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;
1108 tp->proceed_to_finish = 0;
1110 /* Discard any remaining commands or status from previous
1112 bpstat_clear (&tp->stop_bpstat);
1115 stop_after_trap = 0;
1116 stop_soon = NO_STOP_QUIETLY;
1117 breakpoint_proceeded = 1; /* We're about to proceed... */
1121 regcache_xfree (stop_registers);
1122 stop_registers = NULL;
1126 /* This should be suitable for any targets that support threads. */
1129 prepare_to_proceed (int step)
1132 struct target_waitstatus wait_status;
1134 /* Get the last target status returned by target_wait(). */
1135 get_last_target_status (&wait_ptid, &wait_status);
1137 /* Make sure we were stopped at a breakpoint. */
1138 if (wait_status.kind != TARGET_WAITKIND_STOPPED
1139 || wait_status.value.sig != TARGET_SIGNAL_TRAP)
1144 /* Switched over from WAIT_PID. */
1145 if (!ptid_equal (wait_ptid, minus_one_ptid)
1146 && !ptid_equal (inferior_ptid, wait_ptid))
1148 struct regcache *regcache = get_thread_regcache (wait_ptid);
1150 if (breakpoint_here_p (regcache_read_pc (regcache)))
1152 /* If stepping, remember current thread to switch back to. */
1154 deferred_step_ptid = inferior_ptid;
1156 /* Switch back to WAIT_PID thread. */
1157 switch_to_thread (wait_ptid);
1159 /* We return 1 to indicate that there is a breakpoint here,
1160 so we need to step over it before continuing to avoid
1161 hitting it straight away. */
1169 /* Basic routine for continuing the program in various fashions.
1171 ADDR is the address to resume at, or -1 for resume where stopped.
1172 SIGGNAL is the signal to give it, or 0 for none,
1173 or -1 for act according to how it stopped.
1174 STEP is nonzero if should trap after one instruction.
1175 -1 means return after that and print nothing.
1176 You should probably set various step_... variables
1177 before calling here, if you are stepping.
1179 You should call clear_proceed_status before calling proceed. */
1182 proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
1184 struct regcache *regcache = get_current_regcache ();
1185 struct gdbarch *gdbarch = get_regcache_arch (regcache);
1186 struct thread_info *tp;
1187 CORE_ADDR pc = regcache_read_pc (regcache);
1189 enum target_signal stop_signal;
1192 step_start_function = find_pc_function (pc);
1194 stop_after_trap = 1;
1196 if (addr == (CORE_ADDR) -1)
1198 if (pc == stop_pc && breakpoint_here_p (pc))
1199 /* There is a breakpoint at the address we will resume at,
1200 step one instruction before inserting breakpoints so that
1201 we do not stop right away (and report a second hit at this
1204 else if (gdbarch_single_step_through_delay_p (gdbarch)
1205 && gdbarch_single_step_through_delay (gdbarch,
1206 get_current_frame ()))
1207 /* We stepped onto an instruction that needs to be stepped
1208 again before re-inserting the breakpoint, do so. */
1213 regcache_write_pc (regcache, addr);
1217 fprintf_unfiltered (gdb_stdlog,
1218 "infrun: proceed (addr=0x%s, signal=%d, step=%d)\n",
1219 paddr_nz (addr), siggnal, step);
1222 /* In non-stop, each thread is handled individually. The context
1223 must already be set to the right thread here. */
1227 /* In a multi-threaded task we may select another thread and
1228 then continue or step.
1230 But if the old thread was stopped at a breakpoint, it will
1231 immediately cause another breakpoint stop without any
1232 execution (i.e. it will report a breakpoint hit incorrectly).
1233 So we must step over it first.
1235 prepare_to_proceed checks the current thread against the
1236 thread that reported the most recent event. If a step-over
1237 is required it returns TRUE and sets the current thread to
1239 if (prepare_to_proceed (step))
1243 /* prepare_to_proceed may change the current thread. */
1244 tp = inferior_thread ();
1248 tp->trap_expected = 1;
1249 /* If displaced stepping is enabled, we can step over the
1250 breakpoint without hitting it, so leave all breakpoints
1251 inserted. Otherwise we need to disable all breakpoints, step
1252 one instruction, and then re-add them when that step is
1254 if (!use_displaced_stepping (gdbarch))
1255 remove_breakpoints ();
1258 /* We can insert breakpoints if we're not trying to step over one,
1259 or if we are stepping over one but we're using displaced stepping
1261 if (! tp->trap_expected || use_displaced_stepping (gdbarch))
1262 insert_breakpoints ();
1266 /* Pass the last stop signal to the thread we're resuming,
1267 irrespective of whether the current thread is the thread that
1268 got the last event or not. This was historically GDB's
1269 behaviour before keeping a stop_signal per thread. */
1271 struct thread_info *last_thread;
1273 struct target_waitstatus last_status;
1275 get_last_target_status (&last_ptid, &last_status);
1276 if (!ptid_equal (inferior_ptid, last_ptid)
1277 && !ptid_equal (last_ptid, null_ptid)
1278 && !ptid_equal (last_ptid, minus_one_ptid))
1280 last_thread = find_thread_pid (last_ptid);
1283 tp->stop_signal = last_thread->stop_signal;
1284 last_thread->stop_signal = TARGET_SIGNAL_0;
1289 if (siggnal != TARGET_SIGNAL_DEFAULT)
1290 tp->stop_signal = siggnal;
1291 /* If this signal should not be seen by program,
1292 give it zero. Used for debugging signals. */
1293 else if (!signal_program[tp->stop_signal])
1294 tp->stop_signal = TARGET_SIGNAL_0;
1296 annotate_starting ();
1298 /* Make sure that output from GDB appears before output from the
1300 gdb_flush (gdb_stdout);
1302 /* Refresh prev_pc value just prior to resuming. This used to be
1303 done in stop_stepping, however, setting prev_pc there did not handle
1304 scenarios such as inferior function calls or returning from
1305 a function via the return command. In those cases, the prev_pc
1306 value was not set properly for subsequent commands. The prev_pc value
1307 is used to initialize the starting line number in the ecs. With an
1308 invalid value, the gdb next command ends up stopping at the position
1309 represented by the next line table entry past our start position.
1310 On platforms that generate one line table entry per line, this
1311 is not a problem. However, on the ia64, the compiler generates
1312 extraneous line table entries that do not increase the line number.
1313 When we issue the gdb next command on the ia64 after an inferior call
1314 or a return command, we often end up a few instructions forward, still
1315 within the original line we started.
1317 An attempt was made to have init_execution_control_state () refresh
1318 the prev_pc value before calculating the line number. This approach
1319 did not work because on platforms that use ptrace, the pc register
1320 cannot be read unless the inferior is stopped. At that point, we
1321 are not guaranteed the inferior is stopped and so the regcache_read_pc ()
1322 call can fail. Setting the prev_pc value here ensures the value is
1323 updated correctly when the inferior is stopped. */
1324 tp->prev_pc = regcache_read_pc (get_current_regcache ());
1326 /* Fill in with reasonable starting values. */
1327 init_thread_stepping_state (tp);
1329 /* Reset to normal state. */
1330 init_infwait_state ();
1332 /* Resume inferior. */
1333 resume (oneproc || step || bpstat_should_step (), tp->stop_signal);
1335 /* Wait for it to stop (if not standalone)
1336 and in any case decode why it stopped, and act accordingly. */
1337 /* Do this only if we are not using the event loop, or if the target
1338 does not support asynchronous execution. */
1339 if (!target_can_async_p ())
1341 wait_for_inferior (0);
1347 /* Start remote-debugging of a machine over a serial link. */
1350 start_remote (int from_tty)
1352 init_wait_for_inferior ();
1353 stop_soon = STOP_QUIETLY_REMOTE;
1355 /* Always go on waiting for the target, regardless of the mode. */
1356 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1357 indicate to wait_for_inferior that a target should timeout if
1358 nothing is returned (instead of just blocking). Because of this,
1359 targets expecting an immediate response need to, internally, set
1360 things up so that the target_wait() is forced to eventually
1362 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1363 differentiate to its caller what the state of the target is after
1364 the initial open has been performed. Here we're assuming that
1365 the target has stopped. It should be possible to eventually have
1366 target_open() return to the caller an indication that the target
1367 is currently running and GDB state should be set to the same as
1368 for an async run. */
1369 wait_for_inferior (0);
1371 /* Now that the inferior has stopped, do any bookkeeping like
1372 loading shared libraries. We want to do this before normal_stop,
1373 so that the displayed frame is up to date. */
1374 post_create_inferior (¤t_target, from_tty);
1379 /* Initialize static vars when a new inferior begins. */
1382 init_wait_for_inferior (void)
1384 /* These are meaningless until the first time through wait_for_inferior. */
1386 breakpoint_init_inferior (inf_starting);
1388 /* The first resume is not following a fork/vfork/exec. */
1389 pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
1391 clear_proceed_status ();
1393 stepping_past_singlestep_breakpoint = 0;
1394 deferred_step_ptid = null_ptid;
1396 target_last_wait_ptid = minus_one_ptid;
1398 previous_inferior_ptid = null_ptid;
1399 init_infwait_state ();
1401 displaced_step_clear ();
1405 /* This enum encodes possible reasons for doing a target_wait, so that
1406 wfi can call target_wait in one place. (Ultimately the call will be
1407 moved out of the infinite loop entirely.) */
1411 infwait_normal_state,
1412 infwait_thread_hop_state,
1413 infwait_step_watch_state,
1414 infwait_nonstep_watch_state
1417 /* Why did the inferior stop? Used to print the appropriate messages
1418 to the interface from within handle_inferior_event(). */
1419 enum inferior_stop_reason
1421 /* Step, next, nexti, stepi finished. */
1423 /* Inferior terminated by signal. */
1425 /* Inferior exited. */
1427 /* Inferior received signal, and user asked to be notified. */
1431 /* The PTID we'll do a target_wait on.*/
1434 /* Current inferior wait state. */
1435 enum infwait_states infwait_state;
1437 /* Data to be passed around while handling an event. This data is
1438 discarded between events. */
1439 struct execution_control_state
1442 /* The thread that got the event, if this was a thread event; NULL
1444 struct thread_info *event_thread;
1446 struct target_waitstatus ws;
1448 CORE_ADDR stop_func_start;
1449 CORE_ADDR stop_func_end;
1450 char *stop_func_name;
1451 int new_thread_event;
1455 void init_execution_control_state (struct execution_control_state *ecs);
1457 void handle_inferior_event (struct execution_control_state *ecs);
1459 static void step_into_function (struct execution_control_state *ecs);
1460 static void insert_step_resume_breakpoint_at_frame (struct frame_info *step_frame);
1461 static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
1462 static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
1463 struct frame_id sr_id);
1464 static void insert_longjmp_resume_breakpoint (CORE_ADDR);
1466 static void stop_stepping (struct execution_control_state *ecs);
1467 static void prepare_to_wait (struct execution_control_state *ecs);
1468 static void keep_going (struct execution_control_state *ecs);
1469 static void print_stop_reason (enum inferior_stop_reason stop_reason,
1472 /* Callback for iterate_over_threads. */
1475 delete_step_resume_breakpoint_callback (struct thread_info *info, void *data)
1477 if (is_exited (info->ptid))
1480 delete_step_resume_breakpoint (info);
1484 /* In all-stop, delete the step resume breakpoint of any thread that
1485 had one. In non-stop, delete the step resume breakpoint of the
1486 thread that just stopped. */
1489 delete_step_thread_step_resume_breakpoint (void)
1491 if (!target_has_execution
1492 || ptid_equal (inferior_ptid, null_ptid))
1493 /* If the inferior has exited, we have already deleted the step
1494 resume breakpoints out of GDB's lists. */
1499 /* If in non-stop mode, only delete the step-resume or
1500 longjmp-resume breakpoint of the thread that just stopped
1502 struct thread_info *tp = inferior_thread ();
1503 delete_step_resume_breakpoint (tp);
1506 /* In all-stop mode, delete all step-resume and longjmp-resume
1507 breakpoints of any thread that had them. */
1508 iterate_over_threads (delete_step_resume_breakpoint_callback, NULL);
1511 /* A cleanup wrapper. */
1514 delete_step_thread_step_resume_breakpoint_cleanup (void *arg)
1516 delete_step_thread_step_resume_breakpoint ();
1519 /* Wait for control to return from inferior to debugger.
1521 If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
1522 as if they were SIGTRAP signals. This can be useful during
1523 the startup sequence on some targets such as HP/UX, where
1524 we receive an EXEC event instead of the expected SIGTRAP.
1526 If inferior gets a signal, we may decide to start it up again
1527 instead of returning. That is why there is a loop in this function.
1528 When this function actually returns it means the inferior
1529 should be left stopped and GDB should read more commands. */
1532 wait_for_inferior (int treat_exec_as_sigtrap)
1534 struct cleanup *old_cleanups;
1535 struct execution_control_state ecss;
1536 struct execution_control_state *ecs;
1540 (gdb_stdlog, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
1541 treat_exec_as_sigtrap);
1544 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup, NULL);
1547 memset (ecs, 0, sizeof (*ecs));
1549 overlay_cache_invalid = 1;
1551 /* We'll update this if & when we switch to a new thread. */
1552 previous_inferior_ptid = inferior_ptid;
1554 /* We have to invalidate the registers BEFORE calling target_wait
1555 because they can be loaded from the target while in target_wait.
1556 This makes remote debugging a bit more efficient for those
1557 targets that provide critical registers as part of their normal
1558 status mechanism. */
1560 registers_changed ();
1564 if (deprecated_target_wait_hook)
1565 ecs->ptid = deprecated_target_wait_hook (waiton_ptid, &ecs->ws);
1567 ecs->ptid = target_wait (waiton_ptid, &ecs->ws);
1569 ecs->event_thread = find_thread_pid (ecs->ptid);
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 ecs->event_thread = find_thread_pid (ecs->ptid);
1648 /* Now figure out what to do with the result of the result. */
1649 handle_inferior_event (ecs);
1651 if (!ecs->wait_some_more)
1653 delete_step_thread_step_resume_breakpoint ();
1655 if (stop_soon == NO_STOP_QUIETLY)
1658 if (step_multi && stop_step)
1659 inferior_event_handler (INF_EXEC_CONTINUE, NULL);
1661 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
1664 /* Revert thread and frame. */
1665 do_cleanups (old_chain);
1667 /* If the inferior was in sync execution mode, and now isn't,
1668 restore the prompt. */
1669 if (was_sync && !sync_execution)
1670 display_gdb_prompt (0);
1673 /* Prepare an execution control state for looping through a
1674 wait_for_inferior-type loop. */
1677 init_execution_control_state (struct execution_control_state *ecs)
1679 ecs->random_signal = 0;
1682 /* Clear context switchable stepping state. */
1685 init_thread_stepping_state (struct thread_info *tss)
1687 struct symtab_and_line sal;
1689 tss->stepping_over_breakpoint = 0;
1690 tss->step_after_step_resume_breakpoint = 0;
1691 tss->stepping_through_solib_after_catch = 0;
1692 tss->stepping_through_solib_catchpoints = NULL;
1694 sal = find_pc_line (tss->prev_pc, 0);
1695 tss->current_line = sal.line;
1696 tss->current_symtab = sal.symtab;
1699 /* Return the cached copy of the last pid/waitstatus returned by
1700 target_wait()/deprecated_target_wait_hook(). The data is actually
1701 cached by handle_inferior_event(), which gets called immediately
1702 after target_wait()/deprecated_target_wait_hook(). */
1705 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
1707 *ptidp = target_last_wait_ptid;
1708 *status = target_last_waitstatus;
1712 nullify_last_target_wait_ptid (void)
1714 target_last_wait_ptid = minus_one_ptid;
1717 /* Switch thread contexts, maintaining "infrun state". */
1720 context_switch (ptid_t ptid)
1722 /* Caution: it may happen that the new thread (or the old one!)
1723 is not in the thread list. In this case we must not attempt
1724 to "switch context", or we run the risk that our context may
1725 be lost. This may happen as a result of the target module
1726 mishandling thread creation. */
1730 fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
1731 target_pid_to_str (inferior_ptid));
1732 fprintf_unfiltered (gdb_stdlog, "to %s\n",
1733 target_pid_to_str (ptid));
1736 if (in_thread_list (inferior_ptid) && in_thread_list (ptid))
1737 { /* Perform infrun state context switch: */
1738 /* Save infrun state for the old thread. */
1739 save_infrun_state (inferior_ptid,
1740 cmd_continuation, intermediate_continuation,
1744 /* Load infrun state for the new thread. */
1745 load_infrun_state (ptid,
1746 &cmd_continuation, &intermediate_continuation,
1751 switch_to_thread (ptid);
1754 /* Context switch to thread PTID. */
1756 context_switch_to (ptid_t ptid)
1758 ptid_t current_ptid = inferior_ptid;
1760 /* Context switch to the new thread. */
1761 if (!ptid_equal (ptid, inferior_ptid))
1763 context_switch (ptid);
1765 return current_ptid;
1769 adjust_pc_after_break (struct execution_control_state *ecs)
1771 struct regcache *regcache;
1772 struct gdbarch *gdbarch;
1773 CORE_ADDR breakpoint_pc;
1775 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
1776 we aren't, just return.
1778 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
1779 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
1780 implemented by software breakpoints should be handled through the normal
1783 NOTE drow/2004-01-31: On some targets, breakpoints may generate
1784 different signals (SIGILL or SIGEMT for instance), but it is less
1785 clear where the PC is pointing afterwards. It may not match
1786 gdbarch_decr_pc_after_break. I don't know any specific target that
1787 generates these signals at breakpoints (the code has been in GDB since at
1788 least 1992) so I can not guess how to handle them here.
1790 In earlier versions of GDB, a target with
1791 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
1792 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
1793 target with both of these set in GDB history, and it seems unlikely to be
1794 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
1796 if (ecs->ws.kind != TARGET_WAITKIND_STOPPED)
1799 if (ecs->ws.value.sig != TARGET_SIGNAL_TRAP)
1802 /* If this target does not decrement the PC after breakpoints, then
1803 we have nothing to do. */
1804 regcache = get_thread_regcache (ecs->ptid);
1805 gdbarch = get_regcache_arch (regcache);
1806 if (gdbarch_decr_pc_after_break (gdbarch) == 0)
1809 /* Find the location where (if we've hit a breakpoint) the
1810 breakpoint would be. */
1811 breakpoint_pc = regcache_read_pc (regcache)
1812 - gdbarch_decr_pc_after_break (gdbarch);
1814 /* Check whether there actually is a software breakpoint inserted
1815 at that location. */
1816 if (software_breakpoint_inserted_here_p (breakpoint_pc))
1818 /* When using hardware single-step, a SIGTRAP is reported for both
1819 a completed single-step and a software breakpoint. Need to
1820 differentiate between the two, as the latter needs adjusting
1821 but the former does not.
1823 The SIGTRAP can be due to a completed hardware single-step only if
1824 - we didn't insert software single-step breakpoints
1825 - the thread to be examined is still the current thread
1826 - this thread is currently being stepped
1828 If any of these events did not occur, we must have stopped due
1829 to hitting a software breakpoint, and have to back up to the
1832 As a special case, we could have hardware single-stepped a
1833 software breakpoint. In this case (prev_pc == breakpoint_pc),
1834 we also need to back up to the breakpoint address. */
1836 if (singlestep_breakpoints_inserted_p
1837 || !ptid_equal (ecs->ptid, inferior_ptid)
1838 || !currently_stepping (ecs->event_thread)
1839 || ecs->event_thread->prev_pc == breakpoint_pc)
1840 regcache_write_pc (regcache, breakpoint_pc);
1845 init_infwait_state (void)
1847 waiton_ptid = pid_to_ptid (-1);
1848 infwait_state = infwait_normal_state;
1852 error_is_running (void)
1855 Cannot execute this command while the selected thread is running."));
1859 ensure_not_running (void)
1861 if (is_running (inferior_ptid))
1862 error_is_running ();
1865 /* Given an execution control state that has been freshly filled in
1866 by an event from the inferior, figure out what it means and take
1867 appropriate action. */
1870 handle_inferior_event (struct execution_control_state *ecs)
1872 int sw_single_step_trap_p = 0;
1873 int stopped_by_watchpoint;
1874 int stepped_after_stopped_by_watchpoint = 0;
1875 struct symtab_and_line stop_pc_sal;
1877 breakpoint_retire_moribund ();
1879 /* Cache the last pid/waitstatus. */
1880 target_last_wait_ptid = ecs->ptid;
1881 target_last_waitstatus = ecs->ws;
1883 /* Always clear state belonging to the previous time we stopped. */
1884 stop_stack_dummy = 0;
1886 adjust_pc_after_break (ecs);
1888 reinit_frame_cache ();
1890 /* If it's a new process, add it to the thread database */
1892 ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
1893 && !ptid_equal (ecs->ptid, minus_one_ptid)
1894 && !in_thread_list (ecs->ptid));
1896 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
1897 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
1898 add_thread (ecs->ptid);
1900 if (ecs->ws.kind != TARGET_WAITKIND_IGNORE)
1902 /* Mark the non-executing threads accordingly. */
1904 || ecs->ws.kind == TARGET_WAITKIND_EXITED
1905 || ecs->ws.kind == TARGET_WAITKIND_SIGNALLED)
1906 set_executing (pid_to_ptid (-1), 0);
1908 set_executing (ecs->ptid, 0);
1911 switch (infwait_state)
1913 case infwait_thread_hop_state:
1915 fprintf_unfiltered (gdb_stdlog, "infrun: infwait_thread_hop_state\n");
1916 /* Cancel the waiton_ptid. */
1917 waiton_ptid = pid_to_ptid (-1);
1920 case infwait_normal_state:
1922 fprintf_unfiltered (gdb_stdlog, "infrun: infwait_normal_state\n");
1925 case infwait_step_watch_state:
1927 fprintf_unfiltered (gdb_stdlog,
1928 "infrun: infwait_step_watch_state\n");
1930 stepped_after_stopped_by_watchpoint = 1;
1933 case infwait_nonstep_watch_state:
1935 fprintf_unfiltered (gdb_stdlog,
1936 "infrun: infwait_nonstep_watch_state\n");
1937 insert_breakpoints ();
1939 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1940 handle things like signals arriving and other things happening
1941 in combination correctly? */
1942 stepped_after_stopped_by_watchpoint = 1;
1946 internal_error (__FILE__, __LINE__, _("bad switch"));
1948 infwait_state = infwait_normal_state;
1950 switch (ecs->ws.kind)
1952 case TARGET_WAITKIND_LOADED:
1954 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
1955 /* Ignore gracefully during startup of the inferior, as it might
1956 be the shell which has just loaded some objects, otherwise
1957 add the symbols for the newly loaded objects. Also ignore at
1958 the beginning of an attach or remote session; we will query
1959 the full list of libraries once the connection is
1961 if (stop_soon == NO_STOP_QUIETLY)
1963 /* Check for any newly added shared libraries if we're
1964 supposed to be adding them automatically. Switch
1965 terminal for any messages produced by
1966 breakpoint_re_set. */
1967 target_terminal_ours_for_output ();
1968 /* NOTE: cagney/2003-11-25: Make certain that the target
1969 stack's section table is kept up-to-date. Architectures,
1970 (e.g., PPC64), use the section table to perform
1971 operations such as address => section name and hence
1972 require the table to contain all sections (including
1973 those found in shared libraries). */
1974 /* NOTE: cagney/2003-11-25: Pass current_target and not
1975 exec_ops to SOLIB_ADD. This is because current GDB is
1976 only tooled to propagate section_table changes out from
1977 the "current_target" (see target_resize_to_sections), and
1978 not up from the exec stratum. This, of course, isn't
1979 right. "infrun.c" should only interact with the
1980 exec/process stratum, instead relying on the target stack
1981 to propagate relevant changes (stop, section table
1982 changed, ...) up to other layers. */
1984 SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
1986 solib_add (NULL, 0, ¤t_target, auto_solib_add);
1988 target_terminal_inferior ();
1990 /* If requested, stop when the dynamic linker notifies
1991 gdb of events. This allows the user to get control
1992 and place breakpoints in initializer routines for
1993 dynamically loaded objects (among other things). */
1994 if (stop_on_solib_events)
1996 stop_stepping (ecs);
2000 /* NOTE drow/2007-05-11: This might be a good place to check
2001 for "catch load". */
2004 /* If we are skipping through a shell, or through shared library
2005 loading that we aren't interested in, resume the program. If
2006 we're running the program normally, also resume. But stop if
2007 we're attaching or setting up a remote connection. */
2008 if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
2010 /* Loading of shared libraries might have changed breakpoint
2011 addresses. Make sure new breakpoints are inserted. */
2012 if (stop_soon == NO_STOP_QUIETLY
2013 && !breakpoints_always_inserted_mode ())
2014 insert_breakpoints ();
2015 resume (0, TARGET_SIGNAL_0);
2016 prepare_to_wait (ecs);
2022 case TARGET_WAITKIND_SPURIOUS:
2024 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
2025 resume (0, TARGET_SIGNAL_0);
2026 prepare_to_wait (ecs);
2029 case TARGET_WAITKIND_EXITED:
2031 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXITED\n");
2032 target_terminal_ours (); /* Must do this before mourn anyway */
2033 print_stop_reason (EXITED, ecs->ws.value.integer);
2035 /* Record the exit code in the convenience variable $_exitcode, so
2036 that the user can inspect this again later. */
2037 set_internalvar (lookup_internalvar ("_exitcode"),
2038 value_from_longest (builtin_type_int,
2039 (LONGEST) ecs->ws.value.integer));
2040 gdb_flush (gdb_stdout);
2041 target_mourn_inferior ();
2042 singlestep_breakpoints_inserted_p = 0;
2043 stop_print_frame = 0;
2044 stop_stepping (ecs);
2047 case TARGET_WAITKIND_SIGNALLED:
2049 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SIGNALLED\n");
2050 stop_print_frame = 0;
2051 target_terminal_ours (); /* Must do this before mourn anyway */
2053 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
2054 reach here unless the inferior is dead. However, for years
2055 target_kill() was called here, which hints that fatal signals aren't
2056 really fatal on some systems. If that's true, then some changes
2058 target_mourn_inferior ();
2060 print_stop_reason (SIGNAL_EXITED, ecs->ws.value.sig);
2061 singlestep_breakpoints_inserted_p = 0;
2062 stop_stepping (ecs);
2065 /* The following are the only cases in which we keep going;
2066 the above cases end in a continue or goto. */
2067 case TARGET_WAITKIND_FORKED:
2068 case TARGET_WAITKIND_VFORKED:
2070 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
2071 pending_follow.kind = ecs->ws.kind;
2073 pending_follow.fork_event.parent_pid = ecs->ptid;
2074 pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
2076 if (!ptid_equal (ecs->ptid, inferior_ptid))
2078 context_switch (ecs->ptid);
2079 reinit_frame_cache ();
2082 stop_pc = read_pc ();
2084 ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
2086 ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
2088 /* If no catchpoint triggered for this, then keep going. */
2089 if (ecs->random_signal)
2091 ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
2095 ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
2096 goto process_event_stop_test;
2098 case TARGET_WAITKIND_EXECD:
2100 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
2101 pending_follow.execd_pathname =
2102 savestring (ecs->ws.value.execd_pathname,
2103 strlen (ecs->ws.value.execd_pathname));
2105 /* This causes the eventpoints and symbol table to be reset. Must
2106 do this now, before trying to determine whether to stop. */
2107 follow_exec (inferior_ptid, pending_follow.execd_pathname);
2108 xfree (pending_follow.execd_pathname);
2110 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
2113 /* The breakpoints module may need to touch the inferior's
2114 memory. Switch to the (stopped) event ptid
2116 ptid_t saved_inferior_ptid = inferior_ptid;
2117 inferior_ptid = ecs->ptid;
2119 ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
2121 ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
2122 inferior_ptid = saved_inferior_ptid;
2125 if (!ptid_equal (ecs->ptid, inferior_ptid))
2127 context_switch (ecs->ptid);
2128 reinit_frame_cache ();
2131 /* If no catchpoint triggered for this, then keep going. */
2132 if (ecs->random_signal)
2134 ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
2138 ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
2139 goto process_event_stop_test;
2141 /* Be careful not to try to gather much state about a thread
2142 that's in a syscall. It's frequently a losing proposition. */
2143 case TARGET_WAITKIND_SYSCALL_ENTRY:
2145 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
2146 resume (0, TARGET_SIGNAL_0);
2147 prepare_to_wait (ecs);
2150 /* Before examining the threads further, step this thread to
2151 get it entirely out of the syscall. (We get notice of the
2152 event when the thread is just on the verge of exiting a
2153 syscall. Stepping one instruction seems to get it back
2155 case TARGET_WAITKIND_SYSCALL_RETURN:
2157 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
2158 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
2159 prepare_to_wait (ecs);
2162 case TARGET_WAITKIND_STOPPED:
2164 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
2165 ecs->event_thread->stop_signal = ecs->ws.value.sig;
2168 /* We had an event in the inferior, but we are not interested
2169 in handling it at this level. The lower layers have already
2170 done what needs to be done, if anything.
2172 One of the possible circumstances for this is when the
2173 inferior produces output for the console. The inferior has
2174 not stopped, and we are ignoring the event. Another possible
2175 circumstance is any event which the lower level knows will be
2176 reported multiple times without an intervening resume. */
2177 case TARGET_WAITKIND_IGNORE:
2179 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
2180 prepare_to_wait (ecs);
2184 if (ecs->new_thread_event)
2187 /* Non-stop assumes that the target handles adding new threads
2188 to the thread list. */
2189 internal_error (__FILE__, __LINE__, "\
2190 targets should add new threads to the thread list themselves in non-stop mode.");
2192 /* We may want to consider not doing a resume here in order to
2193 give the user a chance to play with the new thread. It might
2194 be good to make that a user-settable option. */
2196 /* At this point, all threads are stopped (happens automatically
2197 in either the OS or the native code). Therefore we need to
2198 continue all threads in order to make progress. */
2200 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
2201 prepare_to_wait (ecs);
2205 /* Do we need to clean up the state of a thread that has completed a
2206 displaced single-step? (Doing so usually affects the PC, so do
2207 it here, before we set stop_pc.) */
2208 if (ecs->ws.kind == TARGET_WAITKIND_STOPPED)
2209 displaced_step_fixup (ecs->ptid, ecs->event_thread->stop_signal);
2211 stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
2215 fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = 0x%s\n",
2216 paddr_nz (stop_pc));
2217 if (STOPPED_BY_WATCHPOINT (&ecs->ws))
2220 fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
2222 if (target_stopped_data_address (¤t_target, &addr))
2223 fprintf_unfiltered (gdb_stdlog,
2224 "infrun: stopped data address = 0x%s\n",
2227 fprintf_unfiltered (gdb_stdlog,
2228 "infrun: (no data address available)\n");
2232 if (stepping_past_singlestep_breakpoint)
2234 gdb_assert (singlestep_breakpoints_inserted_p);
2235 gdb_assert (ptid_equal (singlestep_ptid, ecs->ptid));
2236 gdb_assert (!ptid_equal (singlestep_ptid, saved_singlestep_ptid));
2238 stepping_past_singlestep_breakpoint = 0;
2240 /* We've either finished single-stepping past the single-step
2241 breakpoint, or stopped for some other reason. It would be nice if
2242 we could tell, but we can't reliably. */
2243 if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
2246 fprintf_unfiltered (gdb_stdlog, "infrun: stepping_past_singlestep_breakpoint\n");
2247 /* Pull the single step breakpoints out of the target. */
2248 remove_single_step_breakpoints ();
2249 singlestep_breakpoints_inserted_p = 0;
2251 ecs->random_signal = 0;
2253 context_switch (saved_singlestep_ptid);
2254 if (deprecated_context_hook)
2255 deprecated_context_hook (pid_to_thread_id (ecs->ptid));
2257 resume (1, TARGET_SIGNAL_0);
2258 prepare_to_wait (ecs);
2263 stepping_past_singlestep_breakpoint = 0;
2265 if (!ptid_equal (deferred_step_ptid, null_ptid))
2267 /* In non-stop mode, there's never a deferred_step_ptid set. */
2268 gdb_assert (!non_stop);
2270 /* If we stopped for some other reason than single-stepping, ignore
2271 the fact that we were supposed to switch back. */
2272 if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
2274 struct thread_info *tp;
2277 fprintf_unfiltered (gdb_stdlog,
2278 "infrun: handling deferred step\n");
2280 /* Pull the single step breakpoints out of the target. */
2281 if (singlestep_breakpoints_inserted_p)
2283 remove_single_step_breakpoints ();
2284 singlestep_breakpoints_inserted_p = 0;
2287 /* Note: We do not call context_switch at this point, as the
2288 context is already set up for stepping the original thread. */
2289 switch_to_thread (deferred_step_ptid);
2290 deferred_step_ptid = null_ptid;
2291 /* Suppress spurious "Switching to ..." message. */
2292 previous_inferior_ptid = inferior_ptid;
2294 resume (1, TARGET_SIGNAL_0);
2295 prepare_to_wait (ecs);
2299 deferred_step_ptid = null_ptid;
2302 /* See if a thread hit a thread-specific breakpoint that was meant for
2303 another thread. If so, then step that thread past the breakpoint,
2306 if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
2308 int thread_hop_needed = 0;
2310 /* Check if a regular breakpoint has been hit before checking
2311 for a potential single step breakpoint. Otherwise, GDB will
2312 not see this breakpoint hit when stepping onto breakpoints. */
2313 if (regular_breakpoint_inserted_here_p (stop_pc))
2315 ecs->random_signal = 0;
2316 if (!breakpoint_thread_match (stop_pc, ecs->ptid))
2317 thread_hop_needed = 1;
2319 else if (singlestep_breakpoints_inserted_p)
2321 /* We have not context switched yet, so this should be true
2322 no matter which thread hit the singlestep breakpoint. */
2323 gdb_assert (ptid_equal (inferior_ptid, singlestep_ptid));
2325 fprintf_unfiltered (gdb_stdlog, "infrun: software single step "
2327 target_pid_to_str (ecs->ptid));
2329 ecs->random_signal = 0;
2330 /* The call to in_thread_list is necessary because PTIDs sometimes
2331 change when we go from single-threaded to multi-threaded. If
2332 the singlestep_ptid is still in the list, assume that it is
2333 really different from ecs->ptid. */
2334 if (!ptid_equal (singlestep_ptid, ecs->ptid)
2335 && in_thread_list (singlestep_ptid))
2337 /* If the PC of the thread we were trying to single-step
2338 has changed, discard this event (which we were going
2339 to ignore anyway), and pretend we saw that thread
2340 trap. This prevents us continuously moving the
2341 single-step breakpoint forward, one instruction at a
2342 time. If the PC has changed, then the thread we were
2343 trying to single-step has trapped or been signalled,
2344 but the event has not been reported to GDB yet.
2346 There might be some cases where this loses signal
2347 information, if a signal has arrived at exactly the
2348 same time that the PC changed, but this is the best
2349 we can do with the information available. Perhaps we
2350 should arrange to report all events for all threads
2351 when they stop, or to re-poll the remote looking for
2352 this particular thread (i.e. temporarily enable
2355 CORE_ADDR new_singlestep_pc
2356 = regcache_read_pc (get_thread_regcache (singlestep_ptid));
2358 if (new_singlestep_pc != singlestep_pc)
2360 enum target_signal stop_signal;
2363 fprintf_unfiltered (gdb_stdlog, "infrun: unexpected thread,"
2364 " but expected thread advanced also\n");
2366 /* The current context still belongs to
2367 singlestep_ptid. Don't swap here, since that's
2368 the context we want to use. Just fudge our
2369 state and continue. */
2370 stop_signal = ecs->event_thread->stop_signal;
2371 ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
2372 ecs->ptid = singlestep_ptid;
2373 ecs->event_thread = find_thread_pid (ecs->ptid);
2374 ecs->event_thread->stop_signal = stop_signal;
2375 stop_pc = new_singlestep_pc;
2380 fprintf_unfiltered (gdb_stdlog,
2381 "infrun: unexpected thread\n");
2383 thread_hop_needed = 1;
2384 stepping_past_singlestep_breakpoint = 1;
2385 saved_singlestep_ptid = singlestep_ptid;
2390 if (thread_hop_needed)
2392 int remove_status = 0;
2395 fprintf_unfiltered (gdb_stdlog, "infrun: thread_hop_needed\n");
2397 /* Saw a breakpoint, but it was hit by the wrong thread.
2400 if (singlestep_breakpoints_inserted_p)
2402 /* Pull the single step breakpoints out of the target. */
2403 remove_single_step_breakpoints ();
2404 singlestep_breakpoints_inserted_p = 0;
2407 /* If the arch can displace step, don't remove the
2409 if (!use_displaced_stepping (current_gdbarch))
2410 remove_status = remove_breakpoints ();
2412 /* Did we fail to remove breakpoints? If so, try
2413 to set the PC past the bp. (There's at least
2414 one situation in which we can fail to remove
2415 the bp's: On HP-UX's that use ttrace, we can't
2416 change the address space of a vforking child
2417 process until the child exits (well, okay, not
2418 then either :-) or execs. */
2419 if (remove_status != 0)
2420 error (_("Cannot step over breakpoint hit in wrong thread"));
2423 if (!ptid_equal (inferior_ptid, ecs->ptid))
2424 context_switch (ecs->ptid);
2428 /* Only need to require the next event from this
2429 thread in all-stop mode. */
2430 waiton_ptid = ecs->ptid;
2431 infwait_state = infwait_thread_hop_state;
2434 ecs->event_thread->stepping_over_breakpoint = 1;
2436 registers_changed ();
2440 else if (singlestep_breakpoints_inserted_p)
2442 sw_single_step_trap_p = 1;
2443 ecs->random_signal = 0;
2447 ecs->random_signal = 1;
2449 /* See if something interesting happened to the non-current thread. If
2450 so, then switch to that thread. */
2451 if (!ptid_equal (ecs->ptid, inferior_ptid))
2454 fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
2456 context_switch (ecs->ptid);
2458 if (deprecated_context_hook)
2459 deprecated_context_hook (pid_to_thread_id (ecs->ptid));
2462 if (singlestep_breakpoints_inserted_p)
2464 /* Pull the single step breakpoints out of the target. */
2465 remove_single_step_breakpoints ();
2466 singlestep_breakpoints_inserted_p = 0;
2469 if (stepped_after_stopped_by_watchpoint)
2470 stopped_by_watchpoint = 0;
2472 stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
2474 /* If necessary, step over this watchpoint. We'll be back to display
2476 if (stopped_by_watchpoint
2477 && (HAVE_STEPPABLE_WATCHPOINT
2478 || gdbarch_have_nonsteppable_watchpoint (current_gdbarch)))
2480 /* At this point, we are stopped at an instruction which has
2481 attempted to write to a piece of memory under control of
2482 a watchpoint. The instruction hasn't actually executed
2483 yet. If we were to evaluate the watchpoint expression
2484 now, we would get the old value, and therefore no change
2485 would seem to have occurred.
2487 In order to make watchpoints work `right', we really need
2488 to complete the memory write, and then evaluate the
2489 watchpoint expression. We do this by single-stepping the
2492 It may not be necessary to disable the watchpoint to stop over
2493 it. For example, the PA can (with some kernel cooperation)
2494 single step over a watchpoint without disabling the watchpoint.
2496 It is far more common to need to disable a watchpoint to step
2497 the inferior over it. If we have non-steppable watchpoints,
2498 we must disable the current watchpoint; it's simplest to
2499 disable all watchpoints and breakpoints. */
2501 if (!HAVE_STEPPABLE_WATCHPOINT)
2502 remove_breakpoints ();
2503 registers_changed ();
2504 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */
2505 waiton_ptid = ecs->ptid;
2506 if (HAVE_STEPPABLE_WATCHPOINT)
2507 infwait_state = infwait_step_watch_state;
2509 infwait_state = infwait_nonstep_watch_state;
2510 prepare_to_wait (ecs);
2514 ecs->stop_func_start = 0;
2515 ecs->stop_func_end = 0;
2516 ecs->stop_func_name = 0;
2517 /* Don't care about return value; stop_func_start and stop_func_name
2518 will both be 0 if it doesn't work. */
2519 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
2520 &ecs->stop_func_start, &ecs->stop_func_end);
2521 ecs->stop_func_start
2522 += gdbarch_deprecated_function_start_offset (current_gdbarch);
2523 ecs->event_thread->stepping_over_breakpoint = 0;
2524 bpstat_clear (&ecs->event_thread->stop_bpstat);
2526 stop_print_frame = 1;
2527 ecs->random_signal = 0;
2528 stopped_by_random_signal = 0;
2530 if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
2531 && ecs->event_thread->trap_expected
2532 && gdbarch_single_step_through_delay_p (current_gdbarch)
2533 && currently_stepping (ecs->event_thread))
2535 /* We're trying to step off a breakpoint. Turns out that we're
2536 also on an instruction that needs to be stepped multiple
2537 times before it's been fully executing. E.g., architectures
2538 with a delay slot. It needs to be stepped twice, once for
2539 the instruction and once for the delay slot. */
2540 int step_through_delay
2541 = gdbarch_single_step_through_delay (current_gdbarch,
2542 get_current_frame ());
2543 if (debug_infrun && step_through_delay)
2544 fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
2545 if (ecs->event_thread->step_range_end == 0 && step_through_delay)
2547 /* The user issued a continue when stopped at a breakpoint.
2548 Set up for another trap and get out of here. */
2549 ecs->event_thread->stepping_over_breakpoint = 1;
2553 else if (step_through_delay)
2555 /* The user issued a step when stopped at a breakpoint.
2556 Maybe we should stop, maybe we should not - the delay
2557 slot *might* correspond to a line of source. In any
2558 case, don't decide that here, just set
2559 ecs->stepping_over_breakpoint, making sure we
2560 single-step again before breakpoints are re-inserted. */
2561 ecs->event_thread->stepping_over_breakpoint = 1;
2565 /* Look at the cause of the stop, and decide what to do.
2566 The alternatives are:
2567 1) stop_stepping and return; to really stop and return to the debugger,
2568 2) keep_going and return to start up again
2569 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
2570 3) set ecs->random_signal to 1, and the decision between 1 and 2
2571 will be made according to the signal handling tables. */
2573 /* First, distinguish signals caused by the debugger from signals
2574 that have to do with the program's own actions. Note that
2575 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
2576 on the operating system version. Here we detect when a SIGILL or
2577 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
2578 something similar for SIGSEGV, since a SIGSEGV will be generated
2579 when we're trying to execute a breakpoint instruction on a
2580 non-executable stack. This happens for call dummy breakpoints
2581 for architectures like SPARC that place call dummies on the
2584 If we're doing a displaced step past a breakpoint, then the
2585 breakpoint is always inserted at the original instruction;
2586 non-standard signals can't be explained by the breakpoint. */
2587 if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
2588 || (! ecs->event_thread->trap_expected
2589 && breakpoint_inserted_here_p (stop_pc)
2590 && (ecs->event_thread->stop_signal == TARGET_SIGNAL_ILL
2591 || ecs->event_thread->stop_signal == TARGET_SIGNAL_SEGV
2592 || ecs->event_thread->stop_signal == TARGET_SIGNAL_EMT))
2593 || stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_NO_SIGSTOP
2594 || stop_soon == STOP_QUIETLY_REMOTE)
2596 if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
2599 fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
2600 stop_print_frame = 0;
2601 stop_stepping (ecs);
2605 /* This is originated from start_remote(), start_inferior() and
2606 shared libraries hook functions. */
2607 if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
2610 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
2611 stop_stepping (ecs);
2615 /* This originates from attach_command(). We need to overwrite
2616 the stop_signal here, because some kernels don't ignore a
2617 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
2618 See more comments in inferior.h. On the other hand, if we
2619 get a non-SIGSTOP, report it to the user - assume the backend
2620 will handle the SIGSTOP if it should show up later.
2622 Also consider that the attach is complete when we see a
2623 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
2624 target extended-remote report it instead of a SIGSTOP
2625 (e.g. gdbserver). We already rely on SIGTRAP being our
2626 signal, so this is no exception. */
2627 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
2628 && (ecs->event_thread->stop_signal == TARGET_SIGNAL_STOP
2629 || ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP))
2631 stop_stepping (ecs);
2632 ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
2636 /* See if there is a breakpoint at the current PC. */
2637 ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
2639 /* Following in case break condition called a
2641 stop_print_frame = 1;
2643 /* NOTE: cagney/2003-03-29: These two checks for a random signal
2644 at one stage in the past included checks for an inferior
2645 function call's call dummy's return breakpoint. The original
2646 comment, that went with the test, read:
2648 ``End of a stack dummy. Some systems (e.g. Sony news) give
2649 another signal besides SIGTRAP, so check here as well as
2652 If someone ever tries to get get call dummys on a
2653 non-executable stack to work (where the target would stop
2654 with something like a SIGSEGV), then those tests might need
2655 to be re-instated. Given, however, that the tests were only
2656 enabled when momentary breakpoints were not being used, I
2657 suspect that it won't be the case.
2659 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
2660 be necessary for call dummies on a non-executable stack on
2663 if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
2665 = !(bpstat_explains_signal (ecs->event_thread->stop_bpstat)
2666 || ecs->event_thread->trap_expected
2667 || (ecs->event_thread->step_range_end
2668 && ecs->event_thread->step_resume_breakpoint == NULL));
2671 ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
2672 if (!ecs->random_signal)
2673 ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
2677 /* When we reach this point, we've pretty much decided
2678 that the reason for stopping must've been a random
2679 (unexpected) signal. */
2682 ecs->random_signal = 1;
2684 process_event_stop_test:
2685 /* For the program's own signals, act according to
2686 the signal handling tables. */
2688 if (ecs->random_signal)
2690 /* Signal not for debugging purposes. */
2694 fprintf_unfiltered (gdb_stdlog, "infrun: random signal %d\n",
2695 ecs->event_thread->stop_signal);
2697 stopped_by_random_signal = 1;
2699 if (signal_print[ecs->event_thread->stop_signal])
2702 target_terminal_ours_for_output ();
2703 print_stop_reason (SIGNAL_RECEIVED, ecs->event_thread->stop_signal);
2705 if (signal_stop_state (ecs->event_thread->stop_signal))
2707 stop_stepping (ecs);
2710 /* If not going to stop, give terminal back
2711 if we took it away. */
2713 target_terminal_inferior ();
2715 /* Clear the signal if it should not be passed. */
2716 if (signal_program[ecs->event_thread->stop_signal] == 0)
2717 ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
2719 if (ecs->event_thread->prev_pc == read_pc ()
2720 && ecs->event_thread->trap_expected
2721 && ecs->event_thread->step_resume_breakpoint == NULL)
2723 /* We were just starting a new sequence, attempting to
2724 single-step off of a breakpoint and expecting a SIGTRAP.
2725 Instead this signal arrives. This signal will take us out
2726 of the stepping range so GDB needs to remember to, when
2727 the signal handler returns, resume stepping off that
2729 /* To simplify things, "continue" is forced to use the same
2730 code paths as single-step - set a breakpoint at the
2731 signal return address and then, once hit, step off that
2734 fprintf_unfiltered (gdb_stdlog,
2735 "infrun: signal arrived while stepping over "
2738 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2739 ecs->event_thread->step_after_step_resume_breakpoint = 1;
2744 if (ecs->event_thread->step_range_end != 0
2745 && ecs->event_thread->stop_signal != TARGET_SIGNAL_0
2746 && (ecs->event_thread->step_range_start <= stop_pc
2747 && stop_pc < ecs->event_thread->step_range_end)
2748 && frame_id_eq (get_frame_id (get_current_frame ()),
2749 ecs->event_thread->step_frame_id)
2750 && ecs->event_thread->step_resume_breakpoint == NULL)
2752 /* The inferior is about to take a signal that will take it
2753 out of the single step range. Set a breakpoint at the
2754 current PC (which is presumably where the signal handler
2755 will eventually return) and then allow the inferior to
2758 Note that this is only needed for a signal delivered
2759 while in the single-step range. Nested signals aren't a
2760 problem as they eventually all return. */
2762 fprintf_unfiltered (gdb_stdlog,
2763 "infrun: signal may take us out of "
2764 "single-step range\n");
2766 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2771 /* Note: step_resume_breakpoint may be non-NULL. This occures
2772 when either there's a nested signal, or when there's a
2773 pending signal enabled just as the signal handler returns
2774 (leaving the inferior at the step-resume-breakpoint without
2775 actually executing it). Either way continue until the
2776 breakpoint is really hit. */
2781 /* Handle cases caused by hitting a breakpoint. */
2783 CORE_ADDR jmp_buf_pc;
2784 struct bpstat_what what;
2786 what = bpstat_what (ecs->event_thread->stop_bpstat);
2788 if (what.call_dummy)
2790 stop_stack_dummy = 1;
2793 switch (what.main_action)
2795 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
2796 /* If we hit the breakpoint at longjmp while stepping, we
2797 install a momentary breakpoint at the target of the
2801 fprintf_unfiltered (gdb_stdlog,
2802 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
2804 ecs->event_thread->stepping_over_breakpoint = 1;
2806 if (!gdbarch_get_longjmp_target_p (current_gdbarch)
2807 || !gdbarch_get_longjmp_target (current_gdbarch,
2808 get_current_frame (), &jmp_buf_pc))
2811 fprintf_unfiltered (gdb_stdlog, "\
2812 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
2817 /* We're going to replace the current step-resume breakpoint
2818 with a longjmp-resume breakpoint. */
2819 delete_step_resume_breakpoint (ecs->event_thread);
2821 /* Insert a breakpoint at resume address. */
2822 insert_longjmp_resume_breakpoint (jmp_buf_pc);
2827 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
2829 fprintf_unfiltered (gdb_stdlog,
2830 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
2832 gdb_assert (ecs->event_thread->step_resume_breakpoint != NULL);
2833 delete_step_resume_breakpoint (ecs->event_thread);
2836 print_stop_reason (END_STEPPING_RANGE, 0);
2837 stop_stepping (ecs);
2840 case BPSTAT_WHAT_SINGLE:
2842 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
2843 ecs->event_thread->stepping_over_breakpoint = 1;
2844 /* Still need to check other stuff, at least the case
2845 where we are stepping and step out of the right range. */
2848 case BPSTAT_WHAT_STOP_NOISY:
2850 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
2851 stop_print_frame = 1;
2853 /* We are about to nuke the step_resume_breakpointt via the
2854 cleanup chain, so no need to worry about it here. */
2856 stop_stepping (ecs);
2859 case BPSTAT_WHAT_STOP_SILENT:
2861 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
2862 stop_print_frame = 0;
2864 /* We are about to nuke the step_resume_breakpoin via the
2865 cleanup chain, so no need to worry about it here. */
2867 stop_stepping (ecs);
2870 case BPSTAT_WHAT_STEP_RESUME:
2872 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
2874 delete_step_resume_breakpoint (ecs->event_thread);
2875 if (ecs->event_thread->step_after_step_resume_breakpoint)
2877 /* Back when the step-resume breakpoint was inserted, we
2878 were trying to single-step off a breakpoint. Go back
2880 ecs->event_thread->step_after_step_resume_breakpoint = 0;
2881 ecs->event_thread->stepping_over_breakpoint = 1;
2887 case BPSTAT_WHAT_CHECK_SHLIBS:
2888 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
2891 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
2893 /* Check for any newly added shared libraries if we're
2894 supposed to be adding them automatically. Switch
2895 terminal for any messages produced by
2896 breakpoint_re_set. */
2897 target_terminal_ours_for_output ();
2898 /* NOTE: cagney/2003-11-25: Make certain that the target
2899 stack's section table is kept up-to-date. Architectures,
2900 (e.g., PPC64), use the section table to perform
2901 operations such as address => section name and hence
2902 require the table to contain all sections (including
2903 those found in shared libraries). */
2904 /* NOTE: cagney/2003-11-25: Pass current_target and not
2905 exec_ops to SOLIB_ADD. This is because current GDB is
2906 only tooled to propagate section_table changes out from
2907 the "current_target" (see target_resize_to_sections), and
2908 not up from the exec stratum. This, of course, isn't
2909 right. "infrun.c" should only interact with the
2910 exec/process stratum, instead relying on the target stack
2911 to propagate relevant changes (stop, section table
2912 changed, ...) up to other layers. */
2914 SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
2916 solib_add (NULL, 0, ¤t_target, auto_solib_add);
2918 target_terminal_inferior ();
2920 /* If requested, stop when the dynamic linker notifies
2921 gdb of events. This allows the user to get control
2922 and place breakpoints in initializer routines for
2923 dynamically loaded objects (among other things). */
2924 if (stop_on_solib_events || stop_stack_dummy)
2926 stop_stepping (ecs);
2930 /* If we stopped due to an explicit catchpoint, then the
2931 (see above) call to SOLIB_ADD pulled in any symbols
2932 from a newly-loaded library, if appropriate.
2934 We do want the inferior to stop, but not where it is
2935 now, which is in the dynamic linker callback. Rather,
2936 we would like it stop in the user's program, just after
2937 the call that caused this catchpoint to trigger. That
2938 gives the user a more useful vantage from which to
2939 examine their program's state. */
2940 else if (what.main_action
2941 == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
2943 /* ??rehrauer: If I could figure out how to get the
2944 right return PC from here, we could just set a temp
2945 breakpoint and resume. I'm not sure we can without
2946 cracking open the dld's shared libraries and sniffing
2947 their unwind tables and text/data ranges, and that's
2948 not a terribly portable notion.
2950 Until that time, we must step the inferior out of the
2951 dld callback, and also out of the dld itself (and any
2952 code or stubs in libdld.sl, such as "shl_load" and
2953 friends) until we reach non-dld code. At that point,
2954 we can stop stepping. */
2955 bpstat_get_triggered_catchpoints (ecs->event_thread->stop_bpstat,
2958 stepping_through_solib_catchpoints);
2959 ecs->event_thread->stepping_through_solib_after_catch = 1;
2961 /* Be sure to lift all breakpoints, so the inferior does
2962 actually step past this point... */
2963 ecs->event_thread->stepping_over_breakpoint = 1;
2968 /* We want to step over this breakpoint, then keep going. */
2969 ecs->event_thread->stepping_over_breakpoint = 1;
2975 case BPSTAT_WHAT_LAST:
2976 /* Not a real code, but listed here to shut up gcc -Wall. */
2978 case BPSTAT_WHAT_KEEP_CHECKING:
2983 /* We come here if we hit a breakpoint but should not
2984 stop for it. Possibly we also were stepping
2985 and should stop for that. So fall through and
2986 test for stepping. But, if not stepping,
2989 /* Are we stepping to get the inferior out of the dynamic linker's
2990 hook (and possibly the dld itself) after catching a shlib
2992 if (ecs->event_thread->stepping_through_solib_after_catch)
2994 #if defined(SOLIB_ADD)
2995 /* Have we reached our destination? If not, keep going. */
2996 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc))
2999 fprintf_unfiltered (gdb_stdlog, "infrun: stepping in dynamic linker\n");
3000 ecs->event_thread->stepping_over_breakpoint = 1;
3006 fprintf_unfiltered (gdb_stdlog, "infrun: step past dynamic linker\n");
3007 /* Else, stop and report the catchpoint(s) whose triggering
3008 caused us to begin stepping. */
3009 ecs->event_thread->stepping_through_solib_after_catch = 0;
3010 bpstat_clear (&ecs->event_thread->stop_bpstat);
3011 ecs->event_thread->stop_bpstat
3012 = bpstat_copy (ecs->event_thread->stepping_through_solib_catchpoints);
3013 bpstat_clear (&ecs->event_thread->stepping_through_solib_catchpoints);
3014 stop_print_frame = 1;
3015 stop_stepping (ecs);
3019 if (ecs->event_thread->step_resume_breakpoint)
3022 fprintf_unfiltered (gdb_stdlog,
3023 "infrun: step-resume breakpoint is inserted\n");
3025 /* Having a step-resume breakpoint overrides anything
3026 else having to do with stepping commands until
3027 that breakpoint is reached. */
3032 if (ecs->event_thread->step_range_end == 0)
3035 fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
3036 /* Likewise if we aren't even stepping. */
3041 /* If stepping through a line, keep going if still within it.
3043 Note that step_range_end is the address of the first instruction
3044 beyond the step range, and NOT the address of the last instruction
3046 if (stop_pc >= ecs->event_thread->step_range_start
3047 && stop_pc < ecs->event_thread->step_range_end)
3050 fprintf_unfiltered (gdb_stdlog, "infrun: stepping inside range [0x%s-0x%s]\n",
3051 paddr_nz (ecs->event_thread->step_range_start),
3052 paddr_nz (ecs->event_thread->step_range_end));
3057 /* We stepped out of the stepping range. */
3059 /* If we are stepping at the source level and entered the runtime
3060 loader dynamic symbol resolution code, we keep on single stepping
3061 until we exit the run time loader code and reach the callee's
3063 if (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
3064 && in_solib_dynsym_resolve_code (stop_pc))
3066 CORE_ADDR pc_after_resolver =
3067 gdbarch_skip_solib_resolver (current_gdbarch, stop_pc);
3070 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into dynsym resolve code\n");
3072 if (pc_after_resolver)
3074 /* Set up a step-resume breakpoint at the address
3075 indicated by SKIP_SOLIB_RESOLVER. */
3076 struct symtab_and_line sr_sal;
3078 sr_sal.pc = pc_after_resolver;
3080 insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
3087 if (ecs->event_thread->step_range_end != 1
3088 && (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
3089 || ecs->event_thread->step_over_calls == STEP_OVER_ALL)
3090 && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME)
3093 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into signal trampoline\n");
3094 /* The inferior, while doing a "step" or "next", has ended up in
3095 a signal trampoline (either by a signal being delivered or by
3096 the signal handler returning). Just single-step until the
3097 inferior leaves the trampoline (either by calling the handler
3103 /* Check for subroutine calls. The check for the current frame
3104 equalling the step ID is not necessary - the check of the
3105 previous frame's ID is sufficient - but it is a common case and
3106 cheaper than checking the previous frame's ID.
3108 NOTE: frame_id_eq will never report two invalid frame IDs as
3109 being equal, so to get into this block, both the current and
3110 previous frame must have valid frame IDs. */
3111 if (!frame_id_eq (get_frame_id (get_current_frame ()),
3112 ecs->event_thread->step_frame_id)
3113 && frame_id_eq (frame_unwind_id (get_current_frame ()),
3114 ecs->event_thread->step_frame_id))
3116 CORE_ADDR real_stop_pc;
3119 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
3121 if ((ecs->event_thread->step_over_calls == STEP_OVER_NONE)
3122 || ((ecs->event_thread->step_range_end == 1)
3123 && in_prologue (ecs->event_thread->prev_pc,
3124 ecs->stop_func_start)))
3126 /* I presume that step_over_calls is only 0 when we're
3127 supposed to be stepping at the assembly language level
3128 ("stepi"). Just stop. */
3129 /* Also, maybe we just did a "nexti" inside a prolog, so we
3130 thought it was a subroutine call but it was not. Stop as
3133 print_stop_reason (END_STEPPING_RANGE, 0);
3134 stop_stepping (ecs);
3138 if (ecs->event_thread->step_over_calls == STEP_OVER_ALL)
3140 /* We're doing a "next", set a breakpoint at callee's return
3141 address (the address at which the caller will
3143 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3148 /* If we are in a function call trampoline (a stub between the
3149 calling routine and the real function), locate the real
3150 function. That's what tells us (a) whether we want to step
3151 into it at all, and (b) what prologue we want to run to the
3152 end of, if we do step into it. */
3153 real_stop_pc = skip_language_trampoline (get_current_frame (), stop_pc);
3154 if (real_stop_pc == 0)
3155 real_stop_pc = gdbarch_skip_trampoline_code
3156 (current_gdbarch, get_current_frame (), stop_pc);
3157 if (real_stop_pc != 0)
3158 ecs->stop_func_start = real_stop_pc;
3160 if (in_solib_dynsym_resolve_code (ecs->stop_func_start))
3162 struct symtab_and_line sr_sal;
3164 sr_sal.pc = ecs->stop_func_start;
3166 insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
3171 /* If we have line number information for the function we are
3172 thinking of stepping into, step into it.
3174 If there are several symtabs at that PC (e.g. with include
3175 files), just want to know whether *any* of them have line
3176 numbers. find_pc_line handles this. */
3178 struct symtab_and_line tmp_sal;
3180 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
3181 if (tmp_sal.line != 0)
3183 step_into_function (ecs);
3188 /* If we have no line number and the step-stop-if-no-debug is
3189 set, we stop the step so that the user has a chance to switch
3190 in assembly mode. */
3191 if (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
3192 && step_stop_if_no_debug)
3195 print_stop_reason (END_STEPPING_RANGE, 0);
3196 stop_stepping (ecs);
3200 /* Set a breakpoint at callee's return address (the address at
3201 which the caller will resume). */
3202 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3207 /* If we're in the return path from a shared library trampoline,
3208 we want to proceed through the trampoline when stepping. */
3209 if (gdbarch_in_solib_return_trampoline (current_gdbarch,
3210 stop_pc, ecs->stop_func_name))
3212 /* Determine where this trampoline returns. */
3213 CORE_ADDR real_stop_pc;
3214 real_stop_pc = gdbarch_skip_trampoline_code
3215 (current_gdbarch, get_current_frame (), stop_pc);
3218 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into solib return tramp\n");
3220 /* Only proceed through if we know where it's going. */
3223 /* And put the step-breakpoint there and go until there. */
3224 struct symtab_and_line sr_sal;
3226 init_sal (&sr_sal); /* initialize to zeroes */
3227 sr_sal.pc = real_stop_pc;
3228 sr_sal.section = find_pc_overlay (sr_sal.pc);
3230 /* Do not specify what the fp should be when we stop since
3231 on some machines the prologue is where the new fp value
3233 insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
3235 /* Restart without fiddling with the step ranges or
3242 stop_pc_sal = find_pc_line (stop_pc, 0);
3244 /* NOTE: tausq/2004-05-24: This if block used to be done before all
3245 the trampoline processing logic, however, there are some trampolines
3246 that have no names, so we should do trampoline handling first. */
3247 if (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
3248 && ecs->stop_func_name == NULL
3249 && stop_pc_sal.line == 0)
3252 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into undebuggable function\n");
3254 /* The inferior just stepped into, or returned to, an
3255 undebuggable function (where there is no debugging information
3256 and no line number corresponding to the address where the
3257 inferior stopped). Since we want to skip this kind of code,
3258 we keep going until the inferior returns from this
3259 function - unless the user has asked us not to (via
3260 set step-mode) or we no longer know how to get back
3261 to the call site. */
3262 if (step_stop_if_no_debug
3263 || !frame_id_p (frame_unwind_id (get_current_frame ())))
3265 /* If we have no line number and the step-stop-if-no-debug
3266 is set, we stop the step so that the user has a chance to
3267 switch in assembly mode. */
3269 print_stop_reason (END_STEPPING_RANGE, 0);
3270 stop_stepping (ecs);
3275 /* Set a breakpoint at callee's return address (the address
3276 at which the caller will resume). */
3277 insert_step_resume_breakpoint_at_caller (get_current_frame ());
3283 if (ecs->event_thread->step_range_end == 1)
3285 /* It is stepi or nexti. We always want to stop stepping after
3288 fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
3290 print_stop_reason (END_STEPPING_RANGE, 0);
3291 stop_stepping (ecs);
3295 if (stop_pc_sal.line == 0)
3297 /* We have no line number information. That means to stop
3298 stepping (does this always happen right after one instruction,
3299 when we do "s" in a function with no line numbers,
3300 or can this happen as a result of a return or longjmp?). */
3302 fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
3304 print_stop_reason (END_STEPPING_RANGE, 0);
3305 stop_stepping (ecs);
3309 if ((stop_pc == stop_pc_sal.pc)
3310 && (ecs->event_thread->current_line != stop_pc_sal.line
3311 || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
3313 /* We are at the start of a different line. So stop. Note that
3314 we don't stop if we step into the middle of a different line.
3315 That is said to make things like for (;;) statements work
3318 fprintf_unfiltered (gdb_stdlog, "infrun: stepped to a different line\n");
3320 print_stop_reason (END_STEPPING_RANGE, 0);
3321 stop_stepping (ecs);
3325 /* We aren't done stepping.
3327 Optimize by setting the stepping range to the line.
3328 (We might not be in the original line, but if we entered a
3329 new line in mid-statement, we continue stepping. This makes
3330 things like for(;;) statements work better.) */
3332 ecs->event_thread->step_range_start = stop_pc_sal.pc;
3333 ecs->event_thread->step_range_end = stop_pc_sal.end;
3334 ecs->event_thread->step_frame_id = get_frame_id (get_current_frame ());
3335 ecs->event_thread->current_line = stop_pc_sal.line;
3336 ecs->event_thread->current_symtab = stop_pc_sal.symtab;
3339 fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
3343 /* Are we in the middle of stepping? */
3346 currently_stepping (struct thread_info *tp)
3348 return (((tp->step_range_end && tp->step_resume_breakpoint == NULL)
3349 || tp->trap_expected)
3350 || tp->stepping_through_solib_after_catch
3351 || bpstat_should_step ());
3354 /* Subroutine call with source code we should not step over. Do step
3355 to the first line of code in it. */
3358 step_into_function (struct execution_control_state *ecs)
3361 struct symtab_and_line stop_func_sal, sr_sal;
3363 s = find_pc_symtab (stop_pc);
3364 if (s && s->language != language_asm)
3365 ecs->stop_func_start = gdbarch_skip_prologue
3366 (current_gdbarch, ecs->stop_func_start);
3368 stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
3369 /* Use the step_resume_break to step until the end of the prologue,
3370 even if that involves jumps (as it seems to on the vax under
3372 /* If the prologue ends in the middle of a source line, continue to
3373 the end of that source line (if it is still within the function).
3374 Otherwise, just go to end of prologue. */
3375 if (stop_func_sal.end
3376 && stop_func_sal.pc != ecs->stop_func_start
3377 && stop_func_sal.end < ecs->stop_func_end)
3378 ecs->stop_func_start = stop_func_sal.end;
3380 /* Architectures which require breakpoint adjustment might not be able
3381 to place a breakpoint at the computed address. If so, the test
3382 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
3383 ecs->stop_func_start to an address at which a breakpoint may be
3384 legitimately placed.
3386 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
3387 made, GDB will enter an infinite loop when stepping through
3388 optimized code consisting of VLIW instructions which contain
3389 subinstructions corresponding to different source lines. On
3390 FR-V, it's not permitted to place a breakpoint on any but the
3391 first subinstruction of a VLIW instruction. When a breakpoint is
3392 set, GDB will adjust the breakpoint address to the beginning of
3393 the VLIW instruction. Thus, we need to make the corresponding
3394 adjustment here when computing the stop address. */
3396 if (gdbarch_adjust_breakpoint_address_p (current_gdbarch))
3398 ecs->stop_func_start
3399 = gdbarch_adjust_breakpoint_address (current_gdbarch,
3400 ecs->stop_func_start);
3403 if (ecs->stop_func_start == stop_pc)
3405 /* We are already there: stop now. */
3407 print_stop_reason (END_STEPPING_RANGE, 0);
3408 stop_stepping (ecs);
3413 /* Put the step-breakpoint there and go until there. */
3414 init_sal (&sr_sal); /* initialize to zeroes */
3415 sr_sal.pc = ecs->stop_func_start;
3416 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
3418 /* Do not specify what the fp should be when we stop since on
3419 some machines the prologue is where the new fp value is
3421 insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
3423 /* And make sure stepping stops right away then. */
3424 ecs->event_thread->step_range_end = ecs->event_thread->step_range_start;
3429 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
3430 This is used to both functions and to skip over code. */
3433 insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
3434 struct frame_id sr_id)
3436 /* There should never be more than one step-resume or longjmp-resume
3437 breakpoint per thread, so we should never be setting a new
3438 step_resume_breakpoint when one is already active. */
3439 gdb_assert (inferior_thread ()->step_resume_breakpoint == NULL);
3442 fprintf_unfiltered (gdb_stdlog,
3443 "infrun: inserting step-resume breakpoint at 0x%s\n",
3444 paddr_nz (sr_sal.pc));
3446 inferior_thread ()->step_resume_breakpoint
3447 = set_momentary_breakpoint (sr_sal, sr_id, bp_step_resume);
3450 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
3451 to skip a potential signal handler.
3453 This is called with the interrupted function's frame. The signal
3454 handler, when it returns, will resume the interrupted function at
3458 insert_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
3460 struct symtab_and_line sr_sal;
3462 gdb_assert (return_frame != NULL);
3463 init_sal (&sr_sal); /* initialize to zeros */
3465 sr_sal.pc = gdbarch_addr_bits_remove
3466 (current_gdbarch, get_frame_pc (return_frame));
3467 sr_sal.section = find_pc_overlay (sr_sal.pc);
3469 insert_step_resume_breakpoint_at_sal (sr_sal, get_frame_id (return_frame));
3472 /* Similar to insert_step_resume_breakpoint_at_frame, except
3473 but a breakpoint at the previous frame's PC. This is used to
3474 skip a function after stepping into it (for "next" or if the called
3475 function has no debugging information).
3477 The current function has almost always been reached by single
3478 stepping a call or return instruction. NEXT_FRAME belongs to the
3479 current function, and the breakpoint will be set at the caller's
3482 This is a separate function rather than reusing
3483 insert_step_resume_breakpoint_at_frame in order to avoid
3484 get_prev_frame, which may stop prematurely (see the implementation
3485 of frame_unwind_id for an example). */
3488 insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
3490 struct symtab_and_line sr_sal;
3492 /* We shouldn't have gotten here if we don't know where the call site
3494 gdb_assert (frame_id_p (frame_unwind_id (next_frame)));
3496 init_sal (&sr_sal); /* initialize to zeros */
3498 sr_sal.pc = gdbarch_addr_bits_remove
3499 (current_gdbarch, frame_pc_unwind (next_frame));
3500 sr_sal.section = find_pc_overlay (sr_sal.pc);
3502 insert_step_resume_breakpoint_at_sal (sr_sal, frame_unwind_id (next_frame));
3505 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
3506 new breakpoint at the target of a jmp_buf. The handling of
3507 longjmp-resume uses the same mechanisms used for handling
3508 "step-resume" breakpoints. */
3511 insert_longjmp_resume_breakpoint (CORE_ADDR pc)
3513 /* There should never be more than one step-resume or longjmp-resume
3514 breakpoint per thread, so we should never be setting a new
3515 longjmp_resume_breakpoint when one is already active. */
3516 gdb_assert (inferior_thread ()->step_resume_breakpoint == NULL);
3519 fprintf_unfiltered (gdb_stdlog,
3520 "infrun: inserting longjmp-resume breakpoint at 0x%s\n",
3523 inferior_thread ()->step_resume_breakpoint =
3524 set_momentary_breakpoint_at_pc (pc, bp_longjmp_resume);
3528 stop_stepping (struct execution_control_state *ecs)
3531 fprintf_unfiltered (gdb_stdlog, "infrun: stop_stepping\n");
3533 /* Let callers know we don't want to wait for the inferior anymore. */
3534 ecs->wait_some_more = 0;
3537 /* This function handles various cases where we need to continue
3538 waiting for the inferior. */
3539 /* (Used to be the keep_going: label in the old wait_for_inferior) */
3542 keep_going (struct execution_control_state *ecs)
3544 /* Save the pc before execution, to compare with pc after stop. */
3545 ecs->event_thread->prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
3547 /* If we did not do break;, it means we should keep running the
3548 inferior and not return to debugger. */
3550 if (ecs->event_thread->trap_expected
3551 && ecs->event_thread->stop_signal != TARGET_SIGNAL_TRAP)
3553 /* We took a signal (which we are supposed to pass through to
3554 the inferior, else we'd not get here) and we haven't yet
3555 gotten our trap. Simply continue. */
3556 resume (currently_stepping (ecs->event_thread),
3557 ecs->event_thread->stop_signal);
3561 /* Either the trap was not expected, but we are continuing
3562 anyway (the user asked that this signal be passed to the
3565 The signal was SIGTRAP, e.g. it was our signal, but we
3566 decided we should resume from it.
3568 We're going to run this baby now!
3570 Note that insert_breakpoints won't try to re-insert
3571 already inserted breakpoints. Therefore, we don't
3572 care if breakpoints were already inserted, or not. */
3574 if (ecs->event_thread->stepping_over_breakpoint)
3576 if (! use_displaced_stepping (current_gdbarch))
3577 /* Since we can't do a displaced step, we have to remove
3578 the breakpoint while we step it. To keep things
3579 simple, we remove them all. */
3580 remove_breakpoints ();
3584 struct gdb_exception e;
3585 /* Stop stepping when inserting breakpoints
3587 TRY_CATCH (e, RETURN_MASK_ERROR)
3589 insert_breakpoints ();
3593 stop_stepping (ecs);
3598 ecs->event_thread->trap_expected = ecs->event_thread->stepping_over_breakpoint;
3600 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3601 specifies that such a signal should be delivered to the
3604 Typically, this would occure when a user is debugging a
3605 target monitor on a simulator: the target monitor sets a
3606 breakpoint; the simulator encounters this break-point and
3607 halts the simulation handing control to GDB; GDB, noteing
3608 that the break-point isn't valid, returns control back to the
3609 simulator; the simulator then delivers the hardware
3610 equivalent of a SIGNAL_TRAP to the program being debugged. */
3612 if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
3613 && !signal_program[ecs->event_thread->stop_signal])
3614 ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
3616 resume (currently_stepping (ecs->event_thread),
3617 ecs->event_thread->stop_signal);
3620 prepare_to_wait (ecs);
3623 /* This function normally comes after a resume, before
3624 handle_inferior_event exits. It takes care of any last bits of
3625 housekeeping, and sets the all-important wait_some_more flag. */
3628 prepare_to_wait (struct execution_control_state *ecs)
3631 fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
3632 if (infwait_state == infwait_normal_state)
3634 overlay_cache_invalid = 1;
3636 /* We have to invalidate the registers BEFORE calling
3637 target_wait because they can be loaded from the target while
3638 in target_wait. This makes remote debugging a bit more
3639 efficient for those targets that provide critical registers
3640 as part of their normal status mechanism. */
3642 registers_changed ();
3643 waiton_ptid = pid_to_ptid (-1);
3645 /* This is the old end of the while loop. Let everybody know we
3646 want to wait for the inferior some more and get called again
3648 ecs->wait_some_more = 1;
3651 /* Print why the inferior has stopped. We always print something when
3652 the inferior exits, or receives a signal. The rest of the cases are
3653 dealt with later on in normal_stop() and print_it_typical(). Ideally
3654 there should be a call to this function from handle_inferior_event()
3655 each time stop_stepping() is called.*/
3657 print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
3659 switch (stop_reason)
3661 case END_STEPPING_RANGE:
3662 /* We are done with a step/next/si/ni command. */
3663 /* For now print nothing. */
3664 /* Print a message only if not in the middle of doing a "step n"
3665 operation for n > 1 */
3666 if (!step_multi || !stop_step)
3667 if (ui_out_is_mi_like_p (uiout))
3670 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
3673 /* The inferior was terminated by a signal. */
3674 annotate_signalled ();
3675 if (ui_out_is_mi_like_p (uiout))
3678 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
3679 ui_out_text (uiout, "\nProgram terminated with signal ");
3680 annotate_signal_name ();
3681 ui_out_field_string (uiout, "signal-name",
3682 target_signal_to_name (stop_info));
3683 annotate_signal_name_end ();
3684 ui_out_text (uiout, ", ");
3685 annotate_signal_string ();
3686 ui_out_field_string (uiout, "signal-meaning",
3687 target_signal_to_string (stop_info));
3688 annotate_signal_string_end ();
3689 ui_out_text (uiout, ".\n");
3690 ui_out_text (uiout, "The program no longer exists.\n");
3693 /* The inferior program is finished. */
3694 annotate_exited (stop_info);
3697 if (ui_out_is_mi_like_p (uiout))
3698 ui_out_field_string (uiout, "reason",
3699 async_reason_lookup (EXEC_ASYNC_EXITED));
3700 ui_out_text (uiout, "\nProgram exited with code ");
3701 ui_out_field_fmt (uiout, "exit-code", "0%o",
3702 (unsigned int) stop_info);
3703 ui_out_text (uiout, ".\n");
3707 if (ui_out_is_mi_like_p (uiout))
3710 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
3711 ui_out_text (uiout, "\nProgram exited normally.\n");
3713 /* Support the --return-child-result option. */
3714 return_child_result_value = stop_info;
3716 case SIGNAL_RECEIVED:
3717 /* Signal received. The signal table tells us to print about
3720 ui_out_text (uiout, "\nProgram received signal ");
3721 annotate_signal_name ();
3722 if (ui_out_is_mi_like_p (uiout))
3724 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
3725 ui_out_field_string (uiout, "signal-name",
3726 target_signal_to_name (stop_info));
3727 annotate_signal_name_end ();
3728 ui_out_text (uiout, ", ");
3729 annotate_signal_string ();
3730 ui_out_field_string (uiout, "signal-meaning",
3731 target_signal_to_string (stop_info));
3732 annotate_signal_string_end ();
3733 ui_out_text (uiout, ".\n");
3736 internal_error (__FILE__, __LINE__,
3737 _("print_stop_reason: unrecognized enum value"));
3743 /* Here to return control to GDB when the inferior stops for real.
3744 Print appropriate messages, remove breakpoints, give terminal our modes.
3746 STOP_PRINT_FRAME nonzero means print the executing frame
3747 (pc, function, args, file, line number and line text).
3748 BREAKPOINTS_FAILED nonzero means stop was due to error
3749 attempting to insert breakpoints. */
3754 struct target_waitstatus last;
3757 get_last_target_status (&last_ptid, &last);
3759 /* In non-stop mode, we don't want GDB to switch threads behind the
3760 user's back, to avoid races where the user is typing a command to
3761 apply to thread x, but GDB switches to thread y before the user
3762 finishes entering the command. */
3764 /* As with the notification of thread events, we want to delay
3765 notifying the user that we've switched thread context until
3766 the inferior actually stops.
3768 There's no point in saying anything if the inferior has exited.
3769 Note that SIGNALLED here means "exited with a signal", not
3770 "received a signal". */
3772 && !ptid_equal (previous_inferior_ptid, inferior_ptid)
3773 && target_has_execution
3774 && last.kind != TARGET_WAITKIND_SIGNALLED
3775 && last.kind != TARGET_WAITKIND_EXITED)
3777 target_terminal_ours_for_output ();
3778 printf_filtered (_("[Switching to %s]\n"),
3779 target_pid_to_str (inferior_ptid));
3780 annotate_thread_changed ();
3781 previous_inferior_ptid = inferior_ptid;
3784 /* NOTE drow/2004-01-17: Is this still necessary? */
3785 /* Make sure that the current_frame's pc is correct. This
3786 is a correction for setting up the frame info before doing
3787 gdbarch_decr_pc_after_break */
3788 if (target_has_execution)
3789 /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
3790 gdbarch_decr_pc_after_break, the program counter can change. Ask the
3791 frame code to check for this and sort out any resultant mess.
3792 gdbarch_decr_pc_after_break needs to just go away. */
3793 deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
3795 if (!breakpoints_always_inserted_mode () && target_has_execution)
3797 if (remove_breakpoints ())
3799 target_terminal_ours_for_output ();
3800 printf_filtered (_("\
3801 Cannot remove breakpoints because program is no longer writable.\n\
3802 It might be running in another process.\n\
3803 Further execution is probably impossible.\n"));
3807 /* If an auto-display called a function and that got a signal,
3808 delete that auto-display to avoid an infinite recursion. */
3810 if (stopped_by_random_signal)
3811 disable_current_display ();
3813 /* Don't print a message if in the middle of doing a "step n"
3814 operation for n > 1 */
3815 if (step_multi && stop_step)
3818 target_terminal_ours ();
3820 /* Set the current source location. This will also happen if we
3821 display the frame below, but the current SAL will be incorrect
3822 during a user hook-stop function. */
3823 if (target_has_stack && !stop_stack_dummy)
3824 set_current_sal_from_frame (get_current_frame (), 1);
3826 /* Look up the hook_stop and run it (CLI internally handles problem
3827 of stop_command's pre-hook not existing). */
3829 catch_errors (hook_stop_stub, stop_command,
3830 "Error while running hook_stop:\n", RETURN_MASK_ALL);
3832 if (!target_has_stack)
3838 if (last.kind == TARGET_WAITKIND_SIGNALLED
3839 || last.kind == TARGET_WAITKIND_EXITED)
3842 /* Select innermost stack frame - i.e., current frame is frame 0,
3843 and current location is based on that.
3844 Don't do this on return from a stack dummy routine,
3845 or if the program has exited. */
3847 if (!stop_stack_dummy)
3849 select_frame (get_current_frame ());
3851 /* Print current location without a level number, if
3852 we have changed functions or hit a breakpoint.
3853 Print source line if we have one.
3854 bpstat_print() contains the logic deciding in detail
3855 what to print, based on the event(s) that just occurred. */
3857 /* If --batch-silent is enabled then there's no need to print the current
3858 source location, and to try risks causing an error message about
3859 missing source files. */
3860 if (stop_print_frame && !batch_silent)
3864 int do_frame_printing = 1;
3865 struct thread_info *tp = inferior_thread ();
3867 bpstat_ret = bpstat_print (tp->stop_bpstat);
3871 /* If we had hit a shared library event breakpoint,
3872 bpstat_print would print out this message. If we hit
3873 an OS-level shared library event, do the same
3875 if (last.kind == TARGET_WAITKIND_LOADED)
3877 printf_filtered (_("Stopped due to shared library event\n"));
3878 source_flag = SRC_LINE; /* something bogus */
3879 do_frame_printing = 0;
3883 /* FIXME: cagney/2002-12-01: Given that a frame ID does
3884 (or should) carry around the function and does (or
3885 should) use that when doing a frame comparison. */
3887 && frame_id_eq (tp->step_frame_id,
3888 get_frame_id (get_current_frame ()))
3889 && step_start_function == find_pc_function (stop_pc))
3890 source_flag = SRC_LINE; /* finished step, just print source line */
3892 source_flag = SRC_AND_LOC; /* print location and source line */
3894 case PRINT_SRC_AND_LOC:
3895 source_flag = SRC_AND_LOC; /* print location and source line */
3897 case PRINT_SRC_ONLY:
3898 source_flag = SRC_LINE;
3901 source_flag = SRC_LINE; /* something bogus */
3902 do_frame_printing = 0;
3905 internal_error (__FILE__, __LINE__, _("Unknown value."));
3908 if (ui_out_is_mi_like_p (uiout))
3911 ui_out_field_int (uiout, "thread-id",
3912 pid_to_thread_id (inferior_ptid));
3915 struct cleanup *back_to = make_cleanup_ui_out_list_begin_end
3916 (uiout, "stopped-threads");
3917 ui_out_field_int (uiout, NULL,
3918 pid_to_thread_id (inferior_ptid));
3919 do_cleanups (back_to);
3922 ui_out_field_string (uiout, "stopped-threads", "all");
3924 /* The behavior of this routine with respect to the source
3926 SRC_LINE: Print only source line
3927 LOCATION: Print only location
3928 SRC_AND_LOC: Print location and source line */
3929 if (do_frame_printing)
3930 print_stack_frame (get_selected_frame (NULL), 0, source_flag);
3932 /* Display the auto-display expressions. */
3937 /* Save the function value return registers, if we care.
3938 We might be about to restore their previous contents. */
3939 if (inferior_thread ()->proceed_to_finish)
3941 /* This should not be necessary. */
3943 regcache_xfree (stop_registers);
3945 /* NB: The copy goes through to the target picking up the value of
3946 all the registers. */
3947 stop_registers = regcache_dup (get_current_regcache ());
3950 if (stop_stack_dummy)
3952 /* Pop the empty frame that contains the stack dummy. POP_FRAME
3953 ends with a setting of the current frame, so we can use that
3955 frame_pop (get_current_frame ());
3956 /* Set stop_pc to what it was before we called the function.
3957 Can't rely on restore_inferior_status because that only gets
3958 called if we don't stop in the called function. */
3959 stop_pc = read_pc ();
3960 select_frame (get_current_frame ());
3964 annotate_stopped ();
3965 if (!suppress_stop_observer && !step_multi)
3967 if (!ptid_equal (inferior_ptid, null_ptid))
3968 observer_notify_normal_stop (inferior_thread ()->stop_bpstat);
3970 observer_notify_normal_stop (NULL);
3972 if (target_has_execution
3973 && last.kind != TARGET_WAITKIND_SIGNALLED
3974 && last.kind != TARGET_WAITKIND_EXITED)
3976 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3977 Delete any breakpoint that is to be deleted at the next stop. */
3978 breakpoint_auto_delete (inferior_thread ()->stop_bpstat);
3981 set_running (pid_to_ptid (-1), 0);
3983 set_running (inferior_ptid, 0);
3988 hook_stop_stub (void *cmd)
3990 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
3995 signal_stop_state (int signo)
3997 /* Always stop on signals if we're just gaining control of the
3999 return signal_stop[signo] || stop_soon != NO_STOP_QUIETLY;
4003 signal_print_state (int signo)
4005 return signal_print[signo];
4009 signal_pass_state (int signo)
4011 return signal_program[signo];
4015 signal_stop_update (int signo, int state)
4017 int ret = signal_stop[signo];
4018 signal_stop[signo] = state;
4023 signal_print_update (int signo, int state)
4025 int ret = signal_print[signo];
4026 signal_print[signo] = state;
4031 signal_pass_update (int signo, int state)
4033 int ret = signal_program[signo];
4034 signal_program[signo] = state;
4039 sig_print_header (void)
4041 printf_filtered (_("\
4042 Signal Stop\tPrint\tPass to program\tDescription\n"));
4046 sig_print_info (enum target_signal oursig)
4048 char *name = target_signal_to_name (oursig);
4049 int name_padding = 13 - strlen (name);
4051 if (name_padding <= 0)
4054 printf_filtered ("%s", name);
4055 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
4056 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
4057 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
4058 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
4059 printf_filtered ("%s\n", target_signal_to_string (oursig));
4062 /* Specify how various signals in the inferior should be handled. */
4065 handle_command (char *args, int from_tty)
4068 int digits, wordlen;
4069 int sigfirst, signum, siglast;
4070 enum target_signal oursig;
4073 unsigned char *sigs;
4074 struct cleanup *old_chain;
4078 error_no_arg (_("signal to handle"));
4081 /* Allocate and zero an array of flags for which signals to handle. */
4083 nsigs = (int) TARGET_SIGNAL_LAST;
4084 sigs = (unsigned char *) alloca (nsigs);
4085 memset (sigs, 0, nsigs);
4087 /* Break the command line up into args. */
4089 argv = buildargv (args);
4094 old_chain = make_cleanup_freeargv (argv);
4096 /* Walk through the args, looking for signal oursigs, signal names, and
4097 actions. Signal numbers and signal names may be interspersed with
4098 actions, with the actions being performed for all signals cumulatively
4099 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
4101 while (*argv != NULL)
4103 wordlen = strlen (*argv);
4104 for (digits = 0; isdigit ((*argv)[digits]); digits++)
4108 sigfirst = siglast = -1;
4110 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
4112 /* Apply action to all signals except those used by the
4113 debugger. Silently skip those. */
4116 siglast = nsigs - 1;
4118 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
4120 SET_SIGS (nsigs, sigs, signal_stop);
4121 SET_SIGS (nsigs, sigs, signal_print);
4123 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
4125 UNSET_SIGS (nsigs, sigs, signal_program);
4127 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
4129 SET_SIGS (nsigs, sigs, signal_print);
4131 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
4133 SET_SIGS (nsigs, sigs, signal_program);
4135 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
4137 UNSET_SIGS (nsigs, sigs, signal_stop);
4139 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
4141 SET_SIGS (nsigs, sigs, signal_program);
4143 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
4145 UNSET_SIGS (nsigs, sigs, signal_print);
4146 UNSET_SIGS (nsigs, sigs, signal_stop);
4148 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
4150 UNSET_SIGS (nsigs, sigs, signal_program);
4152 else if (digits > 0)
4154 /* It is numeric. The numeric signal refers to our own
4155 internal signal numbering from target.h, not to host/target
4156 signal number. This is a feature; users really should be
4157 using symbolic names anyway, and the common ones like
4158 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
4160 sigfirst = siglast = (int)
4161 target_signal_from_command (atoi (*argv));
4162 if ((*argv)[digits] == '-')
4165 target_signal_from_command (atoi ((*argv) + digits + 1));
4167 if (sigfirst > siglast)
4169 /* Bet he didn't figure we'd think of this case... */
4177 oursig = target_signal_from_name (*argv);
4178 if (oursig != TARGET_SIGNAL_UNKNOWN)
4180 sigfirst = siglast = (int) oursig;
4184 /* Not a number and not a recognized flag word => complain. */
4185 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
4189 /* If any signal numbers or symbol names were found, set flags for
4190 which signals to apply actions to. */
4192 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
4194 switch ((enum target_signal) signum)
4196 case TARGET_SIGNAL_TRAP:
4197 case TARGET_SIGNAL_INT:
4198 if (!allsigs && !sigs[signum])
4200 if (query ("%s is used by the debugger.\n\
4201 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal) signum)))
4207 printf_unfiltered (_("Not confirmed, unchanged.\n"));
4208 gdb_flush (gdb_stdout);
4212 case TARGET_SIGNAL_0:
4213 case TARGET_SIGNAL_DEFAULT:
4214 case TARGET_SIGNAL_UNKNOWN:
4215 /* Make sure that "all" doesn't print these. */
4226 target_notice_signals (inferior_ptid);
4230 /* Show the results. */
4231 sig_print_header ();
4232 for (signum = 0; signum < nsigs; signum++)
4236 sig_print_info (signum);
4241 do_cleanups (old_chain);
4245 xdb_handle_command (char *args, int from_tty)
4248 struct cleanup *old_chain;
4250 /* Break the command line up into args. */
4252 argv = buildargv (args);
4257 old_chain = make_cleanup_freeargv (argv);
4258 if (argv[1] != (char *) NULL)
4263 bufLen = strlen (argv[0]) + 20;
4264 argBuf = (char *) xmalloc (bufLen);
4268 enum target_signal oursig;
4270 oursig = target_signal_from_name (argv[0]);
4271 memset (argBuf, 0, bufLen);
4272 if (strcmp (argv[1], "Q") == 0)
4273 sprintf (argBuf, "%s %s", argv[0], "noprint");
4276 if (strcmp (argv[1], "s") == 0)
4278 if (!signal_stop[oursig])
4279 sprintf (argBuf, "%s %s", argv[0], "stop");
4281 sprintf (argBuf, "%s %s", argv[0], "nostop");
4283 else if (strcmp (argv[1], "i") == 0)
4285 if (!signal_program[oursig])
4286 sprintf (argBuf, "%s %s", argv[0], "pass");
4288 sprintf (argBuf, "%s %s", argv[0], "nopass");
4290 else if (strcmp (argv[1], "r") == 0)
4292 if (!signal_print[oursig])
4293 sprintf (argBuf, "%s %s", argv[0], "print");
4295 sprintf (argBuf, "%s %s", argv[0], "noprint");
4301 handle_command (argBuf, from_tty);
4303 printf_filtered (_("Invalid signal handling flag.\n"));
4308 do_cleanups (old_chain);
4311 /* Print current contents of the tables set by the handle command.
4312 It is possible we should just be printing signals actually used
4313 by the current target (but for things to work right when switching
4314 targets, all signals should be in the signal tables). */
4317 signals_info (char *signum_exp, int from_tty)
4319 enum target_signal oursig;
4320 sig_print_header ();
4324 /* First see if this is a symbol name. */
4325 oursig = target_signal_from_name (signum_exp);
4326 if (oursig == TARGET_SIGNAL_UNKNOWN)
4328 /* No, try numeric. */
4330 target_signal_from_command (parse_and_eval_long (signum_exp));
4332 sig_print_info (oursig);
4336 printf_filtered ("\n");
4337 /* These ugly casts brought to you by the native VAX compiler. */
4338 for (oursig = TARGET_SIGNAL_FIRST;
4339 (int) oursig < (int) TARGET_SIGNAL_LAST;
4340 oursig = (enum target_signal) ((int) oursig + 1))
4344 if (oursig != TARGET_SIGNAL_UNKNOWN
4345 && oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0)
4346 sig_print_info (oursig);
4349 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
4352 struct inferior_status
4354 enum target_signal stop_signal;
4358 int stop_stack_dummy;
4359 int stopped_by_random_signal;
4360 int stepping_over_breakpoint;
4361 CORE_ADDR step_range_start;
4362 CORE_ADDR step_range_end;
4363 struct frame_id step_frame_id;
4364 enum step_over_calls_kind step_over_calls;
4365 CORE_ADDR step_resume_break_address;
4366 int stop_after_trap;
4369 /* These are here because if call_function_by_hand has written some
4370 registers and then decides to call error(), we better not have changed
4372 struct regcache *registers;
4374 /* A frame unique identifier. */
4375 struct frame_id selected_frame_id;
4377 int breakpoint_proceeded;
4378 int restore_stack_info;
4379 int proceed_to_finish;
4383 write_inferior_status_register (struct inferior_status *inf_status, int regno,
4386 int size = register_size (current_gdbarch, regno);
4387 void *buf = alloca (size);
4388 store_signed_integer (buf, size, val);
4389 regcache_raw_write (inf_status->registers, regno, buf);
4392 /* Save all of the information associated with the inferior<==>gdb
4393 connection. INF_STATUS is a pointer to a "struct inferior_status"
4394 (defined in inferior.h). */
4396 struct inferior_status *
4397 save_inferior_status (int restore_stack_info)
4399 struct inferior_status *inf_status = XMALLOC (struct inferior_status);
4400 struct thread_info *tp = inferior_thread ();
4402 inf_status->stop_signal = tp->stop_signal;
4403 inf_status->stop_pc = stop_pc;
4404 inf_status->stop_step = stop_step;
4405 inf_status->stop_stack_dummy = stop_stack_dummy;
4406 inf_status->stopped_by_random_signal = stopped_by_random_signal;
4407 inf_status->stepping_over_breakpoint = tp->trap_expected;
4408 inf_status->step_range_start = tp->step_range_start;
4409 inf_status->step_range_end = tp->step_range_end;
4410 inf_status->step_frame_id = tp->step_frame_id;
4411 inf_status->step_over_calls = tp->step_over_calls;
4412 inf_status->stop_after_trap = stop_after_trap;
4413 inf_status->stop_soon = stop_soon;
4414 /* Save original bpstat chain here; replace it with copy of chain.
4415 If caller's caller is walking the chain, they'll be happier if we
4416 hand them back the original chain when restore_inferior_status is
4418 inf_status->stop_bpstat = tp->stop_bpstat;
4419 tp->stop_bpstat = bpstat_copy (tp->stop_bpstat);
4420 inf_status->breakpoint_proceeded = breakpoint_proceeded;
4421 inf_status->restore_stack_info = restore_stack_info;
4422 inf_status->proceed_to_finish = tp->proceed_to_finish;
4424 inf_status->registers = regcache_dup (get_current_regcache ());
4426 inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
4431 restore_selected_frame (void *args)
4433 struct frame_id *fid = (struct frame_id *) args;
4434 struct frame_info *frame;
4436 frame = frame_find_by_id (*fid);
4438 /* If inf_status->selected_frame_id is NULL, there was no previously
4442 warning (_("Unable to restore previously selected frame."));
4446 select_frame (frame);
4452 restore_inferior_status (struct inferior_status *inf_status)
4454 struct thread_info *tp = inferior_thread ();
4456 tp->stop_signal = inf_status->stop_signal;
4457 stop_pc = inf_status->stop_pc;
4458 stop_step = inf_status->stop_step;
4459 stop_stack_dummy = inf_status->stop_stack_dummy;
4460 stopped_by_random_signal = inf_status->stopped_by_random_signal;
4461 tp->trap_expected = inf_status->stepping_over_breakpoint;
4462 tp->step_range_start = inf_status->step_range_start;
4463 tp->step_range_end = inf_status->step_range_end;
4464 tp->step_frame_id = inf_status->step_frame_id;
4465 tp->step_over_calls = inf_status->step_over_calls;
4466 stop_after_trap = inf_status->stop_after_trap;
4467 stop_soon = inf_status->stop_soon;
4468 bpstat_clear (&tp->stop_bpstat);
4469 tp->stop_bpstat = inf_status->stop_bpstat;
4470 breakpoint_proceeded = inf_status->breakpoint_proceeded;
4471 tp->proceed_to_finish = inf_status->proceed_to_finish;
4473 /* The inferior can be gone if the user types "print exit(0)"
4474 (and perhaps other times). */
4475 if (target_has_execution)
4476 /* NB: The register write goes through to the target. */
4477 regcache_cpy (get_current_regcache (), inf_status->registers);
4478 regcache_xfree (inf_status->registers);
4480 /* FIXME: If we are being called after stopping in a function which
4481 is called from gdb, we should not be trying to restore the
4482 selected frame; it just prints a spurious error message (The
4483 message is useful, however, in detecting bugs in gdb (like if gdb
4484 clobbers the stack)). In fact, should we be restoring the
4485 inferior status at all in that case? . */
4487 if (target_has_stack && inf_status->restore_stack_info)
4489 /* The point of catch_errors is that if the stack is clobbered,
4490 walking the stack might encounter a garbage pointer and
4491 error() trying to dereference it. */
4493 (restore_selected_frame, &inf_status->selected_frame_id,
4494 "Unable to restore previously selected frame:\n",
4495 RETURN_MASK_ERROR) == 0)
4496 /* Error in restoring the selected frame. Select the innermost
4498 select_frame (get_current_frame ());
4506 do_restore_inferior_status_cleanup (void *sts)
4508 restore_inferior_status (sts);
4512 make_cleanup_restore_inferior_status (struct inferior_status *inf_status)
4514 return make_cleanup (do_restore_inferior_status_cleanup, inf_status);
4518 discard_inferior_status (struct inferior_status *inf_status)
4520 /* See save_inferior_status for info on stop_bpstat. */
4521 bpstat_clear (&inf_status->stop_bpstat);
4522 regcache_xfree (inf_status->registers);
4527 inferior_has_forked (ptid_t pid, ptid_t *child_pid)
4529 struct target_waitstatus last;
4532 get_last_target_status (&last_ptid, &last);
4534 if (last.kind != TARGET_WAITKIND_FORKED)
4537 if (!ptid_equal (last_ptid, pid))
4540 *child_pid = last.value.related_pid;
4545 inferior_has_vforked (ptid_t pid, ptid_t *child_pid)
4547 struct target_waitstatus last;
4550 get_last_target_status (&last_ptid, &last);
4552 if (last.kind != TARGET_WAITKIND_VFORKED)
4555 if (!ptid_equal (last_ptid, pid))
4558 *child_pid = last.value.related_pid;
4563 inferior_has_execd (ptid_t pid, char **execd_pathname)
4565 struct target_waitstatus last;
4568 get_last_target_status (&last_ptid, &last);
4570 if (last.kind != TARGET_WAITKIND_EXECD)
4573 if (!ptid_equal (last_ptid, pid))
4576 *execd_pathname = xstrdup (last.value.execd_pathname);
4580 /* Oft used ptids */
4582 ptid_t minus_one_ptid;
4584 /* Create a ptid given the necessary PID, LWP, and TID components. */
4587 ptid_build (int pid, long lwp, long tid)
4597 /* Create a ptid from just a pid. */
4600 pid_to_ptid (int pid)
4602 return ptid_build (pid, 0, 0);
4605 /* Fetch the pid (process id) component from a ptid. */
4608 ptid_get_pid (ptid_t ptid)
4613 /* Fetch the lwp (lightweight process) component from a ptid. */
4616 ptid_get_lwp (ptid_t ptid)
4621 /* Fetch the tid (thread id) component from a ptid. */
4624 ptid_get_tid (ptid_t ptid)
4629 /* ptid_equal() is used to test equality of two ptids. */
4632 ptid_equal (ptid_t ptid1, ptid_t ptid2)
4634 return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp
4635 && ptid1.tid == ptid2.tid);
4638 /* restore_inferior_ptid() will be used by the cleanup machinery
4639 to restore the inferior_ptid value saved in a call to
4640 save_inferior_ptid(). */
4643 restore_inferior_ptid (void *arg)
4645 ptid_t *saved_ptid_ptr = arg;
4646 inferior_ptid = *saved_ptid_ptr;
4650 /* Save the value of inferior_ptid so that it may be restored by a
4651 later call to do_cleanups(). Returns the struct cleanup pointer
4652 needed for later doing the cleanup. */
4655 save_inferior_ptid (void)
4657 ptid_t *saved_ptid_ptr;
4659 saved_ptid_ptr = xmalloc (sizeof (ptid_t));
4660 *saved_ptid_ptr = inferior_ptid;
4661 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
4666 static int non_stop_1 = 0;
4669 set_non_stop (char *args, int from_tty,
4670 struct cmd_list_element *c)
4672 if (target_has_execution)
4674 non_stop_1 = non_stop;
4675 error (_("Cannot change this setting while the inferior is running."));
4678 non_stop = non_stop_1;
4682 show_non_stop (struct ui_file *file, int from_tty,
4683 struct cmd_list_element *c, const char *value)
4685 fprintf_filtered (file,
4686 _("Controlling the inferior in non-stop mode is %s.\n"),
4692 _initialize_infrun (void)
4696 struct cmd_list_element *c;
4698 add_info ("signals", 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_info_alias ("handle", "signals", 0);
4703 add_com ("handle", class_run, handle_command, _("\
4704 Specify how to handle a signal.\n\
4705 Args are signals and actions to apply to those signals.\n\
4706 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4707 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4708 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4709 The special arg \"all\" is recognized to mean all signals except those\n\
4710 used by the debugger, typically SIGTRAP and SIGINT.\n\
4711 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4712 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4713 Stop means reenter debugger if this signal happens (implies print).\n\
4714 Print means print a message if this signal happens.\n\
4715 Pass means let program see this signal; otherwise program doesn't know.\n\
4716 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4717 Pass and Stop may be combined."));
4720 add_com ("lz", class_info, signals_info, _("\
4721 What debugger does when program gets various signals.\n\
4722 Specify a signal as argument to print info on that signal only."));
4723 add_com ("z", class_run, xdb_handle_command, _("\
4724 Specify how to handle a signal.\n\
4725 Args are signals and actions to apply to those signals.\n\
4726 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4727 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4728 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4729 The special arg \"all\" is recognized to mean all signals except those\n\
4730 used by the debugger, typically SIGTRAP and SIGINT.\n\
4731 Recognized actions include \"s\" (toggles between stop and nostop), \n\
4732 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4733 nopass), \"Q\" (noprint)\n\
4734 Stop means reenter debugger if this signal happens (implies print).\n\
4735 Print means print a message if this signal happens.\n\
4736 Pass means let program see this signal; otherwise program doesn't know.\n\
4737 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4738 Pass and Stop may be combined."));
4742 stop_command = add_cmd ("stop", class_obscure,
4743 not_just_help_class_command, _("\
4744 There is no `stop' command, but you can set a hook on `stop'.\n\
4745 This allows you to set a list of commands to be run each time execution\n\
4746 of the program stops."), &cmdlist);
4748 add_setshow_zinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
4749 Set inferior debugging."), _("\
4750 Show inferior debugging."), _("\
4751 When non-zero, inferior specific debugging is enabled."),
4754 &setdebuglist, &showdebuglist);
4756 add_setshow_boolean_cmd ("displaced", class_maintenance, &debug_displaced, _("\
4757 Set displaced stepping debugging."), _("\
4758 Show displaced stepping debugging."), _("\
4759 When non-zero, displaced stepping specific debugging is enabled."),
4761 show_debug_displaced,
4762 &setdebuglist, &showdebuglist);
4764 add_setshow_boolean_cmd ("non-stop", no_class,
4766 Set whether gdb controls the inferior in non-stop mode."), _("\
4767 Show whether gdb controls the inferior in non-stop mode."), _("\
4768 When debugging a multi-threaded program and this setting is\n\
4769 off (the default, also called all-stop mode), when one thread stops\n\
4770 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
4771 all other threads in the program while you interact with the thread of\n\
4772 interest. When you continue or step a thread, you can allow the other\n\
4773 threads to run, or have them remain stopped, but while you inspect any\n\
4774 thread's state, all threads stop.\n\
4776 In non-stop mode, when one thread stops, other threads can continue\n\
4777 to run freely. You'll be able to step each thread independently,\n\
4778 leave it stopped or free to run as needed."),
4784 numsigs = (int) TARGET_SIGNAL_LAST;
4785 signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
4786 signal_print = (unsigned char *)
4787 xmalloc (sizeof (signal_print[0]) * numsigs);
4788 signal_program = (unsigned char *)
4789 xmalloc (sizeof (signal_program[0]) * numsigs);
4790 for (i = 0; i < numsigs; i++)
4793 signal_print[i] = 1;
4794 signal_program[i] = 1;
4797 /* Signals caused by debugger's own actions
4798 should not be given to the program afterwards. */
4799 signal_program[TARGET_SIGNAL_TRAP] = 0;
4800 signal_program[TARGET_SIGNAL_INT] = 0;
4802 /* Signals that are not errors should not normally enter the debugger. */
4803 signal_stop[TARGET_SIGNAL_ALRM] = 0;
4804 signal_print[TARGET_SIGNAL_ALRM] = 0;
4805 signal_stop[TARGET_SIGNAL_VTALRM] = 0;
4806 signal_print[TARGET_SIGNAL_VTALRM] = 0;
4807 signal_stop[TARGET_SIGNAL_PROF] = 0;
4808 signal_print[TARGET_SIGNAL_PROF] = 0;
4809 signal_stop[TARGET_SIGNAL_CHLD] = 0;
4810 signal_print[TARGET_SIGNAL_CHLD] = 0;
4811 signal_stop[TARGET_SIGNAL_IO] = 0;
4812 signal_print[TARGET_SIGNAL_IO] = 0;
4813 signal_stop[TARGET_SIGNAL_POLL] = 0;
4814 signal_print[TARGET_SIGNAL_POLL] = 0;
4815 signal_stop[TARGET_SIGNAL_URG] = 0;
4816 signal_print[TARGET_SIGNAL_URG] = 0;
4817 signal_stop[TARGET_SIGNAL_WINCH] = 0;
4818 signal_print[TARGET_SIGNAL_WINCH] = 0;
4820 /* These signals are used internally by user-level thread
4821 implementations. (See signal(5) on Solaris.) Like the above
4822 signals, a healthy program receives and handles them as part of
4823 its normal operation. */
4824 signal_stop[TARGET_SIGNAL_LWP] = 0;
4825 signal_print[TARGET_SIGNAL_LWP] = 0;
4826 signal_stop[TARGET_SIGNAL_WAITING] = 0;
4827 signal_print[TARGET_SIGNAL_WAITING] = 0;
4828 signal_stop[TARGET_SIGNAL_CANCEL] = 0;
4829 signal_print[TARGET_SIGNAL_CANCEL] = 0;
4831 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
4832 &stop_on_solib_events, _("\
4833 Set stopping for shared library events."), _("\
4834 Show stopping for shared library events."), _("\
4835 If nonzero, gdb will give control to the user when the dynamic linker\n\
4836 notifies gdb of shared library events. The most common event of interest\n\
4837 to the user would be loading/unloading of a new library."),
4839 show_stop_on_solib_events,
4840 &setlist, &showlist);
4842 add_setshow_enum_cmd ("follow-fork-mode", class_run,
4843 follow_fork_mode_kind_names,
4844 &follow_fork_mode_string, _("\
4845 Set debugger response to a program call of fork or vfork."), _("\
4846 Show debugger response to a program call of fork or vfork."), _("\
4847 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4848 parent - the original process is debugged after a fork\n\
4849 child - the new process is debugged after a fork\n\
4850 The unfollowed process will continue to run.\n\
4851 By default, the debugger will follow the parent process."),
4853 show_follow_fork_mode_string,
4854 &setlist, &showlist);
4856 add_setshow_enum_cmd ("scheduler-locking", class_run,
4857 scheduler_enums, &scheduler_mode, _("\
4858 Set mode for locking scheduler during execution."), _("\
4859 Show mode for locking scheduler during execution."), _("\
4860 off == no locking (threads may preempt at any time)\n\
4861 on == full locking (no thread except the current thread may run)\n\
4862 step == scheduler locked during every single-step operation.\n\
4863 In this mode, no other thread may run during a step command.\n\
4864 Other threads may run while stepping over a function call ('next')."),
4865 set_schedlock_func, /* traps on target vector */
4866 show_scheduler_mode,
4867 &setlist, &showlist);
4869 add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
4870 Set mode of the step operation."), _("\
4871 Show mode of the step operation."), _("\
4872 When set, doing a step over a function without debug line information\n\
4873 will stop at the first instruction of that function. Otherwise, the\n\
4874 function is skipped and the step command stops at a different source line."),
4876 show_step_stop_if_no_debug,
4877 &setlist, &showlist);
4879 add_setshow_boolean_cmd ("can-use-displaced-stepping", class_maintenance,
4880 &can_use_displaced_stepping, _("\
4881 Set debugger's willingness to use displaced stepping."), _("\
4882 Show debugger's willingness to use displaced stepping."), _("\
4883 If zero, gdb will not use displaced stepping to step over\n\
4884 breakpoints, even if such is supported by the target."),
4886 show_can_use_displaced_stepping,
4887 &maintenance_set_cmdlist,
4888 &maintenance_show_cmdlist);
4890 /* ptid initializations */
4891 null_ptid = ptid_build (0, 0, 0);
4892 minus_one_ptid = ptid_build (-1, 0, 0);
4893 inferior_ptid = null_ptid;
4894 target_last_wait_ptid = minus_one_ptid;
4895 displaced_step_ptid = null_ptid;
4897 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);