1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
5 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
6 2008 Free Software Foundation, Inc.
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "gdb_string.h"
29 #include "exceptions.h"
30 #include "breakpoint.h"
34 #include "cli/cli-script.h"
36 #include "gdbthread.h"
49 #include "gdb_assert.h"
50 #include "mi/mi-common.h"
51 #include "event-top.h"
53 /* Prototypes for local functions */
55 static void signals_info (char *, int);
57 static void handle_command (char *, int);
59 static void sig_print_info (enum target_signal
);
61 static void sig_print_header (void);
63 static void resume_cleanups (void *);
65 static int hook_stop_stub (void *);
67 static int restore_selected_frame (void *);
69 static void build_infrun (void);
71 static int follow_fork (void);
73 static void set_schedlock_func (char *args
, int from_tty
,
74 struct cmd_list_element
*c
);
76 static int currently_stepping (struct thread_info
*tp
);
78 static void xdb_handle_command (char *args
, int from_tty
);
80 static int prepare_to_proceed (int);
82 void _initialize_infrun (void);
84 /* When set, stop the 'step' command if we enter a function which has
85 no line number information. The normal behavior is that we step
86 over such function. */
87 int step_stop_if_no_debug
= 0;
89 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
90 struct cmd_list_element
*c
, const char *value
)
92 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
95 /* In asynchronous mode, but simulating synchronous execution. */
97 int sync_execution
= 0;
99 /* wait_for_inferior and normal_stop use this to notify the user
100 when the inferior stopped in a different thread than it had been
103 static ptid_t previous_inferior_ptid
;
105 int debug_displaced
= 0;
107 show_debug_displaced (struct ui_file
*file
, int from_tty
,
108 struct cmd_list_element
*c
, const char *value
)
110 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
113 static int debug_infrun
= 0;
115 show_debug_infrun (struct ui_file
*file
, int from_tty
,
116 struct cmd_list_element
*c
, const char *value
)
118 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
121 /* If the program uses ELF-style shared libraries, then calls to
122 functions in shared libraries go through stubs, which live in a
123 table called the PLT (Procedure Linkage Table). The first time the
124 function is called, the stub sends control to the dynamic linker,
125 which looks up the function's real address, patches the stub so
126 that future calls will go directly to the function, and then passes
127 control to the function.
129 If we are stepping at the source level, we don't want to see any of
130 this --- we just want to skip over the stub and the dynamic linker.
131 The simple approach is to single-step until control leaves the
134 However, on some systems (e.g., Red Hat's 5.2 distribution) the
135 dynamic linker calls functions in the shared C library, so you
136 can't tell from the PC alone whether the dynamic linker is still
137 running. In this case, we use a step-resume breakpoint to get us
138 past the dynamic linker, as if we were using "next" to step over a
141 in_solib_dynsym_resolve_code() says whether we're in the dynamic
142 linker code or not. Normally, this means we single-step. However,
143 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
144 address where we can place a step-resume breakpoint to get past the
145 linker's symbol resolution function.
147 in_solib_dynsym_resolve_code() can generally be implemented in a
148 pretty portable way, by comparing the PC against the address ranges
149 of the dynamic linker's sections.
151 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
152 it depends on internal details of the dynamic linker. It's usually
153 not too hard to figure out where to put a breakpoint, but it
154 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
155 sanity checking. If it can't figure things out, returning zero and
156 getting the (possibly confusing) stepping behavior is better than
157 signalling an error, which will obscure the change in the
160 /* This function returns TRUE if pc is the address of an instruction
161 that lies within the dynamic linker (such as the event hook, or the
164 This function must be used only when a dynamic linker event has
165 been caught, and the inferior is being stepped out of the hook, or
166 undefined results are guaranteed. */
168 #ifndef SOLIB_IN_DYNAMIC_LINKER
169 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
173 /* Convert the #defines into values. This is temporary until wfi control
174 flow is completely sorted out. */
176 #ifndef CANNOT_STEP_HW_WATCHPOINTS
177 #define CANNOT_STEP_HW_WATCHPOINTS 0
179 #undef CANNOT_STEP_HW_WATCHPOINTS
180 #define CANNOT_STEP_HW_WATCHPOINTS 1
183 /* Tables of how to react to signals; the user sets them. */
185 static unsigned char *signal_stop
;
186 static unsigned char *signal_print
;
187 static unsigned char *signal_program
;
189 #define SET_SIGS(nsigs,sigs,flags) \
191 int signum = (nsigs); \
192 while (signum-- > 0) \
193 if ((sigs)[signum]) \
194 (flags)[signum] = 1; \
197 #define UNSET_SIGS(nsigs,sigs,flags) \
199 int signum = (nsigs); \
200 while (signum-- > 0) \
201 if ((sigs)[signum]) \
202 (flags)[signum] = 0; \
205 /* Value to pass to target_resume() to cause all threads to resume */
207 #define RESUME_ALL (pid_to_ptid (-1))
209 /* Command list pointer for the "stop" placeholder. */
211 static struct cmd_list_element
*stop_command
;
213 /* Function inferior was in as of last step command. */
215 static struct symbol
*step_start_function
;
217 /* Nonzero if we want to give control to the user when we're notified
218 of shared library events by the dynamic linker. */
219 static int stop_on_solib_events
;
221 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
222 struct cmd_list_element
*c
, const char *value
)
224 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
228 /* Nonzero means expecting a trace trap
229 and should stop the inferior and return silently when it happens. */
233 /* Nonzero means expecting a trap and caller will handle it themselves.
234 It is used after attach, due to attaching to a process;
235 when running in the shell before the child program has been exec'd;
236 and when running some kinds of remote stuff (FIXME?). */
238 enum stop_kind stop_soon
;
240 /* Save register contents here when about to pop a stack dummy frame,
241 if-and-only-if proceed_to_finish is set.
242 Thus this contains the return value from the called function (assuming
243 values are returned in a register). */
245 struct regcache
*stop_registers
;
247 /* Nonzero after stop if current stack frame should be printed. */
249 static int stop_print_frame
;
251 /* This is a cached copy of the pid/waitstatus of the last event
252 returned by target_wait()/deprecated_target_wait_hook(). This
253 information is returned by get_last_target_status(). */
254 static ptid_t target_last_wait_ptid
;
255 static struct target_waitstatus target_last_waitstatus
;
257 static void context_switch (ptid_t ptid
);
259 void init_thread_stepping_state (struct thread_info
*tss
);
261 void init_infwait_state (void);
263 /* This is used to remember when a fork, vfork or exec event
264 was caught by a catchpoint, and thus the event is to be
265 followed at the next resume of the inferior, and not
269 enum target_waitkind kind
;
276 char *execd_pathname
;
280 static const char follow_fork_mode_child
[] = "child";
281 static const char follow_fork_mode_parent
[] = "parent";
283 static const char *follow_fork_mode_kind_names
[] = {
284 follow_fork_mode_child
,
285 follow_fork_mode_parent
,
289 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
291 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
292 struct cmd_list_element
*c
, const char *value
)
294 fprintf_filtered (file
, _("\
295 Debugger response to a program call of fork or vfork is \"%s\".\n"),
303 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
305 return target_follow_fork (follow_child
);
309 follow_inferior_reset_breakpoints (void)
311 struct thread_info
*tp
= inferior_thread ();
313 /* Was there a step_resume breakpoint? (There was if the user
314 did a "next" at the fork() call.) If so, explicitly reset its
317 step_resumes are a form of bp that are made to be per-thread.
318 Since we created the step_resume bp when the parent process
319 was being debugged, and now are switching to the child process,
320 from the breakpoint package's viewpoint, that's a switch of
321 "threads". We must update the bp's notion of which thread
322 it is for, or it'll be ignored when it triggers. */
324 if (tp
->step_resume_breakpoint
)
325 breakpoint_re_set_thread (tp
->step_resume_breakpoint
);
327 /* Reinsert all breakpoints in the child. The user may have set
328 breakpoints after catching the fork, in which case those
329 were never set in the child, but only in the parent. This makes
330 sure the inserted breakpoints match the breakpoint list. */
332 breakpoint_re_set ();
333 insert_breakpoints ();
336 /* EXECD_PATHNAME is assumed to be non-NULL. */
339 follow_exec (ptid_t pid
, char *execd_pathname
)
341 ptid_t saved_pid
= pid
;
342 struct target_ops
*tgt
;
343 struct thread_info
*th
= inferior_thread ();
345 /* This is an exec event that we actually wish to pay attention to.
346 Refresh our symbol table to the newly exec'd program, remove any
349 If there are breakpoints, they aren't really inserted now,
350 since the exec() transformed our inferior into a fresh set
353 We want to preserve symbolic breakpoints on the list, since
354 we have hopes that they can be reset after the new a.out's
355 symbol table is read.
357 However, any "raw" breakpoints must be removed from the list
358 (e.g., the solib bp's), since their address is probably invalid
361 And, we DON'T want to call delete_breakpoints() here, since
362 that may write the bp's "shadow contents" (the instruction
363 value that was overwritten witha TRAP instruction). Since
364 we now have a new a.out, those shadow contents aren't valid. */
365 update_breakpoints_after_exec ();
367 /* If there was one, it's gone now. We cannot truly step-to-next
368 statement through an exec(). */
369 th
->step_resume_breakpoint
= NULL
;
370 th
->step_range_start
= 0;
371 th
->step_range_end
= 0;
373 /* What is this a.out's name? */
374 printf_unfiltered (_("Executing new program: %s\n"), execd_pathname
);
376 /* We've followed the inferior through an exec. Therefore, the
377 inferior has essentially been killed & reborn. */
379 gdb_flush (gdb_stdout
);
380 generic_mourn_inferior ();
381 /* Because mourn_inferior resets inferior_ptid. */
382 inferior_ptid
= saved_pid
;
384 if (gdb_sysroot
&& *gdb_sysroot
)
386 char *name
= alloca (strlen (gdb_sysroot
)
387 + strlen (execd_pathname
)
389 strcpy (name
, gdb_sysroot
);
390 strcat (name
, execd_pathname
);
391 execd_pathname
= name
;
394 /* That a.out is now the one to use. */
395 exec_file_attach (execd_pathname
, 0);
397 /* Reset the shared library package. This ensures that we get a
398 shlib event when the child reaches "_start", at which point the
399 dld will have had a chance to initialize the child. */
400 /* Also, loading a symbol file below may trigger symbol lookups, and
401 we don't want those to be satisfied by the libraries of the
402 previous incarnation of this process. */
403 no_shared_libraries (NULL
, 0);
405 /* Load the main file's symbols. */
406 symbol_file_add_main (execd_pathname
, 0);
408 #ifdef SOLIB_CREATE_INFERIOR_HOOK
409 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
411 solib_create_inferior_hook ();
414 /* Reinsert all breakpoints. (Those which were symbolic have
415 been reset to the proper address in the new a.out, thanks
416 to symbol_file_command...) */
417 insert_breakpoints ();
419 /* The next resume of this inferior should bring it to the shlib
420 startup breakpoints. (If the user had also set bp's on
421 "main" from the old (parent) process, then they'll auto-
422 matically get reset there in the new process.) */
425 /* Non-zero if we just simulating a single-step. This is needed
426 because we cannot remove the breakpoints in the inferior process
427 until after the `wait' in `wait_for_inferior'. */
428 static int singlestep_breakpoints_inserted_p
= 0;
430 /* The thread we inserted single-step breakpoints for. */
431 static ptid_t singlestep_ptid
;
433 /* PC when we started this single-step. */
434 static CORE_ADDR singlestep_pc
;
436 /* If another thread hit the singlestep breakpoint, we save the original
437 thread here so that we can resume single-stepping it later. */
438 static ptid_t saved_singlestep_ptid
;
439 static int stepping_past_singlestep_breakpoint
;
441 /* If not equal to null_ptid, this means that after stepping over breakpoint
442 is finished, we need to switch to deferred_step_ptid, and step it.
444 The use case is when one thread has hit a breakpoint, and then the user
445 has switched to another thread and issued 'step'. We need to step over
446 breakpoint in the thread which hit the breakpoint, but then continue
447 stepping the thread user has selected. */
448 static ptid_t deferred_step_ptid
;
450 /* Displaced stepping. */
452 /* In non-stop debugging mode, we must take special care to manage
453 breakpoints properly; in particular, the traditional strategy for
454 stepping a thread past a breakpoint it has hit is unsuitable.
455 'Displaced stepping' is a tactic for stepping one thread past a
456 breakpoint it has hit while ensuring that other threads running
457 concurrently will hit the breakpoint as they should.
459 The traditional way to step a thread T off a breakpoint in a
460 multi-threaded program in all-stop mode is as follows:
462 a0) Initially, all threads are stopped, and breakpoints are not
464 a1) We single-step T, leaving breakpoints uninserted.
465 a2) We insert breakpoints, and resume all threads.
467 In non-stop debugging, however, this strategy is unsuitable: we
468 don't want to have to stop all threads in the system in order to
469 continue or step T past a breakpoint. Instead, we use displaced
472 n0) Initially, T is stopped, other threads are running, and
473 breakpoints are inserted.
474 n1) We copy the instruction "under" the breakpoint to a separate
475 location, outside the main code stream, making any adjustments
476 to the instruction, register, and memory state as directed by
478 n2) We single-step T over the instruction at its new location.
479 n3) We adjust the resulting register and memory state as directed
480 by T's architecture. This includes resetting T's PC to point
481 back into the main instruction stream.
484 This approach depends on the following gdbarch methods:
486 - gdbarch_max_insn_length and gdbarch_displaced_step_location
487 indicate where to copy the instruction, and how much space must
488 be reserved there. We use these in step n1.
490 - gdbarch_displaced_step_copy_insn copies a instruction to a new
491 address, and makes any necessary adjustments to the instruction,
492 register contents, and memory. We use this in step n1.
494 - gdbarch_displaced_step_fixup adjusts registers and memory after
495 we have successfuly single-stepped the instruction, to yield the
496 same effect the instruction would have had if we had executed it
497 at its original address. We use this in step n3.
499 - gdbarch_displaced_step_free_closure provides cleanup.
501 The gdbarch_displaced_step_copy_insn and
502 gdbarch_displaced_step_fixup functions must be written so that
503 copying an instruction with gdbarch_displaced_step_copy_insn,
504 single-stepping across the copied instruction, and then applying
505 gdbarch_displaced_insn_fixup should have the same effects on the
506 thread's memory and registers as stepping the instruction in place
507 would have. Exactly which responsibilities fall to the copy and
508 which fall to the fixup is up to the author of those functions.
510 See the comments in gdbarch.sh for details.
512 Note that displaced stepping and software single-step cannot
513 currently be used in combination, although with some care I think
514 they could be made to. Software single-step works by placing
515 breakpoints on all possible subsequent instructions; if the
516 displaced instruction is a PC-relative jump, those breakpoints
517 could fall in very strange places --- on pages that aren't
518 executable, or at addresses that are not proper instruction
519 boundaries. (We do generally let other threads run while we wait
520 to hit the software single-step breakpoint, and they might
521 encounter such a corrupted instruction.) One way to work around
522 this would be to have gdbarch_displaced_step_copy_insn fully
523 simulate the effect of PC-relative instructions (and return NULL)
524 on architectures that use software single-stepping.
526 In non-stop mode, we can have independent and simultaneous step
527 requests, so more than one thread may need to simultaneously step
528 over a breakpoint. The current implementation assumes there is
529 only one scratch space per process. In this case, we have to
530 serialize access to the scratch space. If thread A wants to step
531 over a breakpoint, but we are currently waiting for some other
532 thread to complete a displaced step, we leave thread A stopped and
533 place it in the displaced_step_request_queue. Whenever a displaced
534 step finishes, we pick the next thread in the queue and start a new
535 displaced step operation on it. See displaced_step_prepare and
536 displaced_step_fixup for details. */
538 /* If this is not null_ptid, this is the thread carrying out a
539 displaced single-step. This thread's state will require fixing up
540 once it has completed its step. */
541 static ptid_t displaced_step_ptid
;
543 struct displaced_step_request
546 struct displaced_step_request
*next
;
549 /* A queue of pending displaced stepping requests. */
550 struct displaced_step_request
*displaced_step_request_queue
;
552 /* The architecture the thread had when we stepped it. */
553 static struct gdbarch
*displaced_step_gdbarch
;
555 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
556 for post-step cleanup. */
557 static struct displaced_step_closure
*displaced_step_closure
;
559 /* The address of the original instruction, and the copy we made. */
560 static CORE_ADDR displaced_step_original
, displaced_step_copy
;
562 /* Saved contents of copy area. */
563 static gdb_byte
*displaced_step_saved_copy
;
565 /* When this is non-zero, we are allowed to use displaced stepping, if
566 the architecture supports it. When this is zero, we use
567 traditional the hold-and-step approach. */
568 int can_use_displaced_stepping
= 1;
570 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
571 struct cmd_list_element
*c
,
574 fprintf_filtered (file
, _("\
575 Debugger's willingness to use displaced stepping to step over "
576 "breakpoints is %s.\n"), value
);
579 /* Return non-zero if displaced stepping is enabled, and can be used
582 use_displaced_stepping (struct gdbarch
*gdbarch
)
584 return (can_use_displaced_stepping
585 && gdbarch_displaced_step_copy_insn_p (gdbarch
));
588 /* Clean out any stray displaced stepping state. */
590 displaced_step_clear (void)
592 /* Indicate that there is no cleanup pending. */
593 displaced_step_ptid
= null_ptid
;
595 if (displaced_step_closure
)
597 gdbarch_displaced_step_free_closure (displaced_step_gdbarch
,
598 displaced_step_closure
);
599 displaced_step_closure
= NULL
;
604 cleanup_displaced_step_closure (void *ptr
)
606 struct displaced_step_closure
*closure
= ptr
;
608 gdbarch_displaced_step_free_closure (current_gdbarch
, closure
);
611 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
613 displaced_step_dump_bytes (struct ui_file
*file
,
619 for (i
= 0; i
< len
; i
++)
620 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
621 fputs_unfiltered ("\n", file
);
624 /* Prepare to single-step, using displaced stepping.
626 Note that we cannot use displaced stepping when we have a signal to
627 deliver. If we have a signal to deliver and an instruction to step
628 over, then after the step, there will be no indication from the
629 target whether the thread entered a signal handler or ignored the
630 signal and stepped over the instruction successfully --- both cases
631 result in a simple SIGTRAP. In the first case we mustn't do a
632 fixup, and in the second case we must --- but we can't tell which.
633 Comments in the code for 'random signals' in handle_inferior_event
634 explain how we handle this case instead.
636 Returns 1 if preparing was successful -- this thread is going to be
637 stepped now; or 0 if displaced stepping this thread got queued. */
639 displaced_step_prepare (ptid_t ptid
)
641 struct cleanup
*old_cleanups
;
642 struct regcache
*regcache
= get_thread_regcache (ptid
);
643 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
644 CORE_ADDR original
, copy
;
646 struct displaced_step_closure
*closure
;
648 /* We should never reach this function if the architecture does not
649 support displaced stepping. */
650 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
652 /* For the first cut, we're displaced stepping one thread at a
655 if (!ptid_equal (displaced_step_ptid
, null_ptid
))
657 /* Already waiting for a displaced step to finish. Defer this
658 request and place in queue. */
659 struct displaced_step_request
*req
, *new_req
;
662 fprintf_unfiltered (gdb_stdlog
,
663 "displaced: defering step of %s\n",
664 target_pid_to_str (ptid
));
666 new_req
= xmalloc (sizeof (*new_req
));
667 new_req
->ptid
= ptid
;
668 new_req
->next
= NULL
;
670 if (displaced_step_request_queue
)
672 for (req
= displaced_step_request_queue
;
679 displaced_step_request_queue
= new_req
;
686 fprintf_unfiltered (gdb_stdlog
,
687 "displaced: stepping %s now\n",
688 target_pid_to_str (ptid
));
691 displaced_step_clear ();
693 original
= regcache_read_pc (regcache
);
695 copy
= gdbarch_displaced_step_location (gdbarch
);
696 len
= gdbarch_max_insn_length (gdbarch
);
698 /* Save the original contents of the copy area. */
699 displaced_step_saved_copy
= xmalloc (len
);
700 old_cleanups
= make_cleanup (free_current_contents
,
701 &displaced_step_saved_copy
);
702 read_memory (copy
, displaced_step_saved_copy
, len
);
705 fprintf_unfiltered (gdb_stdlog
, "displaced: saved 0x%s: ",
707 displaced_step_dump_bytes (gdb_stdlog
, displaced_step_saved_copy
, len
);
710 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
711 original
, copy
, regcache
);
713 /* We don't support the fully-simulated case at present. */
714 gdb_assert (closure
);
716 make_cleanup (cleanup_displaced_step_closure
, closure
);
718 /* Resume execution at the copy. */
719 regcache_write_pc (regcache
, copy
);
721 discard_cleanups (old_cleanups
);
724 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to 0x%s\n",
727 /* Save the information we need to fix things up if the step
729 displaced_step_ptid
= ptid
;
730 displaced_step_gdbarch
= gdbarch
;
731 displaced_step_closure
= closure
;
732 displaced_step_original
= original
;
733 displaced_step_copy
= copy
;
738 displaced_step_clear_cleanup (void *ignore
)
740 displaced_step_clear ();
744 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
, const gdb_byte
*myaddr
, int len
)
746 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
747 inferior_ptid
= ptid
;
748 write_memory (memaddr
, myaddr
, len
);
749 do_cleanups (ptid_cleanup
);
753 displaced_step_fixup (ptid_t event_ptid
, enum target_signal signal
)
755 struct cleanup
*old_cleanups
;
757 /* Was this event for the pid we displaced? */
758 if (ptid_equal (displaced_step_ptid
, null_ptid
)
759 || ! ptid_equal (displaced_step_ptid
, event_ptid
))
762 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, 0);
764 /* Restore the contents of the copy area. */
766 ULONGEST len
= gdbarch_max_insn_length (displaced_step_gdbarch
);
767 write_memory_ptid (displaced_step_ptid
, displaced_step_copy
,
768 displaced_step_saved_copy
, len
);
770 fprintf_unfiltered (gdb_stdlog
, "displaced: restored 0x%s\n",
771 paddr_nz (displaced_step_copy
));
774 /* Did the instruction complete successfully? */
775 if (signal
== TARGET_SIGNAL_TRAP
)
777 /* Fix up the resulting state. */
778 gdbarch_displaced_step_fixup (displaced_step_gdbarch
,
779 displaced_step_closure
,
780 displaced_step_original
,
782 get_thread_regcache (displaced_step_ptid
));
786 /* Since the instruction didn't complete, all we can do is
788 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
789 CORE_ADDR pc
= regcache_read_pc (regcache
);
790 pc
= displaced_step_original
+ (pc
- displaced_step_copy
);
791 regcache_write_pc (regcache
, pc
);
794 do_cleanups (old_cleanups
);
796 /* Are there any pending displaced stepping requests? If so, run
798 if (displaced_step_request_queue
)
800 struct displaced_step_request
*head
;
803 head
= displaced_step_request_queue
;
805 displaced_step_request_queue
= head
->next
;
809 fprintf_unfiltered (gdb_stdlog
,
810 "displaced: stepping queued %s now\n",
811 target_pid_to_str (ptid
));
814 displaced_step_ptid
= null_ptid
;
815 displaced_step_prepare (ptid
);
816 target_resume (ptid
, 1, TARGET_SIGNAL_0
);
820 /* Update global variables holding ptids to hold NEW_PTID if they were
823 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
825 struct displaced_step_request
*it
;
827 if (ptid_equal (inferior_ptid
, old_ptid
))
828 inferior_ptid
= new_ptid
;
830 if (ptid_equal (singlestep_ptid
, old_ptid
))
831 singlestep_ptid
= new_ptid
;
833 if (ptid_equal (displaced_step_ptid
, old_ptid
))
834 displaced_step_ptid
= new_ptid
;
836 if (ptid_equal (deferred_step_ptid
, old_ptid
))
837 deferred_step_ptid
= new_ptid
;
839 for (it
= displaced_step_request_queue
; it
; it
= it
->next
)
840 if (ptid_equal (it
->ptid
, old_ptid
))
847 /* Things to clean up if we QUIT out of resume (). */
849 resume_cleanups (void *ignore
)
854 static const char schedlock_off
[] = "off";
855 static const char schedlock_on
[] = "on";
856 static const char schedlock_step
[] = "step";
857 static const char *scheduler_enums
[] = {
863 static const char *scheduler_mode
= schedlock_off
;
865 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
866 struct cmd_list_element
*c
, const char *value
)
868 fprintf_filtered (file
, _("\
869 Mode for locking scheduler during execution is \"%s\".\n"),
874 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
876 if (!target_can_lock_scheduler
)
878 scheduler_mode
= schedlock_off
;
879 error (_("Target '%s' cannot support this command."), target_shortname
);
884 /* Resume the inferior, but allow a QUIT. This is useful if the user
885 wants to interrupt some lengthy single-stepping operation
886 (for child processes, the SIGINT goes to the inferior, and so
887 we get a SIGINT random_signal, but for remote debugging and perhaps
888 other targets, that's not true).
890 STEP nonzero if we should step (zero to continue instead).
891 SIG is the signal to give the inferior (zero for none). */
893 resume (int step
, enum target_signal sig
)
895 int should_resume
= 1;
896 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
897 struct regcache
*regcache
= get_current_regcache ();
898 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
899 struct thread_info
*tp
= inferior_thread ();
900 CORE_ADDR pc
= regcache_read_pc (regcache
);
904 fprintf_unfiltered (gdb_stdlog
,
905 "infrun: resume (step=%d, signal=%d), "
906 "trap_expected=%d\n",
907 step
, sig
, tp
->trap_expected
);
909 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
910 over an instruction that causes a page fault without triggering
911 a hardware watchpoint. The kernel properly notices that it shouldn't
912 stop, because the hardware watchpoint is not triggered, but it forgets
913 the step request and continues the program normally.
914 Work around the problem by removing hardware watchpoints if a step is
915 requested, GDB will check for a hardware watchpoint trigger after the
917 if (CANNOT_STEP_HW_WATCHPOINTS
&& step
)
918 remove_hw_watchpoints ();
921 /* Normally, by the time we reach `resume', the breakpoints are either
922 removed or inserted, as appropriate. The exception is if we're sitting
923 at a permanent breakpoint; we need to step over it, but permanent
924 breakpoints can't be removed. So we have to test for it here. */
925 if (breakpoint_here_p (pc
) == permanent_breakpoint_here
)
927 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
928 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
931 The program is stopped at a permanent breakpoint, but GDB does not know\n\
932 how to step past a permanent breakpoint on this architecture. Try using\n\
933 a command like `return' or `jump' to continue execution."));
936 /* If enabled, step over breakpoints by executing a copy of the
937 instruction at a different address.
939 We can't use displaced stepping when we have a signal to deliver;
940 the comments for displaced_step_prepare explain why. The
941 comments in the handle_inferior event for dealing with 'random
942 signals' explain what we do instead. */
943 if (use_displaced_stepping (gdbarch
)
945 && sig
== TARGET_SIGNAL_0
)
947 if (!displaced_step_prepare (inferior_ptid
))
949 /* Got placed in displaced stepping queue. Will be resumed
950 later when all the currently queued displaced stepping
951 requests finish. The thread is not executing at this point,
952 and the call to set_executing will be made later. But we
953 need to call set_running here, since from frontend point of view,
954 the thread is running. */
955 set_running (inferior_ptid
, 1);
956 discard_cleanups (old_cleanups
);
961 if (step
&& gdbarch_software_single_step_p (gdbarch
))
963 /* Do it the hard way, w/temp breakpoints */
964 if (gdbarch_software_single_step (gdbarch
, get_current_frame ()))
966 /* ...and don't ask hardware to do it. */
968 /* and do not pull these breakpoints until after a `wait' in
969 `wait_for_inferior' */
970 singlestep_breakpoints_inserted_p
= 1;
971 singlestep_ptid
= inferior_ptid
;
976 /* If there were any forks/vforks/execs that were caught and are
977 now to be followed, then do so. */
978 switch (pending_follow
.kind
)
980 case TARGET_WAITKIND_FORKED
:
981 case TARGET_WAITKIND_VFORKED
:
982 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
987 case TARGET_WAITKIND_EXECD
:
988 /* follow_exec is called as soon as the exec event is seen. */
989 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
996 /* Install inferior's terminal modes. */
997 target_terminal_inferior ();
1003 resume_ptid
= RESUME_ALL
; /* Default */
1005 /* If STEP is set, it's a request to use hardware stepping
1006 facilities. But in that case, we should never
1007 use singlestep breakpoint. */
1008 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1010 if (singlestep_breakpoints_inserted_p
1011 && stepping_past_singlestep_breakpoint
)
1013 /* The situation here is as follows. In thread T1 we wanted to
1014 single-step. Lacking hardware single-stepping we've
1015 set breakpoint at the PC of the next instruction -- call it
1016 P. After resuming, we've hit that breakpoint in thread T2.
1017 Now we've removed original breakpoint, inserted breakpoint
1018 at P+1, and try to step to advance T2 past breakpoint.
1019 We need to step only T2, as if T1 is allowed to freely run,
1020 it can run past P, and if other threads are allowed to run,
1021 they can hit breakpoint at P+1, and nested hits of single-step
1022 breakpoints is not something we'd want -- that's complicated
1023 to support, and has no value. */
1024 resume_ptid
= inferior_ptid
;
1027 if ((step
|| singlestep_breakpoints_inserted_p
)
1028 && tp
->trap_expected
)
1030 /* We're allowing a thread to run past a breakpoint it has
1031 hit, by single-stepping the thread with the breakpoint
1032 removed. In which case, we need to single-step only this
1033 thread, and keep others stopped, as they can miss this
1034 breakpoint if allowed to run.
1036 The current code actually removes all breakpoints when
1037 doing this, not just the one being stepped over, so if we
1038 let other threads run, we can actually miss any
1039 breakpoint, not just the one at PC. */
1040 resume_ptid
= inferior_ptid
;
1045 /* With non-stop mode on, threads are always handled
1047 resume_ptid
= inferior_ptid
;
1049 else if ((scheduler_mode
== schedlock_on
)
1050 || (scheduler_mode
== schedlock_step
1051 && (step
|| singlestep_breakpoints_inserted_p
)))
1053 /* User-settable 'scheduler' mode requires solo thread resume. */
1054 resume_ptid
= inferior_ptid
;
1057 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1059 /* Most targets can step a breakpoint instruction, thus
1060 executing it normally. But if this one cannot, just
1061 continue and we will hit it anyway. */
1062 if (step
&& breakpoint_inserted_here_p (pc
))
1067 && use_displaced_stepping (gdbarch
)
1068 && tp
->trap_expected
)
1070 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1071 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1074 fprintf_unfiltered (gdb_stdlog
, "displaced: run 0x%s: ",
1075 paddr_nz (actual_pc
));
1076 read_memory (actual_pc
, buf
, sizeof (buf
));
1077 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1080 target_resume (resume_ptid
, step
, sig
);
1082 /* Avoid confusing the next resume, if the next stop/resume
1083 happens to apply to another thread. */
1084 tp
->stop_signal
= TARGET_SIGNAL_0
;
1087 discard_cleanups (old_cleanups
);
1092 /* Clear out all variables saying what to do when inferior is continued.
1093 First do this, then set the ones you want, then call `proceed'. */
1096 clear_proceed_status (void)
1098 if (!ptid_equal (inferior_ptid
, null_ptid
))
1100 struct thread_info
*tp
= inferior_thread ();
1102 tp
->trap_expected
= 0;
1103 tp
->step_range_start
= 0;
1104 tp
->step_range_end
= 0;
1105 tp
->step_frame_id
= null_frame_id
;
1106 tp
->step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1110 tp
->proceed_to_finish
= 0;
1112 /* Discard any remaining commands or status from previous
1114 bpstat_clear (&tp
->stop_bpstat
);
1117 stop_after_trap
= 0;
1118 stop_soon
= NO_STOP_QUIETLY
;
1119 breakpoint_proceeded
= 1; /* We're about to proceed... */
1123 regcache_xfree (stop_registers
);
1124 stop_registers
= NULL
;
1128 /* This should be suitable for any targets that support threads. */
1131 prepare_to_proceed (int step
)
1134 struct target_waitstatus wait_status
;
1136 /* Get the last target status returned by target_wait(). */
1137 get_last_target_status (&wait_ptid
, &wait_status
);
1139 /* Make sure we were stopped at a breakpoint. */
1140 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
1141 || wait_status
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1146 /* Switched over from WAIT_PID. */
1147 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
1148 && !ptid_equal (inferior_ptid
, wait_ptid
))
1150 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
1152 if (breakpoint_here_p (regcache_read_pc (regcache
)))
1154 /* If stepping, remember current thread to switch back to. */
1156 deferred_step_ptid
= inferior_ptid
;
1158 /* Switch back to WAIT_PID thread. */
1159 switch_to_thread (wait_ptid
);
1161 /* We return 1 to indicate that there is a breakpoint here,
1162 so we need to step over it before continuing to avoid
1163 hitting it straight away. */
1171 /* Basic routine for continuing the program in various fashions.
1173 ADDR is the address to resume at, or -1 for resume where stopped.
1174 SIGGNAL is the signal to give it, or 0 for none,
1175 or -1 for act according to how it stopped.
1176 STEP is nonzero if should trap after one instruction.
1177 -1 means return after that and print nothing.
1178 You should probably set various step_... variables
1179 before calling here, if you are stepping.
1181 You should call clear_proceed_status before calling proceed. */
1184 proceed (CORE_ADDR addr
, enum target_signal siggnal
, int step
)
1186 struct regcache
*regcache
= get_current_regcache ();
1187 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1188 struct thread_info
*tp
;
1189 CORE_ADDR pc
= regcache_read_pc (regcache
);
1191 enum target_signal stop_signal
;
1194 step_start_function
= find_pc_function (pc
);
1196 stop_after_trap
= 1;
1198 if (addr
== (CORE_ADDR
) -1)
1200 if (pc
== stop_pc
&& breakpoint_here_p (pc
))
1201 /* There is a breakpoint at the address we will resume at,
1202 step one instruction before inserting breakpoints so that
1203 we do not stop right away (and report a second hit at this
1206 else if (gdbarch_single_step_through_delay_p (gdbarch
)
1207 && gdbarch_single_step_through_delay (gdbarch
,
1208 get_current_frame ()))
1209 /* We stepped onto an instruction that needs to be stepped
1210 again before re-inserting the breakpoint, do so. */
1215 regcache_write_pc (regcache
, addr
);
1219 fprintf_unfiltered (gdb_stdlog
,
1220 "infrun: proceed (addr=0x%s, signal=%d, step=%d)\n",
1221 paddr_nz (addr
), siggnal
, step
);
1224 /* In non-stop, each thread is handled individually. The context
1225 must already be set to the right thread here. */
1229 /* In a multi-threaded task we may select another thread and
1230 then continue or step.
1232 But if the old thread was stopped at a breakpoint, it will
1233 immediately cause another breakpoint stop without any
1234 execution (i.e. it will report a breakpoint hit incorrectly).
1235 So we must step over it first.
1237 prepare_to_proceed checks the current thread against the
1238 thread that reported the most recent event. If a step-over
1239 is required it returns TRUE and sets the current thread to
1241 if (prepare_to_proceed (step
))
1245 /* prepare_to_proceed may change the current thread. */
1246 tp
= inferior_thread ();
1250 tp
->trap_expected
= 1;
1251 /* If displaced stepping is enabled, we can step over the
1252 breakpoint without hitting it, so leave all breakpoints
1253 inserted. Otherwise we need to disable all breakpoints, step
1254 one instruction, and then re-add them when that step is
1256 if (!use_displaced_stepping (gdbarch
))
1257 remove_breakpoints ();
1260 /* We can insert breakpoints if we're not trying to step over one,
1261 or if we are stepping over one but we're using displaced stepping
1263 if (! tp
->trap_expected
|| use_displaced_stepping (gdbarch
))
1264 insert_breakpoints ();
1268 /* Pass the last stop signal to the thread we're resuming,
1269 irrespective of whether the current thread is the thread that
1270 got the last event or not. This was historically GDB's
1271 behaviour before keeping a stop_signal per thread. */
1273 struct thread_info
*last_thread
;
1275 struct target_waitstatus last_status
;
1277 get_last_target_status (&last_ptid
, &last_status
);
1278 if (!ptid_equal (inferior_ptid
, last_ptid
)
1279 && !ptid_equal (last_ptid
, null_ptid
)
1280 && !ptid_equal (last_ptid
, minus_one_ptid
))
1282 last_thread
= find_thread_pid (last_ptid
);
1285 tp
->stop_signal
= last_thread
->stop_signal
;
1286 last_thread
->stop_signal
= TARGET_SIGNAL_0
;
1291 if (siggnal
!= TARGET_SIGNAL_DEFAULT
)
1292 tp
->stop_signal
= siggnal
;
1293 /* If this signal should not be seen by program,
1294 give it zero. Used for debugging signals. */
1295 else if (!signal_program
[tp
->stop_signal
])
1296 tp
->stop_signal
= TARGET_SIGNAL_0
;
1298 annotate_starting ();
1300 /* Make sure that output from GDB appears before output from the
1302 gdb_flush (gdb_stdout
);
1304 /* Refresh prev_pc value just prior to resuming. This used to be
1305 done in stop_stepping, however, setting prev_pc there did not handle
1306 scenarios such as inferior function calls or returning from
1307 a function via the return command. In those cases, the prev_pc
1308 value was not set properly for subsequent commands. The prev_pc value
1309 is used to initialize the starting line number in the ecs. With an
1310 invalid value, the gdb next command ends up stopping at the position
1311 represented by the next line table entry past our start position.
1312 On platforms that generate one line table entry per line, this
1313 is not a problem. However, on the ia64, the compiler generates
1314 extraneous line table entries that do not increase the line number.
1315 When we issue the gdb next command on the ia64 after an inferior call
1316 or a return command, we often end up a few instructions forward, still
1317 within the original line we started.
1319 An attempt was made to have init_execution_control_state () refresh
1320 the prev_pc value before calculating the line number. This approach
1321 did not work because on platforms that use ptrace, the pc register
1322 cannot be read unless the inferior is stopped. At that point, we
1323 are not guaranteed the inferior is stopped and so the regcache_read_pc ()
1324 call can fail. Setting the prev_pc value here ensures the value is
1325 updated correctly when the inferior is stopped. */
1326 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
1328 /* Fill in with reasonable starting values. */
1329 init_thread_stepping_state (tp
);
1331 /* Reset to normal state. */
1332 init_infwait_state ();
1334 /* Resume inferior. */
1335 resume (oneproc
|| step
|| bpstat_should_step (), tp
->stop_signal
);
1337 /* Wait for it to stop (if not standalone)
1338 and in any case decode why it stopped, and act accordingly. */
1339 /* Do this only if we are not using the event loop, or if the target
1340 does not support asynchronous execution. */
1341 if (!target_can_async_p ())
1343 wait_for_inferior (0);
1349 /* Start remote-debugging of a machine over a serial link. */
1352 start_remote (int from_tty
)
1354 init_wait_for_inferior ();
1355 stop_soon
= STOP_QUIETLY_REMOTE
;
1357 /* Always go on waiting for the target, regardless of the mode. */
1358 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1359 indicate to wait_for_inferior that a target should timeout if
1360 nothing is returned (instead of just blocking). Because of this,
1361 targets expecting an immediate response need to, internally, set
1362 things up so that the target_wait() is forced to eventually
1364 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1365 differentiate to its caller what the state of the target is after
1366 the initial open has been performed. Here we're assuming that
1367 the target has stopped. It should be possible to eventually have
1368 target_open() return to the caller an indication that the target
1369 is currently running and GDB state should be set to the same as
1370 for an async run. */
1371 wait_for_inferior (0);
1373 /* Now that the inferior has stopped, do any bookkeeping like
1374 loading shared libraries. We want to do this before normal_stop,
1375 so that the displayed frame is up to date. */
1376 post_create_inferior (¤t_target
, from_tty
);
1381 /* Initialize static vars when a new inferior begins. */
1384 init_wait_for_inferior (void)
1386 /* These are meaningless until the first time through wait_for_inferior. */
1388 breakpoint_init_inferior (inf_starting
);
1390 /* The first resume is not following a fork/vfork/exec. */
1391 pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
; /* I.e., none. */
1393 clear_proceed_status ();
1395 stepping_past_singlestep_breakpoint
= 0;
1396 deferred_step_ptid
= null_ptid
;
1398 target_last_wait_ptid
= minus_one_ptid
;
1400 previous_inferior_ptid
= null_ptid
;
1401 init_infwait_state ();
1403 displaced_step_clear ();
1407 /* This enum encodes possible reasons for doing a target_wait, so that
1408 wfi can call target_wait in one place. (Ultimately the call will be
1409 moved out of the infinite loop entirely.) */
1413 infwait_normal_state
,
1414 infwait_thread_hop_state
,
1415 infwait_step_watch_state
,
1416 infwait_nonstep_watch_state
1419 /* Why did the inferior stop? Used to print the appropriate messages
1420 to the interface from within handle_inferior_event(). */
1421 enum inferior_stop_reason
1423 /* Step, next, nexti, stepi finished. */
1425 /* Inferior terminated by signal. */
1427 /* Inferior exited. */
1429 /* Inferior received signal, and user asked to be notified. */
1433 /* The PTID we'll do a target_wait on.*/
1436 /* Current inferior wait state. */
1437 enum infwait_states infwait_state
;
1439 /* Data to be passed around while handling an event. This data is
1440 discarded between events. */
1441 struct execution_control_state
1444 /* The thread that got the event, if this was a thread event; NULL
1446 struct thread_info
*event_thread
;
1448 struct target_waitstatus ws
;
1450 CORE_ADDR stop_func_start
;
1451 CORE_ADDR stop_func_end
;
1452 char *stop_func_name
;
1453 int new_thread_event
;
1457 void init_execution_control_state (struct execution_control_state
*ecs
);
1459 void handle_inferior_event (struct execution_control_state
*ecs
);
1461 static void step_into_function (struct execution_control_state
*ecs
);
1462 static void insert_step_resume_breakpoint_at_frame (struct frame_info
*step_frame
);
1463 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
1464 static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
1465 struct frame_id sr_id
);
1466 static void insert_longjmp_resume_breakpoint (CORE_ADDR
);
1468 static void stop_stepping (struct execution_control_state
*ecs
);
1469 static void prepare_to_wait (struct execution_control_state
*ecs
);
1470 static void keep_going (struct execution_control_state
*ecs
);
1471 static void print_stop_reason (enum inferior_stop_reason stop_reason
,
1474 /* Callback for iterate_over_threads. */
1477 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
1479 if (is_exited (info
->ptid
))
1482 delete_step_resume_breakpoint (info
);
1486 /* In all-stop, delete the step resume breakpoint of any thread that
1487 had one. In non-stop, delete the step resume breakpoint of the
1488 thread that just stopped. */
1491 delete_step_thread_step_resume_breakpoint (void)
1493 if (!target_has_execution
1494 || ptid_equal (inferior_ptid
, null_ptid
))
1495 /* If the inferior has exited, we have already deleted the step
1496 resume breakpoints out of GDB's lists. */
1501 /* If in non-stop mode, only delete the step-resume or
1502 longjmp-resume breakpoint of the thread that just stopped
1504 struct thread_info
*tp
= inferior_thread ();
1505 delete_step_resume_breakpoint (tp
);
1508 /* In all-stop mode, delete all step-resume and longjmp-resume
1509 breakpoints of any thread that had them. */
1510 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
1513 /* A cleanup wrapper. */
1516 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
1518 delete_step_thread_step_resume_breakpoint ();
1521 /* Wait for control to return from inferior to debugger.
1523 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
1524 as if they were SIGTRAP signals. This can be useful during
1525 the startup sequence on some targets such as HP/UX, where
1526 we receive an EXEC event instead of the expected SIGTRAP.
1528 If inferior gets a signal, we may decide to start it up again
1529 instead of returning. That is why there is a loop in this function.
1530 When this function actually returns it means the inferior
1531 should be left stopped and GDB should read more commands. */
1534 wait_for_inferior (int treat_exec_as_sigtrap
)
1536 struct cleanup
*old_cleanups
;
1537 struct execution_control_state ecss
;
1538 struct execution_control_state
*ecs
;
1542 (gdb_stdlog
, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
1543 treat_exec_as_sigtrap
);
1546 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
1549 memset (ecs
, 0, sizeof (*ecs
));
1551 overlay_cache_invalid
= 1;
1553 /* We'll update this if & when we switch to a new thread. */
1554 previous_inferior_ptid
= inferior_ptid
;
1556 /* We have to invalidate the registers BEFORE calling target_wait
1557 because they can be loaded from the target while in target_wait.
1558 This makes remote debugging a bit more efficient for those
1559 targets that provide critical registers as part of their normal
1560 status mechanism. */
1562 registers_changed ();
1566 if (deprecated_target_wait_hook
)
1567 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
);
1569 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
);
1571 if (treat_exec_as_sigtrap
&& ecs
->ws
.kind
== TARGET_WAITKIND_EXECD
)
1573 xfree (ecs
->ws
.value
.execd_pathname
);
1574 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
1575 ecs
->ws
.value
.sig
= TARGET_SIGNAL_TRAP
;
1578 /* Now figure out what to do with the result of the result. */
1579 handle_inferior_event (ecs
);
1581 if (!ecs
->wait_some_more
)
1585 do_cleanups (old_cleanups
);
1588 /* Asynchronous version of wait_for_inferior. It is called by the
1589 event loop whenever a change of state is detected on the file
1590 descriptor corresponding to the target. It can be called more than
1591 once to complete a single execution command. In such cases we need
1592 to keep the state in a global variable ECSS. If it is the last time
1593 that this function is called for a single execution command, then
1594 report to the user that the inferior has stopped, and do the
1595 necessary cleanups. */
1598 fetch_inferior_event (void *client_data
)
1600 struct execution_control_state ecss
;
1601 struct execution_control_state
*ecs
= &ecss
;
1602 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
1603 int was_sync
= sync_execution
;
1605 memset (ecs
, 0, sizeof (*ecs
));
1607 overlay_cache_invalid
= 1;
1609 /* We can only rely on wait_for_more being correct before handling
1610 the event in all-stop, but previous_inferior_ptid isn't used in
1612 if (!ecs
->wait_some_more
)
1613 /* We'll update this if & when we switch to a new thread. */
1614 previous_inferior_ptid
= inferior_ptid
;
1617 /* In non-stop mode, the user/frontend should not notice a thread
1618 switch due to internal events. Make sure we reverse to the
1619 user selected thread and frame after handling the event and
1620 running any breakpoint commands. */
1621 make_cleanup_restore_current_thread ();
1623 /* We have to invalidate the registers BEFORE calling target_wait
1624 because they can be loaded from the target while in target_wait.
1625 This makes remote debugging a bit more efficient for those
1626 targets that provide critical registers as part of their normal
1627 status mechanism. */
1629 registers_changed ();
1631 if (deprecated_target_wait_hook
)
1633 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
);
1635 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
);
1638 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
1639 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1640 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
1641 /* In non-stop mode, each thread is handled individually. Switch
1642 early, so the global state is set correctly for this
1644 context_switch (ecs
->ptid
);
1646 /* Now figure out what to do with the result of the result. */
1647 handle_inferior_event (ecs
);
1649 if (!ecs
->wait_some_more
)
1651 delete_step_thread_step_resume_breakpoint ();
1653 if (stop_soon
== NO_STOP_QUIETLY
)
1656 if (target_has_execution
1657 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1658 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
1659 && ecs
->event_thread
->step_multi
1660 && ecs
->event_thread
->stop_step
)
1661 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
1663 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
1666 /* Revert thread and frame. */
1667 do_cleanups (old_chain
);
1669 /* If the inferior was in sync execution mode, and now isn't,
1670 restore the prompt. */
1671 if (was_sync
&& !sync_execution
)
1672 display_gdb_prompt (0);
1675 /* Prepare an execution control state for looping through a
1676 wait_for_inferior-type loop. */
1679 init_execution_control_state (struct execution_control_state
*ecs
)
1681 ecs
->random_signal
= 0;
1684 /* Clear context switchable stepping state. */
1687 init_thread_stepping_state (struct thread_info
*tss
)
1689 struct symtab_and_line sal
;
1691 tss
->stepping_over_breakpoint
= 0;
1692 tss
->step_after_step_resume_breakpoint
= 0;
1693 tss
->stepping_through_solib_after_catch
= 0;
1694 tss
->stepping_through_solib_catchpoints
= NULL
;
1696 sal
= find_pc_line (tss
->prev_pc
, 0);
1697 tss
->current_line
= sal
.line
;
1698 tss
->current_symtab
= sal
.symtab
;
1701 /* Return the cached copy of the last pid/waitstatus returned by
1702 target_wait()/deprecated_target_wait_hook(). The data is actually
1703 cached by handle_inferior_event(), which gets called immediately
1704 after target_wait()/deprecated_target_wait_hook(). */
1707 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
1709 *ptidp
= target_last_wait_ptid
;
1710 *status
= target_last_waitstatus
;
1714 nullify_last_target_wait_ptid (void)
1716 target_last_wait_ptid
= minus_one_ptid
;
1719 /* Switch thread contexts. */
1722 context_switch (ptid_t ptid
)
1726 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
1727 target_pid_to_str (inferior_ptid
));
1728 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
1729 target_pid_to_str (ptid
));
1732 switch_to_thread (ptid
);
1736 adjust_pc_after_break (struct execution_control_state
*ecs
)
1738 struct regcache
*regcache
;
1739 struct gdbarch
*gdbarch
;
1740 CORE_ADDR breakpoint_pc
;
1742 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
1743 we aren't, just return.
1745 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
1746 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
1747 implemented by software breakpoints should be handled through the normal
1750 NOTE drow/2004-01-31: On some targets, breakpoints may generate
1751 different signals (SIGILL or SIGEMT for instance), but it is less
1752 clear where the PC is pointing afterwards. It may not match
1753 gdbarch_decr_pc_after_break. I don't know any specific target that
1754 generates these signals at breakpoints (the code has been in GDB since at
1755 least 1992) so I can not guess how to handle them here.
1757 In earlier versions of GDB, a target with
1758 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
1759 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
1760 target with both of these set in GDB history, and it seems unlikely to be
1761 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
1763 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
1766 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
1769 /* If this target does not decrement the PC after breakpoints, then
1770 we have nothing to do. */
1771 regcache
= get_thread_regcache (ecs
->ptid
);
1772 gdbarch
= get_regcache_arch (regcache
);
1773 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
1776 /* Find the location where (if we've hit a breakpoint) the
1777 breakpoint would be. */
1778 breakpoint_pc
= regcache_read_pc (regcache
)
1779 - gdbarch_decr_pc_after_break (gdbarch
);
1781 /* Check whether there actually is a software breakpoint inserted
1782 at that location. */
1783 if (software_breakpoint_inserted_here_p (breakpoint_pc
))
1785 /* When using hardware single-step, a SIGTRAP is reported for both
1786 a completed single-step and a software breakpoint. Need to
1787 differentiate between the two, as the latter needs adjusting
1788 but the former does not.
1790 The SIGTRAP can be due to a completed hardware single-step only if
1791 - we didn't insert software single-step breakpoints
1792 - the thread to be examined is still the current thread
1793 - this thread is currently being stepped
1795 If any of these events did not occur, we must have stopped due
1796 to hitting a software breakpoint, and have to back up to the
1799 As a special case, we could have hardware single-stepped a
1800 software breakpoint. In this case (prev_pc == breakpoint_pc),
1801 we also need to back up to the breakpoint address. */
1803 if (singlestep_breakpoints_inserted_p
1804 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
1805 || !currently_stepping (ecs
->event_thread
)
1806 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
1807 regcache_write_pc (regcache
, breakpoint_pc
);
1812 init_infwait_state (void)
1814 waiton_ptid
= pid_to_ptid (-1);
1815 infwait_state
= infwait_normal_state
;
1819 error_is_running (void)
1822 Cannot execute this command while the selected thread is running."));
1826 ensure_not_running (void)
1828 if (is_running (inferior_ptid
))
1829 error_is_running ();
1832 /* Given an execution control state that has been freshly filled in
1833 by an event from the inferior, figure out what it means and take
1834 appropriate action. */
1837 handle_inferior_event (struct execution_control_state
*ecs
)
1839 int sw_single_step_trap_p
= 0;
1840 int stopped_by_watchpoint
;
1841 int stepped_after_stopped_by_watchpoint
= 0;
1842 struct symtab_and_line stop_pc_sal
;
1844 breakpoint_retire_moribund ();
1846 /* Cache the last pid/waitstatus. */
1847 target_last_wait_ptid
= ecs
->ptid
;
1848 target_last_waitstatus
= ecs
->ws
;
1850 /* Always clear state belonging to the previous time we stopped. */
1851 stop_stack_dummy
= 0;
1853 /* If it's a new process, add it to the thread database */
1855 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
1856 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
1857 && !in_thread_list (ecs
->ptid
));
1859 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
1860 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
1861 add_thread (ecs
->ptid
);
1863 ecs
->event_thread
= find_thread_pid (ecs
->ptid
);
1865 /* Dependent on valid ECS->EVENT_THREAD. */
1866 adjust_pc_after_break (ecs
);
1868 /* Dependent on the current PC value modified by adjust_pc_after_break. */
1869 reinit_frame_cache ();
1871 if (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
)
1873 /* Mark the non-executing threads accordingly. */
1875 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
1876 || ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
1877 set_executing (pid_to_ptid (-1), 0);
1879 set_executing (ecs
->ptid
, 0);
1882 switch (infwait_state
)
1884 case infwait_thread_hop_state
:
1886 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
1887 /* Cancel the waiton_ptid. */
1888 waiton_ptid
= pid_to_ptid (-1);
1891 case infwait_normal_state
:
1893 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
1896 case infwait_step_watch_state
:
1898 fprintf_unfiltered (gdb_stdlog
,
1899 "infrun: infwait_step_watch_state\n");
1901 stepped_after_stopped_by_watchpoint
= 1;
1904 case infwait_nonstep_watch_state
:
1906 fprintf_unfiltered (gdb_stdlog
,
1907 "infrun: infwait_nonstep_watch_state\n");
1908 insert_breakpoints ();
1910 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1911 handle things like signals arriving and other things happening
1912 in combination correctly? */
1913 stepped_after_stopped_by_watchpoint
= 1;
1917 internal_error (__FILE__
, __LINE__
, _("bad switch"));
1919 infwait_state
= infwait_normal_state
;
1921 switch (ecs
->ws
.kind
)
1923 case TARGET_WAITKIND_LOADED
:
1925 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
1926 /* Ignore gracefully during startup of the inferior, as it might
1927 be the shell which has just loaded some objects, otherwise
1928 add the symbols for the newly loaded objects. Also ignore at
1929 the beginning of an attach or remote session; we will query
1930 the full list of libraries once the connection is
1932 if (stop_soon
== NO_STOP_QUIETLY
)
1934 /* Check for any newly added shared libraries if we're
1935 supposed to be adding them automatically. Switch
1936 terminal for any messages produced by
1937 breakpoint_re_set. */
1938 target_terminal_ours_for_output ();
1939 /* NOTE: cagney/2003-11-25: Make certain that the target
1940 stack's section table is kept up-to-date. Architectures,
1941 (e.g., PPC64), use the section table to perform
1942 operations such as address => section name and hence
1943 require the table to contain all sections (including
1944 those found in shared libraries). */
1945 /* NOTE: cagney/2003-11-25: Pass current_target and not
1946 exec_ops to SOLIB_ADD. This is because current GDB is
1947 only tooled to propagate section_table changes out from
1948 the "current_target" (see target_resize_to_sections), and
1949 not up from the exec stratum. This, of course, isn't
1950 right. "infrun.c" should only interact with the
1951 exec/process stratum, instead relying on the target stack
1952 to propagate relevant changes (stop, section table
1953 changed, ...) up to other layers. */
1955 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
1957 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
1959 target_terminal_inferior ();
1961 /* If requested, stop when the dynamic linker notifies
1962 gdb of events. This allows the user to get control
1963 and place breakpoints in initializer routines for
1964 dynamically loaded objects (among other things). */
1965 if (stop_on_solib_events
)
1967 stop_stepping (ecs
);
1971 /* NOTE drow/2007-05-11: This might be a good place to check
1972 for "catch load". */
1975 /* If we are skipping through a shell, or through shared library
1976 loading that we aren't interested in, resume the program. If
1977 we're running the program normally, also resume. But stop if
1978 we're attaching or setting up a remote connection. */
1979 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
1981 /* Loading of shared libraries might have changed breakpoint
1982 addresses. Make sure new breakpoints are inserted. */
1983 if (stop_soon
== NO_STOP_QUIETLY
1984 && !breakpoints_always_inserted_mode ())
1985 insert_breakpoints ();
1986 resume (0, TARGET_SIGNAL_0
);
1987 prepare_to_wait (ecs
);
1993 case TARGET_WAITKIND_SPURIOUS
:
1995 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
1996 resume (0, TARGET_SIGNAL_0
);
1997 prepare_to_wait (ecs
);
2000 case TARGET_WAITKIND_EXITED
:
2002 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
2003 target_terminal_ours (); /* Must do this before mourn anyway */
2004 print_stop_reason (EXITED
, ecs
->ws
.value
.integer
);
2006 /* Record the exit code in the convenience variable $_exitcode, so
2007 that the user can inspect this again later. */
2008 set_internalvar (lookup_internalvar ("_exitcode"),
2009 value_from_longest (builtin_type_int32
,
2010 (LONGEST
) ecs
->ws
.value
.integer
));
2011 gdb_flush (gdb_stdout
);
2012 target_mourn_inferior ();
2013 singlestep_breakpoints_inserted_p
= 0;
2014 stop_print_frame
= 0;
2015 stop_stepping (ecs
);
2018 case TARGET_WAITKIND_SIGNALLED
:
2020 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2021 stop_print_frame
= 0;
2022 target_terminal_ours (); /* Must do this before mourn anyway */
2024 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2025 reach here unless the inferior is dead. However, for years
2026 target_kill() was called here, which hints that fatal signals aren't
2027 really fatal on some systems. If that's true, then some changes
2029 target_mourn_inferior ();
2031 print_stop_reason (SIGNAL_EXITED
, ecs
->ws
.value
.sig
);
2032 singlestep_breakpoints_inserted_p
= 0;
2033 stop_stepping (ecs
);
2036 /* The following are the only cases in which we keep going;
2037 the above cases end in a continue or goto. */
2038 case TARGET_WAITKIND_FORKED
:
2039 case TARGET_WAITKIND_VFORKED
:
2041 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
2042 pending_follow
.kind
= ecs
->ws
.kind
;
2044 pending_follow
.fork_event
.parent_pid
= ecs
->ptid
;
2045 pending_follow
.fork_event
.child_pid
= ecs
->ws
.value
.related_pid
;
2047 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2049 context_switch (ecs
->ptid
);
2050 reinit_frame_cache ();
2053 stop_pc
= read_pc ();
2055 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2057 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2059 /* If no catchpoint triggered for this, then keep going. */
2060 if (ecs
->random_signal
)
2062 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2066 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2067 goto process_event_stop_test
;
2069 case TARGET_WAITKIND_EXECD
:
2071 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
2072 pending_follow
.execd_pathname
=
2073 savestring (ecs
->ws
.value
.execd_pathname
,
2074 strlen (ecs
->ws
.value
.execd_pathname
));
2076 /* This causes the eventpoints and symbol table to be reset. Must
2077 do this now, before trying to determine whether to stop. */
2078 follow_exec (inferior_ptid
, pending_follow
.execd_pathname
);
2079 xfree (pending_follow
.execd_pathname
);
2081 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2084 /* The breakpoints module may need to touch the inferior's
2085 memory. Switch to the (stopped) event ptid
2087 ptid_t saved_inferior_ptid
= inferior_ptid
;
2088 inferior_ptid
= ecs
->ptid
;
2090 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2092 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2093 inferior_ptid
= saved_inferior_ptid
;
2096 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2098 context_switch (ecs
->ptid
);
2099 reinit_frame_cache ();
2102 /* If no catchpoint triggered for this, then keep going. */
2103 if (ecs
->random_signal
)
2105 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2109 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2110 goto process_event_stop_test
;
2112 /* Be careful not to try to gather much state about a thread
2113 that's in a syscall. It's frequently a losing proposition. */
2114 case TARGET_WAITKIND_SYSCALL_ENTRY
:
2116 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2117 resume (0, TARGET_SIGNAL_0
);
2118 prepare_to_wait (ecs
);
2121 /* Before examining the threads further, step this thread to
2122 get it entirely out of the syscall. (We get notice of the
2123 event when the thread is just on the verge of exiting a
2124 syscall. Stepping one instruction seems to get it back
2126 case TARGET_WAITKIND_SYSCALL_RETURN
:
2128 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2129 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
);
2130 prepare_to_wait (ecs
);
2133 case TARGET_WAITKIND_STOPPED
:
2135 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
2136 ecs
->event_thread
->stop_signal
= ecs
->ws
.value
.sig
;
2139 /* We had an event in the inferior, but we are not interested
2140 in handling it at this level. The lower layers have already
2141 done what needs to be done, if anything.
2143 One of the possible circumstances for this is when the
2144 inferior produces output for the console. The inferior has
2145 not stopped, and we are ignoring the event. Another possible
2146 circumstance is any event which the lower level knows will be
2147 reported multiple times without an intervening resume. */
2148 case TARGET_WAITKIND_IGNORE
:
2150 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
2151 prepare_to_wait (ecs
);
2155 if (ecs
->new_thread_event
)
2158 /* Non-stop assumes that the target handles adding new threads
2159 to the thread list. */
2160 internal_error (__FILE__
, __LINE__
, "\
2161 targets should add new threads to the thread list themselves in non-stop mode.");
2163 /* We may want to consider not doing a resume here in order to
2164 give the user a chance to play with the new thread. It might
2165 be good to make that a user-settable option. */
2167 /* At this point, all threads are stopped (happens automatically
2168 in either the OS or the native code). Therefore we need to
2169 continue all threads in order to make progress. */
2171 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
2172 prepare_to_wait (ecs
);
2176 /* Do we need to clean up the state of a thread that has completed a
2177 displaced single-step? (Doing so usually affects the PC, so do
2178 it here, before we set stop_pc.) */
2179 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
2180 displaced_step_fixup (ecs
->ptid
, ecs
->event_thread
->stop_signal
);
2182 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
2186 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = 0x%s\n",
2187 paddr_nz (stop_pc
));
2188 if (STOPPED_BY_WATCHPOINT (&ecs
->ws
))
2191 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
2193 if (target_stopped_data_address (¤t_target
, &addr
))
2194 fprintf_unfiltered (gdb_stdlog
,
2195 "infrun: stopped data address = 0x%s\n",
2198 fprintf_unfiltered (gdb_stdlog
,
2199 "infrun: (no data address available)\n");
2203 if (stepping_past_singlestep_breakpoint
)
2205 gdb_assert (singlestep_breakpoints_inserted_p
);
2206 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
2207 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
2209 stepping_past_singlestep_breakpoint
= 0;
2211 /* We've either finished single-stepping past the single-step
2212 breakpoint, or stopped for some other reason. It would be nice if
2213 we could tell, but we can't reliably. */
2214 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2217 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping_past_singlestep_breakpoint\n");
2218 /* Pull the single step breakpoints out of the target. */
2219 remove_single_step_breakpoints ();
2220 singlestep_breakpoints_inserted_p
= 0;
2222 ecs
->random_signal
= 0;
2224 context_switch (saved_singlestep_ptid
);
2225 if (deprecated_context_hook
)
2226 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2228 resume (1, TARGET_SIGNAL_0
);
2229 prepare_to_wait (ecs
);
2234 stepping_past_singlestep_breakpoint
= 0;
2236 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
2238 /* In non-stop mode, there's never a deferred_step_ptid set. */
2239 gdb_assert (!non_stop
);
2241 /* If we stopped for some other reason than single-stepping, ignore
2242 the fact that we were supposed to switch back. */
2243 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2245 struct thread_info
*tp
;
2248 fprintf_unfiltered (gdb_stdlog
,
2249 "infrun: handling deferred step\n");
2251 /* Pull the single step breakpoints out of the target. */
2252 if (singlestep_breakpoints_inserted_p
)
2254 remove_single_step_breakpoints ();
2255 singlestep_breakpoints_inserted_p
= 0;
2258 /* Note: We do not call context_switch at this point, as the
2259 context is already set up for stepping the original thread. */
2260 switch_to_thread (deferred_step_ptid
);
2261 deferred_step_ptid
= null_ptid
;
2262 /* Suppress spurious "Switching to ..." message. */
2263 previous_inferior_ptid
= inferior_ptid
;
2265 resume (1, TARGET_SIGNAL_0
);
2266 prepare_to_wait (ecs
);
2270 deferred_step_ptid
= null_ptid
;
2273 /* See if a thread hit a thread-specific breakpoint that was meant for
2274 another thread. If so, then step that thread past the breakpoint,
2277 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2279 int thread_hop_needed
= 0;
2281 /* Check if a regular breakpoint has been hit before checking
2282 for a potential single step breakpoint. Otherwise, GDB will
2283 not see this breakpoint hit when stepping onto breakpoints. */
2284 if (regular_breakpoint_inserted_here_p (stop_pc
))
2286 ecs
->random_signal
= 0;
2287 if (!breakpoint_thread_match (stop_pc
, ecs
->ptid
))
2288 thread_hop_needed
= 1;
2290 else if (singlestep_breakpoints_inserted_p
)
2292 /* We have not context switched yet, so this should be true
2293 no matter which thread hit the singlestep breakpoint. */
2294 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
2296 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
2298 target_pid_to_str (ecs
->ptid
));
2300 ecs
->random_signal
= 0;
2301 /* The call to in_thread_list is necessary because PTIDs sometimes
2302 change when we go from single-threaded to multi-threaded. If
2303 the singlestep_ptid is still in the list, assume that it is
2304 really different from ecs->ptid. */
2305 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
2306 && in_thread_list (singlestep_ptid
))
2308 /* If the PC of the thread we were trying to single-step
2309 has changed, discard this event (which we were going
2310 to ignore anyway), and pretend we saw that thread
2311 trap. This prevents us continuously moving the
2312 single-step breakpoint forward, one instruction at a
2313 time. If the PC has changed, then the thread we were
2314 trying to single-step has trapped or been signalled,
2315 but the event has not been reported to GDB yet.
2317 There might be some cases where this loses signal
2318 information, if a signal has arrived at exactly the
2319 same time that the PC changed, but this is the best
2320 we can do with the information available. Perhaps we
2321 should arrange to report all events for all threads
2322 when they stop, or to re-poll the remote looking for
2323 this particular thread (i.e. temporarily enable
2326 CORE_ADDR new_singlestep_pc
2327 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
2329 if (new_singlestep_pc
!= singlestep_pc
)
2331 enum target_signal stop_signal
;
2334 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
2335 " but expected thread advanced also\n");
2337 /* The current context still belongs to
2338 singlestep_ptid. Don't swap here, since that's
2339 the context we want to use. Just fudge our
2340 state and continue. */
2341 stop_signal
= ecs
->event_thread
->stop_signal
;
2342 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2343 ecs
->ptid
= singlestep_ptid
;
2344 ecs
->event_thread
= find_thread_pid (ecs
->ptid
);
2345 ecs
->event_thread
->stop_signal
= stop_signal
;
2346 stop_pc
= new_singlestep_pc
;
2351 fprintf_unfiltered (gdb_stdlog
,
2352 "infrun: unexpected thread\n");
2354 thread_hop_needed
= 1;
2355 stepping_past_singlestep_breakpoint
= 1;
2356 saved_singlestep_ptid
= singlestep_ptid
;
2361 if (thread_hop_needed
)
2363 int remove_status
= 0;
2366 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
2368 /* Saw a breakpoint, but it was hit by the wrong thread.
2371 if (singlestep_breakpoints_inserted_p
)
2373 /* Pull the single step breakpoints out of the target. */
2374 remove_single_step_breakpoints ();
2375 singlestep_breakpoints_inserted_p
= 0;
2378 /* If the arch can displace step, don't remove the
2380 if (!use_displaced_stepping (current_gdbarch
))
2381 remove_status
= remove_breakpoints ();
2383 /* Did we fail to remove breakpoints? If so, try
2384 to set the PC past the bp. (There's at least
2385 one situation in which we can fail to remove
2386 the bp's: On HP-UX's that use ttrace, we can't
2387 change the address space of a vforking child
2388 process until the child exits (well, okay, not
2389 then either :-) or execs. */
2390 if (remove_status
!= 0)
2391 error (_("Cannot step over breakpoint hit in wrong thread"));
2394 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
2395 context_switch (ecs
->ptid
);
2399 /* Only need to require the next event from this
2400 thread in all-stop mode. */
2401 waiton_ptid
= ecs
->ptid
;
2402 infwait_state
= infwait_thread_hop_state
;
2405 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2407 registers_changed ();
2411 else if (singlestep_breakpoints_inserted_p
)
2413 sw_single_step_trap_p
= 1;
2414 ecs
->random_signal
= 0;
2418 ecs
->random_signal
= 1;
2420 /* See if something interesting happened to the non-current thread. If
2421 so, then switch to that thread. */
2422 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
2425 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
2427 context_switch (ecs
->ptid
);
2429 if (deprecated_context_hook
)
2430 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
2433 if (singlestep_breakpoints_inserted_p
)
2435 /* Pull the single step breakpoints out of the target. */
2436 remove_single_step_breakpoints ();
2437 singlestep_breakpoints_inserted_p
= 0;
2440 if (stepped_after_stopped_by_watchpoint
)
2441 stopped_by_watchpoint
= 0;
2443 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
2445 /* If necessary, step over this watchpoint. We'll be back to display
2447 if (stopped_by_watchpoint
2448 && (HAVE_STEPPABLE_WATCHPOINT
2449 || gdbarch_have_nonsteppable_watchpoint (current_gdbarch
)))
2451 /* At this point, we are stopped at an instruction which has
2452 attempted to write to a piece of memory under control of
2453 a watchpoint. The instruction hasn't actually executed
2454 yet. If we were to evaluate the watchpoint expression
2455 now, we would get the old value, and therefore no change
2456 would seem to have occurred.
2458 In order to make watchpoints work `right', we really need
2459 to complete the memory write, and then evaluate the
2460 watchpoint expression. We do this by single-stepping the
2463 It may not be necessary to disable the watchpoint to stop over
2464 it. For example, the PA can (with some kernel cooperation)
2465 single step over a watchpoint without disabling the watchpoint.
2467 It is far more common to need to disable a watchpoint to step
2468 the inferior over it. If we have non-steppable watchpoints,
2469 we must disable the current watchpoint; it's simplest to
2470 disable all watchpoints and breakpoints. */
2472 if (!HAVE_STEPPABLE_WATCHPOINT
)
2473 remove_breakpoints ();
2474 registers_changed ();
2475 target_resume (ecs
->ptid
, 1, TARGET_SIGNAL_0
); /* Single step */
2476 waiton_ptid
= ecs
->ptid
;
2477 if (HAVE_STEPPABLE_WATCHPOINT
)
2478 infwait_state
= infwait_step_watch_state
;
2480 infwait_state
= infwait_nonstep_watch_state
;
2481 prepare_to_wait (ecs
);
2485 ecs
->stop_func_start
= 0;
2486 ecs
->stop_func_end
= 0;
2487 ecs
->stop_func_name
= 0;
2488 /* Don't care about return value; stop_func_start and stop_func_name
2489 will both be 0 if it doesn't work. */
2490 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
2491 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
2492 ecs
->stop_func_start
2493 += gdbarch_deprecated_function_start_offset (current_gdbarch
);
2494 ecs
->event_thread
->stepping_over_breakpoint
= 0;
2495 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
2496 ecs
->event_thread
->stop_step
= 0;
2497 stop_print_frame
= 1;
2498 ecs
->random_signal
= 0;
2499 stopped_by_random_signal
= 0;
2501 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
2502 && ecs
->event_thread
->trap_expected
2503 && gdbarch_single_step_through_delay_p (current_gdbarch
)
2504 && currently_stepping (ecs
->event_thread
))
2506 /* We're trying to step off a breakpoint. Turns out that we're
2507 also on an instruction that needs to be stepped multiple
2508 times before it's been fully executing. E.g., architectures
2509 with a delay slot. It needs to be stepped twice, once for
2510 the instruction and once for the delay slot. */
2511 int step_through_delay
2512 = gdbarch_single_step_through_delay (current_gdbarch
,
2513 get_current_frame ());
2514 if (debug_infrun
&& step_through_delay
)
2515 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
2516 if (ecs
->event_thread
->step_range_end
== 0 && step_through_delay
)
2518 /* The user issued a continue when stopped at a breakpoint.
2519 Set up for another trap and get out of here. */
2520 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2524 else if (step_through_delay
)
2526 /* The user issued a step when stopped at a breakpoint.
2527 Maybe we should stop, maybe we should not - the delay
2528 slot *might* correspond to a line of source. In any
2529 case, don't decide that here, just set
2530 ecs->stepping_over_breakpoint, making sure we
2531 single-step again before breakpoints are re-inserted. */
2532 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2536 /* Look at the cause of the stop, and decide what to do.
2537 The alternatives are:
2538 1) stop_stepping and return; to really stop and return to the debugger,
2539 2) keep_going and return to start up again
2540 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
2541 3) set ecs->random_signal to 1, and the decision between 1 and 2
2542 will be made according to the signal handling tables. */
2544 /* First, distinguish signals caused by the debugger from signals
2545 that have to do with the program's own actions. Note that
2546 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
2547 on the operating system version. Here we detect when a SIGILL or
2548 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
2549 something similar for SIGSEGV, since a SIGSEGV will be generated
2550 when we're trying to execute a breakpoint instruction on a
2551 non-executable stack. This happens for call dummy breakpoints
2552 for architectures like SPARC that place call dummies on the
2555 If we're doing a displaced step past a breakpoint, then the
2556 breakpoint is always inserted at the original instruction;
2557 non-standard signals can't be explained by the breakpoint. */
2558 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
2559 || (! ecs
->event_thread
->trap_expected
2560 && breakpoint_inserted_here_p (stop_pc
)
2561 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_ILL
2562 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_SEGV
2563 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_EMT
))
2564 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2565 || stop_soon
== STOP_QUIETLY_REMOTE
)
2567 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
&& stop_after_trap
)
2570 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
2571 stop_print_frame
= 0;
2572 stop_stepping (ecs
);
2576 /* This is originated from start_remote(), start_inferior() and
2577 shared libraries hook functions. */
2578 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
2581 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
2582 stop_stepping (ecs
);
2586 /* This originates from attach_command(). We need to overwrite
2587 the stop_signal here, because some kernels don't ignore a
2588 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
2589 See more comments in inferior.h. On the other hand, if we
2590 get a non-SIGSTOP, report it to the user - assume the backend
2591 will handle the SIGSTOP if it should show up later.
2593 Also consider that the attach is complete when we see a
2594 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
2595 target extended-remote report it instead of a SIGSTOP
2596 (e.g. gdbserver). We already rely on SIGTRAP being our
2597 signal, so this is no exception. */
2598 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
2599 && (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_STOP
2600 || ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
))
2602 stop_stepping (ecs
);
2603 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2607 /* See if there is a breakpoint at the current PC. */
2608 ecs
->event_thread
->stop_bpstat
= bpstat_stop_status (stop_pc
, ecs
->ptid
);
2610 /* Following in case break condition called a
2612 stop_print_frame
= 1;
2614 /* NOTE: cagney/2003-03-29: These two checks for a random signal
2615 at one stage in the past included checks for an inferior
2616 function call's call dummy's return breakpoint. The original
2617 comment, that went with the test, read:
2619 ``End of a stack dummy. Some systems (e.g. Sony news) give
2620 another signal besides SIGTRAP, so check here as well as
2623 If someone ever tries to get get call dummys on a
2624 non-executable stack to work (where the target would stop
2625 with something like a SIGSEGV), then those tests might need
2626 to be re-instated. Given, however, that the tests were only
2627 enabled when momentary breakpoints were not being used, I
2628 suspect that it won't be the case.
2630 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
2631 be necessary for call dummies on a non-executable stack on
2634 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
)
2636 = !(bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
)
2637 || ecs
->event_thread
->trap_expected
2638 || (ecs
->event_thread
->step_range_end
2639 && ecs
->event_thread
->step_resume_breakpoint
== NULL
));
2642 ecs
->random_signal
= !bpstat_explains_signal (ecs
->event_thread
->stop_bpstat
);
2643 if (!ecs
->random_signal
)
2644 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_TRAP
;
2648 /* When we reach this point, we've pretty much decided
2649 that the reason for stopping must've been a random
2650 (unexpected) signal. */
2653 ecs
->random_signal
= 1;
2655 process_event_stop_test
:
2656 /* For the program's own signals, act according to
2657 the signal handling tables. */
2659 if (ecs
->random_signal
)
2661 /* Signal not for debugging purposes. */
2665 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
2666 ecs
->event_thread
->stop_signal
);
2668 stopped_by_random_signal
= 1;
2670 if (signal_print
[ecs
->event_thread
->stop_signal
])
2673 target_terminal_ours_for_output ();
2674 print_stop_reason (SIGNAL_RECEIVED
, ecs
->event_thread
->stop_signal
);
2676 if (signal_stop_state (ecs
->event_thread
->stop_signal
))
2678 stop_stepping (ecs
);
2681 /* If not going to stop, give terminal back
2682 if we took it away. */
2684 target_terminal_inferior ();
2686 /* Clear the signal if it should not be passed. */
2687 if (signal_program
[ecs
->event_thread
->stop_signal
] == 0)
2688 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
2690 if (ecs
->event_thread
->prev_pc
== read_pc ()
2691 && ecs
->event_thread
->trap_expected
2692 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
2694 /* We were just starting a new sequence, attempting to
2695 single-step off of a breakpoint and expecting a SIGTRAP.
2696 Instead this signal arrives. This signal will take us out
2697 of the stepping range so GDB needs to remember to, when
2698 the signal handler returns, resume stepping off that
2700 /* To simplify things, "continue" is forced to use the same
2701 code paths as single-step - set a breakpoint at the
2702 signal return address and then, once hit, step off that
2705 fprintf_unfiltered (gdb_stdlog
,
2706 "infrun: signal arrived while stepping over "
2709 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2710 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
2715 if (ecs
->event_thread
->step_range_end
!= 0
2716 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_0
2717 && (ecs
->event_thread
->step_range_start
<= stop_pc
2718 && stop_pc
< ecs
->event_thread
->step_range_end
)
2719 && frame_id_eq (get_frame_id (get_current_frame ()),
2720 ecs
->event_thread
->step_frame_id
)
2721 && ecs
->event_thread
->step_resume_breakpoint
== NULL
)
2723 /* The inferior is about to take a signal that will take it
2724 out of the single step range. Set a breakpoint at the
2725 current PC (which is presumably where the signal handler
2726 will eventually return) and then allow the inferior to
2729 Note that this is only needed for a signal delivered
2730 while in the single-step range. Nested signals aren't a
2731 problem as they eventually all return. */
2733 fprintf_unfiltered (gdb_stdlog
,
2734 "infrun: signal may take us out of "
2735 "single-step range\n");
2737 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2742 /* Note: step_resume_breakpoint may be non-NULL. This occures
2743 when either there's a nested signal, or when there's a
2744 pending signal enabled just as the signal handler returns
2745 (leaving the inferior at the step-resume-breakpoint without
2746 actually executing it). Either way continue until the
2747 breakpoint is really hit. */
2752 /* Handle cases caused by hitting a breakpoint. */
2754 CORE_ADDR jmp_buf_pc
;
2755 struct bpstat_what what
;
2757 what
= bpstat_what (ecs
->event_thread
->stop_bpstat
);
2759 if (what
.call_dummy
)
2761 stop_stack_dummy
= 1;
2764 switch (what
.main_action
)
2766 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
2767 /* If we hit the breakpoint at longjmp while stepping, we
2768 install a momentary breakpoint at the target of the
2772 fprintf_unfiltered (gdb_stdlog
,
2773 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
2775 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2777 if (!gdbarch_get_longjmp_target_p (current_gdbarch
)
2778 || !gdbarch_get_longjmp_target (current_gdbarch
,
2779 get_current_frame (), &jmp_buf_pc
))
2782 fprintf_unfiltered (gdb_stdlog
, "\
2783 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
2788 /* We're going to replace the current step-resume breakpoint
2789 with a longjmp-resume breakpoint. */
2790 delete_step_resume_breakpoint (ecs
->event_thread
);
2792 /* Insert a breakpoint at resume address. */
2793 insert_longjmp_resume_breakpoint (jmp_buf_pc
);
2798 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
2800 fprintf_unfiltered (gdb_stdlog
,
2801 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
2803 gdb_assert (ecs
->event_thread
->step_resume_breakpoint
!= NULL
);
2804 delete_step_resume_breakpoint (ecs
->event_thread
);
2806 ecs
->event_thread
->stop_step
= 1;
2807 print_stop_reason (END_STEPPING_RANGE
, 0);
2808 stop_stepping (ecs
);
2811 case BPSTAT_WHAT_SINGLE
:
2813 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
2814 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2815 /* Still need to check other stuff, at least the case
2816 where we are stepping and step out of the right range. */
2819 case BPSTAT_WHAT_STOP_NOISY
:
2821 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
2822 stop_print_frame
= 1;
2824 /* We are about to nuke the step_resume_breakpointt via the
2825 cleanup chain, so no need to worry about it here. */
2827 stop_stepping (ecs
);
2830 case BPSTAT_WHAT_STOP_SILENT
:
2832 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
2833 stop_print_frame
= 0;
2835 /* We are about to nuke the step_resume_breakpoin via the
2836 cleanup chain, so no need to worry about it here. */
2838 stop_stepping (ecs
);
2841 case BPSTAT_WHAT_STEP_RESUME
:
2843 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
2845 delete_step_resume_breakpoint (ecs
->event_thread
);
2846 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
2848 /* Back when the step-resume breakpoint was inserted, we
2849 were trying to single-step off a breakpoint. Go back
2851 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
2852 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2858 case BPSTAT_WHAT_CHECK_SHLIBS
:
2859 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
:
2862 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
2864 /* Check for any newly added shared libraries if we're
2865 supposed to be adding them automatically. Switch
2866 terminal for any messages produced by
2867 breakpoint_re_set. */
2868 target_terminal_ours_for_output ();
2869 /* NOTE: cagney/2003-11-25: Make certain that the target
2870 stack's section table is kept up-to-date. Architectures,
2871 (e.g., PPC64), use the section table to perform
2872 operations such as address => section name and hence
2873 require the table to contain all sections (including
2874 those found in shared libraries). */
2875 /* NOTE: cagney/2003-11-25: Pass current_target and not
2876 exec_ops to SOLIB_ADD. This is because current GDB is
2877 only tooled to propagate section_table changes out from
2878 the "current_target" (see target_resize_to_sections), and
2879 not up from the exec stratum. This, of course, isn't
2880 right. "infrun.c" should only interact with the
2881 exec/process stratum, instead relying on the target stack
2882 to propagate relevant changes (stop, section table
2883 changed, ...) up to other layers. */
2885 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
2887 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
2889 target_terminal_inferior ();
2891 /* If requested, stop when the dynamic linker notifies
2892 gdb of events. This allows the user to get control
2893 and place breakpoints in initializer routines for
2894 dynamically loaded objects (among other things). */
2895 if (stop_on_solib_events
|| stop_stack_dummy
)
2897 stop_stepping (ecs
);
2901 /* If we stopped due to an explicit catchpoint, then the
2902 (see above) call to SOLIB_ADD pulled in any symbols
2903 from a newly-loaded library, if appropriate.
2905 We do want the inferior to stop, but not where it is
2906 now, which is in the dynamic linker callback. Rather,
2907 we would like it stop in the user's program, just after
2908 the call that caused this catchpoint to trigger. That
2909 gives the user a more useful vantage from which to
2910 examine their program's state. */
2911 else if (what
.main_action
2912 == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
)
2914 /* ??rehrauer: If I could figure out how to get the
2915 right return PC from here, we could just set a temp
2916 breakpoint and resume. I'm not sure we can without
2917 cracking open the dld's shared libraries and sniffing
2918 their unwind tables and text/data ranges, and that's
2919 not a terribly portable notion.
2921 Until that time, we must step the inferior out of the
2922 dld callback, and also out of the dld itself (and any
2923 code or stubs in libdld.sl, such as "shl_load" and
2924 friends) until we reach non-dld code. At that point,
2925 we can stop stepping. */
2926 bpstat_get_triggered_catchpoints (ecs
->event_thread
->stop_bpstat
,
2929 stepping_through_solib_catchpoints
);
2930 ecs
->event_thread
->stepping_through_solib_after_catch
= 1;
2932 /* Be sure to lift all breakpoints, so the inferior does
2933 actually step past this point... */
2934 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2939 /* We want to step over this breakpoint, then keep going. */
2940 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2946 case BPSTAT_WHAT_LAST
:
2947 /* Not a real code, but listed here to shut up gcc -Wall. */
2949 case BPSTAT_WHAT_KEEP_CHECKING
:
2954 /* We come here if we hit a breakpoint but should not
2955 stop for it. Possibly we also were stepping
2956 and should stop for that. So fall through and
2957 test for stepping. But, if not stepping,
2960 /* Are we stepping to get the inferior out of the dynamic linker's
2961 hook (and possibly the dld itself) after catching a shlib
2963 if (ecs
->event_thread
->stepping_through_solib_after_catch
)
2965 #if defined(SOLIB_ADD)
2966 /* Have we reached our destination? If not, keep going. */
2967 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
2970 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping in dynamic linker\n");
2971 ecs
->event_thread
->stepping_over_breakpoint
= 1;
2977 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
2978 /* Else, stop and report the catchpoint(s) whose triggering
2979 caused us to begin stepping. */
2980 ecs
->event_thread
->stepping_through_solib_after_catch
= 0;
2981 bpstat_clear (&ecs
->event_thread
->stop_bpstat
);
2982 ecs
->event_thread
->stop_bpstat
2983 = bpstat_copy (ecs
->event_thread
->stepping_through_solib_catchpoints
);
2984 bpstat_clear (&ecs
->event_thread
->stepping_through_solib_catchpoints
);
2985 stop_print_frame
= 1;
2986 stop_stepping (ecs
);
2990 if (ecs
->event_thread
->step_resume_breakpoint
)
2993 fprintf_unfiltered (gdb_stdlog
,
2994 "infrun: step-resume breakpoint is inserted\n");
2996 /* Having a step-resume breakpoint overrides anything
2997 else having to do with stepping commands until
2998 that breakpoint is reached. */
3003 if (ecs
->event_thread
->step_range_end
== 0)
3006 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
3007 /* Likewise if we aren't even stepping. */
3012 /* If stepping through a line, keep going if still within it.
3014 Note that step_range_end is the address of the first instruction
3015 beyond the step range, and NOT the address of the last instruction
3017 if (stop_pc
>= ecs
->event_thread
->step_range_start
3018 && stop_pc
< ecs
->event_thread
->step_range_end
)
3021 fprintf_unfiltered (gdb_stdlog
, "infrun: stepping inside range [0x%s-0x%s]\n",
3022 paddr_nz (ecs
->event_thread
->step_range_start
),
3023 paddr_nz (ecs
->event_thread
->step_range_end
));
3028 /* We stepped out of the stepping range. */
3030 /* If we are stepping at the source level and entered the runtime
3031 loader dynamic symbol resolution code, we keep on single stepping
3032 until we exit the run time loader code and reach the callee's
3034 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3035 && in_solib_dynsym_resolve_code (stop_pc
))
3037 CORE_ADDR pc_after_resolver
=
3038 gdbarch_skip_solib_resolver (current_gdbarch
, stop_pc
);
3041 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into dynsym resolve code\n");
3043 if (pc_after_resolver
)
3045 /* Set up a step-resume breakpoint at the address
3046 indicated by SKIP_SOLIB_RESOLVER. */
3047 struct symtab_and_line sr_sal
;
3049 sr_sal
.pc
= pc_after_resolver
;
3051 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3058 if (ecs
->event_thread
->step_range_end
!= 1
3059 && (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3060 || ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3061 && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME
)
3064 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into signal trampoline\n");
3065 /* The inferior, while doing a "step" or "next", has ended up in
3066 a signal trampoline (either by a signal being delivered or by
3067 the signal handler returning). Just single-step until the
3068 inferior leaves the trampoline (either by calling the handler
3074 /* Check for subroutine calls. The check for the current frame
3075 equalling the step ID is not necessary - the check of the
3076 previous frame's ID is sufficient - but it is a common case and
3077 cheaper than checking the previous frame's ID.
3079 NOTE: frame_id_eq will never report two invalid frame IDs as
3080 being equal, so to get into this block, both the current and
3081 previous frame must have valid frame IDs. */
3082 if (!frame_id_eq (get_frame_id (get_current_frame ()),
3083 ecs
->event_thread
->step_frame_id
)
3084 && frame_id_eq (frame_unwind_id (get_current_frame ()),
3085 ecs
->event_thread
->step_frame_id
))
3087 CORE_ADDR real_stop_pc
;
3090 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
3092 if ((ecs
->event_thread
->step_over_calls
== STEP_OVER_NONE
)
3093 || ((ecs
->event_thread
->step_range_end
== 1)
3094 && in_prologue (ecs
->event_thread
->prev_pc
,
3095 ecs
->stop_func_start
)))
3097 /* I presume that step_over_calls is only 0 when we're
3098 supposed to be stepping at the assembly language level
3099 ("stepi"). Just stop. */
3100 /* Also, maybe we just did a "nexti" inside a prolog, so we
3101 thought it was a subroutine call but it was not. Stop as
3103 ecs
->event_thread
->stop_step
= 1;
3104 print_stop_reason (END_STEPPING_RANGE
, 0);
3105 stop_stepping (ecs
);
3109 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_ALL
)
3111 /* We're doing a "next", set a breakpoint at callee's return
3112 address (the address at which the caller will
3114 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3119 /* If we are in a function call trampoline (a stub between the
3120 calling routine and the real function), locate the real
3121 function. That's what tells us (a) whether we want to step
3122 into it at all, and (b) what prologue we want to run to the
3123 end of, if we do step into it. */
3124 real_stop_pc
= skip_language_trampoline (get_current_frame (), stop_pc
);
3125 if (real_stop_pc
== 0)
3126 real_stop_pc
= gdbarch_skip_trampoline_code
3127 (current_gdbarch
, get_current_frame (), stop_pc
);
3128 if (real_stop_pc
!= 0)
3129 ecs
->stop_func_start
= real_stop_pc
;
3131 if (in_solib_dynsym_resolve_code (ecs
->stop_func_start
))
3133 struct symtab_and_line sr_sal
;
3135 sr_sal
.pc
= ecs
->stop_func_start
;
3137 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3142 /* If we have line number information for the function we are
3143 thinking of stepping into, step into it.
3145 If there are several symtabs at that PC (e.g. with include
3146 files), just want to know whether *any* of them have line
3147 numbers. find_pc_line handles this. */
3149 struct symtab_and_line tmp_sal
;
3151 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3152 if (tmp_sal
.line
!= 0)
3154 step_into_function (ecs
);
3159 /* If we have no line number and the step-stop-if-no-debug is
3160 set, we stop the step so that the user has a chance to switch
3161 in assembly mode. */
3162 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3163 && step_stop_if_no_debug
)
3165 ecs
->event_thread
->stop_step
= 1;
3166 print_stop_reason (END_STEPPING_RANGE
, 0);
3167 stop_stepping (ecs
);
3171 /* Set a breakpoint at callee's return address (the address at
3172 which the caller will resume). */
3173 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3178 /* If we're in the return path from a shared library trampoline,
3179 we want to proceed through the trampoline when stepping. */
3180 if (gdbarch_in_solib_return_trampoline (current_gdbarch
,
3181 stop_pc
, ecs
->stop_func_name
))
3183 /* Determine where this trampoline returns. */
3184 CORE_ADDR real_stop_pc
;
3185 real_stop_pc
= gdbarch_skip_trampoline_code
3186 (current_gdbarch
, get_current_frame (), stop_pc
);
3189 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into solib return tramp\n");
3191 /* Only proceed through if we know where it's going. */
3194 /* And put the step-breakpoint there and go until there. */
3195 struct symtab_and_line sr_sal
;
3197 init_sal (&sr_sal
); /* initialize to zeroes */
3198 sr_sal
.pc
= real_stop_pc
;
3199 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3201 /* Do not specify what the fp should be when we stop since
3202 on some machines the prologue is where the new fp value
3204 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3206 /* Restart without fiddling with the step ranges or
3213 stop_pc_sal
= find_pc_line (stop_pc
, 0);
3215 /* NOTE: tausq/2004-05-24: This if block used to be done before all
3216 the trampoline processing logic, however, there are some trampolines
3217 that have no names, so we should do trampoline handling first. */
3218 if (ecs
->event_thread
->step_over_calls
== STEP_OVER_UNDEBUGGABLE
3219 && ecs
->stop_func_name
== NULL
3220 && stop_pc_sal
.line
== 0)
3223 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into undebuggable function\n");
3225 /* The inferior just stepped into, or returned to, an
3226 undebuggable function (where there is no debugging information
3227 and no line number corresponding to the address where the
3228 inferior stopped). Since we want to skip this kind of code,
3229 we keep going until the inferior returns from this
3230 function - unless the user has asked us not to (via
3231 set step-mode) or we no longer know how to get back
3232 to the call site. */
3233 if (step_stop_if_no_debug
3234 || !frame_id_p (frame_unwind_id (get_current_frame ())))
3236 /* If we have no line number and the step-stop-if-no-debug
3237 is set, we stop the step so that the user has a chance to
3238 switch in assembly mode. */
3239 ecs
->event_thread
->stop_step
= 1;
3240 print_stop_reason (END_STEPPING_RANGE
, 0);
3241 stop_stepping (ecs
);
3246 /* Set a breakpoint at callee's return address (the address
3247 at which the caller will resume). */
3248 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3254 if (ecs
->event_thread
->step_range_end
== 1)
3256 /* It is stepi or nexti. We always want to stop stepping after
3259 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
3260 ecs
->event_thread
->stop_step
= 1;
3261 print_stop_reason (END_STEPPING_RANGE
, 0);
3262 stop_stepping (ecs
);
3266 if (stop_pc_sal
.line
== 0)
3268 /* We have no line number information. That means to stop
3269 stepping (does this always happen right after one instruction,
3270 when we do "s" in a function with no line numbers,
3271 or can this happen as a result of a return or longjmp?). */
3273 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
3274 ecs
->event_thread
->stop_step
= 1;
3275 print_stop_reason (END_STEPPING_RANGE
, 0);
3276 stop_stepping (ecs
);
3280 if ((stop_pc
== stop_pc_sal
.pc
)
3281 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
3282 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
3284 /* We are at the start of a different line. So stop. Note that
3285 we don't stop if we step into the middle of a different line.
3286 That is said to make things like for (;;) statements work
3289 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped to a different line\n");
3290 ecs
->event_thread
->stop_step
= 1;
3291 print_stop_reason (END_STEPPING_RANGE
, 0);
3292 stop_stepping (ecs
);
3296 /* We aren't done stepping.
3298 Optimize by setting the stepping range to the line.
3299 (We might not be in the original line, but if we entered a
3300 new line in mid-statement, we continue stepping. This makes
3301 things like for(;;) statements work better.) */
3303 ecs
->event_thread
->step_range_start
= stop_pc_sal
.pc
;
3304 ecs
->event_thread
->step_range_end
= stop_pc_sal
.end
;
3305 ecs
->event_thread
->step_frame_id
= get_frame_id (get_current_frame ());
3306 ecs
->event_thread
->current_line
= stop_pc_sal
.line
;
3307 ecs
->event_thread
->current_symtab
= stop_pc_sal
.symtab
;
3310 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
3314 /* Are we in the middle of stepping? */
3317 currently_stepping (struct thread_info
*tp
)
3319 return (((tp
->step_range_end
&& tp
->step_resume_breakpoint
== NULL
)
3320 || tp
->trap_expected
)
3321 || tp
->stepping_through_solib_after_catch
3322 || bpstat_should_step ());
3325 /* Subroutine call with source code we should not step over. Do step
3326 to the first line of code in it. */
3329 step_into_function (struct execution_control_state
*ecs
)
3332 struct symtab_and_line stop_func_sal
, sr_sal
;
3334 s
= find_pc_symtab (stop_pc
);
3335 if (s
&& s
->language
!= language_asm
)
3336 ecs
->stop_func_start
= gdbarch_skip_prologue
3337 (current_gdbarch
, ecs
->stop_func_start
);
3339 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
3340 /* Use the step_resume_break to step until the end of the prologue,
3341 even if that involves jumps (as it seems to on the vax under
3343 /* If the prologue ends in the middle of a source line, continue to
3344 the end of that source line (if it is still within the function).
3345 Otherwise, just go to end of prologue. */
3346 if (stop_func_sal
.end
3347 && stop_func_sal
.pc
!= ecs
->stop_func_start
3348 && stop_func_sal
.end
< ecs
->stop_func_end
)
3349 ecs
->stop_func_start
= stop_func_sal
.end
;
3351 /* Architectures which require breakpoint adjustment might not be able
3352 to place a breakpoint at the computed address. If so, the test
3353 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
3354 ecs->stop_func_start to an address at which a breakpoint may be
3355 legitimately placed.
3357 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
3358 made, GDB will enter an infinite loop when stepping through
3359 optimized code consisting of VLIW instructions which contain
3360 subinstructions corresponding to different source lines. On
3361 FR-V, it's not permitted to place a breakpoint on any but the
3362 first subinstruction of a VLIW instruction. When a breakpoint is
3363 set, GDB will adjust the breakpoint address to the beginning of
3364 the VLIW instruction. Thus, we need to make the corresponding
3365 adjustment here when computing the stop address. */
3367 if (gdbarch_adjust_breakpoint_address_p (current_gdbarch
))
3369 ecs
->stop_func_start
3370 = gdbarch_adjust_breakpoint_address (current_gdbarch
,
3371 ecs
->stop_func_start
);
3374 if (ecs
->stop_func_start
== stop_pc
)
3376 /* We are already there: stop now. */
3377 ecs
->event_thread
->stop_step
= 1;
3378 print_stop_reason (END_STEPPING_RANGE
, 0);
3379 stop_stepping (ecs
);
3384 /* Put the step-breakpoint there and go until there. */
3385 init_sal (&sr_sal
); /* initialize to zeroes */
3386 sr_sal
.pc
= ecs
->stop_func_start
;
3387 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
3389 /* Do not specify what the fp should be when we stop since on
3390 some machines the prologue is where the new fp value is
3392 insert_step_resume_breakpoint_at_sal (sr_sal
, null_frame_id
);
3394 /* And make sure stepping stops right away then. */
3395 ecs
->event_thread
->step_range_end
= ecs
->event_thread
->step_range_start
;
3400 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
3401 This is used to both functions and to skip over code. */
3404 insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal
,
3405 struct frame_id sr_id
)
3407 /* There should never be more than one step-resume or longjmp-resume
3408 breakpoint per thread, so we should never be setting a new
3409 step_resume_breakpoint when one is already active. */
3410 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
3413 fprintf_unfiltered (gdb_stdlog
,
3414 "infrun: inserting step-resume breakpoint at 0x%s\n",
3415 paddr_nz (sr_sal
.pc
));
3417 inferior_thread ()->step_resume_breakpoint
3418 = set_momentary_breakpoint (sr_sal
, sr_id
, bp_step_resume
);
3421 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
3422 to skip a potential signal handler.
3424 This is called with the interrupted function's frame. The signal
3425 handler, when it returns, will resume the interrupted function at
3429 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
3431 struct symtab_and_line sr_sal
;
3433 gdb_assert (return_frame
!= NULL
);
3434 init_sal (&sr_sal
); /* initialize to zeros */
3436 sr_sal
.pc
= gdbarch_addr_bits_remove
3437 (current_gdbarch
, get_frame_pc (return_frame
));
3438 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3440 insert_step_resume_breakpoint_at_sal (sr_sal
, get_frame_id (return_frame
));
3443 /* Similar to insert_step_resume_breakpoint_at_frame, except
3444 but a breakpoint at the previous frame's PC. This is used to
3445 skip a function after stepping into it (for "next" or if the called
3446 function has no debugging information).
3448 The current function has almost always been reached by single
3449 stepping a call or return instruction. NEXT_FRAME belongs to the
3450 current function, and the breakpoint will be set at the caller's
3453 This is a separate function rather than reusing
3454 insert_step_resume_breakpoint_at_frame in order to avoid
3455 get_prev_frame, which may stop prematurely (see the implementation
3456 of frame_unwind_id for an example). */
3459 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
3461 struct symtab_and_line sr_sal
;
3463 /* We shouldn't have gotten here if we don't know where the call site
3465 gdb_assert (frame_id_p (frame_unwind_id (next_frame
)));
3467 init_sal (&sr_sal
); /* initialize to zeros */
3469 sr_sal
.pc
= gdbarch_addr_bits_remove
3470 (current_gdbarch
, frame_pc_unwind (next_frame
));
3471 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
3473 insert_step_resume_breakpoint_at_sal (sr_sal
, frame_unwind_id (next_frame
));
3476 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
3477 new breakpoint at the target of a jmp_buf. The handling of
3478 longjmp-resume uses the same mechanisms used for handling
3479 "step-resume" breakpoints. */
3482 insert_longjmp_resume_breakpoint (CORE_ADDR pc
)
3484 /* There should never be more than one step-resume or longjmp-resume
3485 breakpoint per thread, so we should never be setting a new
3486 longjmp_resume_breakpoint when one is already active. */
3487 gdb_assert (inferior_thread ()->step_resume_breakpoint
== NULL
);
3490 fprintf_unfiltered (gdb_stdlog
,
3491 "infrun: inserting longjmp-resume breakpoint at 0x%s\n",
3494 inferior_thread ()->step_resume_breakpoint
=
3495 set_momentary_breakpoint_at_pc (pc
, bp_longjmp_resume
);
3499 stop_stepping (struct execution_control_state
*ecs
)
3502 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
3504 /* Let callers know we don't want to wait for the inferior anymore. */
3505 ecs
->wait_some_more
= 0;
3508 /* This function handles various cases where we need to continue
3509 waiting for the inferior. */
3510 /* (Used to be the keep_going: label in the old wait_for_inferior) */
3513 keep_going (struct execution_control_state
*ecs
)
3515 /* Save the pc before execution, to compare with pc after stop. */
3516 ecs
->event_thread
->prev_pc
= read_pc (); /* Might have been DECR_AFTER_BREAK */
3518 /* If we did not do break;, it means we should keep running the
3519 inferior and not return to debugger. */
3521 if (ecs
->event_thread
->trap_expected
3522 && ecs
->event_thread
->stop_signal
!= TARGET_SIGNAL_TRAP
)
3524 /* We took a signal (which we are supposed to pass through to
3525 the inferior, else we'd not get here) and we haven't yet
3526 gotten our trap. Simply continue. */
3527 resume (currently_stepping (ecs
->event_thread
),
3528 ecs
->event_thread
->stop_signal
);
3532 /* Either the trap was not expected, but we are continuing
3533 anyway (the user asked that this signal be passed to the
3536 The signal was SIGTRAP, e.g. it was our signal, but we
3537 decided we should resume from it.
3539 We're going to run this baby now!
3541 Note that insert_breakpoints won't try to re-insert
3542 already inserted breakpoints. Therefore, we don't
3543 care if breakpoints were already inserted, or not. */
3545 if (ecs
->event_thread
->stepping_over_breakpoint
)
3547 if (! use_displaced_stepping (current_gdbarch
))
3548 /* Since we can't do a displaced step, we have to remove
3549 the breakpoint while we step it. To keep things
3550 simple, we remove them all. */
3551 remove_breakpoints ();
3555 struct gdb_exception e
;
3556 /* Stop stepping when inserting breakpoints
3558 TRY_CATCH (e
, RETURN_MASK_ERROR
)
3560 insert_breakpoints ();
3564 stop_stepping (ecs
);
3569 ecs
->event_thread
->trap_expected
= ecs
->event_thread
->stepping_over_breakpoint
;
3571 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3572 specifies that such a signal should be delivered to the
3575 Typically, this would occure when a user is debugging a
3576 target monitor on a simulator: the target monitor sets a
3577 breakpoint; the simulator encounters this break-point and
3578 halts the simulation handing control to GDB; GDB, noteing
3579 that the break-point isn't valid, returns control back to the
3580 simulator; the simulator then delivers the hardware
3581 equivalent of a SIGNAL_TRAP to the program being debugged. */
3583 if (ecs
->event_thread
->stop_signal
== TARGET_SIGNAL_TRAP
3584 && !signal_program
[ecs
->event_thread
->stop_signal
])
3585 ecs
->event_thread
->stop_signal
= TARGET_SIGNAL_0
;
3587 resume (currently_stepping (ecs
->event_thread
),
3588 ecs
->event_thread
->stop_signal
);
3591 prepare_to_wait (ecs
);
3594 /* This function normally comes after a resume, before
3595 handle_inferior_event exits. It takes care of any last bits of
3596 housekeeping, and sets the all-important wait_some_more flag. */
3599 prepare_to_wait (struct execution_control_state
*ecs
)
3602 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
3603 if (infwait_state
== infwait_normal_state
)
3605 overlay_cache_invalid
= 1;
3607 /* We have to invalidate the registers BEFORE calling
3608 target_wait because they can be loaded from the target while
3609 in target_wait. This makes remote debugging a bit more
3610 efficient for those targets that provide critical registers
3611 as part of their normal status mechanism. */
3613 registers_changed ();
3614 waiton_ptid
= pid_to_ptid (-1);
3616 /* This is the old end of the while loop. Let everybody know we
3617 want to wait for the inferior some more and get called again
3619 ecs
->wait_some_more
= 1;
3622 /* Print why the inferior has stopped. We always print something when
3623 the inferior exits, or receives a signal. The rest of the cases are
3624 dealt with later on in normal_stop() and print_it_typical(). Ideally
3625 there should be a call to this function from handle_inferior_event()
3626 each time stop_stepping() is called.*/
3628 print_stop_reason (enum inferior_stop_reason stop_reason
, int stop_info
)
3630 switch (stop_reason
)
3632 case END_STEPPING_RANGE
:
3633 /* We are done with a step/next/si/ni command. */
3634 /* For now print nothing. */
3635 /* Print a message only if not in the middle of doing a "step n"
3636 operation for n > 1 */
3637 if (!inferior_thread ()->step_multi
3638 || !inferior_thread ()->stop_step
)
3639 if (ui_out_is_mi_like_p (uiout
))
3642 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
3645 /* The inferior was terminated by a signal. */
3646 annotate_signalled ();
3647 if (ui_out_is_mi_like_p (uiout
))
3650 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
3651 ui_out_text (uiout
, "\nProgram terminated with signal ");
3652 annotate_signal_name ();
3653 ui_out_field_string (uiout
, "signal-name",
3654 target_signal_to_name (stop_info
));
3655 annotate_signal_name_end ();
3656 ui_out_text (uiout
, ", ");
3657 annotate_signal_string ();
3658 ui_out_field_string (uiout
, "signal-meaning",
3659 target_signal_to_string (stop_info
));
3660 annotate_signal_string_end ();
3661 ui_out_text (uiout
, ".\n");
3662 ui_out_text (uiout
, "The program no longer exists.\n");
3665 /* The inferior program is finished. */
3666 annotate_exited (stop_info
);
3669 if (ui_out_is_mi_like_p (uiout
))
3670 ui_out_field_string (uiout
, "reason",
3671 async_reason_lookup (EXEC_ASYNC_EXITED
));
3672 ui_out_text (uiout
, "\nProgram exited with code ");
3673 ui_out_field_fmt (uiout
, "exit-code", "0%o",
3674 (unsigned int) stop_info
);
3675 ui_out_text (uiout
, ".\n");
3679 if (ui_out_is_mi_like_p (uiout
))
3682 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
3683 ui_out_text (uiout
, "\nProgram exited normally.\n");
3685 /* Support the --return-child-result option. */
3686 return_child_result_value
= stop_info
;
3688 case SIGNAL_RECEIVED
:
3689 /* Signal received. The signal table tells us to print about
3692 ui_out_text (uiout
, "\nProgram received signal ");
3693 annotate_signal_name ();
3694 if (ui_out_is_mi_like_p (uiout
))
3696 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
3697 ui_out_field_string (uiout
, "signal-name",
3698 target_signal_to_name (stop_info
));
3699 annotate_signal_name_end ();
3700 ui_out_text (uiout
, ", ");
3701 annotate_signal_string ();
3702 ui_out_field_string (uiout
, "signal-meaning",
3703 target_signal_to_string (stop_info
));
3704 annotate_signal_string_end ();
3705 ui_out_text (uiout
, ".\n");
3708 internal_error (__FILE__
, __LINE__
,
3709 _("print_stop_reason: unrecognized enum value"));
3715 /* Here to return control to GDB when the inferior stops for real.
3716 Print appropriate messages, remove breakpoints, give terminal our modes.
3718 STOP_PRINT_FRAME nonzero means print the executing frame
3719 (pc, function, args, file, line number and line text).
3720 BREAKPOINTS_FAILED nonzero means stop was due to error
3721 attempting to insert breakpoints. */
3726 struct target_waitstatus last
;
3729 get_last_target_status (&last_ptid
, &last
);
3731 /* In non-stop mode, we don't want GDB to switch threads behind the
3732 user's back, to avoid races where the user is typing a command to
3733 apply to thread x, but GDB switches to thread y before the user
3734 finishes entering the command. */
3736 /* As with the notification of thread events, we want to delay
3737 notifying the user that we've switched thread context until
3738 the inferior actually stops.
3740 There's no point in saying anything if the inferior has exited.
3741 Note that SIGNALLED here means "exited with a signal", not
3742 "received a signal". */
3744 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
3745 && target_has_execution
3746 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3747 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3749 target_terminal_ours_for_output ();
3750 printf_filtered (_("[Switching to %s]\n"),
3751 target_pid_to_str (inferior_ptid
));
3752 annotate_thread_changed ();
3753 previous_inferior_ptid
= inferior_ptid
;
3756 /* NOTE drow/2004-01-17: Is this still necessary? */
3757 /* Make sure that the current_frame's pc is correct. This
3758 is a correction for setting up the frame info before doing
3759 gdbarch_decr_pc_after_break */
3760 if (target_has_execution
)
3761 /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
3762 gdbarch_decr_pc_after_break, the program counter can change. Ask the
3763 frame code to check for this and sort out any resultant mess.
3764 gdbarch_decr_pc_after_break needs to just go away. */
3765 deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
3767 if (!breakpoints_always_inserted_mode () && target_has_execution
)
3769 if (remove_breakpoints ())
3771 target_terminal_ours_for_output ();
3772 printf_filtered (_("\
3773 Cannot remove breakpoints because program is no longer writable.\n\
3774 It might be running in another process.\n\
3775 Further execution is probably impossible.\n"));
3779 /* If an auto-display called a function and that got a signal,
3780 delete that auto-display to avoid an infinite recursion. */
3782 if (stopped_by_random_signal
)
3783 disable_current_display ();
3785 /* Don't print a message if in the middle of doing a "step n"
3786 operation for n > 1 */
3787 if (target_has_execution
3788 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3789 && last
.kind
!= TARGET_WAITKIND_EXITED
3790 && inferior_thread ()->step_multi
3791 && inferior_thread ()->stop_step
)
3794 target_terminal_ours ();
3796 /* Set the current source location. This will also happen if we
3797 display the frame below, but the current SAL will be incorrect
3798 during a user hook-stop function. */
3799 if (target_has_stack
&& !stop_stack_dummy
)
3800 set_current_sal_from_frame (get_current_frame (), 1);
3802 if (!target_has_stack
)
3805 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
3806 || last
.kind
== TARGET_WAITKIND_EXITED
)
3809 /* Select innermost stack frame - i.e., current frame is frame 0,
3810 and current location is based on that.
3811 Don't do this on return from a stack dummy routine,
3812 or if the program has exited. */
3814 if (!stop_stack_dummy
)
3816 select_frame (get_current_frame ());
3818 /* Print current location without a level number, if
3819 we have changed functions or hit a breakpoint.
3820 Print source line if we have one.
3821 bpstat_print() contains the logic deciding in detail
3822 what to print, based on the event(s) that just occurred. */
3824 /* If --batch-silent is enabled then there's no need to print the current
3825 source location, and to try risks causing an error message about
3826 missing source files. */
3827 if (stop_print_frame
&& !batch_silent
)
3831 int do_frame_printing
= 1;
3832 struct thread_info
*tp
= inferior_thread ();
3834 bpstat_ret
= bpstat_print (tp
->stop_bpstat
);
3838 /* If we had hit a shared library event breakpoint,
3839 bpstat_print would print out this message. If we hit
3840 an OS-level shared library event, do the same
3842 if (last
.kind
== TARGET_WAITKIND_LOADED
)
3844 printf_filtered (_("Stopped due to shared library event\n"));
3845 source_flag
= SRC_LINE
; /* something bogus */
3846 do_frame_printing
= 0;
3850 /* FIXME: cagney/2002-12-01: Given that a frame ID does
3851 (or should) carry around the function and does (or
3852 should) use that when doing a frame comparison. */
3854 && frame_id_eq (tp
->step_frame_id
,
3855 get_frame_id (get_current_frame ()))
3856 && step_start_function
== find_pc_function (stop_pc
))
3857 source_flag
= SRC_LINE
; /* finished step, just print source line */
3859 source_flag
= SRC_AND_LOC
; /* print location and source line */
3861 case PRINT_SRC_AND_LOC
:
3862 source_flag
= SRC_AND_LOC
; /* print location and source line */
3864 case PRINT_SRC_ONLY
:
3865 source_flag
= SRC_LINE
;
3868 source_flag
= SRC_LINE
; /* something bogus */
3869 do_frame_printing
= 0;
3872 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
3875 if (ui_out_is_mi_like_p (uiout
))
3878 ui_out_field_int (uiout
, "thread-id",
3879 pid_to_thread_id (inferior_ptid
));
3882 struct cleanup
*back_to
= make_cleanup_ui_out_list_begin_end
3883 (uiout
, "stopped-threads");
3884 ui_out_field_int (uiout
, NULL
,
3885 pid_to_thread_id (inferior_ptid
));
3886 do_cleanups (back_to
);
3889 ui_out_field_string (uiout
, "stopped-threads", "all");
3891 /* The behavior of this routine with respect to the source
3893 SRC_LINE: Print only source line
3894 LOCATION: Print only location
3895 SRC_AND_LOC: Print location and source line */
3896 if (do_frame_printing
)
3897 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
3899 /* Display the auto-display expressions. */
3904 /* Save the function value return registers, if we care.
3905 We might be about to restore their previous contents. */
3906 if (inferior_thread ()->proceed_to_finish
)
3908 /* This should not be necessary. */
3910 regcache_xfree (stop_registers
);
3912 /* NB: The copy goes through to the target picking up the value of
3913 all the registers. */
3914 stop_registers
= regcache_dup (get_current_regcache ());
3917 if (stop_stack_dummy
)
3919 /* Pop the empty frame that contains the stack dummy. POP_FRAME
3920 ends with a setting of the current frame, so we can use that
3922 frame_pop (get_current_frame ());
3923 /* Set stop_pc to what it was before we called the function.
3924 Can't rely on restore_inferior_status because that only gets
3925 called if we don't stop in the called function. */
3926 stop_pc
= read_pc ();
3927 select_frame (get_current_frame ());
3931 annotate_stopped ();
3932 if (!suppress_stop_observer
3933 && !(target_has_execution
3934 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3935 && last
.kind
!= TARGET_WAITKIND_EXITED
3936 && inferior_thread ()->step_multi
))
3938 if (!ptid_equal (inferior_ptid
, null_ptid
))
3939 observer_notify_normal_stop (inferior_thread ()->stop_bpstat
);
3941 observer_notify_normal_stop (NULL
);
3943 if (target_has_execution
3944 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
3945 && last
.kind
!= TARGET_WAITKIND_EXITED
)
3947 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3948 Delete any breakpoint that is to be deleted at the next stop. */
3949 breakpoint_auto_delete (inferior_thread ()->stop_bpstat
);
3952 set_running (pid_to_ptid (-1), 0);
3954 set_running (inferior_ptid
, 0);
3957 /* Look up the hook_stop and run it (CLI internally handles problem
3958 of stop_command's pre-hook not existing). */
3960 catch_errors (hook_stop_stub
, stop_command
,
3961 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
3966 hook_stop_stub (void *cmd
)
3968 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
3973 signal_stop_state (int signo
)
3975 /* Always stop on signals if we're just gaining control of the
3977 return signal_stop
[signo
] || stop_soon
!= NO_STOP_QUIETLY
;
3981 signal_print_state (int signo
)
3983 return signal_print
[signo
];
3987 signal_pass_state (int signo
)
3989 return signal_program
[signo
];
3993 signal_stop_update (int signo
, int state
)
3995 int ret
= signal_stop
[signo
];
3996 signal_stop
[signo
] = state
;
4001 signal_print_update (int signo
, int state
)
4003 int ret
= signal_print
[signo
];
4004 signal_print
[signo
] = state
;
4009 signal_pass_update (int signo
, int state
)
4011 int ret
= signal_program
[signo
];
4012 signal_program
[signo
] = state
;
4017 sig_print_header (void)
4019 printf_filtered (_("\
4020 Signal Stop\tPrint\tPass to program\tDescription\n"));
4024 sig_print_info (enum target_signal oursig
)
4026 char *name
= target_signal_to_name (oursig
);
4027 int name_padding
= 13 - strlen (name
);
4029 if (name_padding
<= 0)
4032 printf_filtered ("%s", name
);
4033 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
4034 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
4035 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
4036 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
4037 printf_filtered ("%s\n", target_signal_to_string (oursig
));
4040 /* Specify how various signals in the inferior should be handled. */
4043 handle_command (char *args
, int from_tty
)
4046 int digits
, wordlen
;
4047 int sigfirst
, signum
, siglast
;
4048 enum target_signal oursig
;
4051 unsigned char *sigs
;
4052 struct cleanup
*old_chain
;
4056 error_no_arg (_("signal to handle"));
4059 /* Allocate and zero an array of flags for which signals to handle. */
4061 nsigs
= (int) TARGET_SIGNAL_LAST
;
4062 sigs
= (unsigned char *) alloca (nsigs
);
4063 memset (sigs
, 0, nsigs
);
4065 /* Break the command line up into args. */
4067 argv
= buildargv (args
);
4072 old_chain
= make_cleanup_freeargv (argv
);
4074 /* Walk through the args, looking for signal oursigs, signal names, and
4075 actions. Signal numbers and signal names may be interspersed with
4076 actions, with the actions being performed for all signals cumulatively
4077 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
4079 while (*argv
!= NULL
)
4081 wordlen
= strlen (*argv
);
4082 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
4086 sigfirst
= siglast
= -1;
4088 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
4090 /* Apply action to all signals except those used by the
4091 debugger. Silently skip those. */
4094 siglast
= nsigs
- 1;
4096 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
4098 SET_SIGS (nsigs
, sigs
, signal_stop
);
4099 SET_SIGS (nsigs
, sigs
, signal_print
);
4101 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
4103 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4105 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
4107 SET_SIGS (nsigs
, sigs
, signal_print
);
4109 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
4111 SET_SIGS (nsigs
, sigs
, signal_program
);
4113 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
4115 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4117 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
4119 SET_SIGS (nsigs
, sigs
, signal_program
);
4121 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
4123 UNSET_SIGS (nsigs
, sigs
, signal_print
);
4124 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
4126 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
4128 UNSET_SIGS (nsigs
, sigs
, signal_program
);
4130 else if (digits
> 0)
4132 /* It is numeric. The numeric signal refers to our own
4133 internal signal numbering from target.h, not to host/target
4134 signal number. This is a feature; users really should be
4135 using symbolic names anyway, and the common ones like
4136 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
4138 sigfirst
= siglast
= (int)
4139 target_signal_from_command (atoi (*argv
));
4140 if ((*argv
)[digits
] == '-')
4143 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
4145 if (sigfirst
> siglast
)
4147 /* Bet he didn't figure we'd think of this case... */
4155 oursig
= target_signal_from_name (*argv
);
4156 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
4158 sigfirst
= siglast
= (int) oursig
;
4162 /* Not a number and not a recognized flag word => complain. */
4163 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
4167 /* If any signal numbers or symbol names were found, set flags for
4168 which signals to apply actions to. */
4170 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
4172 switch ((enum target_signal
) signum
)
4174 case TARGET_SIGNAL_TRAP
:
4175 case TARGET_SIGNAL_INT
:
4176 if (!allsigs
&& !sigs
[signum
])
4178 if (query ("%s is used by the debugger.\n\
4179 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal
) signum
)))
4185 printf_unfiltered (_("Not confirmed, unchanged.\n"));
4186 gdb_flush (gdb_stdout
);
4190 case TARGET_SIGNAL_0
:
4191 case TARGET_SIGNAL_DEFAULT
:
4192 case TARGET_SIGNAL_UNKNOWN
:
4193 /* Make sure that "all" doesn't print these. */
4204 target_notice_signals (inferior_ptid
);
4208 /* Show the results. */
4209 sig_print_header ();
4210 for (signum
= 0; signum
< nsigs
; signum
++)
4214 sig_print_info (signum
);
4219 do_cleanups (old_chain
);
4223 xdb_handle_command (char *args
, int from_tty
)
4226 struct cleanup
*old_chain
;
4228 /* Break the command line up into args. */
4230 argv
= buildargv (args
);
4235 old_chain
= make_cleanup_freeargv (argv
);
4236 if (argv
[1] != (char *) NULL
)
4241 bufLen
= strlen (argv
[0]) + 20;
4242 argBuf
= (char *) xmalloc (bufLen
);
4246 enum target_signal oursig
;
4248 oursig
= target_signal_from_name (argv
[0]);
4249 memset (argBuf
, 0, bufLen
);
4250 if (strcmp (argv
[1], "Q") == 0)
4251 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4254 if (strcmp (argv
[1], "s") == 0)
4256 if (!signal_stop
[oursig
])
4257 sprintf (argBuf
, "%s %s", argv
[0], "stop");
4259 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
4261 else if (strcmp (argv
[1], "i") == 0)
4263 if (!signal_program
[oursig
])
4264 sprintf (argBuf
, "%s %s", argv
[0], "pass");
4266 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
4268 else if (strcmp (argv
[1], "r") == 0)
4270 if (!signal_print
[oursig
])
4271 sprintf (argBuf
, "%s %s", argv
[0], "print");
4273 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
4279 handle_command (argBuf
, from_tty
);
4281 printf_filtered (_("Invalid signal handling flag.\n"));
4286 do_cleanups (old_chain
);
4289 /* Print current contents of the tables set by the handle command.
4290 It is possible we should just be printing signals actually used
4291 by the current target (but for things to work right when switching
4292 targets, all signals should be in the signal tables). */
4295 signals_info (char *signum_exp
, int from_tty
)
4297 enum target_signal oursig
;
4298 sig_print_header ();
4302 /* First see if this is a symbol name. */
4303 oursig
= target_signal_from_name (signum_exp
);
4304 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
4306 /* No, try numeric. */
4308 target_signal_from_command (parse_and_eval_long (signum_exp
));
4310 sig_print_info (oursig
);
4314 printf_filtered ("\n");
4315 /* These ugly casts brought to you by the native VAX compiler. */
4316 for (oursig
= TARGET_SIGNAL_FIRST
;
4317 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
4318 oursig
= (enum target_signal
) ((int) oursig
+ 1))
4322 if (oursig
!= TARGET_SIGNAL_UNKNOWN
4323 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
4324 sig_print_info (oursig
);
4327 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
4330 struct inferior_status
4332 enum target_signal stop_signal
;
4336 int stop_stack_dummy
;
4337 int stopped_by_random_signal
;
4338 int stepping_over_breakpoint
;
4339 CORE_ADDR step_range_start
;
4340 CORE_ADDR step_range_end
;
4341 struct frame_id step_frame_id
;
4342 enum step_over_calls_kind step_over_calls
;
4343 CORE_ADDR step_resume_break_address
;
4344 int stop_after_trap
;
4347 /* These are here because if call_function_by_hand has written some
4348 registers and then decides to call error(), we better not have changed
4350 struct regcache
*registers
;
4352 /* A frame unique identifier. */
4353 struct frame_id selected_frame_id
;
4355 int breakpoint_proceeded
;
4356 int restore_stack_info
;
4357 int proceed_to_finish
;
4361 write_inferior_status_register (struct inferior_status
*inf_status
, int regno
,
4364 int size
= register_size (current_gdbarch
, regno
);
4365 void *buf
= alloca (size
);
4366 store_signed_integer (buf
, size
, val
);
4367 regcache_raw_write (inf_status
->registers
, regno
, buf
);
4370 /* Save all of the information associated with the inferior<==>gdb
4371 connection. INF_STATUS is a pointer to a "struct inferior_status"
4372 (defined in inferior.h). */
4374 struct inferior_status
*
4375 save_inferior_status (int restore_stack_info
)
4377 struct inferior_status
*inf_status
= XMALLOC (struct inferior_status
);
4378 struct thread_info
*tp
= inferior_thread ();
4380 inf_status
->stop_signal
= tp
->stop_signal
;
4381 inf_status
->stop_pc
= stop_pc
;
4382 inf_status
->stop_step
= tp
->stop_step
;
4383 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
4384 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
4385 inf_status
->stepping_over_breakpoint
= tp
->trap_expected
;
4386 inf_status
->step_range_start
= tp
->step_range_start
;
4387 inf_status
->step_range_end
= tp
->step_range_end
;
4388 inf_status
->step_frame_id
= tp
->step_frame_id
;
4389 inf_status
->step_over_calls
= tp
->step_over_calls
;
4390 inf_status
->stop_after_trap
= stop_after_trap
;
4391 inf_status
->stop_soon
= stop_soon
;
4392 /* Save original bpstat chain here; replace it with copy of chain.
4393 If caller's caller is walking the chain, they'll be happier if we
4394 hand them back the original chain when restore_inferior_status is
4396 inf_status
->stop_bpstat
= tp
->stop_bpstat
;
4397 tp
->stop_bpstat
= bpstat_copy (tp
->stop_bpstat
);
4398 inf_status
->breakpoint_proceeded
= breakpoint_proceeded
;
4399 inf_status
->restore_stack_info
= restore_stack_info
;
4400 inf_status
->proceed_to_finish
= tp
->proceed_to_finish
;
4402 inf_status
->registers
= regcache_dup (get_current_regcache ());
4404 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
4409 restore_selected_frame (void *args
)
4411 struct frame_id
*fid
= (struct frame_id
*) args
;
4412 struct frame_info
*frame
;
4414 frame
= frame_find_by_id (*fid
);
4416 /* If inf_status->selected_frame_id is NULL, there was no previously
4420 warning (_("Unable to restore previously selected frame."));
4424 select_frame (frame
);
4430 restore_inferior_status (struct inferior_status
*inf_status
)
4432 struct thread_info
*tp
= inferior_thread ();
4434 tp
->stop_signal
= inf_status
->stop_signal
;
4435 stop_pc
= inf_status
->stop_pc
;
4436 tp
->stop_step
= inf_status
->stop_step
;
4437 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
4438 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
4439 tp
->trap_expected
= inf_status
->stepping_over_breakpoint
;
4440 tp
->step_range_start
= inf_status
->step_range_start
;
4441 tp
->step_range_end
= inf_status
->step_range_end
;
4442 tp
->step_frame_id
= inf_status
->step_frame_id
;
4443 tp
->step_over_calls
= inf_status
->step_over_calls
;
4444 stop_after_trap
= inf_status
->stop_after_trap
;
4445 stop_soon
= inf_status
->stop_soon
;
4446 bpstat_clear (&tp
->stop_bpstat
);
4447 tp
->stop_bpstat
= inf_status
->stop_bpstat
;
4448 breakpoint_proceeded
= inf_status
->breakpoint_proceeded
;
4449 tp
->proceed_to_finish
= inf_status
->proceed_to_finish
;
4451 /* The inferior can be gone if the user types "print exit(0)"
4452 (and perhaps other times). */
4453 if (target_has_execution
)
4454 /* NB: The register write goes through to the target. */
4455 regcache_cpy (get_current_regcache (), inf_status
->registers
);
4456 regcache_xfree (inf_status
->registers
);
4458 /* FIXME: If we are being called after stopping in a function which
4459 is called from gdb, we should not be trying to restore the
4460 selected frame; it just prints a spurious error message (The
4461 message is useful, however, in detecting bugs in gdb (like if gdb
4462 clobbers the stack)). In fact, should we be restoring the
4463 inferior status at all in that case? . */
4465 if (target_has_stack
&& inf_status
->restore_stack_info
)
4467 /* The point of catch_errors is that if the stack is clobbered,
4468 walking the stack might encounter a garbage pointer and
4469 error() trying to dereference it. */
4471 (restore_selected_frame
, &inf_status
->selected_frame_id
,
4472 "Unable to restore previously selected frame:\n",
4473 RETURN_MASK_ERROR
) == 0)
4474 /* Error in restoring the selected frame. Select the innermost
4476 select_frame (get_current_frame ());
4484 do_restore_inferior_status_cleanup (void *sts
)
4486 restore_inferior_status (sts
);
4490 make_cleanup_restore_inferior_status (struct inferior_status
*inf_status
)
4492 return make_cleanup (do_restore_inferior_status_cleanup
, inf_status
);
4496 discard_inferior_status (struct inferior_status
*inf_status
)
4498 /* See save_inferior_status for info on stop_bpstat. */
4499 bpstat_clear (&inf_status
->stop_bpstat
);
4500 regcache_xfree (inf_status
->registers
);
4505 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
4507 struct target_waitstatus last
;
4510 get_last_target_status (&last_ptid
, &last
);
4512 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
4515 if (!ptid_equal (last_ptid
, pid
))
4518 *child_pid
= last
.value
.related_pid
;
4523 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
4525 struct target_waitstatus last
;
4528 get_last_target_status (&last_ptid
, &last
);
4530 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
4533 if (!ptid_equal (last_ptid
, pid
))
4536 *child_pid
= last
.value
.related_pid
;
4541 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
4543 struct target_waitstatus last
;
4546 get_last_target_status (&last_ptid
, &last
);
4548 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
4551 if (!ptid_equal (last_ptid
, pid
))
4554 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
4558 /* Oft used ptids */
4560 ptid_t minus_one_ptid
;
4562 /* Create a ptid given the necessary PID, LWP, and TID components. */
4565 ptid_build (int pid
, long lwp
, long tid
)
4575 /* Create a ptid from just a pid. */
4578 pid_to_ptid (int pid
)
4580 return ptid_build (pid
, 0, 0);
4583 /* Fetch the pid (process id) component from a ptid. */
4586 ptid_get_pid (ptid_t ptid
)
4591 /* Fetch the lwp (lightweight process) component from a ptid. */
4594 ptid_get_lwp (ptid_t ptid
)
4599 /* Fetch the tid (thread id) component from a ptid. */
4602 ptid_get_tid (ptid_t ptid
)
4607 /* ptid_equal() is used to test equality of two ptids. */
4610 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
4612 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
4613 && ptid1
.tid
== ptid2
.tid
);
4616 /* restore_inferior_ptid() will be used by the cleanup machinery
4617 to restore the inferior_ptid value saved in a call to
4618 save_inferior_ptid(). */
4621 restore_inferior_ptid (void *arg
)
4623 ptid_t
*saved_ptid_ptr
= arg
;
4624 inferior_ptid
= *saved_ptid_ptr
;
4628 /* Save the value of inferior_ptid so that it may be restored by a
4629 later call to do_cleanups(). Returns the struct cleanup pointer
4630 needed for later doing the cleanup. */
4633 save_inferior_ptid (void)
4635 ptid_t
*saved_ptid_ptr
;
4637 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
4638 *saved_ptid_ptr
= inferior_ptid
;
4639 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
4644 static int non_stop_1
= 0;
4647 set_non_stop (char *args
, int from_tty
,
4648 struct cmd_list_element
*c
)
4650 if (target_has_execution
)
4652 non_stop_1
= non_stop
;
4653 error (_("Cannot change this setting while the inferior is running."));
4656 non_stop
= non_stop_1
;
4660 show_non_stop (struct ui_file
*file
, int from_tty
,
4661 struct cmd_list_element
*c
, const char *value
)
4663 fprintf_filtered (file
,
4664 _("Controlling the inferior in non-stop mode is %s.\n"),
4670 _initialize_infrun (void)
4674 struct cmd_list_element
*c
;
4676 add_info ("signals", signals_info
, _("\
4677 What debugger does when program gets various signals.\n\
4678 Specify a signal as argument to print info on that signal only."));
4679 add_info_alias ("handle", "signals", 0);
4681 add_com ("handle", class_run
, handle_command
, _("\
4682 Specify how to handle a signal.\n\
4683 Args are signals and actions to apply to those signals.\n\
4684 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4685 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4686 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4687 The special arg \"all\" is recognized to mean all signals except those\n\
4688 used by the debugger, typically SIGTRAP and SIGINT.\n\
4689 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4690 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4691 Stop means reenter debugger if this signal happens (implies print).\n\
4692 Print means print a message if this signal happens.\n\
4693 Pass means let program see this signal; otherwise program doesn't know.\n\
4694 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4695 Pass and Stop may be combined."));
4698 add_com ("lz", class_info
, signals_info
, _("\
4699 What debugger does when program gets various signals.\n\
4700 Specify a signal as argument to print info on that signal only."));
4701 add_com ("z", class_run
, xdb_handle_command
, _("\
4702 Specify how to handle a signal.\n\
4703 Args are signals and actions to apply to those signals.\n\
4704 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4705 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4706 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4707 The special arg \"all\" is recognized to mean all signals except those\n\
4708 used by the debugger, typically SIGTRAP and SIGINT.\n\
4709 Recognized actions include \"s\" (toggles between stop and nostop), \n\
4710 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4711 nopass), \"Q\" (noprint)\n\
4712 Stop means reenter debugger if this signal happens (implies print).\n\
4713 Print means print a message if this signal happens.\n\
4714 Pass means let program see this signal; otherwise program doesn't know.\n\
4715 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4716 Pass and Stop may be combined."));
4720 stop_command
= add_cmd ("stop", class_obscure
,
4721 not_just_help_class_command
, _("\
4722 There is no `stop' command, but you can set a hook on `stop'.\n\
4723 This allows you to set a list of commands to be run each time execution\n\
4724 of the program stops."), &cmdlist
);
4726 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
4727 Set inferior debugging."), _("\
4728 Show inferior debugging."), _("\
4729 When non-zero, inferior specific debugging is enabled."),
4732 &setdebuglist
, &showdebuglist
);
4734 add_setshow_boolean_cmd ("displaced", class_maintenance
, &debug_displaced
, _("\
4735 Set displaced stepping debugging."), _("\
4736 Show displaced stepping debugging."), _("\
4737 When non-zero, displaced stepping specific debugging is enabled."),
4739 show_debug_displaced
,
4740 &setdebuglist
, &showdebuglist
);
4742 add_setshow_boolean_cmd ("non-stop", no_class
,
4744 Set whether gdb controls the inferior in non-stop mode."), _("\
4745 Show whether gdb controls the inferior in non-stop mode."), _("\
4746 When debugging a multi-threaded program and this setting is\n\
4747 off (the default, also called all-stop mode), when one thread stops\n\
4748 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
4749 all other threads in the program while you interact with the thread of\n\
4750 interest. When you continue or step a thread, you can allow the other\n\
4751 threads to run, or have them remain stopped, but while you inspect any\n\
4752 thread's state, all threads stop.\n\
4754 In non-stop mode, when one thread stops, other threads can continue\n\
4755 to run freely. You'll be able to step each thread independently,\n\
4756 leave it stopped or free to run as needed."),
4762 numsigs
= (int) TARGET_SIGNAL_LAST
;
4763 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
4764 signal_print
= (unsigned char *)
4765 xmalloc (sizeof (signal_print
[0]) * numsigs
);
4766 signal_program
= (unsigned char *)
4767 xmalloc (sizeof (signal_program
[0]) * numsigs
);
4768 for (i
= 0; i
< numsigs
; i
++)
4771 signal_print
[i
] = 1;
4772 signal_program
[i
] = 1;
4775 /* Signals caused by debugger's own actions
4776 should not be given to the program afterwards. */
4777 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
4778 signal_program
[TARGET_SIGNAL_INT
] = 0;
4780 /* Signals that are not errors should not normally enter the debugger. */
4781 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
4782 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
4783 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
4784 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
4785 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
4786 signal_print
[TARGET_SIGNAL_PROF
] = 0;
4787 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
4788 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
4789 signal_stop
[TARGET_SIGNAL_IO
] = 0;
4790 signal_print
[TARGET_SIGNAL_IO
] = 0;
4791 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
4792 signal_print
[TARGET_SIGNAL_POLL
] = 0;
4793 signal_stop
[TARGET_SIGNAL_URG
] = 0;
4794 signal_print
[TARGET_SIGNAL_URG
] = 0;
4795 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
4796 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
4798 /* These signals are used internally by user-level thread
4799 implementations. (See signal(5) on Solaris.) Like the above
4800 signals, a healthy program receives and handles them as part of
4801 its normal operation. */
4802 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
4803 signal_print
[TARGET_SIGNAL_LWP
] = 0;
4804 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
4805 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
4806 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
4807 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
4809 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
4810 &stop_on_solib_events
, _("\
4811 Set stopping for shared library events."), _("\
4812 Show stopping for shared library events."), _("\
4813 If nonzero, gdb will give control to the user when the dynamic linker\n\
4814 notifies gdb of shared library events. The most common event of interest\n\
4815 to the user would be loading/unloading of a new library."),
4817 show_stop_on_solib_events
,
4818 &setlist
, &showlist
);
4820 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
4821 follow_fork_mode_kind_names
,
4822 &follow_fork_mode_string
, _("\
4823 Set debugger response to a program call of fork or vfork."), _("\
4824 Show debugger response to a program call of fork or vfork."), _("\
4825 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4826 parent - the original process is debugged after a fork\n\
4827 child - the new process is debugged after a fork\n\
4828 The unfollowed process will continue to run.\n\
4829 By default, the debugger will follow the parent process."),
4831 show_follow_fork_mode_string
,
4832 &setlist
, &showlist
);
4834 add_setshow_enum_cmd ("scheduler-locking", class_run
,
4835 scheduler_enums
, &scheduler_mode
, _("\
4836 Set mode for locking scheduler during execution."), _("\
4837 Show mode for locking scheduler during execution."), _("\
4838 off == no locking (threads may preempt at any time)\n\
4839 on == full locking (no thread except the current thread may run)\n\
4840 step == scheduler locked during every single-step operation.\n\
4841 In this mode, no other thread may run during a step command.\n\
4842 Other threads may run while stepping over a function call ('next')."),
4843 set_schedlock_func
, /* traps on target vector */
4844 show_scheduler_mode
,
4845 &setlist
, &showlist
);
4847 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
4848 Set mode of the step operation."), _("\
4849 Show mode of the step operation."), _("\
4850 When set, doing a step over a function without debug line information\n\
4851 will stop at the first instruction of that function. Otherwise, the\n\
4852 function is skipped and the step command stops at a different source line."),
4854 show_step_stop_if_no_debug
,
4855 &setlist
, &showlist
);
4857 add_setshow_boolean_cmd ("can-use-displaced-stepping", class_maintenance
,
4858 &can_use_displaced_stepping
, _("\
4859 Set debugger's willingness to use displaced stepping."), _("\
4860 Show debugger's willingness to use displaced stepping."), _("\
4861 If zero, gdb will not use displaced stepping to step over\n\
4862 breakpoints, even if such is supported by the target."),
4864 show_can_use_displaced_stepping
,
4865 &maintenance_set_cmdlist
,
4866 &maintenance_show_cmdlist
);
4868 /* ptid initializations */
4869 null_ptid
= ptid_build (0, 0, 0);
4870 minus_one_ptid
= ptid_build (-1, 0, 0);
4871 inferior_ptid
= null_ptid
;
4872 target_last_wait_ptid
= minus_one_ptid
;
4873 displaced_step_ptid
= null_ptid
;
4875 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);