL_0
);
2179 prepare_to_wait (ecs
);
2182 /* Before examining the threads further, step this thread to
2183 get it entirely out of the syscall. (We get notice of the
2184 event when the thread is just on the verge of exiting a
2185 syscall. Stepping one instruction seems to get it back
2187 case TARGET_WAITKIND_SYSCALL_RETURN
:
2189 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2190 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
);
2191 prepare_to_wait (ecs
);
2194 case TARGET_WAITKIND_STOPPED
:
2196 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
2197 ecs
->event_thread
->stop_signal
= ecs
->ws
.value
.sig
;
2200 /* We had an event in the inferior, but we are not interested
2201 in handling it at this level. The lower layers have already
2202 done what needs to be done, if anything.
2204 One of the possible circumstances for this is when the
2205 inferior produces output for the console. The inferior has
2206 not stopped, and we are ignoring the event. Another possible
2207 circumstance is any event which the lower level knows will be
2208 reported multiple times without an intervening resume. */
2209 case TARGET_WAITKIND_IGNORE
:
2211 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2212 prepare_to_wait (ecs
);
2216 if (ecs
->new_thread_event
)
2219 /* Non-stop assumes that the target handles adding new threads
2220 to the thread list. */
2221 internal_error (__FILE__
, __LINE__
, "\
2222 targets should add new threads to the thread list themselves in non-stop mode.");
2224 /* We may want to consider not doing a resume here in order to
2225 give the user a chance to play with the new thread. It might
2226 be good to make that a user-settable option. */
2228 /* At this point, all threads are stopped (happens automatically
2229 in either the OS or the native code). Therefore we need to
2230 continue all threads in order to make progress. */
2232 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
2233 prepare_to_wait (ecs
);
2237 /* Do we need to clean up the state of a thread that has completed a
2238 displaced single-step? (Doing so usually affects the PC, so do
2239 it here, before we set stop_pc.) */
2240 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
2241 displaced_step_fixup (ecs
->ptid
, ecs
->event_thread
->stop_signal
);
2243 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2247 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = 0x%s\n",
2248 paddr_nz (stop_pc
));
2249 if (STOPPED_BY_WATCHPOINT (&ecs
->ws
))
2252 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
2254 if (target_stopped_data_address (¤t_target
, &addr
))
2255 fprintf_unfiltered (gdb_stdlog
,
2256 "infrun: stopped data address = 0x%s\n",
2259 fprintf_unfiltered (gdb_stdlog
,
2260 "infrun: (no data address available)\n");
2264 if (stepping_past_singlestep_breakpoint
)
2266 gdb_assert (singlestep_breakpoints_inserted_p
);
2267 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
2268 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
2270 stepping_past_singlestep_breakpoint
= 0;
2272 /* We've either finished single-stepping past the single-step
2273 breakpoint, or stopped for some other reason. It would be nice if
2274 we could tell, but we can't reliably. */
2275 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2278 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
2279 /* Pull the single step breakpoints out of the target. */
2280 remove_single_step_breakpoints ();
2281 singlestep_breakpoints_inserted_p
= 0;
2283 ecs
->random_signal
= 0;
2285 context_switch (saved_singlestep_ptid
);
2286 if (deprecated_context_hook
)
2287 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2289 resume (1, TARGET_SIGNAL_0
);
2290 prepare_to_wait (ecs
);
2295 stepping_past_singlestep_breakpoint
= 0;
2297 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
2299 /* In non-stop mode, there's never a deferred_step_ptid set. */
2300 gdb_assert (!non_stop
);
2302 /* If we stopped for some other reason than single-stepping, ignore
2303 the fact that we were supposed to switch back. */
2304 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2306 struct thread_info
*tp
;
2309 fprintf_unfiltered (gdb_stdlog
,
2310 "infrun: handling deferred step\n");
2312 /* Pull the single step breakpoints out of the target. */
2313 if (singlestep_breakpoints_inserted_p
)
2315 remove_single_step_breakpoints ();
2316 singlestep_breakpoints_inserted_p
= 0;
2319 /* Note: We do not call context_switch at this point, as the
2320 context is already set up for stepping the original thread. */
2321 switch_to_thread (deferred_step_ptid
);
2322 deferred_step_ptid
= null_ptid
;
2323 /* Suppress spurious "Switching to ..." message. */
2324 previous_inferior_ptid
= inferior_ptid
;
2326 resume (1, TARGET_SIGNAL_0
);
2327 prepare_to_wait (ecs
);
2331 deferred_step_ptid
= null_ptid
;
2334 /* See if a thread hit a thread-specific breakpoint that was meant for
2335 another thread. If so, then step that thread past the breakpoint,
2338 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2340 int thread_hop_needed
= 0;
2342 /* Check if a regular breakpoint has been hit before checking
2343 for a potential single step breakpoint. Otherwise, GDB will
2344 not see this breakpoint hit when stepping onto breakpoints. */
2345 if (regular_breakpoint_inserted_here_p (stop_pc
))
2347 ecs
->random_signal
= 0;
2348 if (!breakpoint_thread_match (stop_pc
, ecs
->ptid
))
2349 thread_hop_needed
= 1;
2351 else if (singlestep_breakpoints_inserted_p
)
2353 /* We have not context switched yet, so this should be true
2354 no matter which thread hit the singlestep breakpoint. */
2355 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
2357 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
2359 target_pid_to_str (ecs
->ptid
));
2361 ecs
->random_signal
= 0;
2362 /* The call to in_thread_list is necessary because PTIDs sometimes
2363 change when we go from single-threaded to multi-threaded. If
2364 the singlestep_ptid is still in the list, assume that it is
2365 really different from ecs->ptid. */
2366 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
2367 && in_thread_list (singlestep_ptid
))
2369 /* If the PC of the thread we were trying to single-step
2370 has changed, discard this event (which we were going
2371 to ignore anyway), and pretend we saw that thread
2372 trap. This prevents us continuously moving the
2373 single-step breakpoint forward, one instruction at a
2374 time. If the PC has changed, then the thread we were
2375 trying to single-step has trapped or been signalled,
2376 but the event has not been reported to GDB yet.
2378 There might be some cases where this loses signal
2379 information, if a signal has arrived at exactly the
2380 same time that the PC changed, but this is the best
2381 we can do with the information available. Perhaps we
2382 should arrange to report all events for all threads
2383 when they stop, or to re-poll the remote looking for
2384 this particular thread (i.e. temporarily enable
2387 CORE_ADDR new_singlestep_pc
2388 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
2390 if (new_singlestep_pc
!= singlestep_pc
)
2392 enum target_signal stop_signal
;
2395 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
2396 " but expected thread advanced also\n");
2398 /* The current context still belongs to
2399 singlestep_ptid. Don't swap here, since that's
2400 the context we want to use. Just fudge our
2401 state and continue. */
2402 stop_signal
= ecs
->event_thread
->stop_signal
;
2403 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2404 ecs
->ptid
= singlestep_ptid
;
2405 ecs
->event_thread
= find_thread_pid (ecs
->ptid
);
2406 ecs
->event_thread
->stop_signal
= stop_signal
;
2407 stop_pc
= new_singlestep_pc
;
2412 fprintf_unfiltered (gdb_stdlog
,
2413 "infrun: unexpected thread\n");
2415 thread_hop_needed
= 1;
2416 stepping_past_singlestep_breakpoint
= 1;
2417 saved_singlestep_ptid
= singlestep_ptid
;
2422 if (thread_hop_needed
)
2424 int remove_status
= 0;
2427 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
2429 /* Saw a breakpoint, but it was hit by the wrong thread.
2432 if (singlestep_breakpoints_inserted_p
)
2434 /* Pull the single step breakpoints out of the target. */
2435 remove_single_step_breakpoints ();
2436 singlestep_breakpoints_inserted_p
= 0;
2439 /* If the arch can displace step, don't remove the
2441 if (!use_displaced_stepping (current_gdbarch
))
2442 remove_status
= remove_breakpoints ();
2444 /* Did we fail to remove breakpoints? If so, try
2445 to set the PC past the bp. (There's at least
2446 one situation in which we can fail to remove
2447 the bp's: On HP-UX's that use ttrace, we can't
2448 change the address space of a vforking child
2449 process until the child exits (well, okay, not
2450 then either :-) or execs. */
2451 if (remove_status
!= 0)
2452 error (_("Cannot step over breakpoint hit in wrong thread"));
2455 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
2456 context_switch (ecs
->ptid
);
2460 /* Only need to require the next event from this
2461 thread in all-stop mode. */
2462 waiton_ptid
= ecs
->ptid
;
2463 infwait_state
= infwait_thread_hop_state
;
2466 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2468 registers_changed ();
2472 else if (singlestep_breakpoints_inserted_p
)
2474 sw_single_step_trap_p
= 1;
2475 ecs
->random_signal
= 0;
2479 ecs
->random_signal
= 1;
2481 /* See if something interesting happened to the non-current thread. If
2482 so, then switch to that thread. */
2483 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2486 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
2488 context_switch (ecs
->ptid
);
2490 if (deprecated_context_hook
)
2491 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2494 if (singlestep_breakpoints_inserted_p
)
2496 /* Pull the single step breakpoints out of the target. */
2497 remove_single_step_breakpoints ();
2498 singlestep_breakpoints_inserted_p
= 0;
2501 if (stepped_after_stopped_by_watchpoint
)
2502 stopped_by_watchpoint
= 0;
2504 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
2506 /* If necessary, step over this watchpoint. We'll be back to display
2508 if (stopped_by_watchpoint
2509 && (HAVE_STEPPABLE_WATCHPOINT
2510 || gdbarch_have_nonsteppable_watchpoint (current_gdbarch
)))
2512 /* At this point, we are stopped at an instruction which has
2513 attempted to write to a piece of memory under control of
2514 a watchpoint. The instruction hasn't actually executed
2515 yet. If we were to evaluate the watchpoint expression
2516 now, we would get the old value, and therefore no change
2517 would seem to have occurred.
2519 In order to make watchpoints work `right', we really need
2520 to complete the memory write, and then evaluate the
2521 watchpoint expression. We do this by single-stepping the
2524 It may not be necessary to disable the watchpoint to stop over
2525 it. For example, the PA can (with some kernel cooperation)
2526 single step over a watchpoint without disabling the watchpoint.
2528 It is far more common to need to disable a watchpoint to step
2529 the inferior over it. If we have non-steppable watchpoints,
2530 we must disable the current watchpoint; it's simplest to
2531 disable all watchpoints and breakpoints. */
2533 if (!HAVE_STEPPABLE_WATCHPOINT
)
2534 remove_breakpoints ();
2535 registers_changed ();
2536 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
); /* Single step */
2537 waiton_ptid
= ecs
->ptid
;
2538 if (HAVE_STEPPABLE_WATCHPOINT
)
2539 infwait_state
= infwait_step_watch_state
;
2541 infwait_state
= infwait_nonstep_watch_state
;
2542 prepare_to_wait (ecs
);
2546 ecs
->stop_func_start
= 0;
2547 ecs
->stop_func_end
= 0;
2548 ecs
->stop_func_name
= 0;
2549 /* Don't care about return value; stop_func_start and stop_func_name
2550 will both be 0 if it doesn't work. */
2551 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
2552 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
2553 ecs
->stop_func_start
2554 += gdbarch_deprecated_function_start_offset (current_gdbarch
);
2555 ecs
->event_thread
->stepping_over_breakpoint
= 0;
2556 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
2557 ecs
->event_thread
->stop_step
= 0;
2558 stop_print_frame
= 1;
2559 ecs
->random_signal
= 0;
2560 stopped_by_random_signal
= 0;
2562 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
2563 && ecs
->event_thread
->trap_expected
2564 && gdbarch_single_step_through_delay_p (current_gdbarch
)
2565 && currently_stepping (ecs
->event_thread
))
2567 /* We're trying to step off a breakpoint. Turns out that we're
2568 also on an instruction that needs to be stepped multiple
2569 times before it's been fully executing. E.g., architectures
2570 with a delay slot. It needs to be stepped twice, once for
2571 the instruction and once for the delay slot. */
2572 int step_through_delay
2573 = gdbarch_single_step_through_delay (current_gdbarch
,
2574 get_current_frame ());
2575 if (debug_infrun
&& step_through_delay
)
2576 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
2577 if (ecs
->event_thread
->step_range_end
== 0 && step_through_delay
)
2579 /* The user issued a continue when stopped at a breakpoint.
2580 Set up for another trap and get out of here. */
2581 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2585 else if (step_through_delay
)
2587 /* The user issued a step when stopped at a breakpoint.
2588 Maybe we should stop, maybe we should not - the delay
2589 slot *might* correspond to a line of source. In any
2590 case, don't decide that here, just set
2591 ecs->stepping_over_breakpoint, making sure we
2592 single-step again before breakpoints are re-inserted. */
2593 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2597 /* Look at the cause of the stop, and decide what to do.
2598 The alternatives are:
2599 1) stop_stepping and return; to really stop and return to the debugger,
2600 2) keep_going and return to start up again
2601 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
2602 3) set ecs->random_signal to 1, and the decision between 1 and 2
2603 will be made according to the signal handling tables. */
2605 /* First, distinguish signals caused by the debugger from signals
2606 that have to do with the program's own actions. Note that
2607 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
2608 on the operating system version. Here we detect when a SIGILL or
2609 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
2610 something similar for SIGSEGV, since a SIGSEGV will be generated
2611 when we're trying to execute a breakpoint instruction on a
2612 non-executable stack. This happens for call dummy breakpoints
2613 for architectures like SPARC that place call dummies on the
2616 If we're doing a displaced step past a breakpoint, then the
2617 breakpoint is always inserted at the original instruction;
2618 non-standard signals can't be explained by the breakpoint. */
2619 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
2620 || (! ecs
->event_thread
->trap_expected
2621 && breakpoint_inserted_here_p (stop_pc
)
2622 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_ILL
2623 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_SEGV
2624 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_EMT
))
2625 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2626 || stop_soon
== STOP_QUIETLY_REMOTE
)
2628 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
2631 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
2632 stop_print_frame
= 0;
2633 stop_stepping (ecs
);
2637 /* This is originated from start_remote(), start_inferior() and
2638 shared libraries hook functions. */
2639 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
2642 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
2643 stop_stepping (ecs
);
2647 /* This originates from attach_command(). We need to overwrite
2648 the stop_signal here, because some kernels don't ignore a
2649 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
2650 See more comments in inferior.h. On the other hand, if we
2651 get a non-SIGSTOP, report it to the user - assume the backend
2652 will handle the SIGSTOP if it should show up later.
2654 Also consider that the attach is complete when we see a
2655 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
2656 target extended-remote report it instead of a SIGSTOP
2657 (e.g. gdbserver). We already rely on SIGTRAP being our
2658 signal, so this is no exception. */
2659 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2660 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_STOP
2661 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
))
2663 stop_stepping (ecs
);
2664 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2668 /* See if there is a breakpoint at the current PC. */
2669 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2671 /* Following in case break condition called a
2673 stop_print_frame
= 1;
2675 /* NOTE: cagney/2003-03-29: These two checks for a random signal
2676 at one stage in the past included checks for an inferior
2677 function call's call dummy's return breakpoint. The original
2678 comment, that went with the test, read:
2680 ``End of a stack dummy. Some systems (e.g. Sony news) give
2681 another signal besides SIGTRAP, so check here as well as
2684 If someone ever tries to get call dummys on a
2685 non-executable stack to work (where the target would stop
2686 with something like a SIGSEGV), then those tests might need
2687 to be re-instated. Given, however, that the tests were only
2688 enabled when momentary breakpoints were not being used, I
2689 suspect that it won't be the case.
2691 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
2692 be necessary for call dummies on a non-executable stack on
2695 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2697 = !(bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
)
2698 || ecs
->event_thread
->trap_expected
2699 || (ecs
->event_thread
->step_range_end
2700 && ecs
->event_thread
->step_resume_breakpoint
== NULL
));
2703 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2704 if (!ecs
->random_signal
)
2705 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2709 /* When we reach this point, we've pretty much decided
2710 that the reason for stopping must've been a random
2711 (unexpected) signal. */
2714 ecs
->random_signal
= 1;
2716 process_event_stop_test
:
2717 /* For the program's own signals, act according to
2718 the signal handling tables. */
2720 if (ecs
->random_signal
)
2722 /* Signal not for debugging purposes. */
2726 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
2727 ecs
->event_thread
->stop_signal
);
2729 stopped_by_random_signal
= 1;
2731 if (signal_print
[ecs
->event_thread
->stop_signal
])
2734 target_terminal_ours_for_output ();
2735 print_stop_reason (SIGNAL_RECEIVED
, ecs
->event_thread
->stop_signal
);
2737 /* Always stop on signals if we're just gaining control of the
2739 if (stop_soon
!= NO_STOP_QUIETLY
2740 || signal_stop_state (ecs
->event_thread
->stop_signal
))
2742 stop_stepping (ecs
);
2745 /* If not going to stop, give terminal back
2746 if we took it away. */
2748 target_terminal_inferior ();
2750 /* Clear the signal if it should not be passed. */
2751 if (signal_program
[ecs
->event_thread
->stop_signal
] == 0)
2752 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2754 if (ecs
->event_thread
->prev_pc
== read_pc ()
2755 && ecs
->event_thread
->trap_expected
2756 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
2758 /* We were just starting a new sequence, attempting to
2759 single-step off of a breakpoint and expecting a SIGTRAP.
2760 Instead this signal arrives. This signal will take us out
2761 of the stepping range so GDB needs to remember to, when
2762 the signal handler returns, resume stepping off that
2764 /* To simplify things, "continue" is forced to use the same
2765 code paths as single-step - set a breakpoint at the
2766 signal return address and then, once hit, step off that
2769 fprintf_unfiltered (gdb_stdlog
,
2770 "infrun: signal arrived while stepping over "
2773 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2774 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
2779 if (ecs
->event_thread
->step_range_end
!= 0
2780 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_0
2781 && (ecs
->event_thread
->step_range_start
<= stop_pc
2782 && stop_pc
< ecs
->event_thread
->step_range_end
)
2783 && frame_id_eq (get_frame_id (get_current_frame ()),
2784 ecs
->event_thread
->step_frame_id
)
2785 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
2787 /* The inferior is about to take a signal that will take it
2788 out of the single step range. Set a breakpoint at the
2789 current PC (which is presumably where the signal handler
2790 will eventually return) and then allow the inferior to
2793 Note that this is only needed for a signal delivered
2794 while in the single-step range. Nested signals aren't a
2795 problem as they eventually all return. */
2797 fprintf_unfiltered (gdb_stdlog
,
2798 "infrun: signal may take us out of "
2799 "single-step range\n");
2801 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2806 /* Note: step_resume_breakpoint may be non-NULL. This occures
2807 when either there's a nested signal, or when there's a
2808 pending signal enabled just as the signal handler returns
2809 (leaving the inferior at the step-resume-breakpoint without
2810 actually executing it). Either way continue until the
2811 breakpoint is really hit. */
2816 /* Handle cases caused by hitting a breakpoint. */
2818 CORE_ADDR jmp_buf_pc
;
2819 struct bpstat_what what
;
2821 what
= bpstat_what (ecs
->event_thread
->stop_bpstat
);
2823 if (what
.call_dummy
)
2825 stop_stack_dummy
= 1;
2828 switch (what
.main_action
)
2830 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
2831 /* If we hit the breakpoint at longjmp while stepping, we
2832 install a momentary breakpoint at the target of the
2836 fprintf_unfiltered (gdb_stdlog
,
2837 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
2839 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2841 if (!gdbarch_get_longjmp_target_p (current_gdbarch
)
2842 || !gdbarch_get_longjmp_target (current_gdbarch
,
2843 get_current_frame (), &jmp_buf_pc
))
2846 fprintf_unfiltered (gdb_stdlog
, "\
2847 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
2852 /* We're going to replace the current step-resume breakpoint
2853 with a longjmp-resume breakpoint. */
2854 delete_step_resume_breakpoint (ecs
->event_thread
);
2856 /* Insert a breakpoint at resume address. */
2857 insert_longjmp_resume_breakpoint (jmp_buf_pc
);
2862 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
2864 fprintf_unfiltered (gdb_stdlog
,
2865 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
2867 gdb_assert (ecs
->event_thread
->step_resume_breakpoint
!= NULL
);
2868 delete_step_resume_breakpoint (ecs
->event_thread
);
2870 ecs
->event_thread
->stop_step
= 1;
2871 print_stop_reason (END_STEPPING_RANGE
, 0);
2872 stop_stepping (ecs
);
2875 case BPSTAT_WHAT_SINGLE
:
2877 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
2878 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2879 /* Still need to check other stuff, at least the case
2880 where we are stepping and step out of the right range. */
2883 case BPSTAT_WHAT_STOP_NOISY
:
2885 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
2886 stop_print_frame
= 1;
2888 /* We are about to nuke the step_resume_breakpointt via the
2889 cleanup chain, so no need to worry about it here. */
2891 stop_stepping (ecs
);
2894 case BPSTAT_WHAT_STOP_SILENT
:
2896 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
2897 stop_print_frame
= 0;
2899 /* We are about to nuke the step_resume_breakpoin via the
2900 cleanup chain, so no need to worry about it here. */
2902 stop_stepping (ecs
);
2905 case BPSTAT_WHAT_STEP_RESUME
:
2907 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
2909 delete_step_resume_breakpoint (ecs
->event_thread
);
2910 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
2912 /* Back when the step-resume breakpoint was inserted, we
2913 were trying to single-step off a breakpoint. Go back
2915 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
2916 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2922 case BPSTAT_WHAT_CHECK_SHLIBS
:
2923 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
:
2926 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
2928 /* Check for any newly added shared libraries if we're
2929 supposed to be adding them automatically. Switch
2930 terminal for any messages produced by
2931 breakpoint_re_set. */
2932 target_terminal_ours_for_output ();
2933 /* NOTE: cagney/2003-11-25: Make certain that the target
2934 stack's section table is kept up-to-date. Architectures,
2935 (e.g., PPC64), use the section table to perform
2936 operations such as address => section name and hence
2937 require the table to contain all sections (including
2938 those found in shared libraries). */
2939 /* NOTE: cagney/2003-11-25: Pass current_target and not
2940 exec_ops to SOLIB_ADD. This is because current GDB is
2941 only tooled to propagate section_table changes out from
2942 the "current_target" (see target_resize_to_sections), and
2943 not up from the exec stratum. This, of course, isn't
2944 right. "infrun.c" should only interact with the
2945 exec/process stratum, instead relying on the target stack
2946 to propagate relevant changes (stop, section table
2947 changed, ...) up to other layers. */
2949 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2951 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2953 target_terminal_inferior ();
2955 /* If requested, stop when the dynamic linker notifies
2956 gdb of events. This allows the user to get control
2957 and place breakpoints in initializer routines for
2958 dynamically loaded objects (among other things). */
2959 if (stop_on_solib_events
|| stop_stack_dummy
)
2961 stop_stepping (ecs
);
2965 /* If we stopped due to an explicit catchpoint, then the
2966 (see above) call to SOLIB_ADD pulled in any symbols
2967 from a newly-loaded library, if appropriate.
2969 We do want the inferior to stop, but not where it is
2970 now, which is in the dynamic linker callback. Rather,
2971 we would like it stop in the user's program, just after
2972 the call that caused this catchpoint to trigger. That
2973 gives the user a more useful vantage from which to
2974 examine their program's state. */
2975 else if (what
.main_action
2976 == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
)
2978 /* ??rehrauer: If I could figure out how to get the
2979 right return PC from here, we could just set a temp
2980 breakpoint and resume. I'm not sure we can without
2981 cracking open the dld's shared libraries and sniffing
2982 their unwind tables and text/data ranges, and that's
2983 not a terribly portable notion.
2985 Until that time, we must step the inferior out of the
2986 dld callback, and also out of the dld itself (and any
2987 code or stubs in libdld.sl, such as "shl_load" and
2988 friends) until we reach non-dld code. At that point,
2989 we can stop stepping. */
2990 bpstat_get_triggered_catchpoints (ecs
->event_thread
->stop_bpstat
,
2993 stepping_through_solib_catchpoints
);
2994 ecs
->event_thread
->stepping_through_solib_after_catch
= 1;
2996 /* Be sure to lift all breakpoints, so the inferior does
2997 actually step past this point... */
2998 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3003 /* We want to step over this breakpoint, then keep going. */
3004 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3010 case BPSTAT_WHAT_LAST
:
3011 /* Not a real code, but listed here to shut up gcc -Wall. */
3013 case BPSTAT_WHAT_KEEP_CHECKING
:
3018 /* We come here if we hit a breakpoint but should not
3019 stop for it. Possibly we also were stepping
3020 and should stop for that. So fall through and
3021 test for stepping. But, if not stepping,
3024 /* Are we stepping to get the inferior out of the dynamic linker's
3025 hook (and possibly the dld itself) after catching a shlib
3027 if (ecs
->event_thread
->stepping_through_solib_after_catch
)
3029 #if defined(SOLIB_ADD)
3030 /* Have we reached our destination? If not, keep going. */
3031 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
3034 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
3035 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3041 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
3042 /* Else, stop and report the catchpoint(s) whose triggering
3043 caused us to begin stepping. */
3044 ecs
->event_thread
->stepping_through_solib_after_catch
= 0;
3045 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
3046 ecs
->event_thread
->stop_bpstat
3047 = bpstat_copy (ecs
->event_thread
->stepping_through_solib_catchpoints
);
3048 bpstat_clear (&ecs
->event_thread
->stepping_through_solib_catchpoints
);
3049 stop_print_frame
= 1;
3050 stop_stepping (ecs
);
3054 if (ecs
->event_thread
->step_resume_breakpoint
)
3057 fprintf_unfiltered (gdb_stdlog
,
3058 "infrun: step-resume breakpoint is inserted\n");
3060 /* Having a step-resume breakpoint overrides anything
3061 else having to do with stepping commands until
3062 that breakpoint is reached. */
3067 if (ecs
->event_thread
->step_range_end
== 0)
3070 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
3071 /* Likewise if we aren't even stepping. */
3076 /* If stepping through a line, keep going if still within it.
3078 Note that step_range_end is the address of the first instruction
3079 beyond the step range, and NOT the address of the last instruction
3081 if (stop_pc
>= ecs
->event_thread
->step_range_start
3082 && stop_pc
< ecs
->event_thread
->step_range_end
)
3085 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping inside range [0x%s-0x%s]\n",
3086 paddr_nz (ecs
->event_thread
->step_range_start
),
3087 paddr_nz (ecs
->event_thread
->step_range_end
));
3092 /* We stepped out of the stepping range. */
3094 /* If we are stepping at the source level and entered the runtime
3095 loader dynamic symbol resolution code, we keep on single stepping
3096 until we exit the run time loader code and reach the callee's
3098 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3099 && in_solib_dynsym_resolve_code (stop_pc
))
3101 CORE_ADDR pc_after_resolver
=
3102 gdbarch_skip_solib_resolver (current_gdbarch
, stop_pc
);
3105 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
3107 if (pc_after_resolver
)
3109 /* Set up a step-resume breakpoint at the address
3110 indicated by SKIP_SOLIB_RESOLVER. */
3111 struct symtab_and_line sr_sal
;
3113 sr_sal
.pc
= pc_after_resolver
;
3115 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3122 if (ecs
->event_thread
->step_range_end
!= 1
3123 && (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3124 || ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3125 && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME
)
3128 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
3129 /* The inferior, while doing a "step" or "next", has ended up in
3130 a signal trampoline (either by a signal being delivered or by
3131 the signal handler returning). Just single-step until the
3132 inferior leaves the trampoline (either by calling the handler
3138 /* Check for subroutine calls. The check for the current frame
3139 equalling the step ID is not necessary - the check of the
3140 previous frame's ID is sufficient - but it is a common case and
3141 cheaper than checking the previous frame's ID.
3143 NOTE: frame_id_eq will never report two invalid frame IDs as
3144 being equal, so to get into this block, both the current and
3145 previous frame must have valid frame IDs. */
3146 if (!frame_id_eq (get_frame_id (get_current_frame ()),
3147 ecs
->event_thread
->step_frame_id
)
3148 && frame_id_eq (frame_unwind_id (get_current_frame ()),
3149 ecs
->event_thread
->step_frame_id
))
3151 CORE_ADDR real_stop_pc
;
3154 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
3156 if ((ecs
->event_thread
->step_over_calls
== STEP_OVER_NONE
)
3157 || ((ecs
->event_thread
->step_range_end
== 1)
3158 && in_prologue (ecs
->event_thread
->prev_pc
,
3159 ecs
->stop_func_start
)))
3161 /* I presume that step_over_calls is only 0 when we're
3162 supposed to be stepping at the assembly language level
3163 ("stepi"). Just stop. */
3164 /* Also, maybe we just did a "nexti" inside a prolog, so we
3165 thought it was a subroutine call but it was not. Stop as
3167 ecs
->event_thread
->stop_step
= 1;
3168 print_stop_reason (END_STEPPING_RANGE
, 0);
3169 stop_stepping (ecs
);
3173 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3175 /* We're doing a "next", set a breakpoint at callee's return
3176 address (the address at which the caller will
3178 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3183 /* If we are in a function call trampoline (a stub between the
3184 calling routine and the real function), locate the real
3185 function. That's what tells us (a) whether we want to step
3186 into it at all, and (b) what prologue we want to run to the
3187 end of, if we do step into it. */
3188 real_stop_pc
= skip_language_trampoline (get_current_frame (), stop_pc
);
3189 if (real_stop_pc
== 0)
3190 real_stop_pc
= gdbarch_skip_trampoline_code
3191 (current_gdbarch
, get_current_frame (), stop_pc
);
3192 if (real_stop_pc
!= 0)
3193 ecs
->stop_func_start
= real_stop_pc
;
3195 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
3197 struct symtab_and_line sr_sal
;
3199 sr_sal
.pc
= ecs
->stop_func_start
;
3201 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3206 /* If we have line number information for the function we are
3207 thinking of stepping into, step into it.
3209 If there are several symtabs at that PC (e.g. with include
3210 files), just want to know whether *any* of them have line
3211 numbers. find_pc_line handles this. */
3213 struct symtab_and_line tmp_sal
;
3215 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3216 if (tmp_sal
.line
!= 0)
3218 step_into_function (ecs
);
3223 /* If we have no line number and the step-stop-if-no-debug is
3224 set, we stop the step so that the user has a chance to switch
3225 in assembly mode. */
3226 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3227 && step_stop_if_no_debug
)
3229 ecs
->event_thread
->stop_step
= 1;
3230 print_stop_reason (END_STEPPING_RANGE
, 0);
3231 stop_stepping (ecs
);
3235 /* Set a breakpoint at callee's return address (the address at
3236 which the caller will resume). */
3237 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3242 /* If we're in the return path from a shared library trampoline,
3243 we want to proceed through the trampoline when stepping. */
3244 if (gdbarch_in_solib_return_trampoline (current_gdbarch
,
3245 stop_pc
, ecs
->stop_func_name
))
3247 /* Determine where this trampoline returns. */
3248 CORE_ADDR real_stop_pc
;
3249 real_stop_pc
= gdbarch_skip_trampoline_code
3250 (current_gdbarch
, get_current_frame (), stop_pc
);
3253 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
3255 /* Only proceed through if we know where it's going. */
3258 /* And put the step-breakpoint there and go until there. */
3259 struct symtab_and_line sr_sal
;
3261 init_sal (&sr_sal
); /* initialize to zeroes */
3262 sr_sal
.pc
= real_stop_pc
;
3263 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3265 /* Do not specify what the fp should be when we stop since
3266 on some machines the prologue is where the new fp value
3268 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3270 /* Restart without fiddling with the step ranges or
3277 stop_pc_sal
= find_pc_line (stop_pc
, 0);
3279 /* NOTE: tausq/2004-05-24: This if block used to be done before all
3280 the trampoline processing logic, however, there are some trampolines
3281 that have no names, so we should do trampoline handling first. */
3282 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3283 && ecs
->stop_func_name
== NULL
3284 && stop_pc_sal
.line
== 0)
3287 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
3289 /* The inferior just stepped into, or returned to, an
3290 undebuggable function (where there is no debugging information
3291 and no line number corresponding to the address where the
3292 inferior stopped). Since we want to skip this kind of code,
3293 we keep going until the inferior returns from this
3294 function - unless the user has asked us not to (via
3295 set step-mode) or we no longer know how to get back
3296 to the call site. */
3297 if (step_stop_if_no_debug
3298 || !frame_id_p (frame_unwind_id (get_current_frame ())))
3300 /* If we have no line number and the step-stop-if-no-debug
3301 is set, we stop the step so that the user has a chance to
3302 switch in assembly mode. */
3303 ecs
->event_thread
->stop_step
= 1;
3304 print_stop_reason (END_STEPPING_RANGE
, 0);
3305 stop_stepping (ecs
);
3310 /* Set a breakpoint at callee's return address (the address
3311 at which the caller will resume). */
3312 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3318 if (ecs
->event_thread
->step_range_end
== 1)
3320 /* It is stepi or nexti. We always want to stop stepping after
3323 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
3324 ecs
->event_thread
->stop_step
= 1;
3325 print_stop_reason (END_STEPPING_RANGE
, 0);
3326 stop_stepping (ecs
);
3330 if (stop_pc_sal
.line
== 0)
3332 /* We have no line number information. That means to stop
3333 stepping (does this always happen right after one instruction,
3334 when we do "s" in a function with no line numbers,
3335 or can this happen as a result of a return or longjmp?). */
3337 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
3338 ecs
->event_thread
->stop_step
= 1;
3339 print_stop_reason (END_STEPPING_RANGE
, 0);
3340 stop_stepping (ecs
);
3344 if ((stop_pc
== stop_pc_sal
.pc
)
3345 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
3346 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
3348 /* We are at the start of a different line. So stop. Note that
3349 we don't stop if we step into the middle of a different line.
3350 That is said to make things like for (;;) statements work
3353 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
3354 ecs
->event_thread
->stop_step
= 1;
3355 print_stop_reason (END_STEPPING_RANGE
, 0);
3356 stop_stepping (ecs
);
3360 /* We aren't done stepping.
3362 Optimize by setting the stepping range to the line.
3363 (We might not be in the original line, but if we entered a
3364 new line in mid-statement, we continue stepping. This makes
3365 things like for(;;) statements work better.) */
3367 ecs
->event_thread
->step_range_start
= stop_pc_sal
.pc
;
3368 ecs
->event_thread
->step_range_end
= stop_pc_sal
.end
;
3369 ecs
->event_thread
->step_frame_id
= get_frame_id (get_current_frame ());
3370 ecs
->event_thread
->current_line
= stop_pc_sal
.line
;
3371 ecs
->event_thread
->current_symtab
= stop_pc_sal
.symtab
;
3374 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
3378 /* Are we in the middle of stepping? */
3381 currently_stepping (struct thread_info
*tp
)
3383 return (((tp
->step_range_end
&& tp
->step_resume_breakpoint
== NULL
)
3384 || tp
->trap_expected
)
3385 || tp
->stepping_through_solib_after_catch
3386 || bpstat_should_step ());
3389 /* Subroutine call with source code we should not step over. Do step
3390 to the first line of code in it. */
3393 step_into_function (struct execution_control_state
*ecs
)
3396 struct symtab_and_line stop_func_sal
, sr_sal
;
3398 s
= find_pc_symtab (stop_pc
);
3399 if (s
&& s
->language
!= language_asm
)
3400 ecs
->stop_func_start
= gdbarch_skip_prologue
3401 (current_gdbarch
, ecs
->stop_func_start
);
3403 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3404 /* Use the step_resume_break to step until the end of the prologue,
3405 even if that involves jumps (as it seems to on the vax under
3407 /* If the prologue ends in the middle of a source line, continue to
3408 the end of that source line (if it is still within the function).
3409 Otherwise, just go to end of prologue. */
3410 if (stop_func_sal
.end
3411 && stop_func_sal
.pc
!= ecs
->stop_func_start
3412 && stop_func_sal
.end
< ecs
->stop_func_end
)
3413 ecs
->stop_func_start
= stop_func_sal
.end
;
3415 /* Architectures which require breakpoint adjustment might not be able
3416 to place a breakpoint at the computed address. If so, the test
3417 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
3418 ecs->stop_func_start to an address at which a breakpoint may be
3419 legitimately placed.
3421 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
3422 made, GDB will enter an infinite loop when stepping through
3423 optimized code consisting of VLIW instructions which contain
3424 subinstructions corresponding to different source lines. On
3425 FR-V, it's not permitted to place a breakpoint on any but the
3426 first subinstruction of a VLIW instruction. When a breakpoint is
3427 set, GDB will adjust the breakpoint address to the beginning of
3428 the VLIW instruction. Thus, we need to make the corresponding
3429 adjustment here when computing the stop address. */
3431 if (gdbarch_adjust_breakpoint_address_p (current_gdbarch
))
3433 ecs
->stop_func_start
3434 = gdbarch_adjust_breakpoint_address (current_gdbarch
,
3435 ecs
->stop_func_start
);
3438 if (ecs
->stop_func_start
== stop_pc
)
3440 /* We are already there: stop now. */
3441 ecs
->event_thread
->stop_step
= 1;
3442 print_stop_reason (END_STEPPING_RANGE
, 0);
3443 stop_stepping (ecs
);
3448 /* Put the step-breakpoint there and go until there. */
3449 init_sal (&sr_sal
); /* initialize to zeroes */
3450 sr_sal
.pc
= ecs
->stop_func_start
;
3451 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
3453 /* Do not specify what the fp should be when we stop since on
3454 some machines the prologue is where the new fp value is
3456 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3458 /* And make sure stepping stops right away then. */
3459 ecs
->event_thread
->step_range_end
= ecs
->event_thread
->step_range_start
;
3464 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
3465 This is used to both functions and to skip over code. */
3468 insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
3469 struct frame_id sr_id
)
3471 /* There should never be more than one step-resume or longjmp-resume
3472 breakpoint per thread, so we should never be setting a new
3473 step_resume_breakpoint when one is already active. */
3474 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
3477 fprintf_unfiltered (gdb_stdlog
,
3478 "infrun: inserting step-resume breakpoint at 0x%s\n",
3479 paddr_nz (sr_sal
.pc
));
3481 inferior_thread ()->step_resume_breakpoint
3482 = set_momentary_breakpoint (sr_sal
, sr_id
, bp_step_resume
);
3485 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
3486 to skip a potential signal handler.
3488 This is called with the interrupted function's frame. The signal
3489 handler, when it returns, will resume the interrupted function at
3493 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
3495 struct symtab_and_line sr_sal
;
3497 gdb_assert (return_frame
!= NULL
);
3498 init_sal (&sr_sal
); /* initialize to zeros */
3500 sr_sal
.pc
= gdbarch_addr_bits_remove
3501 (current_gdbarch
, get_frame_pc (return_frame
));
3502 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3504 insert_step_resume_breakpoint_at_sal (sr_sal
, get_frame_id (return_frame
));
3507 /* Similar to insert_step_resume_breakpoint_at_frame, except
3508 but a breakpoint at the previous frame's PC. This is used to
3509 skip a function after stepping into it (for "next" or if the called
3510 function has no debugging information).
3512 The current function has almost always been reached by single
3513 stepping a call or return instruction. NEXT_FRAME belongs to the
3514 current function, and the breakpoint will be set at the caller's
3517 This is a separate function rather than reusing
3518 insert_step_resume_breakpoint_at_frame in order to avoid
3519 get_prev_frame, which may stop prematurely (see the implementation
3520 of frame_unwind_id for an example). */
3523 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
3525 struct symtab_and_line sr_sal
;
3527 /* We shouldn't have gotten here if we don't know where the call site
3529 gdb_assert (frame_id_p (frame_unwind_id (next_frame
)));
3531 init_sal (&sr_sal
); /* initialize to zeros */
3533 sr_sal
.pc
= gdbarch_addr_bits_remove
3534 (current_gdbarch
, frame_pc_unwind (next_frame
));
3535 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3537 insert_step_resume_breakpoint_at_sal (sr_sal
, frame_unwind_id (next_frame
));
3540 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
3541 new breakpoint at the target of a jmp_buf. The handling of
3542 longjmp-resume uses the same mechanisms used for handling
3543 "step-resume" breakpoints. */
3546 insert_longjmp_resume_breakpoint (CORE_ADDR pc
)
3548 /* There should never be more than one step-resume or longjmp-resume
3549 breakpoint per thread, so we should never be setting a new
3550 longjmp_resume_breakpoint when one is already active. */
3551 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
3554 fprintf_unfiltered (gdb_stdlog
,
3555 "infrun: inserting longjmp-resume breakpoint at 0x%s\n",
3558 inferior_thread ()->step_resume_breakpoint
=
3559 set_momentary_breakpoint_at_pc (pc
, bp_longjmp_resume
);
3563 stop_stepping (struct execution_control_state
*ecs
)
3566 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
3568 /* Let callers know we don't want to wait for the inferior anymore. */
3569 ecs
->wait_some_more
= 0;
3572 /* This function handles various cases where we need to continue
3573 waiting for the inferior. */
3574 /* (Used to be the keep_going: label in the old wait_for_inferior) */
3577 keep_going (struct execution_control_state
*ecs
)
3579 /* Save the pc before execution, to compare with pc after stop. */
3580 ecs
->event_thread
->prev_pc
= read_pc (); /* Might have been DECR_AFTER_BREAK */
3582 /* If we did not do break;, it means we should keep running the
3583 inferior and not return to debugger. */
3585 if (ecs
->event_thread
->trap_expected
3586 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
3588 /* We took a signal (which we are supposed to pass through to
3589 the inferior, else we'd not get here) and we haven't yet
3590 gotten our trap. Simply continue. */
3591 resume (currently_stepping (ecs
->event_thread
),
3592 ecs
->event_thread
->stop_signal
);
3596 /* Either the trap was not expected, but we are continuing
3597 anyway (the user asked that this signal be passed to the
3600 The signal was SIGTRAP, e.g. it was our signal, but we
3601 decided we should resume from it.
3603 We're going to run this baby now!
3605 Note that insert_breakpoints won't try to re-insert
3606 already inserted breakpoints. Therefore, we don't
3607 care if breakpoints were already inserted, or not. */
3609 if (ecs
->event_thread
->stepping_over_breakpoint
)
3611 if (! use_displaced_stepping (current_gdbarch
))
3612 /* Since we can't do a displaced step, we have to remove
3613 the breakpoint while we step it. To keep things
3614 simple, we remove them all. */
3615 remove_breakpoints ();
3619 struct gdb_exception e
;
3620 /* Stop stepping when inserting breakpoints
3622 TRY_CATCH (e
, RETURN_MASK_ERROR
)
3624 insert_breakpoints ();
3628 stop_stepping (ecs
);
3633 ecs
->event_thread
->trap_expected
= ecs
->event_thread
->stepping_over_breakpoint
;
3635 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3636 specifies that such a signal should be delivered to the
3639 Typically, this would occure when a user is debugging a
3640 target monitor on a simulator: the target monitor sets a
3641 breakpoint; the simulator encounters this break-point and
3642 halts the simulation handing control to GDB; GDB, noteing
3643 that the break-point isn't valid, returns control back to the
3644 simulator; the simulator then delivers the hardware
3645 equivalent of a SIGNAL_TRAP to the program being debugged. */
3647 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3648 && !signal_program
[ecs
->event_thread
->stop_signal
])
3649 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3651 resume (currently_stepping (ecs
->event_thread
),
3652 ecs
->event_thread
->stop_signal
);
3655 prepare_to_wait (ecs
);
3658 /* This function normally comes after a resume, before
3659 handle_inferior_event exits. It takes care of any last bits of
3660 housekeeping, and sets the all-important wait_some_more flag. */
3663 prepare_to_wait (struct execution_control_state
*ecs
)
3666 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
3667 if (infwait_state
== infwait_normal_state
)
3669 overlay_cache_invalid
= 1;
3671 /* We have to invalidate the registers BEFORE calling
3672 target_wait because they can be loaded from the target while
3673 in target_wait. This makes remote debugging a bit more
3674 efficient for those targets that provide critical registers
3675 as part of their normal status mechanism. */
3677 registers_changed ();
3678 waiton_ptid
= pid_to_ptid (-1);
3680 /* This is the old end of the while loop. Let everybody know we
3681 want to wait for the inferior some more and get called again
3683 ecs
->wait_some_more
= 1;
3686 /* Print why the inferior has stopped. We always print something when
3687 the inferior exits, or receives a signal. The rest of the cases are
3688 dealt with later on in normal_stop() and print_it_typical(). Ideally
3689 there should be a call to this function from handle_inferior_event()
3690 each time stop_stepping() is called.*/
3692 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
3694 switch (stop_reason
)
3696 case END_STEPPING_RANGE
:
3697 /* We are done with a step/next/si/ni command. */
3698 /* For now print nothing. */
3699 /* Print a message only if not in the middle of doing a "step n"
3700 operation for n > 1 */
3701 if (!inferior_thread ()->step_multi
3702 || !inferior_thread ()->stop_step
)
3703 if (ui_out_is_mi_like_p (uiout
))
3706 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
3709 /* The inferior was terminated by a signal. */
3710 annotate_signalled ();
3711 if (ui_out_is_mi_like_p (uiout
))
3714 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
3715 ui_out_text (uiout
, "\nProgram terminated with signal ");
3716 annotate_signal_name ();
3717 ui_out_field_string (uiout
, "signal-name",
3718 target_signal_to_name (stop_info
));
3719 annotate_signal_name_end ();
3720 ui_out_text (uiout
, ", ");
3721 annotate_signal_string ();
3722 ui_out_field_string (uiout
, "signal-meaning",
3723 target_signal_to_string (stop_info
));
3724 annotate_signal_string_end ();
3725 ui_out_text (uiout
, ".\n");
3726 ui_out_text (uiout
, "The program no longer exists.\n");
3729 /* The inferior program is finished. */
3730 annotate_exited (stop_info
);
3733 if (ui_out_is_mi_like_p (uiout
))
3734 ui_out_field_string (uiout
, "reason",
3735 async_reason_lookup (EXEC_ASYNC_EXITED
));
3736 ui_out_text (uiout
, "\nProgram exited with code ");
3737 ui_out_field_fmt (uiout
, "exit-code", "0%o",
3738 (unsigned int) stop_info
);
3739 ui_out_text (uiout
, ".\n");
3743 if (ui_out_is_mi_like_p (uiout
))
3746 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
3747 ui_out_text (uiout
, "\nProgram exited normally.\n");
3749 /* Support the --return-child-result option. */
3750 return_child_result_value
= stop_info
;
3752 case SIGNAL_RECEIVED
:
3753 /* Signal received. The signal table tells us to print about
3756 ui_out_text (uiout
, "\nProgram received signal ");
3757 annotate_signal_name ();
3758 if (ui_out_is_mi_like_p (uiout
))
3760 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
3761 ui_out_field_string (uiout
, "signal-name",
3762 target_signal_to_name (stop_info
));
3763 annotate_signal_name_end ();
3764 ui_out_text (uiout
, ", ");
3765 annotate_signal_string ();
3766 ui_out_field_string (uiout
, "signal-meaning",
3767 target_signal_to_string (stop_info
));
3768 annotate_signal_string_end ();
3769 ui_out_text (uiout
, ".\n");
3772 internal_error (__FILE__
, __LINE__
,
3773 _("print_stop_reason: unrecognized enum value"));
3779 /* Here to return control to GDB when the inferior stops for real.
3780 Print appropriate messages, remove breakpoints, give terminal our modes.
3782 STOP_PRINT_FRAME nonzero means print the executing frame
3783 (pc, function, args, file, line number and line text).
3784 BREAKPOINTS_FAILED nonzero means stop was due to error
3785 attempting to insert breakpoints. */
3790 struct target_waitstatus last
;
3793 get_last_target_status (&last_ptid
, &last
);
3795 /* In non-stop mode, we don't want GDB to switch threads behind the
3796 user's back, to avoid races where the user is typing a command to
3797 apply to thread x, but GDB switches to thread y before the user
3798 finishes entering the command. */
3800 /* As with the notification of thread events, we want to delay
3801 notifying the user that we've switched thread context until
3802 the inferior actually stops.
3804 There's no point in saying anything if the inferior has exited.
3805 Note that SIGNALLED here means "exited with a signal", not
3806 "received a signal". */
3808 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
3809 && target_has_execution
3810 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3811 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3813 target_terminal_ours_for_output ();
3814 printf_filtered (_("[Switching to %s]\n"),
3815 target_pid_to_str (inferior_ptid
));
3816 annotate_thread_changed ();
3817 previous_inferior_ptid
= inferior_ptid
;
3820 /* NOTE drow/2004-01-17: Is this still necessary? */
3821 /* Make sure that the current_frame's pc is correct. This
3822 is a correction for setting up the frame info before doing
3823 gdbarch_decr_pc_after_break */
3824 if (target_has_execution
)
3825 /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
3826 gdbarch_decr_pc_after_break, the program counter can change. Ask the
3827 frame code to check for this and sort out any resultant mess.
3828 gdbarch_decr_pc_after_break needs to just go away. */
3829 deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
3831 if (!breakpoints_always_inserted_mode () && target_has_execution
)
3833 if (remove_breakpoints ())
3835 target_terminal_ours_for_output ();
3836 printf_filtered (_("\
3837 Cannot remove breakpoints because program is no longer writable.\n\
3838 It might be running in another process.\n\
3839 Further execution is probably impossible.\n"));
3843 /* If an auto-display called a function and that got a signal,
3844 delete that auto-display to avoid an infinite recursion. */
3846 if (stopped_by_random_signal
)
3847 disable_current_display ();
3849 /* Don't print a message if in the middle of doing a "step n"
3850 operation for n > 1 */
3851 if (target_has_execution
3852 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3853 && last
.kind
!= TARGET_WAITKIND_EXITED
3854 && inferior_thread ()->step_multi
3855 && inferior_thread ()->stop_step
)
3858 target_terminal_ours ();
3860 /* Set the current source location. This will also happen if we
3861 display the frame below, but the current SAL will be incorrect
3862 during a user hook-stop function. */
3863 if (target_has_stack
&& !stop_stack_dummy
)
3864 set_current_sal_from_frame (get_current_frame (), 1);
3866 if (!target_has_stack
)
3869 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
3870 || last
.kind
== TARGET_WAITKIND_EXITED
)
3873 /* Select innermost stack frame - i.e., current frame is frame 0,
3874 and current location is based on that.
3875 Don't do this on return from a stack dummy routine,
3876 or if the program has exited. */
3878 if (!stop_stack_dummy
)
3880 select_frame (get_current_frame ());
3882 /* Print current location without a level number, if
3883 we have changed functions or hit a breakpoint.
3884 Print source line if we have one.
3885 bpstat_print() contains the logic deciding in detail
3886 what to print, based on the event(s) that just occurred. */
3888 /* If --batch-silent is enabled then there's no need to print the current
3889 source location, and to try risks causing an error message about
3890 missing source files. */
3891 if (stop_print_frame
&& !batch_silent
)
3895 int do_frame_printing
= 1;
3896 struct thread_info
*tp
= inferior_thread ();
3898 bpstat_ret
= bpstat_print (tp
->stop_bpstat
);
3902 /* If we had hit a shared library event breakpoint,
3903 bpstat_print would print out this message. If we hit
3904 an OS-level shared library event, do the same
3906 if (last
.kind
== TARGET_WAITKIND_LOADED
)
3908 printf_filtered (_("Stopped due to shared library event\n"));
3909 source_flag
= SRC_LINE
; /* something bogus */
3910 do_frame_printing
= 0;
3914 /* FIXME: cagney/2002-12-01: Given that a frame ID does
3915 (or should) carry around the function and does (or
3916 should) use that when doing a frame comparison. */
3918 && frame_id_eq (tp
->step_frame_id
,
3919 get_frame_id (get_current_frame ()))
3920 && step_start_function
== find_pc_function (stop_pc
))
3921 source_flag
= SRC_LINE
; /* finished step, just print source line */
3923 source_flag
= SRC_AND_LOC
; /* print location and source line */
3925 case PRINT_SRC_AND_LOC
:
3926 source_flag
= SRC_AND_LOC
; /* print location and source line */
3928 case PRINT_SRC_ONLY
:
3929 source_flag
= SRC_LINE
;
3932 source_flag
= SRC_LINE
; /* something bogus */
3933 do_frame_printing
= 0;
3936 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
3939 if (ui_out_is_mi_like_p (uiout
))
3942 ui_out_field_int (uiout
, "thread-id",
3943 pid_to_thread_id (inferior_ptid
));
3946 struct cleanup
*back_to
= make_cleanup_ui_out_list_begin_end
3947 (uiout
, "stopped-threads");
3948 ui_out_field_int (uiout
, NULL
,
3949 pid_to_thread_id (inferior_ptid
));
3950 do_cleanups (back_to
);
3953 ui_out_field_string (uiout
, "stopped-threads", "all");
3955 /* The behavior of this routine with respect to the source
3957 SRC_LINE: Print only source line
3958 LOCATION: Print only location
3959 SRC_AND_LOC: Print location and source line */
3960 if (do_frame_printing
)
3961 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
3963 /* Display the auto-display expressions. */
3968 /* Save the function value return registers, if we care.
3969 We might be about to restore their previous contents. */
3970 if (inferior_thread ()->proceed_to_finish
)
3972 /* This should not be necessary. */
3974 regcache_xfree (stop_registers
);
3976 /* NB: The copy goes through to the target picking up the value of
3977 all the registers. */
3978 stop_registers
= regcache_dup (get_current_regcache ());
3981 if (stop_stack_dummy
)
3983 /* Pop the empty frame that contains the stack dummy. POP_FRAME
3984 ends with a setting of the current frame, so we can use that
3986 frame_pop (get_current_frame ());
3987 /* Set stop_pc to what it was before we called the function.
3988 Can't rely on restore_inferior_status because that only gets
3989 called if we don't stop in the called function. */
3990 stop_pc
= read_pc ();
3991 select_frame (get_current_frame ());
3995 annotate_stopped ();
3996 if (!suppress_stop_observer
3997 && !(target_has_execution
3998 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3999 && last
.kind
!= TARGET_WAITKIND_EXITED
4000 && inferior_thread ()->step_multi
))
4002 if (!ptid_equal (inferior_ptid
, null_ptid
))
4003 observer_notify_normal_stop (inferior_thread ()->stop_bpstat
);
4005 observer_notify_normal_stop (NULL
);
4007 if (target_has_execution
4008 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
4009 && last
.kind
!= TARGET_WAITKIND_EXITED
)
4011 /* Delete the breakpoint we stopped at, if it wants to be deleted.
4012 Delete any breakpoint that is to be deleted at the next stop. */
4013 breakpoint_auto_delete (inferior_thread ()->stop_bpstat
);
4016 set_running (pid_to_ptid (-1), 0);
4018 set_running (inferior_ptid
, 0);
4021 /* Look up the hook_stop and run it (CLI internally handles problem
4022 of stop_command's pre-hook not existing). */
4024 catch_errors (hook_stop_stub
, stop_command
,
4025 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
4030 hook_stop_stub (void *cmd
)
4032 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
4037 signal_stop_state (int signo
)
4039 return signal_stop
[signo
];
4043 signal_print_state (int signo
)
4045 return signal_print
[signo
];
4049 signal_pass_state (int signo
)
4051 return signal_program
[signo
];
4055 signal_stop_update (int signo
, int state
)
4057 int ret
= signal_stop
[signo
];
4058 signal_stop
[signo
] = state
;
4063 signal_print_update (int signo
, int state
)
4065 int ret
= signal_print
[signo
];
4066 signal_print
[signo
] = state
;
4071 signal_pass_update (int signo
, int state
)
4073 int ret
= signal_program
[signo
];
4074 signal_program
[signo
] = state
;
4079 sig_print_header (void)
4081 printf_filtered (_("\
4082 Signal Stop\tPrint\tPass to program\tDescription\n"));
4086 sig_print_info (enum target_signal oursig
)
4088 char *name
= target_signal_to_name (oursig
);
4089 int name_padding
= 13 - strlen (name
);
4091 if (name_padding
<= 0)
4094 printf_filtered ("%s", name
);
4095 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
4096 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
4097 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
4098 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
4099 printf_filtered ("%s\n", target_signal_to_string (oursig
));
4102 /* Specify how various signals in the inferior should be handled. */
4105 handle_command (char *args
, int from_tty
)
4108 int digits
, wordlen
;
4109 int sigfirst
, signum
, siglast
;
4110 enum target_signal oursig
;
4113 unsigned char *sigs
;
4114 struct cleanup
*old_chain
;
4118 error_no_arg (_("signal to handle"));
4121 /* Allocate and zero an array of flags for which signals to handle. */
4123 nsigs
= (int) TARGET_SIGNAL_LAST
;
4124 sigs
= (unsigned char *) alloca (nsigs
);
4125 memset (sigs
, 0, nsigs
);
4127 /* Break the command line up into args. */
4129 argv
= gdb_buildargv (args
);
4130 old_chain
= make_cleanup_freeargv (argv
);
4132 /* Walk through the args, looking for signal oursigs, signal names, and
4133 actions. Signal numbers and signal names may be interspersed with
4134 actions, with the actions being performed for all signals cumulatively
4135 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
4137 while (*argv
!= NULL
)
4139 wordlen
= strlen (*argv
);
4140 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
4144 sigfirst
= siglast
= -1;
4146 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
4148 /* Apply action to all signals except those used by the
4149 debugger. Silently skip those. */
4152 siglast
= nsigs
- 1;
4154 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
4156 SET_SIGS (nsigs
, sigs
, signal_stop
);
4157 SET_SIGS (nsigs
, sigs
, signal_print
);
4159 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
4161 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4163 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
4165 SET_SIGS (nsigs
, sigs
, signal_print
);
4167 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
4169 SET_SIGS (nsigs
, sigs
, signal_program
);
4171 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
4173 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4175 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
4177 SET_SIGS (nsigs
, sigs
, signal_program
);
4179 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
4181 UNSET_SIGS (nsigs
, sigs
, signal_print
);
4182 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4184 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
4186 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4188 else if (digits
> 0)
4190 /* It is numeric. The numeric signal refers to our own
4191 internal signal numbering from target.h, not to host/target
4192 signal number. This is a feature; users really should be
4193 using symbolic names anyway, and the common ones like
4194 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
4196 sigfirst
= siglast
= (int)
4197 target_signal_from_command (atoi (*argv
));
4198 if ((*argv
)[digits
] == '-')
4201 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
4203 if (sigfirst
> siglast
)
4205 /* Bet he didn't figure we'd think of this case... */
4213 oursig
= target_signal_from_name (*argv
);
4214 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
4216 sigfirst
= siglast
= (int) oursig
;
4220 /* Not a number and not a recognized flag word => complain. */
4221 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
4225 /* If any signal numbers or symbol names were found, set flags for
4226 which signals to apply actions to. */
4228 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
4230 switch ((enum target_signal
) signum
)
4232 case TARGET_SIGNAL_TRAP
:
4233 case TARGET_SIGNAL_INT
:
4234 if (!allsigs
&& !sigs
[signum
])
4236 if (query ("%s is used by the debugger.\n\
4237 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal
) signum
)))
4243 printf_unfiltered (_("Not confirmed, unchanged.\n"));
4244 gdb_flush (gdb_stdout
);
4248 case TARGET_SIGNAL_0
:
4249 case TARGET_SIGNAL_DEFAULT
:
4250 case TARGET_SIGNAL_UNKNOWN
:
4251 /* Make sure that "all" doesn't print these. */
4262 target_notice_signals (inferior_ptid
);
4266 /* Show the results. */
4267 sig_print_header ();
4268 for (signum
= 0; signum
< nsigs
; signum
++)
4272 sig_print_info (signum
);
4277 do_cleanups (old_chain
);
4281 xdb_handle_command (char *args
, int from_tty
)
4284 struct cleanup
*old_chain
;
4287 error_no_arg (_("xdb command"));
4289 /* Break the command line up into args. */
4291 argv
= gdb_buildargv (args
);
4292 old_chain
= make_cleanup_freeargv (argv
);
4293 if (argv
[1] != (char *) NULL
)
4298 bufLen
= strlen (argv
[0]) + 20;
4299 argBuf
= (char *) xmalloc (bufLen
);
4303 enum target_signal oursig
;
4305 oursig
= target_signal_from_name (argv
[0]);
4306 memset (argBuf
, 0, bufLen
);
4307 if (strcmp (argv
[1], "Q") == 0)
4308 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4311 if (strcmp (argv
[1], "s") == 0)
4313 if (!signal_stop
[oursig
])
4314 sprintf (argBuf
, "%s %s", argv
[0], "stop");
4316 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
4318 else if (strcmp (argv
[1], "i") == 0)
4320 if (!signal_program
[oursig
])
4321 sprintf (argBuf
, "%s %s", argv
[0], "pass");
4323 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
4325 else if (strcmp (argv
[1], "r") == 0)
4327 if (!signal_print
[oursig
])
4328 sprintf (argBuf
, "%s %s", argv
[0], "print");
4330 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4336 handle_command (argBuf
, from_tty
);
4338 printf_filtered (_("Invalid signal handling flag.\n"));
4343 do_cleanups (old_chain
);
4346 /* Print current contents of the tables set by the handle command.
4347 It is possible we should just be printing signals actually used
4348 by the current target (but for things to work right when switching
4349 targets, all signals should be in the signal tables). */
4352 signals_info (char *signum_exp
, int from_tty
)
4354 enum target_signal oursig
;
4355 sig_print_header ();
4359 /* First see if this is a symbol name. */
4360 oursig
= target_signal_from_name (signum_exp
);
4361 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
4363 /* No, try numeric. */
4365 target_signal_from_command (parse_and_eval_long (signum_exp
));
4367 sig_print_info (oursig
);
4371 printf_filtered ("\n");
4372 /* These ugly casts brought to you by the native VAX compiler. */
4373 for (oursig
= TARGET_SIGNAL_FIRST
;
4374 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
4375 oursig
= (enum target_signal
) ((int) oursig
+ 1))
4379 if (oursig
!= TARGET_SIGNAL_UNKNOWN
4380 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
4381 sig_print_info (oursig
);
4384 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
4387 struct inferior_status
4389 enum target_signal stop_signal
;
4393 int stop_stack_dummy
;
4394 int stopped_by_random_signal
;
4395 int stepping_over_breakpoint
;
4396 CORE_ADDR step_range_start
;
4397 CORE_ADDR step_range_end
;
4398 struct frame_id step_frame_id
;
4399 enum step_over_calls_kind step_over_calls
;
4400 CORE_ADDR step_resume_break_address
;
4401 int stop_after_trap
;
4404 /* These are here because if call_function_by_hand has written some
4405 registers and then decides to call error(), we better not have changed
4407 struct regcache
*registers
;
4409 /* A frame unique identifier. */
4410 struct frame_id selected_frame_id
;
4412 int breakpoint_proceeded
;
4413 int restore_stack_info
;
4414 int proceed_to_finish
;
4418 write_inferior_status_register (struct inferior_status
*inf_status
, int regno
,
4421 int size
= register_size (current_gdbarch
, regno
);
4422 void *buf
= alloca (size
);
4423 store_signed_integer (buf
, size
, val
);
4424 regcache_raw_write (inf_status
->registers
, regno
, buf
);
4427 /* Save all of the information associated with the inferior<==>gdb
4428 connection. INF_STATUS is a pointer to a "struct inferior_status"
4429 (defined in inferior.h). */
4431 struct inferior_status
*
4432 save_inferior_status (int restore_stack_info
)
4434 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
4435 struct thread_info
*tp
= inferior_thread ();
4436 struct inferior
*inf
= current_inferior ();
4438 inf_status
->stop_signal
= tp
->stop_signal
;
4439 inf_status
->stop_pc
= stop_pc
;
4440 inf_status
->stop_step
= tp
->stop_step
;
4441 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
4442 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
4443 inf_status
->stepping_over_breakpoint
= tp
->trap_expected
;
4444 inf_status
->step_range_start
= tp
->step_range_start
;
4445 inf_status
->step_range_end
= tp
->step_range_end
;
4446 inf_status
->step_frame_id
= tp
->step_frame_id
;
4447 inf_status
->step_over_calls
= tp
->step_over_calls
;
4448 inf_status
->stop_after_trap
= stop_after_trap
;
4449 inf_status
->stop_soon
= inf
->stop_soon
;
4450 /* Save original bpstat chain here; replace it with copy of chain.
4451 If caller's caller is walking the chain, they'll be happier if we
4452 hand them back the original chain when restore_inferior_status is
4454 inf_status
->stop_bpstat
= tp
->stop_bpstat
;
4455 tp
->stop_bpstat
= bpstat_copy (tp
->stop_bpstat
);
4456 inf_status
->breakpoint_proceeded
= breakpoint_proceeded
;
4457 inf_status
->restore_stack_info
= restore_stack_info
;
4458 inf_status
->proceed_to_finish
= tp
->proceed_to_finish
;
4460 inf_status
->registers
= regcache_dup (get_current_regcache ());
4462 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
4467 restore_selected_frame (void *args
)
4469 struct frame_id
*fid
= (struct frame_id
*) args
;
4470 struct frame_info
*frame
;
4472 frame
= frame_find_by_id (*fid
);
4474 /* If inf_status->selected_frame_id is NULL, there was no previously
4478 warning (_("Unable to restore previously selected frame."));
4482 select_frame (frame
);
4488 restore_inferior_status (struct inferior_status
*inf_status
)
4490 struct thread_info
*tp
= inferior_thread ();
4491 struct inferior
*inf
= current_inferior ();
4493 tp
->stop_signal
= inf_status
->stop_signal
;
4494 stop_pc
= inf_status
->stop_pc
;
4495 tp
->stop_step
= inf_status
->stop_step
;
4496 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
4497 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
4498 tp
->trap_expected
= inf_status
->stepping_over_breakpoint
;
4499 tp
->step_range_start
= inf_status
->step_range_start
;
4500 tp
->step_range_end
= inf_status
->step_range_end
;
4501 tp
->step_frame_id
= inf_status
->step_frame_id
;
4502 tp
->step_over_calls
= inf_status
->step_over_calls
;
4503 stop_after_trap
= inf_status
->stop_after_trap
;
4504 inf
->stop_soon
= inf_status
->stop_soon
;
4505 bpstat_clear (&tp
->stop_bpstat
);
4506 tp
->stop_bpstat
= inf_status
->stop_bpstat
;
4507 breakpoint_proceeded
= inf_status
->breakpoint_proceeded
;
4508 tp
->proceed_to_finish
= inf_status
->proceed_to_finish
;
4510 /* The inferior can be gone if the user types "print exit(0)"
4511 (and perhaps other times). */
4512 if (target_has_execution
)
4513 /* NB: The register write goes through to the target. */
4514 regcache_cpy (get_current_regcache (), inf_status
->registers
);
4515 regcache_xfree (inf_status
->registers
);
4517 /* FIXME: If we are being called after stopping in a function which
4518 is called from gdb, we should not be trying to restore the
4519 selected frame; it just prints a spurious error message (The
4520 message is useful, however, in detecting bugs in gdb (like if gdb
4521 clobbers the stack)). In fact, should we be restoring the
4522 inferior status at all in that case? . */
4524 if (target_has_stack
&& inf_status
->restore_stack_info
)
4526 /* The point of catch_errors is that if the stack is clobbered,
4527 walking the stack might encounter a garbage pointer and
4528 error() trying to dereference it. */
4530 (restore_selected_frame
, &inf_status
->selected_frame_id
,
4531 "Unable to restore previously selected frame:\n",
4532 RETURN_MASK_ERROR
) == 0)
4533 /* Error in restoring the selected frame. Select the innermost
4535 select_frame (get_current_frame ());
4543 do_restore_inferior_status_cleanup (void *sts
)
4545 restore_inferior_status (sts
);
4549 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
4551 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
4555 discard_inferior_status (struct inferior_status
*inf_status
)
4557 /* See save_inferior_status for info on stop_bpstat. */
4558 bpstat_clear (&inf_status
->stop_bpstat
);
4559 regcache_xfree (inf_status
->registers
);
4564 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
4566 struct target_waitstatus last
;
4569 get_last_target_status (&last_ptid
, &last
);
4571 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
4574 if (!ptid_equal (last_ptid
, pid
))
4577 *child_pid
= last
.value
.related_pid
;
4582 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
4584 struct target_waitstatus last
;
4587 get_last_target_status (&last_ptid
, &last
);
4589 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
4592 if (!ptid_equal (last_ptid
, pid
))
4595 *child_pid
= last
.value
.related_pid
;
4600 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
4602 struct target_waitstatus last
;
4605 get_last_target_status (&last_ptid
, &last
);
4607 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
4610 if (!ptid_equal (last_ptid
, pid
))
4613 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
4617 /* Oft used ptids */
4619 ptid_t minus_one_ptid
;
4621 /* Create a ptid given the necessary PID, LWP, and TID components. */
4624 ptid_build (int pid
, long lwp
, long tid
)
4634 /* Create a ptid from just a pid. */
4637 pid_to_ptid (int pid
)
4639 return ptid_build (pid
, 0, 0);
4642 /* Fetch the pid (process id) component from a ptid. */
4645 ptid_get_pid (ptid_t ptid
)
4650 /* Fetch the lwp (lightweight process) component from a ptid. */
4653 ptid_get_lwp (ptid_t ptid
)
4658 /* Fetch the tid (thread id) component from a ptid. */
4661 ptid_get_tid (ptid_t ptid
)
4666 /* ptid_equal() is used to test equality of two ptids. */
4669 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
4671 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
4672 && ptid1
.tid
== ptid2
.tid
);
4675 /* restore_inferior_ptid() will be used by the cleanup machinery
4676 to restore the inferior_ptid value saved in a call to
4677 save_inferior_ptid(). */
4680 restore_inferior_ptid (void *arg
)
4682 ptid_t
*saved_ptid_ptr
= arg
;
4683 inferior_ptid
= *saved_ptid_ptr
;
4687 /* Save the value of inferior_ptid so that it may be restored by a
4688 later call to do_cleanups(). Returns the struct cleanup pointer
4689 needed for later doing the cleanup. */
4692 save_inferior_ptid (void)
4694 ptid_t
*saved_ptid_ptr
;
4696 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
4697 *saved_ptid_ptr
= inferior_ptid
;
4698 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
4703 static int non_stop_1
= 0;
4706 set_non_stop (char *args
, int from_tty
,
4707 struct cmd_list_element
*c
)
4709 if (target_has_execution
)
4711 non_stop_1
= non_stop
;
4712 error (_("Cannot change this setting while the inferior is running."));
4715 non_stop
= non_stop_1
;
4719 show_non_stop (struct ui_file
*file
, int from_tty
,
4720 struct cmd_list_element
*c
, const char *value
)
4722 fprintf_filtered (file
,
4723 _("Controlling the inferior in non-stop mode is %s.\n"),
4729 _initialize_infrun (void)
4733 struct cmd_list_element
*c
;
4735 add_info ("signals", signals_info
, _("\
4736 What debugger does when program gets various signals.\n\
4737 Specify a signal as argument to print info on that signal only."));
4738 add_info_alias ("handle", "signals", 0);
4740 add_com ("handle", class_run
, handle_command
, _("\
4741 Specify how to handle a signal.\n\
4742 Args are signals and actions to apply to those signals.\n\
4743 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4744 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4745 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4746 The special arg \"all\" is recognized to mean all signals except those\n\
4747 used by the debugger, typically SIGTRAP and SIGINT.\n\
4748 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4749 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4750 Stop means reenter debugger if this signal happens (implies print).\n\
4751 Print means print a message if this signal happens.\n\
4752 Pass means let program see this signal; otherwise program doesn't know.\n\
4753 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4754 Pass and Stop may be combined."));
4757 add_com ("lz", class_info
, signals_info
, _("\
4758 What debugger does when program gets various signals.\n\
4759 Specify a signal as argument to print info on that signal only."));
4760 add_com ("z", class_run
, xdb_handle_command
, _("\
4761 Specify how to handle a signal.\n\
4762 Args are signals and actions to apply to those signals.\n\
4763 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4764 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4765 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4766 The special arg \"all\" is recognized to mean all signals except those\n\
4767 used by the debugger, typically SIGTRAP and SIGINT.\n\
4768 Recognized actions include \"s\" (toggles between stop and nostop), \n\
4769 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4770 nopass), \"Q\" (noprint)\n\
4771 Stop means reenter debugger if this signal happens (implies print).\n\
4772 Print means print a message if this signal happens.\n\
4773 Pass means let program see this signal; otherwise program doesn't know.\n\
4774 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4775 Pass and Stop may be combined."));
4779 stop_command
= add_cmd ("stop", class_obscure
,
4780 not_just_help_class_command
, _("\
4781 There is no `stop' command, but you can set a hook on `stop'.\n\
4782 This allows you to set a list of commands to be run each time execution\n\
4783 of the program stops."), &cmdlist
);
4785 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
4786 Set inferior debugging."), _("\
4787 Show inferior debugging."), _("\
4788 When non-zero, inferior specific debugging is enabled."),
4791 &setdebuglist
, &showdebuglist
);
4793 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
4794 Set displaced stepping debugging."), _("\
4795 Show displaced stepping debugging."), _("\
4796 When non-zero, displaced stepping specific debugging is enabled."),
4798 show_debug_displaced
,
4799 &setdebuglist
, &showdebuglist
);
4801 add_setshow_boolean_cmd ("non-stop", no_class
,
4803 Set whether gdb controls the inferior in non-stop mode."), _("\
4804 Show whether gdb controls the inferior in non-stop mode."), _("\
4805 When debugging a multi-threaded program and this setting is\n\
4806 off (the default, also called all-stop mode), when one thread stops\n\
4807 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
4808 all other threads in the program while you interact with the thread of\n\
4809 interest. When you continue or step a thread, you can allow the other\n\
4810 threads to run, or have them remain stopped, but while you inspect any\n\
4811 thread's state, all threads stop.\n\
4813 In non-stop mode, when one thread stops, other threads can continue\n\
4814 to run freely. You'll be able to step each thread independently,\n\
4815 leave it stopped or free to run as needed."),
4821 numsigs
= (int) TARGET_SIGNAL_LAST
;
4822 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
4823 signal_print
= (unsigned char *)
4824 xmalloc (sizeof (signal_print
[0]) * numsigs
);
4825 signal_program
= (unsigned char *)
4826 xmalloc (sizeof (signal_program
[0]) * numsigs
);
4827 for (i
= 0; i
< numsigs
; i
++)
4830 signal_print
[i
] = 1;
4831 signal_program
[i
] = 1;
4834 /* Signals caused by debugger's own actions
4835 should not be given to the program afterwards. */
4836 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
4837 signal_program
[TARGET_SIGNAL_INT
] = 0;
4839 /* Signals that are not errors should not normally enter the debugger. */
4840 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
4841 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
4842 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
4843 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
4844 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
4845 signal_print
[TARGET_SIGNAL_PROF
] = 0;
4846 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
4847 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
4848 signal_stop
[TARGET_SIGNAL_IO
] = 0;
4849 signal_print
[TARGET_SIGNAL_IO
] = 0;
4850 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
4851 signal_print
[TARGET_SIGNAL_POLL
] = 0;
4852 signal_stop
[TARGET_SIGNAL_URG
] = 0;
4853 signal_print
[TARGET_SIGNAL_URG
] = 0;
4854 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
4855 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
4857 /* These signals are used internally by user-level thread
4858 implementations. (See signal(5) on Solaris.) Like the above
4859 signals, a healthy program receives and handles them as part of
4860 its normal operation. */
4861 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
4862 signal_print
[TARGET_SIGNAL_LWP
] = 0;
4863 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
4864 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
4865 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
4866 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
4868 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
4869 &stop_on_solib_events
, _("\
4870 Set stopping for shared library events."), _("\
4871 Show stopping for shared library events."), _("\
4872 If nonzero, gdb will give control to the user when the dynamic linker\n\
4873 notifies gdb of shared library events. The most common event of interest\n\
4874 to the user would be loading/unloading of a new library."),
4876 show_stop_on_solib_events
,
4877 &setlist
, &showlist
);
4879 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
4880 follow_fork_mode_kind_names
,
4881 &follow_fork_mode_string
, _("\
4882 Set debugger response to a program call of fork or vfork."), _("\
4883 Show debugger response to a program call of fork or vfork."), _("\
4884 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4885 parent - the original process is debugged after a fork\n\
4886 child - the new process is debugged after a fork\n\
4887 The unfollowed process will continue to run.\n\
4888 By default, the debugger will follow the parent process."),
4890 show_follow_fork_mode_string
,
4891 &setlist
, &showlist
);
4893 add_setshow_enum_cmd ("scheduler-locking", class_run
,
4894 scheduler_enums
, &scheduler_mode
, _("\
4895 Set mode for locking scheduler during execution."), _("\
4896 Show mode for locking scheduler during execution."), _("\
4897 off == no locking (threads may preempt at any time)\n\
4898 on == full locking (no thread except the current thread may run)\n\
4899 step == scheduler locked during every single-step operation.\n\
4900 In this mode, no other thread may run during a step command.\n\
4901 Other threads may run while stepping over a function call ('next')."),
4902 set_schedlock_func
, /* traps on target vector */
4903 show_scheduler_mode
,
4904 &setlist
, &showlist
);
4906 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
4907 Set mode of the step operation."), _("\
4908 Show mode of the step operation."), _("\
4909 When set, doing a step over a function without debug line information\n\
4910 will stop at the first instruction of that function. Otherwise, the\n\
4911 function is skipped and the step command stops at a different source line."),
4913 show_step_stop_if_no_debug
,
4914 &setlist
, &showlist
);
4916 add_setshow_boolean_cmd ("can-use-displaced-stepping", class_maintenance
,
4917 &can_use_displaced_stepping
, _("\
4918 Set debugger's willingness to use displaced stepping."), _("\
4919 Show debugger's willingness to use displaced stepping."), _("\
4920 If zero, gdb will not use displaced stepping to step over\n\
4921 breakpoints, even if such is supported by the target."),
4923 show_can_use_displaced_stepping
,
4924 &maintenance_set_cmdlist
,
4925 &maintenance_show_cmdlist
);
4927 /* ptid initializations */
4928 null_ptid
= ptid_build (0, 0, 0);
4929 minus_one_ptid
= ptid_build (-1, 0, 0);
4930 inferior_ptid
= null_ptid
;
4931 target_last_wait_ptid
= minus_one_ptid
;
4932 displaced_step_ptid
= null_ptid
;
4934 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);