1 /* Target-struct-independent code to start (run) and stop an inferior process.
2 Copyright 1986-1989, 1991-1999 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 #include "gdb_string.h"
27 #include "breakpoint.h"
32 #include "gdbthread.h"
34 #include "symfile.h" /* for overlay functions */
39 /* Prototypes for local functions */
41 static void signals_info (char *, int);
43 static void handle_command (char *, int);
45 static void sig_print_info (enum target_signal);
47 static void sig_print_header (void);
49 static void resume_cleanups (int);
51 static int hook_stop_stub (void *);
53 static void delete_breakpoint_current_contents (void *);
55 static void set_follow_fork_mode_command (char *arg, int from_tty,
56 struct cmd_list_element * c);
58 static struct inferior_status *xmalloc_inferior_status (void);
60 static void free_inferior_status (struct inferior_status *);
62 static int restore_selected_frame (void *);
64 static void build_infrun (void);
66 static void follow_inferior_fork (int parent_pid, int child_pid,
67 int has_forked, int has_vforked);
69 static void follow_fork (int parent_pid, int child_pid);
71 static void follow_vfork (int parent_pid, int child_pid);
73 static void set_schedlock_func (char *args, int from_tty,
74 struct cmd_list_element * c);
76 struct execution_control_state;
78 static int currently_stepping (struct execution_control_state *ecs);
80 static void xdb_handle_command (char *args, int from_tty);
82 void _initialize_infrun (void);
84 int inferior_ignoring_startup_exec_events = 0;
85 int inferior_ignoring_leading_exec_events = 0;
87 /* In asynchronous mode, but simulating synchronous execution. */
89 int sync_execution = 0;
91 /* wait_for_inferior and normal_stop use this to notify the user
92 when the inferior stopped in a different thread than it had been
95 static int previous_inferior_pid;
97 /* This is true for configurations that may follow through execl() and
98 similar functions. At present this is only true for HP-UX native. */
100 #ifndef MAY_FOLLOW_EXEC
101 #define MAY_FOLLOW_EXEC (0)
104 static int may_follow_exec = MAY_FOLLOW_EXEC;
106 /* resume and wait_for_inferior use this to ensure that when
107 stepping over a hit breakpoint in a threaded application
108 only the thread that hit the breakpoint is stepped and the
109 other threads don't continue. This prevents having another
110 thread run past the breakpoint while it is temporarily
113 This is not thread-specific, so it isn't saved as part of
116 Versions of gdb which don't use the "step == this thread steps
117 and others continue" model but instead use the "step == this
118 thread steps and others wait" shouldn't do this. */
120 static int thread_step_needed = 0;
122 /* This is true if thread_step_needed should actually be used. At
123 present this is only true for HP-UX native. */
125 #ifndef USE_THREAD_STEP_NEEDED
126 #define USE_THREAD_STEP_NEEDED (0)
129 static int use_thread_step_needed = USE_THREAD_STEP_NEEDED;
131 /* GET_LONGJMP_TARGET returns the PC at which longjmp() will resume the
132 program. It needs to examine the jmp_buf argument and extract the PC
133 from it. The return value is non-zero on success, zero otherwise. */
135 #ifndef GET_LONGJMP_TARGET
136 #define GET_LONGJMP_TARGET(PC_ADDR) 0
140 /* Some machines have trampoline code that sits between function callers
141 and the actual functions themselves. If this machine doesn't have
142 such things, disable their processing. */
144 #ifndef SKIP_TRAMPOLINE_CODE
145 #define SKIP_TRAMPOLINE_CODE(pc) 0
148 /* Dynamic function trampolines are similar to solib trampolines in that they
149 are between the caller and the callee. The difference is that when you
150 enter a dynamic trampoline, you can't determine the callee's address. Some
151 (usually complex) code needs to run in the dynamic trampoline to figure out
152 the callee's address. This macro is usually called twice. First, when we
153 enter the trampoline (looks like a normal function call at that point). It
154 should return the PC of a point within the trampoline where the callee's
155 address is known. Second, when we hit the breakpoint, this routine returns
156 the callee's address. At that point, things proceed as per a step resume
159 #ifndef DYNAMIC_TRAMPOLINE_NEXTPC
160 #define DYNAMIC_TRAMPOLINE_NEXTPC(pc) 0
163 /* If the program uses ELF-style shared libraries, then calls to
164 functions in shared libraries go through stubs, which live in a
165 table called the PLT (Procedure Linkage Table). The first time the
166 function is called, the stub sends control to the dynamic linker,
167 which looks up the function's real address, patches the stub so
168 that future calls will go directly to the function, and then passes
169 control to the function.
171 If we are stepping at the source level, we don't want to see any of
172 this --- we just want to skip over the stub and the dynamic linker.
173 The simple approach is to single-step until control leaves the
176 However, on some systems (e.g., Red Hat Linux 5.2) the dynamic
177 linker calls functions in the shared C library, so you can't tell
178 from the PC alone whether the dynamic linker is still running. In
179 this case, we use a step-resume breakpoint to get us past the
180 dynamic linker, as if we were using "next" to step over a function
183 IN_SOLIB_DYNSYM_RESOLVE_CODE says whether we're in the dynamic
184 linker code or not. Normally, this means we single-step. However,
185 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
186 address where we can place a step-resume breakpoint to get past the
187 linker's symbol resolution function.
189 IN_SOLIB_DYNSYM_RESOLVE_CODE can generally be implemented in a
190 pretty portable way, by comparing the PC against the address ranges
191 of the dynamic linker's sections.
193 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
194 it depends on internal details of the dynamic linker. It's usually
195 not too hard to figure out where to put a breakpoint, but it
196 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
197 sanity checking. If it can't figure things out, returning zero and
198 getting the (possibly confusing) stepping behavior is better than
199 signalling an error, which will obscure the change in the
202 #ifndef IN_SOLIB_DYNSYM_RESOLVE_CODE
203 #define IN_SOLIB_DYNSYM_RESOLVE_CODE(pc) 0
206 #ifndef SKIP_SOLIB_RESOLVER
207 #define SKIP_SOLIB_RESOLVER(pc) 0
210 /* For SVR4 shared libraries, each call goes through a small piece of
211 trampoline code in the ".plt" section. IN_SOLIB_CALL_TRAMPOLINE evaluates
212 to nonzero if we are current stopped in one of these. */
214 #ifndef IN_SOLIB_CALL_TRAMPOLINE
215 #define IN_SOLIB_CALL_TRAMPOLINE(pc,name) 0
218 /* In some shared library schemes, the return path from a shared library
219 call may need to go through a trampoline too. */
221 #ifndef IN_SOLIB_RETURN_TRAMPOLINE
222 #define IN_SOLIB_RETURN_TRAMPOLINE(pc,name) 0
225 /* This function returns TRUE if pc is the address of an instruction
226 that lies within the dynamic linker (such as the event hook, or the
229 This function must be used only when a dynamic linker event has
230 been caught, and the inferior is being stepped out of the hook, or
231 undefined results are guaranteed. */
233 #ifndef SOLIB_IN_DYNAMIC_LINKER
234 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
237 /* On MIPS16, a function that returns a floating point value may call
238 a library helper function to copy the return value to a floating point
239 register. The IGNORE_HELPER_CALL macro returns non-zero if we
240 should ignore (i.e. step over) this function call. */
241 #ifndef IGNORE_HELPER_CALL
242 #define IGNORE_HELPER_CALL(pc) 0
245 /* On some systems, the PC may be left pointing at an instruction that won't
246 actually be executed. This is usually indicated by a bit in the PSW. If
247 we find ourselves in such a state, then we step the target beyond the
248 nullified instruction before returning control to the user so as to avoid
251 #ifndef INSTRUCTION_NULLIFIED
252 #define INSTRUCTION_NULLIFIED 0
255 /* We can't step off a permanent breakpoint in the ordinary way, because we
256 can't remove it. Instead, we have to advance the PC to the next
257 instruction. This macro should expand to a pointer to a function that
258 does that, or zero if we have no such function. If we don't have a
259 definition for it, we have to report an error. */
260 #ifndef SKIP_PERMANENT_BREAKPOINT
261 #define SKIP_PERMANENT_BREAKPOINT (default_skip_permanent_breakpoint)
263 default_skip_permanent_breakpoint (void)
266 fprintf_filtered (gdb_stderr, "\
267 The program is stopped at a permanent breakpoint, but GDB does not know\n\
268 how to step past a permanent breakpoint on this architecture. Try using\n\
269 a command like `return' or `jump' to continue execution.\n");
270 return_to_top_level (RETURN_ERROR);
275 /* Convert the #defines into values. This is temporary until wfi control
276 flow is completely sorted out. */
278 #ifndef HAVE_STEPPABLE_WATCHPOINT
279 #define HAVE_STEPPABLE_WATCHPOINT 0
281 #undef HAVE_STEPPABLE_WATCHPOINT
282 #define HAVE_STEPPABLE_WATCHPOINT 1
285 #ifndef HAVE_NONSTEPPABLE_WATCHPOINT
286 #define HAVE_NONSTEPPABLE_WATCHPOINT 0
288 #undef HAVE_NONSTEPPABLE_WATCHPOINT
289 #define HAVE_NONSTEPPABLE_WATCHPOINT 1
292 #ifndef HAVE_CONTINUABLE_WATCHPOINT
293 #define HAVE_CONTINUABLE_WATCHPOINT 0
295 #undef HAVE_CONTINUABLE_WATCHPOINT
296 #define HAVE_CONTINUABLE_WATCHPOINT 1
299 /* Tables of how to react to signals; the user sets them. */
301 static unsigned char *signal_stop;
302 static unsigned char *signal_print;
303 static unsigned char *signal_program;
305 #define SET_SIGS(nsigs,sigs,flags) \
307 int signum = (nsigs); \
308 while (signum-- > 0) \
309 if ((sigs)[signum]) \
310 (flags)[signum] = 1; \
313 #define UNSET_SIGS(nsigs,sigs,flags) \
315 int signum = (nsigs); \
316 while (signum-- > 0) \
317 if ((sigs)[signum]) \
318 (flags)[signum] = 0; \
322 /* Command list pointer for the "stop" placeholder. */
324 static struct cmd_list_element *stop_command;
326 /* Nonzero if breakpoints are now inserted in the inferior. */
328 static int breakpoints_inserted;
330 /* Function inferior was in as of last step command. */
332 static struct symbol *step_start_function;
334 /* Nonzero if we are expecting a trace trap and should proceed from it. */
336 static int trap_expected;
339 /* Nonzero if we want to give control to the user when we're notified
340 of shared library events by the dynamic linker. */
341 static int stop_on_solib_events;
345 /* Nonzero if the next time we try to continue the inferior, it will
346 step one instruction and generate a spurious trace trap.
347 This is used to compensate for a bug in HP-UX. */
349 static int trap_expected_after_continue;
352 /* Nonzero means expecting a trace trap
353 and should stop the inferior and return silently when it happens. */
357 /* Nonzero means expecting a trap and caller will handle it themselves.
358 It is used after attach, due to attaching to a process;
359 when running in the shell before the child program has been exec'd;
360 and when running some kinds of remote stuff (FIXME?). */
362 int stop_soon_quietly;
364 /* Nonzero if proceed is being used for a "finish" command or a similar
365 situation when stop_registers should be saved. */
367 int proceed_to_finish;
369 /* Save register contents here when about to pop a stack dummy frame,
370 if-and-only-if proceed_to_finish is set.
371 Thus this contains the return value from the called function (assuming
372 values are returned in a register). */
374 char *stop_registers;
376 /* Nonzero if program stopped due to error trying to insert breakpoints. */
378 static int breakpoints_failed;
380 /* Nonzero after stop if current stack frame should be printed. */
382 static int stop_print_frame;
384 static struct breakpoint *step_resume_breakpoint = NULL;
385 static struct breakpoint *through_sigtramp_breakpoint = NULL;
387 /* On some platforms (e.g., HP-UX), hardware watchpoints have bad
388 interactions with an inferior that is running a kernel function
389 (aka, a system call or "syscall"). wait_for_inferior therefore
390 may have a need to know when the inferior is in a syscall. This
391 is a count of the number of inferior threads which are known to
392 currently be running in a syscall. */
393 static int number_of_threads_in_syscalls;
395 /* This is used to remember when a fork, vfork or exec event
396 was caught by a catchpoint, and thus the event is to be
397 followed at the next resume of the inferior, and not
401 enum target_waitkind kind;
411 char *execd_pathname;
415 /* Some platforms don't allow us to do anything meaningful with a
416 vforked child until it has exec'd. Vforked processes on such
417 platforms can only be followed after they've exec'd.
419 When this is set to 0, a vfork can be immediately followed,
420 and an exec can be followed merely as an exec. When this is
421 set to 1, a vfork event has been seen, but cannot be followed
422 until the exec is seen.
424 (In the latter case, inferior_pid is still the parent of the
425 vfork, and pending_follow.fork_event.child_pid is the child. The
426 appropriate process is followed, according to the setting of
427 follow-fork-mode.) */
428 static int follow_vfork_when_exec;
430 static char *follow_fork_mode_kind_names[] =
432 /* ??rehrauer: The "both" option is broken, by what may be a 10.20
433 kernel problem. It's also not terribly useful without a GUI to
434 help the user drive two debuggers. So for now, I'm disabling
436 "parent", "child", "both", "ask" };
438 "parent", "child", "ask"};
440 static char *follow_fork_mode_string = NULL;
444 follow_inferior_fork (int parent_pid, int child_pid, int has_forked,
447 int followed_parent = 0;
448 int followed_child = 0;
450 /* Which process did the user want us to follow? */
452 savestring (follow_fork_mode_string, strlen (follow_fork_mode_string));
454 /* Or, did the user not know, and want us to ask? */
455 if (STREQ (follow_fork_mode_string, "ask"))
457 char requested_mode[100];
460 error ("\"ask\" mode NYI");
461 follow_mode = savestring (requested_mode, strlen (requested_mode));
464 /* If we're to be following the parent, then detach from child_pid.
465 We're already following the parent, so need do nothing explicit
467 if (STREQ (follow_mode, "parent"))
471 /* We're already attached to the parent, by default. */
473 /* Before detaching from the child, remove all breakpoints from
474 it. (This won't actually modify the breakpoint list, but will
475 physically remove the breakpoints from the child.) */
476 if (!has_vforked || !follow_vfork_when_exec)
478 detach_breakpoints (child_pid);
479 #ifdef SOLIB_REMOVE_INFERIOR_HOOK
480 SOLIB_REMOVE_INFERIOR_HOOK (child_pid);
484 /* Detach from the child. */
487 target_require_detach (child_pid, "", 1);
490 /* If we're to be following the child, then attach to it, detach
491 from inferior_pid, and set inferior_pid to child_pid. */
492 else if (STREQ (follow_mode, "child"))
494 char child_pid_spelling[100]; /* Arbitrary length. */
498 /* Before detaching from the parent, detach all breakpoints from
499 the child. But only if we're forking, or if we follow vforks
500 as soon as they happen. (If we're following vforks only when
501 the child has exec'd, then it's very wrong to try to write
502 back the "shadow contents" of inserted breakpoints now -- they
503 belong to the child's pre-exec'd a.out.) */
504 if (!has_vforked || !follow_vfork_when_exec)
506 detach_breakpoints (child_pid);
509 /* Before detaching from the parent, remove all breakpoints from it. */
510 remove_breakpoints ();
512 /* Also reset the solib inferior hook from the parent. */
513 #ifdef SOLIB_REMOVE_INFERIOR_HOOK
514 SOLIB_REMOVE_INFERIOR_HOOK (inferior_pid);
517 /* Detach from the parent. */
519 target_detach (NULL, 1);
521 /* Attach to the child. */
522 inferior_pid = child_pid;
523 sprintf (child_pid_spelling, "%d", child_pid);
526 target_require_attach (child_pid_spelling, 1);
528 /* Was there a step_resume breakpoint? (There was if the user
529 did a "next" at the fork() call.) If so, explicitly reset its
532 step_resumes are a form of bp that are made to be per-thread.
533 Since we created the step_resume bp when the parent process
534 was being debugged, and now are switching to the child process,
535 from the breakpoint package's viewpoint, that's a switch of
536 "threads". We must update the bp's notion of which thread
537 it is for, or it'll be ignored when it triggers... */
538 if (step_resume_breakpoint &&
539 (!has_vforked || !follow_vfork_when_exec))
540 breakpoint_re_set_thread (step_resume_breakpoint);
542 /* Reinsert all breakpoints in the child. (The user may've set
543 breakpoints after catching the fork, in which case those
544 actually didn't get set in the child, but only in the parent.) */
545 if (!has_vforked || !follow_vfork_when_exec)
547 breakpoint_re_set ();
548 insert_breakpoints ();
552 /* If we're to be following both parent and child, then fork ourselves,
553 and attach the debugger clone to the child. */
554 else if (STREQ (follow_mode, "both"))
556 char pid_suffix[100]; /* Arbitrary length. */
558 /* Clone ourselves to follow the child. This is the end of our
559 involvement with child_pid; our clone will take it from here... */
561 target_clone_and_follow_inferior (child_pid, &followed_child);
562 followed_parent = !followed_child;
564 /* We continue to follow the parent. To help distinguish the two
565 debuggers, though, both we and our clone will reset our prompts. */
566 sprintf (pid_suffix, "[%d] ", inferior_pid);
567 set_prompt (strcat (get_prompt (), pid_suffix));
570 /* The parent and child of a vfork share the same address space.
571 Also, on some targets the order in which vfork and exec events
572 are received for parent in child requires some delicate handling
575 For instance, on ptrace-based HPUX we receive the child's vfork
576 event first, at which time the parent has been suspended by the
577 OS and is essentially untouchable until the child's exit or second
578 exec event arrives. At that time, the parent's vfork event is
579 delivered to us, and that's when we see and decide how to follow
580 the vfork. But to get to that point, we must continue the child
581 until it execs or exits. To do that smoothly, all breakpoints
582 must be removed from the child, in case there are any set between
583 the vfork() and exec() calls. But removing them from the child
584 also removes them from the parent, due to the shared-address-space
585 nature of a vfork'd parent and child. On HPUX, therefore, we must
586 take care to restore the bp's to the parent before we continue it.
587 Else, it's likely that we may not stop in the expected place. (The
588 worst scenario is when the user tries to step over a vfork() call;
589 the step-resume bp must be restored for the step to properly stop
590 in the parent after the call completes!)
592 Sequence of events, as reported to gdb from HPUX:
594 Parent Child Action for gdb to take
595 -------------------------------------------------------
596 1 VFORK Continue child
602 target_post_follow_vfork (parent_pid,
608 pending_follow.fork_event.saw_parent_fork = 0;
609 pending_follow.fork_event.saw_child_fork = 0;
615 follow_fork (int parent_pid, int child_pid)
617 follow_inferior_fork (parent_pid, child_pid, 1, 0);
621 /* Forward declaration. */
622 static void follow_exec (int, char *);
625 follow_vfork (int parent_pid, int child_pid)
627 follow_inferior_fork (parent_pid, child_pid, 0, 1);
629 /* Did we follow the child? Had it exec'd before we saw the parent vfork? */
630 if (pending_follow.fork_event.saw_child_exec && (inferior_pid == child_pid))
632 pending_follow.fork_event.saw_child_exec = 0;
633 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
634 follow_exec (inferior_pid, pending_follow.execd_pathname);
635 free (pending_follow.execd_pathname);
640 follow_exec (int pid, char *execd_pathname)
643 struct target_ops *tgt;
645 if (!may_follow_exec)
648 /* Did this exec() follow a vfork()? If so, we must follow the
649 vfork now too. Do it before following the exec. */
650 if (follow_vfork_when_exec &&
651 (pending_follow.kind == TARGET_WAITKIND_VFORKED))
653 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
654 follow_vfork (inferior_pid, pending_follow.fork_event.child_pid);
655 follow_vfork_when_exec = 0;
656 saved_pid = inferior_pid;
658 /* Did we follow the parent? If so, we're done. If we followed
659 the child then we must also follow its exec(). */
660 if (inferior_pid == pending_follow.fork_event.parent_pid)
664 /* This is an exec event that we actually wish to pay attention to.
665 Refresh our symbol table to the newly exec'd program, remove any
668 If there are breakpoints, they aren't really inserted now,
669 since the exec() transformed our inferior into a fresh set
672 We want to preserve symbolic breakpoints on the list, since
673 we have hopes that they can be reset after the new a.out's
674 symbol table is read.
676 However, any "raw" breakpoints must be removed from the list
677 (e.g., the solib bp's), since their address is probably invalid
680 And, we DON'T want to call delete_breakpoints() here, since
681 that may write the bp's "shadow contents" (the instruction
682 value that was overwritten witha TRAP instruction). Since
683 we now have a new a.out, those shadow contents aren't valid. */
684 update_breakpoints_after_exec ();
686 /* If there was one, it's gone now. We cannot truly step-to-next
687 statement through an exec(). */
688 step_resume_breakpoint = NULL;
689 step_range_start = 0;
692 /* If there was one, it's gone now. */
693 through_sigtramp_breakpoint = NULL;
695 /* What is this a.out's name? */
696 printf_unfiltered ("Executing new program: %s\n", execd_pathname);
698 /* We've followed the inferior through an exec. Therefore, the
699 inferior has essentially been killed & reborn. */
701 /* First collect the run target in effect. */
702 tgt = find_run_target ();
703 /* If we can't find one, things are in a very strange state... */
705 error ("Could find run target to save before following exec");
707 gdb_flush (gdb_stdout);
708 target_mourn_inferior ();
709 inferior_pid = saved_pid; /* Because mourn_inferior resets inferior_pid. */
712 /* That a.out is now the one to use. */
713 exec_file_attach (execd_pathname, 0);
715 /* And also is where symbols can be found. */
716 symbol_file_command (execd_pathname, 0);
718 /* Reset the shared library package. This ensures that we get
719 a shlib event when the child reaches "_start", at which point
720 the dld will have had a chance to initialize the child. */
721 #if defined(SOLIB_RESTART)
724 #ifdef SOLIB_CREATE_INFERIOR_HOOK
725 SOLIB_CREATE_INFERIOR_HOOK (inferior_pid);
728 /* Reinsert all breakpoints. (Those which were symbolic have
729 been reset to the proper address in the new a.out, thanks
730 to symbol_file_command...) */
731 insert_breakpoints ();
733 /* The next resume of this inferior should bring it to the shlib
734 startup breakpoints. (If the user had also set bp's on
735 "main" from the old (parent) process, then they'll auto-
736 matically get reset there in the new process.) */
739 /* Non-zero if we just simulating a single-step. This is needed
740 because we cannot remove the breakpoints in the inferior process
741 until after the `wait' in `wait_for_inferior'. */
742 static int singlestep_breakpoints_inserted_p = 0;
745 /* Things to clean up if we QUIT out of resume (). */
748 resume_cleanups (int arg)
753 static char schedlock_off[] = "off";
754 static char schedlock_on[] = "on";
755 static char schedlock_step[] = "step";
756 static char *scheduler_mode = schedlock_off;
757 static char *scheduler_enums[] =
758 {schedlock_off, schedlock_on, schedlock_step};
761 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
763 if (c->type == set_cmd)
764 if (!target_can_lock_scheduler)
766 scheduler_mode = schedlock_off;
767 error ("Target '%s' cannot support this command.",
775 /* Resume the inferior, but allow a QUIT. This is useful if the user
776 wants to interrupt some lengthy single-stepping operation
777 (for child processes, the SIGINT goes to the inferior, and so
778 we get a SIGINT random_signal, but for remote debugging and perhaps
779 other targets, that's not true).
781 STEP nonzero if we should step (zero to continue instead).
782 SIG is the signal to give the inferior (zero for none). */
784 resume (int step, enum target_signal sig)
786 int should_resume = 1;
787 struct cleanup *old_cleanups = make_cleanup ((make_cleanup_func)
791 #ifdef CANNOT_STEP_BREAKPOINT
792 /* Most targets can step a breakpoint instruction, thus executing it
793 normally. But if this one cannot, just continue and we will hit
795 if (step && breakpoints_inserted && breakpoint_here_p (read_pc ()))
799 /* Normally, by the time we reach `resume', the breakpoints are either
800 removed or inserted, as appropriate. The exception is if we're sitting
801 at a permanent breakpoint; we need to step over it, but permanent
802 breakpoints can't be removed. So we have to test for it here. */
803 if (breakpoint_here_p (read_pc ()) == permanent_breakpoint_here)
804 SKIP_PERMANENT_BREAKPOINT ();
806 if (SOFTWARE_SINGLE_STEP_P && step)
808 /* Do it the hard way, w/temp breakpoints */
809 SOFTWARE_SINGLE_STEP (sig, 1 /*insert-breakpoints */ );
810 /* ...and don't ask hardware to do it. */
812 /* and do not pull these breakpoints until after a `wait' in
813 `wait_for_inferior' */
814 singlestep_breakpoints_inserted_p = 1;
817 /* Handle any optimized stores to the inferior NOW... */
818 #ifdef DO_DEFERRED_STORES
822 /* If there were any forks/vforks/execs that were caught and are
823 now to be followed, then do so. */
824 switch (pending_follow.kind)
826 case (TARGET_WAITKIND_FORKED):
827 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
828 follow_fork (inferior_pid, pending_follow.fork_event.child_pid);
831 case (TARGET_WAITKIND_VFORKED):
833 int saw_child_exec = pending_follow.fork_event.saw_child_exec;
835 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
836 follow_vfork (inferior_pid, pending_follow.fork_event.child_pid);
838 /* Did we follow the child, but not yet see the child's exec event?
839 If so, then it actually ought to be waiting for us; we respond to
840 parent vfork events. We don't actually want to resume the child
841 in this situation; we want to just get its exec event. */
842 if (!saw_child_exec &&
843 (inferior_pid == pending_follow.fork_event.child_pid))
848 case (TARGET_WAITKIND_EXECD):
849 /* If we saw a vfork event but couldn't follow it until we saw
850 an exec, then now might be the time! */
851 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
852 /* follow_exec is called as soon as the exec event is seen. */
859 /* Install inferior's terminal modes. */
860 target_terminal_inferior ();
864 if (use_thread_step_needed && thread_step_needed)
866 /* We stopped on a BPT instruction;
867 don't continue other threads and
868 just step this thread. */
869 thread_step_needed = 0;
871 if (!breakpoint_here_p (read_pc ()))
873 /* Breakpoint deleted: ok to do regular resume
874 where all the threads either step or continue. */
875 target_resume (-1, step, sig);
881 warning ("Internal error, changing continue to step.");
882 remove_breakpoints ();
883 breakpoints_inserted = 0;
888 target_resume (inferior_pid, step, sig);
893 /* Vanilla resume. */
895 if ((scheduler_mode == schedlock_on) ||
896 (scheduler_mode == schedlock_step && step != 0))
897 target_resume (inferior_pid, step, sig);
899 target_resume (-1, step, sig);
903 discard_cleanups (old_cleanups);
907 /* Clear out all variables saying what to do when inferior is continued.
908 First do this, then set the ones you want, then call `proceed'. */
911 clear_proceed_status (void)
914 step_range_start = 0;
916 step_frame_address = 0;
917 step_over_calls = -1;
919 stop_soon_quietly = 0;
920 proceed_to_finish = 0;
921 breakpoint_proceeded = 1; /* We're about to proceed... */
923 /* Discard any remaining commands or status from previous stop. */
924 bpstat_clear (&stop_bpstat);
927 /* Basic routine for continuing the program in various fashions.
929 ADDR is the address to resume at, or -1 for resume where stopped.
930 SIGGNAL is the signal to give it, or 0 for none,
931 or -1 for act according to how it stopped.
932 STEP is nonzero if should trap after one instruction.
933 -1 means return after that and print nothing.
934 You should probably set various step_... variables
935 before calling here, if you are stepping.
937 You should call clear_proceed_status before calling proceed. */
940 proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
945 step_start_function = find_pc_function (read_pc ());
949 if (addr == (CORE_ADDR) -1)
951 /* If there is a breakpoint at the address we will resume at,
952 step one instruction before inserting breakpoints
953 so that we do not stop right away (and report a second
954 hit at this breakpoint). */
956 if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
959 #ifndef STEP_SKIPS_DELAY
960 #define STEP_SKIPS_DELAY(pc) (0)
961 #define STEP_SKIPS_DELAY_P (0)
963 /* Check breakpoint_here_p first, because breakpoint_here_p is fast
964 (it just checks internal GDB data structures) and STEP_SKIPS_DELAY
965 is slow (it needs to read memory from the target). */
966 if (STEP_SKIPS_DELAY_P
967 && breakpoint_here_p (read_pc () + 4)
968 && STEP_SKIPS_DELAY (read_pc ()))
975 /* New address; we don't need to single-step a thread
976 over a breakpoint we just hit, 'cause we aren't
977 continuing from there.
979 It's not worth worrying about the case where a user
980 asks for a "jump" at the current PC--if they get the
981 hiccup of re-hiting a hit breakpoint, what else do
983 thread_step_needed = 0;
986 #ifdef PREPARE_TO_PROCEED
987 /* In a multi-threaded task we may select another thread
988 and then continue or step.
990 But if the old thread was stopped at a breakpoint, it
991 will immediately cause another breakpoint stop without
992 any execution (i.e. it will report a breakpoint hit
993 incorrectly). So we must step over it first.
995 PREPARE_TO_PROCEED checks the current thread against the thread
996 that reported the most recent event. If a step-over is required
997 it returns TRUE and sets the current thread to the old thread. */
998 if (PREPARE_TO_PROCEED (1) && breakpoint_here_p (read_pc ()))
1001 thread_step_needed = 1;
1004 #endif /* PREPARE_TO_PROCEED */
1007 if (trap_expected_after_continue)
1009 /* If (step == 0), a trap will be automatically generated after
1010 the first instruction is executed. Force step one
1011 instruction to clear this condition. This should not occur
1012 if step is nonzero, but it is harmless in that case. */
1014 trap_expected_after_continue = 0;
1016 #endif /* HP_OS_BUG */
1019 /* We will get a trace trap after one instruction.
1020 Continue it automatically and insert breakpoints then. */
1024 int temp = insert_breakpoints ();
1027 print_sys_errmsg ("ptrace", temp);
1028 error ("Cannot insert breakpoints.\n\
1029 The same program may be running in another process.");
1032 breakpoints_inserted = 1;
1035 if (siggnal != TARGET_SIGNAL_DEFAULT)
1036 stop_signal = siggnal;
1037 /* If this signal should not be seen by program,
1038 give it zero. Used for debugging signals. */
1039 else if (!signal_program[stop_signal])
1040 stop_signal = TARGET_SIGNAL_0;
1042 annotate_starting ();
1044 /* Make sure that output from GDB appears before output from the
1046 gdb_flush (gdb_stdout);
1048 /* Resume inferior. */
1049 resume (oneproc || step || bpstat_should_step (), stop_signal);
1051 /* Wait for it to stop (if not standalone)
1052 and in any case decode why it stopped, and act accordingly. */
1053 /* Do this only if we are not using the event loop, or if the target
1054 does not support asynchronous execution. */
1055 if (!event_loop_p || !target_can_async_p ())
1057 wait_for_inferior ();
1062 /* Record the pc and sp of the program the last time it stopped.
1063 These are just used internally by wait_for_inferior, but need
1064 to be preserved over calls to it and cleared when the inferior
1066 static CORE_ADDR prev_pc;
1067 static CORE_ADDR prev_func_start;
1068 static char *prev_func_name;
1071 /* Start remote-debugging of a machine over a serial link. */
1076 init_thread_list ();
1077 init_wait_for_inferior ();
1078 stop_soon_quietly = 1;
1081 /* Always go on waiting for the target, regardless of the mode. */
1082 /* FIXME: cagney/1999-09-23: At present it isn't possible to
1083 indicate th wait_for_inferior that a target should timeout if
1084 nothing is returned (instead of just blocking). Because of this,
1085 targets expecting an immediate response need to, internally, set
1086 things up so that the target_wait() is forced to eventually
1088 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1089 differentiate to its caller what the state of the target is after
1090 the initial open has been performed. Here we're assuming that
1091 the target has stopped. It should be possible to eventually have
1092 target_open() return to the caller an indication that the target
1093 is currently running and GDB state should be set to the same as
1094 for an async run. */
1095 wait_for_inferior ();
1099 /* Initialize static vars when a new inferior begins. */
1102 init_wait_for_inferior (void)
1104 /* These are meaningless until the first time through wait_for_inferior. */
1106 prev_func_start = 0;
1107 prev_func_name = NULL;
1110 trap_expected_after_continue = 0;
1112 breakpoints_inserted = 0;
1113 breakpoint_init_inferior (inf_starting);
1115 /* Don't confuse first call to proceed(). */
1116 stop_signal = TARGET_SIGNAL_0;
1118 /* The first resume is not following a fork/vfork/exec. */
1119 pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
1120 pending_follow.fork_event.saw_parent_fork = 0;
1121 pending_follow.fork_event.saw_child_fork = 0;
1122 pending_follow.fork_event.saw_child_exec = 0;
1124 /* See wait_for_inferior's handling of SYSCALL_ENTRY/RETURN events. */
1125 number_of_threads_in_syscalls = 0;
1127 clear_proceed_status ();
1131 delete_breakpoint_current_contents (void *arg)
1133 struct breakpoint **breakpointp = (struct breakpoint **) arg;
1134 if (*breakpointp != NULL)
1136 delete_breakpoint (*breakpointp);
1137 *breakpointp = NULL;
1141 /* This enum encodes possible reasons for doing a target_wait, so that
1142 wfi can call target_wait in one place. (Ultimately the call will be
1143 moved out of the infinite loop entirely.) */
1147 infwait_normal_state,
1148 infwait_thread_hop_state,
1149 infwait_nullified_state,
1150 infwait_nonstep_watch_state
1153 /* Why did the inferior stop? Used to print the appropriate messages
1154 to the interface from within handle_inferior_event(). */
1155 enum inferior_stop_reason
1157 /* We don't know why. */
1159 /* Step, next, nexti, stepi finished. */
1161 /* Found breakpoint. */
1163 /* Inferior terminated by signal. */
1165 /* Inferior exited. */
1167 /* Inferior received signal, and user asked to be notified. */
1171 /* This structure contains what used to be local variables in
1172 wait_for_inferior. Probably many of them can return to being
1173 locals in handle_inferior_event. */
1175 struct execution_control_state
1177 struct target_waitstatus ws;
1178 struct target_waitstatus *wp;
1181 CORE_ADDR stop_func_start;
1182 CORE_ADDR stop_func_end;
1183 char *stop_func_name;
1184 struct symtab_and_line sal;
1185 int remove_breakpoints_on_following_step;
1187 struct symtab *current_symtab;
1188 int handling_longjmp; /* FIXME */
1190 int saved_inferior_pid;
1192 int stepping_through_solib_after_catch;
1193 bpstat stepping_through_solib_catchpoints;
1194 int enable_hw_watchpoints_after_wait;
1195 int stepping_through_sigtramp;
1196 int new_thread_event;
1197 struct target_waitstatus tmpstatus;
1198 enum infwait_states infwait_state;
1203 void init_execution_control_state (struct execution_control_state * ecs);
1205 void handle_inferior_event (struct execution_control_state * ecs);
1207 static void check_sigtramp2 (struct execution_control_state *ecs);
1208 static void step_into_function (struct execution_control_state *ecs);
1209 static void step_over_function (struct execution_control_state *ecs);
1210 static void stop_stepping (struct execution_control_state *ecs);
1211 static void prepare_to_wait (struct execution_control_state *ecs);
1212 static void keep_going (struct execution_control_state *ecs);
1213 static void print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info);
1215 /* Wait for control to return from inferior to debugger.
1216 If inferior gets a signal, we may decide to start it up again
1217 instead of returning. That is why there is a loop in this function.
1218 When this function actually returns it means the inferior
1219 should be left stopped and GDB should read more commands. */
1222 wait_for_inferior (void)
1224 struct cleanup *old_cleanups;
1225 struct execution_control_state ecss;
1226 struct execution_control_state *ecs;
1228 old_cleanups = make_cleanup (delete_breakpoint_current_contents,
1229 &step_resume_breakpoint);
1230 make_cleanup (delete_breakpoint_current_contents,
1231 &through_sigtramp_breakpoint);
1233 /* wfi still stays in a loop, so it's OK just to take the address of
1234 a local to get the ecs pointer. */
1237 /* Fill in with reasonable starting values. */
1238 init_execution_control_state (ecs);
1240 thread_step_needed = 0;
1242 /* We'll update this if & when we switch to a new thread. */
1243 previous_inferior_pid = inferior_pid;
1245 overlay_cache_invalid = 1;
1247 /* We have to invalidate the registers BEFORE calling target_wait
1248 because they can be loaded from the target while in target_wait.
1249 This makes remote debugging a bit more efficient for those
1250 targets that provide critical registers as part of their normal
1251 status mechanism. */
1253 registers_changed ();
1257 if (target_wait_hook)
1258 ecs->pid = target_wait_hook (ecs->waiton_pid, ecs->wp);
1260 ecs->pid = target_wait (ecs->waiton_pid, ecs->wp);
1262 /* Now figure out what to do with the result of the result. */
1263 handle_inferior_event (ecs);
1265 if (!ecs->wait_some_more)
1268 do_cleanups (old_cleanups);
1271 /* Asynchronous version of wait_for_inferior. It is called by the
1272 event loop whenever a change of state is detected on the file
1273 descriptor corresponding to the target. It can be called more than
1274 once to complete a single execution command. In such cases we need
1275 to keep the state in a global variable ASYNC_ECSS. If it is the
1276 last time that this function is called for a single execution
1277 command, then report to the user that the inferior has stopped, and
1278 do the necessary cleanups. */
1280 struct execution_control_state async_ecss;
1281 struct execution_control_state *async_ecs;
1284 fetch_inferior_event (client_data)
1287 static struct cleanup *old_cleanups;
1289 async_ecs = &async_ecss;
1291 if (!async_ecs->wait_some_more)
1293 old_cleanups = make_exec_cleanup (delete_breakpoint_current_contents,
1294 &step_resume_breakpoint);
1295 make_exec_cleanup (delete_breakpoint_current_contents,
1296 &through_sigtramp_breakpoint);
1298 /* Fill in with reasonable starting values. */
1299 init_execution_control_state (async_ecs);
1301 thread_step_needed = 0;
1303 /* We'll update this if & when we switch to a new thread. */
1304 previous_inferior_pid = inferior_pid;
1306 overlay_cache_invalid = 1;
1308 /* We have to invalidate the registers BEFORE calling target_wait
1309 because they can be loaded from the target while in target_wait.
1310 This makes remote debugging a bit more efficient for those
1311 targets that provide critical registers as part of their normal
1312 status mechanism. */
1314 registers_changed ();
1317 if (target_wait_hook)
1318 async_ecs->pid = target_wait_hook (async_ecs->waiton_pid, async_ecs->wp);
1320 async_ecs->pid = target_wait (async_ecs->waiton_pid, async_ecs->wp);
1322 /* Now figure out what to do with the result of the result. */
1323 handle_inferior_event (async_ecs);
1325 if (!async_ecs->wait_some_more)
1327 /* Do only the cleanups that have been added by this
1328 function. Let the continuations for the commands do the rest,
1329 if there are any. */
1330 do_exec_cleanups (old_cleanups);
1332 if (step_multi && stop_step)
1333 inferior_event_handler (INF_EXEC_CONTINUE, NULL);
1335 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
1339 /* Prepare an execution control state for looping through a
1340 wait_for_inferior-type loop. */
1343 init_execution_control_state (struct execution_control_state *ecs)
1345 /* ecs->another_trap? */
1346 ecs->random_signal = 0;
1347 ecs->remove_breakpoints_on_following_step = 0;
1348 ecs->handling_longjmp = 0; /* FIXME */
1349 ecs->update_step_sp = 0;
1350 ecs->stepping_through_solib_after_catch = 0;
1351 ecs->stepping_through_solib_catchpoints = NULL;
1352 ecs->enable_hw_watchpoints_after_wait = 0;
1353 ecs->stepping_through_sigtramp = 0;
1354 ecs->sal = find_pc_line (prev_pc, 0);
1355 ecs->current_line = ecs->sal.line;
1356 ecs->current_symtab = ecs->sal.symtab;
1357 ecs->infwait_state = infwait_normal_state;
1358 ecs->waiton_pid = -1;
1359 ecs->wp = &(ecs->ws);
1362 /* Call this function before setting step_resume_breakpoint, as a
1363 sanity check. There should never be more than one step-resume
1364 breakpoint per thread, so we should never be setting a new
1365 step_resume_breakpoint when one is already active. */
1367 check_for_old_step_resume_breakpoint (void)
1369 if (step_resume_breakpoint)
1370 warning ("GDB bug: infrun.c (wait_for_inferior): dropping old step_resume breakpoint");
1373 /* Given an execution control state that has been freshly filled in
1374 by an event from the inferior, figure out what it means and take
1375 appropriate action. */
1378 handle_inferior_event (struct execution_control_state *ecs)
1381 int stepped_after_stopped_by_watchpoint;
1383 /* Keep this extra brace for now, minimizes diffs. */
1385 switch (ecs->infwait_state)
1387 case infwait_normal_state:
1388 /* Since we've done a wait, we have a new event. Don't
1389 carry over any expectations about needing to step over a
1391 thread_step_needed = 0;
1393 /* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
1394 is serviced in this loop, below. */
1395 if (ecs->enable_hw_watchpoints_after_wait)
1397 TARGET_ENABLE_HW_WATCHPOINTS (inferior_pid);
1398 ecs->enable_hw_watchpoints_after_wait = 0;
1400 stepped_after_stopped_by_watchpoint = 0;
1403 case infwait_thread_hop_state:
1404 insert_breakpoints ();
1406 /* We need to restart all the threads now,
1407 * unles we're running in scheduler-locked mode.
1408 * FIXME: shouldn't we look at currently_stepping ()?
1410 if (scheduler_mode == schedlock_on)
1411 target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
1413 target_resume (-1, 0, TARGET_SIGNAL_0);
1414 ecs->infwait_state = infwait_normal_state;
1415 prepare_to_wait (ecs);
1418 case infwait_nullified_state:
1421 case infwait_nonstep_watch_state:
1422 insert_breakpoints ();
1424 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1425 handle things like signals arriving and other things happening
1426 in combination correctly? */
1427 stepped_after_stopped_by_watchpoint = 1;
1430 ecs->infwait_state = infwait_normal_state;
1432 flush_cached_frames ();
1434 /* If it's a new process, add it to the thread database */
1436 ecs->new_thread_event = ((ecs->pid != inferior_pid) && !in_thread_list (ecs->pid));
1438 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
1439 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
1440 && ecs->new_thread_event)
1442 add_thread (ecs->pid);
1444 printf_filtered ("[New %s]\n", target_pid_or_tid_to_str (ecs->pid));
1447 /* NOTE: This block is ONLY meant to be invoked in case of a
1448 "thread creation event"! If it is invoked for any other
1449 sort of event (such as a new thread landing on a breakpoint),
1450 the event will be discarded, which is almost certainly
1453 To avoid this, the low-level module (eg. target_wait)
1454 should call in_thread_list and add_thread, so that the
1455 new thread is known by the time we get here. */
1457 /* We may want to consider not doing a resume here in order
1458 to give the user a chance to play with the new thread.
1459 It might be good to make that a user-settable option. */
1461 /* At this point, all threads are stopped (happens
1462 automatically in either the OS or the native code).
1463 Therefore we need to continue all threads in order to
1466 target_resume (-1, 0, TARGET_SIGNAL_0);
1467 prepare_to_wait (ecs);
1472 switch (ecs->ws.kind)
1474 case TARGET_WAITKIND_LOADED:
1475 /* Ignore gracefully during startup of the inferior, as it
1476 might be the shell which has just loaded some objects,
1477 otherwise add the symbols for the newly loaded objects. */
1479 if (!stop_soon_quietly)
1481 /* Remove breakpoints, SOLIB_ADD might adjust
1482 breakpoint addresses via breakpoint_re_set. */
1483 if (breakpoints_inserted)
1484 remove_breakpoints ();
1486 /* Check for any newly added shared libraries if we're
1487 supposed to be adding them automatically. */
1490 /* Switch terminal for any messages produced by
1491 breakpoint_re_set. */
1492 target_terminal_ours_for_output ();
1493 SOLIB_ADD (NULL, 0, NULL);
1494 target_terminal_inferior ();
1497 /* Reinsert breakpoints and continue. */
1498 if (breakpoints_inserted)
1499 insert_breakpoints ();
1502 resume (0, TARGET_SIGNAL_0);
1503 prepare_to_wait (ecs);
1506 case TARGET_WAITKIND_SPURIOUS:
1507 resume (0, TARGET_SIGNAL_0);
1508 prepare_to_wait (ecs);
1511 case TARGET_WAITKIND_EXITED:
1512 target_terminal_ours (); /* Must do this before mourn anyway */
1513 print_stop_reason (EXITED, ecs->ws.value.integer);
1515 /* Record the exit code in the convenience variable $_exitcode, so
1516 that the user can inspect this again later. */
1517 set_internalvar (lookup_internalvar ("_exitcode"),
1518 value_from_longest (builtin_type_int,
1519 (LONGEST) ecs->ws.value.integer));
1520 gdb_flush (gdb_stdout);
1521 target_mourn_inferior ();
1522 singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P */
1523 stop_print_frame = 0;
1524 stop_stepping (ecs);
1527 case TARGET_WAITKIND_SIGNALLED:
1528 stop_print_frame = 0;
1529 stop_signal = ecs->ws.value.sig;
1530 target_terminal_ours (); /* Must do this before mourn anyway */
1532 /* This looks pretty bogus to me. Doesn't TARGET_WAITKIND_SIGNALLED
1533 mean it is already dead? This has been here since GDB 2.8, so
1534 perhaps it means rms didn't understand unix waitstatuses?
1535 For the moment I'm just kludging around this in remote.c
1536 rather than trying to change it here --kingdon, 5 Dec 1994. */
1537 target_kill (); /* kill mourns as well */
1539 print_stop_reason (SIGNAL_EXITED, stop_signal);
1540 singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P */
1541 stop_stepping (ecs);
1544 /* The following are the only cases in which we keep going;
1545 the above cases end in a continue or goto. */
1546 case TARGET_WAITKIND_FORKED:
1547 stop_signal = TARGET_SIGNAL_TRAP;
1548 pending_follow.kind = ecs->ws.kind;
1550 /* Ignore fork events reported for the parent; we're only
1551 interested in reacting to forks of the child. Note that
1552 we expect the child's fork event to be available if we
1553 waited for it now. */
1554 if (inferior_pid == ecs->pid)
1556 pending_follow.fork_event.saw_parent_fork = 1;
1557 pending_follow.fork_event.parent_pid = ecs->pid;
1558 pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
1559 prepare_to_wait (ecs);
1564 pending_follow.fork_event.saw_child_fork = 1;
1565 pending_follow.fork_event.child_pid = ecs->pid;
1566 pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
1569 stop_pc = read_pc_pid (ecs->pid);
1570 ecs->saved_inferior_pid = inferior_pid;
1571 inferior_pid = ecs->pid;
1572 stop_bpstat = bpstat_stop_status (&stop_pc, currently_stepping (ecs));
1573 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1574 inferior_pid = ecs->saved_inferior_pid;
1575 goto process_event_stop_test;
1577 /* If this a platform which doesn't allow a debugger to touch a
1578 vfork'd inferior until after it exec's, then we'd best keep
1579 our fingers entirely off the inferior, other than continuing
1580 it. This has the unfortunate side-effect that catchpoints
1581 of vforks will be ignored. But since the platform doesn't
1582 allow the inferior be touched at vfork time, there's really
1584 case TARGET_WAITKIND_VFORKED:
1585 stop_signal = TARGET_SIGNAL_TRAP;
1586 pending_follow.kind = ecs->ws.kind;
1588 /* Is this a vfork of the parent? If so, then give any
1589 vfork catchpoints a chance to trigger now. (It's
1590 dangerous to do so if the child canot be touched until
1591 it execs, and the child has not yet exec'd. We probably
1592 should warn the user to that effect when the catchpoint
1594 if (ecs->pid == inferior_pid)
1596 pending_follow.fork_event.saw_parent_fork = 1;
1597 pending_follow.fork_event.parent_pid = ecs->pid;
1598 pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
1601 /* If we've seen the child's vfork event but cannot really touch
1602 the child until it execs, then we must continue the child now.
1603 Else, give any vfork catchpoints a chance to trigger now. */
1606 pending_follow.fork_event.saw_child_fork = 1;
1607 pending_follow.fork_event.child_pid = ecs->pid;
1608 pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
1609 target_post_startup_inferior (pending_follow.fork_event.child_pid);
1610 follow_vfork_when_exec = !target_can_follow_vfork_prior_to_exec ();
1611 if (follow_vfork_when_exec)
1613 target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
1614 prepare_to_wait (ecs);
1619 stop_pc = read_pc ();
1620 stop_bpstat = bpstat_stop_status (&stop_pc, currently_stepping (ecs));
1621 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1622 goto process_event_stop_test;
1624 case TARGET_WAITKIND_EXECD:
1625 stop_signal = TARGET_SIGNAL_TRAP;
1627 /* Is this a target which reports multiple exec events per actual
1628 call to exec()? (HP-UX using ptrace does, for example.) If so,
1629 ignore all but the last one. Just resume the exec'r, and wait
1630 for the next exec event. */
1631 if (inferior_ignoring_leading_exec_events)
1633 inferior_ignoring_leading_exec_events--;
1634 if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
1635 ENSURE_VFORKING_PARENT_REMAINS_STOPPED (pending_follow.fork_event.parent_pid);
1636 target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
1637 prepare_to_wait (ecs);
1640 inferior_ignoring_leading_exec_events =
1641 target_reported_exec_events_per_exec_call () - 1;
1643 pending_follow.execd_pathname =
1644 savestring (ecs->ws.value.execd_pathname,
1645 strlen (ecs->ws.value.execd_pathname));
1647 /* Did inferior_pid exec, or did a (possibly not-yet-followed)
1648 child of a vfork exec?
1650 ??rehrauer: This is unabashedly an HP-UX specific thing. On
1651 HP-UX, events associated with a vforking inferior come in
1652 threes: a vfork event for the child (always first), followed
1653 a vfork event for the parent and an exec event for the child.
1654 The latter two can come in either order.
1656 If we get the parent vfork event first, life's good: We follow
1657 either the parent or child, and then the child's exec event is
1660 But if we get the child's exec event first, then we delay
1661 responding to it until we handle the parent's vfork. Because,
1662 otherwise we can't satisfy a "catch vfork". */
1663 if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
1665 pending_follow.fork_event.saw_child_exec = 1;
1667 /* On some targets, the child must be resumed before
1668 the parent vfork event is delivered. A single-step
1670 if (RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK ())
1671 target_resume (ecs->pid, 1, TARGET_SIGNAL_0);
1672 /* We expect the parent vfork event to be available now. */
1673 prepare_to_wait (ecs);
1677 /* This causes the eventpoints and symbol table to be reset. Must
1678 do this now, before trying to determine whether to stop. */
1679 follow_exec (inferior_pid, pending_follow.execd_pathname);
1680 free (pending_follow.execd_pathname);
1682 stop_pc = read_pc_pid (ecs->pid);
1683 ecs->saved_inferior_pid = inferior_pid;
1684 inferior_pid = ecs->pid;
1685 stop_bpstat = bpstat_stop_status (&stop_pc, currently_stepping (ecs));
1686 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1687 inferior_pid = ecs->saved_inferior_pid;
1688 goto process_event_stop_test;
1690 /* These syscall events are returned on HP-UX, as part of its
1691 implementation of page-protection-based "hardware" watchpoints.
1692 HP-UX has unfortunate interactions between page-protections and
1693 some system calls. Our solution is to disable hardware watches
1694 when a system call is entered, and reenable them when the syscall
1695 completes. The downside of this is that we may miss the precise
1696 point at which a watched piece of memory is modified. "Oh well."
1698 Note that we may have multiple threads running, which may each
1699 enter syscalls at roughly the same time. Since we don't have a
1700 good notion currently of whether a watched piece of memory is
1701 thread-private, we'd best not have any page-protections active
1702 when any thread is in a syscall. Thus, we only want to reenable
1703 hardware watches when no threads are in a syscall.
1705 Also, be careful not to try to gather much state about a thread
1706 that's in a syscall. It's frequently a losing proposition. */
1707 case TARGET_WAITKIND_SYSCALL_ENTRY:
1708 number_of_threads_in_syscalls++;
1709 if (number_of_threads_in_syscalls == 1)
1711 TARGET_DISABLE_HW_WATCHPOINTS (inferior_pid);
1713 resume (0, TARGET_SIGNAL_0);
1714 prepare_to_wait (ecs);
1717 /* Before examining the threads further, step this thread to
1718 get it entirely out of the syscall. (We get notice of the
1719 event when the thread is just on the verge of exiting a
1720 syscall. Stepping one instruction seems to get it back
1723 Note that although the logical place to reenable h/w watches
1724 is here, we cannot. We cannot reenable them before stepping
1725 the thread (this causes the next wait on the thread to hang).
1727 Nor can we enable them after stepping until we've done a wait.
1728 Thus, we simply set the flag ecs->enable_hw_watchpoints_after_wait
1729 here, which will be serviced immediately after the target
1731 case TARGET_WAITKIND_SYSCALL_RETURN:
1732 target_resume (ecs->pid, 1, TARGET_SIGNAL_0);
1734 if (number_of_threads_in_syscalls > 0)
1736 number_of_threads_in_syscalls--;
1737 ecs->enable_hw_watchpoints_after_wait =
1738 (number_of_threads_in_syscalls == 0);
1740 prepare_to_wait (ecs);
1743 case TARGET_WAITKIND_STOPPED:
1744 stop_signal = ecs->ws.value.sig;
1747 /* We had an event in the inferior, but we are not interested
1748 in handling it at this level. The lower layers have already
1749 done what needs to be done, if anything. This case can
1750 occur only when the target is async or extended-async. One
1751 of the circumstamces for this to happen is when the
1752 inferior produces output for the console. The inferior has
1753 not stopped, and we are ignoring the event. */
1754 case TARGET_WAITKIND_IGNORE:
1755 ecs->wait_some_more = 1;
1759 /* We may want to consider not doing a resume here in order to give
1760 the user a chance to play with the new thread. It might be good
1761 to make that a user-settable option. */
1763 /* At this point, all threads are stopped (happens automatically in
1764 either the OS or the native code). Therefore we need to continue
1765 all threads in order to make progress. */
1766 if (ecs->new_thread_event)
1768 target_resume (-1, 0, TARGET_SIGNAL_0);
1769 prepare_to_wait (ecs);
1773 stop_pc = read_pc_pid (ecs->pid);
1775 /* See if a thread hit a thread-specific breakpoint that was meant for
1776 another thread. If so, then step that thread past the breakpoint,
1779 if (stop_signal == TARGET_SIGNAL_TRAP)
1781 if (SOFTWARE_SINGLE_STEP_P && singlestep_breakpoints_inserted_p)
1782 ecs->random_signal = 0;
1783 else if (breakpoints_inserted
1784 && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK))
1786 ecs->random_signal = 0;
1787 if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK,
1792 /* Saw a breakpoint, but it was hit by the wrong thread.
1794 write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, ecs->pid);
1796 remove_status = remove_breakpoints ();
1797 /* Did we fail to remove breakpoints? If so, try
1798 to set the PC past the bp. (There's at least
1799 one situation in which we can fail to remove
1800 the bp's: On HP-UX's that use ttrace, we can't
1801 change the address space of a vforking child
1802 process until the child exits (well, okay, not
1803 then either :-) or execs. */
1804 if (remove_status != 0)
1806 write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK + 4, ecs->pid);
1810 target_resume (ecs->pid, 1, TARGET_SIGNAL_0);
1811 /* FIXME: What if a signal arrives instead of the
1812 single-step happening? */
1814 ecs->waiton_pid = ecs->pid;
1815 ecs->wp = &(ecs->ws);
1816 ecs->infwait_state = infwait_thread_hop_state;
1817 prepare_to_wait (ecs);
1821 /* We need to restart all the threads now,
1822 * unles we're running in scheduler-locked mode.
1823 * FIXME: shouldn't we look at currently_stepping ()?
1825 if (scheduler_mode == schedlock_on)
1826 target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
1828 target_resume (-1, 0, TARGET_SIGNAL_0);
1829 prepare_to_wait (ecs);
1834 /* This breakpoint matches--either it is the right
1835 thread or it's a generic breakpoint for all threads.
1836 Remember that we'll need to step just _this_ thread
1837 on any following user continuation! */
1838 thread_step_needed = 1;
1843 ecs->random_signal = 1;
1845 /* See if something interesting happened to the non-current thread. If
1846 so, then switch to that thread, and eventually give control back to
1849 Note that if there's any kind of pending follow (i.e., of a fork,
1850 vfork or exec), we don't want to do this now. Rather, we'll let
1851 the next resume handle it. */
1852 if ((ecs->pid != inferior_pid) &&
1853 (pending_follow.kind == TARGET_WAITKIND_SPURIOUS))
1857 /* If it's a random signal for a non-current thread, notify user
1858 if he's expressed an interest. */
1859 if (ecs->random_signal
1860 && signal_print[stop_signal])
1862 /* ??rehrauer: I don't understand the rationale for this code. If the
1863 inferior will stop as a result of this signal, then the act of handling
1864 the stop ought to print a message that's couches the stoppage in user
1865 terms, e.g., "Stopped for breakpoint/watchpoint". If the inferior
1866 won't stop as a result of the signal -- i.e., if the signal is merely
1867 a side-effect of something GDB's doing "under the covers" for the
1868 user, such as stepping threads over a breakpoint they shouldn't stop
1869 for -- then the message seems to be a serious annoyance at best.
1871 For now, remove the message altogether. */
1874 target_terminal_ours_for_output ();
1875 printf_filtered ("\nProgram received signal %s, %s.\n",
1876 target_signal_to_name (stop_signal),
1877 target_signal_to_string (stop_signal));
1878 gdb_flush (gdb_stdout);
1882 /* If it's not SIGTRAP and not a signal we want to stop for, then
1883 continue the thread. */
1885 if (stop_signal != TARGET_SIGNAL_TRAP
1886 && !signal_stop[stop_signal])
1889 target_terminal_inferior ();
1891 /* Clear the signal if it should not be passed. */
1892 if (signal_program[stop_signal] == 0)
1893 stop_signal = TARGET_SIGNAL_0;
1895 target_resume (ecs->pid, 0, stop_signal);
1896 prepare_to_wait (ecs);
1900 /* It's a SIGTRAP or a signal we're interested in. Switch threads,
1901 and fall into the rest of wait_for_inferior(). */
1903 /* Caution: it may happen that the new thread (or the old one!)
1904 is not in the thread list. In this case we must not attempt
1905 to "switch context", or we run the risk that our context may
1906 be lost. This may happen as a result of the target module
1907 mishandling thread creation. */
1909 if (in_thread_list (inferior_pid) && in_thread_list (ecs->pid))
1910 { /* Perform infrun state context switch: */
1911 /* Save infrun state for the old thread. */
1912 save_infrun_state (inferior_pid, prev_pc,
1913 prev_func_start, prev_func_name,
1914 trap_expected, step_resume_breakpoint,
1915 through_sigtramp_breakpoint,
1916 step_range_start, step_range_end,
1917 step_frame_address, ecs->handling_longjmp,
1919 ecs->stepping_through_solib_after_catch,
1920 ecs->stepping_through_solib_catchpoints,
1921 ecs->stepping_through_sigtramp);
1923 /* Load infrun state for the new thread. */
1924 load_infrun_state (ecs->pid, &prev_pc,
1925 &prev_func_start, &prev_func_name,
1926 &trap_expected, &step_resume_breakpoint,
1927 &through_sigtramp_breakpoint,
1928 &step_range_start, &step_range_end,
1929 &step_frame_address, &ecs->handling_longjmp,
1931 &ecs->stepping_through_solib_after_catch,
1932 &ecs->stepping_through_solib_catchpoints,
1933 &ecs->stepping_through_sigtramp);
1936 inferior_pid = ecs->pid;
1939 context_hook (pid_to_thread_id (ecs->pid));
1941 flush_cached_frames ();
1944 if (SOFTWARE_SINGLE_STEP_P && singlestep_breakpoints_inserted_p)
1946 /* Pull the single step breakpoints out of the target. */
1947 SOFTWARE_SINGLE_STEP (0, 0);
1948 singlestep_breakpoints_inserted_p = 0;
1951 /* If PC is pointing at a nullified instruction, then step beyond
1952 it so that the user won't be confused when GDB appears to be ready
1955 /* if (INSTRUCTION_NULLIFIED && currently_stepping (ecs)) */
1956 if (INSTRUCTION_NULLIFIED)
1958 registers_changed ();
1959 target_resume (ecs->pid, 1, TARGET_SIGNAL_0);
1961 /* We may have received a signal that we want to pass to
1962 the inferior; therefore, we must not clobber the waitstatus
1965 ecs->infwait_state = infwait_nullified_state;
1966 ecs->waiton_pid = ecs->pid;
1967 ecs->wp = &(ecs->tmpstatus);
1968 prepare_to_wait (ecs);
1972 /* It may not be necessary to disable the watchpoint to stop over
1973 it. For example, the PA can (with some kernel cooperation)
1974 single step over a watchpoint without disabling the watchpoint. */
1975 if (HAVE_STEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
1978 prepare_to_wait (ecs);
1982 /* It is far more common to need to disable a watchpoint to step
1983 the inferior over it. FIXME. What else might a debug
1984 register or page protection watchpoint scheme need here? */
1985 if (HAVE_NONSTEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
1987 /* At this point, we are stopped at an instruction which has
1988 attempted to write to a piece of memory under control of
1989 a watchpoint. The instruction hasn't actually executed
1990 yet. If we were to evaluate the watchpoint expression
1991 now, we would get the old value, and therefore no change
1992 would seem to have occurred.
1994 In order to make watchpoints work `right', we really need
1995 to complete the memory write, and then evaluate the
1996 watchpoint expression. The following code does that by
1997 removing the watchpoint (actually, all watchpoints and
1998 breakpoints), single-stepping the target, re-inserting
1999 watchpoints, and then falling through to let normal
2000 single-step processing handle proceed. Since this
2001 includes evaluating watchpoints, things will come to a
2002 stop in the correct manner. */
2004 write_pc (stop_pc - DECR_PC_AFTER_BREAK);
2006 remove_breakpoints ();
2007 registers_changed ();
2008 target_resume (ecs->pid, 1, TARGET_SIGNAL_0); /* Single step */
2010 ecs->waiton_pid = ecs->pid;
2011 ecs->wp = &(ecs->ws);
2012 ecs->infwait_state = infwait_nonstep_watch_state;
2013 prepare_to_wait (ecs);
2017 /* It may be possible to simply continue after a watchpoint. */
2018 if (HAVE_CONTINUABLE_WATCHPOINT)
2019 STOPPED_BY_WATCHPOINT (ecs->ws);
2021 ecs->stop_func_start = 0;
2022 ecs->stop_func_end = 0;
2023 ecs->stop_func_name = 0;
2024 /* Don't care about return value; stop_func_start and stop_func_name
2025 will both be 0 if it doesn't work. */
2026 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
2027 &ecs->stop_func_start, &ecs->stop_func_end);
2028 ecs->stop_func_start += FUNCTION_START_OFFSET;
2029 ecs->another_trap = 0;
2030 bpstat_clear (&stop_bpstat);
2032 stop_stack_dummy = 0;
2033 stop_print_frame = 1;
2034 ecs->random_signal = 0;
2035 stopped_by_random_signal = 0;
2036 breakpoints_failed = 0;
2038 /* Look at the cause of the stop, and decide what to do.
2039 The alternatives are:
2040 1) break; to really stop and return to the debugger,
2041 2) drop through to start up again
2042 (set ecs->another_trap to 1 to single step once)
2043 3) set ecs->random_signal to 1, and the decision between 1 and 2
2044 will be made according to the signal handling tables. */
2046 /* First, distinguish signals caused by the debugger from signals
2047 that have to do with the program's own actions.
2048 Note that breakpoint insns may cause SIGTRAP or SIGILL
2049 or SIGEMT, depending on the operating system version.
2050 Here we detect when a SIGILL or SIGEMT is really a breakpoint
2051 and change it to SIGTRAP. */
2053 if (stop_signal == TARGET_SIGNAL_TRAP
2054 || (breakpoints_inserted &&
2055 (stop_signal == TARGET_SIGNAL_ILL
2056 || stop_signal == TARGET_SIGNAL_EMT
2058 || stop_soon_quietly)
2060 if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
2062 stop_print_frame = 0;
2063 stop_stepping (ecs);
2066 if (stop_soon_quietly)
2068 stop_stepping (ecs);
2072 /* Don't even think about breakpoints
2073 if just proceeded over a breakpoint.
2075 However, if we are trying to proceed over a breakpoint
2076 and end up in sigtramp, then through_sigtramp_breakpoint
2077 will be set and we should check whether we've hit the
2079 if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected
2080 && through_sigtramp_breakpoint == NULL)
2081 bpstat_clear (&stop_bpstat);
2084 /* See if there is a breakpoint at the current PC. */
2085 stop_bpstat = bpstat_stop_status
2087 /* Pass TRUE if our reason for stopping is something other
2088 than hitting a breakpoint. We do this by checking that
2089 1) stepping is going on and 2) we didn't hit a breakpoint
2090 in a signal handler without an intervening stop in
2091 sigtramp, which is detected by a new stack pointer value
2092 below any usual function calling stack adjustments. */
2093 (currently_stepping (ecs)
2095 && INNER_THAN (read_sp (), (step_sp - 16))))
2097 /* Following in case break condition called a
2099 stop_print_frame = 1;
2102 if (stop_signal == TARGET_SIGNAL_TRAP)
2104 = !(bpstat_explains_signal (stop_bpstat)
2106 || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
2107 && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
2108 FRAME_FP (get_current_frame ())))
2109 || (step_range_end && step_resume_breakpoint == NULL));
2114 = !(bpstat_explains_signal (stop_bpstat)
2115 /* End of a stack dummy. Some systems (e.g. Sony
2116 news) give another signal besides SIGTRAP, so
2117 check here as well as above. */
2118 || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
2119 && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
2120 FRAME_FP (get_current_frame ())))
2122 if (!ecs->random_signal)
2123 stop_signal = TARGET_SIGNAL_TRAP;
2127 /* When we reach this point, we've pretty much decided
2128 that the reason for stopping must've been a random
2129 (unexpected) signal. */
2132 ecs->random_signal = 1;
2133 /* If a fork, vfork or exec event was seen, then there are two
2134 possible responses we can make:
2136 1. If a catchpoint triggers for the event (ecs->random_signal == 0),
2137 then we must stop now and issue a prompt. We will resume
2138 the inferior when the user tells us to.
2139 2. If no catchpoint triggers for the event (ecs->random_signal == 1),
2140 then we must resume the inferior now and keep checking.
2142 In either case, we must take appropriate steps to "follow" the
2143 the fork/vfork/exec when the inferior is resumed. For example,
2144 if follow-fork-mode is "child", then we must detach from the
2145 parent inferior and follow the new child inferior.
2147 In either case, setting pending_follow causes the next resume()
2148 to take the appropriate following action. */
2149 process_event_stop_test:
2150 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
2152 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2155 stop_signal = TARGET_SIGNAL_0;
2160 else if (ecs->ws.kind == TARGET_WAITKIND_VFORKED)
2162 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2164 stop_signal = TARGET_SIGNAL_0;
2169 else if (ecs->ws.kind == TARGET_WAITKIND_EXECD)
2171 pending_follow.kind = ecs->ws.kind;
2172 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2175 stop_signal = TARGET_SIGNAL_0;
2181 /* For the program's own signals, act according to
2182 the signal handling tables. */
2184 if (ecs->random_signal)
2186 /* Signal not for debugging purposes. */
2189 stopped_by_random_signal = 1;
2191 if (signal_print[stop_signal])
2194 target_terminal_ours_for_output ();
2195 print_stop_reason (SIGNAL_RECEIVED, stop_signal);
2197 if (signal_stop[stop_signal])
2199 stop_stepping (ecs);
2202 /* If not going to stop, give terminal back
2203 if we took it away. */
2205 target_terminal_inferior ();
2207 /* Clear the signal if it should not be passed. */
2208 if (signal_program[stop_signal] == 0)
2209 stop_signal = TARGET_SIGNAL_0;
2211 /* I'm not sure whether this needs to be check_sigtramp2 or
2212 whether it could/should be keep_going.
2214 This used to jump to step_over_function if we are stepping,
2217 Suppose the user does a `next' over a function call, and while
2218 that call is in progress, the inferior receives a signal for
2219 which GDB does not stop (i.e., signal_stop[SIG] is false). In
2220 that case, when we reach this point, there is already a
2221 step-resume breakpoint established, right where it should be:
2222 immediately after the function call the user is "next"-ing
2223 over. If we call step_over_function now, two bad things
2226 - we'll create a new breakpoint, at wherever the current
2227 frame's return address happens to be. That could be
2228 anywhere, depending on what function call happens to be on
2229 the top of the stack at that point. Point is, it's probably
2230 not where we need it.
2232 - the existing step-resume breakpoint (which is at the correct
2233 address) will get orphaned: step_resume_breakpoint will point
2234 to the new breakpoint, and the old step-resume breakpoint
2235 will never be cleaned up.
2237 The old behavior was meant to help HP-UX single-step out of
2238 sigtramps. It would place the new breakpoint at prev_pc, which
2239 was certainly wrong. I don't know the details there, so fixing
2240 this probably breaks that. As with anything else, it's up to
2241 the HP-UX maintainer to furnish a fix that doesn't break other
2242 platforms. --JimB, 20 May 1999 */
2243 check_sigtramp2 (ecs);
2246 /* Handle cases caused by hitting a breakpoint. */
2248 CORE_ADDR jmp_buf_pc;
2249 struct bpstat_what what;
2251 what = bpstat_what (stop_bpstat);
2253 if (what.call_dummy)
2255 stop_stack_dummy = 1;
2257 trap_expected_after_continue = 1;
2261 switch (what.main_action)
2263 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
2264 /* If we hit the breakpoint at longjmp, disable it for the
2265 duration of this command. Then, install a temporary
2266 breakpoint at the target of the jmp_buf. */
2267 disable_longjmp_breakpoint ();
2268 remove_breakpoints ();
2269 breakpoints_inserted = 0;
2270 if (!GET_LONGJMP_TARGET (&jmp_buf_pc))
2276 /* Need to blow away step-resume breakpoint, as it
2277 interferes with us */
2278 if (step_resume_breakpoint != NULL)
2280 delete_breakpoint (step_resume_breakpoint);
2281 step_resume_breakpoint = NULL;
2283 /* Not sure whether we need to blow this away too, but probably
2284 it is like the step-resume breakpoint. */
2285 if (through_sigtramp_breakpoint != NULL)
2287 delete_breakpoint (through_sigtramp_breakpoint);
2288 through_sigtramp_breakpoint = NULL;
2292 /* FIXME - Need to implement nested temporary breakpoints */
2293 if (step_over_calls > 0)
2294 set_longjmp_resume_breakpoint (jmp_buf_pc,
2295 get_current_frame ());
2298 set_longjmp_resume_breakpoint (jmp_buf_pc, NULL);
2299 ecs->handling_longjmp = 1; /* FIXME */
2303 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
2304 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
2305 remove_breakpoints ();
2306 breakpoints_inserted = 0;
2308 /* FIXME - Need to implement nested temporary breakpoints */
2310 && (INNER_THAN (FRAME_FP (get_current_frame ()),
2311 step_frame_address)))
2313 ecs->another_trap = 1;
2318 disable_longjmp_breakpoint ();
2319 ecs->handling_longjmp = 0; /* FIXME */
2320 if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
2322 /* else fallthrough */
2324 case BPSTAT_WHAT_SINGLE:
2325 if (breakpoints_inserted)
2327 thread_step_needed = 1;
2328 remove_breakpoints ();
2330 breakpoints_inserted = 0;
2331 ecs->another_trap = 1;
2332 /* Still need to check other stuff, at least the case
2333 where we are stepping and step out of the right range. */
2336 case BPSTAT_WHAT_STOP_NOISY:
2337 stop_print_frame = 1;
2339 /* We are about to nuke the step_resume_breakpoint and
2340 through_sigtramp_breakpoint via the cleanup chain, so
2341 no need to worry about it here. */
2343 stop_stepping (ecs);
2346 case BPSTAT_WHAT_STOP_SILENT:
2347 stop_print_frame = 0;
2349 /* We are about to nuke the step_resume_breakpoint and
2350 through_sigtramp_breakpoint via the cleanup chain, so
2351 no need to worry about it here. */
2353 stop_stepping (ecs);
2356 case BPSTAT_WHAT_STEP_RESUME:
2357 /* This proably demands a more elegant solution, but, yeah
2360 This function's use of the simple variable
2361 step_resume_breakpoint doesn't seem to accomodate
2362 simultaneously active step-resume bp's, although the
2363 breakpoint list certainly can.
2365 If we reach here and step_resume_breakpoint is already
2366 NULL, then apparently we have multiple active
2367 step-resume bp's. We'll just delete the breakpoint we
2368 stopped at, and carry on.
2370 Correction: what the code currently does is delete a
2371 step-resume bp, but it makes no effort to ensure that
2372 the one deleted is the one currently stopped at. MVS */
2374 if (step_resume_breakpoint == NULL)
2376 step_resume_breakpoint =
2377 bpstat_find_step_resume_breakpoint (stop_bpstat);
2379 delete_breakpoint (step_resume_breakpoint);
2380 step_resume_breakpoint = NULL;
2383 case BPSTAT_WHAT_THROUGH_SIGTRAMP:
2384 if (through_sigtramp_breakpoint)
2385 delete_breakpoint (through_sigtramp_breakpoint);
2386 through_sigtramp_breakpoint = NULL;
2388 /* If were waiting for a trap, hitting the step_resume_break
2389 doesn't count as getting it. */
2391 ecs->another_trap = 1;
2394 case BPSTAT_WHAT_CHECK_SHLIBS:
2395 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
2398 /* Remove breakpoints, we eventually want to step over the
2399 shlib event breakpoint, and SOLIB_ADD might adjust
2400 breakpoint addresses via breakpoint_re_set. */
2401 if (breakpoints_inserted)
2402 remove_breakpoints ();
2403 breakpoints_inserted = 0;
2405 /* Check for any newly added shared libraries if we're
2406 supposed to be adding them automatically. */
2409 /* Switch terminal for any messages produced by
2410 breakpoint_re_set. */
2411 target_terminal_ours_for_output ();
2412 SOLIB_ADD (NULL, 0, NULL);
2413 target_terminal_inferior ();
2416 /* Try to reenable shared library breakpoints, additional
2417 code segments in shared libraries might be mapped in now. */
2418 re_enable_breakpoints_in_shlibs ();
2420 /* If requested, stop when the dynamic linker notifies
2421 gdb of events. This allows the user to get control
2422 and place breakpoints in initializer routines for
2423 dynamically loaded objects (among other things). */
2424 if (stop_on_solib_events)
2426 stop_stepping (ecs);
2430 /* If we stopped due to an explicit catchpoint, then the
2431 (see above) call to SOLIB_ADD pulled in any symbols
2432 from a newly-loaded library, if appropriate.
2434 We do want the inferior to stop, but not where it is
2435 now, which is in the dynamic linker callback. Rather,
2436 we would like it stop in the user's program, just after
2437 the call that caused this catchpoint to trigger. That
2438 gives the user a more useful vantage from which to
2439 examine their program's state. */
2440 else if (what.main_action == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
2442 /* ??rehrauer: If I could figure out how to get the
2443 right return PC from here, we could just set a temp
2444 breakpoint and resume. I'm not sure we can without
2445 cracking open the dld's shared libraries and sniffing
2446 their unwind tables and text/data ranges, and that's
2447 not a terribly portable notion.
2449 Until that time, we must step the inferior out of the
2450 dld callback, and also out of the dld itself (and any
2451 code or stubs in libdld.sl, such as "shl_load" and
2452 friends) until we reach non-dld code. At that point,
2453 we can stop stepping. */
2454 bpstat_get_triggered_catchpoints (stop_bpstat,
2455 &ecs->stepping_through_solib_catchpoints);
2456 ecs->stepping_through_solib_after_catch = 1;
2458 /* Be sure to lift all breakpoints, so the inferior does
2459 actually step past this point... */
2460 ecs->another_trap = 1;
2465 /* We want to step over this breakpoint, then keep going. */
2466 ecs->another_trap = 1;
2473 case BPSTAT_WHAT_LAST:
2474 /* Not a real code, but listed here to shut up gcc -Wall. */
2476 case BPSTAT_WHAT_KEEP_CHECKING:
2481 /* We come here if we hit a breakpoint but should not
2482 stop for it. Possibly we also were stepping
2483 and should stop for that. So fall through and
2484 test for stepping. But, if not stepping,
2487 /* Are we stepping to get the inferior out of the dynamic
2488 linker's hook (and possibly the dld itself) after catching
2490 if (ecs->stepping_through_solib_after_catch)
2492 #if defined(SOLIB_ADD)
2493 /* Have we reached our destination? If not, keep going. */
2494 if (SOLIB_IN_DYNAMIC_LINKER (ecs->pid, stop_pc))
2496 ecs->another_trap = 1;
2501 /* Else, stop and report the catchpoint(s) whose triggering
2502 caused us to begin stepping. */
2503 ecs->stepping_through_solib_after_catch = 0;
2504 bpstat_clear (&stop_bpstat);
2505 stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints);
2506 bpstat_clear (&ecs->stepping_through_solib_catchpoints);
2507 stop_print_frame = 1;
2508 stop_stepping (ecs);
2512 if (!CALL_DUMMY_BREAKPOINT_OFFSET_P)
2514 /* This is the old way of detecting the end of the stack dummy.
2515 An architecture which defines CALL_DUMMY_BREAKPOINT_OFFSET gets
2516 handled above. As soon as we can test it on all of them, all
2517 architectures should define it. */
2519 /* If this is the breakpoint at the end of a stack dummy,
2520 just stop silently, unless the user was doing an si/ni, in which
2521 case she'd better know what she's doing. */
2523 if (CALL_DUMMY_HAS_COMPLETED (stop_pc, read_sp (),
2524 FRAME_FP (get_current_frame ()))
2527 stop_print_frame = 0;
2528 stop_stack_dummy = 1;
2530 trap_expected_after_continue = 1;
2532 stop_stepping (ecs);
2537 if (step_resume_breakpoint)
2539 /* Having a step-resume breakpoint overrides anything
2540 else having to do with stepping commands until
2541 that breakpoint is reached. */
2542 /* I'm not sure whether this needs to be check_sigtramp2 or
2543 whether it could/should be keep_going. */
2544 check_sigtramp2 (ecs);
2549 if (step_range_end == 0)
2551 /* Likewise if we aren't even stepping. */
2552 /* I'm not sure whether this needs to be check_sigtramp2 or
2553 whether it could/should be keep_going. */
2554 check_sigtramp2 (ecs);
2559 /* If stepping through a line, keep going if still within it.
2561 Note that step_range_end is the address of the first instruction
2562 beyond the step range, and NOT the address of the last instruction
2564 if (stop_pc >= step_range_start
2565 && stop_pc < step_range_end)
2567 /* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal.
2568 So definately need to check for sigtramp here. */
2569 check_sigtramp2 (ecs);
2574 /* We stepped out of the stepping range. */
2576 /* If we are stepping at the source level and entered the runtime
2577 loader dynamic symbol resolution code, we keep on single stepping
2578 until we exit the run time loader code and reach the callee's
2580 if (step_over_calls < 0 && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc))
2582 CORE_ADDR pc_after_resolver = SKIP_SOLIB_RESOLVER (stop_pc);
2584 if (pc_after_resolver)
2586 /* Set up a step-resume breakpoint at the address
2587 indicated by SKIP_SOLIB_RESOLVER. */
2588 struct symtab_and_line sr_sal;
2590 sr_sal.pc = pc_after_resolver;
2592 check_for_old_step_resume_breakpoint ();
2593 step_resume_breakpoint =
2594 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2595 if (breakpoints_inserted)
2596 insert_breakpoints ();
2603 /* We can't update step_sp every time through the loop, because
2604 reading the stack pointer would slow down stepping too much.
2605 But we can update it every time we leave the step range. */
2606 ecs->update_step_sp = 1;
2608 /* Did we just take a signal? */
2609 if (IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2610 && !IN_SIGTRAMP (prev_pc, prev_func_name)
2611 && INNER_THAN (read_sp (), step_sp))
2613 /* We've just taken a signal; go until we are back to
2614 the point where we took it and one more. */
2616 /* Note: The test above succeeds not only when we stepped
2617 into a signal handler, but also when we step past the last
2618 statement of a signal handler and end up in the return stub
2619 of the signal handler trampoline. To distinguish between
2620 these two cases, check that the frame is INNER_THAN the
2621 previous one below. pai/1997-09-11 */
2625 CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
2627 if (INNER_THAN (current_frame, step_frame_address))
2629 /* We have just taken a signal; go until we are back to
2630 the point where we took it and one more. */
2632 /* This code is needed at least in the following case:
2633 The user types "next" and then a signal arrives (before
2634 the "next" is done). */
2636 /* Note that if we are stopped at a breakpoint, then we need
2637 the step_resume breakpoint to override any breakpoints at
2638 the same location, so that we will still step over the
2639 breakpoint even though the signal happened. */
2640 struct symtab_and_line sr_sal;
2643 sr_sal.symtab = NULL;
2645 sr_sal.pc = prev_pc;
2646 /* We could probably be setting the frame to
2647 step_frame_address; I don't think anyone thought to
2649 check_for_old_step_resume_breakpoint ();
2650 step_resume_breakpoint =
2651 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2652 if (breakpoints_inserted)
2653 insert_breakpoints ();
2657 /* We just stepped out of a signal handler and into
2658 its calling trampoline.
2660 Normally, we'd call step_over_function from
2661 here, but for some reason GDB can't unwind the
2662 stack correctly to find the real PC for the point
2663 user code where the signal trampoline will return
2664 -- FRAME_SAVED_PC fails, at least on HP-UX 10.20.
2665 But signal trampolines are pretty small stubs of
2666 code, anyway, so it's OK instead to just
2667 single-step out. Note: assuming such trampolines
2668 don't exhibit recursion on any platform... */
2669 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
2670 &ecs->stop_func_start,
2671 &ecs->stop_func_end);
2672 /* Readjust stepping range */
2673 step_range_start = ecs->stop_func_start;
2674 step_range_end = ecs->stop_func_end;
2675 ecs->stepping_through_sigtramp = 1;
2680 /* If this is stepi or nexti, make sure that the stepping range
2681 gets us past that instruction. */
2682 if (step_range_end == 1)
2683 /* FIXME: Does this run afoul of the code below which, if
2684 we step into the middle of a line, resets the stepping
2686 step_range_end = (step_range_start = prev_pc) + 1;
2688 ecs->remove_breakpoints_on_following_step = 1;
2693 if (stop_pc == ecs->stop_func_start /* Quick test */
2694 || (in_prologue (stop_pc, ecs->stop_func_start) &&
2695 !IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2696 || IN_SOLIB_CALL_TRAMPOLINE (stop_pc, ecs->stop_func_name)
2697 || ecs->stop_func_name == 0)
2699 /* It's a subroutine call. */
2701 if (step_over_calls == 0)
2703 /* I presume that step_over_calls is only 0 when we're
2704 supposed to be stepping at the assembly language level
2705 ("stepi"). Just stop. */
2707 print_stop_reason (END_STEPPING_RANGE, 0);
2708 stop_stepping (ecs);
2712 if (step_over_calls > 0 || IGNORE_HELPER_CALL (stop_pc))
2714 /* We're doing a "next". */
2715 step_over_function (ecs);
2720 /* If we are in a function call trampoline (a stub between
2721 the calling routine and the real function), locate the real
2722 function. That's what tells us (a) whether we want to step
2723 into it at all, and (b) what prologue we want to run to
2724 the end of, if we do step into it. */
2725 tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
2727 ecs->stop_func_start = tmp;
2730 tmp = DYNAMIC_TRAMPOLINE_NEXTPC (stop_pc);
2733 struct symtab_and_line xxx;
2734 /* Why isn't this s_a_l called "sr_sal", like all of the
2735 other s_a_l's where this code is duplicated? */
2736 INIT_SAL (&xxx); /* initialize to zeroes */
2738 xxx.section = find_pc_overlay (xxx.pc);
2739 check_for_old_step_resume_breakpoint ();
2740 step_resume_breakpoint =
2741 set_momentary_breakpoint (xxx, NULL, bp_step_resume);
2742 insert_breakpoints ();
2748 /* If we have line number information for the function we
2749 are thinking of stepping into, step into it.
2751 If there are several symtabs at that PC (e.g. with include
2752 files), just want to know whether *any* of them have line
2753 numbers. find_pc_line handles this. */
2755 struct symtab_and_line tmp_sal;
2757 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
2758 if (tmp_sal.line != 0)
2760 step_into_function (ecs);
2764 step_over_function (ecs);
2770 /* We've wandered out of the step range. */
2772 ecs->sal = find_pc_line (stop_pc, 0);
2774 if (step_range_end == 1)
2776 /* It is stepi or nexti. We always want to stop stepping after
2779 print_stop_reason (END_STEPPING_RANGE, 0);
2780 stop_stepping (ecs);
2784 /* If we're in the return path from a shared library trampoline,
2785 we want to proceed through the trampoline when stepping. */
2786 if (IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2790 /* Determine where this trampoline returns. */
2791 tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
2793 /* Only proceed through if we know where it's going. */
2796 /* And put the step-breakpoint there and go until there. */
2797 struct symtab_and_line sr_sal;
2799 INIT_SAL (&sr_sal); /* initialize to zeroes */
2801 sr_sal.section = find_pc_overlay (sr_sal.pc);
2802 /* Do not specify what the fp should be when we stop
2803 since on some machines the prologue
2804 is where the new fp value is established. */
2805 check_for_old_step_resume_breakpoint ();
2806 step_resume_breakpoint =
2807 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2808 if (breakpoints_inserted)
2809 insert_breakpoints ();
2811 /* Restart without fiddling with the step ranges or
2818 if (ecs->sal.line == 0)
2820 /* We have no line number information. That means to stop
2821 stepping (does this always happen right after one instruction,
2822 when we do "s" in a function with no line numbers,
2823 or can this happen as a result of a return or longjmp?). */
2825 print_stop_reason (END_STEPPING_RANGE, 0);
2826 stop_stepping (ecs);
2830 if ((stop_pc == ecs->sal.pc)
2831 && (ecs->current_line != ecs->sal.line || ecs->current_symtab != ecs->sal.symtab))
2833 /* We are at the start of a different line. So stop. Note that
2834 we don't stop if we step into the middle of a different line.
2835 That is said to make things like for (;;) statements work
2838 print_stop_reason (END_STEPPING_RANGE, 0);
2839 stop_stepping (ecs);
2843 /* We aren't done stepping.
2845 Optimize by setting the stepping range to the line.
2846 (We might not be in the original line, but if we entered a
2847 new line in mid-statement, we continue stepping. This makes
2848 things like for(;;) statements work better.) */
2850 if (ecs->stop_func_end && ecs->sal.end >= ecs->stop_func_end)
2852 /* If this is the last line of the function, don't keep stepping
2853 (it would probably step us out of the function).
2854 This is particularly necessary for a one-line function,
2855 in which after skipping the prologue we better stop even though
2856 we will be in mid-line. */
2858 print_stop_reason (END_STEPPING_RANGE, 0);
2859 stop_stepping (ecs);
2862 step_range_start = ecs->sal.pc;
2863 step_range_end = ecs->sal.end;
2864 step_frame_address = FRAME_FP (get_current_frame ());
2865 ecs->current_line = ecs->sal.line;
2866 ecs->current_symtab = ecs->sal.symtab;
2868 /* In the case where we just stepped out of a function into the middle
2869 of a line of the caller, continue stepping, but step_frame_address
2870 must be modified to current frame */
2872 CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
2873 if (!(INNER_THAN (current_frame, step_frame_address)))
2874 step_frame_address = current_frame;
2879 } /* extra brace, to preserve old indentation */
2882 /* Are we in the middle of stepping? */
2885 currently_stepping (struct execution_control_state *ecs)
2887 return ((through_sigtramp_breakpoint == NULL
2888 && !ecs->handling_longjmp
2889 && ((step_range_end && step_resume_breakpoint == NULL)
2891 || ecs->stepping_through_solib_after_catch
2892 || bpstat_should_step ());
2896 check_sigtramp2 (struct execution_control_state *ecs)
2899 && IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2900 && !IN_SIGTRAMP (prev_pc, prev_func_name)
2901 && INNER_THAN (read_sp (), step_sp))
2903 /* What has happened here is that we have just stepped the
2904 inferior with a signal (because it is a signal which
2905 shouldn't make us stop), thus stepping into sigtramp.
2907 So we need to set a step_resume_break_address breakpoint and
2908 continue until we hit it, and then step. FIXME: This should
2909 be more enduring than a step_resume breakpoint; we should
2910 know that we will later need to keep going rather than
2911 re-hitting the breakpoint here (see the testsuite,
2912 gdb.base/signals.exp where it says "exceedingly difficult"). */
2914 struct symtab_and_line sr_sal;
2916 INIT_SAL (&sr_sal); /* initialize to zeroes */
2917 sr_sal.pc = prev_pc;
2918 sr_sal.section = find_pc_overlay (sr_sal.pc);
2919 /* We perhaps could set the frame if we kept track of what the
2920 frame corresponding to prev_pc was. But we don't, so don't. */
2921 through_sigtramp_breakpoint =
2922 set_momentary_breakpoint (sr_sal, NULL, bp_through_sigtramp);
2923 if (breakpoints_inserted)
2924 insert_breakpoints ();
2926 ecs->remove_breakpoints_on_following_step = 1;
2927 ecs->another_trap = 1;
2931 /* Subroutine call with source code we should not step over. Do step
2932 to the first line of code in it. */
2935 step_into_function (struct execution_control_state *ecs)
2938 struct symtab_and_line sr_sal;
2940 s = find_pc_symtab (stop_pc);
2941 if (s && s->language != language_asm)
2942 ecs->stop_func_start = SKIP_PROLOGUE (ecs->stop_func_start);
2944 ecs->sal = find_pc_line (ecs->stop_func_start, 0);
2945 /* Use the step_resume_break to step until the end of the prologue,
2946 even if that involves jumps (as it seems to on the vax under
2948 /* If the prologue ends in the middle of a source line, continue to
2949 the end of that source line (if it is still within the function).
2950 Otherwise, just go to end of prologue. */
2951 #ifdef PROLOGUE_FIRSTLINE_OVERLAP
2952 /* no, don't either. It skips any code that's legitimately on the
2956 && ecs->sal.pc != ecs->stop_func_start
2957 && ecs->sal.end < ecs->stop_func_end)
2958 ecs->stop_func_start = ecs->sal.end;
2961 if (ecs->stop_func_start == stop_pc)
2963 /* We are already there: stop now. */
2965 print_stop_reason (END_STEPPING_RANGE, 0);
2966 stop_stepping (ecs);
2971 /* Put the step-breakpoint there and go until there. */
2972 INIT_SAL (&sr_sal); /* initialize to zeroes */
2973 sr_sal.pc = ecs->stop_func_start;
2974 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
2975 /* Do not specify what the fp should be when we stop since on
2976 some machines the prologue is where the new fp value is
2978 check_for_old_step_resume_breakpoint ();
2979 step_resume_breakpoint =
2980 set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2981 if (breakpoints_inserted)
2982 insert_breakpoints ();
2984 /* And make sure stepping stops right away then. */
2985 step_range_end = step_range_start;
2990 /* We've just entered a callee, and we wish to resume until it returns
2991 to the caller. Setting a step_resume breakpoint on the return
2992 address will catch a return from the callee.
2994 However, if the callee is recursing, we want to be careful not to
2995 catch returns of those recursive calls, but only of THIS instance
2998 To do this, we set the step_resume bp's frame to our current
2999 caller's frame (step_frame_address, which is set by the "next" or
3000 "until" command, before execution begins). */
3003 step_over_function (struct execution_control_state *ecs)
3005 struct symtab_and_line sr_sal;
3007 INIT_SAL (&sr_sal); /* initialize to zeros */
3008 sr_sal.pc = ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ()));
3009 sr_sal.section = find_pc_overlay (sr_sal.pc);
3011 check_for_old_step_resume_breakpoint ();
3012 step_resume_breakpoint =
3013 set_momentary_breakpoint (sr_sal, get_current_frame (), bp_step_resume);
3015 if (!IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
3016 step_resume_breakpoint->frame = step_frame_address;
3018 if (breakpoints_inserted)
3019 insert_breakpoints ();
3023 stop_stepping (struct execution_control_state *ecs)
3025 if (target_has_execution)
3027 /* Are we stopping for a vfork event? We only stop when we see
3028 the child's event. However, we may not yet have seen the
3029 parent's event. And, inferior_pid is still set to the
3030 parent's pid, until we resume again and follow either the
3033 To ensure that we can really touch inferior_pid (aka, the
3034 parent process) -- which calls to functions like read_pc
3035 implicitly do -- wait on the parent if necessary. */
3036 if ((pending_follow.kind == TARGET_WAITKIND_VFORKED)
3037 && !pending_follow.fork_event.saw_parent_fork)
3043 if (target_wait_hook)
3044 parent_pid = target_wait_hook (-1, &(ecs->ws));
3046 parent_pid = target_wait (-1, &(ecs->ws));
3048 while (parent_pid != inferior_pid);
3051 /* Assuming the inferior still exists, set these up for next
3052 time, just like we did above if we didn't break out of the
3054 prev_pc = read_pc ();
3055 prev_func_start = ecs->stop_func_start;
3056 prev_func_name = ecs->stop_func_name;
3059 /* Let callers know we don't want to wait for the inferior anymore. */
3060 ecs->wait_some_more = 0;
3063 /* This function handles various cases where we need to continue
3064 waiting for the inferior. */
3065 /* (Used to be the keep_going: label in the old wait_for_inferior) */
3068 keep_going (struct execution_control_state *ecs)
3070 /* ??rehrauer: ttrace on HP-UX theoretically allows one to debug a
3071 vforked child between its creation and subsequent exit or call to
3072 exec(). However, I had big problems in this rather creaky exec
3073 engine, getting that to work. The fundamental problem is that
3074 I'm trying to debug two processes via an engine that only
3075 understands a single process with possibly multiple threads.
3077 Hence, this spot is known to have problems when
3078 target_can_follow_vfork_prior_to_exec returns 1. */
3080 /* Save the pc before execution, to compare with pc after stop. */
3081 prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
3082 prev_func_start = ecs->stop_func_start; /* Ok, since if DECR_PC_AFTER
3083 BREAK is defined, the
3084 original pc would not have
3085 been at the start of a
3087 prev_func_name = ecs->stop_func_name;
3089 if (ecs->update_step_sp)
3090 step_sp = read_sp ();
3091 ecs->update_step_sp = 0;
3093 /* If we did not do break;, it means we should keep running the
3094 inferior and not return to debugger. */
3096 if (trap_expected && stop_signal != TARGET_SIGNAL_TRAP)
3098 /* We took a signal (which we are supposed to pass through to
3099 the inferior, else we'd have done a break above) and we
3100 haven't yet gotten our trap. Simply continue. */
3101 resume (currently_stepping (ecs), stop_signal);
3105 /* Either the trap was not expected, but we are continuing
3106 anyway (the user asked that this signal be passed to the
3109 The signal was SIGTRAP, e.g. it was our signal, but we
3110 decided we should resume from it.
3112 We're going to run this baby now!
3114 Insert breakpoints now, unless we are trying to one-proceed
3115 past a breakpoint. */
3116 /* If we've just finished a special step resume and we don't
3117 want to hit a breakpoint, pull em out. */
3118 if (step_resume_breakpoint == NULL
3119 && through_sigtramp_breakpoint == NULL
3120 && ecs->remove_breakpoints_on_following_step)
3122 ecs->remove_breakpoints_on_following_step = 0;
3123 remove_breakpoints ();
3124 breakpoints_inserted = 0;
3126 else if (!breakpoints_inserted &&
3127 (through_sigtramp_breakpoint != NULL || !ecs->another_trap))
3129 breakpoints_failed = insert_breakpoints ();
3130 if (breakpoints_failed)
3132 stop_stepping (ecs);
3135 breakpoints_inserted = 1;
3138 trap_expected = ecs->another_trap;
3140 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3141 specifies that such a signal should be delivered to the
3144 Typically, this would occure when a user is debugging a
3145 target monitor on a simulator: the target monitor sets a
3146 breakpoint; the simulator encounters this break-point and
3147 halts the simulation handing control to GDB; GDB, noteing
3148 that the break-point isn't valid, returns control back to the
3149 simulator; the simulator then delivers the hardware
3150 equivalent of a SIGNAL_TRAP to the program being debugged. */
3152 if (stop_signal == TARGET_SIGNAL_TRAP
3153 && !signal_program[stop_signal])
3154 stop_signal = TARGET_SIGNAL_0;
3156 #ifdef SHIFT_INST_REGS
3157 /* I'm not sure when this following segment applies. I do know,
3158 now, that we shouldn't rewrite the regs when we were stopped
3159 by a random signal from the inferior process. */
3160 /* FIXME: Shouldn't this be based on the valid bit of the SXIP?
3161 (this is only used on the 88k). */
3163 if (!bpstat_explains_signal (stop_bpstat)
3164 && (stop_signal != TARGET_SIGNAL_CHLD)
3165 && !stopped_by_random_signal)
3167 #endif /* SHIFT_INST_REGS */
3169 resume (currently_stepping (ecs), stop_signal);
3172 prepare_to_wait (ecs);
3175 /* This function normally comes after a resume, before
3176 handle_inferior_event exits. It takes care of any last bits of
3177 housekeeping, and sets the all-important wait_some_more flag. */
3180 prepare_to_wait (struct execution_control_state *ecs)
3182 if (ecs->infwait_state == infwait_normal_state)
3184 overlay_cache_invalid = 1;
3186 /* We have to invalidate the registers BEFORE calling
3187 target_wait because they can be loaded from the target while
3188 in target_wait. This makes remote debugging a bit more
3189 efficient for those targets that provide critical registers
3190 as part of their normal status mechanism. */
3192 registers_changed ();
3193 ecs->waiton_pid = -1;
3194 ecs->wp = &(ecs->ws);
3196 /* This is the old end of the while loop. Let everybody know we
3197 want to wait for the inferior some more and get called again
3199 ecs->wait_some_more = 1;
3202 /* Print why the inferior has stopped. We always print something when
3203 the inferior exits, or receives a signal. The rest of the cases are
3204 dealt with later on in normal_stop() and print_it_typical(). Ideally
3205 there should be a call to this function from handle_inferior_event()
3206 each time stop_stepping() is called.*/
3208 print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
3210 switch (stop_reason)
3213 /* We don't deal with these cases from handle_inferior_event()
3216 case END_STEPPING_RANGE:
3217 /* We are done with a step/next/si/ni command. */
3218 /* For now print nothing. */
3220 case BREAKPOINT_HIT:
3221 /* We found a breakpoint. */
3222 /* For now print nothing. */
3225 /* The inferior was terminated by a signal. */
3226 annotate_signalled ();
3227 printf_filtered ("\nProgram terminated with signal ");
3228 annotate_signal_name ();
3229 printf_filtered ("%s", target_signal_to_name (stop_info));
3230 annotate_signal_name_end ();
3231 printf_filtered (", ");
3232 annotate_signal_string ();
3233 printf_filtered ("%s", target_signal_to_string (stop_info));
3234 annotate_signal_string_end ();
3235 printf_filtered (".\n");
3237 printf_filtered ("The program no longer exists.\n");
3238 gdb_flush (gdb_stdout);
3241 /* The inferior program is finished. */
3242 annotate_exited (stop_info);
3244 printf_filtered ("\nProgram exited with code 0%o.\n",
3245 (unsigned int) stop_info);
3247 printf_filtered ("\nProgram exited normally.\n");
3249 case SIGNAL_RECEIVED:
3250 /* Signal received. The signal table tells us to print about
3253 printf_filtered ("\nProgram received signal ");
3254 annotate_signal_name ();
3255 printf_filtered ("%s", target_signal_to_name (stop_info));
3256 annotate_signal_name_end ();
3257 printf_filtered (", ");
3258 annotate_signal_string ();
3259 printf_filtered ("%s", target_signal_to_string (stop_info));
3260 annotate_signal_string_end ();
3261 printf_filtered (".\n");
3262 gdb_flush (gdb_stdout);
3265 internal_error ("print_stop_reason: unrecognized enum value");
3271 /* Here to return control to GDB when the inferior stops for real.
3272 Print appropriate messages, remove breakpoints, give terminal our modes.
3274 STOP_PRINT_FRAME nonzero means print the executing frame
3275 (pc, function, args, file, line number and line text).
3276 BREAKPOINTS_FAILED nonzero means stop was due to error
3277 attempting to insert breakpoints. */
3282 /* As with the notification of thread events, we want to delay
3283 notifying the user that we've switched thread context until
3284 the inferior actually stops.
3286 (Note that there's no point in saying anything if the inferior
3288 if ((previous_inferior_pid != inferior_pid)
3289 && target_has_execution)
3291 target_terminal_ours_for_output ();
3292 printf_filtered ("[Switching to %s]\n",
3293 target_pid_or_tid_to_str (inferior_pid));
3294 previous_inferior_pid = inferior_pid;
3297 /* Make sure that the current_frame's pc is correct. This
3298 is a correction for setting up the frame info before doing
3299 DECR_PC_AFTER_BREAK */
3300 if (target_has_execution && get_current_frame ())
3301 (get_current_frame ())->pc = read_pc ();
3303 if (breakpoints_failed)
3305 target_terminal_ours_for_output ();
3306 print_sys_errmsg ("ptrace", breakpoints_failed);
3307 printf_filtered ("Stopped; cannot insert breakpoints.\n\
3308 The same program may be running in another process.\n");
3311 if (target_has_execution && breakpoints_inserted)
3313 if (remove_breakpoints ())
3315 target_terminal_ours_for_output ();
3316 printf_filtered ("Cannot remove breakpoints because ");
3317 printf_filtered ("program is no longer writable.\n");
3318 printf_filtered ("It might be running in another process.\n");
3319 printf_filtered ("Further execution is probably impossible.\n");
3322 breakpoints_inserted = 0;
3324 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3325 Delete any breakpoint that is to be deleted at the next stop. */
3327 breakpoint_auto_delete (stop_bpstat);
3329 /* If an auto-display called a function and that got a signal,
3330 delete that auto-display to avoid an infinite recursion. */
3332 if (stopped_by_random_signal)
3333 disable_current_display ();
3335 /* Don't print a message if in the middle of doing a "step n"
3336 operation for n > 1 */
3337 if (step_multi && stop_step)
3340 target_terminal_ours ();
3342 /* Look up the hook_stop and run it if it exists. */
3344 if (stop_command && stop_command->hook)
3346 catch_errors (hook_stop_stub, stop_command->hook,
3347 "Error while running hook_stop:\n", RETURN_MASK_ALL);
3350 if (!target_has_stack)
3356 /* Select innermost stack frame - i.e., current frame is frame 0,
3357 and current location is based on that.
3358 Don't do this on return from a stack dummy routine,
3359 or if the program has exited. */
3361 if (!stop_stack_dummy)
3363 select_frame (get_current_frame (), 0);
3365 /* Print current location without a level number, if
3366 we have changed functions or hit a breakpoint.
3367 Print source line if we have one.
3368 bpstat_print() contains the logic deciding in detail
3369 what to print, based on the event(s) that just occurred. */
3371 if (stop_print_frame)
3375 int do_frame_printing = 1;
3377 bpstat_ret = bpstat_print (stop_bpstat);
3382 && step_frame_address == FRAME_FP (get_current_frame ())
3383 && step_start_function == find_pc_function (stop_pc))
3384 source_flag = -1; /* finished step, just print source line */
3386 source_flag = 1; /* print location and source line */
3388 case PRINT_SRC_AND_LOC:
3389 source_flag = 1; /* print location and source line */
3391 case PRINT_SRC_ONLY:
3395 do_frame_printing = 0;
3398 internal_error ("Unknown value.");
3401 /* The behavior of this routine with respect to the source
3403 -1: Print only source line
3404 0: Print only location
3405 1: Print location and source line */
3406 if (do_frame_printing)
3407 show_and_print_stack_frame (selected_frame, -1, source_flag);
3409 /* Display the auto-display expressions. */
3414 /* Save the function value return registers, if we care.
3415 We might be about to restore their previous contents. */
3416 if (proceed_to_finish)
3417 read_register_bytes (0, stop_registers, REGISTER_BYTES);
3419 if (stop_stack_dummy)
3421 /* Pop the empty frame that contains the stack dummy.
3422 POP_FRAME ends with a setting of the current frame, so we
3423 can use that next. */
3425 /* Set stop_pc to what it was before we called the function.
3426 Can't rely on restore_inferior_status because that only gets
3427 called if we don't stop in the called function. */
3428 stop_pc = read_pc ();
3429 select_frame (get_current_frame (), 0);
3433 TUIDO (((TuiOpaqueFuncPtr) tui_vCheckDataValues, selected_frame));
3436 annotate_stopped ();
3440 hook_stop_stub (void *cmd)
3442 execute_user_command ((struct cmd_list_element *) cmd, 0);
3447 signal_stop_state (int signo)
3449 return signal_stop[signo];
3453 signal_print_state (int signo)
3455 return signal_print[signo];
3459 signal_pass_state (int signo)
3461 return signal_program[signo];
3464 int signal_stop_update (signo, state)
3468 int ret = signal_stop[signo];
3469 signal_stop[signo] = state;
3473 int signal_print_update (signo, state)
3477 int ret = signal_print[signo];
3478 signal_print[signo] = state;
3482 int signal_pass_update (signo, state)
3486 int ret = signal_program[signo];
3487 signal_program[signo] = state;
3492 sig_print_header (void)
3495 Signal Stop\tPrint\tPass to program\tDescription\n");
3499 sig_print_info (enum target_signal oursig)
3501 char *name = target_signal_to_name (oursig);
3502 int name_padding = 13 - strlen (name);
3504 if (name_padding <= 0)
3507 printf_filtered ("%s", name);
3508 printf_filtered ("%*.*s ", name_padding, name_padding,
3510 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
3511 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
3512 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
3513 printf_filtered ("%s\n", target_signal_to_string (oursig));
3516 /* Specify how various signals in the inferior should be handled. */
3519 handle_command (char *args, int from_tty)
3522 int digits, wordlen;
3523 int sigfirst, signum, siglast;
3524 enum target_signal oursig;
3527 unsigned char *sigs;
3528 struct cleanup *old_chain;
3532 error_no_arg ("signal to handle");
3535 /* Allocate and zero an array of flags for which signals to handle. */
3537 nsigs = (int) TARGET_SIGNAL_LAST;
3538 sigs = (unsigned char *) alloca (nsigs);
3539 memset (sigs, 0, nsigs);
3541 /* Break the command line up into args. */
3543 argv = buildargv (args);
3548 old_chain = make_cleanup_freeargv (argv);
3550 /* Walk through the args, looking for signal oursigs, signal names, and
3551 actions. Signal numbers and signal names may be interspersed with
3552 actions, with the actions being performed for all signals cumulatively
3553 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
3555 while (*argv != NULL)
3557 wordlen = strlen (*argv);
3558 for (digits = 0; isdigit ((*argv)[digits]); digits++)
3562 sigfirst = siglast = -1;
3564 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
3566 /* Apply action to all signals except those used by the
3567 debugger. Silently skip those. */
3570 siglast = nsigs - 1;
3572 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
3574 SET_SIGS (nsigs, sigs, signal_stop);
3575 SET_SIGS (nsigs, sigs, signal_print);
3577 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
3579 UNSET_SIGS (nsigs, sigs, signal_program);
3581 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
3583 SET_SIGS (nsigs, sigs, signal_print);
3585 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
3587 SET_SIGS (nsigs, sigs, signal_program);
3589 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
3591 UNSET_SIGS (nsigs, sigs, signal_stop);
3593 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
3595 SET_SIGS (nsigs, sigs, signal_program);
3597 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
3599 UNSET_SIGS (nsigs, sigs, signal_print);
3600 UNSET_SIGS (nsigs, sigs, signal_stop);
3602 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
3604 UNSET_SIGS (nsigs, sigs, signal_program);
3606 else if (digits > 0)
3608 /* It is numeric. The numeric signal refers to our own
3609 internal signal numbering from target.h, not to host/target
3610 signal number. This is a feature; users really should be
3611 using symbolic names anyway, and the common ones like
3612 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
3614 sigfirst = siglast = (int)
3615 target_signal_from_command (atoi (*argv));
3616 if ((*argv)[digits] == '-')
3619 target_signal_from_command (atoi ((*argv) + digits + 1));
3621 if (sigfirst > siglast)
3623 /* Bet he didn't figure we'd think of this case... */
3631 oursig = target_signal_from_name (*argv);
3632 if (oursig != TARGET_SIGNAL_UNKNOWN)
3634 sigfirst = siglast = (int) oursig;
3638 /* Not a number and not a recognized flag word => complain. */
3639 error ("Unrecognized or ambiguous flag word: \"%s\".", *argv);
3643 /* If any signal numbers or symbol names were found, set flags for
3644 which signals to apply actions to. */
3646 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
3648 switch ((enum target_signal) signum)
3650 case TARGET_SIGNAL_TRAP:
3651 case TARGET_SIGNAL_INT:
3652 if (!allsigs && !sigs[signum])
3654 if (query ("%s is used by the debugger.\n\
3655 Are you sure you want to change it? ",
3656 target_signal_to_name
3657 ((enum target_signal) signum)))
3663 printf_unfiltered ("Not confirmed, unchanged.\n");
3664 gdb_flush (gdb_stdout);
3668 case TARGET_SIGNAL_0:
3669 case TARGET_SIGNAL_DEFAULT:
3670 case TARGET_SIGNAL_UNKNOWN:
3671 /* Make sure that "all" doesn't print these. */
3682 target_notice_signals (inferior_pid);
3686 /* Show the results. */
3687 sig_print_header ();
3688 for (signum = 0; signum < nsigs; signum++)
3692 sig_print_info (signum);
3697 do_cleanups (old_chain);
3701 xdb_handle_command (char *args, int from_tty)
3704 struct cleanup *old_chain;
3706 /* Break the command line up into args. */
3708 argv = buildargv (args);
3713 old_chain = make_cleanup_freeargv (argv);
3714 if (argv[1] != (char *) NULL)
3719 bufLen = strlen (argv[0]) + 20;
3720 argBuf = (char *) xmalloc (bufLen);
3724 enum target_signal oursig;
3726 oursig = target_signal_from_name (argv[0]);
3727 memset (argBuf, 0, bufLen);
3728 if (strcmp (argv[1], "Q") == 0)
3729 sprintf (argBuf, "%s %s", argv[0], "noprint");
3732 if (strcmp (argv[1], "s") == 0)
3734 if (!signal_stop[oursig])
3735 sprintf (argBuf, "%s %s", argv[0], "stop");
3737 sprintf (argBuf, "%s %s", argv[0], "nostop");
3739 else if (strcmp (argv[1], "i") == 0)
3741 if (!signal_program[oursig])
3742 sprintf (argBuf, "%s %s", argv[0], "pass");
3744 sprintf (argBuf, "%s %s", argv[0], "nopass");
3746 else if (strcmp (argv[1], "r") == 0)
3748 if (!signal_print[oursig])
3749 sprintf (argBuf, "%s %s", argv[0], "print");
3751 sprintf (argBuf, "%s %s", argv[0], "noprint");
3757 handle_command (argBuf, from_tty);
3759 printf_filtered ("Invalid signal handling flag.\n");
3764 do_cleanups (old_chain);
3767 /* Print current contents of the tables set by the handle command.
3768 It is possible we should just be printing signals actually used
3769 by the current target (but for things to work right when switching
3770 targets, all signals should be in the signal tables). */
3773 signals_info (char *signum_exp, int from_tty)
3775 enum target_signal oursig;
3776 sig_print_header ();
3780 /* First see if this is a symbol name. */
3781 oursig = target_signal_from_name (signum_exp);
3782 if (oursig == TARGET_SIGNAL_UNKNOWN)
3784 /* No, try numeric. */
3786 target_signal_from_command (parse_and_eval_address (signum_exp));
3788 sig_print_info (oursig);
3792 printf_filtered ("\n");
3793 /* These ugly casts brought to you by the native VAX compiler. */
3794 for (oursig = TARGET_SIGNAL_FIRST;
3795 (int) oursig < (int) TARGET_SIGNAL_LAST;
3796 oursig = (enum target_signal) ((int) oursig + 1))
3800 if (oursig != TARGET_SIGNAL_UNKNOWN
3801 && oursig != TARGET_SIGNAL_DEFAULT
3802 && oursig != TARGET_SIGNAL_0)
3803 sig_print_info (oursig);
3806 printf_filtered ("\nUse the \"handle\" command to change these tables.\n");
3809 struct inferior_status
3811 enum target_signal stop_signal;
3815 int stop_stack_dummy;
3816 int stopped_by_random_signal;
3818 CORE_ADDR step_range_start;
3819 CORE_ADDR step_range_end;
3820 CORE_ADDR step_frame_address;
3821 int step_over_calls;
3822 CORE_ADDR step_resume_break_address;
3823 int stop_after_trap;
3824 int stop_soon_quietly;
3825 CORE_ADDR selected_frame_address;
3826 char *stop_registers;
3828 /* These are here because if call_function_by_hand has written some
3829 registers and then decides to call error(), we better not have changed
3834 int breakpoint_proceeded;
3835 int restore_stack_info;
3836 int proceed_to_finish;
3839 static struct inferior_status *
3840 xmalloc_inferior_status (void)
3842 struct inferior_status *inf_status;
3843 inf_status = xmalloc (sizeof (struct inferior_status));
3844 inf_status->stop_registers = xmalloc (REGISTER_BYTES);
3845 inf_status->registers = xmalloc (REGISTER_BYTES);
3850 free_inferior_status (struct inferior_status *inf_status)
3852 free (inf_status->registers);
3853 free (inf_status->stop_registers);
3858 write_inferior_status_register (struct inferior_status *inf_status, int regno,
3861 int size = REGISTER_RAW_SIZE (regno);
3862 void *buf = alloca (size);
3863 store_signed_integer (buf, size, val);
3864 memcpy (&inf_status->registers[REGISTER_BYTE (regno)], buf, size);
3867 /* Save all of the information associated with the inferior<==>gdb
3868 connection. INF_STATUS is a pointer to a "struct inferior_status"
3869 (defined in inferior.h). */
3871 struct inferior_status *
3872 save_inferior_status (int restore_stack_info)
3874 struct inferior_status *inf_status = xmalloc_inferior_status ();
3876 inf_status->stop_signal = stop_signal;
3877 inf_status->stop_pc = stop_pc;
3878 inf_status->stop_step = stop_step;
3879 inf_status->stop_stack_dummy = stop_stack_dummy;
3880 inf_status->stopped_by_random_signal = stopped_by_random_signal;
3881 inf_status->trap_expected = trap_expected;
3882 inf_status->step_range_start = step_range_start;
3883 inf_status->step_range_end = step_range_end;
3884 inf_status->step_frame_address = step_frame_address;
3885 inf_status->step_over_calls = step_over_calls;
3886 inf_status->stop_after_trap = stop_after_trap;
3887 inf_status->stop_soon_quietly = stop_soon_quietly;
3888 /* Save original bpstat chain here; replace it with copy of chain.
3889 If caller's caller is walking the chain, they'll be happier if we
3890 hand them back the original chain when restore_inferior_status is
3892 inf_status->stop_bpstat = stop_bpstat;
3893 stop_bpstat = bpstat_copy (stop_bpstat);
3894 inf_status->breakpoint_proceeded = breakpoint_proceeded;
3895 inf_status->restore_stack_info = restore_stack_info;
3896 inf_status->proceed_to_finish = proceed_to_finish;
3898 memcpy (inf_status->stop_registers, stop_registers, REGISTER_BYTES);
3900 read_register_bytes (0, inf_status->registers, REGISTER_BYTES);
3902 record_selected_frame (&(inf_status->selected_frame_address),
3903 &(inf_status->selected_level));
3907 struct restore_selected_frame_args
3909 CORE_ADDR frame_address;
3914 restore_selected_frame (void *args)
3916 struct restore_selected_frame_args *fr =
3917 (struct restore_selected_frame_args *) args;
3918 struct frame_info *frame;
3919 int level = fr->level;
3921 frame = find_relative_frame (get_current_frame (), &level);
3923 /* If inf_status->selected_frame_address is NULL, there was no
3924 previously selected frame. */
3925 if (frame == NULL ||
3926 /* FRAME_FP (frame) != fr->frame_address || */
3927 /* elz: deleted this check as a quick fix to the problem that
3928 for function called by hand gdb creates no internal frame
3929 structure and the real stack and gdb's idea of stack are
3930 different if nested calls by hands are made.
3932 mvs: this worries me. */
3935 warning ("Unable to restore previously selected frame.\n");
3939 select_frame (frame, fr->level);
3945 restore_inferior_status (struct inferior_status *inf_status)
3947 stop_signal = inf_status->stop_signal;
3948 stop_pc = inf_status->stop_pc;
3949 stop_step = inf_status->stop_step;
3950 stop_stack_dummy = inf_status->stop_stack_dummy;
3951 stopped_by_random_signal = inf_status->stopped_by_random_signal;
3952 trap_expected = inf_status->trap_expected;
3953 step_range_start = inf_status->step_range_start;
3954 step_range_end = inf_status->step_range_end;
3955 step_frame_address = inf_status->step_frame_address;
3956 step_over_calls = inf_status->step_over_calls;
3957 stop_after_trap = inf_status->stop_after_trap;
3958 stop_soon_quietly = inf_status->stop_soon_quietly;
3959 bpstat_clear (&stop_bpstat);
3960 stop_bpstat = inf_status->stop_bpstat;
3961 breakpoint_proceeded = inf_status->breakpoint_proceeded;
3962 proceed_to_finish = inf_status->proceed_to_finish;
3964 /* FIXME: Is the restore of stop_registers always needed */
3965 memcpy (stop_registers, inf_status->stop_registers, REGISTER_BYTES);
3967 /* The inferior can be gone if the user types "print exit(0)"
3968 (and perhaps other times). */
3969 if (target_has_execution)
3970 write_register_bytes (0, inf_status->registers, REGISTER_BYTES);
3972 /* FIXME: If we are being called after stopping in a function which
3973 is called from gdb, we should not be trying to restore the
3974 selected frame; it just prints a spurious error message (The
3975 message is useful, however, in detecting bugs in gdb (like if gdb
3976 clobbers the stack)). In fact, should we be restoring the
3977 inferior status at all in that case? . */
3979 if (target_has_stack && inf_status->restore_stack_info)
3981 struct restore_selected_frame_args fr;
3982 fr.level = inf_status->selected_level;
3983 fr.frame_address = inf_status->selected_frame_address;
3984 /* The point of catch_errors is that if the stack is clobbered,
3985 walking the stack might encounter a garbage pointer and error()
3986 trying to dereference it. */
3987 if (catch_errors (restore_selected_frame, &fr,
3988 "Unable to restore previously selected frame:\n",
3989 RETURN_MASK_ERROR) == 0)
3990 /* Error in restoring the selected frame. Select the innermost
3994 select_frame (get_current_frame (), 0);
3998 free_inferior_status (inf_status);
4002 discard_inferior_status (struct inferior_status *inf_status)
4004 /* See save_inferior_status for info on stop_bpstat. */
4005 bpstat_clear (&inf_status->stop_bpstat);
4006 free_inferior_status (inf_status);
4010 set_follow_fork_mode_command (char *arg, int from_tty,
4011 struct cmd_list_element *c)
4013 if (!STREQ (arg, "parent") &&
4014 !STREQ (arg, "child") &&
4015 !STREQ (arg, "both") &&
4016 !STREQ (arg, "ask"))
4017 error ("follow-fork-mode must be one of \"parent\", \"child\", \"both\" or \"ask\".");
4019 if (follow_fork_mode_string != NULL)
4020 free (follow_fork_mode_string);
4021 follow_fork_mode_string = savestring (arg, strlen (arg));
4027 stop_registers = xmalloc (REGISTER_BYTES);
4031 _initialize_infrun (void)
4034 register int numsigs;
4035 struct cmd_list_element *c;
4039 register_gdbarch_swap (&stop_registers, sizeof (stop_registers), NULL);
4040 register_gdbarch_swap (NULL, 0, build_infrun);
4042 add_info ("signals", signals_info,
4043 "What debugger does when program gets various signals.\n\
4044 Specify a signal as argument to print info on that signal only.");
4045 add_info_alias ("handle", "signals", 0);
4047 add_com ("handle", class_run, handle_command,
4048 concat ("Specify how to handle a signal.\n\
4049 Args are signals and actions to apply to those signals.\n\
4050 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4051 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4052 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4053 The special arg \"all\" is recognized to mean all signals except those\n\
4054 used by the debugger, typically SIGTRAP and SIGINT.\n",
4055 "Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4056 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4057 Stop means reenter debugger if this signal happens (implies print).\n\
4058 Print means print a message if this signal happens.\n\
4059 Pass means let program see this signal; otherwise program doesn't know.\n\
4060 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4061 Pass and Stop may be combined.", NULL));
4064 add_com ("lz", class_info, signals_info,
4065 "What debugger does when program gets various signals.\n\
4066 Specify a signal as argument to print info on that signal only.");
4067 add_com ("z", class_run, xdb_handle_command,
4068 concat ("Specify how to handle a signal.\n\
4069 Args are signals and actions to apply to those signals.\n\
4070 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4071 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4072 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4073 The special arg \"all\" is recognized to mean all signals except those\n\
4074 used by the debugger, typically SIGTRAP and SIGINT.\n",
4075 "Recognized actions include \"s\" (toggles between stop and nostop), \n\
4076 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4077 nopass), \"Q\" (noprint)\n\
4078 Stop means reenter debugger if this signal happens (implies print).\n\
4079 Print means print a message if this signal happens.\n\
4080 Pass means let program see this signal; otherwise program doesn't know.\n\
4081 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4082 Pass and Stop may be combined.", NULL));
4086 stop_command = add_cmd ("stop", class_obscure, not_just_help_class_command,
4087 "There is no `stop' command, but you can set a hook on `stop'.\n\
4088 This allows you to set a list of commands to be run each time execution\n\
4089 of the program stops.", &cmdlist);
4091 numsigs = (int) TARGET_SIGNAL_LAST;
4092 signal_stop = (unsigned char *)
4093 xmalloc (sizeof (signal_stop[0]) * numsigs);
4094 signal_print = (unsigned char *)
4095 xmalloc (sizeof (signal_print[0]) * numsigs);
4096 signal_program = (unsigned char *)
4097 xmalloc (sizeof (signal_program[0]) * numsigs);
4098 for (i = 0; i < numsigs; i++)
4101 signal_print[i] = 1;
4102 signal_program[i] = 1;
4105 /* Signals caused by debugger's own actions
4106 should not be given to the program afterwards. */
4107 signal_program[TARGET_SIGNAL_TRAP] = 0;
4108 signal_program[TARGET_SIGNAL_INT] = 0;
4110 /* Signals that are not errors should not normally enter the debugger. */
4111 signal_stop[TARGET_SIGNAL_ALRM] = 0;
4112 signal_print[TARGET_SIGNAL_ALRM] = 0;
4113 signal_stop[TARGET_SIGNAL_VTALRM] = 0;
4114 signal_print[TARGET_SIGNAL_VTALRM] = 0;
4115 signal_stop[TARGET_SIGNAL_PROF] = 0;
4116 signal_print[TARGET_SIGNAL_PROF] = 0;
4117 signal_stop[TARGET_SIGNAL_CHLD] = 0;
4118 signal_print[TARGET_SIGNAL_CHLD] = 0;
4119 signal_stop[TARGET_SIGNAL_IO] = 0;
4120 signal_print[TARGET_SIGNAL_IO] = 0;
4121 signal_stop[TARGET_SIGNAL_POLL] = 0;
4122 signal_print[TARGET_SIGNAL_POLL] = 0;
4123 signal_stop[TARGET_SIGNAL_URG] = 0;
4124 signal_print[TARGET_SIGNAL_URG] = 0;
4125 signal_stop[TARGET_SIGNAL_WINCH] = 0;
4126 signal_print[TARGET_SIGNAL_WINCH] = 0;
4128 /* These signals are used internally by user-level thread
4129 implementations. (See signal(5) on Solaris.) Like the above
4130 signals, a healthy program receives and handles them as part of
4131 its normal operation. */
4132 signal_stop[TARGET_SIGNAL_LWP] = 0;
4133 signal_print[TARGET_SIGNAL_LWP] = 0;
4134 signal_stop[TARGET_SIGNAL_WAITING] = 0;
4135 signal_print[TARGET_SIGNAL_WAITING] = 0;
4136 signal_stop[TARGET_SIGNAL_CANCEL] = 0;
4137 signal_print[TARGET_SIGNAL_CANCEL] = 0;
4141 (add_set_cmd ("stop-on-solib-events", class_support, var_zinteger,
4142 (char *) &stop_on_solib_events,
4143 "Set stopping for shared library events.\n\
4144 If nonzero, gdb will give control to the user when the dynamic linker\n\
4145 notifies gdb of shared library events. The most common event of interest\n\
4146 to the user would be loading/unloading of a new library.\n",
4151 c = add_set_enum_cmd ("follow-fork-mode",
4153 follow_fork_mode_kind_names,
4154 (char *) &follow_fork_mode_string,
4155 /* ??rehrauer: The "both" option is broken, by what may be a 10.20
4156 kernel problem. It's also not terribly useful without a GUI to
4157 help the user drive two debuggers. So for now, I'm disabling
4158 the "both" option. */
4159 /* "Set debugger response to a program call of fork \
4161 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4162 parent - the original process is debugged after a fork\n\
4163 child - the new process is debugged after a fork\n\
4164 both - both the parent and child are debugged after a fork\n\
4165 ask - the debugger will ask for one of the above choices\n\
4166 For \"both\", another copy of the debugger will be started to follow\n\
4167 the new child process. The original debugger will continue to follow\n\
4168 the original parent process. To distinguish their prompts, the\n\
4169 debugger copy's prompt will be changed.\n\
4170 For \"parent\" or \"child\", the unfollowed process will run free.\n\
4171 By default, the debugger will follow the parent process.",
4173 "Set debugger response to a program call of fork \
4175 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4176 parent - the original process is debugged after a fork\n\
4177 child - the new process is debugged after a fork\n\
4178 ask - the debugger will ask for one of the above choices\n\
4179 For \"parent\" or \"child\", the unfollowed process will run free.\n\
4180 By default, the debugger will follow the parent process.",
4182 /* c->function.sfunc = ; */
4183 add_show_from_set (c, &showlist);
4185 set_follow_fork_mode_command ("parent", 0, NULL);
4187 c = add_set_enum_cmd ("scheduler-locking", class_run,
4188 scheduler_enums, /* array of string names */
4189 (char *) &scheduler_mode, /* current mode */
4190 "Set mode for locking scheduler during execution.\n\
4191 off == no locking (threads may preempt at any time)\n\
4192 on == full locking (no thread except the current thread may run)\n\
4193 step == scheduler locked during every single-step operation.\n\
4194 In this mode, no other thread may run during a step command.\n\
4195 Other threads may run while stepping over a function call ('next').",
4198 c->function.sfunc = set_schedlock_func; /* traps on target vector */
4199 add_show_from_set (c, &showlist);