1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
5 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002 Free Software
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 2 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, write to the Free Software
22 Foundation, Inc., 59 Temple Place - Suite 330,
23 Boston, MA 02111-1307, USA. */
26 #include "gdb_string.h"
31 #include "breakpoint.h"
35 #include "cli/cli-script.h"
37 #include "gdbthread.h"
46 /* Prototypes for local functions */
48 static void signals_info (char *, int);
50 static void handle_command (char *, int);
52 static void sig_print_info (enum target_signal);
54 static void sig_print_header (void);
56 static void resume_cleanups (void *);
58 static int hook_stop_stub (void *);
60 static void delete_breakpoint_current_contents (void *);
62 static void set_follow_fork_mode_command (char *arg, int from_tty,
63 struct cmd_list_element *c);
65 static int restore_selected_frame (void *);
67 static void build_infrun (void);
69 static void follow_inferior_fork (int parent_pid, int child_pid,
70 int has_forked, int has_vforked);
72 static void follow_fork (int parent_pid, int child_pid);
74 static void follow_vfork (int parent_pid, int child_pid);
76 static void set_schedlock_func (char *args, int from_tty,
77 struct cmd_list_element *c);
79 struct execution_control_state;
81 static int currently_stepping (struct execution_control_state *ecs);
83 static void xdb_handle_command (char *args, int from_tty);
85 void _initialize_infrun (void);
87 int inferior_ignoring_startup_exec_events = 0;
88 int inferior_ignoring_leading_exec_events = 0;
90 /* When set, stop the 'step' command if we enter a function which has
91 no line number information. The normal behavior is that we step
92 over such function. */
93 int step_stop_if_no_debug = 0;
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 /* This is true for configurations that may follow through execl() and
106 similar functions. At present this is only true for HP-UX native. */
108 #ifndef MAY_FOLLOW_EXEC
109 #define MAY_FOLLOW_EXEC (0)
112 static int may_follow_exec = MAY_FOLLOW_EXEC;
114 /* Dynamic function trampolines are similar to solib trampolines in that they
115 are between the caller and the callee. The difference is that when you
116 enter a dynamic trampoline, you can't determine the callee's address. Some
117 (usually complex) code needs to run in the dynamic trampoline to figure out
118 the callee's address. This macro is usually called twice. First, when we
119 enter the trampoline (looks like a normal function call at that point). It
120 should return the PC of a point within the trampoline where the callee's
121 address is known. Second, when we hit the breakpoint, this routine returns
122 the callee's address. At that point, things proceed as per a step resume
125 #ifndef DYNAMIC_TRAMPOLINE_NEXTPC
126 #define DYNAMIC_TRAMPOLINE_NEXTPC(pc) 0
129 /* If the program uses ELF-style shared libraries, then calls to
130 functions in shared libraries go through stubs, which live in a
131 table called the PLT (Procedure Linkage Table). The first time the
132 function is called, the stub sends control to the dynamic linker,
133 which looks up the function's real address, patches the stub so
134 that future calls will go directly to the function, and then passes
135 control to the function.
137 If we are stepping at the source level, we don't want to see any of
138 this --- we just want to skip over the stub and the dynamic linker.
139 The simple approach is to single-step until control leaves the
142 However, on some systems (e.g., Red Hat's 5.2 distribution) the
143 dynamic linker calls functions in the shared C library, so you
144 can't tell from the PC alone whether the dynamic linker is still
145 running. In this case, we use a step-resume breakpoint to get us
146 past the dynamic linker, as if we were using "next" to step over a
149 IN_SOLIB_DYNSYM_RESOLVE_CODE says whether we're in the dynamic
150 linker code or not. Normally, this means we single-step. However,
151 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
152 address where we can place a step-resume breakpoint to get past the
153 linker's symbol resolution function.
155 IN_SOLIB_DYNSYM_RESOLVE_CODE can generally be implemented in a
156 pretty portable way, by comparing the PC against the address ranges
157 of the dynamic linker's sections.
159 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
160 it depends on internal details of the dynamic linker. It's usually
161 not too hard to figure out where to put a breakpoint, but it
162 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
163 sanity checking. If it can't figure things out, returning zero and
164 getting the (possibly confusing) stepping behavior is better than
165 signalling an error, which will obscure the change in the
168 #ifndef IN_SOLIB_DYNSYM_RESOLVE_CODE
169 #define IN_SOLIB_DYNSYM_RESOLVE_CODE(pc) 0
172 #ifndef SKIP_SOLIB_RESOLVER
173 #define SKIP_SOLIB_RESOLVER(pc) 0
176 /* This function returns TRUE if pc is the address of an instruction
177 that lies within the dynamic linker (such as the event hook, or the
180 This function must be used only when a dynamic linker event has
181 been caught, and the inferior is being stepped out of the hook, or
182 undefined results are guaranteed. */
184 #ifndef SOLIB_IN_DYNAMIC_LINKER
185 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
188 /* On MIPS16, a function that returns a floating point value may call
189 a library helper function to copy the return value to a floating point
190 register. The IGNORE_HELPER_CALL macro returns non-zero if we
191 should ignore (i.e. step over) this function call. */
192 #ifndef IGNORE_HELPER_CALL
193 #define IGNORE_HELPER_CALL(pc) 0
196 /* On some systems, the PC may be left pointing at an instruction that won't
197 actually be executed. This is usually indicated by a bit in the PSW. If
198 we find ourselves in such a state, then we step the target beyond the
199 nullified instruction before returning control to the user so as to avoid
202 #ifndef INSTRUCTION_NULLIFIED
203 #define INSTRUCTION_NULLIFIED 0
206 /* We can't step off a permanent breakpoint in the ordinary way, because we
207 can't remove it. Instead, we have to advance the PC to the next
208 instruction. This macro should expand to a pointer to a function that
209 does that, or zero if we have no such function. If we don't have a
210 definition for it, we have to report an error. */
211 #ifndef SKIP_PERMANENT_BREAKPOINT
212 #define SKIP_PERMANENT_BREAKPOINT (default_skip_permanent_breakpoint)
214 default_skip_permanent_breakpoint (void)
217 The program is stopped at a permanent breakpoint, but GDB does not know\n\
218 how to step past a permanent breakpoint on this architecture. Try using\n\
219 a command like `return' or `jump' to continue execution.");
224 /* Convert the #defines into values. This is temporary until wfi control
225 flow is completely sorted out. */
227 #ifndef HAVE_STEPPABLE_WATCHPOINT
228 #define HAVE_STEPPABLE_WATCHPOINT 0
230 #undef HAVE_STEPPABLE_WATCHPOINT
231 #define HAVE_STEPPABLE_WATCHPOINT 1
234 #ifndef HAVE_NONSTEPPABLE_WATCHPOINT
235 #define HAVE_NONSTEPPABLE_WATCHPOINT 0
237 #undef HAVE_NONSTEPPABLE_WATCHPOINT
238 #define HAVE_NONSTEPPABLE_WATCHPOINT 1
241 #ifndef HAVE_CONTINUABLE_WATCHPOINT
242 #define HAVE_CONTINUABLE_WATCHPOINT 0
244 #undef HAVE_CONTINUABLE_WATCHPOINT
245 #define HAVE_CONTINUABLE_WATCHPOINT 1
248 #ifndef CANNOT_STEP_HW_WATCHPOINTS
249 #define CANNOT_STEP_HW_WATCHPOINTS 0
251 #undef CANNOT_STEP_HW_WATCHPOINTS
252 #define CANNOT_STEP_HW_WATCHPOINTS 1
255 /* Tables of how to react to signals; the user sets them. */
257 static unsigned char *signal_stop;
258 static unsigned char *signal_print;
259 static unsigned char *signal_program;
261 #define SET_SIGS(nsigs,sigs,flags) \
263 int signum = (nsigs); \
264 while (signum-- > 0) \
265 if ((sigs)[signum]) \
266 (flags)[signum] = 1; \
269 #define UNSET_SIGS(nsigs,sigs,flags) \
271 int signum = (nsigs); \
272 while (signum-- > 0) \
273 if ((sigs)[signum]) \
274 (flags)[signum] = 0; \
277 /* Value to pass to target_resume() to cause all threads to resume */
279 #define RESUME_ALL (pid_to_ptid (-1))
281 /* Command list pointer for the "stop" placeholder. */
283 static struct cmd_list_element *stop_command;
285 /* Nonzero if breakpoints are now inserted in the inferior. */
287 static int breakpoints_inserted;
289 /* Function inferior was in as of last step command. */
291 static struct symbol *step_start_function;
293 /* Nonzero if we are expecting a trace trap and should proceed from it. */
295 static int trap_expected;
298 /* Nonzero if we want to give control to the user when we're notified
299 of shared library events by the dynamic linker. */
300 static int stop_on_solib_events;
304 /* Nonzero if the next time we try to continue the inferior, it will
305 step one instruction and generate a spurious trace trap.
306 This is used to compensate for a bug in HP-UX. */
308 static int trap_expected_after_continue;
311 /* Nonzero means expecting a trace trap
312 and should stop the inferior and return silently when it happens. */
316 /* Nonzero means expecting a trap and caller will handle it themselves.
317 It is used after attach, due to attaching to a process;
318 when running in the shell before the child program has been exec'd;
319 and when running some kinds of remote stuff (FIXME?). */
321 int stop_soon_quietly;
323 /* Nonzero if proceed is being used for a "finish" command or a similar
324 situation when stop_registers should be saved. */
326 int proceed_to_finish;
328 /* Save register contents here when about to pop a stack dummy frame,
329 if-and-only-if proceed_to_finish is set.
330 Thus this contains the return value from the called function (assuming
331 values are returned in a register). */
333 struct regcache *stop_registers;
335 /* Nonzero if program stopped due to error trying to insert breakpoints. */
337 static int breakpoints_failed;
339 /* Nonzero after stop if current stack frame should be printed. */
341 static int stop_print_frame;
343 static struct breakpoint *step_resume_breakpoint = NULL;
344 static struct breakpoint *through_sigtramp_breakpoint = NULL;
346 /* On some platforms (e.g., HP-UX), hardware watchpoints have bad
347 interactions with an inferior that is running a kernel function
348 (aka, a system call or "syscall"). wait_for_inferior therefore
349 may have a need to know when the inferior is in a syscall. This
350 is a count of the number of inferior threads which are known to
351 currently be running in a syscall. */
352 static int number_of_threads_in_syscalls;
354 /* This is a cached copy of the pid/waitstatus of the last event
355 returned by target_wait()/target_wait_hook(). This information is
356 returned by get_last_target_status(). */
357 static ptid_t target_last_wait_ptid;
358 static struct target_waitstatus target_last_waitstatus;
360 /* This is used to remember when a fork, vfork or exec event
361 was caught by a catchpoint, and thus the event is to be
362 followed at the next resume of the inferior, and not
366 enum target_waitkind kind;
376 char *execd_pathname;
380 /* Some platforms don't allow us to do anything meaningful with a
381 vforked child until it has exec'd. Vforked processes on such
382 platforms can only be followed after they've exec'd.
384 When this is set to 0, a vfork can be immediately followed,
385 and an exec can be followed merely as an exec. When this is
386 set to 1, a vfork event has been seen, but cannot be followed
387 until the exec is seen.
389 (In the latter case, inferior_ptid is still the parent of the
390 vfork, and pending_follow.fork_event.child_pid is the child. The
391 appropriate process is followed, according to the setting of
392 follow-fork-mode.) */
393 static int follow_vfork_when_exec;
395 static const char follow_fork_mode_ask[] = "ask";
396 static const char follow_fork_mode_both[] = "both";
397 static const char follow_fork_mode_child[] = "child";
398 static const char follow_fork_mode_parent[] = "parent";
400 static const char *follow_fork_mode_kind_names[] = {
401 follow_fork_mode_ask,
402 /* ??rehrauer: The "both" option is broken, by what may be a 10.20
403 kernel problem. It's also not terribly useful without a GUI to
404 help the user drive two debuggers. So for now, I'm disabling the
406 /* follow_fork_mode_both, */
407 follow_fork_mode_child,
408 follow_fork_mode_parent,
412 static const char *follow_fork_mode_string = follow_fork_mode_parent;
416 follow_inferior_fork (int parent_pid, int child_pid, int has_forked,
419 int followed_parent = 0;
420 int followed_child = 0;
422 /* Which process did the user want us to follow? */
423 const char *follow_mode = follow_fork_mode_string;
425 /* Or, did the user not know, and want us to ask? */
426 if (follow_fork_mode_string == follow_fork_mode_ask)
428 internal_error (__FILE__, __LINE__,
429 "follow_inferior_fork: \"ask\" mode not implemented");
430 /* follow_mode = follow_fork_mode_...; */
433 /* If we're to be following the parent, then detach from child_pid.
434 We're already following the parent, so need do nothing explicit
436 if (follow_mode == follow_fork_mode_parent)
440 /* We're already attached to the parent, by default. */
442 /* Before detaching from the child, remove all breakpoints from
443 it. (This won't actually modify the breakpoint list, but will
444 physically remove the breakpoints from the child.) */
445 if (!has_vforked || !follow_vfork_when_exec)
447 detach_breakpoints (child_pid);
448 #ifdef SOLIB_REMOVE_INFERIOR_HOOK
449 SOLIB_REMOVE_INFERIOR_HOOK (child_pid);
453 /* Detach from the child. */
456 target_require_detach (child_pid, "", 1);
459 /* If we're to be following the child, then attach to it, detach
460 from inferior_ptid, and set inferior_ptid to child_pid. */
461 else if (follow_mode == follow_fork_mode_child)
463 char child_pid_spelling[100]; /* Arbitrary length. */
467 /* Before detaching from the parent, detach all breakpoints from
468 the child. But only if we're forking, or if we follow vforks
469 as soon as they happen. (If we're following vforks only when
470 the child has exec'd, then it's very wrong to try to write
471 back the "shadow contents" of inserted breakpoints now -- they
472 belong to the child's pre-exec'd a.out.) */
473 if (!has_vforked || !follow_vfork_when_exec)
475 detach_breakpoints (child_pid);
478 /* Before detaching from the parent, remove all breakpoints from it. */
479 remove_breakpoints ();
481 /* Also reset the solib inferior hook from the parent. */
482 #ifdef SOLIB_REMOVE_INFERIOR_HOOK
483 SOLIB_REMOVE_INFERIOR_HOOK (PIDGET (inferior_ptid));
486 /* Detach from the parent. */
488 target_detach (NULL, 1);
490 /* Attach to the child. */
491 inferior_ptid = pid_to_ptid (child_pid);
492 sprintf (child_pid_spelling, "%d", child_pid);
495 target_require_attach (child_pid_spelling, 1);
497 /* Was there a step_resume breakpoint? (There was if the user
498 did a "next" at the fork() call.) If so, explicitly reset its
501 step_resumes are a form of bp that are made to be per-thread.
502 Since we created the step_resume bp when the parent process
503 was being debugged, and now are switching to the child process,
504 from the breakpoint package's viewpoint, that's a switch of
505 "threads". We must update the bp's notion of which thread
506 it is for, or it'll be ignored when it triggers... */
507 if (step_resume_breakpoint && (!has_vforked || !follow_vfork_when_exec))
508 breakpoint_re_set_thread (step_resume_breakpoint);
510 /* Reinsert all breakpoints in the child. (The user may've set
511 breakpoints after catching the fork, in which case those
512 actually didn't get set in the child, but only in the parent.) */
513 if (!has_vforked || !follow_vfork_when_exec)
515 breakpoint_re_set ();
516 insert_breakpoints ();
520 /* If we're to be following both parent and child, then fork ourselves,
521 and attach the debugger clone to the child. */
522 else if (follow_mode == follow_fork_mode_both)
524 char pid_suffix[100]; /* Arbitrary length. */
526 /* Clone ourselves to follow the child. This is the end of our
527 involvement with child_pid; our clone will take it from here... */
529 target_clone_and_follow_inferior (child_pid, &followed_child);
530 followed_parent = !followed_child;
532 /* We continue to follow the parent. To help distinguish the two
533 debuggers, though, both we and our clone will reset our prompts. */
534 sprintf (pid_suffix, "[%d] ", PIDGET (inferior_ptid));
535 set_prompt (strcat (get_prompt (), pid_suffix));
538 /* The parent and child of a vfork share the same address space.
539 Also, on some targets the order in which vfork and exec events
540 are received for parent in child requires some delicate handling
543 For instance, on ptrace-based HPUX we receive the child's vfork
544 event first, at which time the parent has been suspended by the
545 OS and is essentially untouchable until the child's exit or second
546 exec event arrives. At that time, the parent's vfork event is
547 delivered to us, and that's when we see and decide how to follow
548 the vfork. But to get to that point, we must continue the child
549 until it execs or exits. To do that smoothly, all breakpoints
550 must be removed from the child, in case there are any set between
551 the vfork() and exec() calls. But removing them from the child
552 also removes them from the parent, due to the shared-address-space
553 nature of a vfork'd parent and child. On HPUX, therefore, we must
554 take care to restore the bp's to the parent before we continue it.
555 Else, it's likely that we may not stop in the expected place. (The
556 worst scenario is when the user tries to step over a vfork() call;
557 the step-resume bp must be restored for the step to properly stop
558 in the parent after the call completes!)
560 Sequence of events, as reported to gdb from HPUX:
562 Parent Child Action for gdb to take
563 -------------------------------------------------------
564 1 VFORK Continue child
570 target_post_follow_vfork (parent_pid,
571 followed_parent, child_pid, followed_child);
574 pending_follow.fork_event.saw_parent_fork = 0;
575 pending_follow.fork_event.saw_child_fork = 0;
579 follow_fork (int parent_pid, int child_pid)
581 follow_inferior_fork (parent_pid, child_pid, 1, 0);
585 /* Forward declaration. */
586 static void follow_exec (int, char *);
589 follow_vfork (int parent_pid, int child_pid)
591 follow_inferior_fork (parent_pid, child_pid, 0, 1);
593 /* Did we follow the child? Had it exec'd before we saw the parent vfork? */
594 if (pending_follow.fork_event.saw_child_exec
595 && (PIDGET (inferior_ptid) == child_pid))
597 pending_follow.fork_event.saw_child_exec = 0;
598 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
599 follow_exec (PIDGET (inferior_ptid), pending_follow.execd_pathname);
600 xfree (pending_follow.execd_pathname);
604 /* EXECD_PATHNAME is assumed to be non-NULL. */
607 follow_exec (int pid, char *execd_pathname)
610 struct target_ops *tgt;
612 if (!may_follow_exec)
615 /* Did this exec() follow a vfork()? If so, we must follow the
616 vfork now too. Do it before following the exec. */
617 if (follow_vfork_when_exec &&
618 (pending_follow.kind == TARGET_WAITKIND_VFORKED))
620 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
621 follow_vfork (PIDGET (inferior_ptid),
622 pending_follow.fork_event.child_pid);
623 follow_vfork_when_exec = 0;
624 saved_pid = PIDGET (inferior_ptid);
626 /* Did we follow the parent? If so, we're done. If we followed
627 the child then we must also follow its exec(). */
628 if (PIDGET (inferior_ptid) == pending_follow.fork_event.parent_pid)
632 /* This is an exec event that we actually wish to pay attention to.
633 Refresh our symbol table to the newly exec'd program, remove any
636 If there are breakpoints, they aren't really inserted now,
637 since the exec() transformed our inferior into a fresh set
640 We want to preserve symbolic breakpoints on the list, since
641 we have hopes that they can be reset after the new a.out's
642 symbol table is read.
644 However, any "raw" breakpoints must be removed from the list
645 (e.g., the solib bp's), since their address is probably invalid
648 And, we DON'T want to call delete_breakpoints() here, since
649 that may write the bp's "shadow contents" (the instruction
650 value that was overwritten witha TRAP instruction). Since
651 we now have a new a.out, those shadow contents aren't valid. */
652 update_breakpoints_after_exec ();
654 /* If there was one, it's gone now. We cannot truly step-to-next
655 statement through an exec(). */
656 step_resume_breakpoint = NULL;
657 step_range_start = 0;
660 /* If there was one, it's gone now. */
661 through_sigtramp_breakpoint = NULL;
663 /* What is this a.out's name? */
664 printf_unfiltered ("Executing new program: %s\n", execd_pathname);
666 /* We've followed the inferior through an exec. Therefore, the
667 inferior has essentially been killed & reborn. */
669 /* First collect the run target in effect. */
670 tgt = find_run_target ();
671 /* If we can't find one, things are in a very strange state... */
673 error ("Could find run target to save before following exec");
675 gdb_flush (gdb_stdout);
676 target_mourn_inferior ();
677 inferior_ptid = pid_to_ptid (saved_pid);
678 /* Because mourn_inferior resets inferior_ptid. */
681 /* That a.out is now the one to use. */
682 exec_file_attach (execd_pathname, 0);
684 /* And also is where symbols can be found. */
685 symbol_file_add_main (execd_pathname, 0);
687 /* Reset the shared library package. This ensures that we get
688 a shlib event when the child reaches "_start", at which point
689 the dld will have had a chance to initialize the child. */
690 #if defined(SOLIB_RESTART)
693 #ifdef SOLIB_CREATE_INFERIOR_HOOK
694 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
697 /* Reinsert all breakpoints. (Those which were symbolic have
698 been reset to the proper address in the new a.out, thanks
699 to symbol_file_command...) */
700 insert_breakpoints ();
702 /* The next resume of this inferior should bring it to the shlib
703 startup breakpoints. (If the user had also set bp's on
704 "main" from the old (parent) process, then they'll auto-
705 matically get reset there in the new process.) */
708 /* Non-zero if we just simulating a single-step. This is needed
709 because we cannot remove the breakpoints in the inferior process
710 until after the `wait' in `wait_for_inferior'. */
711 static int singlestep_breakpoints_inserted_p = 0;
714 /* Things to clean up if we QUIT out of resume (). */
717 resume_cleanups (void *ignore)
722 static const char schedlock_off[] = "off";
723 static const char schedlock_on[] = "on";
724 static const char schedlock_step[] = "step";
725 static const char *scheduler_mode = schedlock_off;
726 static const char *scheduler_enums[] = {
734 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
736 /* NOTE: cagney/2002-03-17: The add_show_from_set() function clones
737 the set command passed as a parameter. The clone operation will
738 include (BUG?) any ``set'' command callback, if present.
739 Commands like ``info set'' call all the ``show'' command
740 callbacks. Unfortunatly, for ``show'' commands cloned from
741 ``set'', this includes callbacks belonging to ``set'' commands.
742 Making this worse, this only occures if add_show_from_set() is
743 called after add_cmd_sfunc() (BUG?). */
744 if (cmd_type (c) == set_cmd)
745 if (!target_can_lock_scheduler)
747 scheduler_mode = schedlock_off;
748 error ("Target '%s' cannot support this command.", target_shortname);
753 /* Resume the inferior, but allow a QUIT. This is useful if the user
754 wants to interrupt some lengthy single-stepping operation
755 (for child processes, the SIGINT goes to the inferior, and so
756 we get a SIGINT random_signal, but for remote debugging and perhaps
757 other targets, that's not true).
759 STEP nonzero if we should step (zero to continue instead).
760 SIG is the signal to give the inferior (zero for none). */
762 resume (int step, enum target_signal sig)
764 int should_resume = 1;
765 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
768 /* FIXME: calling breakpoint_here_p (read_pc ()) three times! */
771 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
772 over an instruction that causes a page fault without triggering
773 a hardware watchpoint. The kernel properly notices that it shouldn't
774 stop, because the hardware watchpoint is not triggered, but it forgets
775 the step request and continues the program normally.
776 Work around the problem by removing hardware watchpoints if a step is
777 requested, GDB will check for a hardware watchpoint trigger after the
779 if (CANNOT_STEP_HW_WATCHPOINTS && step && breakpoints_inserted)
780 remove_hw_watchpoints ();
783 /* Normally, by the time we reach `resume', the breakpoints are either
784 removed or inserted, as appropriate. The exception is if we're sitting
785 at a permanent breakpoint; we need to step over it, but permanent
786 breakpoints can't be removed. So we have to test for it here. */
787 if (breakpoint_here_p (read_pc ()) == permanent_breakpoint_here)
788 SKIP_PERMANENT_BREAKPOINT ();
790 if (SOFTWARE_SINGLE_STEP_P () && step)
792 /* Do it the hard way, w/temp breakpoints */
793 SOFTWARE_SINGLE_STEP (sig, 1 /*insert-breakpoints */ );
794 /* ...and don't ask hardware to do it. */
796 /* and do not pull these breakpoints until after a `wait' in
797 `wait_for_inferior' */
798 singlestep_breakpoints_inserted_p = 1;
801 /* Handle any optimized stores to the inferior NOW... */
802 #ifdef DO_DEFERRED_STORES
806 /* If there were any forks/vforks/execs that were caught and are
807 now to be followed, then do so. */
808 switch (pending_follow.kind)
810 case (TARGET_WAITKIND_FORKED):
811 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
812 follow_fork (PIDGET (inferior_ptid),
813 pending_follow.fork_event.child_pid);
816 case (TARGET_WAITKIND_VFORKED):
818 int saw_child_exec = pending_follow.fork_event.saw_child_exec;
820 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
821 follow_vfork (PIDGET (inferior_ptid),
822 pending_follow.fork_event.child_pid);
824 /* Did we follow the child, but not yet see the child's exec event?
825 If so, then it actually ought to be waiting for us; we respond to
826 parent vfork events. We don't actually want to resume the child
827 in this situation; we want to just get its exec event. */
828 if (!saw_child_exec &&
829 (PIDGET (inferior_ptid) == pending_follow.fork_event.child_pid))
834 case (TARGET_WAITKIND_EXECD):
835 /* If we saw a vfork event but couldn't follow it until we saw
836 an exec, then now might be the time! */
837 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
838 /* follow_exec is called as soon as the exec event is seen. */
845 /* Install inferior's terminal modes. */
846 target_terminal_inferior ();
852 resume_ptid = RESUME_ALL; /* Default */
854 if ((step || singlestep_breakpoints_inserted_p) &&
855 !breakpoints_inserted && breakpoint_here_p (read_pc ()))
857 /* Stepping past a breakpoint without inserting breakpoints.
858 Make sure only the current thread gets to step, so that
859 other threads don't sneak past breakpoints while they are
862 resume_ptid = inferior_ptid;
865 if ((scheduler_mode == schedlock_on) ||
866 (scheduler_mode == schedlock_step &&
867 (step || singlestep_breakpoints_inserted_p)))
869 /* User-settable 'scheduler' mode requires solo thread resume. */
870 resume_ptid = inferior_ptid;
873 #ifdef CANNOT_STEP_BREAKPOINT
874 /* Most targets can step a breakpoint instruction, thus executing it
875 normally. But if this one cannot, just continue and we will hit
877 if (step && breakpoints_inserted && breakpoint_here_p (read_pc ()))
880 target_resume (resume_ptid, step, sig);
883 discard_cleanups (old_cleanups);
887 /* Clear out all variables saying what to do when inferior is continued.
888 First do this, then set the ones you want, then call `proceed'. */
891 clear_proceed_status (void)
894 step_range_start = 0;
896 step_frame_address = 0;
897 step_over_calls = STEP_OVER_UNDEBUGGABLE;
899 stop_soon_quietly = 0;
900 proceed_to_finish = 0;
901 breakpoint_proceeded = 1; /* We're about to proceed... */
903 /* Discard any remaining commands or status from previous stop. */
904 bpstat_clear (&stop_bpstat);
907 /* Basic routine for continuing the program in various fashions.
909 ADDR is the address to resume at, or -1 for resume where stopped.
910 SIGGNAL is the signal to give it, or 0 for none,
911 or -1 for act according to how it stopped.
912 STEP is nonzero if should trap after one instruction.
913 -1 means return after that and print nothing.
914 You should probably set various step_... variables
915 before calling here, if you are stepping.
917 You should call clear_proceed_status before calling proceed. */
920 proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
925 step_start_function = find_pc_function (read_pc ());
929 if (addr == (CORE_ADDR) -1)
931 /* If there is a breakpoint at the address we will resume at,
932 step one instruction before inserting breakpoints
933 so that we do not stop right away (and report a second
934 hit at this breakpoint). */
936 if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
939 #ifndef STEP_SKIPS_DELAY
940 #define STEP_SKIPS_DELAY(pc) (0)
941 #define STEP_SKIPS_DELAY_P (0)
943 /* Check breakpoint_here_p first, because breakpoint_here_p is fast
944 (it just checks internal GDB data structures) and STEP_SKIPS_DELAY
945 is slow (it needs to read memory from the target). */
946 if (STEP_SKIPS_DELAY_P
947 && breakpoint_here_p (read_pc () + 4)
948 && STEP_SKIPS_DELAY (read_pc ()))
956 #ifdef PREPARE_TO_PROCEED
957 /* In a multi-threaded task we may select another thread
958 and then continue or step.
960 But if the old thread was stopped at a breakpoint, it
961 will immediately cause another breakpoint stop without
962 any execution (i.e. it will report a breakpoint hit
963 incorrectly). So we must step over it first.
965 PREPARE_TO_PROCEED checks the current thread against the thread
966 that reported the most recent event. If a step-over is required
967 it returns TRUE and sets the current thread to the old thread. */
968 if (PREPARE_TO_PROCEED (1) && breakpoint_here_p (read_pc ()))
973 #endif /* PREPARE_TO_PROCEED */
976 if (trap_expected_after_continue)
978 /* If (step == 0), a trap will be automatically generated after
979 the first instruction is executed. Force step one
980 instruction to clear this condition. This should not occur
981 if step is nonzero, but it is harmless in that case. */
983 trap_expected_after_continue = 0;
985 #endif /* HP_OS_BUG */
988 /* We will get a trace trap after one instruction.
989 Continue it automatically and insert breakpoints then. */
993 insert_breakpoints ();
994 /* If we get here there was no call to error() in
995 insert breakpoints -- so they were inserted. */
996 breakpoints_inserted = 1;
999 if (siggnal != TARGET_SIGNAL_DEFAULT)
1000 stop_signal = siggnal;
1001 /* If this signal should not be seen by program,
1002 give it zero. Used for debugging signals. */
1003 else if (!signal_program[stop_signal])
1004 stop_signal = TARGET_SIGNAL_0;
1006 annotate_starting ();
1008 /* Make sure that output from GDB appears before output from the
1010 gdb_flush (gdb_stdout);
1012 /* Resume inferior. */
1013 resume (oneproc || step || bpstat_should_step (), stop_signal);
1015 /* Wait for it to stop (if not standalone)
1016 and in any case decode why it stopped, and act accordingly. */
1017 /* Do this only if we are not using the event loop, or if the target
1018 does not support asynchronous execution. */
1019 if (!event_loop_p || !target_can_async_p ())
1021 wait_for_inferior ();
1026 /* Record the pc and sp of the program the last time it stopped.
1027 These are just used internally by wait_for_inferior, but need
1028 to be preserved over calls to it and cleared when the inferior
1030 static CORE_ADDR prev_pc;
1031 static CORE_ADDR prev_func_start;
1032 static char *prev_func_name;
1035 /* Start remote-debugging of a machine over a serial link. */
1040 init_thread_list ();
1041 init_wait_for_inferior ();
1042 stop_soon_quietly = 1;
1045 /* Always go on waiting for the target, regardless of the mode. */
1046 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1047 indicate to wait_for_inferior that a target should timeout if
1048 nothing is returned (instead of just blocking). Because of this,
1049 targets expecting an immediate response need to, internally, set
1050 things up so that the target_wait() is forced to eventually
1052 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1053 differentiate to its caller what the state of the target is after
1054 the initial open has been performed. Here we're assuming that
1055 the target has stopped. It should be possible to eventually have
1056 target_open() return to the caller an indication that the target
1057 is currently running and GDB state should be set to the same as
1058 for an async run. */
1059 wait_for_inferior ();
1063 /* Initialize static vars when a new inferior begins. */
1066 init_wait_for_inferior (void)
1068 /* These are meaningless until the first time through wait_for_inferior. */
1070 prev_func_start = 0;
1071 prev_func_name = NULL;
1074 trap_expected_after_continue = 0;
1076 breakpoints_inserted = 0;
1077 breakpoint_init_inferior (inf_starting);
1079 /* Don't confuse first call to proceed(). */
1080 stop_signal = TARGET_SIGNAL_0;
1082 /* The first resume is not following a fork/vfork/exec. */
1083 pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
1084 pending_follow.fork_event.saw_parent_fork = 0;
1085 pending_follow.fork_event.saw_child_fork = 0;
1086 pending_follow.fork_event.saw_child_exec = 0;
1088 /* See wait_for_inferior's handling of SYSCALL_ENTRY/RETURN events. */
1089 number_of_threads_in_syscalls = 0;
1091 clear_proceed_status ();
1095 delete_breakpoint_current_contents (void *arg)
1097 struct breakpoint **breakpointp = (struct breakpoint **) arg;
1098 if (*breakpointp != NULL)
1100 delete_breakpoint (*breakpointp);
1101 *breakpointp = NULL;
1105 /* This enum encodes possible reasons for doing a target_wait, so that
1106 wfi can call target_wait in one place. (Ultimately the call will be
1107 moved out of the infinite loop entirely.) */
1111 infwait_normal_state,
1112 infwait_thread_hop_state,
1113 infwait_nullified_state,
1114 infwait_nonstep_watch_state
1117 /* Why did the inferior stop? Used to print the appropriate messages
1118 to the interface from within handle_inferior_event(). */
1119 enum inferior_stop_reason
1121 /* We don't know why. */
1123 /* Step, next, nexti, stepi finished. */
1125 /* Found breakpoint. */
1127 /* Inferior terminated by signal. */
1129 /* Inferior exited. */
1131 /* Inferior received signal, and user asked to be notified. */
1135 /* This structure contains what used to be local variables in
1136 wait_for_inferior. Probably many of them can return to being
1137 locals in handle_inferior_event. */
1139 struct execution_control_state
1141 struct target_waitstatus ws;
1142 struct target_waitstatus *wp;
1145 CORE_ADDR stop_func_start;
1146 CORE_ADDR stop_func_end;
1147 char *stop_func_name;
1148 struct symtab_and_line sal;
1149 int remove_breakpoints_on_following_step;
1151 struct symtab *current_symtab;
1152 int handling_longjmp; /* FIXME */
1154 ptid_t saved_inferior_ptid;
1156 int stepping_through_solib_after_catch;
1157 bpstat stepping_through_solib_catchpoints;
1158 int enable_hw_watchpoints_after_wait;
1159 int stepping_through_sigtramp;
1160 int new_thread_event;
1161 struct target_waitstatus tmpstatus;
1162 enum infwait_states infwait_state;
1167 void init_execution_control_state (struct execution_control_state *ecs);
1169 void handle_inferior_event (struct execution_control_state *ecs);
1171 static void check_sigtramp2 (struct execution_control_state *ecs);
1172 static void step_into_function (struct execution_control_state *ecs);
1173 static void step_over_function (struct execution_control_state *ecs);
1174 static void stop_stepping (struct execution_control_state *ecs);
1175 static void prepare_to_wait (struct execution_control_state *ecs);
1176 static void keep_going (struct execution_control_state *ecs);
1177 static void print_stop_reason (enum inferior_stop_reason stop_reason,
1180 /* Wait for control to return from inferior to debugger.
1181 If inferior gets a signal, we may decide to start it up again
1182 instead of returning. That is why there is a loop in this function.
1183 When this function actually returns it means the inferior
1184 should be left stopped and GDB should read more commands. */
1187 wait_for_inferior (void)
1189 struct cleanup *old_cleanups;
1190 struct execution_control_state ecss;
1191 struct execution_control_state *ecs;
1193 old_cleanups = make_cleanup (delete_step_resume_breakpoint,
1194 &step_resume_breakpoint);
1195 make_cleanup (delete_breakpoint_current_contents,
1196 &through_sigtramp_breakpoint);
1198 /* wfi still stays in a loop, so it's OK just to take the address of
1199 a local to get the ecs pointer. */
1202 /* Fill in with reasonable starting values. */
1203 init_execution_control_state (ecs);
1205 /* We'll update this if & when we switch to a new thread. */
1206 previous_inferior_ptid = inferior_ptid;
1208 overlay_cache_invalid = 1;
1210 /* We have to invalidate the registers BEFORE calling target_wait
1211 because they can be loaded from the target while in target_wait.
1212 This makes remote debugging a bit more efficient for those
1213 targets that provide critical registers as part of their normal
1214 status mechanism. */
1216 registers_changed ();
1220 if (target_wait_hook)
1221 ecs->ptid = target_wait_hook (ecs->waiton_ptid, ecs->wp);
1223 ecs->ptid = target_wait (ecs->waiton_ptid, ecs->wp);
1225 /* Now figure out what to do with the result of the result. */
1226 handle_inferior_event (ecs);
1228 if (!ecs->wait_some_more)
1231 do_cleanups (old_cleanups);
1234 /* Asynchronous version of wait_for_inferior. It is called by the
1235 event loop whenever a change of state is detected on the file
1236 descriptor corresponding to the target. It can be called more than
1237 once to complete a single execution command. In such cases we need
1238 to keep the state in a global variable ASYNC_ECSS. If it is the
1239 last time that this function is called for a single execution
1240 command, then report to the user that the inferior has stopped, and
1241 do the necessary cleanups. */
1243 struct execution_control_state async_ecss;
1244 struct execution_control_state *async_ecs;
1247 fetch_inferior_event (void *client_data)
1249 static struct cleanup *old_cleanups;
1251 async_ecs = &async_ecss;
1253 if (!async_ecs->wait_some_more)
1255 old_cleanups = make_exec_cleanup (delete_step_resume_breakpoint,
1256 &step_resume_breakpoint);
1257 make_exec_cleanup (delete_breakpoint_current_contents,
1258 &through_sigtramp_breakpoint);
1260 /* Fill in with reasonable starting values. */
1261 init_execution_control_state (async_ecs);
1263 /* We'll update this if & when we switch to a new thread. */
1264 previous_inferior_ptid = inferior_ptid;
1266 overlay_cache_invalid = 1;
1268 /* We have to invalidate the registers BEFORE calling target_wait
1269 because they can be loaded from the target while in target_wait.
1270 This makes remote debugging a bit more efficient for those
1271 targets that provide critical registers as part of their normal
1272 status mechanism. */
1274 registers_changed ();
1277 if (target_wait_hook)
1279 target_wait_hook (async_ecs->waiton_ptid, async_ecs->wp);
1281 async_ecs->ptid = target_wait (async_ecs->waiton_ptid, async_ecs->wp);
1283 /* Now figure out what to do with the result of the result. */
1284 handle_inferior_event (async_ecs);
1286 if (!async_ecs->wait_some_more)
1288 /* Do only the cleanups that have been added by this
1289 function. Let the continuations for the commands do the rest,
1290 if there are any. */
1291 do_exec_cleanups (old_cleanups);
1293 if (step_multi && stop_step)
1294 inferior_event_handler (INF_EXEC_CONTINUE, NULL);
1296 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
1300 /* Prepare an execution control state for looping through a
1301 wait_for_inferior-type loop. */
1304 init_execution_control_state (struct execution_control_state *ecs)
1306 /* ecs->another_trap? */
1307 ecs->random_signal = 0;
1308 ecs->remove_breakpoints_on_following_step = 0;
1309 ecs->handling_longjmp = 0; /* FIXME */
1310 ecs->update_step_sp = 0;
1311 ecs->stepping_through_solib_after_catch = 0;
1312 ecs->stepping_through_solib_catchpoints = NULL;
1313 ecs->enable_hw_watchpoints_after_wait = 0;
1314 ecs->stepping_through_sigtramp = 0;
1315 ecs->sal = find_pc_line (prev_pc, 0);
1316 ecs->current_line = ecs->sal.line;
1317 ecs->current_symtab = ecs->sal.symtab;
1318 ecs->infwait_state = infwait_normal_state;
1319 ecs->waiton_ptid = pid_to_ptid (-1);
1320 ecs->wp = &(ecs->ws);
1323 /* Call this function before setting step_resume_breakpoint, as a
1324 sanity check. There should never be more than one step-resume
1325 breakpoint per thread, so we should never be setting a new
1326 step_resume_breakpoint when one is already active. */
1328 check_for_old_step_resume_breakpoint (void)
1330 if (step_resume_breakpoint)
1332 ("GDB bug: infrun.c (wait_for_inferior): dropping old step_resume breakpoint");
1335 /* Return the cached copy of the last pid/waitstatus returned by
1336 target_wait()/target_wait_hook(). The data is actually cached by
1337 handle_inferior_event(), which gets called immediately after
1338 target_wait()/target_wait_hook(). */
1341 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
1343 *ptidp = target_last_wait_ptid;
1344 *status = target_last_waitstatus;
1347 /* Switch thread contexts, maintaining "infrun state". */
1350 context_switch (struct execution_control_state *ecs)
1352 /* Caution: it may happen that the new thread (or the old one!)
1353 is not in the thread list. In this case we must not attempt
1354 to "switch context", or we run the risk that our context may
1355 be lost. This may happen as a result of the target module
1356 mishandling thread creation. */
1358 if (in_thread_list (inferior_ptid) && in_thread_list (ecs->ptid))
1359 { /* Perform infrun state context switch: */
1360 /* Save infrun state for the old thread. */
1361 save_infrun_state (inferior_ptid, prev_pc,
1362 prev_func_start, prev_func_name,
1363 trap_expected, step_resume_breakpoint,
1364 through_sigtramp_breakpoint, step_range_start,
1365 step_range_end, step_frame_address,
1366 ecs->handling_longjmp, ecs->another_trap,
1367 ecs->stepping_through_solib_after_catch,
1368 ecs->stepping_through_solib_catchpoints,
1369 ecs->stepping_through_sigtramp,
1370 ecs->current_line, ecs->current_symtab, step_sp);
1372 /* Load infrun state for the new thread. */
1373 load_infrun_state (ecs->ptid, &prev_pc,
1374 &prev_func_start, &prev_func_name,
1375 &trap_expected, &step_resume_breakpoint,
1376 &through_sigtramp_breakpoint, &step_range_start,
1377 &step_range_end, &step_frame_address,
1378 &ecs->handling_longjmp, &ecs->another_trap,
1379 &ecs->stepping_through_solib_after_catch,
1380 &ecs->stepping_through_solib_catchpoints,
1381 &ecs->stepping_through_sigtramp,
1382 &ecs->current_line, &ecs->current_symtab, &step_sp);
1384 inferior_ptid = ecs->ptid;
1388 /* Given an execution control state that has been freshly filled in
1389 by an event from the inferior, figure out what it means and take
1390 appropriate action. */
1393 handle_inferior_event (struct execution_control_state *ecs)
1396 int stepped_after_stopped_by_watchpoint;
1397 int sw_single_step_trap_p = 0;
1399 /* Cache the last pid/waitstatus. */
1400 target_last_wait_ptid = ecs->ptid;
1401 target_last_waitstatus = *ecs->wp;
1403 switch (ecs->infwait_state)
1405 case infwait_thread_hop_state:
1406 /* Cancel the waiton_ptid. */
1407 ecs->waiton_ptid = pid_to_ptid (-1);
1408 /* Fall thru to the normal_state case. */
1410 case infwait_normal_state:
1411 /* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
1412 is serviced in this loop, below. */
1413 if (ecs->enable_hw_watchpoints_after_wait)
1415 TARGET_ENABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
1416 ecs->enable_hw_watchpoints_after_wait = 0;
1418 stepped_after_stopped_by_watchpoint = 0;
1421 case infwait_nullified_state:
1424 case infwait_nonstep_watch_state:
1425 insert_breakpoints ();
1427 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1428 handle things like signals arriving and other things happening
1429 in combination correctly? */
1430 stepped_after_stopped_by_watchpoint = 1;
1433 ecs->infwait_state = infwait_normal_state;
1435 flush_cached_frames ();
1437 /* If it's a new process, add it to the thread database */
1439 ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
1440 && !in_thread_list (ecs->ptid));
1442 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
1443 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
1445 add_thread (ecs->ptid);
1447 ui_out_text (uiout, "[New ");
1448 ui_out_text (uiout, target_pid_or_tid_to_str (ecs->ptid));
1449 ui_out_text (uiout, "]\n");
1452 /* NOTE: This block is ONLY meant to be invoked in case of a
1453 "thread creation event"! If it is invoked for any other
1454 sort of event (such as a new thread landing on a breakpoint),
1455 the event will be discarded, which is almost certainly
1458 To avoid this, the low-level module (eg. target_wait)
1459 should call in_thread_list and add_thread, so that the
1460 new thread is known by the time we get here. */
1462 /* We may want to consider not doing a resume here in order
1463 to give the user a chance to play with the new thread.
1464 It might be good to make that a user-settable option. */
1466 /* At this point, all threads are stopped (happens
1467 automatically in either the OS or the native code).
1468 Therefore we need to continue all threads in order to
1471 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
1472 prepare_to_wait (ecs);
1477 switch (ecs->ws.kind)
1479 case TARGET_WAITKIND_LOADED:
1480 /* Ignore gracefully during startup of the inferior, as it
1481 might be the shell which has just loaded some objects,
1482 otherwise add the symbols for the newly loaded objects. */
1484 if (!stop_soon_quietly)
1486 /* Remove breakpoints, SOLIB_ADD might adjust
1487 breakpoint addresses via breakpoint_re_set. */
1488 if (breakpoints_inserted)
1489 remove_breakpoints ();
1491 /* Check for any newly added shared libraries if we're
1492 supposed to be adding them automatically. Switch
1493 terminal for any messages produced by
1494 breakpoint_re_set. */
1495 target_terminal_ours_for_output ();
1496 SOLIB_ADD (NULL, 0, NULL, auto_solib_add);
1497 target_terminal_inferior ();
1499 /* Reinsert breakpoints and continue. */
1500 if (breakpoints_inserted)
1501 insert_breakpoints ();
1504 resume (0, TARGET_SIGNAL_0);
1505 prepare_to_wait (ecs);
1508 case TARGET_WAITKIND_SPURIOUS:
1509 resume (0, TARGET_SIGNAL_0);
1510 prepare_to_wait (ecs);
1513 case TARGET_WAITKIND_EXITED:
1514 target_terminal_ours (); /* Must do this before mourn anyway */
1515 print_stop_reason (EXITED, ecs->ws.value.integer);
1517 /* Record the exit code in the convenience variable $_exitcode, so
1518 that the user can inspect this again later. */
1519 set_internalvar (lookup_internalvar ("_exitcode"),
1520 value_from_longest (builtin_type_int,
1521 (LONGEST) ecs->ws.value.integer));
1522 gdb_flush (gdb_stdout);
1523 target_mourn_inferior ();
1524 singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
1525 stop_print_frame = 0;
1526 stop_stepping (ecs);
1529 case TARGET_WAITKIND_SIGNALLED:
1530 stop_print_frame = 0;
1531 stop_signal = ecs->ws.value.sig;
1532 target_terminal_ours (); /* Must do this before mourn anyway */
1534 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
1535 reach here unless the inferior is dead. However, for years
1536 target_kill() was called here, which hints that fatal signals aren't
1537 really fatal on some systems. If that's true, then some changes
1539 target_mourn_inferior ();
1541 print_stop_reason (SIGNAL_EXITED, stop_signal);
1542 singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
1543 stop_stepping (ecs);
1546 /* The following are the only cases in which we keep going;
1547 the above cases end in a continue or goto. */
1548 case TARGET_WAITKIND_FORKED:
1549 stop_signal = TARGET_SIGNAL_TRAP;
1550 pending_follow.kind = ecs->ws.kind;
1552 /* Ignore fork events reported for the parent; we're only
1553 interested in reacting to forks of the child. Note that
1554 we expect the child's fork event to be available if we
1555 waited for it now. */
1556 if (ptid_equal (inferior_ptid, ecs->ptid))
1558 pending_follow.fork_event.saw_parent_fork = 1;
1559 pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
1560 pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
1561 prepare_to_wait (ecs);
1566 pending_follow.fork_event.saw_child_fork = 1;
1567 pending_follow.fork_event.child_pid = PIDGET (ecs->ptid);
1568 pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
1571 stop_pc = read_pc_pid (ecs->ptid);
1572 ecs->saved_inferior_ptid = inferior_ptid;
1573 inferior_ptid = ecs->ptid;
1574 /* The second argument of bpstat_stop_status is meant to help
1575 distinguish between a breakpoint trap and a singlestep trap.
1576 This is only important on targets where DECR_PC_AFTER_BREAK
1577 is non-zero. The prev_pc test is meant to distinguish between
1578 singlestepping a trap instruction, and singlestepping thru a
1579 jump to the instruction following a trap instruction. */
1581 stop_bpstat = bpstat_stop_status (&stop_pc,
1582 currently_stepping (ecs) &&
1584 stop_pc - DECR_PC_AFTER_BREAK);
1585 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1586 inferior_ptid = ecs->saved_inferior_ptid;
1587 goto process_event_stop_test;
1589 /* If this a platform which doesn't allow a debugger to touch a
1590 vfork'd inferior until after it exec's, then we'd best keep
1591 our fingers entirely off the inferior, other than continuing
1592 it. This has the unfortunate side-effect that catchpoints
1593 of vforks will be ignored. But since the platform doesn't
1594 allow the inferior be touched at vfork time, there's really
1596 case TARGET_WAITKIND_VFORKED:
1597 stop_signal = TARGET_SIGNAL_TRAP;
1598 pending_follow.kind = ecs->ws.kind;
1600 /* Is this a vfork of the parent? If so, then give any
1601 vfork catchpoints a chance to trigger now. (It's
1602 dangerous to do so if the child canot be touched until
1603 it execs, and the child has not yet exec'd. We probably
1604 should warn the user to that effect when the catchpoint
1606 if (ptid_equal (ecs->ptid, inferior_ptid))
1608 pending_follow.fork_event.saw_parent_fork = 1;
1609 pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
1610 pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
1613 /* If we've seen the child's vfork event but cannot really touch
1614 the child until it execs, then we must continue the child now.
1615 Else, give any vfork catchpoints a chance to trigger now. */
1618 pending_follow.fork_event.saw_child_fork = 1;
1619 pending_follow.fork_event.child_pid = PIDGET (ecs->ptid);
1620 pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
1621 target_post_startup_inferior (pid_to_ptid
1622 (pending_follow.fork_event.
1624 follow_vfork_when_exec = !target_can_follow_vfork_prior_to_exec ();
1625 if (follow_vfork_when_exec)
1627 target_resume (ecs->ptid, 0, TARGET_SIGNAL_0);
1628 prepare_to_wait (ecs);
1633 stop_pc = read_pc ();
1634 /* The second argument of bpstat_stop_status is meant to help
1635 distinguish between a breakpoint trap and a singlestep trap.
1636 This is only important on targets where DECR_PC_AFTER_BREAK
1637 is non-zero. The prev_pc test is meant to distinguish between
1638 singlestepping a trap instruction, and singlestepping thru a
1639 jump to the instruction following a trap instruction. */
1641 stop_bpstat = bpstat_stop_status (&stop_pc,
1642 currently_stepping (ecs) &&
1644 stop_pc - DECR_PC_AFTER_BREAK);
1645 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1646 goto process_event_stop_test;
1648 case TARGET_WAITKIND_EXECD:
1649 stop_signal = TARGET_SIGNAL_TRAP;
1651 /* Is this a target which reports multiple exec events per actual
1652 call to exec()? (HP-UX using ptrace does, for example.) If so,
1653 ignore all but the last one. Just resume the exec'r, and wait
1654 for the next exec event. */
1655 if (inferior_ignoring_leading_exec_events)
1657 inferior_ignoring_leading_exec_events--;
1658 if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
1659 ENSURE_VFORKING_PARENT_REMAINS_STOPPED (pending_follow.fork_event.
1661 target_resume (ecs->ptid, 0, TARGET_SIGNAL_0);
1662 prepare_to_wait (ecs);
1665 inferior_ignoring_leading_exec_events =
1666 target_reported_exec_events_per_exec_call () - 1;
1668 pending_follow.execd_pathname =
1669 savestring (ecs->ws.value.execd_pathname,
1670 strlen (ecs->ws.value.execd_pathname));
1672 /* Did inferior_ptid exec, or did a (possibly not-yet-followed)
1673 child of a vfork exec?
1675 ??rehrauer: This is unabashedly an HP-UX specific thing. On
1676 HP-UX, events associated with a vforking inferior come in
1677 threes: a vfork event for the child (always first), followed
1678 a vfork event for the parent and an exec event for the child.
1679 The latter two can come in either order.
1681 If we get the parent vfork event first, life's good: We follow
1682 either the parent or child, and then the child's exec event is
1685 But if we get the child's exec event first, then we delay
1686 responding to it until we handle the parent's vfork. Because,
1687 otherwise we can't satisfy a "catch vfork". */
1688 if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
1690 pending_follow.fork_event.saw_child_exec = 1;
1692 /* On some targets, the child must be resumed before
1693 the parent vfork event is delivered. A single-step
1695 if (RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK ())
1696 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1697 /* We expect the parent vfork event to be available now. */
1698 prepare_to_wait (ecs);
1702 /* This causes the eventpoints and symbol table to be reset. Must
1703 do this now, before trying to determine whether to stop. */
1704 follow_exec (PIDGET (inferior_ptid), pending_follow.execd_pathname);
1705 xfree (pending_follow.execd_pathname);
1707 stop_pc = read_pc_pid (ecs->ptid);
1708 ecs->saved_inferior_ptid = inferior_ptid;
1709 inferior_ptid = ecs->ptid;
1710 /* The second argument of bpstat_stop_status is meant to help
1711 distinguish between a breakpoint trap and a singlestep trap.
1712 This is only important on targets where DECR_PC_AFTER_BREAK
1713 is non-zero. The prev_pc test is meant to distinguish between
1714 singlestepping a trap instruction, and singlestepping thru a
1715 jump to the instruction following a trap instruction. */
1717 stop_bpstat = bpstat_stop_status (&stop_pc,
1718 currently_stepping (ecs) &&
1720 stop_pc - DECR_PC_AFTER_BREAK);
1721 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1722 inferior_ptid = ecs->saved_inferior_ptid;
1723 goto process_event_stop_test;
1725 /* These syscall events are returned on HP-UX, as part of its
1726 implementation of page-protection-based "hardware" watchpoints.
1727 HP-UX has unfortunate interactions between page-protections and
1728 some system calls. Our solution is to disable hardware watches
1729 when a system call is entered, and reenable them when the syscall
1730 completes. The downside of this is that we may miss the precise
1731 point at which a watched piece of memory is modified. "Oh well."
1733 Note that we may have multiple threads running, which may each
1734 enter syscalls at roughly the same time. Since we don't have a
1735 good notion currently of whether a watched piece of memory is
1736 thread-private, we'd best not have any page-protections active
1737 when any thread is in a syscall. Thus, we only want to reenable
1738 hardware watches when no threads are in a syscall.
1740 Also, be careful not to try to gather much state about a thread
1741 that's in a syscall. It's frequently a losing proposition. */
1742 case TARGET_WAITKIND_SYSCALL_ENTRY:
1743 number_of_threads_in_syscalls++;
1744 if (number_of_threads_in_syscalls == 1)
1746 TARGET_DISABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
1748 resume (0, TARGET_SIGNAL_0);
1749 prepare_to_wait (ecs);
1752 /* Before examining the threads further, step this thread to
1753 get it entirely out of the syscall. (We get notice of the
1754 event when the thread is just on the verge of exiting a
1755 syscall. Stepping one instruction seems to get it back
1758 Note that although the logical place to reenable h/w watches
1759 is here, we cannot. We cannot reenable them before stepping
1760 the thread (this causes the next wait on the thread to hang).
1762 Nor can we enable them after stepping until we've done a wait.
1763 Thus, we simply set the flag ecs->enable_hw_watchpoints_after_wait
1764 here, which will be serviced immediately after the target
1766 case TARGET_WAITKIND_SYSCALL_RETURN:
1767 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1769 if (number_of_threads_in_syscalls > 0)
1771 number_of_threads_in_syscalls--;
1772 ecs->enable_hw_watchpoints_after_wait =
1773 (number_of_threads_in_syscalls == 0);
1775 prepare_to_wait (ecs);
1778 case TARGET_WAITKIND_STOPPED:
1779 stop_signal = ecs->ws.value.sig;
1782 /* We had an event in the inferior, but we are not interested
1783 in handling it at this level. The lower layers have already
1784 done what needs to be done, if anything. This case can
1785 occur only when the target is async or extended-async. One
1786 of the circumstamces for this to happen is when the
1787 inferior produces output for the console. The inferior has
1788 not stopped, and we are ignoring the event. */
1789 case TARGET_WAITKIND_IGNORE:
1790 ecs->wait_some_more = 1;
1794 /* We may want to consider not doing a resume here in order to give
1795 the user a chance to play with the new thread. It might be good
1796 to make that a user-settable option. */
1798 /* At this point, all threads are stopped (happens automatically in
1799 either the OS or the native code). Therefore we need to continue
1800 all threads in order to make progress. */
1801 if (ecs->new_thread_event)
1803 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
1804 prepare_to_wait (ecs);
1808 stop_pc = read_pc_pid (ecs->ptid);
1810 /* See if a thread hit a thread-specific breakpoint that was meant for
1811 another thread. If so, then step that thread past the breakpoint,
1814 if (stop_signal == TARGET_SIGNAL_TRAP)
1816 /* Check if a regular breakpoint has been hit before checking
1817 for a potential single step breakpoint. Otherwise, GDB will
1818 not see this breakpoint hit when stepping onto breakpoints. */
1819 if (breakpoints_inserted
1820 && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK))
1822 ecs->random_signal = 0;
1823 if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK,
1828 /* Saw a breakpoint, but it was hit by the wrong thread.
1830 if (DECR_PC_AFTER_BREAK)
1831 write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, ecs->ptid);
1833 remove_status = remove_breakpoints ();
1834 /* Did we fail to remove breakpoints? If so, try
1835 to set the PC past the bp. (There's at least
1836 one situation in which we can fail to remove
1837 the bp's: On HP-UX's that use ttrace, we can't
1838 change the address space of a vforking child
1839 process until the child exits (well, okay, not
1840 then either :-) or execs. */
1841 if (remove_status != 0)
1843 /* FIXME! This is obviously non-portable! */
1844 write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK + 4, ecs->ptid);
1845 /* We need to restart all the threads now,
1846 * unles we're running in scheduler-locked mode.
1847 * Use currently_stepping to determine whether to
1850 /* FIXME MVS: is there any reason not to call resume()? */
1851 if (scheduler_mode == schedlock_on)
1852 target_resume (ecs->ptid,
1853 currently_stepping (ecs), TARGET_SIGNAL_0);
1855 target_resume (RESUME_ALL,
1856 currently_stepping (ecs), TARGET_SIGNAL_0);
1857 prepare_to_wait (ecs);
1862 breakpoints_inserted = 0;
1863 if (!ptid_equal (inferior_ptid, ecs->ptid))
1864 context_switch (ecs);
1865 ecs->waiton_ptid = ecs->ptid;
1866 ecs->wp = &(ecs->ws);
1867 ecs->another_trap = 1;
1869 ecs->infwait_state = infwait_thread_hop_state;
1871 registers_changed ();
1876 else if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
1878 /* Readjust the stop_pc as it is off by DECR_PC_AFTER_BREAK
1879 compared to the value it would have if the system stepping
1880 capability was used. This allows the rest of the code in
1881 this function to use this address without having to worry
1882 whether software single step is in use or not. */
1883 if (DECR_PC_AFTER_BREAK)
1885 stop_pc -= DECR_PC_AFTER_BREAK;
1886 write_pc_pid (stop_pc, ecs->ptid);
1889 sw_single_step_trap_p = 1;
1890 ecs->random_signal = 0;
1894 ecs->random_signal = 1;
1896 /* See if something interesting happened to the non-current thread. If
1897 so, then switch to that thread, and eventually give control back to
1900 Note that if there's any kind of pending follow (i.e., of a fork,
1901 vfork or exec), we don't want to do this now. Rather, we'll let
1902 the next resume handle it. */
1903 if (!ptid_equal (ecs->ptid, inferior_ptid) &&
1904 (pending_follow.kind == TARGET_WAITKIND_SPURIOUS))
1908 /* If it's a random signal for a non-current thread, notify user
1909 if he's expressed an interest. */
1910 if (ecs->random_signal && signal_print[stop_signal])
1912 /* ??rehrauer: I don't understand the rationale for this code. If the
1913 inferior will stop as a result of this signal, then the act of handling
1914 the stop ought to print a message that's couches the stoppage in user
1915 terms, e.g., "Stopped for breakpoint/watchpoint". If the inferior
1916 won't stop as a result of the signal -- i.e., if the signal is merely
1917 a side-effect of something GDB's doing "under the covers" for the
1918 user, such as stepping threads over a breakpoint they shouldn't stop
1919 for -- then the message seems to be a serious annoyance at best.
1921 For now, remove the message altogether. */
1924 target_terminal_ours_for_output ();
1925 printf_filtered ("\nProgram received signal %s, %s.\n",
1926 target_signal_to_name (stop_signal),
1927 target_signal_to_string (stop_signal));
1928 gdb_flush (gdb_stdout);
1932 /* If it's not SIGTRAP and not a signal we want to stop for, then
1933 continue the thread. */
1935 if (stop_signal != TARGET_SIGNAL_TRAP && !signal_stop[stop_signal])
1938 target_terminal_inferior ();
1940 /* Clear the signal if it should not be passed. */
1941 if (signal_program[stop_signal] == 0)
1942 stop_signal = TARGET_SIGNAL_0;
1944 target_resume (ecs->ptid, 0, stop_signal);
1945 prepare_to_wait (ecs);
1949 /* It's a SIGTRAP or a signal we're interested in. Switch threads,
1950 and fall into the rest of wait_for_inferior(). */
1952 context_switch (ecs);
1955 context_hook (pid_to_thread_id (ecs->ptid));
1957 flush_cached_frames ();
1960 if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
1962 /* Pull the single step breakpoints out of the target. */
1963 SOFTWARE_SINGLE_STEP (0, 0);
1964 singlestep_breakpoints_inserted_p = 0;
1967 /* If PC is pointing at a nullified instruction, then step beyond
1968 it so that the user won't be confused when GDB appears to be ready
1971 /* if (INSTRUCTION_NULLIFIED && currently_stepping (ecs)) */
1972 if (INSTRUCTION_NULLIFIED)
1974 registers_changed ();
1975 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1977 /* We may have received a signal that we want to pass to
1978 the inferior; therefore, we must not clobber the waitstatus
1981 ecs->infwait_state = infwait_nullified_state;
1982 ecs->waiton_ptid = ecs->ptid;
1983 ecs->wp = &(ecs->tmpstatus);
1984 prepare_to_wait (ecs);
1988 /* It may not be necessary to disable the watchpoint to stop over
1989 it. For example, the PA can (with some kernel cooperation)
1990 single step over a watchpoint without disabling the watchpoint. */
1991 if (HAVE_STEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
1994 prepare_to_wait (ecs);
1998 /* It is far more common to need to disable a watchpoint to step
1999 the inferior over it. FIXME. What else might a debug
2000 register or page protection watchpoint scheme need here? */
2001 if (HAVE_NONSTEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
2003 /* At this point, we are stopped at an instruction which has
2004 attempted to write to a piece of memory under control of
2005 a watchpoint. The instruction hasn't actually executed
2006 yet. If we were to evaluate the watchpoint expression
2007 now, we would get the old value, and therefore no change
2008 would seem to have occurred.
2010 In order to make watchpoints work `right', we really need
2011 to complete the memory write, and then evaluate the
2012 watchpoint expression. The following code does that by
2013 removing the watchpoint (actually, all watchpoints and
2014 breakpoints), single-stepping the target, re-inserting
2015 watchpoints, and then falling through to let normal
2016 single-step processing handle proceed. Since this
2017 includes evaluating watchpoints, things will come to a
2018 stop in the correct manner. */
2020 if (DECR_PC_AFTER_BREAK)
2021 write_pc (stop_pc - DECR_PC_AFTER_BREAK);
2023 remove_breakpoints ();
2024 registers_changed ();
2025 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */
2027 ecs->waiton_ptid = ecs->ptid;
2028 ecs->wp = &(ecs->ws);
2029 ecs->infwait_state = infwait_nonstep_watch_state;
2030 prepare_to_wait (ecs);
2034 /* It may be possible to simply continue after a watchpoint. */
2035 if (HAVE_CONTINUABLE_WATCHPOINT)
2036 STOPPED_BY_WATCHPOINT (ecs->ws);
2038 ecs->stop_func_start = 0;
2039 ecs->stop_func_end = 0;
2040 ecs->stop_func_name = 0;
2041 /* Don't care about return value; stop_func_start and stop_func_name
2042 will both be 0 if it doesn't work. */
2043 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
2044 &ecs->stop_func_start, &ecs->stop_func_end);
2045 ecs->stop_func_start += FUNCTION_START_OFFSET;
2046 ecs->another_trap = 0;
2047 bpstat_clear (&stop_bpstat);
2049 stop_stack_dummy = 0;
2050 stop_print_frame = 1;
2051 ecs->random_signal = 0;
2052 stopped_by_random_signal = 0;
2053 breakpoints_failed = 0;
2055 /* Look at the cause of the stop, and decide what to do.
2056 The alternatives are:
2057 1) break; to really stop and return to the debugger,
2058 2) drop through to start up again
2059 (set ecs->another_trap to 1 to single step once)
2060 3) set ecs->random_signal to 1, and the decision between 1 and 2
2061 will be made according to the signal handling tables. */
2063 /* First, distinguish signals caused by the debugger from signals
2064 that have to do with the program's own actions.
2065 Note that breakpoint insns may cause SIGTRAP or SIGILL
2066 or SIGEMT, depending on the operating system version.
2067 Here we detect when a SIGILL or SIGEMT is really a breakpoint
2068 and change it to SIGTRAP. */
2070 if (stop_signal == TARGET_SIGNAL_TRAP
2071 || (breakpoints_inserted &&
2072 (stop_signal == TARGET_SIGNAL_ILL
2073 || stop_signal == TARGET_SIGNAL_EMT)) || stop_soon_quietly)
2075 if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
2077 stop_print_frame = 0;
2078 stop_stepping (ecs);
2081 if (stop_soon_quietly)
2083 stop_stepping (ecs);
2087 /* Don't even think about breakpoints
2088 if just proceeded over a breakpoint.
2090 However, if we are trying to proceed over a breakpoint
2091 and end up in sigtramp, then through_sigtramp_breakpoint
2092 will be set and we should check whether we've hit the
2094 if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected
2095 && through_sigtramp_breakpoint == NULL)
2096 bpstat_clear (&stop_bpstat);
2099 /* See if there is a breakpoint at the current PC. */
2101 /* The second argument of bpstat_stop_status is meant to help
2102 distinguish between a breakpoint trap and a singlestep trap.
2103 This is only important on targets where DECR_PC_AFTER_BREAK
2104 is non-zero. The prev_pc test is meant to distinguish between
2105 singlestepping a trap instruction, and singlestepping thru a
2106 jump to the instruction following a trap instruction. */
2111 /* Pass TRUE if our reason for stopping is something other
2112 than hitting a breakpoint. We do this by checking that
2113 either we detected earlier a software single step trap or
2114 1) stepping is going on and 2) we didn't hit a breakpoint
2115 in a signal handler without an intervening stop in
2116 sigtramp, which is detected by a new stack pointer value
2117 below any usual function calling stack adjustments. */
2118 sw_single_step_trap_p
2119 || (currently_stepping (ecs)
2120 && prev_pc != stop_pc - DECR_PC_AFTER_BREAK
2122 && INNER_THAN (read_sp (), (step_sp - 16)))));
2123 /* Following in case break condition called a
2125 stop_print_frame = 1;
2128 if (stop_signal == TARGET_SIGNAL_TRAP)
2130 = !(bpstat_explains_signal (stop_bpstat)
2132 || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
2133 && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
2134 FRAME_FP (get_current_frame ())))
2135 || (step_range_end && step_resume_breakpoint == NULL));
2139 ecs->random_signal = !(bpstat_explains_signal (stop_bpstat)
2140 /* End of a stack dummy. Some systems (e.g. Sony
2141 news) give another signal besides SIGTRAP, so
2142 check here as well as above. */
2143 || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
2144 && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
2148 if (!ecs->random_signal)
2149 stop_signal = TARGET_SIGNAL_TRAP;
2153 /* When we reach this point, we've pretty much decided
2154 that the reason for stopping must've been a random
2155 (unexpected) signal. */
2158 ecs->random_signal = 1;
2159 /* If a fork, vfork or exec event was seen, then there are two
2160 possible responses we can make:
2162 1. If a catchpoint triggers for the event (ecs->random_signal == 0),
2163 then we must stop now and issue a prompt. We will resume
2164 the inferior when the user tells us to.
2165 2. If no catchpoint triggers for the event (ecs->random_signal == 1),
2166 then we must resume the inferior now and keep checking.
2168 In either case, we must take appropriate steps to "follow" the
2169 the fork/vfork/exec when the inferior is resumed. For example,
2170 if follow-fork-mode is "child", then we must detach from the
2171 parent inferior and follow the new child inferior.
2173 In either case, setting pending_follow causes the next resume()
2174 to take the appropriate following action. */
2175 process_event_stop_test:
2176 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
2178 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2181 stop_signal = TARGET_SIGNAL_0;
2186 else if (ecs->ws.kind == TARGET_WAITKIND_VFORKED)
2188 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2190 stop_signal = TARGET_SIGNAL_0;
2195 else if (ecs->ws.kind == TARGET_WAITKIND_EXECD)
2197 pending_follow.kind = ecs->ws.kind;
2198 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2201 stop_signal = TARGET_SIGNAL_0;
2207 /* For the program's own signals, act according to
2208 the signal handling tables. */
2210 if (ecs->random_signal)
2212 /* Signal not for debugging purposes. */
2215 stopped_by_random_signal = 1;
2217 if (signal_print[stop_signal])
2220 target_terminal_ours_for_output ();
2221 print_stop_reason (SIGNAL_RECEIVED, stop_signal);
2223 if (signal_stop[stop_signal])
2225 stop_stepping (ecs);
2228 /* If not going to stop, give terminal back
2229 if we took it away. */
2231 target_terminal_inferior ();
2233 /* Clear the signal if it should not be passed. */
2234 if (signal_program[stop_signal] == 0)
2235 stop_signal = TARGET_SIGNAL_0;
2237 /* I'm not sure whether this needs to be check_sigtramp2 or
2238 whether it could/should be keep_going.
2240 This used to jump to step_over_function if we are stepping,
2243 Suppose the user does a `next' over a function call, and while
2244 that call is in progress, the inferior receives a signal for
2245 which GDB does not stop (i.e., signal_stop[SIG] is false). In
2246 that case, when we reach this point, there is already a
2247 step-resume breakpoint established, right where it should be:
2248 immediately after the function call the user is "next"-ing
2249 over. If we call step_over_function now, two bad things
2252 - we'll create a new breakpoint, at wherever the current
2253 frame's return address happens to be. That could be
2254 anywhere, depending on what function call happens to be on
2255 the top of the stack at that point. Point is, it's probably
2256 not where we need it.
2258 - the existing step-resume breakpoint (which is at the correct
2259 address) will get orphaned: step_resume_breakpoint will point
2260 to the new breakpoint, and the old step-resume breakpoint
2261 will never be cleaned up.
2263 The old behavior was meant to help HP-UX single-step out of
2264 sigtramps. It would place the new breakpoint at prev_pc, which
2265 was certainly wrong. I don't know the details there, so fixing
2266 this probably breaks that. As with anything else, it's up to
2267 the HP-UX maintainer to furnish a fix that doesn't break other
2268 platforms. --JimB, 20 May 1999 */
2269 check_sigtramp2 (ecs);
2274 /* Handle cases caused by hitting a breakpoint. */
2276 CORE_ADDR jmp_buf_pc;
2277 struct bpstat_what what;
2279 what = bpstat_what (stop_bpstat);
2281 if (what.call_dummy)
2283 stop_stack_dummy = 1;
2285 trap_expected_after_continue = 1;
2289 switch (what.main_action)
2291 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
2292 /* If we hit the breakpoint at longjmp, disable it for the
2293 duration of this command. Then, install a temporary
2294 breakpoint at the target of the jmp_buf. */
2295 disable_longjmp_breakpoint ();
2296 remove_breakpoints ();
2297 breakpoints_inserted = 0;
2298 if (!GET_LONGJMP_TARGET_P () || !GET_LONGJMP_TARGET (&jmp_buf_pc))
2304 /* Need to blow away step-resume breakpoint, as it
2305 interferes with us */
2306 if (step_resume_breakpoint != NULL)
2308 delete_step_resume_breakpoint (&step_resume_breakpoint);
2310 /* Not sure whether we need to blow this away too, but probably
2311 it is like the step-resume breakpoint. */
2312 if (through_sigtramp_breakpoint != NULL)
2314 delete_breakpoint (through_sigtramp_breakpoint);
2315 through_sigtramp_breakpoint = NULL;
2319 /* FIXME - Need to implement nested temporary breakpoints */
2320 if (step_over_calls > 0)
2321 set_longjmp_resume_breakpoint (jmp_buf_pc, get_current_frame ());
2324 set_longjmp_resume_breakpoint (jmp_buf_pc, NULL);
2325 ecs->handling_longjmp = 1; /* FIXME */
2329 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
2330 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
2331 remove_breakpoints ();
2332 breakpoints_inserted = 0;
2334 /* FIXME - Need to implement nested temporary breakpoints */
2336 && (INNER_THAN (FRAME_FP (get_current_frame ()),
2337 step_frame_address)))
2339 ecs->another_trap = 1;
2344 disable_longjmp_breakpoint ();
2345 ecs->handling_longjmp = 0; /* FIXME */
2346 if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
2348 /* else fallthrough */
2350 case BPSTAT_WHAT_SINGLE:
2351 if (breakpoints_inserted)
2353 remove_breakpoints ();
2355 breakpoints_inserted = 0;
2356 ecs->another_trap = 1;
2357 /* Still need to check other stuff, at least the case
2358 where we are stepping and step out of the right range. */
2361 case BPSTAT_WHAT_STOP_NOISY:
2362 stop_print_frame = 1;
2364 /* We are about to nuke the step_resume_breakpoint and
2365 through_sigtramp_breakpoint via the cleanup chain, so
2366 no need to worry about it here. */
2368 stop_stepping (ecs);
2371 case BPSTAT_WHAT_STOP_SILENT:
2372 stop_print_frame = 0;
2374 /* We are about to nuke the step_resume_breakpoint and
2375 through_sigtramp_breakpoint via the cleanup chain, so
2376 no need to worry about it here. */
2378 stop_stepping (ecs);
2381 case BPSTAT_WHAT_STEP_RESUME:
2382 /* This proably demands a more elegant solution, but, yeah
2385 This function's use of the simple variable
2386 step_resume_breakpoint doesn't seem to accomodate
2387 simultaneously active step-resume bp's, although the
2388 breakpoint list certainly can.
2390 If we reach here and step_resume_breakpoint is already
2391 NULL, then apparently we have multiple active
2392 step-resume bp's. We'll just delete the breakpoint we
2393 stopped at, and carry on.
2395 Correction: what the code currently does is delete a
2396 step-resume bp, but it makes no effort to ensure that
2397 the one deleted is the one currently stopped at. MVS */
2399 if (step_resume_breakpoint == NULL)
2401 step_resume_breakpoint =
2402 bpstat_find_step_resume_breakpoint (stop_bpstat);
2404 delete_step_resume_breakpoint (&step_resume_breakpoint);
2407 case BPSTAT_WHAT_THROUGH_SIGTRAMP:
2408 if (through_sigtramp_breakpoint)
2409 delete_breakpoint (through_sigtramp_breakpoint);
2410 through_sigtramp_breakpoint = NULL;
2412 /* If were waiting for a trap, hitting the step_resume_break
2413 doesn't count as getting it. */
2415 ecs->another_trap = 1;
2418 case BPSTAT_WHAT_CHECK_SHLIBS:
2419 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
2422 /* Remove breakpoints, we eventually want to step over the
2423 shlib event breakpoint, and SOLIB_ADD might adjust
2424 breakpoint addresses via breakpoint_re_set. */
2425 if (breakpoints_inserted)
2426 remove_breakpoints ();
2427 breakpoints_inserted = 0;
2429 /* Check for any newly added shared libraries if we're
2430 supposed to be adding them automatically. Switch
2431 terminal for any messages produced by
2432 breakpoint_re_set. */
2433 target_terminal_ours_for_output ();
2434 SOLIB_ADD (NULL, 0, NULL, auto_solib_add);
2435 target_terminal_inferior ();
2437 /* Try to reenable shared library breakpoints, additional
2438 code segments in shared libraries might be mapped in now. */
2439 re_enable_breakpoints_in_shlibs ();
2441 /* If requested, stop when the dynamic linker notifies
2442 gdb of events. This allows the user to get control
2443 and place breakpoints in initializer routines for
2444 dynamically loaded objects (among other things). */
2445 if (stop_on_solib_events)
2447 stop_stepping (ecs);
2451 /* If we stopped due to an explicit catchpoint, then the
2452 (see above) call to SOLIB_ADD pulled in any symbols
2453 from a newly-loaded library, if appropriate.
2455 We do want the inferior to stop, but not where it is
2456 now, which is in the dynamic linker callback. Rather,
2457 we would like it stop in the user's program, just after
2458 the call that caused this catchpoint to trigger. That
2459 gives the user a more useful vantage from which to
2460 examine their program's state. */
2461 else if (what.main_action ==
2462 BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
2464 /* ??rehrauer: If I could figure out how to get the
2465 right return PC from here, we could just set a temp
2466 breakpoint and resume. I'm not sure we can without
2467 cracking open the dld's shared libraries and sniffing
2468 their unwind tables and text/data ranges, and that's
2469 not a terribly portable notion.
2471 Until that time, we must step the inferior out of the
2472 dld callback, and also out of the dld itself (and any
2473 code or stubs in libdld.sl, such as "shl_load" and
2474 friends) until we reach non-dld code. At that point,
2475 we can stop stepping. */
2476 bpstat_get_triggered_catchpoints (stop_bpstat,
2478 stepping_through_solib_catchpoints);
2479 ecs->stepping_through_solib_after_catch = 1;
2481 /* Be sure to lift all breakpoints, so the inferior does
2482 actually step past this point... */
2483 ecs->another_trap = 1;
2488 /* We want to step over this breakpoint, then keep going. */
2489 ecs->another_trap = 1;
2496 case BPSTAT_WHAT_LAST:
2497 /* Not a real code, but listed here to shut up gcc -Wall. */
2499 case BPSTAT_WHAT_KEEP_CHECKING:
2504 /* We come here if we hit a breakpoint but should not
2505 stop for it. Possibly we also were stepping
2506 and should stop for that. So fall through and
2507 test for stepping. But, if not stepping,
2510 /* Are we stepping to get the inferior out of the dynamic
2511 linker's hook (and possibly the dld itself) after catching
2513 if (ecs->stepping_through_solib_after_catch)
2515 #if defined(SOLIB_ADD)
2516 /* Have we reached our destination? If not, keep going. */
2517 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc))
2519 ecs->another_trap = 1;
2524 /* Else, stop and report the catchpoint(s) whose triggering
2525 caused us to begin stepping. */
2526 ecs->stepping_through_solib_after_catch = 0;
2527 bpstat_clear (&stop_bpstat);
2528 stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints);
2529 bpstat_clear (&ecs->stepping_through_solib_catchpoints);
2530 stop_print_frame = 1;
2531 stop_stepping (ecs);
2535 if (!CALL_DUMMY_BREAKPOINT_OFFSET_P)
2537 /* This is the old way of detecting the end of the stack dummy.
2538 An architecture which defines CALL_DUMMY_BREAKPOINT_OFFSET gets
2539 handled above. As soon as we can test it on all of them, all
2540 architectures should define it. */
2542 /* If this is the breakpoint at the end of a stack dummy,
2543 just stop silently, unless the user was doing an si/ni, in which
2544 case she'd better know what she's doing. */
2546 if (CALL_DUMMY_HAS_COMPLETED (stop_pc, read_sp (),
2547 FRAME_FP (get_current_frame ()))
2550 stop_print_frame = 0;
2551 stop_stack_dummy = 1;
2553 trap_expected_after_continue = 1;
2555 stop_stepping (ecs);
2560 if (step_resume_breakpoint)
2562 /* Having a step-resume breakpoint overrides anything
2563 else having to do with stepping commands until
2564 that breakpoint is reached. */
2565 /* I'm not sure whether this needs to be check_sigtramp2 or
2566 whether it could/should be keep_going. */
2567 check_sigtramp2 (ecs);
2572 if (step_range_end == 0)
2574 /* Likewise if we aren't even stepping. */
2575 /* I'm not sure whether this needs to be check_sigtramp2 or
2576 whether it could/should be keep_going. */
2577 check_sigtramp2 (ecs);
2582 /* If stepping through a line, keep going if still within it.
2584 Note that step_range_end is the address of the first instruction
2585 beyond the step range, and NOT the address of the last instruction
2587 if (stop_pc >= step_range_start && stop_pc < step_range_end)
2589 /* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal.
2590 So definately need to check for sigtramp here. */
2591 check_sigtramp2 (ecs);
2596 /* We stepped out of the stepping range. */
2598 /* If we are stepping at the source level and entered the runtime
2599 loader dynamic symbol resolution code, we keep on single stepping
2600 until we exit the run time loader code and reach the callee's
2602 if (step_over_calls == STEP_OVER_UNDEBUGGABLE
2603 && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc))
2605 CORE_ADDR pc_after_resolver = SKIP_SOLIB_RESOLVER (stop_pc);
2607 if (pc_after_resolver)
2609 /* Set up a step-resume breakpoint at the address
2610 indicated by SKIP_SOLIB_RESOLVER. */
2611 struct symtab_and_line sr_sal;
2613 sr_sal.pc = pc_after_resolver;
2615 check_for_old_step_resume_breakpoint ();
2616 step_resume_breakpoint =
2617 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2618 if (breakpoints_inserted)
2619 insert_breakpoints ();
2626 /* We can't update step_sp every time through the loop, because
2627 reading the stack pointer would slow down stepping too much.
2628 But we can update it every time we leave the step range. */
2629 ecs->update_step_sp = 1;
2631 /* Did we just take a signal? */
2632 if (PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2633 && !PC_IN_SIGTRAMP (prev_pc, prev_func_name)
2634 && INNER_THAN (read_sp (), step_sp))
2636 /* We've just taken a signal; go until we are back to
2637 the point where we took it and one more. */
2639 /* Note: The test above succeeds not only when we stepped
2640 into a signal handler, but also when we step past the last
2641 statement of a signal handler and end up in the return stub
2642 of the signal handler trampoline. To distinguish between
2643 these two cases, check that the frame is INNER_THAN the
2644 previous one below. pai/1997-09-11 */
2648 CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
2650 if (INNER_THAN (current_frame, step_frame_address))
2652 /* We have just taken a signal; go until we are back to
2653 the point where we took it and one more. */
2655 /* This code is needed at least in the following case:
2656 The user types "next" and then a signal arrives (before
2657 the "next" is done). */
2659 /* Note that if we are stopped at a breakpoint, then we need
2660 the step_resume breakpoint to override any breakpoints at
2661 the same location, so that we will still step over the
2662 breakpoint even though the signal happened. */
2663 struct symtab_and_line sr_sal;
2666 sr_sal.symtab = NULL;
2668 sr_sal.pc = prev_pc;
2669 /* We could probably be setting the frame to
2670 step_frame_address; I don't think anyone thought to
2672 check_for_old_step_resume_breakpoint ();
2673 step_resume_breakpoint =
2674 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2675 if (breakpoints_inserted)
2676 insert_breakpoints ();
2680 /* We just stepped out of a signal handler and into
2681 its calling trampoline.
2683 Normally, we'd call step_over_function from
2684 here, but for some reason GDB can't unwind the
2685 stack correctly to find the real PC for the point
2686 user code where the signal trampoline will return
2687 -- FRAME_SAVED_PC fails, at least on HP-UX 10.20.
2688 But signal trampolines are pretty small stubs of
2689 code, anyway, so it's OK instead to just
2690 single-step out. Note: assuming such trampolines
2691 don't exhibit recursion on any platform... */
2692 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
2693 &ecs->stop_func_start,
2694 &ecs->stop_func_end);
2695 /* Readjust stepping range */
2696 step_range_start = ecs->stop_func_start;
2697 step_range_end = ecs->stop_func_end;
2698 ecs->stepping_through_sigtramp = 1;
2703 /* If this is stepi or nexti, make sure that the stepping range
2704 gets us past that instruction. */
2705 if (step_range_end == 1)
2706 /* FIXME: Does this run afoul of the code below which, if
2707 we step into the middle of a line, resets the stepping
2709 step_range_end = (step_range_start = prev_pc) + 1;
2711 ecs->remove_breakpoints_on_following_step = 1;
2716 if (stop_pc == ecs->stop_func_start /* Quick test */
2717 || (in_prologue (stop_pc, ecs->stop_func_start) &&
2718 !IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2719 || IN_SOLIB_CALL_TRAMPOLINE (stop_pc, ecs->stop_func_name)
2720 || ecs->stop_func_name == 0)
2722 /* It's a subroutine call. */
2724 if ((step_over_calls == STEP_OVER_NONE)
2725 || ((step_range_end == 1)
2726 && in_prologue (prev_pc, ecs->stop_func_start)))
2728 /* I presume that step_over_calls is only 0 when we're
2729 supposed to be stepping at the assembly language level
2730 ("stepi"). Just stop. */
2731 /* Also, maybe we just did a "nexti" inside a prolog,
2732 so we thought it was a subroutine call but it was not.
2733 Stop as well. FENN */
2735 print_stop_reason (END_STEPPING_RANGE, 0);
2736 stop_stepping (ecs);
2740 if (step_over_calls == STEP_OVER_ALL || IGNORE_HELPER_CALL (stop_pc))
2742 /* We're doing a "next". */
2744 if (PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2745 && INNER_THAN (step_frame_address, read_sp ()))
2746 /* We stepped out of a signal handler, and into its
2747 calling trampoline. This is misdetected as a
2748 subroutine call, but stepping over the signal
2749 trampoline isn't such a bad idea. In order to do
2750 that, we have to ignore the value in
2751 step_frame_address, since that doesn't represent the
2752 frame that'll reach when we return from the signal
2753 trampoline. Otherwise we'll probably continue to the
2754 end of the program. */
2755 step_frame_address = 0;
2757 step_over_function (ecs);
2762 /* If we are in a function call trampoline (a stub between
2763 the calling routine and the real function), locate the real
2764 function. That's what tells us (a) whether we want to step
2765 into it at all, and (b) what prologue we want to run to
2766 the end of, if we do step into it. */
2767 tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
2769 ecs->stop_func_start = tmp;
2772 tmp = DYNAMIC_TRAMPOLINE_NEXTPC (stop_pc);
2775 struct symtab_and_line xxx;
2776 /* Why isn't this s_a_l called "sr_sal", like all of the
2777 other s_a_l's where this code is duplicated? */
2778 INIT_SAL (&xxx); /* initialize to zeroes */
2780 xxx.section = find_pc_overlay (xxx.pc);
2781 check_for_old_step_resume_breakpoint ();
2782 step_resume_breakpoint =
2783 set_momentary_breakpoint (xxx, NULL, bp_step_resume);
2784 insert_breakpoints ();
2790 /* If we have line number information for the function we
2791 are thinking of stepping into, step into it.
2793 If there are several symtabs at that PC (e.g. with include
2794 files), just want to know whether *any* of them have line
2795 numbers. find_pc_line handles this. */
2797 struct symtab_and_line tmp_sal;
2799 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
2800 if (tmp_sal.line != 0)
2802 step_into_function (ecs);
2807 /* If we have no line number and the step-stop-if-no-debug
2808 is set, we stop the step so that the user has a chance to
2809 switch in assembly mode. */
2810 if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug)
2813 print_stop_reason (END_STEPPING_RANGE, 0);
2814 stop_stepping (ecs);
2818 step_over_function (ecs);
2824 /* We've wandered out of the step range. */
2826 ecs->sal = find_pc_line (stop_pc, 0);
2828 if (step_range_end == 1)
2830 /* It is stepi or nexti. We always want to stop stepping after
2833 print_stop_reason (END_STEPPING_RANGE, 0);
2834 stop_stepping (ecs);
2838 /* If we're in the return path from a shared library trampoline,
2839 we want to proceed through the trampoline when stepping. */
2840 if (IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2844 /* Determine where this trampoline returns. */
2845 tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
2847 /* Only proceed through if we know where it's going. */
2850 /* And put the step-breakpoint there and go until there. */
2851 struct symtab_and_line sr_sal;
2853 INIT_SAL (&sr_sal); /* initialize to zeroes */
2855 sr_sal.section = find_pc_overlay (sr_sal.pc);
2856 /* Do not specify what the fp should be when we stop
2857 since on some machines the prologue
2858 is where the new fp value is established. */
2859 check_for_old_step_resume_breakpoint ();
2860 step_resume_breakpoint =
2861 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2862 if (breakpoints_inserted)
2863 insert_breakpoints ();
2865 /* Restart without fiddling with the step ranges or
2872 if (ecs->sal.line == 0)
2874 /* We have no line number information. That means to stop
2875 stepping (does this always happen right after one instruction,
2876 when we do "s" in a function with no line numbers,
2877 or can this happen as a result of a return or longjmp?). */
2879 print_stop_reason (END_STEPPING_RANGE, 0);
2880 stop_stepping (ecs);
2884 if ((stop_pc == ecs->sal.pc)
2885 && (ecs->current_line != ecs->sal.line
2886 || ecs->current_symtab != ecs->sal.symtab))
2888 /* We are at the start of a different line. So stop. Note that
2889 we don't stop if we step into the middle of a different line.
2890 That is said to make things like for (;;) statements work
2893 print_stop_reason (END_STEPPING_RANGE, 0);
2894 stop_stepping (ecs);
2898 /* We aren't done stepping.
2900 Optimize by setting the stepping range to the line.
2901 (We might not be in the original line, but if we entered a
2902 new line in mid-statement, we continue stepping. This makes
2903 things like for(;;) statements work better.) */
2905 if (ecs->stop_func_end && ecs->sal.end >= ecs->stop_func_end)
2907 /* If this is the last line of the function, don't keep stepping
2908 (it would probably step us out of the function).
2909 This is particularly necessary for a one-line function,
2910 in which after skipping the prologue we better stop even though
2911 we will be in mid-line. */
2913 print_stop_reason (END_STEPPING_RANGE, 0);
2914 stop_stepping (ecs);
2917 step_range_start = ecs->sal.pc;
2918 step_range_end = ecs->sal.end;
2919 step_frame_address = FRAME_FP (get_current_frame ());
2920 ecs->current_line = ecs->sal.line;
2921 ecs->current_symtab = ecs->sal.symtab;
2923 /* In the case where we just stepped out of a function into the middle
2924 of a line of the caller, continue stepping, but step_frame_address
2925 must be modified to current frame */
2927 CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
2928 if (!(INNER_THAN (current_frame, step_frame_address)))
2929 step_frame_address = current_frame;
2935 /* Are we in the middle of stepping? */
2938 currently_stepping (struct execution_control_state *ecs)
2940 return ((through_sigtramp_breakpoint == NULL
2941 && !ecs->handling_longjmp
2942 && ((step_range_end && step_resume_breakpoint == NULL)
2944 || ecs->stepping_through_solib_after_catch
2945 || bpstat_should_step ());
2949 check_sigtramp2 (struct execution_control_state *ecs)
2952 && PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2953 && !PC_IN_SIGTRAMP (prev_pc, prev_func_name)
2954 && INNER_THAN (read_sp (), step_sp))
2956 /* What has happened here is that we have just stepped the
2957 inferior with a signal (because it is a signal which
2958 shouldn't make us stop), thus stepping into sigtramp.
2960 So we need to set a step_resume_break_address breakpoint and
2961 continue until we hit it, and then step. FIXME: This should
2962 be more enduring than a step_resume breakpoint; we should
2963 know that we will later need to keep going rather than
2964 re-hitting the breakpoint here (see the testsuite,
2965 gdb.base/signals.exp where it says "exceedingly difficult"). */
2967 struct symtab_and_line sr_sal;
2969 INIT_SAL (&sr_sal); /* initialize to zeroes */
2970 sr_sal.pc = prev_pc;
2971 sr_sal.section = find_pc_overlay (sr_sal.pc);
2972 /* We perhaps could set the frame if we kept track of what the
2973 frame corresponding to prev_pc was. But we don't, so don't. */
2974 through_sigtramp_breakpoint =
2975 set_momentary_breakpoint (sr_sal, NULL, bp_through_sigtramp);
2976 if (breakpoints_inserted)
2977 insert_breakpoints ();
2979 ecs->remove_breakpoints_on_following_step = 1;
2980 ecs->another_trap = 1;
2984 /* Subroutine call with source code we should not step over. Do step
2985 to the first line of code in it. */
2988 step_into_function (struct execution_control_state *ecs)
2991 struct symtab_and_line sr_sal;
2993 s = find_pc_symtab (stop_pc);
2994 if (s && s->language != language_asm)
2995 ecs->stop_func_start = SKIP_PROLOGUE (ecs->stop_func_start);
2997 ecs->sal = find_pc_line (ecs->stop_func_start, 0);
2998 /* Use the step_resume_break to step until the end of the prologue,
2999 even if that involves jumps (as it seems to on the vax under
3001 /* If the prologue ends in the middle of a source line, continue to
3002 the end of that source line (if it is still within the function).
3003 Otherwise, just go to end of prologue. */
3004 #ifdef PROLOGUE_FIRSTLINE_OVERLAP
3005 /* no, don't either. It skips any code that's legitimately on the
3009 && ecs->sal.pc != ecs->stop_func_start
3010 && ecs->sal.end < ecs->stop_func_end)
3011 ecs->stop_func_start = ecs->sal.end;
3014 if (ecs->stop_func_start == stop_pc)
3016 /* We are already there: stop now. */
3018 print_stop_reason (END_STEPPING_RANGE, 0);
3019 stop_stepping (ecs);
3024 /* Put the step-breakpoint there and go until there. */
3025 INIT_SAL (&sr_sal); /* initialize to zeroes */
3026 sr_sal.pc = ecs->stop_func_start;
3027 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
3028 /* Do not specify what the fp should be when we stop since on
3029 some machines the prologue is where the new fp value is
3031 check_for_old_step_resume_breakpoint ();
3032 step_resume_breakpoint =
3033 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
3034 if (breakpoints_inserted)
3035 insert_breakpoints ();
3037 /* And make sure stepping stops right away then. */
3038 step_range_end = step_range_start;
3043 /* We've just entered a callee, and we wish to resume until it returns
3044 to the caller. Setting a step_resume breakpoint on the return
3045 address will catch a return from the callee.
3047 However, if the callee is recursing, we want to be careful not to
3048 catch returns of those recursive calls, but only of THIS instance
3051 To do this, we set the step_resume bp's frame to our current
3052 caller's frame (step_frame_address, which is set by the "next" or
3053 "until" command, before execution begins). */
3056 step_over_function (struct execution_control_state *ecs)
3058 struct symtab_and_line sr_sal;
3060 INIT_SAL (&sr_sal); /* initialize to zeros */
3061 sr_sal.pc = ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ()));
3062 sr_sal.section = find_pc_overlay (sr_sal.pc);
3064 check_for_old_step_resume_breakpoint ();
3065 step_resume_breakpoint =
3066 set_momentary_breakpoint (sr_sal, get_current_frame (), bp_step_resume);
3068 if (step_frame_address && !IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
3069 step_resume_breakpoint->frame = step_frame_address;
3071 if (breakpoints_inserted)
3072 insert_breakpoints ();
3076 stop_stepping (struct execution_control_state *ecs)
3078 if (target_has_execution)
3080 /* Are we stopping for a vfork event? We only stop when we see
3081 the child's event. However, we may not yet have seen the
3082 parent's event. And, inferior_ptid is still set to the
3083 parent's pid, until we resume again and follow either the
3086 To ensure that we can really touch inferior_ptid (aka, the
3087 parent process) -- which calls to functions like read_pc
3088 implicitly do -- wait on the parent if necessary. */
3089 if ((pending_follow.kind == TARGET_WAITKIND_VFORKED)
3090 && !pending_follow.fork_event.saw_parent_fork)
3096 if (target_wait_hook)
3097 parent_ptid = target_wait_hook (pid_to_ptid (-1), &(ecs->ws));
3099 parent_ptid = target_wait (pid_to_ptid (-1), &(ecs->ws));
3101 while (!ptid_equal (parent_ptid, inferior_ptid));
3104 /* Assuming the inferior still exists, set these up for next
3105 time, just like we did above if we didn't break out of the
3107 prev_pc = read_pc ();
3108 prev_func_start = ecs->stop_func_start;
3109 prev_func_name = ecs->stop_func_name;
3112 /* Let callers know we don't want to wait for the inferior anymore. */
3113 ecs->wait_some_more = 0;
3116 /* This function handles various cases where we need to continue
3117 waiting for the inferior. */
3118 /* (Used to be the keep_going: label in the old wait_for_inferior) */
3121 keep_going (struct execution_control_state *ecs)
3123 /* ??rehrauer: ttrace on HP-UX theoretically allows one to debug a
3124 vforked child between its creation and subsequent exit or call to
3125 exec(). However, I had big problems in this rather creaky exec
3126 engine, getting that to work. The fundamental problem is that
3127 I'm trying to debug two processes via an engine that only
3128 understands a single process with possibly multiple threads.
3130 Hence, this spot is known to have problems when
3131 target_can_follow_vfork_prior_to_exec returns 1. */
3133 /* Save the pc before execution, to compare with pc after stop. */
3134 prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
3135 prev_func_start = ecs->stop_func_start; /* Ok, since if DECR_PC_AFTER
3136 BREAK is defined, the
3137 original pc would not have
3138 been at the start of a
3140 prev_func_name = ecs->stop_func_name;
3142 if (ecs->update_step_sp)
3143 step_sp = read_sp ();
3144 ecs->update_step_sp = 0;
3146 /* If we did not do break;, it means we should keep running the
3147 inferior and not return to debugger. */
3149 if (trap_expected && stop_signal != TARGET_SIGNAL_TRAP)
3151 /* We took a signal (which we are supposed to pass through to
3152 the inferior, else we'd have done a break above) and we
3153 haven't yet gotten our trap. Simply continue. */
3154 resume (currently_stepping (ecs), stop_signal);
3158 /* Either the trap was not expected, but we are continuing
3159 anyway (the user asked that this signal be passed to the
3162 The signal was SIGTRAP, e.g. it was our signal, but we
3163 decided we should resume from it.
3165 We're going to run this baby now!
3167 Insert breakpoints now, unless we are trying to one-proceed
3168 past a breakpoint. */
3169 /* If we've just finished a special step resume and we don't
3170 want to hit a breakpoint, pull em out. */
3171 if (step_resume_breakpoint == NULL
3172 && through_sigtramp_breakpoint == NULL
3173 && ecs->remove_breakpoints_on_following_step)
3175 ecs->remove_breakpoints_on_following_step = 0;
3176 remove_breakpoints ();
3177 breakpoints_inserted = 0;
3179 else if (!breakpoints_inserted &&
3180 (through_sigtramp_breakpoint != NULL || !ecs->another_trap))
3182 breakpoints_failed = insert_breakpoints ();
3183 if (breakpoints_failed)
3185 stop_stepping (ecs);
3188 breakpoints_inserted = 1;
3191 trap_expected = ecs->another_trap;
3193 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3194 specifies that such a signal should be delivered to the
3197 Typically, this would occure when a user is debugging a
3198 target monitor on a simulator: the target monitor sets a
3199 breakpoint; the simulator encounters this break-point and
3200 halts the simulation handing control to GDB; GDB, noteing
3201 that the break-point isn't valid, returns control back to the
3202 simulator; the simulator then delivers the hardware
3203 equivalent of a SIGNAL_TRAP to the program being debugged. */
3205 if (stop_signal == TARGET_SIGNAL_TRAP && !signal_program[stop_signal])
3206 stop_signal = TARGET_SIGNAL_0;
3208 #ifdef SHIFT_INST_REGS
3209 /* I'm not sure when this following segment applies. I do know,
3210 now, that we shouldn't rewrite the regs when we were stopped
3211 by a random signal from the inferior process. */
3212 /* FIXME: Shouldn't this be based on the valid bit of the SXIP?
3213 (this is only used on the 88k). */
3215 if (!bpstat_explains_signal (stop_bpstat)
3216 && (stop_signal != TARGET_SIGNAL_CHLD) && !stopped_by_random_signal)
3218 #endif /* SHIFT_INST_REGS */
3220 resume (currently_stepping (ecs), stop_signal);
3223 prepare_to_wait (ecs);
3226 /* This function normally comes after a resume, before
3227 handle_inferior_event exits. It takes care of any last bits of
3228 housekeeping, and sets the all-important wait_some_more flag. */
3231 prepare_to_wait (struct execution_control_state *ecs)
3233 if (ecs->infwait_state == infwait_normal_state)
3235 overlay_cache_invalid = 1;
3237 /* We have to invalidate the registers BEFORE calling
3238 target_wait because they can be loaded from the target while
3239 in target_wait. This makes remote debugging a bit more
3240 efficient for those targets that provide critical registers
3241 as part of their normal status mechanism. */
3243 registers_changed ();
3244 ecs->waiton_ptid = pid_to_ptid (-1);
3245 ecs->wp = &(ecs->ws);
3247 /* This is the old end of the while loop. Let everybody know we
3248 want to wait for the inferior some more and get called again
3250 ecs->wait_some_more = 1;
3253 /* Print why the inferior has stopped. We always print something when
3254 the inferior exits, or receives a signal. The rest of the cases are
3255 dealt with later on in normal_stop() and print_it_typical(). Ideally
3256 there should be a call to this function from handle_inferior_event()
3257 each time stop_stepping() is called.*/
3259 print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
3261 switch (stop_reason)
3264 /* We don't deal with these cases from handle_inferior_event()
3267 case END_STEPPING_RANGE:
3268 /* We are done with a step/next/si/ni command. */
3269 /* For now print nothing. */
3270 /* Print a message only if not in the middle of doing a "step n"
3271 operation for n > 1 */
3272 if (!step_multi || !stop_step)
3273 if (ui_out_is_mi_like_p (uiout))
3274 ui_out_field_string (uiout, "reason", "end-stepping-range");
3276 case BREAKPOINT_HIT:
3277 /* We found a breakpoint. */
3278 /* For now print nothing. */
3281 /* The inferior was terminated by a signal. */
3282 annotate_signalled ();
3283 if (ui_out_is_mi_like_p (uiout))
3284 ui_out_field_string (uiout, "reason", "exited-signalled");
3285 ui_out_text (uiout, "\nProgram terminated with signal ");
3286 annotate_signal_name ();
3287 ui_out_field_string (uiout, "signal-name",
3288 target_signal_to_name (stop_info));
3289 annotate_signal_name_end ();
3290 ui_out_text (uiout, ", ");
3291 annotate_signal_string ();
3292 ui_out_field_string (uiout, "signal-meaning",
3293 target_signal_to_string (stop_info));
3294 annotate_signal_string_end ();
3295 ui_out_text (uiout, ".\n");
3296 ui_out_text (uiout, "The program no longer exists.\n");
3299 /* The inferior program is finished. */
3300 annotate_exited (stop_info);
3303 if (ui_out_is_mi_like_p (uiout))
3304 ui_out_field_string (uiout, "reason", "exited");
3305 ui_out_text (uiout, "\nProgram exited with code ");
3306 ui_out_field_fmt (uiout, "exit-code", "0%o",
3307 (unsigned int) stop_info);
3308 ui_out_text (uiout, ".\n");
3312 if (ui_out_is_mi_like_p (uiout))
3313 ui_out_field_string (uiout, "reason", "exited-normally");
3314 ui_out_text (uiout, "\nProgram exited normally.\n");
3317 case SIGNAL_RECEIVED:
3318 /* Signal received. The signal table tells us to print about
3321 ui_out_text (uiout, "\nProgram received signal ");
3322 annotate_signal_name ();
3323 if (ui_out_is_mi_like_p (uiout))
3324 ui_out_field_string (uiout, "reason", "signal-received");
3325 ui_out_field_string (uiout, "signal-name",
3326 target_signal_to_name (stop_info));
3327 annotate_signal_name_end ();
3328 ui_out_text (uiout, ", ");
3329 annotate_signal_string ();
3330 ui_out_field_string (uiout, "signal-meaning",
3331 target_signal_to_string (stop_info));
3332 annotate_signal_string_end ();
3333 ui_out_text (uiout, ".\n");
3336 internal_error (__FILE__, __LINE__,
3337 "print_stop_reason: unrecognized enum value");
3343 /* Here to return control to GDB when the inferior stops for real.
3344 Print appropriate messages, remove breakpoints, give terminal our modes.
3346 STOP_PRINT_FRAME nonzero means print the executing frame
3347 (pc, function, args, file, line number and line text).
3348 BREAKPOINTS_FAILED nonzero means stop was due to error
3349 attempting to insert breakpoints. */
3354 /* As with the notification of thread events, we want to delay
3355 notifying the user that we've switched thread context until
3356 the inferior actually stops.
3358 (Note that there's no point in saying anything if the inferior
3360 if (!ptid_equal (previous_inferior_ptid, inferior_ptid)
3361 && target_has_execution)
3363 target_terminal_ours_for_output ();
3364 printf_filtered ("[Switching to %s]\n",
3365 target_pid_or_tid_to_str (inferior_ptid));
3366 previous_inferior_ptid = inferior_ptid;
3369 /* Make sure that the current_frame's pc is correct. This
3370 is a correction for setting up the frame info before doing
3371 DECR_PC_AFTER_BREAK */
3372 if (target_has_execution && get_current_frame ())
3373 (get_current_frame ())->pc = read_pc ();
3375 if (target_has_execution && breakpoints_inserted)
3377 if (remove_breakpoints ())
3379 target_terminal_ours_for_output ();
3380 printf_filtered ("Cannot remove breakpoints because ");
3381 printf_filtered ("program is no longer writable.\n");
3382 printf_filtered ("It might be running in another process.\n");
3383 printf_filtered ("Further execution is probably impossible.\n");
3386 breakpoints_inserted = 0;
3388 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3389 Delete any breakpoint that is to be deleted at the next stop. */
3391 breakpoint_auto_delete (stop_bpstat);
3393 /* If an auto-display called a function and that got a signal,
3394 delete that auto-display to avoid an infinite recursion. */
3396 if (stopped_by_random_signal)
3397 disable_current_display ();
3399 /* Don't print a message if in the middle of doing a "step n"
3400 operation for n > 1 */
3401 if (step_multi && stop_step)
3404 target_terminal_ours ();
3406 /* Look up the hook_stop and run it (CLI internally handles problem
3407 of stop_command's pre-hook not existing). */
3409 catch_errors (hook_stop_stub, stop_command,
3410 "Error while running hook_stop:\n", RETURN_MASK_ALL);
3412 if (!target_has_stack)
3418 /* Select innermost stack frame - i.e., current frame is frame 0,
3419 and current location is based on that.
3420 Don't do this on return from a stack dummy routine,
3421 or if the program has exited. */
3423 if (!stop_stack_dummy)
3425 select_frame (get_current_frame ());
3427 /* Print current location without a level number, if
3428 we have changed functions or hit a breakpoint.
3429 Print source line if we have one.
3430 bpstat_print() contains the logic deciding in detail
3431 what to print, based on the event(s) that just occurred. */
3433 if (stop_print_frame && selected_frame)
3437 int do_frame_printing = 1;
3439 bpstat_ret = bpstat_print (stop_bpstat);
3444 && step_frame_address == FRAME_FP (get_current_frame ())
3445 && step_start_function == find_pc_function (stop_pc))
3446 source_flag = SRC_LINE; /* finished step, just print source line */
3448 source_flag = SRC_AND_LOC; /* print location and source line */
3450 case PRINT_SRC_AND_LOC:
3451 source_flag = SRC_AND_LOC; /* print location and source line */
3453 case PRINT_SRC_ONLY:
3454 source_flag = SRC_LINE;
3457 source_flag = SRC_LINE; /* something bogus */
3458 do_frame_printing = 0;
3461 internal_error (__FILE__, __LINE__, "Unknown value.");
3463 /* For mi, have the same behavior every time we stop:
3464 print everything but the source line. */
3465 if (ui_out_is_mi_like_p (uiout))
3466 source_flag = LOC_AND_ADDRESS;
3468 if (ui_out_is_mi_like_p (uiout))
3469 ui_out_field_int (uiout, "thread-id",
3470 pid_to_thread_id (inferior_ptid));
3471 /* The behavior of this routine with respect to the source
3473 SRC_LINE: Print only source line
3474 LOCATION: Print only location
3475 SRC_AND_LOC: Print location and source line */
3476 if (do_frame_printing)
3477 show_and_print_stack_frame (selected_frame, -1, source_flag);
3479 /* Display the auto-display expressions. */
3484 /* Save the function value return registers, if we care.
3485 We might be about to restore their previous contents. */
3486 if (proceed_to_finish)
3487 /* NB: The copy goes through to the target picking up the value of
3488 all the registers. */
3489 regcache_cpy (stop_registers, current_regcache);
3491 if (stop_stack_dummy)
3493 /* Pop the empty frame that contains the stack dummy.
3494 POP_FRAME ends with a setting of the current frame, so we
3495 can use that next. */
3497 /* Set stop_pc to what it was before we called the function.
3498 Can't rely on restore_inferior_status because that only gets
3499 called if we don't stop in the called function. */
3500 stop_pc = read_pc ();
3501 select_frame (get_current_frame ());
3505 annotate_stopped ();
3509 hook_stop_stub (void *cmd)
3511 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
3516 signal_stop_state (int signo)
3518 return signal_stop[signo];
3522 signal_print_state (int signo)
3524 return signal_print[signo];
3528 signal_pass_state (int signo)
3530 return signal_program[signo];
3534 signal_stop_update (signo, state)
3538 int ret = signal_stop[signo];
3539 signal_stop[signo] = state;
3544 signal_print_update (signo, state)
3548 int ret = signal_print[signo];
3549 signal_print[signo] = state;
3554 signal_pass_update (signo, state)
3558 int ret = signal_program[signo];
3559 signal_program[signo] = state;
3564 sig_print_header (void)
3567 Signal Stop\tPrint\tPass to program\tDescription\n");
3571 sig_print_info (enum target_signal oursig)
3573 char *name = target_signal_to_name (oursig);
3574 int name_padding = 13 - strlen (name);
3576 if (name_padding <= 0)
3579 printf_filtered ("%s", name);
3580 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
3581 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
3582 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
3583 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
3584 printf_filtered ("%s\n", target_signal_to_string (oursig));
3587 /* Specify how various signals in the inferior should be handled. */
3590 handle_command (char *args, int from_tty)
3593 int digits, wordlen;
3594 int sigfirst, signum, siglast;
3595 enum target_signal oursig;
3598 unsigned char *sigs;
3599 struct cleanup *old_chain;
3603 error_no_arg ("signal to handle");
3606 /* Allocate and zero an array of flags for which signals to handle. */
3608 nsigs = (int) TARGET_SIGNAL_LAST;
3609 sigs = (unsigned char *) alloca (nsigs);
3610 memset (sigs, 0, nsigs);
3612 /* Break the command line up into args. */
3614 argv = buildargv (args);
3619 old_chain = make_cleanup_freeargv (argv);
3621 /* Walk through the args, looking for signal oursigs, signal names, and
3622 actions. Signal numbers and signal names may be interspersed with
3623 actions, with the actions being performed for all signals cumulatively
3624 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
3626 while (*argv != NULL)
3628 wordlen = strlen (*argv);
3629 for (digits = 0; isdigit ((*argv)[digits]); digits++)
3633 sigfirst = siglast = -1;
3635 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
3637 /* Apply action to all signals except those used by the
3638 debugger. Silently skip those. */
3641 siglast = nsigs - 1;
3643 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
3645 SET_SIGS (nsigs, sigs, signal_stop);
3646 SET_SIGS (nsigs, sigs, signal_print);
3648 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
3650 UNSET_SIGS (nsigs, sigs, signal_program);
3652 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
3654 SET_SIGS (nsigs, sigs, signal_print);
3656 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
3658 SET_SIGS (nsigs, sigs, signal_program);
3660 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
3662 UNSET_SIGS (nsigs, sigs, signal_stop);
3664 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
3666 SET_SIGS (nsigs, sigs, signal_program);
3668 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
3670 UNSET_SIGS (nsigs, sigs, signal_print);
3671 UNSET_SIGS (nsigs, sigs, signal_stop);
3673 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
3675 UNSET_SIGS (nsigs, sigs, signal_program);
3677 else if (digits > 0)
3679 /* It is numeric. The numeric signal refers to our own
3680 internal signal numbering from target.h, not to host/target
3681 signal number. This is a feature; users really should be
3682 using symbolic names anyway, and the common ones like
3683 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
3685 sigfirst = siglast = (int)
3686 target_signal_from_command (atoi (*argv));
3687 if ((*argv)[digits] == '-')
3690 target_signal_from_command (atoi ((*argv) + digits + 1));
3692 if (sigfirst > siglast)
3694 /* Bet he didn't figure we'd think of this case... */
3702 oursig = target_signal_from_name (*argv);
3703 if (oursig != TARGET_SIGNAL_UNKNOWN)
3705 sigfirst = siglast = (int) oursig;
3709 /* Not a number and not a recognized flag word => complain. */
3710 error ("Unrecognized or ambiguous flag word: \"%s\".", *argv);
3714 /* If any signal numbers or symbol names were found, set flags for
3715 which signals to apply actions to. */
3717 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
3719 switch ((enum target_signal) signum)
3721 case TARGET_SIGNAL_TRAP:
3722 case TARGET_SIGNAL_INT:
3723 if (!allsigs && !sigs[signum])
3725 if (query ("%s is used by the debugger.\n\
3726 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal) signum)))
3732 printf_unfiltered ("Not confirmed, unchanged.\n");
3733 gdb_flush (gdb_stdout);
3737 case TARGET_SIGNAL_0:
3738 case TARGET_SIGNAL_DEFAULT:
3739 case TARGET_SIGNAL_UNKNOWN:
3740 /* Make sure that "all" doesn't print these. */
3751 target_notice_signals (inferior_ptid);
3755 /* Show the results. */
3756 sig_print_header ();
3757 for (signum = 0; signum < nsigs; signum++)
3761 sig_print_info (signum);
3766 do_cleanups (old_chain);
3770 xdb_handle_command (char *args, int from_tty)
3773 struct cleanup *old_chain;
3775 /* Break the command line up into args. */
3777 argv = buildargv (args);
3782 old_chain = make_cleanup_freeargv (argv);
3783 if (argv[1] != (char *) NULL)
3788 bufLen = strlen (argv[0]) + 20;
3789 argBuf = (char *) xmalloc (bufLen);
3793 enum target_signal oursig;
3795 oursig = target_signal_from_name (argv[0]);
3796 memset (argBuf, 0, bufLen);
3797 if (strcmp (argv[1], "Q") == 0)
3798 sprintf (argBuf, "%s %s", argv[0], "noprint");
3801 if (strcmp (argv[1], "s") == 0)
3803 if (!signal_stop[oursig])
3804 sprintf (argBuf, "%s %s", argv[0], "stop");
3806 sprintf (argBuf, "%s %s", argv[0], "nostop");
3808 else if (strcmp (argv[1], "i") == 0)
3810 if (!signal_program[oursig])
3811 sprintf (argBuf, "%s %s", argv[0], "pass");
3813 sprintf (argBuf, "%s %s", argv[0], "nopass");
3815 else if (strcmp (argv[1], "r") == 0)
3817 if (!signal_print[oursig])
3818 sprintf (argBuf, "%s %s", argv[0], "print");
3820 sprintf (argBuf, "%s %s", argv[0], "noprint");
3826 handle_command (argBuf, from_tty);
3828 printf_filtered ("Invalid signal handling flag.\n");
3833 do_cleanups (old_chain);
3836 /* Print current contents of the tables set by the handle command.
3837 It is possible we should just be printing signals actually used
3838 by the current target (but for things to work right when switching
3839 targets, all signals should be in the signal tables). */
3842 signals_info (char *signum_exp, int from_tty)
3844 enum target_signal oursig;
3845 sig_print_header ();
3849 /* First see if this is a symbol name. */
3850 oursig = target_signal_from_name (signum_exp);
3851 if (oursig == TARGET_SIGNAL_UNKNOWN)
3853 /* No, try numeric. */
3855 target_signal_from_command (parse_and_eval_long (signum_exp));
3857 sig_print_info (oursig);
3861 printf_filtered ("\n");
3862 /* These ugly casts brought to you by the native VAX compiler. */
3863 for (oursig = TARGET_SIGNAL_FIRST;
3864 (int) oursig < (int) TARGET_SIGNAL_LAST;
3865 oursig = (enum target_signal) ((int) oursig + 1))
3869 if (oursig != TARGET_SIGNAL_UNKNOWN
3870 && oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0)
3871 sig_print_info (oursig);
3874 printf_filtered ("\nUse the \"handle\" command to change these tables.\n");
3877 struct inferior_status
3879 enum target_signal stop_signal;
3883 int stop_stack_dummy;
3884 int stopped_by_random_signal;
3886 CORE_ADDR step_range_start;
3887 CORE_ADDR step_range_end;
3888 CORE_ADDR step_frame_address;
3889 enum step_over_calls_kind step_over_calls;
3890 CORE_ADDR step_resume_break_address;
3891 int stop_after_trap;
3892 int stop_soon_quietly;
3893 struct regcache *stop_registers;
3895 /* These are here because if call_function_by_hand has written some
3896 registers and then decides to call error(), we better not have changed
3898 struct regcache *registers;
3900 /* A frame unique identifier. */
3901 struct frame_id selected_frame_id;
3903 int breakpoint_proceeded;
3904 int restore_stack_info;
3905 int proceed_to_finish;
3909 write_inferior_status_register (struct inferior_status *inf_status, int regno,
3912 int size = REGISTER_RAW_SIZE (regno);
3913 void *buf = alloca (size);
3914 store_signed_integer (buf, size, val);
3915 regcache_raw_write (inf_status->registers, regno, buf);
3918 /* Save all of the information associated with the inferior<==>gdb
3919 connection. INF_STATUS is a pointer to a "struct inferior_status"
3920 (defined in inferior.h). */
3922 struct inferior_status *
3923 save_inferior_status (int restore_stack_info)
3925 struct inferior_status *inf_status = XMALLOC (struct inferior_status);
3927 inf_status->stop_signal = stop_signal;
3928 inf_status->stop_pc = stop_pc;
3929 inf_status->stop_step = stop_step;
3930 inf_status->stop_stack_dummy = stop_stack_dummy;
3931 inf_status->stopped_by_random_signal = stopped_by_random_signal;
3932 inf_status->trap_expected = trap_expected;
3933 inf_status->step_range_start = step_range_start;
3934 inf_status->step_range_end = step_range_end;
3935 inf_status->step_frame_address = step_frame_address;
3936 inf_status->step_over_calls = step_over_calls;
3937 inf_status->stop_after_trap = stop_after_trap;
3938 inf_status->stop_soon_quietly = stop_soon_quietly;
3939 /* Save original bpstat chain here; replace it with copy of chain.
3940 If caller's caller is walking the chain, they'll be happier if we
3941 hand them back the original chain when restore_inferior_status is
3943 inf_status->stop_bpstat = stop_bpstat;
3944 stop_bpstat = bpstat_copy (stop_bpstat);
3945 inf_status->breakpoint_proceeded = breakpoint_proceeded;
3946 inf_status->restore_stack_info = restore_stack_info;
3947 inf_status->proceed_to_finish = proceed_to_finish;
3949 inf_status->stop_registers = regcache_dup_no_passthrough (stop_registers);
3951 inf_status->registers = regcache_dup (current_regcache);
3953 get_frame_id (selected_frame, &inf_status->selected_frame_id);
3958 restore_selected_frame (void *args)
3960 struct frame_id *fid = (struct frame_id *) args;
3961 struct frame_info *frame;
3963 frame = frame_find_by_id (*fid);
3965 /* If inf_status->selected_frame_address is NULL, there was no
3966 previously selected frame. */
3969 warning ("Unable to restore previously selected frame.\n");
3973 select_frame (frame);
3979 restore_inferior_status (struct inferior_status *inf_status)
3981 stop_signal = inf_status->stop_signal;
3982 stop_pc = inf_status->stop_pc;
3983 stop_step = inf_status->stop_step;
3984 stop_stack_dummy = inf_status->stop_stack_dummy;
3985 stopped_by_random_signal = inf_status->stopped_by_random_signal;
3986 trap_expected = inf_status->trap_expected;
3987 step_range_start = inf_status->step_range_start;
3988 step_range_end = inf_status->step_range_end;
3989 step_frame_address = inf_status->step_frame_address;
3990 step_over_calls = inf_status->step_over_calls;
3991 stop_after_trap = inf_status->stop_after_trap;
3992 stop_soon_quietly = inf_status->stop_soon_quietly;
3993 bpstat_clear (&stop_bpstat);
3994 stop_bpstat = inf_status->stop_bpstat;
3995 breakpoint_proceeded = inf_status->breakpoint_proceeded;
3996 proceed_to_finish = inf_status->proceed_to_finish;
3998 /* FIXME: Is the restore of stop_registers always needed. */
3999 regcache_xfree (stop_registers);
4000 stop_registers = inf_status->stop_registers;
4002 /* The inferior can be gone if the user types "print exit(0)"
4003 (and perhaps other times). */
4004 if (target_has_execution)
4005 /* NB: The register write goes through to the target. */
4006 regcache_cpy (current_regcache, inf_status->registers);
4007 regcache_xfree (inf_status->registers);
4009 /* FIXME: If we are being called after stopping in a function which
4010 is called from gdb, we should not be trying to restore the
4011 selected frame; it just prints a spurious error message (The
4012 message is useful, however, in detecting bugs in gdb (like if gdb
4013 clobbers the stack)). In fact, should we be restoring the
4014 inferior status at all in that case? . */
4016 if (target_has_stack && inf_status->restore_stack_info)
4018 /* The point of catch_errors is that if the stack is clobbered,
4019 walking the stack might encounter a garbage pointer and
4020 error() trying to dereference it. */
4022 (restore_selected_frame, &inf_status->selected_frame_id,
4023 "Unable to restore previously selected frame:\n",
4024 RETURN_MASK_ERROR) == 0)
4025 /* Error in restoring the selected frame. Select the innermost
4027 select_frame (get_current_frame ());
4035 do_restore_inferior_status_cleanup (void *sts)
4037 restore_inferior_status (sts);
4041 make_cleanup_restore_inferior_status (struct inferior_status *inf_status)
4043 return make_cleanup (do_restore_inferior_status_cleanup, inf_status);
4047 discard_inferior_status (struct inferior_status *inf_status)
4049 /* See save_inferior_status for info on stop_bpstat. */
4050 bpstat_clear (&inf_status->stop_bpstat);
4051 regcache_xfree (inf_status->registers);
4052 regcache_xfree (inf_status->stop_registers);
4056 /* Oft used ptids */
4058 ptid_t minus_one_ptid;
4060 /* Create a ptid given the necessary PID, LWP, and TID components. */
4063 ptid_build (int pid, long lwp, long tid)
4073 /* Create a ptid from just a pid. */
4076 pid_to_ptid (int pid)
4078 return ptid_build (pid, 0, 0);
4081 /* Fetch the pid (process id) component from a ptid. */
4084 ptid_get_pid (ptid_t ptid)
4089 /* Fetch the lwp (lightweight process) component from a ptid. */
4092 ptid_get_lwp (ptid_t ptid)
4097 /* Fetch the tid (thread id) component from a ptid. */
4100 ptid_get_tid (ptid_t ptid)
4105 /* ptid_equal() is used to test equality of two ptids. */
4108 ptid_equal (ptid_t ptid1, ptid_t ptid2)
4110 return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp
4111 && ptid1.tid == ptid2.tid);
4114 /* restore_inferior_ptid() will be used by the cleanup machinery
4115 to restore the inferior_ptid value saved in a call to
4116 save_inferior_ptid(). */
4119 restore_inferior_ptid (void *arg)
4121 ptid_t *saved_ptid_ptr = arg;
4122 inferior_ptid = *saved_ptid_ptr;
4126 /* Save the value of inferior_ptid so that it may be restored by a
4127 later call to do_cleanups(). Returns the struct cleanup pointer
4128 needed for later doing the cleanup. */
4131 save_inferior_ptid (void)
4133 ptid_t *saved_ptid_ptr;
4135 saved_ptid_ptr = xmalloc (sizeof (ptid_t));
4136 *saved_ptid_ptr = inferior_ptid;
4137 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
4144 stop_registers = regcache_xmalloc (current_gdbarch);
4148 _initialize_infrun (void)
4151 register int numsigs;
4152 struct cmd_list_element *c;
4154 register_gdbarch_swap (&stop_registers, sizeof (stop_registers), NULL);
4155 register_gdbarch_swap (NULL, 0, build_infrun);
4157 add_info ("signals", signals_info,
4158 "What debugger does when program gets various signals.\n\
4159 Specify a signal as argument to print info on that signal only.");
4160 add_info_alias ("handle", "signals", 0);
4162 add_com ("handle", class_run, handle_command,
4163 concat ("Specify how to handle a signal.\n\
4164 Args are signals and actions to apply to those signals.\n\
4165 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4166 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4167 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4168 The special arg \"all\" is recognized to mean all signals except those\n\
4169 used by the debugger, typically SIGTRAP and SIGINT.\n", "Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4170 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4171 Stop means reenter debugger if this signal happens (implies print).\n\
4172 Print means print a message if this signal happens.\n\
4173 Pass means let program see this signal; otherwise program doesn't know.\n\
4174 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4175 Pass and Stop may be combined.", NULL));
4178 add_com ("lz", class_info, signals_info,
4179 "What debugger does when program gets various signals.\n\
4180 Specify a signal as argument to print info on that signal only.");
4181 add_com ("z", class_run, xdb_handle_command,
4182 concat ("Specify how to handle a signal.\n\
4183 Args are signals and actions to apply to those signals.\n\
4184 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4185 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4186 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4187 The special arg \"all\" is recognized to mean all signals except those\n\
4188 used by the debugger, typically SIGTRAP and SIGINT.\n", "Recognized actions include \"s\" (toggles between stop and nostop), \n\
4189 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4190 nopass), \"Q\" (noprint)\n\
4191 Stop means reenter debugger if this signal happens (implies print).\n\
4192 Print means print a message if this signal happens.\n\
4193 Pass means let program see this signal; otherwise program doesn't know.\n\
4194 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4195 Pass and Stop may be combined.", NULL));
4200 add_cmd ("stop", class_obscure, not_just_help_class_command, "There is no `stop' command, but you can set a hook on `stop'.\n\
4201 This allows you to set a list of commands to be run each time execution\n\
4202 of the program stops.", &cmdlist);
4204 numsigs = (int) TARGET_SIGNAL_LAST;
4205 signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
4206 signal_print = (unsigned char *)
4207 xmalloc (sizeof (signal_print[0]) * numsigs);
4208 signal_program = (unsigned char *)
4209 xmalloc (sizeof (signal_program[0]) * numsigs);
4210 for (i = 0; i < numsigs; i++)
4213 signal_print[i] = 1;
4214 signal_program[i] = 1;
4217 /* Signals caused by debugger's own actions
4218 should not be given to the program afterwards. */
4219 signal_program[TARGET_SIGNAL_TRAP] = 0;
4220 signal_program[TARGET_SIGNAL_INT] = 0;
4222 /* Signals that are not errors should not normally enter the debugger. */
4223 signal_stop[TARGET_SIGNAL_ALRM] = 0;
4224 signal_print[TARGET_SIGNAL_ALRM] = 0;
4225 signal_stop[TARGET_SIGNAL_VTALRM] = 0;
4226 signal_print[TARGET_SIGNAL_VTALRM] = 0;
4227 signal_stop[TARGET_SIGNAL_PROF] = 0;
4228 signal_print[TARGET_SIGNAL_PROF] = 0;
4229 signal_stop[TARGET_SIGNAL_CHLD] = 0;
4230 signal_print[TARGET_SIGNAL_CHLD] = 0;
4231 signal_stop[TARGET_SIGNAL_IO] = 0;
4232 signal_print[TARGET_SIGNAL_IO] = 0;
4233 signal_stop[TARGET_SIGNAL_POLL] = 0;
4234 signal_print[TARGET_SIGNAL_POLL] = 0;
4235 signal_stop[TARGET_SIGNAL_URG] = 0;
4236 signal_print[TARGET_SIGNAL_URG] = 0;
4237 signal_stop[TARGET_SIGNAL_WINCH] = 0;
4238 signal_print[TARGET_SIGNAL_WINCH] = 0;
4240 /* These signals are used internally by user-level thread
4241 implementations. (See signal(5) on Solaris.) Like the above
4242 signals, a healthy program receives and handles them as part of
4243 its normal operation. */
4244 signal_stop[TARGET_SIGNAL_LWP] = 0;
4245 signal_print[TARGET_SIGNAL_LWP] = 0;
4246 signal_stop[TARGET_SIGNAL_WAITING] = 0;
4247 signal_print[TARGET_SIGNAL_WAITING] = 0;
4248 signal_stop[TARGET_SIGNAL_CANCEL] = 0;
4249 signal_print[TARGET_SIGNAL_CANCEL] = 0;
4253 (add_set_cmd ("stop-on-solib-events", class_support, var_zinteger,
4254 (char *) &stop_on_solib_events,
4255 "Set stopping for shared library events.\n\
4256 If nonzero, gdb will give control to the user when the dynamic linker\n\
4257 notifies gdb of shared library events. The most common event of interest\n\
4258 to the user would be loading/unloading of a new library.\n", &setlist), &showlist);
4261 c = add_set_enum_cmd ("follow-fork-mode",
4263 follow_fork_mode_kind_names, &follow_fork_mode_string,
4264 /* ??rehrauer: The "both" option is broken, by what may be a 10.20
4265 kernel problem. It's also not terribly useful without a GUI to
4266 help the user drive two debuggers. So for now, I'm disabling
4267 the "both" option. */
4268 /* "Set debugger response to a program call of fork \
4270 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4271 parent - the original process is debugged after a fork\n\
4272 child - the new process is debugged after a fork\n\
4273 both - both the parent and child are debugged after a fork\n\
4274 ask - the debugger will ask for one of the above choices\n\
4275 For \"both\", another copy of the debugger will be started to follow\n\
4276 the new child process. The original debugger will continue to follow\n\
4277 the original parent process. To distinguish their prompts, the\n\
4278 debugger copy's prompt will be changed.\n\
4279 For \"parent\" or \"child\", the unfollowed process will run free.\n\
4280 By default, the debugger will follow the parent process.",
4282 "Set debugger response to a program call of fork \
4284 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4285 parent - the original process is debugged after a fork\n\
4286 child - the new process is debugged after a fork\n\
4287 ask - the debugger will ask for one of the above choices\n\
4288 For \"parent\" or \"child\", the unfollowed process will run free.\n\
4289 By default, the debugger will follow the parent process.", &setlist);
4290 add_show_from_set (c, &showlist);
4292 c = add_set_enum_cmd ("scheduler-locking", class_run, scheduler_enums, /* array of string names */
4293 &scheduler_mode, /* current mode */
4294 "Set mode for locking scheduler during execution.\n\
4295 off == no locking (threads may preempt at any time)\n\
4296 on == full locking (no thread except the current thread may run)\n\
4297 step == scheduler locked during every single-step operation.\n\
4298 In this mode, no other thread may run during a step command.\n\
4299 Other threads may run while stepping over a function call ('next').", &setlist);
4301 set_cmd_sfunc (c, set_schedlock_func); /* traps on target vector */
4302 add_show_from_set (c, &showlist);
4304 c = add_set_cmd ("step-mode", class_run,
4305 var_boolean, (char *) &step_stop_if_no_debug,
4306 "Set mode of the step operation. When set, doing a step over a\n\
4307 function without debug line information will stop at the first\n\
4308 instruction of that function. Otherwise, the function is skipped and\n\
4309 the step command stops at a different source line.", &setlist);
4310 add_show_from_set (c, &showlist);
4312 /* ptid initializations */
4313 null_ptid = ptid_build (0, 0, 0);
4314 minus_one_ptid = ptid_build (-1, 0, 0);
4315 inferior_ptid = null_ptid;
4316 target_last_wait_ptid = minus_one_ptid;