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 /* In some shared library schemes, the return path from a shared library
177 call may need to go through a trampoline too. */
179 #ifndef IN_SOLIB_RETURN_TRAMPOLINE
180 #define IN_SOLIB_RETURN_TRAMPOLINE(pc,name) 0
183 /* This function returns TRUE if pc is the address of an instruction
184 that lies within the dynamic linker (such as the event hook, or the
187 This function must be used only when a dynamic linker event has
188 been caught, and the inferior is being stepped out of the hook, or
189 undefined results are guaranteed. */
191 #ifndef SOLIB_IN_DYNAMIC_LINKER
192 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
195 /* On MIPS16, a function that returns a floating point value may call
196 a library helper function to copy the return value to a floating point
197 register. The IGNORE_HELPER_CALL macro returns non-zero if we
198 should ignore (i.e. step over) this function call. */
199 #ifndef IGNORE_HELPER_CALL
200 #define IGNORE_HELPER_CALL(pc) 0
203 /* On some systems, the PC may be left pointing at an instruction that won't
204 actually be executed. This is usually indicated by a bit in the PSW. If
205 we find ourselves in such a state, then we step the target beyond the
206 nullified instruction before returning control to the user so as to avoid
209 #ifndef INSTRUCTION_NULLIFIED
210 #define INSTRUCTION_NULLIFIED 0
213 /* We can't step off a permanent breakpoint in the ordinary way, because we
214 can't remove it. Instead, we have to advance the PC to the next
215 instruction. This macro should expand to a pointer to a function that
216 does that, or zero if we have no such function. If we don't have a
217 definition for it, we have to report an error. */
218 #ifndef SKIP_PERMANENT_BREAKPOINT
219 #define SKIP_PERMANENT_BREAKPOINT (default_skip_permanent_breakpoint)
221 default_skip_permanent_breakpoint (void)
224 The program is stopped at a permanent breakpoint, but GDB does not know\n\
225 how to step past a permanent breakpoint on this architecture. Try using\n\
226 a command like `return' or `jump' to continue execution.");
231 /* Convert the #defines into values. This is temporary until wfi control
232 flow is completely sorted out. */
234 #ifndef HAVE_STEPPABLE_WATCHPOINT
235 #define HAVE_STEPPABLE_WATCHPOINT 0
237 #undef HAVE_STEPPABLE_WATCHPOINT
238 #define HAVE_STEPPABLE_WATCHPOINT 1
241 #ifndef HAVE_NONSTEPPABLE_WATCHPOINT
242 #define HAVE_NONSTEPPABLE_WATCHPOINT 0
244 #undef HAVE_NONSTEPPABLE_WATCHPOINT
245 #define HAVE_NONSTEPPABLE_WATCHPOINT 1
248 #ifndef HAVE_CONTINUABLE_WATCHPOINT
249 #define HAVE_CONTINUABLE_WATCHPOINT 0
251 #undef HAVE_CONTINUABLE_WATCHPOINT
252 #define HAVE_CONTINUABLE_WATCHPOINT 1
255 #ifndef CANNOT_STEP_HW_WATCHPOINTS
256 #define CANNOT_STEP_HW_WATCHPOINTS 0
258 #undef CANNOT_STEP_HW_WATCHPOINTS
259 #define CANNOT_STEP_HW_WATCHPOINTS 1
262 /* Tables of how to react to signals; the user sets them. */
264 static unsigned char *signal_stop;
265 static unsigned char *signal_print;
266 static unsigned char *signal_program;
268 #define SET_SIGS(nsigs,sigs,flags) \
270 int signum = (nsigs); \
271 while (signum-- > 0) \
272 if ((sigs)[signum]) \
273 (flags)[signum] = 1; \
276 #define UNSET_SIGS(nsigs,sigs,flags) \
278 int signum = (nsigs); \
279 while (signum-- > 0) \
280 if ((sigs)[signum]) \
281 (flags)[signum] = 0; \
284 /* Value to pass to target_resume() to cause all threads to resume */
286 #define RESUME_ALL (pid_to_ptid (-1))
288 /* Command list pointer for the "stop" placeholder. */
290 static struct cmd_list_element *stop_command;
292 /* Nonzero if breakpoints are now inserted in the inferior. */
294 static int breakpoints_inserted;
296 /* Function inferior was in as of last step command. */
298 static struct symbol *step_start_function;
300 /* Nonzero if we are expecting a trace trap and should proceed from it. */
302 static int trap_expected;
305 /* Nonzero if we want to give control to the user when we're notified
306 of shared library events by the dynamic linker. */
307 static int stop_on_solib_events;
311 /* Nonzero if the next time we try to continue the inferior, it will
312 step one instruction and generate a spurious trace trap.
313 This is used to compensate for a bug in HP-UX. */
315 static int trap_expected_after_continue;
318 /* Nonzero means expecting a trace trap
319 and should stop the inferior and return silently when it happens. */
323 /* Nonzero means expecting a trap and caller will handle it themselves.
324 It is used after attach, due to attaching to a process;
325 when running in the shell before the child program has been exec'd;
326 and when running some kinds of remote stuff (FIXME?). */
328 int stop_soon_quietly;
330 /* Nonzero if proceed is being used for a "finish" command or a similar
331 situation when stop_registers should be saved. */
333 int proceed_to_finish;
335 /* Save register contents here when about to pop a stack dummy frame,
336 if-and-only-if proceed_to_finish is set.
337 Thus this contains the return value from the called function (assuming
338 values are returned in a register). */
340 struct regcache *stop_registers;
342 /* Nonzero if program stopped due to error trying to insert breakpoints. */
344 static int breakpoints_failed;
346 /* Nonzero after stop if current stack frame should be printed. */
348 static int stop_print_frame;
350 static struct breakpoint *step_resume_breakpoint = NULL;
351 static struct breakpoint *through_sigtramp_breakpoint = NULL;
353 /* On some platforms (e.g., HP-UX), hardware watchpoints have bad
354 interactions with an inferior that is running a kernel function
355 (aka, a system call or "syscall"). wait_for_inferior therefore
356 may have a need to know when the inferior is in a syscall. This
357 is a count of the number of inferior threads which are known to
358 currently be running in a syscall. */
359 static int number_of_threads_in_syscalls;
361 /* This is a cached copy of the pid/waitstatus of the last event
362 returned by target_wait()/target_wait_hook(). This information is
363 returned by get_last_target_status(). */
364 static ptid_t target_last_wait_ptid;
365 static struct target_waitstatus target_last_waitstatus;
367 /* This is used to remember when a fork, vfork or exec event
368 was caught by a catchpoint, and thus the event is to be
369 followed at the next resume of the inferior, and not
373 enum target_waitkind kind;
383 char *execd_pathname;
387 /* Some platforms don't allow us to do anything meaningful with a
388 vforked child until it has exec'd. Vforked processes on such
389 platforms can only be followed after they've exec'd.
391 When this is set to 0, a vfork can be immediately followed,
392 and an exec can be followed merely as an exec. When this is
393 set to 1, a vfork event has been seen, but cannot be followed
394 until the exec is seen.
396 (In the latter case, inferior_ptid is still the parent of the
397 vfork, and pending_follow.fork_event.child_pid is the child. The
398 appropriate process is followed, according to the setting of
399 follow-fork-mode.) */
400 static int follow_vfork_when_exec;
402 static const char follow_fork_mode_ask[] = "ask";
403 static const char follow_fork_mode_both[] = "both";
404 static const char follow_fork_mode_child[] = "child";
405 static const char follow_fork_mode_parent[] = "parent";
407 static const char *follow_fork_mode_kind_names[] = {
408 follow_fork_mode_ask,
409 /* ??rehrauer: The "both" option is broken, by what may be a 10.20
410 kernel problem. It's also not terribly useful without a GUI to
411 help the user drive two debuggers. So for now, I'm disabling the
413 /* follow_fork_mode_both, */
414 follow_fork_mode_child,
415 follow_fork_mode_parent,
419 static const char *follow_fork_mode_string = follow_fork_mode_parent;
423 follow_inferior_fork (int parent_pid, int child_pid, int has_forked,
426 int followed_parent = 0;
427 int followed_child = 0;
429 /* Which process did the user want us to follow? */
430 const char *follow_mode = follow_fork_mode_string;
432 /* Or, did the user not know, and want us to ask? */
433 if (follow_fork_mode_string == follow_fork_mode_ask)
435 internal_error (__FILE__, __LINE__,
436 "follow_inferior_fork: \"ask\" mode not implemented");
437 /* follow_mode = follow_fork_mode_...; */
440 /* If we're to be following the parent, then detach from child_pid.
441 We're already following the parent, so need do nothing explicit
443 if (follow_mode == follow_fork_mode_parent)
447 /* We're already attached to the parent, by default. */
449 /* Before detaching from the child, remove all breakpoints from
450 it. (This won't actually modify the breakpoint list, but will
451 physically remove the breakpoints from the child.) */
452 if (!has_vforked || !follow_vfork_when_exec)
454 detach_breakpoints (child_pid);
455 #ifdef SOLIB_REMOVE_INFERIOR_HOOK
456 SOLIB_REMOVE_INFERIOR_HOOK (child_pid);
460 /* Detach from the child. */
463 target_require_detach (child_pid, "", 1);
466 /* If we're to be following the child, then attach to it, detach
467 from inferior_ptid, and set inferior_ptid to child_pid. */
468 else if (follow_mode == follow_fork_mode_child)
470 char child_pid_spelling[100]; /* Arbitrary length. */
474 /* Before detaching from the parent, detach all breakpoints from
475 the child. But only if we're forking, or if we follow vforks
476 as soon as they happen. (If we're following vforks only when
477 the child has exec'd, then it's very wrong to try to write
478 back the "shadow contents" of inserted breakpoints now -- they
479 belong to the child's pre-exec'd a.out.) */
480 if (!has_vforked || !follow_vfork_when_exec)
482 detach_breakpoints (child_pid);
485 /* Before detaching from the parent, remove all breakpoints from it. */
486 remove_breakpoints ();
488 /* Also reset the solib inferior hook from the parent. */
489 #ifdef SOLIB_REMOVE_INFERIOR_HOOK
490 SOLIB_REMOVE_INFERIOR_HOOK (PIDGET (inferior_ptid));
493 /* Detach from the parent. */
495 target_detach (NULL, 1);
497 /* Attach to the child. */
498 inferior_ptid = pid_to_ptid (child_pid);
499 sprintf (child_pid_spelling, "%d", child_pid);
502 target_require_attach (child_pid_spelling, 1);
504 /* Was there a step_resume breakpoint? (There was if the user
505 did a "next" at the fork() call.) If so, explicitly reset its
508 step_resumes are a form of bp that are made to be per-thread.
509 Since we created the step_resume bp when the parent process
510 was being debugged, and now are switching to the child process,
511 from the breakpoint package's viewpoint, that's a switch of
512 "threads". We must update the bp's notion of which thread
513 it is for, or it'll be ignored when it triggers... */
514 if (step_resume_breakpoint && (!has_vforked || !follow_vfork_when_exec))
515 breakpoint_re_set_thread (step_resume_breakpoint);
517 /* Reinsert all breakpoints in the child. (The user may've set
518 breakpoints after catching the fork, in which case those
519 actually didn't get set in the child, but only in the parent.) */
520 if (!has_vforked || !follow_vfork_when_exec)
522 breakpoint_re_set ();
523 insert_breakpoints ();
527 /* If we're to be following both parent and child, then fork ourselves,
528 and attach the debugger clone to the child. */
529 else if (follow_mode == follow_fork_mode_both)
531 char pid_suffix[100]; /* Arbitrary length. */
533 /* Clone ourselves to follow the child. This is the end of our
534 involvement with child_pid; our clone will take it from here... */
536 target_clone_and_follow_inferior (child_pid, &followed_child);
537 followed_parent = !followed_child;
539 /* We continue to follow the parent. To help distinguish the two
540 debuggers, though, both we and our clone will reset our prompts. */
541 sprintf (pid_suffix, "[%d] ", PIDGET (inferior_ptid));
542 set_prompt (strcat (get_prompt (), pid_suffix));
545 /* The parent and child of a vfork share the same address space.
546 Also, on some targets the order in which vfork and exec events
547 are received for parent in child requires some delicate handling
550 For instance, on ptrace-based HPUX we receive the child's vfork
551 event first, at which time the parent has been suspended by the
552 OS and is essentially untouchable until the child's exit or second
553 exec event arrives. At that time, the parent's vfork event is
554 delivered to us, and that's when we see and decide how to follow
555 the vfork. But to get to that point, we must continue the child
556 until it execs or exits. To do that smoothly, all breakpoints
557 must be removed from the child, in case there are any set between
558 the vfork() and exec() calls. But removing them from the child
559 also removes them from the parent, due to the shared-address-space
560 nature of a vfork'd parent and child. On HPUX, therefore, we must
561 take care to restore the bp's to the parent before we continue it.
562 Else, it's likely that we may not stop in the expected place. (The
563 worst scenario is when the user tries to step over a vfork() call;
564 the step-resume bp must be restored for the step to properly stop
565 in the parent after the call completes!)
567 Sequence of events, as reported to gdb from HPUX:
569 Parent Child Action for gdb to take
570 -------------------------------------------------------
571 1 VFORK Continue child
577 target_post_follow_vfork (parent_pid,
578 followed_parent, child_pid, followed_child);
581 pending_follow.fork_event.saw_parent_fork = 0;
582 pending_follow.fork_event.saw_child_fork = 0;
586 follow_fork (int parent_pid, int child_pid)
588 follow_inferior_fork (parent_pid, child_pid, 1, 0);
592 /* Forward declaration. */
593 static void follow_exec (int, char *);
596 follow_vfork (int parent_pid, int child_pid)
598 follow_inferior_fork (parent_pid, child_pid, 0, 1);
600 /* Did we follow the child? Had it exec'd before we saw the parent vfork? */
601 if (pending_follow.fork_event.saw_child_exec
602 && (PIDGET (inferior_ptid) == child_pid))
604 pending_follow.fork_event.saw_child_exec = 0;
605 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
606 follow_exec (PIDGET (inferior_ptid), pending_follow.execd_pathname);
607 xfree (pending_follow.execd_pathname);
611 /* EXECD_PATHNAME is assumed to be non-NULL. */
614 follow_exec (int pid, char *execd_pathname)
617 struct target_ops *tgt;
619 if (!may_follow_exec)
622 /* Did this exec() follow a vfork()? If so, we must follow the
623 vfork now too. Do it before following the exec. */
624 if (follow_vfork_when_exec &&
625 (pending_follow.kind == TARGET_WAITKIND_VFORKED))
627 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
628 follow_vfork (PIDGET (inferior_ptid),
629 pending_follow.fork_event.child_pid);
630 follow_vfork_when_exec = 0;
631 saved_pid = PIDGET (inferior_ptid);
633 /* Did we follow the parent? If so, we're done. If we followed
634 the child then we must also follow its exec(). */
635 if (PIDGET (inferior_ptid) == pending_follow.fork_event.parent_pid)
639 /* This is an exec event that we actually wish to pay attention to.
640 Refresh our symbol table to the newly exec'd program, remove any
643 If there are breakpoints, they aren't really inserted now,
644 since the exec() transformed our inferior into a fresh set
647 We want to preserve symbolic breakpoints on the list, since
648 we have hopes that they can be reset after the new a.out's
649 symbol table is read.
651 However, any "raw" breakpoints must be removed from the list
652 (e.g., the solib bp's), since their address is probably invalid
655 And, we DON'T want to call delete_breakpoints() here, since
656 that may write the bp's "shadow contents" (the instruction
657 value that was overwritten witha TRAP instruction). Since
658 we now have a new a.out, those shadow contents aren't valid. */
659 update_breakpoints_after_exec ();
661 /* If there was one, it's gone now. We cannot truly step-to-next
662 statement through an exec(). */
663 step_resume_breakpoint = NULL;
664 step_range_start = 0;
667 /* If there was one, it's gone now. */
668 through_sigtramp_breakpoint = NULL;
670 /* What is this a.out's name? */
671 printf_unfiltered ("Executing new program: %s\n", execd_pathname);
673 /* We've followed the inferior through an exec. Therefore, the
674 inferior has essentially been killed & reborn. */
676 /* First collect the run target in effect. */
677 tgt = find_run_target ();
678 /* If we can't find one, things are in a very strange state... */
680 error ("Could find run target to save before following exec");
682 gdb_flush (gdb_stdout);
683 target_mourn_inferior ();
684 inferior_ptid = pid_to_ptid (saved_pid);
685 /* Because mourn_inferior resets inferior_ptid. */
688 /* That a.out is now the one to use. */
689 exec_file_attach (execd_pathname, 0);
691 /* And also is where symbols can be found. */
692 symbol_file_add_main (execd_pathname, 0);
694 /* Reset the shared library package. This ensures that we get
695 a shlib event when the child reaches "_start", at which point
696 the dld will have had a chance to initialize the child. */
697 #if defined(SOLIB_RESTART)
700 #ifdef SOLIB_CREATE_INFERIOR_HOOK
701 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
704 /* Reinsert all breakpoints. (Those which were symbolic have
705 been reset to the proper address in the new a.out, thanks
706 to symbol_file_command...) */
707 insert_breakpoints ();
709 /* The next resume of this inferior should bring it to the shlib
710 startup breakpoints. (If the user had also set bp's on
711 "main" from the old (parent) process, then they'll auto-
712 matically get reset there in the new process.) */
715 /* Non-zero if we just simulating a single-step. This is needed
716 because we cannot remove the breakpoints in the inferior process
717 until after the `wait' in `wait_for_inferior'. */
718 static int singlestep_breakpoints_inserted_p = 0;
721 /* Things to clean up if we QUIT out of resume (). */
724 resume_cleanups (void *ignore)
729 static const char schedlock_off[] = "off";
730 static const char schedlock_on[] = "on";
731 static const char schedlock_step[] = "step";
732 static const char *scheduler_mode = schedlock_off;
733 static const char *scheduler_enums[] = {
741 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
743 /* NOTE: cagney/2002-03-17: The add_show_from_set() function clones
744 the set command passed as a parameter. The clone operation will
745 include (BUG?) any ``set'' command callback, if present.
746 Commands like ``info set'' call all the ``show'' command
747 callbacks. Unfortunatly, for ``show'' commands cloned from
748 ``set'', this includes callbacks belonging to ``set'' commands.
749 Making this worse, this only occures if add_show_from_set() is
750 called after add_cmd_sfunc() (BUG?). */
751 if (cmd_type (c) == set_cmd)
752 if (!target_can_lock_scheduler)
754 scheduler_mode = schedlock_off;
755 error ("Target '%s' cannot support this command.", target_shortname);
760 /* Resume the inferior, but allow a QUIT. This is useful if the user
761 wants to interrupt some lengthy single-stepping operation
762 (for child processes, the SIGINT goes to the inferior, and so
763 we get a SIGINT random_signal, but for remote debugging and perhaps
764 other targets, that's not true).
766 STEP nonzero if we should step (zero to continue instead).
767 SIG is the signal to give the inferior (zero for none). */
769 resume (int step, enum target_signal sig)
771 int should_resume = 1;
772 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
775 /* FIXME: calling breakpoint_here_p (read_pc ()) three times! */
778 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
779 over an instruction that causes a page fault without triggering
780 a hardware watchpoint. The kernel properly notices that it shouldn't
781 stop, because the hardware watchpoint is not triggered, but it forgets
782 the step request and continues the program normally.
783 Work around the problem by removing hardware watchpoints if a step is
784 requested, GDB will check for a hardware watchpoint trigger after the
786 if (CANNOT_STEP_HW_WATCHPOINTS && step && breakpoints_inserted)
787 remove_hw_watchpoints ();
790 /* Normally, by the time we reach `resume', the breakpoints are either
791 removed or inserted, as appropriate. The exception is if we're sitting
792 at a permanent breakpoint; we need to step over it, but permanent
793 breakpoints can't be removed. So we have to test for it here. */
794 if (breakpoint_here_p (read_pc ()) == permanent_breakpoint_here)
795 SKIP_PERMANENT_BREAKPOINT ();
797 if (SOFTWARE_SINGLE_STEP_P () && step)
799 /* Do it the hard way, w/temp breakpoints */
800 SOFTWARE_SINGLE_STEP (sig, 1 /*insert-breakpoints */ );
801 /* ...and don't ask hardware to do it. */
803 /* and do not pull these breakpoints until after a `wait' in
804 `wait_for_inferior' */
805 singlestep_breakpoints_inserted_p = 1;
808 /* Handle any optimized stores to the inferior NOW... */
809 #ifdef DO_DEFERRED_STORES
813 /* If there were any forks/vforks/execs that were caught and are
814 now to be followed, then do so. */
815 switch (pending_follow.kind)
817 case (TARGET_WAITKIND_FORKED):
818 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
819 follow_fork (PIDGET (inferior_ptid),
820 pending_follow.fork_event.child_pid);
823 case (TARGET_WAITKIND_VFORKED):
825 int saw_child_exec = pending_follow.fork_event.saw_child_exec;
827 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
828 follow_vfork (PIDGET (inferior_ptid),
829 pending_follow.fork_event.child_pid);
831 /* Did we follow the child, but not yet see the child's exec event?
832 If so, then it actually ought to be waiting for us; we respond to
833 parent vfork events. We don't actually want to resume the child
834 in this situation; we want to just get its exec event. */
835 if (!saw_child_exec &&
836 (PIDGET (inferior_ptid) == pending_follow.fork_event.child_pid))
841 case (TARGET_WAITKIND_EXECD):
842 /* If we saw a vfork event but couldn't follow it until we saw
843 an exec, then now might be the time! */
844 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
845 /* follow_exec is called as soon as the exec event is seen. */
852 /* Install inferior's terminal modes. */
853 target_terminal_inferior ();
859 resume_ptid = RESUME_ALL; /* Default */
861 if ((step || singlestep_breakpoints_inserted_p) &&
862 !breakpoints_inserted && breakpoint_here_p (read_pc ()))
864 /* Stepping past a breakpoint without inserting breakpoints.
865 Make sure only the current thread gets to step, so that
866 other threads don't sneak past breakpoints while they are
869 resume_ptid = inferior_ptid;
872 if ((scheduler_mode == schedlock_on) ||
873 (scheduler_mode == schedlock_step &&
874 (step || singlestep_breakpoints_inserted_p)))
876 /* User-settable 'scheduler' mode requires solo thread resume. */
877 resume_ptid = inferior_ptid;
880 #ifdef CANNOT_STEP_BREAKPOINT
881 /* Most targets can step a breakpoint instruction, thus executing it
882 normally. But if this one cannot, just continue and we will hit
884 if (step && breakpoints_inserted && breakpoint_here_p (read_pc ()))
887 target_resume (resume_ptid, step, sig);
890 discard_cleanups (old_cleanups);
894 /* Clear out all variables saying what to do when inferior is continued.
895 First do this, then set the ones you want, then call `proceed'. */
898 clear_proceed_status (void)
901 step_range_start = 0;
903 step_frame_address = 0;
904 step_over_calls = STEP_OVER_UNDEBUGGABLE;
906 stop_soon_quietly = 0;
907 proceed_to_finish = 0;
908 breakpoint_proceeded = 1; /* We're about to proceed... */
910 /* Discard any remaining commands or status from previous stop. */
911 bpstat_clear (&stop_bpstat);
914 /* Basic routine for continuing the program in various fashions.
916 ADDR is the address to resume at, or -1 for resume where stopped.
917 SIGGNAL is the signal to give it, or 0 for none,
918 or -1 for act according to how it stopped.
919 STEP is nonzero if should trap after one instruction.
920 -1 means return after that and print nothing.
921 You should probably set various step_... variables
922 before calling here, if you are stepping.
924 You should call clear_proceed_status before calling proceed. */
927 proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
932 step_start_function = find_pc_function (read_pc ());
936 if (addr == (CORE_ADDR) -1)
938 /* If there is a breakpoint at the address we will resume at,
939 step one instruction before inserting breakpoints
940 so that we do not stop right away (and report a second
941 hit at this breakpoint). */
943 if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
946 #ifndef STEP_SKIPS_DELAY
947 #define STEP_SKIPS_DELAY(pc) (0)
948 #define STEP_SKIPS_DELAY_P (0)
950 /* Check breakpoint_here_p first, because breakpoint_here_p is fast
951 (it just checks internal GDB data structures) and STEP_SKIPS_DELAY
952 is slow (it needs to read memory from the target). */
953 if (STEP_SKIPS_DELAY_P
954 && breakpoint_here_p (read_pc () + 4)
955 && STEP_SKIPS_DELAY (read_pc ()))
963 #ifdef PREPARE_TO_PROCEED
964 /* In a multi-threaded task we may select another thread
965 and then continue or step.
967 But if the old thread was stopped at a breakpoint, it
968 will immediately cause another breakpoint stop without
969 any execution (i.e. it will report a breakpoint hit
970 incorrectly). So we must step over it first.
972 PREPARE_TO_PROCEED checks the current thread against the thread
973 that reported the most recent event. If a step-over is required
974 it returns TRUE and sets the current thread to the old thread. */
975 if (PREPARE_TO_PROCEED (1) && breakpoint_here_p (read_pc ()))
980 #endif /* PREPARE_TO_PROCEED */
983 if (trap_expected_after_continue)
985 /* If (step == 0), a trap will be automatically generated after
986 the first instruction is executed. Force step one
987 instruction to clear this condition. This should not occur
988 if step is nonzero, but it is harmless in that case. */
990 trap_expected_after_continue = 0;
992 #endif /* HP_OS_BUG */
995 /* We will get a trace trap after one instruction.
996 Continue it automatically and insert breakpoints then. */
1000 int temp = insert_breakpoints ();
1003 print_sys_errmsg ("insert_breakpoints", temp);
1004 error ("Cannot insert breakpoints.\n\
1005 The same program may be running in another process,\n\
1006 or you may have requested too many hardware\n\
1007 breakpoints and/or watchpoints.\n");
1010 breakpoints_inserted = 1;
1013 if (siggnal != TARGET_SIGNAL_DEFAULT)
1014 stop_signal = siggnal;
1015 /* If this signal should not be seen by program,
1016 give it zero. Used for debugging signals. */
1017 else if (!signal_program[stop_signal])
1018 stop_signal = TARGET_SIGNAL_0;
1020 annotate_starting ();
1022 /* Make sure that output from GDB appears before output from the
1024 gdb_flush (gdb_stdout);
1026 /* Resume inferior. */
1027 resume (oneproc || step || bpstat_should_step (), stop_signal);
1029 /* Wait for it to stop (if not standalone)
1030 and in any case decode why it stopped, and act accordingly. */
1031 /* Do this only if we are not using the event loop, or if the target
1032 does not support asynchronous execution. */
1033 if (!event_loop_p || !target_can_async_p ())
1035 wait_for_inferior ();
1040 /* Record the pc and sp of the program the last time it stopped.
1041 These are just used internally by wait_for_inferior, but need
1042 to be preserved over calls to it and cleared when the inferior
1044 static CORE_ADDR prev_pc;
1045 static CORE_ADDR prev_func_start;
1046 static char *prev_func_name;
1049 /* Start remote-debugging of a machine over a serial link. */
1054 init_thread_list ();
1055 init_wait_for_inferior ();
1056 stop_soon_quietly = 1;
1059 /* Always go on waiting for the target, regardless of the mode. */
1060 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1061 indicate to wait_for_inferior that a target should timeout if
1062 nothing is returned (instead of just blocking). Because of this,
1063 targets expecting an immediate response need to, internally, set
1064 things up so that the target_wait() is forced to eventually
1066 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1067 differentiate to its caller what the state of the target is after
1068 the initial open has been performed. Here we're assuming that
1069 the target has stopped. It should be possible to eventually have
1070 target_open() return to the caller an indication that the target
1071 is currently running and GDB state should be set to the same as
1072 for an async run. */
1073 wait_for_inferior ();
1077 /* Initialize static vars when a new inferior begins. */
1080 init_wait_for_inferior (void)
1082 /* These are meaningless until the first time through wait_for_inferior. */
1084 prev_func_start = 0;
1085 prev_func_name = NULL;
1088 trap_expected_after_continue = 0;
1090 breakpoints_inserted = 0;
1091 breakpoint_init_inferior (inf_starting);
1093 /* Don't confuse first call to proceed(). */
1094 stop_signal = TARGET_SIGNAL_0;
1096 /* The first resume is not following a fork/vfork/exec. */
1097 pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
1098 pending_follow.fork_event.saw_parent_fork = 0;
1099 pending_follow.fork_event.saw_child_fork = 0;
1100 pending_follow.fork_event.saw_child_exec = 0;
1102 /* See wait_for_inferior's handling of SYSCALL_ENTRY/RETURN events. */
1103 number_of_threads_in_syscalls = 0;
1105 clear_proceed_status ();
1109 delete_breakpoint_current_contents (void *arg)
1111 struct breakpoint **breakpointp = (struct breakpoint **) arg;
1112 if (*breakpointp != NULL)
1114 delete_breakpoint (*breakpointp);
1115 *breakpointp = NULL;
1119 /* This enum encodes possible reasons for doing a target_wait, so that
1120 wfi can call target_wait in one place. (Ultimately the call will be
1121 moved out of the infinite loop entirely.) */
1125 infwait_normal_state,
1126 infwait_thread_hop_state,
1127 infwait_nullified_state,
1128 infwait_nonstep_watch_state
1131 /* Why did the inferior stop? Used to print the appropriate messages
1132 to the interface from within handle_inferior_event(). */
1133 enum inferior_stop_reason
1135 /* We don't know why. */
1137 /* Step, next, nexti, stepi finished. */
1139 /* Found breakpoint. */
1141 /* Inferior terminated by signal. */
1143 /* Inferior exited. */
1145 /* Inferior received signal, and user asked to be notified. */
1149 /* This structure contains what used to be local variables in
1150 wait_for_inferior. Probably many of them can return to being
1151 locals in handle_inferior_event. */
1153 struct execution_control_state
1155 struct target_waitstatus ws;
1156 struct target_waitstatus *wp;
1159 CORE_ADDR stop_func_start;
1160 CORE_ADDR stop_func_end;
1161 char *stop_func_name;
1162 struct symtab_and_line sal;
1163 int remove_breakpoints_on_following_step;
1165 struct symtab *current_symtab;
1166 int handling_longjmp; /* FIXME */
1168 ptid_t saved_inferior_ptid;
1170 int stepping_through_solib_after_catch;
1171 bpstat stepping_through_solib_catchpoints;
1172 int enable_hw_watchpoints_after_wait;
1173 int stepping_through_sigtramp;
1174 int new_thread_event;
1175 struct target_waitstatus tmpstatus;
1176 enum infwait_states infwait_state;
1181 void init_execution_control_state (struct execution_control_state *ecs);
1183 void handle_inferior_event (struct execution_control_state *ecs);
1185 static void check_sigtramp2 (struct execution_control_state *ecs);
1186 static void step_into_function (struct execution_control_state *ecs);
1187 static void step_over_function (struct execution_control_state *ecs);
1188 static void stop_stepping (struct execution_control_state *ecs);
1189 static void prepare_to_wait (struct execution_control_state *ecs);
1190 static void keep_going (struct execution_control_state *ecs);
1191 static void print_stop_reason (enum inferior_stop_reason stop_reason,
1194 /* Wait for control to return from inferior to debugger.
1195 If inferior gets a signal, we may decide to start it up again
1196 instead of returning. That is why there is a loop in this function.
1197 When this function actually returns it means the inferior
1198 should be left stopped and GDB should read more commands. */
1201 wait_for_inferior (void)
1203 struct cleanup *old_cleanups;
1204 struct execution_control_state ecss;
1205 struct execution_control_state *ecs;
1207 old_cleanups = make_cleanup (delete_step_resume_breakpoint,
1208 &step_resume_breakpoint);
1209 make_cleanup (delete_breakpoint_current_contents,
1210 &through_sigtramp_breakpoint);
1212 /* wfi still stays in a loop, so it's OK just to take the address of
1213 a local to get the ecs pointer. */
1216 /* Fill in with reasonable starting values. */
1217 init_execution_control_state (ecs);
1219 /* We'll update this if & when we switch to a new thread. */
1220 previous_inferior_ptid = inferior_ptid;
1222 overlay_cache_invalid = 1;
1224 /* We have to invalidate the registers BEFORE calling target_wait
1225 because they can be loaded from the target while in target_wait.
1226 This makes remote debugging a bit more efficient for those
1227 targets that provide critical registers as part of their normal
1228 status mechanism. */
1230 registers_changed ();
1234 if (target_wait_hook)
1235 ecs->ptid = target_wait_hook (ecs->waiton_ptid, ecs->wp);
1237 ecs->ptid = target_wait (ecs->waiton_ptid, ecs->wp);
1239 /* Now figure out what to do with the result of the result. */
1240 handle_inferior_event (ecs);
1242 if (!ecs->wait_some_more)
1245 do_cleanups (old_cleanups);
1248 /* Asynchronous version of wait_for_inferior. It is called by the
1249 event loop whenever a change of state is detected on the file
1250 descriptor corresponding to the target. It can be called more than
1251 once to complete a single execution command. In such cases we need
1252 to keep the state in a global variable ASYNC_ECSS. If it is the
1253 last time that this function is called for a single execution
1254 command, then report to the user that the inferior has stopped, and
1255 do the necessary cleanups. */
1257 struct execution_control_state async_ecss;
1258 struct execution_control_state *async_ecs;
1261 fetch_inferior_event (void *client_data)
1263 static struct cleanup *old_cleanups;
1265 async_ecs = &async_ecss;
1267 if (!async_ecs->wait_some_more)
1269 old_cleanups = make_exec_cleanup (delete_step_resume_breakpoint,
1270 &step_resume_breakpoint);
1271 make_exec_cleanup (delete_breakpoint_current_contents,
1272 &through_sigtramp_breakpoint);
1274 /* Fill in with reasonable starting values. */
1275 init_execution_control_state (async_ecs);
1277 /* We'll update this if & when we switch to a new thread. */
1278 previous_inferior_ptid = inferior_ptid;
1280 overlay_cache_invalid = 1;
1282 /* We have to invalidate the registers BEFORE calling target_wait
1283 because they can be loaded from the target while in target_wait.
1284 This makes remote debugging a bit more efficient for those
1285 targets that provide critical registers as part of their normal
1286 status mechanism. */
1288 registers_changed ();
1291 if (target_wait_hook)
1293 target_wait_hook (async_ecs->waiton_ptid, async_ecs->wp);
1295 async_ecs->ptid = target_wait (async_ecs->waiton_ptid, async_ecs->wp);
1297 /* Now figure out what to do with the result of the result. */
1298 handle_inferior_event (async_ecs);
1300 if (!async_ecs->wait_some_more)
1302 /* Do only the cleanups that have been added by this
1303 function. Let the continuations for the commands do the rest,
1304 if there are any. */
1305 do_exec_cleanups (old_cleanups);
1307 if (step_multi && stop_step)
1308 inferior_event_handler (INF_EXEC_CONTINUE, NULL);
1310 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
1314 /* Prepare an execution control state for looping through a
1315 wait_for_inferior-type loop. */
1318 init_execution_control_state (struct execution_control_state *ecs)
1320 /* ecs->another_trap? */
1321 ecs->random_signal = 0;
1322 ecs->remove_breakpoints_on_following_step = 0;
1323 ecs->handling_longjmp = 0; /* FIXME */
1324 ecs->update_step_sp = 0;
1325 ecs->stepping_through_solib_after_catch = 0;
1326 ecs->stepping_through_solib_catchpoints = NULL;
1327 ecs->enable_hw_watchpoints_after_wait = 0;
1328 ecs->stepping_through_sigtramp = 0;
1329 ecs->sal = find_pc_line (prev_pc, 0);
1330 ecs->current_line = ecs->sal.line;
1331 ecs->current_symtab = ecs->sal.symtab;
1332 ecs->infwait_state = infwait_normal_state;
1333 ecs->waiton_ptid = pid_to_ptid (-1);
1334 ecs->wp = &(ecs->ws);
1337 /* Call this function before setting step_resume_breakpoint, as a
1338 sanity check. There should never be more than one step-resume
1339 breakpoint per thread, so we should never be setting a new
1340 step_resume_breakpoint when one is already active. */
1342 check_for_old_step_resume_breakpoint (void)
1344 if (step_resume_breakpoint)
1346 ("GDB bug: infrun.c (wait_for_inferior): dropping old step_resume breakpoint");
1349 /* Return the cached copy of the last pid/waitstatus returned by
1350 target_wait()/target_wait_hook(). The data is actually cached by
1351 handle_inferior_event(), which gets called immediately after
1352 target_wait()/target_wait_hook(). */
1355 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
1357 *ptidp = target_last_wait_ptid;
1358 *status = target_last_waitstatus;
1361 /* Switch thread contexts, maintaining "infrun state". */
1364 context_switch (struct execution_control_state *ecs)
1366 /* Caution: it may happen that the new thread (or the old one!)
1367 is not in the thread list. In this case we must not attempt
1368 to "switch context", or we run the risk that our context may
1369 be lost. This may happen as a result of the target module
1370 mishandling thread creation. */
1372 if (in_thread_list (inferior_ptid) && in_thread_list (ecs->ptid))
1373 { /* Perform infrun state context switch: */
1374 /* Save infrun state for the old thread. */
1375 save_infrun_state (inferior_ptid, prev_pc,
1376 prev_func_start, prev_func_name,
1377 trap_expected, step_resume_breakpoint,
1378 through_sigtramp_breakpoint, step_range_start,
1379 step_range_end, step_frame_address,
1380 ecs->handling_longjmp, ecs->another_trap,
1381 ecs->stepping_through_solib_after_catch,
1382 ecs->stepping_through_solib_catchpoints,
1383 ecs->stepping_through_sigtramp,
1384 ecs->current_line, ecs->current_symtab, step_sp);
1386 /* Load infrun state for the new thread. */
1387 load_infrun_state (ecs->ptid, &prev_pc,
1388 &prev_func_start, &prev_func_name,
1389 &trap_expected, &step_resume_breakpoint,
1390 &through_sigtramp_breakpoint, &step_range_start,
1391 &step_range_end, &step_frame_address,
1392 &ecs->handling_longjmp, &ecs->another_trap,
1393 &ecs->stepping_through_solib_after_catch,
1394 &ecs->stepping_through_solib_catchpoints,
1395 &ecs->stepping_through_sigtramp,
1396 &ecs->current_line, &ecs->current_symtab, &step_sp);
1398 inferior_ptid = ecs->ptid;
1402 /* Given an execution control state that has been freshly filled in
1403 by an event from the inferior, figure out what it means and take
1404 appropriate action. */
1407 handle_inferior_event (struct execution_control_state *ecs)
1410 int stepped_after_stopped_by_watchpoint;
1412 /* Cache the last pid/waitstatus. */
1413 target_last_wait_ptid = ecs->ptid;
1414 target_last_waitstatus = *ecs->wp;
1416 switch (ecs->infwait_state)
1418 case infwait_thread_hop_state:
1419 /* Cancel the waiton_ptid. */
1420 ecs->waiton_ptid = pid_to_ptid (-1);
1421 /* Fall thru to the normal_state case. */
1423 case infwait_normal_state:
1424 /* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
1425 is serviced in this loop, below. */
1426 if (ecs->enable_hw_watchpoints_after_wait)
1428 TARGET_ENABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
1429 ecs->enable_hw_watchpoints_after_wait = 0;
1431 stepped_after_stopped_by_watchpoint = 0;
1434 case infwait_nullified_state:
1437 case infwait_nonstep_watch_state:
1438 insert_breakpoints ();
1440 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1441 handle things like signals arriving and other things happening
1442 in combination correctly? */
1443 stepped_after_stopped_by_watchpoint = 1;
1446 ecs->infwait_state = infwait_normal_state;
1448 flush_cached_frames ();
1450 /* If it's a new process, add it to the thread database */
1452 ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
1453 && !in_thread_list (ecs->ptid));
1455 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
1456 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
1458 add_thread (ecs->ptid);
1460 ui_out_text (uiout, "[New ");
1461 ui_out_text (uiout, target_pid_or_tid_to_str (ecs->ptid));
1462 ui_out_text (uiout, "]\n");
1465 /* NOTE: This block is ONLY meant to be invoked in case of a
1466 "thread creation event"! If it is invoked for any other
1467 sort of event (such as a new thread landing on a breakpoint),
1468 the event will be discarded, which is almost certainly
1471 To avoid this, the low-level module (eg. target_wait)
1472 should call in_thread_list and add_thread, so that the
1473 new thread is known by the time we get here. */
1475 /* We may want to consider not doing a resume here in order
1476 to give the user a chance to play with the new thread.
1477 It might be good to make that a user-settable option. */
1479 /* At this point, all threads are stopped (happens
1480 automatically in either the OS or the native code).
1481 Therefore we need to continue all threads in order to
1484 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
1485 prepare_to_wait (ecs);
1490 switch (ecs->ws.kind)
1492 case TARGET_WAITKIND_LOADED:
1493 /* Ignore gracefully during startup of the inferior, as it
1494 might be the shell which has just loaded some objects,
1495 otherwise add the symbols for the newly loaded objects. */
1497 if (!stop_soon_quietly)
1499 /* Remove breakpoints, SOLIB_ADD might adjust
1500 breakpoint addresses via breakpoint_re_set. */
1501 if (breakpoints_inserted)
1502 remove_breakpoints ();
1504 /* Check for any newly added shared libraries if we're
1505 supposed to be adding them automatically. Switch
1506 terminal for any messages produced by
1507 breakpoint_re_set. */
1508 target_terminal_ours_for_output ();
1509 SOLIB_ADD (NULL, 0, NULL, auto_solib_add);
1510 target_terminal_inferior ();
1512 /* Reinsert breakpoints and continue. */
1513 if (breakpoints_inserted)
1514 insert_breakpoints ();
1517 resume (0, TARGET_SIGNAL_0);
1518 prepare_to_wait (ecs);
1521 case TARGET_WAITKIND_SPURIOUS:
1522 resume (0, TARGET_SIGNAL_0);
1523 prepare_to_wait (ecs);
1526 case TARGET_WAITKIND_EXITED:
1527 target_terminal_ours (); /* Must do this before mourn anyway */
1528 print_stop_reason (EXITED, ecs->ws.value.integer);
1530 /* Record the exit code in the convenience variable $_exitcode, so
1531 that the user can inspect this again later. */
1532 set_internalvar (lookup_internalvar ("_exitcode"),
1533 value_from_longest (builtin_type_int,
1534 (LONGEST) ecs->ws.value.integer));
1535 gdb_flush (gdb_stdout);
1536 target_mourn_inferior ();
1537 singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
1538 stop_print_frame = 0;
1539 stop_stepping (ecs);
1542 case TARGET_WAITKIND_SIGNALLED:
1543 stop_print_frame = 0;
1544 stop_signal = ecs->ws.value.sig;
1545 target_terminal_ours (); /* Must do this before mourn anyway */
1547 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
1548 reach here unless the inferior is dead. However, for years
1549 target_kill() was called here, which hints that fatal signals aren't
1550 really fatal on some systems. If that's true, then some changes
1552 target_mourn_inferior ();
1554 print_stop_reason (SIGNAL_EXITED, stop_signal);
1555 singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
1556 stop_stepping (ecs);
1559 /* The following are the only cases in which we keep going;
1560 the above cases end in a continue or goto. */
1561 case TARGET_WAITKIND_FORKED:
1562 stop_signal = TARGET_SIGNAL_TRAP;
1563 pending_follow.kind = ecs->ws.kind;
1565 /* Ignore fork events reported for the parent; we're only
1566 interested in reacting to forks of the child. Note that
1567 we expect the child's fork event to be available if we
1568 waited for it now. */
1569 if (ptid_equal (inferior_ptid, ecs->ptid))
1571 pending_follow.fork_event.saw_parent_fork = 1;
1572 pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
1573 pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
1574 prepare_to_wait (ecs);
1579 pending_follow.fork_event.saw_child_fork = 1;
1580 pending_follow.fork_event.child_pid = PIDGET (ecs->ptid);
1581 pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
1584 stop_pc = read_pc_pid (ecs->ptid);
1585 ecs->saved_inferior_ptid = inferior_ptid;
1586 inferior_ptid = ecs->ptid;
1587 /* The second argument of bpstat_stop_status is meant to help
1588 distinguish between a breakpoint trap and a singlestep trap.
1589 This is only important on targets where DECR_PC_AFTER_BREAK
1590 is non-zero. The prev_pc test is meant to distinguish between
1591 singlestepping a trap instruction, and singlestepping thru a
1592 jump to the instruction following a trap instruction. */
1594 stop_bpstat = bpstat_stop_status (&stop_pc,
1595 currently_stepping (ecs) &&
1597 stop_pc - DECR_PC_AFTER_BREAK);
1598 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1599 inferior_ptid = ecs->saved_inferior_ptid;
1600 goto process_event_stop_test;
1602 /* If this a platform which doesn't allow a debugger to touch a
1603 vfork'd inferior until after it exec's, then we'd best keep
1604 our fingers entirely off the inferior, other than continuing
1605 it. This has the unfortunate side-effect that catchpoints
1606 of vforks will be ignored. But since the platform doesn't
1607 allow the inferior be touched at vfork time, there's really
1609 case TARGET_WAITKIND_VFORKED:
1610 stop_signal = TARGET_SIGNAL_TRAP;
1611 pending_follow.kind = ecs->ws.kind;
1613 /* Is this a vfork of the parent? If so, then give any
1614 vfork catchpoints a chance to trigger now. (It's
1615 dangerous to do so if the child canot be touched until
1616 it execs, and the child has not yet exec'd. We probably
1617 should warn the user to that effect when the catchpoint
1619 if (ptid_equal (ecs->ptid, inferior_ptid))
1621 pending_follow.fork_event.saw_parent_fork = 1;
1622 pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
1623 pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
1626 /* If we've seen the child's vfork event but cannot really touch
1627 the child until it execs, then we must continue the child now.
1628 Else, give any vfork catchpoints a chance to trigger now. */
1631 pending_follow.fork_event.saw_child_fork = 1;
1632 pending_follow.fork_event.child_pid = PIDGET (ecs->ptid);
1633 pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
1634 target_post_startup_inferior (pid_to_ptid
1635 (pending_follow.fork_event.
1637 follow_vfork_when_exec = !target_can_follow_vfork_prior_to_exec ();
1638 if (follow_vfork_when_exec)
1640 target_resume (ecs->ptid, 0, TARGET_SIGNAL_0);
1641 prepare_to_wait (ecs);
1646 stop_pc = read_pc ();
1647 /* The second argument of bpstat_stop_status is meant to help
1648 distinguish between a breakpoint trap and a singlestep trap.
1649 This is only important on targets where DECR_PC_AFTER_BREAK
1650 is non-zero. The prev_pc test is meant to distinguish between
1651 singlestepping a trap instruction, and singlestepping thru a
1652 jump to the instruction following a trap instruction. */
1654 stop_bpstat = bpstat_stop_status (&stop_pc,
1655 currently_stepping (ecs) &&
1657 stop_pc - DECR_PC_AFTER_BREAK);
1658 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1659 goto process_event_stop_test;
1661 case TARGET_WAITKIND_EXECD:
1662 stop_signal = TARGET_SIGNAL_TRAP;
1664 /* Is this a target which reports multiple exec events per actual
1665 call to exec()? (HP-UX using ptrace does, for example.) If so,
1666 ignore all but the last one. Just resume the exec'r, and wait
1667 for the next exec event. */
1668 if (inferior_ignoring_leading_exec_events)
1670 inferior_ignoring_leading_exec_events--;
1671 if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
1672 ENSURE_VFORKING_PARENT_REMAINS_STOPPED (pending_follow.fork_event.
1674 target_resume (ecs->ptid, 0, TARGET_SIGNAL_0);
1675 prepare_to_wait (ecs);
1678 inferior_ignoring_leading_exec_events =
1679 target_reported_exec_events_per_exec_call () - 1;
1681 pending_follow.execd_pathname =
1682 savestring (ecs->ws.value.execd_pathname,
1683 strlen (ecs->ws.value.execd_pathname));
1685 /* Did inferior_ptid exec, or did a (possibly not-yet-followed)
1686 child of a vfork exec?
1688 ??rehrauer: This is unabashedly an HP-UX specific thing. On
1689 HP-UX, events associated with a vforking inferior come in
1690 threes: a vfork event for the child (always first), followed
1691 a vfork event for the parent and an exec event for the child.
1692 The latter two can come in either order.
1694 If we get the parent vfork event first, life's good: We follow
1695 either the parent or child, and then the child's exec event is
1698 But if we get the child's exec event first, then we delay
1699 responding to it until we handle the parent's vfork. Because,
1700 otherwise we can't satisfy a "catch vfork". */
1701 if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
1703 pending_follow.fork_event.saw_child_exec = 1;
1705 /* On some targets, the child must be resumed before
1706 the parent vfork event is delivered. A single-step
1708 if (RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK ())
1709 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1710 /* We expect the parent vfork event to be available now. */
1711 prepare_to_wait (ecs);
1715 /* This causes the eventpoints and symbol table to be reset. Must
1716 do this now, before trying to determine whether to stop. */
1717 follow_exec (PIDGET (inferior_ptid), pending_follow.execd_pathname);
1718 xfree (pending_follow.execd_pathname);
1720 stop_pc = read_pc_pid (ecs->ptid);
1721 ecs->saved_inferior_ptid = inferior_ptid;
1722 inferior_ptid = ecs->ptid;
1723 /* The second argument of bpstat_stop_status is meant to help
1724 distinguish between a breakpoint trap and a singlestep trap.
1725 This is only important on targets where DECR_PC_AFTER_BREAK
1726 is non-zero. The prev_pc test is meant to distinguish between
1727 singlestepping a trap instruction, and singlestepping thru a
1728 jump to the instruction following a trap instruction. */
1730 stop_bpstat = bpstat_stop_status (&stop_pc,
1731 currently_stepping (ecs) &&
1733 stop_pc - DECR_PC_AFTER_BREAK);
1734 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1735 inferior_ptid = ecs->saved_inferior_ptid;
1736 goto process_event_stop_test;
1738 /* These syscall events are returned on HP-UX, as part of its
1739 implementation of page-protection-based "hardware" watchpoints.
1740 HP-UX has unfortunate interactions between page-protections and
1741 some system calls. Our solution is to disable hardware watches
1742 when a system call is entered, and reenable them when the syscall
1743 completes. The downside of this is that we may miss the precise
1744 point at which a watched piece of memory is modified. "Oh well."
1746 Note that we may have multiple threads running, which may each
1747 enter syscalls at roughly the same time. Since we don't have a
1748 good notion currently of whether a watched piece of memory is
1749 thread-private, we'd best not have any page-protections active
1750 when any thread is in a syscall. Thus, we only want to reenable
1751 hardware watches when no threads are in a syscall.
1753 Also, be careful not to try to gather much state about a thread
1754 that's in a syscall. It's frequently a losing proposition. */
1755 case TARGET_WAITKIND_SYSCALL_ENTRY:
1756 number_of_threads_in_syscalls++;
1757 if (number_of_threads_in_syscalls == 1)
1759 TARGET_DISABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
1761 resume (0, TARGET_SIGNAL_0);
1762 prepare_to_wait (ecs);
1765 /* Before examining the threads further, step this thread to
1766 get it entirely out of the syscall. (We get notice of the
1767 event when the thread is just on the verge of exiting a
1768 syscall. Stepping one instruction seems to get it back
1771 Note that although the logical place to reenable h/w watches
1772 is here, we cannot. We cannot reenable them before stepping
1773 the thread (this causes the next wait on the thread to hang).
1775 Nor can we enable them after stepping until we've done a wait.
1776 Thus, we simply set the flag ecs->enable_hw_watchpoints_after_wait
1777 here, which will be serviced immediately after the target
1779 case TARGET_WAITKIND_SYSCALL_RETURN:
1780 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1782 if (number_of_threads_in_syscalls > 0)
1784 number_of_threads_in_syscalls--;
1785 ecs->enable_hw_watchpoints_after_wait =
1786 (number_of_threads_in_syscalls == 0);
1788 prepare_to_wait (ecs);
1791 case TARGET_WAITKIND_STOPPED:
1792 stop_signal = ecs->ws.value.sig;
1795 /* We had an event in the inferior, but we are not interested
1796 in handling it at this level. The lower layers have already
1797 done what needs to be done, if anything. This case can
1798 occur only when the target is async or extended-async. One
1799 of the circumstamces for this to happen is when the
1800 inferior produces output for the console. The inferior has
1801 not stopped, and we are ignoring the event. */
1802 case TARGET_WAITKIND_IGNORE:
1803 ecs->wait_some_more = 1;
1807 /* We may want to consider not doing a resume here in order to give
1808 the user a chance to play with the new thread. It might be good
1809 to make that a user-settable option. */
1811 /* At this point, all threads are stopped (happens automatically in
1812 either the OS or the native code). Therefore we need to continue
1813 all threads in order to make progress. */
1814 if (ecs->new_thread_event)
1816 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
1817 prepare_to_wait (ecs);
1821 stop_pc = read_pc_pid (ecs->ptid);
1823 /* See if a thread hit a thread-specific breakpoint that was meant for
1824 another thread. If so, then step that thread past the breakpoint,
1827 if (stop_signal == TARGET_SIGNAL_TRAP)
1829 if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
1830 ecs->random_signal = 0;
1831 else if (breakpoints_inserted
1832 && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK))
1834 ecs->random_signal = 0;
1835 if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK,
1840 /* Saw a breakpoint, but it was hit by the wrong thread.
1842 if (DECR_PC_AFTER_BREAK)
1843 write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, ecs->ptid);
1845 remove_status = remove_breakpoints ();
1846 /* Did we fail to remove breakpoints? If so, try
1847 to set the PC past the bp. (There's at least
1848 one situation in which we can fail to remove
1849 the bp's: On HP-UX's that use ttrace, we can't
1850 change the address space of a vforking child
1851 process until the child exits (well, okay, not
1852 then either :-) or execs. */
1853 if (remove_status != 0)
1855 /* FIXME! This is obviously non-portable! */
1856 write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK + 4, ecs->ptid);
1857 /* We need to restart all the threads now,
1858 * unles we're running in scheduler-locked mode.
1859 * Use currently_stepping to determine whether to
1862 /* FIXME MVS: is there any reason not to call resume()? */
1863 if (scheduler_mode == schedlock_on)
1864 target_resume (ecs->ptid,
1865 currently_stepping (ecs), TARGET_SIGNAL_0);
1867 target_resume (RESUME_ALL,
1868 currently_stepping (ecs), TARGET_SIGNAL_0);
1869 prepare_to_wait (ecs);
1874 breakpoints_inserted = 0;
1875 if (!ptid_equal (inferior_ptid, ecs->ptid))
1876 context_switch (ecs);
1877 ecs->waiton_ptid = ecs->ptid;
1878 ecs->wp = &(ecs->ws);
1879 ecs->another_trap = 1;
1881 ecs->infwait_state = infwait_thread_hop_state;
1883 registers_changed ();
1890 ecs->random_signal = 1;
1892 /* See if something interesting happened to the non-current thread. If
1893 so, then switch to that thread, and eventually give control back to
1896 Note that if there's any kind of pending follow (i.e., of a fork,
1897 vfork or exec), we don't want to do this now. Rather, we'll let
1898 the next resume handle it. */
1899 if (!ptid_equal (ecs->ptid, inferior_ptid) &&
1900 (pending_follow.kind == TARGET_WAITKIND_SPURIOUS))
1904 /* If it's a random signal for a non-current thread, notify user
1905 if he's expressed an interest. */
1906 if (ecs->random_signal && signal_print[stop_signal])
1908 /* ??rehrauer: I don't understand the rationale for this code. If the
1909 inferior will stop as a result of this signal, then the act of handling
1910 the stop ought to print a message that's couches the stoppage in user
1911 terms, e.g., "Stopped for breakpoint/watchpoint". If the inferior
1912 won't stop as a result of the signal -- i.e., if the signal is merely
1913 a side-effect of something GDB's doing "under the covers" for the
1914 user, such as stepping threads over a breakpoint they shouldn't stop
1915 for -- then the message seems to be a serious annoyance at best.
1917 For now, remove the message altogether. */
1920 target_terminal_ours_for_output ();
1921 printf_filtered ("\nProgram received signal %s, %s.\n",
1922 target_signal_to_name (stop_signal),
1923 target_signal_to_string (stop_signal));
1924 gdb_flush (gdb_stdout);
1928 /* If it's not SIGTRAP and not a signal we want to stop for, then
1929 continue the thread. */
1931 if (stop_signal != TARGET_SIGNAL_TRAP && !signal_stop[stop_signal])
1934 target_terminal_inferior ();
1936 /* Clear the signal if it should not be passed. */
1937 if (signal_program[stop_signal] == 0)
1938 stop_signal = TARGET_SIGNAL_0;
1940 target_resume (ecs->ptid, 0, stop_signal);
1941 prepare_to_wait (ecs);
1945 /* It's a SIGTRAP or a signal we're interested in. Switch threads,
1946 and fall into the rest of wait_for_inferior(). */
1948 context_switch (ecs);
1951 context_hook (pid_to_thread_id (ecs->ptid));
1953 flush_cached_frames ();
1956 if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
1958 /* Pull the single step breakpoints out of the target. */
1959 SOFTWARE_SINGLE_STEP (0, 0);
1960 singlestep_breakpoints_inserted_p = 0;
1963 /* If PC is pointing at a nullified instruction, then step beyond
1964 it so that the user won't be confused when GDB appears to be ready
1967 /* if (INSTRUCTION_NULLIFIED && currently_stepping (ecs)) */
1968 if (INSTRUCTION_NULLIFIED)
1970 registers_changed ();
1971 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1973 /* We may have received a signal that we want to pass to
1974 the inferior; therefore, we must not clobber the waitstatus
1977 ecs->infwait_state = infwait_nullified_state;
1978 ecs->waiton_ptid = ecs->ptid;
1979 ecs->wp = &(ecs->tmpstatus);
1980 prepare_to_wait (ecs);
1984 /* It may not be necessary to disable the watchpoint to stop over
1985 it. For example, the PA can (with some kernel cooperation)
1986 single step over a watchpoint without disabling the watchpoint. */
1987 if (HAVE_STEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
1990 prepare_to_wait (ecs);
1994 /* It is far more common to need to disable a watchpoint to step
1995 the inferior over it. FIXME. What else might a debug
1996 register or page protection watchpoint scheme need here? */
1997 if (HAVE_NONSTEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
1999 /* At this point, we are stopped at an instruction which has
2000 attempted to write to a piece of memory under control of
2001 a watchpoint. The instruction hasn't actually executed
2002 yet. If we were to evaluate the watchpoint expression
2003 now, we would get the old value, and therefore no change
2004 would seem to have occurred.
2006 In order to make watchpoints work `right', we really need
2007 to complete the memory write, and then evaluate the
2008 watchpoint expression. The following code does that by
2009 removing the watchpoint (actually, all watchpoints and
2010 breakpoints), single-stepping the target, re-inserting
2011 watchpoints, and then falling through to let normal
2012 single-step processing handle proceed. Since this
2013 includes evaluating watchpoints, things will come to a
2014 stop in the correct manner. */
2016 if (DECR_PC_AFTER_BREAK)
2017 write_pc (stop_pc - DECR_PC_AFTER_BREAK);
2019 remove_breakpoints ();
2020 registers_changed ();
2021 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */
2023 ecs->waiton_ptid = ecs->ptid;
2024 ecs->wp = &(ecs->ws);
2025 ecs->infwait_state = infwait_nonstep_watch_state;
2026 prepare_to_wait (ecs);
2030 /* It may be possible to simply continue after a watchpoint. */
2031 if (HAVE_CONTINUABLE_WATCHPOINT)
2032 STOPPED_BY_WATCHPOINT (ecs->ws);
2034 ecs->stop_func_start = 0;
2035 ecs->stop_func_end = 0;
2036 ecs->stop_func_name = 0;
2037 /* Don't care about return value; stop_func_start and stop_func_name
2038 will both be 0 if it doesn't work. */
2039 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
2040 &ecs->stop_func_start, &ecs->stop_func_end);
2041 ecs->stop_func_start += FUNCTION_START_OFFSET;
2042 ecs->another_trap = 0;
2043 bpstat_clear (&stop_bpstat);
2045 stop_stack_dummy = 0;
2046 stop_print_frame = 1;
2047 ecs->random_signal = 0;
2048 stopped_by_random_signal = 0;
2049 breakpoints_failed = 0;
2051 /* Look at the cause of the stop, and decide what to do.
2052 The alternatives are:
2053 1) break; to really stop and return to the debugger,
2054 2) drop through to start up again
2055 (set ecs->another_trap to 1 to single step once)
2056 3) set ecs->random_signal to 1, and the decision between 1 and 2
2057 will be made according to the signal handling tables. */
2059 /* First, distinguish signals caused by the debugger from signals
2060 that have to do with the program's own actions.
2061 Note that breakpoint insns may cause SIGTRAP or SIGILL
2062 or SIGEMT, depending on the operating system version.
2063 Here we detect when a SIGILL or SIGEMT is really a breakpoint
2064 and change it to SIGTRAP. */
2066 if (stop_signal == TARGET_SIGNAL_TRAP
2067 || (breakpoints_inserted &&
2068 (stop_signal == TARGET_SIGNAL_ILL
2069 || stop_signal == TARGET_SIGNAL_EMT)) || stop_soon_quietly)
2071 if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
2073 stop_print_frame = 0;
2074 stop_stepping (ecs);
2077 if (stop_soon_quietly)
2079 stop_stepping (ecs);
2083 /* Don't even think about breakpoints
2084 if just proceeded over a breakpoint.
2086 However, if we are trying to proceed over a breakpoint
2087 and end up in sigtramp, then through_sigtramp_breakpoint
2088 will be set and we should check whether we've hit the
2090 if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected
2091 && through_sigtramp_breakpoint == NULL)
2092 bpstat_clear (&stop_bpstat);
2095 /* See if there is a breakpoint at the current PC. */
2097 /* The second argument of bpstat_stop_status is meant to help
2098 distinguish between a breakpoint trap and a singlestep trap.
2099 This is only important on targets where DECR_PC_AFTER_BREAK
2100 is non-zero. The prev_pc test is meant to distinguish between
2101 singlestepping a trap instruction, and singlestepping thru a
2102 jump to the instruction following a trap instruction. */
2104 stop_bpstat = bpstat_stop_status (&stop_pc,
2105 /* Pass TRUE if our reason for stopping is something other
2106 than hitting a breakpoint. We do this by checking that
2107 1) stepping is going on and 2) we didn't hit a breakpoint
2108 in a signal handler without an intervening stop in
2109 sigtramp, which is detected by a new stack pointer value
2110 below any usual function calling stack adjustments. */
2111 (currently_stepping (ecs)
2113 stop_pc - DECR_PC_AFTER_BREAK
2115 && INNER_THAN (read_sp (),
2118 /* Following in case break condition called a
2120 stop_print_frame = 1;
2123 if (stop_signal == TARGET_SIGNAL_TRAP)
2125 = !(bpstat_explains_signal (stop_bpstat)
2127 || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
2128 && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
2129 FRAME_FP (get_current_frame ())))
2130 || (step_range_end && step_resume_breakpoint == NULL));
2134 ecs->random_signal = !(bpstat_explains_signal (stop_bpstat)
2135 /* End of a stack dummy. Some systems (e.g. Sony
2136 news) give another signal besides SIGTRAP, so
2137 check here as well as above. */
2138 || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
2139 && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
2143 if (!ecs->random_signal)
2144 stop_signal = TARGET_SIGNAL_TRAP;
2148 /* When we reach this point, we've pretty much decided
2149 that the reason for stopping must've been a random
2150 (unexpected) signal. */
2153 ecs->random_signal = 1;
2154 /* If a fork, vfork or exec event was seen, then there are two
2155 possible responses we can make:
2157 1. If a catchpoint triggers for the event (ecs->random_signal == 0),
2158 then we must stop now and issue a prompt. We will resume
2159 the inferior when the user tells us to.
2160 2. If no catchpoint triggers for the event (ecs->random_signal == 1),
2161 then we must resume the inferior now and keep checking.
2163 In either case, we must take appropriate steps to "follow" the
2164 the fork/vfork/exec when the inferior is resumed. For example,
2165 if follow-fork-mode is "child", then we must detach from the
2166 parent inferior and follow the new child inferior.
2168 In either case, setting pending_follow causes the next resume()
2169 to take the appropriate following action. */
2170 process_event_stop_test:
2171 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
2173 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2176 stop_signal = TARGET_SIGNAL_0;
2181 else if (ecs->ws.kind == TARGET_WAITKIND_VFORKED)
2183 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2185 stop_signal = TARGET_SIGNAL_0;
2190 else if (ecs->ws.kind == TARGET_WAITKIND_EXECD)
2192 pending_follow.kind = ecs->ws.kind;
2193 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2196 stop_signal = TARGET_SIGNAL_0;
2202 /* For the program's own signals, act according to
2203 the signal handling tables. */
2205 if (ecs->random_signal)
2207 /* Signal not for debugging purposes. */
2210 stopped_by_random_signal = 1;
2212 if (signal_print[stop_signal])
2215 target_terminal_ours_for_output ();
2216 print_stop_reason (SIGNAL_RECEIVED, stop_signal);
2218 if (signal_stop[stop_signal])
2220 stop_stepping (ecs);
2223 /* If not going to stop, give terminal back
2224 if we took it away. */
2226 target_terminal_inferior ();
2228 /* Clear the signal if it should not be passed. */
2229 if (signal_program[stop_signal] == 0)
2230 stop_signal = TARGET_SIGNAL_0;
2232 /* I'm not sure whether this needs to be check_sigtramp2 or
2233 whether it could/should be keep_going.
2235 This used to jump to step_over_function if we are stepping,
2238 Suppose the user does a `next' over a function call, and while
2239 that call is in progress, the inferior receives a signal for
2240 which GDB does not stop (i.e., signal_stop[SIG] is false). In
2241 that case, when we reach this point, there is already a
2242 step-resume breakpoint established, right where it should be:
2243 immediately after the function call the user is "next"-ing
2244 over. If we call step_over_function now, two bad things
2247 - we'll create a new breakpoint, at wherever the current
2248 frame's return address happens to be. That could be
2249 anywhere, depending on what function call happens to be on
2250 the top of the stack at that point. Point is, it's probably
2251 not where we need it.
2253 - the existing step-resume breakpoint (which is at the correct
2254 address) will get orphaned: step_resume_breakpoint will point
2255 to the new breakpoint, and the old step-resume breakpoint
2256 will never be cleaned up.
2258 The old behavior was meant to help HP-UX single-step out of
2259 sigtramps. It would place the new breakpoint at prev_pc, which
2260 was certainly wrong. I don't know the details there, so fixing
2261 this probably breaks that. As with anything else, it's up to
2262 the HP-UX maintainer to furnish a fix that doesn't break other
2263 platforms. --JimB, 20 May 1999 */
2264 check_sigtramp2 (ecs);
2269 /* Handle cases caused by hitting a breakpoint. */
2271 CORE_ADDR jmp_buf_pc;
2272 struct bpstat_what what;
2274 what = bpstat_what (stop_bpstat);
2276 if (what.call_dummy)
2278 stop_stack_dummy = 1;
2280 trap_expected_after_continue = 1;
2284 switch (what.main_action)
2286 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
2287 /* If we hit the breakpoint at longjmp, disable it for the
2288 duration of this command. Then, install a temporary
2289 breakpoint at the target of the jmp_buf. */
2290 disable_longjmp_breakpoint ();
2291 remove_breakpoints ();
2292 breakpoints_inserted = 0;
2293 if (!GET_LONGJMP_TARGET_P () || !GET_LONGJMP_TARGET (&jmp_buf_pc))
2299 /* Need to blow away step-resume breakpoint, as it
2300 interferes with us */
2301 if (step_resume_breakpoint != NULL)
2303 delete_step_resume_breakpoint (&step_resume_breakpoint);
2305 /* Not sure whether we need to blow this away too, but probably
2306 it is like the step-resume breakpoint. */
2307 if (through_sigtramp_breakpoint != NULL)
2309 delete_breakpoint (through_sigtramp_breakpoint);
2310 through_sigtramp_breakpoint = NULL;
2314 /* FIXME - Need to implement nested temporary breakpoints */
2315 if (step_over_calls > 0)
2316 set_longjmp_resume_breakpoint (jmp_buf_pc, get_current_frame ());
2319 set_longjmp_resume_breakpoint (jmp_buf_pc, NULL);
2320 ecs->handling_longjmp = 1; /* FIXME */
2324 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
2325 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
2326 remove_breakpoints ();
2327 breakpoints_inserted = 0;
2329 /* FIXME - Need to implement nested temporary breakpoints */
2331 && (INNER_THAN (FRAME_FP (get_current_frame ()),
2332 step_frame_address)))
2334 ecs->another_trap = 1;
2339 disable_longjmp_breakpoint ();
2340 ecs->handling_longjmp = 0; /* FIXME */
2341 if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
2343 /* else fallthrough */
2345 case BPSTAT_WHAT_SINGLE:
2346 if (breakpoints_inserted)
2348 remove_breakpoints ();
2350 breakpoints_inserted = 0;
2351 ecs->another_trap = 1;
2352 /* Still need to check other stuff, at least the case
2353 where we are stepping and step out of the right range. */
2356 case BPSTAT_WHAT_STOP_NOISY:
2357 stop_print_frame = 1;
2359 /* We are about to nuke the step_resume_breakpoint and
2360 through_sigtramp_breakpoint via the cleanup chain, so
2361 no need to worry about it here. */
2363 stop_stepping (ecs);
2366 case BPSTAT_WHAT_STOP_SILENT:
2367 stop_print_frame = 0;
2369 /* We are about to nuke the step_resume_breakpoint and
2370 through_sigtramp_breakpoint via the cleanup chain, so
2371 no need to worry about it here. */
2373 stop_stepping (ecs);
2376 case BPSTAT_WHAT_STEP_RESUME:
2377 /* This proably demands a more elegant solution, but, yeah
2380 This function's use of the simple variable
2381 step_resume_breakpoint doesn't seem to accomodate
2382 simultaneously active step-resume bp's, although the
2383 breakpoint list certainly can.
2385 If we reach here and step_resume_breakpoint is already
2386 NULL, then apparently we have multiple active
2387 step-resume bp's. We'll just delete the breakpoint we
2388 stopped at, and carry on.
2390 Correction: what the code currently does is delete a
2391 step-resume bp, but it makes no effort to ensure that
2392 the one deleted is the one currently stopped at. MVS */
2394 if (step_resume_breakpoint == NULL)
2396 step_resume_breakpoint =
2397 bpstat_find_step_resume_breakpoint (stop_bpstat);
2399 delete_step_resume_breakpoint (&step_resume_breakpoint);
2402 case BPSTAT_WHAT_THROUGH_SIGTRAMP:
2403 if (through_sigtramp_breakpoint)
2404 delete_breakpoint (through_sigtramp_breakpoint);
2405 through_sigtramp_breakpoint = NULL;
2407 /* If were waiting for a trap, hitting the step_resume_break
2408 doesn't count as getting it. */
2410 ecs->another_trap = 1;
2413 case BPSTAT_WHAT_CHECK_SHLIBS:
2414 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
2417 /* Remove breakpoints, we eventually want to step over the
2418 shlib event breakpoint, and SOLIB_ADD might adjust
2419 breakpoint addresses via breakpoint_re_set. */
2420 if (breakpoints_inserted)
2421 remove_breakpoints ();
2422 breakpoints_inserted = 0;
2424 /* Check for any newly added shared libraries if we're
2425 supposed to be adding them automatically. Switch
2426 terminal for any messages produced by
2427 breakpoint_re_set. */
2428 target_terminal_ours_for_output ();
2429 SOLIB_ADD (NULL, 0, NULL, auto_solib_add);
2430 target_terminal_inferior ();
2432 /* Try to reenable shared library breakpoints, additional
2433 code segments in shared libraries might be mapped in now. */
2434 re_enable_breakpoints_in_shlibs ();
2436 /* If requested, stop when the dynamic linker notifies
2437 gdb of events. This allows the user to get control
2438 and place breakpoints in initializer routines for
2439 dynamically loaded objects (among other things). */
2440 if (stop_on_solib_events)
2442 stop_stepping (ecs);
2446 /* If we stopped due to an explicit catchpoint, then the
2447 (see above) call to SOLIB_ADD pulled in any symbols
2448 from a newly-loaded library, if appropriate.
2450 We do want the inferior to stop, but not where it is
2451 now, which is in the dynamic linker callback. Rather,
2452 we would like it stop in the user's program, just after
2453 the call that caused this catchpoint to trigger. That
2454 gives the user a more useful vantage from which to
2455 examine their program's state. */
2456 else if (what.main_action ==
2457 BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
2459 /* ??rehrauer: If I could figure out how to get the
2460 right return PC from here, we could just set a temp
2461 breakpoint and resume. I'm not sure we can without
2462 cracking open the dld's shared libraries and sniffing
2463 their unwind tables and text/data ranges, and that's
2464 not a terribly portable notion.
2466 Until that time, we must step the inferior out of the
2467 dld callback, and also out of the dld itself (and any
2468 code or stubs in libdld.sl, such as "shl_load" and
2469 friends) until we reach non-dld code. At that point,
2470 we can stop stepping. */
2471 bpstat_get_triggered_catchpoints (stop_bpstat,
2473 stepping_through_solib_catchpoints);
2474 ecs->stepping_through_solib_after_catch = 1;
2476 /* Be sure to lift all breakpoints, so the inferior does
2477 actually step past this point... */
2478 ecs->another_trap = 1;
2483 /* We want to step over this breakpoint, then keep going. */
2484 ecs->another_trap = 1;
2491 case BPSTAT_WHAT_LAST:
2492 /* Not a real code, but listed here to shut up gcc -Wall. */
2494 case BPSTAT_WHAT_KEEP_CHECKING:
2499 /* We come here if we hit a breakpoint but should not
2500 stop for it. Possibly we also were stepping
2501 and should stop for that. So fall through and
2502 test for stepping. But, if not stepping,
2505 /* Are we stepping to get the inferior out of the dynamic
2506 linker's hook (and possibly the dld itself) after catching
2508 if (ecs->stepping_through_solib_after_catch)
2510 #if defined(SOLIB_ADD)
2511 /* Have we reached our destination? If not, keep going. */
2512 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc))
2514 ecs->another_trap = 1;
2519 /* Else, stop and report the catchpoint(s) whose triggering
2520 caused us to begin stepping. */
2521 ecs->stepping_through_solib_after_catch = 0;
2522 bpstat_clear (&stop_bpstat);
2523 stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints);
2524 bpstat_clear (&ecs->stepping_through_solib_catchpoints);
2525 stop_print_frame = 1;
2526 stop_stepping (ecs);
2530 if (!CALL_DUMMY_BREAKPOINT_OFFSET_P)
2532 /* This is the old way of detecting the end of the stack dummy.
2533 An architecture which defines CALL_DUMMY_BREAKPOINT_OFFSET gets
2534 handled above. As soon as we can test it on all of them, all
2535 architectures should define it. */
2537 /* If this is the breakpoint at the end of a stack dummy,
2538 just stop silently, unless the user was doing an si/ni, in which
2539 case she'd better know what she's doing. */
2541 if (CALL_DUMMY_HAS_COMPLETED (stop_pc, read_sp (),
2542 FRAME_FP (get_current_frame ()))
2545 stop_print_frame = 0;
2546 stop_stack_dummy = 1;
2548 trap_expected_after_continue = 1;
2550 stop_stepping (ecs);
2555 if (step_resume_breakpoint)
2557 /* Having a step-resume breakpoint overrides anything
2558 else having to do with stepping commands until
2559 that breakpoint is reached. */
2560 /* I'm not sure whether this needs to be check_sigtramp2 or
2561 whether it could/should be keep_going. */
2562 check_sigtramp2 (ecs);
2567 if (step_range_end == 0)
2569 /* Likewise if we aren't even stepping. */
2570 /* I'm not sure whether this needs to be check_sigtramp2 or
2571 whether it could/should be keep_going. */
2572 check_sigtramp2 (ecs);
2577 /* If stepping through a line, keep going if still within it.
2579 Note that step_range_end is the address of the first instruction
2580 beyond the step range, and NOT the address of the last instruction
2582 if (stop_pc >= step_range_start && stop_pc < step_range_end)
2584 /* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal.
2585 So definately need to check for sigtramp here. */
2586 check_sigtramp2 (ecs);
2591 /* We stepped out of the stepping range. */
2593 /* If we are stepping at the source level and entered the runtime
2594 loader dynamic symbol resolution code, we keep on single stepping
2595 until we exit the run time loader code and reach the callee's
2597 if (step_over_calls == STEP_OVER_UNDEBUGGABLE
2598 && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc))
2600 CORE_ADDR pc_after_resolver = SKIP_SOLIB_RESOLVER (stop_pc);
2602 if (pc_after_resolver)
2604 /* Set up a step-resume breakpoint at the address
2605 indicated by SKIP_SOLIB_RESOLVER. */
2606 struct symtab_and_line sr_sal;
2608 sr_sal.pc = pc_after_resolver;
2610 check_for_old_step_resume_breakpoint ();
2611 step_resume_breakpoint =
2612 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2613 if (breakpoints_inserted)
2614 insert_breakpoints ();
2621 /* We can't update step_sp every time through the loop, because
2622 reading the stack pointer would slow down stepping too much.
2623 But we can update it every time we leave the step range. */
2624 ecs->update_step_sp = 1;
2626 /* Did we just take a signal? */
2627 if (PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2628 && !PC_IN_SIGTRAMP (prev_pc, prev_func_name)
2629 && INNER_THAN (read_sp (), step_sp))
2631 /* We've just taken a signal; go until we are back to
2632 the point where we took it and one more. */
2634 /* Note: The test above succeeds not only when we stepped
2635 into a signal handler, but also when we step past the last
2636 statement of a signal handler and end up in the return stub
2637 of the signal handler trampoline. To distinguish between
2638 these two cases, check that the frame is INNER_THAN the
2639 previous one below. pai/1997-09-11 */
2643 CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
2645 if (INNER_THAN (current_frame, step_frame_address))
2647 /* We have just taken a signal; go until we are back to
2648 the point where we took it and one more. */
2650 /* This code is needed at least in the following case:
2651 The user types "next" and then a signal arrives (before
2652 the "next" is done). */
2654 /* Note that if we are stopped at a breakpoint, then we need
2655 the step_resume breakpoint to override any breakpoints at
2656 the same location, so that we will still step over the
2657 breakpoint even though the signal happened. */
2658 struct symtab_and_line sr_sal;
2661 sr_sal.symtab = NULL;
2663 sr_sal.pc = prev_pc;
2664 /* We could probably be setting the frame to
2665 step_frame_address; I don't think anyone thought to
2667 check_for_old_step_resume_breakpoint ();
2668 step_resume_breakpoint =
2669 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2670 if (breakpoints_inserted)
2671 insert_breakpoints ();
2675 /* We just stepped out of a signal handler and into
2676 its calling trampoline.
2678 Normally, we'd call step_over_function from
2679 here, but for some reason GDB can't unwind the
2680 stack correctly to find the real PC for the point
2681 user code where the signal trampoline will return
2682 -- FRAME_SAVED_PC fails, at least on HP-UX 10.20.
2683 But signal trampolines are pretty small stubs of
2684 code, anyway, so it's OK instead to just
2685 single-step out. Note: assuming such trampolines
2686 don't exhibit recursion on any platform... */
2687 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
2688 &ecs->stop_func_start,
2689 &ecs->stop_func_end);
2690 /* Readjust stepping range */
2691 step_range_start = ecs->stop_func_start;
2692 step_range_end = ecs->stop_func_end;
2693 ecs->stepping_through_sigtramp = 1;
2698 /* If this is stepi or nexti, make sure that the stepping range
2699 gets us past that instruction. */
2700 if (step_range_end == 1)
2701 /* FIXME: Does this run afoul of the code below which, if
2702 we step into the middle of a line, resets the stepping
2704 step_range_end = (step_range_start = prev_pc) + 1;
2706 ecs->remove_breakpoints_on_following_step = 1;
2711 if (stop_pc == ecs->stop_func_start /* Quick test */
2712 || (in_prologue (stop_pc, ecs->stop_func_start) &&
2713 !IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2714 || IN_SOLIB_CALL_TRAMPOLINE (stop_pc, ecs->stop_func_name)
2715 || ecs->stop_func_name == 0)
2717 /* It's a subroutine call. */
2719 if ((step_over_calls == STEP_OVER_NONE)
2720 || ((step_range_end == 1)
2721 && in_prologue (prev_pc, ecs->stop_func_start)))
2723 /* I presume that step_over_calls is only 0 when we're
2724 supposed to be stepping at the assembly language level
2725 ("stepi"). Just stop. */
2726 /* Also, maybe we just did a "nexti" inside a prolog,
2727 so we thought it was a subroutine call but it was not.
2728 Stop as well. FENN */
2730 print_stop_reason (END_STEPPING_RANGE, 0);
2731 stop_stepping (ecs);
2735 if (step_over_calls == STEP_OVER_ALL || IGNORE_HELPER_CALL (stop_pc))
2737 /* We're doing a "next". */
2739 if (PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2740 && INNER_THAN (step_frame_address, read_sp ()))
2741 /* We stepped out of a signal handler, and into its
2742 calling trampoline. This is misdetected as a
2743 subroutine call, but stepping over the signal
2744 trampoline isn't such a bad idea. In order to do
2745 that, we have to ignore the value in
2746 step_frame_address, since that doesn't represent the
2747 frame that'll reach when we return from the signal
2748 trampoline. Otherwise we'll probably continue to the
2749 end of the program. */
2750 step_frame_address = 0;
2752 step_over_function (ecs);
2757 /* If we are in a function call trampoline (a stub between
2758 the calling routine and the real function), locate the real
2759 function. That's what tells us (a) whether we want to step
2760 into it at all, and (b) what prologue we want to run to
2761 the end of, if we do step into it. */
2762 tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
2764 ecs->stop_func_start = tmp;
2767 tmp = DYNAMIC_TRAMPOLINE_NEXTPC (stop_pc);
2770 struct symtab_and_line xxx;
2771 /* Why isn't this s_a_l called "sr_sal", like all of the
2772 other s_a_l's where this code is duplicated? */
2773 INIT_SAL (&xxx); /* initialize to zeroes */
2775 xxx.section = find_pc_overlay (xxx.pc);
2776 check_for_old_step_resume_breakpoint ();
2777 step_resume_breakpoint =
2778 set_momentary_breakpoint (xxx, NULL, bp_step_resume);
2779 insert_breakpoints ();
2785 /* If we have line number information for the function we
2786 are thinking of stepping into, step into it.
2788 If there are several symtabs at that PC (e.g. with include
2789 files), just want to know whether *any* of them have line
2790 numbers. find_pc_line handles this. */
2792 struct symtab_and_line tmp_sal;
2794 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
2795 if (tmp_sal.line != 0)
2797 step_into_function (ecs);
2802 /* If we have no line number and the step-stop-if-no-debug
2803 is set, we stop the step so that the user has a chance to
2804 switch in assembly mode. */
2805 if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug)
2808 print_stop_reason (END_STEPPING_RANGE, 0);
2809 stop_stepping (ecs);
2813 step_over_function (ecs);
2819 /* We've wandered out of the step range. */
2821 ecs->sal = find_pc_line (stop_pc, 0);
2823 if (step_range_end == 1)
2825 /* It is stepi or nexti. We always want to stop stepping after
2828 print_stop_reason (END_STEPPING_RANGE, 0);
2829 stop_stepping (ecs);
2833 /* If we're in the return path from a shared library trampoline,
2834 we want to proceed through the trampoline when stepping. */
2835 if (IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2839 /* Determine where this trampoline returns. */
2840 tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
2842 /* Only proceed through if we know where it's going. */
2845 /* And put the step-breakpoint there and go until there. */
2846 struct symtab_and_line sr_sal;
2848 INIT_SAL (&sr_sal); /* initialize to zeroes */
2850 sr_sal.section = find_pc_overlay (sr_sal.pc);
2851 /* Do not specify what the fp should be when we stop
2852 since on some machines the prologue
2853 is where the new fp value is established. */
2854 check_for_old_step_resume_breakpoint ();
2855 step_resume_breakpoint =
2856 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2857 if (breakpoints_inserted)
2858 insert_breakpoints ();
2860 /* Restart without fiddling with the step ranges or
2867 if (ecs->sal.line == 0)
2869 /* We have no line number information. That means to stop
2870 stepping (does this always happen right after one instruction,
2871 when we do "s" in a function with no line numbers,
2872 or can this happen as a result of a return or longjmp?). */
2874 print_stop_reason (END_STEPPING_RANGE, 0);
2875 stop_stepping (ecs);
2879 if ((stop_pc == ecs->sal.pc)
2880 && (ecs->current_line != ecs->sal.line
2881 || ecs->current_symtab != ecs->sal.symtab))
2883 /* We are at the start of a different line. So stop. Note that
2884 we don't stop if we step into the middle of a different line.
2885 That is said to make things like for (;;) statements work
2888 print_stop_reason (END_STEPPING_RANGE, 0);
2889 stop_stepping (ecs);
2893 /* We aren't done stepping.
2895 Optimize by setting the stepping range to the line.
2896 (We might not be in the original line, but if we entered a
2897 new line in mid-statement, we continue stepping. This makes
2898 things like for(;;) statements work better.) */
2900 if (ecs->stop_func_end && ecs->sal.end >= ecs->stop_func_end)
2902 /* If this is the last line of the function, don't keep stepping
2903 (it would probably step us out of the function).
2904 This is particularly necessary for a one-line function,
2905 in which after skipping the prologue we better stop even though
2906 we will be in mid-line. */
2908 print_stop_reason (END_STEPPING_RANGE, 0);
2909 stop_stepping (ecs);
2912 step_range_start = ecs->sal.pc;
2913 step_range_end = ecs->sal.end;
2914 step_frame_address = FRAME_FP (get_current_frame ());
2915 ecs->current_line = ecs->sal.line;
2916 ecs->current_symtab = ecs->sal.symtab;
2918 /* In the case where we just stepped out of a function into the middle
2919 of a line of the caller, continue stepping, but step_frame_address
2920 must be modified to current frame */
2922 CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
2923 if (!(INNER_THAN (current_frame, step_frame_address)))
2924 step_frame_address = current_frame;
2930 /* Are we in the middle of stepping? */
2933 currently_stepping (struct execution_control_state *ecs)
2935 return ((through_sigtramp_breakpoint == NULL
2936 && !ecs->handling_longjmp
2937 && ((step_range_end && step_resume_breakpoint == NULL)
2939 || ecs->stepping_through_solib_after_catch
2940 || bpstat_should_step ());
2944 check_sigtramp2 (struct execution_control_state *ecs)
2947 && PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2948 && !PC_IN_SIGTRAMP (prev_pc, prev_func_name)
2949 && INNER_THAN (read_sp (), step_sp))
2951 /* What has happened here is that we have just stepped the
2952 inferior with a signal (because it is a signal which
2953 shouldn't make us stop), thus stepping into sigtramp.
2955 So we need to set a step_resume_break_address breakpoint and
2956 continue until we hit it, and then step. FIXME: This should
2957 be more enduring than a step_resume breakpoint; we should
2958 know that we will later need to keep going rather than
2959 re-hitting the breakpoint here (see the testsuite,
2960 gdb.base/signals.exp where it says "exceedingly difficult"). */
2962 struct symtab_and_line sr_sal;
2964 INIT_SAL (&sr_sal); /* initialize to zeroes */
2965 sr_sal.pc = prev_pc;
2966 sr_sal.section = find_pc_overlay (sr_sal.pc);
2967 /* We perhaps could set the frame if we kept track of what the
2968 frame corresponding to prev_pc was. But we don't, so don't. */
2969 through_sigtramp_breakpoint =
2970 set_momentary_breakpoint (sr_sal, NULL, bp_through_sigtramp);
2971 if (breakpoints_inserted)
2972 insert_breakpoints ();
2974 ecs->remove_breakpoints_on_following_step = 1;
2975 ecs->another_trap = 1;
2979 /* Subroutine call with source code we should not step over. Do step
2980 to the first line of code in it. */
2983 step_into_function (struct execution_control_state *ecs)
2986 struct symtab_and_line sr_sal;
2988 s = find_pc_symtab (stop_pc);
2989 if (s && s->language != language_asm)
2990 ecs->stop_func_start = SKIP_PROLOGUE (ecs->stop_func_start);
2992 ecs->sal = find_pc_line (ecs->stop_func_start, 0);
2993 /* Use the step_resume_break to step until the end of the prologue,
2994 even if that involves jumps (as it seems to on the vax under
2996 /* If the prologue ends in the middle of a source line, continue to
2997 the end of that source line (if it is still within the function).
2998 Otherwise, just go to end of prologue. */
2999 #ifdef PROLOGUE_FIRSTLINE_OVERLAP
3000 /* no, don't either. It skips any code that's legitimately on the
3004 && ecs->sal.pc != ecs->stop_func_start
3005 && ecs->sal.end < ecs->stop_func_end)
3006 ecs->stop_func_start = ecs->sal.end;
3009 if (ecs->stop_func_start == stop_pc)
3011 /* We are already there: stop now. */
3013 print_stop_reason (END_STEPPING_RANGE, 0);
3014 stop_stepping (ecs);
3019 /* Put the step-breakpoint there and go until there. */
3020 INIT_SAL (&sr_sal); /* initialize to zeroes */
3021 sr_sal.pc = ecs->stop_func_start;
3022 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
3023 /* Do not specify what the fp should be when we stop since on
3024 some machines the prologue is where the new fp value is
3026 check_for_old_step_resume_breakpoint ();
3027 step_resume_breakpoint =
3028 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
3029 if (breakpoints_inserted)
3030 insert_breakpoints ();
3032 /* And make sure stepping stops right away then. */
3033 step_range_end = step_range_start;
3038 /* We've just entered a callee, and we wish to resume until it returns
3039 to the caller. Setting a step_resume breakpoint on the return
3040 address will catch a return from the callee.
3042 However, if the callee is recursing, we want to be careful not to
3043 catch returns of those recursive calls, but only of THIS instance
3046 To do this, we set the step_resume bp's frame to our current
3047 caller's frame (step_frame_address, which is set by the "next" or
3048 "until" command, before execution begins). */
3051 step_over_function (struct execution_control_state *ecs)
3053 struct symtab_and_line sr_sal;
3055 INIT_SAL (&sr_sal); /* initialize to zeros */
3056 sr_sal.pc = ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ()));
3057 sr_sal.section = find_pc_overlay (sr_sal.pc);
3059 check_for_old_step_resume_breakpoint ();
3060 step_resume_breakpoint =
3061 set_momentary_breakpoint (sr_sal, get_current_frame (), bp_step_resume);
3063 if (step_frame_address && !IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
3064 step_resume_breakpoint->frame = step_frame_address;
3066 if (breakpoints_inserted)
3067 insert_breakpoints ();
3071 stop_stepping (struct execution_control_state *ecs)
3073 if (target_has_execution)
3075 /* Are we stopping for a vfork event? We only stop when we see
3076 the child's event. However, we may not yet have seen the
3077 parent's event. And, inferior_ptid is still set to the
3078 parent's pid, until we resume again and follow either the
3081 To ensure that we can really touch inferior_ptid (aka, the
3082 parent process) -- which calls to functions like read_pc
3083 implicitly do -- wait on the parent if necessary. */
3084 if ((pending_follow.kind == TARGET_WAITKIND_VFORKED)
3085 && !pending_follow.fork_event.saw_parent_fork)
3091 if (target_wait_hook)
3092 parent_ptid = target_wait_hook (pid_to_ptid (-1), &(ecs->ws));
3094 parent_ptid = target_wait (pid_to_ptid (-1), &(ecs->ws));
3096 while (!ptid_equal (parent_ptid, inferior_ptid));
3099 /* Assuming the inferior still exists, set these up for next
3100 time, just like we did above if we didn't break out of the
3102 prev_pc = read_pc ();
3103 prev_func_start = ecs->stop_func_start;
3104 prev_func_name = ecs->stop_func_name;
3107 /* Let callers know we don't want to wait for the inferior anymore. */
3108 ecs->wait_some_more = 0;
3111 /* This function handles various cases where we need to continue
3112 waiting for the inferior. */
3113 /* (Used to be the keep_going: label in the old wait_for_inferior) */
3116 keep_going (struct execution_control_state *ecs)
3118 /* ??rehrauer: ttrace on HP-UX theoretically allows one to debug a
3119 vforked child between its creation and subsequent exit or call to
3120 exec(). However, I had big problems in this rather creaky exec
3121 engine, getting that to work. The fundamental problem is that
3122 I'm trying to debug two processes via an engine that only
3123 understands a single process with possibly multiple threads.
3125 Hence, this spot is known to have problems when
3126 target_can_follow_vfork_prior_to_exec returns 1. */
3128 /* Save the pc before execution, to compare with pc after stop. */
3129 prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
3130 prev_func_start = ecs->stop_func_start; /* Ok, since if DECR_PC_AFTER
3131 BREAK is defined, the
3132 original pc would not have
3133 been at the start of a
3135 prev_func_name = ecs->stop_func_name;
3137 if (ecs->update_step_sp)
3138 step_sp = read_sp ();
3139 ecs->update_step_sp = 0;
3141 /* If we did not do break;, it means we should keep running the
3142 inferior and not return to debugger. */
3144 if (trap_expected && stop_signal != TARGET_SIGNAL_TRAP)
3146 /* We took a signal (which we are supposed to pass through to
3147 the inferior, else we'd have done a break above) and we
3148 haven't yet gotten our trap. Simply continue. */
3149 resume (currently_stepping (ecs), stop_signal);
3153 /* Either the trap was not expected, but we are continuing
3154 anyway (the user asked that this signal be passed to the
3157 The signal was SIGTRAP, e.g. it was our signal, but we
3158 decided we should resume from it.
3160 We're going to run this baby now!
3162 Insert breakpoints now, unless we are trying to one-proceed
3163 past a breakpoint. */
3164 /* If we've just finished a special step resume and we don't
3165 want to hit a breakpoint, pull em out. */
3166 if (step_resume_breakpoint == NULL
3167 && through_sigtramp_breakpoint == NULL
3168 && ecs->remove_breakpoints_on_following_step)
3170 ecs->remove_breakpoints_on_following_step = 0;
3171 remove_breakpoints ();
3172 breakpoints_inserted = 0;
3174 else if (!breakpoints_inserted &&
3175 (through_sigtramp_breakpoint != NULL || !ecs->another_trap))
3177 breakpoints_failed = insert_breakpoints ();
3178 if (breakpoints_failed)
3180 stop_stepping (ecs);
3183 breakpoints_inserted = 1;
3186 trap_expected = ecs->another_trap;
3188 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3189 specifies that such a signal should be delivered to the
3192 Typically, this would occure when a user is debugging a
3193 target monitor on a simulator: the target monitor sets a
3194 breakpoint; the simulator encounters this break-point and
3195 halts the simulation handing control to GDB; GDB, noteing
3196 that the break-point isn't valid, returns control back to the
3197 simulator; the simulator then delivers the hardware
3198 equivalent of a SIGNAL_TRAP to the program being debugged. */
3200 if (stop_signal == TARGET_SIGNAL_TRAP && !signal_program[stop_signal])
3201 stop_signal = TARGET_SIGNAL_0;
3203 #ifdef SHIFT_INST_REGS
3204 /* I'm not sure when this following segment applies. I do know,
3205 now, that we shouldn't rewrite the regs when we were stopped
3206 by a random signal from the inferior process. */
3207 /* FIXME: Shouldn't this be based on the valid bit of the SXIP?
3208 (this is only used on the 88k). */
3210 if (!bpstat_explains_signal (stop_bpstat)
3211 && (stop_signal != TARGET_SIGNAL_CHLD) && !stopped_by_random_signal)
3213 #endif /* SHIFT_INST_REGS */
3215 resume (currently_stepping (ecs), stop_signal);
3218 prepare_to_wait (ecs);
3221 /* This function normally comes after a resume, before
3222 handle_inferior_event exits. It takes care of any last bits of
3223 housekeeping, and sets the all-important wait_some_more flag. */
3226 prepare_to_wait (struct execution_control_state *ecs)
3228 if (ecs->infwait_state == infwait_normal_state)
3230 overlay_cache_invalid = 1;
3232 /* We have to invalidate the registers BEFORE calling
3233 target_wait because they can be loaded from the target while
3234 in target_wait. This makes remote debugging a bit more
3235 efficient for those targets that provide critical registers
3236 as part of their normal status mechanism. */
3238 registers_changed ();
3239 ecs->waiton_ptid = pid_to_ptid (-1);
3240 ecs->wp = &(ecs->ws);
3242 /* This is the old end of the while loop. Let everybody know we
3243 want to wait for the inferior some more and get called again
3245 ecs->wait_some_more = 1;
3248 /* Print why the inferior has stopped. We always print something when
3249 the inferior exits, or receives a signal. The rest of the cases are
3250 dealt with later on in normal_stop() and print_it_typical(). Ideally
3251 there should be a call to this function from handle_inferior_event()
3252 each time stop_stepping() is called.*/
3254 print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
3256 switch (stop_reason)
3259 /* We don't deal with these cases from handle_inferior_event()
3262 case END_STEPPING_RANGE:
3263 /* We are done with a step/next/si/ni command. */
3264 /* For now print nothing. */
3265 /* Print a message only if not in the middle of doing a "step n"
3266 operation for n > 1 */
3267 if (!step_multi || !stop_step)
3268 if (ui_out_is_mi_like_p (uiout))
3269 ui_out_field_string (uiout, "reason", "end-stepping-range");
3271 case BREAKPOINT_HIT:
3272 /* We found a breakpoint. */
3273 /* For now print nothing. */
3276 /* The inferior was terminated by a signal. */
3277 annotate_signalled ();
3278 if (ui_out_is_mi_like_p (uiout))
3279 ui_out_field_string (uiout, "reason", "exited-signalled");
3280 ui_out_text (uiout, "\nProgram terminated with signal ");
3281 annotate_signal_name ();
3282 ui_out_field_string (uiout, "signal-name",
3283 target_signal_to_name (stop_info));
3284 annotate_signal_name_end ();
3285 ui_out_text (uiout, ", ");
3286 annotate_signal_string ();
3287 ui_out_field_string (uiout, "signal-meaning",
3288 target_signal_to_string (stop_info));
3289 annotate_signal_string_end ();
3290 ui_out_text (uiout, ".\n");
3291 ui_out_text (uiout, "The program no longer exists.\n");
3294 /* The inferior program is finished. */
3295 annotate_exited (stop_info);
3298 if (ui_out_is_mi_like_p (uiout))
3299 ui_out_field_string (uiout, "reason", "exited");
3300 ui_out_text (uiout, "\nProgram exited with code ");
3301 ui_out_field_fmt (uiout, "exit-code", "0%o",
3302 (unsigned int) stop_info);
3303 ui_out_text (uiout, ".\n");
3307 if (ui_out_is_mi_like_p (uiout))
3308 ui_out_field_string (uiout, "reason", "exited-normally");
3309 ui_out_text (uiout, "\nProgram exited normally.\n");
3312 case SIGNAL_RECEIVED:
3313 /* Signal received. The signal table tells us to print about
3316 ui_out_text (uiout, "\nProgram received signal ");
3317 annotate_signal_name ();
3318 if (ui_out_is_mi_like_p (uiout))
3319 ui_out_field_string (uiout, "reason", "signal-received");
3320 ui_out_field_string (uiout, "signal-name",
3321 target_signal_to_name (stop_info));
3322 annotate_signal_name_end ();
3323 ui_out_text (uiout, ", ");
3324 annotate_signal_string ();
3325 ui_out_field_string (uiout, "signal-meaning",
3326 target_signal_to_string (stop_info));
3327 annotate_signal_string_end ();
3328 ui_out_text (uiout, ".\n");
3331 internal_error (__FILE__, __LINE__,
3332 "print_stop_reason: unrecognized enum value");
3338 /* Here to return control to GDB when the inferior stops for real.
3339 Print appropriate messages, remove breakpoints, give terminal our modes.
3341 STOP_PRINT_FRAME nonzero means print the executing frame
3342 (pc, function, args, file, line number and line text).
3343 BREAKPOINTS_FAILED nonzero means stop was due to error
3344 attempting to insert breakpoints. */
3349 /* As with the notification of thread events, we want to delay
3350 notifying the user that we've switched thread context until
3351 the inferior actually stops.
3353 (Note that there's no point in saying anything if the inferior
3355 if (!ptid_equal (previous_inferior_ptid, inferior_ptid)
3356 && target_has_execution)
3358 target_terminal_ours_for_output ();
3359 printf_filtered ("[Switching to %s]\n",
3360 target_pid_or_tid_to_str (inferior_ptid));
3361 previous_inferior_ptid = inferior_ptid;
3364 /* Make sure that the current_frame's pc is correct. This
3365 is a correction for setting up the frame info before doing
3366 DECR_PC_AFTER_BREAK */
3367 if (target_has_execution && get_current_frame ())
3368 (get_current_frame ())->pc = read_pc ();
3370 if (breakpoints_failed)
3372 target_terminal_ours_for_output ();
3373 print_sys_errmsg ("While inserting breakpoints", breakpoints_failed);
3374 printf_filtered ("Stopped; cannot insert breakpoints.\n\
3375 The same program may be running in another process,\n\
3376 or you may have requested too many hardware breakpoints\n\
3377 and/or watchpoints.\n");
3380 if (target_has_execution && breakpoints_inserted)
3382 if (remove_breakpoints ())
3384 target_terminal_ours_for_output ();
3385 printf_filtered ("Cannot remove breakpoints because ");
3386 printf_filtered ("program is no longer writable.\n");
3387 printf_filtered ("It might be running in another process.\n");
3388 printf_filtered ("Further execution is probably impossible.\n");
3391 breakpoints_inserted = 0;
3393 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3394 Delete any breakpoint that is to be deleted at the next stop. */
3396 breakpoint_auto_delete (stop_bpstat);
3398 /* If an auto-display called a function and that got a signal,
3399 delete that auto-display to avoid an infinite recursion. */
3401 if (stopped_by_random_signal)
3402 disable_current_display ();
3404 /* Don't print a message if in the middle of doing a "step n"
3405 operation for n > 1 */
3406 if (step_multi && stop_step)
3409 target_terminal_ours ();
3411 /* Look up the hook_stop and run it (CLI internally handles problem
3412 of stop_command's pre-hook not existing). */
3414 catch_errors (hook_stop_stub, stop_command,
3415 "Error while running hook_stop:\n", RETURN_MASK_ALL);
3417 if (!target_has_stack)
3423 /* Select innermost stack frame - i.e., current frame is frame 0,
3424 and current location is based on that.
3425 Don't do this on return from a stack dummy routine,
3426 or if the program has exited. */
3428 if (!stop_stack_dummy)
3430 select_frame (get_current_frame ());
3432 /* Print current location without a level number, if
3433 we have changed functions or hit a breakpoint.
3434 Print source line if we have one.
3435 bpstat_print() contains the logic deciding in detail
3436 what to print, based on the event(s) that just occurred. */
3438 if (stop_print_frame && selected_frame)
3442 int do_frame_printing = 1;
3444 bpstat_ret = bpstat_print (stop_bpstat);
3449 && step_frame_address == FRAME_FP (get_current_frame ())
3450 && step_start_function == find_pc_function (stop_pc))
3451 source_flag = SRC_LINE; /* finished step, just print source line */
3453 source_flag = SRC_AND_LOC; /* print location and source line */
3455 case PRINT_SRC_AND_LOC:
3456 source_flag = SRC_AND_LOC; /* print location and source line */
3458 case PRINT_SRC_ONLY:
3459 source_flag = SRC_LINE;
3462 source_flag = SRC_LINE; /* something bogus */
3463 do_frame_printing = 0;
3466 internal_error (__FILE__, __LINE__, "Unknown value.");
3468 /* For mi, have the same behavior every time we stop:
3469 print everything but the source line. */
3470 if (ui_out_is_mi_like_p (uiout))
3471 source_flag = LOC_AND_ADDRESS;
3473 if (ui_out_is_mi_like_p (uiout))
3474 ui_out_field_int (uiout, "thread-id",
3475 pid_to_thread_id (inferior_ptid));
3476 /* The behavior of this routine with respect to the source
3478 SRC_LINE: Print only source line
3479 LOCATION: Print only location
3480 SRC_AND_LOC: Print location and source line */
3481 if (do_frame_printing)
3482 show_and_print_stack_frame (selected_frame, -1, source_flag);
3484 /* Display the auto-display expressions. */
3489 /* Save the function value return registers, if we care.
3490 We might be about to restore their previous contents. */
3491 if (proceed_to_finish)
3492 /* NB: The copy goes through to the target picking up the value of
3493 all the registers. */
3494 regcache_cpy (stop_registers, current_regcache);
3496 if (stop_stack_dummy)
3498 /* Pop the empty frame that contains the stack dummy.
3499 POP_FRAME ends with a setting of the current frame, so we
3500 can use that next. */
3502 /* Set stop_pc to what it was before we called the function.
3503 Can't rely on restore_inferior_status because that only gets
3504 called if we don't stop in the called function. */
3505 stop_pc = read_pc ();
3506 select_frame (get_current_frame ());
3510 annotate_stopped ();
3514 hook_stop_stub (void *cmd)
3516 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
3521 signal_stop_state (int signo)
3523 return signal_stop[signo];
3527 signal_print_state (int signo)
3529 return signal_print[signo];
3533 signal_pass_state (int signo)
3535 return signal_program[signo];
3539 signal_stop_update (signo, state)
3543 int ret = signal_stop[signo];
3544 signal_stop[signo] = state;
3549 signal_print_update (signo, state)
3553 int ret = signal_print[signo];
3554 signal_print[signo] = state;
3559 signal_pass_update (signo, state)
3563 int ret = signal_program[signo];
3564 signal_program[signo] = state;
3569 sig_print_header (void)
3572 Signal Stop\tPrint\tPass to program\tDescription\n");
3576 sig_print_info (enum target_signal oursig)
3578 char *name = target_signal_to_name (oursig);
3579 int name_padding = 13 - strlen (name);
3581 if (name_padding <= 0)
3584 printf_filtered ("%s", name);
3585 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
3586 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
3587 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
3588 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
3589 printf_filtered ("%s\n", target_signal_to_string (oursig));
3592 /* Specify how various signals in the inferior should be handled. */
3595 handle_command (char *args, int from_tty)
3598 int digits, wordlen;
3599 int sigfirst, signum, siglast;
3600 enum target_signal oursig;
3603 unsigned char *sigs;
3604 struct cleanup *old_chain;
3608 error_no_arg ("signal to handle");
3611 /* Allocate and zero an array of flags for which signals to handle. */
3613 nsigs = (int) TARGET_SIGNAL_LAST;
3614 sigs = (unsigned char *) alloca (nsigs);
3615 memset (sigs, 0, nsigs);
3617 /* Break the command line up into args. */
3619 argv = buildargv (args);
3624 old_chain = make_cleanup_freeargv (argv);
3626 /* Walk through the args, looking for signal oursigs, signal names, and
3627 actions. Signal numbers and signal names may be interspersed with
3628 actions, with the actions being performed for all signals cumulatively
3629 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
3631 while (*argv != NULL)
3633 wordlen = strlen (*argv);
3634 for (digits = 0; isdigit ((*argv)[digits]); digits++)
3638 sigfirst = siglast = -1;
3640 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
3642 /* Apply action to all signals except those used by the
3643 debugger. Silently skip those. */
3646 siglast = nsigs - 1;
3648 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
3650 SET_SIGS (nsigs, sigs, signal_stop);
3651 SET_SIGS (nsigs, sigs, signal_print);
3653 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
3655 UNSET_SIGS (nsigs, sigs, signal_program);
3657 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
3659 SET_SIGS (nsigs, sigs, signal_print);
3661 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
3663 SET_SIGS (nsigs, sigs, signal_program);
3665 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
3667 UNSET_SIGS (nsigs, sigs, signal_stop);
3669 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
3671 SET_SIGS (nsigs, sigs, signal_program);
3673 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
3675 UNSET_SIGS (nsigs, sigs, signal_print);
3676 UNSET_SIGS (nsigs, sigs, signal_stop);
3678 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
3680 UNSET_SIGS (nsigs, sigs, signal_program);
3682 else if (digits > 0)
3684 /* It is numeric. The numeric signal refers to our own
3685 internal signal numbering from target.h, not to host/target
3686 signal number. This is a feature; users really should be
3687 using symbolic names anyway, and the common ones like
3688 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
3690 sigfirst = siglast = (int)
3691 target_signal_from_command (atoi (*argv));
3692 if ((*argv)[digits] == '-')
3695 target_signal_from_command (atoi ((*argv) + digits + 1));
3697 if (sigfirst > siglast)
3699 /* Bet he didn't figure we'd think of this case... */
3707 oursig = target_signal_from_name (*argv);
3708 if (oursig != TARGET_SIGNAL_UNKNOWN)
3710 sigfirst = siglast = (int) oursig;
3714 /* Not a number and not a recognized flag word => complain. */
3715 error ("Unrecognized or ambiguous flag word: \"%s\".", *argv);
3719 /* If any signal numbers or symbol names were found, set flags for
3720 which signals to apply actions to. */
3722 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
3724 switch ((enum target_signal) signum)
3726 case TARGET_SIGNAL_TRAP:
3727 case TARGET_SIGNAL_INT:
3728 if (!allsigs && !sigs[signum])
3730 if (query ("%s is used by the debugger.\n\
3731 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal) signum)))
3737 printf_unfiltered ("Not confirmed, unchanged.\n");
3738 gdb_flush (gdb_stdout);
3742 case TARGET_SIGNAL_0:
3743 case TARGET_SIGNAL_DEFAULT:
3744 case TARGET_SIGNAL_UNKNOWN:
3745 /* Make sure that "all" doesn't print these. */
3756 target_notice_signals (inferior_ptid);
3760 /* Show the results. */
3761 sig_print_header ();
3762 for (signum = 0; signum < nsigs; signum++)
3766 sig_print_info (signum);
3771 do_cleanups (old_chain);
3775 xdb_handle_command (char *args, int from_tty)
3778 struct cleanup *old_chain;
3780 /* Break the command line up into args. */
3782 argv = buildargv (args);
3787 old_chain = make_cleanup_freeargv (argv);
3788 if (argv[1] != (char *) NULL)
3793 bufLen = strlen (argv[0]) + 20;
3794 argBuf = (char *) xmalloc (bufLen);
3798 enum target_signal oursig;
3800 oursig = target_signal_from_name (argv[0]);
3801 memset (argBuf, 0, bufLen);
3802 if (strcmp (argv[1], "Q") == 0)
3803 sprintf (argBuf, "%s %s", argv[0], "noprint");
3806 if (strcmp (argv[1], "s") == 0)
3808 if (!signal_stop[oursig])
3809 sprintf (argBuf, "%s %s", argv[0], "stop");
3811 sprintf (argBuf, "%s %s", argv[0], "nostop");
3813 else if (strcmp (argv[1], "i") == 0)
3815 if (!signal_program[oursig])
3816 sprintf (argBuf, "%s %s", argv[0], "pass");
3818 sprintf (argBuf, "%s %s", argv[0], "nopass");
3820 else if (strcmp (argv[1], "r") == 0)
3822 if (!signal_print[oursig])
3823 sprintf (argBuf, "%s %s", argv[0], "print");
3825 sprintf (argBuf, "%s %s", argv[0], "noprint");
3831 handle_command (argBuf, from_tty);
3833 printf_filtered ("Invalid signal handling flag.\n");
3838 do_cleanups (old_chain);
3841 /* Print current contents of the tables set by the handle command.
3842 It is possible we should just be printing signals actually used
3843 by the current target (but for things to work right when switching
3844 targets, all signals should be in the signal tables). */
3847 signals_info (char *signum_exp, int from_tty)
3849 enum target_signal oursig;
3850 sig_print_header ();
3854 /* First see if this is a symbol name. */
3855 oursig = target_signal_from_name (signum_exp);
3856 if (oursig == TARGET_SIGNAL_UNKNOWN)
3858 /* No, try numeric. */
3860 target_signal_from_command (parse_and_eval_long (signum_exp));
3862 sig_print_info (oursig);
3866 printf_filtered ("\n");
3867 /* These ugly casts brought to you by the native VAX compiler. */
3868 for (oursig = TARGET_SIGNAL_FIRST;
3869 (int) oursig < (int) TARGET_SIGNAL_LAST;
3870 oursig = (enum target_signal) ((int) oursig + 1))
3874 if (oursig != TARGET_SIGNAL_UNKNOWN
3875 && oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0)
3876 sig_print_info (oursig);
3879 printf_filtered ("\nUse the \"handle\" command to change these tables.\n");
3882 struct inferior_status
3884 enum target_signal stop_signal;
3888 int stop_stack_dummy;
3889 int stopped_by_random_signal;
3891 CORE_ADDR step_range_start;
3892 CORE_ADDR step_range_end;
3893 CORE_ADDR step_frame_address;
3894 enum step_over_calls_kind step_over_calls;
3895 CORE_ADDR step_resume_break_address;
3896 int stop_after_trap;
3897 int stop_soon_quietly;
3898 struct regcache *stop_registers;
3900 /* These are here because if call_function_by_hand has written some
3901 registers and then decides to call error(), we better not have changed
3903 struct regcache *registers;
3905 /* A frame unique identifier. */
3906 struct frame_id selected_frame_id;
3908 int breakpoint_proceeded;
3909 int restore_stack_info;
3910 int proceed_to_finish;
3914 write_inferior_status_register (struct inferior_status *inf_status, int regno,
3917 int size = REGISTER_RAW_SIZE (regno);
3918 void *buf = alloca (size);
3919 store_signed_integer (buf, size, val);
3920 regcache_write (inf_status->registers, regno, buf);
3923 /* Save all of the information associated with the inferior<==>gdb
3924 connection. INF_STATUS is a pointer to a "struct inferior_status"
3925 (defined in inferior.h). */
3927 struct inferior_status *
3928 save_inferior_status (int restore_stack_info)
3930 struct inferior_status *inf_status = XMALLOC (struct inferior_status);
3932 inf_status->stop_signal = stop_signal;
3933 inf_status->stop_pc = stop_pc;
3934 inf_status->stop_step = stop_step;
3935 inf_status->stop_stack_dummy = stop_stack_dummy;
3936 inf_status->stopped_by_random_signal = stopped_by_random_signal;
3937 inf_status->trap_expected = trap_expected;
3938 inf_status->step_range_start = step_range_start;
3939 inf_status->step_range_end = step_range_end;
3940 inf_status->step_frame_address = step_frame_address;
3941 inf_status->step_over_calls = step_over_calls;
3942 inf_status->stop_after_trap = stop_after_trap;
3943 inf_status->stop_soon_quietly = stop_soon_quietly;
3944 /* Save original bpstat chain here; replace it with copy of chain.
3945 If caller's caller is walking the chain, they'll be happier if we
3946 hand them back the original chain when restore_inferior_status is
3948 inf_status->stop_bpstat = stop_bpstat;
3949 stop_bpstat = bpstat_copy (stop_bpstat);
3950 inf_status->breakpoint_proceeded = breakpoint_proceeded;
3951 inf_status->restore_stack_info = restore_stack_info;
3952 inf_status->proceed_to_finish = proceed_to_finish;
3954 inf_status->stop_registers = regcache_dup_no_passthrough (stop_registers);
3956 inf_status->registers = regcache_dup (current_regcache);
3958 get_frame_id (selected_frame, &inf_status->selected_frame_id);
3963 restore_selected_frame (void *args)
3965 struct frame_id *fid = (struct frame_id *) args;
3966 struct frame_info *frame;
3968 frame = frame_find_by_id (*fid);
3970 /* If inf_status->selected_frame_address is NULL, there was no
3971 previously selected frame. */
3974 warning ("Unable to restore previously selected frame.\n");
3978 select_frame (frame);
3984 restore_inferior_status (struct inferior_status *inf_status)
3986 stop_signal = inf_status->stop_signal;
3987 stop_pc = inf_status->stop_pc;
3988 stop_step = inf_status->stop_step;
3989 stop_stack_dummy = inf_status->stop_stack_dummy;
3990 stopped_by_random_signal = inf_status->stopped_by_random_signal;
3991 trap_expected = inf_status->trap_expected;
3992 step_range_start = inf_status->step_range_start;
3993 step_range_end = inf_status->step_range_end;
3994 step_frame_address = inf_status->step_frame_address;
3995 step_over_calls = inf_status->step_over_calls;
3996 stop_after_trap = inf_status->stop_after_trap;
3997 stop_soon_quietly = inf_status->stop_soon_quietly;
3998 bpstat_clear (&stop_bpstat);
3999 stop_bpstat = inf_status->stop_bpstat;
4000 breakpoint_proceeded = inf_status->breakpoint_proceeded;
4001 proceed_to_finish = inf_status->proceed_to_finish;
4003 /* FIXME: Is the restore of stop_registers always needed. */
4004 regcache_xfree (stop_registers);
4005 stop_registers = inf_status->stop_registers;
4007 /* The inferior can be gone if the user types "print exit(0)"
4008 (and perhaps other times). */
4009 if (target_has_execution)
4010 /* NB: The register write goes through to the target. */
4011 regcache_cpy (current_regcache, inf_status->registers);
4012 regcache_xfree (inf_status->registers);
4014 /* FIXME: If we are being called after stopping in a function which
4015 is called from gdb, we should not be trying to restore the
4016 selected frame; it just prints a spurious error message (The
4017 message is useful, however, in detecting bugs in gdb (like if gdb
4018 clobbers the stack)). In fact, should we be restoring the
4019 inferior status at all in that case? . */
4021 if (target_has_stack && inf_status->restore_stack_info)
4023 /* The point of catch_errors is that if the stack is clobbered,
4024 walking the stack might encounter a garbage pointer and
4025 error() trying to dereference it. */
4027 (restore_selected_frame, &inf_status->selected_frame_id,
4028 "Unable to restore previously selected frame:\n",
4029 RETURN_MASK_ERROR) == 0)
4030 /* Error in restoring the selected frame. Select the innermost
4032 select_frame (get_current_frame ());
4040 do_restore_inferior_status_cleanup (void *sts)
4042 restore_inferior_status (sts);
4046 make_cleanup_restore_inferior_status (struct inferior_status *inf_status)
4048 return make_cleanup (do_restore_inferior_status_cleanup, inf_status);
4052 discard_inferior_status (struct inferior_status *inf_status)
4054 /* See save_inferior_status for info on stop_bpstat. */
4055 bpstat_clear (&inf_status->stop_bpstat);
4056 regcache_xfree (inf_status->registers);
4057 regcache_xfree (inf_status->stop_registers);
4061 /* Oft used ptids */
4063 ptid_t minus_one_ptid;
4065 /* Create a ptid given the necessary PID, LWP, and TID components. */
4068 ptid_build (int pid, long lwp, long tid)
4078 /* Create a ptid from just a pid. */
4081 pid_to_ptid (int pid)
4083 return ptid_build (pid, 0, 0);
4086 /* Fetch the pid (process id) component from a ptid. */
4089 ptid_get_pid (ptid_t ptid)
4094 /* Fetch the lwp (lightweight process) component from a ptid. */
4097 ptid_get_lwp (ptid_t ptid)
4102 /* Fetch the tid (thread id) component from a ptid. */
4105 ptid_get_tid (ptid_t ptid)
4110 /* ptid_equal() is used to test equality of two ptids. */
4113 ptid_equal (ptid_t ptid1, ptid_t ptid2)
4115 return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp
4116 && ptid1.tid == ptid2.tid);
4119 /* restore_inferior_ptid() will be used by the cleanup machinery
4120 to restore the inferior_ptid value saved in a call to
4121 save_inferior_ptid(). */
4124 restore_inferior_ptid (void *arg)
4126 ptid_t *saved_ptid_ptr = arg;
4127 inferior_ptid = *saved_ptid_ptr;
4131 /* Save the value of inferior_ptid so that it may be restored by a
4132 later call to do_cleanups(). Returns the struct cleanup pointer
4133 needed for later doing the cleanup. */
4136 save_inferior_ptid (void)
4138 ptid_t *saved_ptid_ptr;
4140 saved_ptid_ptr = xmalloc (sizeof (ptid_t));
4141 *saved_ptid_ptr = inferior_ptid;
4142 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
4149 stop_registers = regcache_xmalloc (current_gdbarch);
4153 _initialize_infrun (void)
4156 register int numsigs;
4157 struct cmd_list_element *c;
4159 register_gdbarch_swap (&stop_registers, sizeof (stop_registers), NULL);
4160 register_gdbarch_swap (NULL, 0, build_infrun);
4162 add_info ("signals", signals_info,
4163 "What debugger does when program gets various signals.\n\
4164 Specify a signal as argument to print info on that signal only.");
4165 add_info_alias ("handle", "signals", 0);
4167 add_com ("handle", class_run, handle_command,
4168 concat ("Specify how to handle a signal.\n\
4169 Args are signals and actions to apply to those signals.\n\
4170 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4171 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4172 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4173 The special arg \"all\" is recognized to mean all signals except those\n\
4174 used by the debugger, typically SIGTRAP and SIGINT.\n", "Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4175 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4176 Stop means reenter debugger if this signal happens (implies print).\n\
4177 Print means print a message if this signal happens.\n\
4178 Pass means let program see this signal; otherwise program doesn't know.\n\
4179 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4180 Pass and Stop may be combined.", NULL));
4183 add_com ("lz", class_info, signals_info,
4184 "What debugger does when program gets various signals.\n\
4185 Specify a signal as argument to print info on that signal only.");
4186 add_com ("z", class_run, xdb_handle_command,
4187 concat ("Specify how to handle a signal.\n\
4188 Args are signals and actions to apply to those signals.\n\
4189 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4190 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4191 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4192 The special arg \"all\" is recognized to mean all signals except those\n\
4193 used by the debugger, typically SIGTRAP and SIGINT.\n", "Recognized actions include \"s\" (toggles between stop and nostop), \n\
4194 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4195 nopass), \"Q\" (noprint)\n\
4196 Stop means reenter debugger if this signal happens (implies print).\n\
4197 Print means print a message if this signal happens.\n\
4198 Pass means let program see this signal; otherwise program doesn't know.\n\
4199 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4200 Pass and Stop may be combined.", NULL));
4205 add_cmd ("stop", class_obscure, not_just_help_class_command, "There is no `stop' command, but you can set a hook on `stop'.\n\
4206 This allows you to set a list of commands to be run each time execution\n\
4207 of the program stops.", &cmdlist);
4209 numsigs = (int) TARGET_SIGNAL_LAST;
4210 signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
4211 signal_print = (unsigned char *)
4212 xmalloc (sizeof (signal_print[0]) * numsigs);
4213 signal_program = (unsigned char *)
4214 xmalloc (sizeof (signal_program[0]) * numsigs);
4215 for (i = 0; i < numsigs; i++)
4218 signal_print[i] = 1;
4219 signal_program[i] = 1;
4222 /* Signals caused by debugger's own actions
4223 should not be given to the program afterwards. */
4224 signal_program[TARGET_SIGNAL_TRAP] = 0;
4225 signal_program[TARGET_SIGNAL_INT] = 0;
4227 /* Signals that are not errors should not normally enter the debugger. */
4228 signal_stop[TARGET_SIGNAL_ALRM] = 0;
4229 signal_print[TARGET_SIGNAL_ALRM] = 0;
4230 signal_stop[TARGET_SIGNAL_VTALRM] = 0;
4231 signal_print[TARGET_SIGNAL_VTALRM] = 0;
4232 signal_stop[TARGET_SIGNAL_PROF] = 0;
4233 signal_print[TARGET_SIGNAL_PROF] = 0;
4234 signal_stop[TARGET_SIGNAL_CHLD] = 0;
4235 signal_print[TARGET_SIGNAL_CHLD] = 0;
4236 signal_stop[TARGET_SIGNAL_IO] = 0;
4237 signal_print[TARGET_SIGNAL_IO] = 0;
4238 signal_stop[TARGET_SIGNAL_POLL] = 0;
4239 signal_print[TARGET_SIGNAL_POLL] = 0;
4240 signal_stop[TARGET_SIGNAL_URG] = 0;
4241 signal_print[TARGET_SIGNAL_URG] = 0;
4242 signal_stop[TARGET_SIGNAL_WINCH] = 0;
4243 signal_print[TARGET_SIGNAL_WINCH] = 0;
4245 /* These signals are used internally by user-level thread
4246 implementations. (See signal(5) on Solaris.) Like the above
4247 signals, a healthy program receives and handles them as part of
4248 its normal operation. */
4249 signal_stop[TARGET_SIGNAL_LWP] = 0;
4250 signal_print[TARGET_SIGNAL_LWP] = 0;
4251 signal_stop[TARGET_SIGNAL_WAITING] = 0;
4252 signal_print[TARGET_SIGNAL_WAITING] = 0;
4253 signal_stop[TARGET_SIGNAL_CANCEL] = 0;
4254 signal_print[TARGET_SIGNAL_CANCEL] = 0;
4258 (add_set_cmd ("stop-on-solib-events", class_support, var_zinteger,
4259 (char *) &stop_on_solib_events,
4260 "Set stopping for shared library events.\n\
4261 If nonzero, gdb will give control to the user when the dynamic linker\n\
4262 notifies gdb of shared library events. The most common event of interest\n\
4263 to the user would be loading/unloading of a new library.\n", &setlist), &showlist);
4266 c = add_set_enum_cmd ("follow-fork-mode",
4268 follow_fork_mode_kind_names, &follow_fork_mode_string,
4269 /* ??rehrauer: The "both" option is broken, by what may be a 10.20
4270 kernel problem. It's also not terribly useful without a GUI to
4271 help the user drive two debuggers. So for now, I'm disabling
4272 the "both" option. */
4273 /* "Set debugger response to a program call of fork \
4275 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4276 parent - the original process is debugged after a fork\n\
4277 child - the new process is debugged after a fork\n\
4278 both - both the parent and child are debugged after a fork\n\
4279 ask - the debugger will ask for one of the above choices\n\
4280 For \"both\", another copy of the debugger will be started to follow\n\
4281 the new child process. The original debugger will continue to follow\n\
4282 the original parent process. To distinguish their prompts, the\n\
4283 debugger copy's prompt will be changed.\n\
4284 For \"parent\" or \"child\", the unfollowed process will run free.\n\
4285 By default, the debugger will follow the parent process.",
4287 "Set debugger response to a program call of fork \
4289 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4290 parent - the original process is debugged after a fork\n\
4291 child - the new process is debugged after a fork\n\
4292 ask - the debugger will ask for one of the above choices\n\
4293 For \"parent\" or \"child\", the unfollowed process will run free.\n\
4294 By default, the debugger will follow the parent process.", &setlist);
4295 add_show_from_set (c, &showlist);
4297 c = add_set_enum_cmd ("scheduler-locking", class_run, scheduler_enums, /* array of string names */
4298 &scheduler_mode, /* current mode */
4299 "Set mode for locking scheduler during execution.\n\
4300 off == no locking (threads may preempt at any time)\n\
4301 on == full locking (no thread except the current thread may run)\n\
4302 step == scheduler locked during every single-step operation.\n\
4303 In this mode, no other thread may run during a step command.\n\
4304 Other threads may run while stepping over a function call ('next').", &setlist);
4306 set_cmd_sfunc (c, set_schedlock_func); /* traps on target vector */
4307 add_show_from_set (c, &showlist);
4309 c = add_set_cmd ("step-mode", class_run,
4310 var_boolean, (char *) &step_stop_if_no_debug,
4311 "Set mode of the step operation. When set, doing a step over a\n\
4312 function without debug line information will stop at the first\n\
4313 instruction of that function. Otherwise, the function is skipped and\n\
4314 the step command stops at a different source line.", &setlist);
4315 add_show_from_set (c, &showlist);
4317 /* ptid initializations */
4318 null_ptid = ptid_build (0, 0, 0);
4319 minus_one_ptid = ptid_build (-1, 0, 0);
4320 inferior_ptid = null_ptid;
4321 target_last_wait_ptid = minus_one_ptid;