1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
5 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Free Software
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 59 Temple Place - Suite 330,
23 Boston, MA 02111-1307, USA. */
26 #include "gdb_string.h"
31 #include "breakpoint.h"
35 #include "cli/cli-script.h"
37 #include "gdbthread.h"
48 /* Prototypes for local functions */
50 static void signals_info (char *, int);
52 static void handle_command (char *, int);
54 static void sig_print_info (enum target_signal);
56 static void sig_print_header (void);
58 static void resume_cleanups (void *);
60 static int hook_stop_stub (void *);
62 static void delete_breakpoint_current_contents (void *);
64 static void set_follow_fork_mode_command (char *arg, int from_tty,
65 struct cmd_list_element *c);
67 static int restore_selected_frame (void *);
69 static void build_infrun (void);
71 static int follow_fork (void);
73 static void set_schedlock_func (char *args, int from_tty,
74 struct cmd_list_element *c);
76 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 /* When set, stop the 'step' command if we enter a function which has
88 no line number information. The normal behavior is that we step
89 over such function. */
90 int step_stop_if_no_debug = 0;
92 /* In asynchronous mode, but simulating synchronous execution. */
94 int sync_execution = 0;
96 /* wait_for_inferior and normal_stop use this to notify the user
97 when the inferior stopped in a different thread than it had been
100 static ptid_t previous_inferior_ptid;
102 /* This is true for configurations that may follow through execl() and
103 similar functions. At present this is only true for HP-UX native. */
105 #ifndef MAY_FOLLOW_EXEC
106 #define MAY_FOLLOW_EXEC (0)
109 static int may_follow_exec = MAY_FOLLOW_EXEC;
111 /* If the program uses ELF-style shared libraries, then calls to
112 functions in shared libraries go through stubs, which live in a
113 table called the PLT (Procedure Linkage Table). The first time the
114 function is called, the stub sends control to the dynamic linker,
115 which looks up the function's real address, patches the stub so
116 that future calls will go directly to the function, and then passes
117 control to the function.
119 If we are stepping at the source level, we don't want to see any of
120 this --- we just want to skip over the stub and the dynamic linker.
121 The simple approach is to single-step until control leaves the
124 However, on some systems (e.g., Red Hat's 5.2 distribution) the
125 dynamic linker calls functions in the shared C library, so you
126 can't tell from the PC alone whether the dynamic linker is still
127 running. In this case, we use a step-resume breakpoint to get us
128 past the dynamic linker, as if we were using "next" to step over a
131 IN_SOLIB_DYNSYM_RESOLVE_CODE says whether we're in the dynamic
132 linker code or not. Normally, this means we single-step. However,
133 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
134 address where we can place a step-resume breakpoint to get past the
135 linker's symbol resolution function.
137 IN_SOLIB_DYNSYM_RESOLVE_CODE can generally be implemented in a
138 pretty portable way, by comparing the PC against the address ranges
139 of the dynamic linker's sections.
141 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
142 it depends on internal details of the dynamic linker. It's usually
143 not too hard to figure out where to put a breakpoint, but it
144 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
145 sanity checking. If it can't figure things out, returning zero and
146 getting the (possibly confusing) stepping behavior is better than
147 signalling an error, which will obscure the change in the
150 #ifndef IN_SOLIB_DYNSYM_RESOLVE_CODE
151 #define IN_SOLIB_DYNSYM_RESOLVE_CODE(pc) 0
154 #ifndef SKIP_SOLIB_RESOLVER
155 #define SKIP_SOLIB_RESOLVER(pc) 0
158 /* This function returns TRUE if pc is the address of an instruction
159 that lies within the dynamic linker (such as the event hook, or the
162 This function must be used only when a dynamic linker event has
163 been caught, and the inferior is being stepped out of the hook, or
164 undefined results are guaranteed. */
166 #ifndef SOLIB_IN_DYNAMIC_LINKER
167 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
170 /* On MIPS16, a function that returns a floating point value may call
171 a library helper function to copy the return value to a floating point
172 register. The IGNORE_HELPER_CALL macro returns non-zero if we
173 should ignore (i.e. step over) this function call. */
174 #ifndef IGNORE_HELPER_CALL
175 #define IGNORE_HELPER_CALL(pc) 0
178 /* On some systems, the PC may be left pointing at an instruction that won't
179 actually be executed. This is usually indicated by a bit in the PSW. If
180 we find ourselves in such a state, then we step the target beyond the
181 nullified instruction before returning control to the user so as to avoid
184 #ifndef INSTRUCTION_NULLIFIED
185 #define INSTRUCTION_NULLIFIED 0
188 /* We can't step off a permanent breakpoint in the ordinary way, because we
189 can't remove it. Instead, we have to advance the PC to the next
190 instruction. This macro should expand to a pointer to a function that
191 does that, or zero if we have no such function. If we don't have a
192 definition for it, we have to report an error. */
193 #ifndef SKIP_PERMANENT_BREAKPOINT
194 #define SKIP_PERMANENT_BREAKPOINT (default_skip_permanent_breakpoint)
196 default_skip_permanent_breakpoint (void)
199 The program is stopped at a permanent breakpoint, but GDB does not know\n\
200 how to step past a permanent breakpoint on this architecture. Try using\n\
201 a command like `return' or `jump' to continue execution.");
206 /* Convert the #defines into values. This is temporary until wfi control
207 flow is completely sorted out. */
209 #ifndef HAVE_STEPPABLE_WATCHPOINT
210 #define HAVE_STEPPABLE_WATCHPOINT 0
212 #undef HAVE_STEPPABLE_WATCHPOINT
213 #define HAVE_STEPPABLE_WATCHPOINT 1
216 #ifndef CANNOT_STEP_HW_WATCHPOINTS
217 #define CANNOT_STEP_HW_WATCHPOINTS 0
219 #undef CANNOT_STEP_HW_WATCHPOINTS
220 #define CANNOT_STEP_HW_WATCHPOINTS 1
223 /* Tables of how to react to signals; the user sets them. */
225 static unsigned char *signal_stop;
226 static unsigned char *signal_print;
227 static unsigned char *signal_program;
229 #define SET_SIGS(nsigs,sigs,flags) \
231 int signum = (nsigs); \
232 while (signum-- > 0) \
233 if ((sigs)[signum]) \
234 (flags)[signum] = 1; \
237 #define UNSET_SIGS(nsigs,sigs,flags) \
239 int signum = (nsigs); \
240 while (signum-- > 0) \
241 if ((sigs)[signum]) \
242 (flags)[signum] = 0; \
245 /* Value to pass to target_resume() to cause all threads to resume */
247 #define RESUME_ALL (pid_to_ptid (-1))
249 /* Command list pointer for the "stop" placeholder. */
251 static struct cmd_list_element *stop_command;
253 /* Nonzero if breakpoints are now inserted in the inferior. */
255 static int breakpoints_inserted;
257 /* Function inferior was in as of last step command. */
259 static struct symbol *step_start_function;
261 /* Nonzero if we are expecting a trace trap and should proceed from it. */
263 static int trap_expected;
266 /* Nonzero if we want to give control to the user when we're notified
267 of shared library events by the dynamic linker. */
268 static int stop_on_solib_events;
272 /* Nonzero if the next time we try to continue the inferior, it will
273 step one instruction and generate a spurious trace trap.
274 This is used to compensate for a bug in HP-UX. */
276 static int trap_expected_after_continue;
279 /* Nonzero means expecting a trace trap
280 and should stop the inferior and return silently when it happens. */
284 /* Nonzero means expecting a trap and caller will handle it themselves.
285 It is used after attach, due to attaching to a process;
286 when running in the shell before the child program has been exec'd;
287 and when running some kinds of remote stuff (FIXME?). */
289 enum stop_kind stop_soon_quietly;
291 /* Nonzero if proceed is being used for a "finish" command or a similar
292 situation when stop_registers should be saved. */
294 int proceed_to_finish;
296 /* Save register contents here when about to pop a stack dummy frame,
297 if-and-only-if proceed_to_finish is set.
298 Thus this contains the return value from the called function (assuming
299 values are returned in a register). */
301 struct regcache *stop_registers;
303 /* Nonzero if program stopped due to error trying to insert breakpoints. */
305 static int breakpoints_failed;
307 /* Nonzero after stop if current stack frame should be printed. */
309 static int stop_print_frame;
311 static struct breakpoint *step_resume_breakpoint = NULL;
312 static struct breakpoint *through_sigtramp_breakpoint = NULL;
314 /* On some platforms (e.g., HP-UX), hardware watchpoints have bad
315 interactions with an inferior that is running a kernel function
316 (aka, a system call or "syscall"). wait_for_inferior therefore
317 may have a need to know when the inferior is in a syscall. This
318 is a count of the number of inferior threads which are known to
319 currently be running in a syscall. */
320 static int number_of_threads_in_syscalls;
322 /* This is a cached copy of the pid/waitstatus of the last event
323 returned by target_wait()/target_wait_hook(). This information is
324 returned by get_last_target_status(). */
325 static ptid_t target_last_wait_ptid;
326 static struct target_waitstatus target_last_waitstatus;
328 /* This is used to remember when a fork, vfork or exec event
329 was caught by a catchpoint, and thus the event is to be
330 followed at the next resume of the inferior, and not
334 enum target_waitkind kind;
341 char *execd_pathname;
345 static const char follow_fork_mode_ask[] = "ask";
346 static const char follow_fork_mode_child[] = "child";
347 static const char follow_fork_mode_parent[] = "parent";
349 static const char *follow_fork_mode_kind_names[] = {
350 follow_fork_mode_ask,
351 follow_fork_mode_child,
352 follow_fork_mode_parent,
356 static const char *follow_fork_mode_string = follow_fork_mode_parent;
362 const char *follow_mode = follow_fork_mode_string;
363 int follow_child = (follow_mode == follow_fork_mode_child);
365 /* Or, did the user not know, and want us to ask? */
366 if (follow_fork_mode_string == follow_fork_mode_ask)
368 internal_error (__FILE__, __LINE__,
369 "follow_inferior_fork: \"ask\" mode not implemented");
370 /* follow_mode = follow_fork_mode_...; */
373 return target_follow_fork (follow_child);
377 follow_inferior_reset_breakpoints (void)
379 /* Was there a step_resume breakpoint? (There was if the user
380 did a "next" at the fork() call.) If so, explicitly reset its
383 step_resumes are a form of bp that are made to be per-thread.
384 Since we created the step_resume bp when the parent process
385 was being debugged, and now are switching to the child process,
386 from the breakpoint package's viewpoint, that's a switch of
387 "threads". We must update the bp's notion of which thread
388 it is for, or it'll be ignored when it triggers. */
390 if (step_resume_breakpoint)
391 breakpoint_re_set_thread (step_resume_breakpoint);
393 /* Reinsert all breakpoints in the child. The user may have set
394 breakpoints after catching the fork, in which case those
395 were never set in the child, but only in the parent. This makes
396 sure the inserted breakpoints match the breakpoint list. */
398 breakpoint_re_set ();
399 insert_breakpoints ();
402 /* EXECD_PATHNAME is assumed to be non-NULL. */
405 follow_exec (int pid, char *execd_pathname)
408 struct target_ops *tgt;
410 if (!may_follow_exec)
413 /* This is an exec event that we actually wish to pay attention to.
414 Refresh our symbol table to the newly exec'd program, remove any
417 If there are breakpoints, they aren't really inserted now,
418 since the exec() transformed our inferior into a fresh set
421 We want to preserve symbolic breakpoints on the list, since
422 we have hopes that they can be reset after the new a.out's
423 symbol table is read.
425 However, any "raw" breakpoints must be removed from the list
426 (e.g., the solib bp's), since their address is probably invalid
429 And, we DON'T want to call delete_breakpoints() here, since
430 that may write the bp's "shadow contents" (the instruction
431 value that was overwritten witha TRAP instruction). Since
432 we now have a new a.out, those shadow contents aren't valid. */
433 update_breakpoints_after_exec ();
435 /* If there was one, it's gone now. We cannot truly step-to-next
436 statement through an exec(). */
437 step_resume_breakpoint = NULL;
438 step_range_start = 0;
441 /* If there was one, it's gone now. */
442 through_sigtramp_breakpoint = NULL;
444 /* What is this a.out's name? */
445 printf_unfiltered ("Executing new program: %s\n", execd_pathname);
447 /* We've followed the inferior through an exec. Therefore, the
448 inferior has essentially been killed & reborn. */
450 /* First collect the run target in effect. */
451 tgt = find_run_target ();
452 /* If we can't find one, things are in a very strange state... */
454 error ("Could find run target to save before following exec");
456 gdb_flush (gdb_stdout);
457 target_mourn_inferior ();
458 inferior_ptid = pid_to_ptid (saved_pid);
459 /* Because mourn_inferior resets inferior_ptid. */
462 /* That a.out is now the one to use. */
463 exec_file_attach (execd_pathname, 0);
465 /* And also is where symbols can be found. */
466 symbol_file_add_main (execd_pathname, 0);
468 /* Reset the shared library package. This ensures that we get
469 a shlib event when the child reaches "_start", at which point
470 the dld will have had a chance to initialize the child. */
471 #if defined(SOLIB_RESTART)
474 #ifdef SOLIB_CREATE_INFERIOR_HOOK
475 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
478 /* Reinsert all breakpoints. (Those which were symbolic have
479 been reset to the proper address in the new a.out, thanks
480 to symbol_file_command...) */
481 insert_breakpoints ();
483 /* The next resume of this inferior should bring it to the shlib
484 startup breakpoints. (If the user had also set bp's on
485 "main" from the old (parent) process, then they'll auto-
486 matically get reset there in the new process.) */
489 /* Non-zero if we just simulating a single-step. This is needed
490 because we cannot remove the breakpoints in the inferior process
491 until after the `wait' in `wait_for_inferior'. */
492 static int singlestep_breakpoints_inserted_p = 0;
495 /* Things to clean up if we QUIT out of resume (). */
498 resume_cleanups (void *ignore)
503 static const char schedlock_off[] = "off";
504 static const char schedlock_on[] = "on";
505 static const char schedlock_step[] = "step";
506 static const char *scheduler_mode = schedlock_off;
507 static const char *scheduler_enums[] = {
515 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
517 /* NOTE: cagney/2002-03-17: The add_show_from_set() function clones
518 the set command passed as a parameter. The clone operation will
519 include (BUG?) any ``set'' command callback, if present.
520 Commands like ``info set'' call all the ``show'' command
521 callbacks. Unfortunatly, for ``show'' commands cloned from
522 ``set'', this includes callbacks belonging to ``set'' commands.
523 Making this worse, this only occures if add_show_from_set() is
524 called after add_cmd_sfunc() (BUG?). */
525 if (cmd_type (c) == set_cmd)
526 if (!target_can_lock_scheduler)
528 scheduler_mode = schedlock_off;
529 error ("Target '%s' cannot support this command.", target_shortname);
534 /* Resume the inferior, but allow a QUIT. This is useful if the user
535 wants to interrupt some lengthy single-stepping operation
536 (for child processes, the SIGINT goes to the inferior, and so
537 we get a SIGINT random_signal, but for remote debugging and perhaps
538 other targets, that's not true).
540 STEP nonzero if we should step (zero to continue instead).
541 SIG is the signal to give the inferior (zero for none). */
543 resume (int step, enum target_signal sig)
545 int should_resume = 1;
546 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
549 /* FIXME: calling breakpoint_here_p (read_pc ()) three times! */
552 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
553 over an instruction that causes a page fault without triggering
554 a hardware watchpoint. The kernel properly notices that it shouldn't
555 stop, because the hardware watchpoint is not triggered, but it forgets
556 the step request and continues the program normally.
557 Work around the problem by removing hardware watchpoints if a step is
558 requested, GDB will check for a hardware watchpoint trigger after the
560 if (CANNOT_STEP_HW_WATCHPOINTS && step && breakpoints_inserted)
561 remove_hw_watchpoints ();
564 /* Normally, by the time we reach `resume', the breakpoints are either
565 removed or inserted, as appropriate. The exception is if we're sitting
566 at a permanent breakpoint; we need to step over it, but permanent
567 breakpoints can't be removed. So we have to test for it here. */
568 if (breakpoint_here_p (read_pc ()) == permanent_breakpoint_here)
569 SKIP_PERMANENT_BREAKPOINT ();
571 if (SOFTWARE_SINGLE_STEP_P () && step)
573 /* Do it the hard way, w/temp breakpoints */
574 SOFTWARE_SINGLE_STEP (sig, 1 /*insert-breakpoints */ );
575 /* ...and don't ask hardware to do it. */
577 /* and do not pull these breakpoints until after a `wait' in
578 `wait_for_inferior' */
579 singlestep_breakpoints_inserted_p = 1;
582 /* Handle any optimized stores to the inferior NOW... */
583 #ifdef DO_DEFERRED_STORES
587 /* If there were any forks/vforks/execs that were caught and are
588 now to be followed, then do so. */
589 switch (pending_follow.kind)
591 case TARGET_WAITKIND_FORKED:
592 case TARGET_WAITKIND_VFORKED:
593 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
598 case TARGET_WAITKIND_EXECD:
599 /* follow_exec is called as soon as the exec event is seen. */
600 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
607 /* Install inferior's terminal modes. */
608 target_terminal_inferior ();
614 resume_ptid = RESUME_ALL; /* Default */
616 if ((step || singlestep_breakpoints_inserted_p) &&
617 !breakpoints_inserted && breakpoint_here_p (read_pc ()))
619 /* Stepping past a breakpoint without inserting breakpoints.
620 Make sure only the current thread gets to step, so that
621 other threads don't sneak past breakpoints while they are
624 resume_ptid = inferior_ptid;
627 if ((scheduler_mode == schedlock_on) ||
628 (scheduler_mode == schedlock_step &&
629 (step || singlestep_breakpoints_inserted_p)))
631 /* User-settable 'scheduler' mode requires solo thread resume. */
632 resume_ptid = inferior_ptid;
635 if (CANNOT_STEP_BREAKPOINT)
637 /* Most targets can step a breakpoint instruction, thus
638 executing it normally. But if this one cannot, just
639 continue and we will hit it anyway. */
640 if (step && breakpoints_inserted && breakpoint_here_p (read_pc ()))
643 target_resume (resume_ptid, step, sig);
646 discard_cleanups (old_cleanups);
650 /* Clear out all variables saying what to do when inferior is continued.
651 First do this, then set the ones you want, then call `proceed'. */
654 clear_proceed_status (void)
657 step_range_start = 0;
659 step_frame_id = null_frame_id;
660 step_over_calls = STEP_OVER_UNDEBUGGABLE;
662 stop_soon_quietly = NO_STOP_QUIETLY;
663 proceed_to_finish = 0;
664 breakpoint_proceeded = 1; /* We're about to proceed... */
666 /* Discard any remaining commands or status from previous stop. */
667 bpstat_clear (&stop_bpstat);
670 /* Basic routine for continuing the program in various fashions.
672 ADDR is the address to resume at, or -1 for resume where stopped.
673 SIGGNAL is the signal to give it, or 0 for none,
674 or -1 for act according to how it stopped.
675 STEP is nonzero if should trap after one instruction.
676 -1 means return after that and print nothing.
677 You should probably set various step_... variables
678 before calling here, if you are stepping.
680 You should call clear_proceed_status before calling proceed. */
683 proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
688 step_start_function = find_pc_function (read_pc ());
692 if (addr == (CORE_ADDR) -1)
694 /* If there is a breakpoint at the address we will resume at,
695 step one instruction before inserting breakpoints
696 so that we do not stop right away (and report a second
697 hit at this breakpoint). */
699 if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
702 #ifndef STEP_SKIPS_DELAY
703 #define STEP_SKIPS_DELAY(pc) (0)
704 #define STEP_SKIPS_DELAY_P (0)
706 /* Check breakpoint_here_p first, because breakpoint_here_p is fast
707 (it just checks internal GDB data structures) and STEP_SKIPS_DELAY
708 is slow (it needs to read memory from the target). */
709 if (STEP_SKIPS_DELAY_P
710 && breakpoint_here_p (read_pc () + 4)
711 && STEP_SKIPS_DELAY (read_pc ()))
719 #ifdef PREPARE_TO_PROCEED
720 /* In a multi-threaded task we may select another thread
721 and then continue or step.
723 But if the old thread was stopped at a breakpoint, it
724 will immediately cause another breakpoint stop without
725 any execution (i.e. it will report a breakpoint hit
726 incorrectly). So we must step over it first.
728 PREPARE_TO_PROCEED checks the current thread against the thread
729 that reported the most recent event. If a step-over is required
730 it returns TRUE and sets the current thread to the old thread. */
731 if (PREPARE_TO_PROCEED (1) && breakpoint_here_p (read_pc ()))
736 #endif /* PREPARE_TO_PROCEED */
739 if (trap_expected_after_continue)
741 /* If (step == 0), a trap will be automatically generated after
742 the first instruction is executed. Force step one
743 instruction to clear this condition. This should not occur
744 if step is nonzero, but it is harmless in that case. */
746 trap_expected_after_continue = 0;
748 #endif /* HP_OS_BUG */
751 /* We will get a trace trap after one instruction.
752 Continue it automatically and insert breakpoints then. */
756 insert_breakpoints ();
757 /* If we get here there was no call to error() in
758 insert breakpoints -- so they were inserted. */
759 breakpoints_inserted = 1;
762 if (siggnal != TARGET_SIGNAL_DEFAULT)
763 stop_signal = siggnal;
764 /* If this signal should not be seen by program,
765 give it zero. Used for debugging signals. */
766 else if (!signal_program[stop_signal])
767 stop_signal = TARGET_SIGNAL_0;
769 annotate_starting ();
771 /* Make sure that output from GDB appears before output from the
773 gdb_flush (gdb_stdout);
775 /* Resume inferior. */
776 resume (oneproc || step || bpstat_should_step (), stop_signal);
778 /* Wait for it to stop (if not standalone)
779 and in any case decode why it stopped, and act accordingly. */
780 /* Do this only if we are not using the event loop, or if the target
781 does not support asynchronous execution. */
782 if (!event_loop_p || !target_can_async_p ())
784 wait_for_inferior ();
789 /* Record the pc and sp of the program the last time it stopped.
790 These are just used internally by wait_for_inferior, but need
791 to be preserved over calls to it and cleared when the inferior
793 static CORE_ADDR prev_pc;
794 static CORE_ADDR prev_func_start;
795 static char *prev_func_name;
798 /* Start remote-debugging of a machine over a serial link. */
804 init_wait_for_inferior ();
805 stop_soon_quietly = STOP_QUIETLY;
808 /* Always go on waiting for the target, regardless of the mode. */
809 /* FIXME: cagney/1999-09-23: At present it isn't possible to
810 indicate to wait_for_inferior that a target should timeout if
811 nothing is returned (instead of just blocking). Because of this,
812 targets expecting an immediate response need to, internally, set
813 things up so that the target_wait() is forced to eventually
815 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
816 differentiate to its caller what the state of the target is after
817 the initial open has been performed. Here we're assuming that
818 the target has stopped. It should be possible to eventually have
819 target_open() return to the caller an indication that the target
820 is currently running and GDB state should be set to the same as
822 wait_for_inferior ();
826 /* Initialize static vars when a new inferior begins. */
829 init_wait_for_inferior (void)
831 /* These are meaningless until the first time through wait_for_inferior. */
834 prev_func_name = NULL;
837 trap_expected_after_continue = 0;
839 breakpoints_inserted = 0;
840 breakpoint_init_inferior (inf_starting);
842 /* Don't confuse first call to proceed(). */
843 stop_signal = TARGET_SIGNAL_0;
845 /* The first resume is not following a fork/vfork/exec. */
846 pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
848 /* See wait_for_inferior's handling of SYSCALL_ENTRY/RETURN events. */
849 number_of_threads_in_syscalls = 0;
851 clear_proceed_status ();
855 delete_breakpoint_current_contents (void *arg)
857 struct breakpoint **breakpointp = (struct breakpoint **) arg;
858 if (*breakpointp != NULL)
860 delete_breakpoint (*breakpointp);
865 /* This enum encodes possible reasons for doing a target_wait, so that
866 wfi can call target_wait in one place. (Ultimately the call will be
867 moved out of the infinite loop entirely.) */
871 infwait_normal_state,
872 infwait_thread_hop_state,
873 infwait_nullified_state,
874 infwait_nonstep_watch_state
877 /* Why did the inferior stop? Used to print the appropriate messages
878 to the interface from within handle_inferior_event(). */
879 enum inferior_stop_reason
881 /* We don't know why. */
883 /* Step, next, nexti, stepi finished. */
885 /* Found breakpoint. */
887 /* Inferior terminated by signal. */
889 /* Inferior exited. */
891 /* Inferior received signal, and user asked to be notified. */
895 /* This structure contains what used to be local variables in
896 wait_for_inferior. Probably many of them can return to being
897 locals in handle_inferior_event. */
899 struct execution_control_state
901 struct target_waitstatus ws;
902 struct target_waitstatus *wp;
905 CORE_ADDR stop_func_start;
906 CORE_ADDR stop_func_end;
907 char *stop_func_name;
908 struct symtab_and_line sal;
909 int remove_breakpoints_on_following_step;
911 struct symtab *current_symtab;
912 int handling_longjmp; /* FIXME */
914 ptid_t saved_inferior_ptid;
916 int stepping_through_solib_after_catch;
917 bpstat stepping_through_solib_catchpoints;
918 int enable_hw_watchpoints_after_wait;
919 int stepping_through_sigtramp;
920 int new_thread_event;
921 struct target_waitstatus tmpstatus;
922 enum infwait_states infwait_state;
927 void init_execution_control_state (struct execution_control_state *ecs);
929 void handle_inferior_event (struct execution_control_state *ecs);
931 static void check_sigtramp2 (struct execution_control_state *ecs);
932 static void step_into_function (struct execution_control_state *ecs);
933 static void step_over_function (struct execution_control_state *ecs);
934 static void stop_stepping (struct execution_control_state *ecs);
935 static void prepare_to_wait (struct execution_control_state *ecs);
936 static void keep_going (struct execution_control_state *ecs);
937 static void print_stop_reason (enum inferior_stop_reason stop_reason,
940 /* Wait for control to return from inferior to debugger.
941 If inferior gets a signal, we may decide to start it up again
942 instead of returning. That is why there is a loop in this function.
943 When this function actually returns it means the inferior
944 should be left stopped and GDB should read more commands. */
947 wait_for_inferior (void)
949 struct cleanup *old_cleanups;
950 struct execution_control_state ecss;
951 struct execution_control_state *ecs;
953 old_cleanups = make_cleanup (delete_step_resume_breakpoint,
954 &step_resume_breakpoint);
955 make_cleanup (delete_breakpoint_current_contents,
956 &through_sigtramp_breakpoint);
958 /* wfi still stays in a loop, so it's OK just to take the address of
959 a local to get the ecs pointer. */
962 /* Fill in with reasonable starting values. */
963 init_execution_control_state (ecs);
965 /* We'll update this if & when we switch to a new thread. */
966 previous_inferior_ptid = inferior_ptid;
968 overlay_cache_invalid = 1;
970 /* We have to invalidate the registers BEFORE calling target_wait
971 because they can be loaded from the target while in target_wait.
972 This makes remote debugging a bit more efficient for those
973 targets that provide critical registers as part of their normal
976 registers_changed ();
980 if (target_wait_hook)
981 ecs->ptid = target_wait_hook (ecs->waiton_ptid, ecs->wp);
983 ecs->ptid = target_wait (ecs->waiton_ptid, ecs->wp);
985 /* Now figure out what to do with the result of the result. */
986 handle_inferior_event (ecs);
988 if (!ecs->wait_some_more)
991 do_cleanups (old_cleanups);
994 /* Asynchronous version of wait_for_inferior. It is called by the
995 event loop whenever a change of state is detected on the file
996 descriptor corresponding to the target. It can be called more than
997 once to complete a single execution command. In such cases we need
998 to keep the state in a global variable ASYNC_ECSS. If it is the
999 last time that this function is called for a single execution
1000 command, then report to the user that the inferior has stopped, and
1001 do the necessary cleanups. */
1003 struct execution_control_state async_ecss;
1004 struct execution_control_state *async_ecs;
1007 fetch_inferior_event (void *client_data)
1009 static struct cleanup *old_cleanups;
1011 async_ecs = &async_ecss;
1013 if (!async_ecs->wait_some_more)
1015 old_cleanups = make_exec_cleanup (delete_step_resume_breakpoint,
1016 &step_resume_breakpoint);
1017 make_exec_cleanup (delete_breakpoint_current_contents,
1018 &through_sigtramp_breakpoint);
1020 /* Fill in with reasonable starting values. */
1021 init_execution_control_state (async_ecs);
1023 /* We'll update this if & when we switch to a new thread. */
1024 previous_inferior_ptid = inferior_ptid;
1026 overlay_cache_invalid = 1;
1028 /* We have to invalidate the registers BEFORE calling target_wait
1029 because they can be loaded from the target while in target_wait.
1030 This makes remote debugging a bit more efficient for those
1031 targets that provide critical registers as part of their normal
1032 status mechanism. */
1034 registers_changed ();
1037 if (target_wait_hook)
1039 target_wait_hook (async_ecs->waiton_ptid, async_ecs->wp);
1041 async_ecs->ptid = target_wait (async_ecs->waiton_ptid, async_ecs->wp);
1043 /* Now figure out what to do with the result of the result. */
1044 handle_inferior_event (async_ecs);
1046 if (!async_ecs->wait_some_more)
1048 /* Do only the cleanups that have been added by this
1049 function. Let the continuations for the commands do the rest,
1050 if there are any. */
1051 do_exec_cleanups (old_cleanups);
1053 if (step_multi && stop_step)
1054 inferior_event_handler (INF_EXEC_CONTINUE, NULL);
1056 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
1060 /* Prepare an execution control state for looping through a
1061 wait_for_inferior-type loop. */
1064 init_execution_control_state (struct execution_control_state *ecs)
1066 /* ecs->another_trap? */
1067 ecs->random_signal = 0;
1068 ecs->remove_breakpoints_on_following_step = 0;
1069 ecs->handling_longjmp = 0; /* FIXME */
1070 ecs->update_step_sp = 0;
1071 ecs->stepping_through_solib_after_catch = 0;
1072 ecs->stepping_through_solib_catchpoints = NULL;
1073 ecs->enable_hw_watchpoints_after_wait = 0;
1074 ecs->stepping_through_sigtramp = 0;
1075 ecs->sal = find_pc_line (prev_pc, 0);
1076 ecs->current_line = ecs->sal.line;
1077 ecs->current_symtab = ecs->sal.symtab;
1078 ecs->infwait_state = infwait_normal_state;
1079 ecs->waiton_ptid = pid_to_ptid (-1);
1080 ecs->wp = &(ecs->ws);
1083 /* Call this function before setting step_resume_breakpoint, as a
1084 sanity check. There should never be more than one step-resume
1085 breakpoint per thread, so we should never be setting a new
1086 step_resume_breakpoint when one is already active. */
1088 check_for_old_step_resume_breakpoint (void)
1090 if (step_resume_breakpoint)
1092 ("GDB bug: infrun.c (wait_for_inferior): dropping old step_resume breakpoint");
1095 /* Return the cached copy of the last pid/waitstatus returned by
1096 target_wait()/target_wait_hook(). The data is actually cached by
1097 handle_inferior_event(), which gets called immediately after
1098 target_wait()/target_wait_hook(). */
1101 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
1103 *ptidp = target_last_wait_ptid;
1104 *status = target_last_waitstatus;
1107 /* Switch thread contexts, maintaining "infrun state". */
1110 context_switch (struct execution_control_state *ecs)
1112 /* Caution: it may happen that the new thread (or the old one!)
1113 is not in the thread list. In this case we must not attempt
1114 to "switch context", or we run the risk that our context may
1115 be lost. This may happen as a result of the target module
1116 mishandling thread creation. */
1118 if (in_thread_list (inferior_ptid) && in_thread_list (ecs->ptid))
1119 { /* Perform infrun state context switch: */
1120 /* Save infrun state for the old thread. */
1121 save_infrun_state (inferior_ptid, prev_pc,
1122 prev_func_start, prev_func_name,
1123 trap_expected, step_resume_breakpoint,
1124 through_sigtramp_breakpoint, step_range_start,
1125 step_range_end, &step_frame_id,
1126 ecs->handling_longjmp, ecs->another_trap,
1127 ecs->stepping_through_solib_after_catch,
1128 ecs->stepping_through_solib_catchpoints,
1129 ecs->stepping_through_sigtramp,
1130 ecs->current_line, ecs->current_symtab, step_sp);
1132 /* Load infrun state for the new thread. */
1133 load_infrun_state (ecs->ptid, &prev_pc,
1134 &prev_func_start, &prev_func_name,
1135 &trap_expected, &step_resume_breakpoint,
1136 &through_sigtramp_breakpoint, &step_range_start,
1137 &step_range_end, &step_frame_id,
1138 &ecs->handling_longjmp, &ecs->another_trap,
1139 &ecs->stepping_through_solib_after_catch,
1140 &ecs->stepping_through_solib_catchpoints,
1141 &ecs->stepping_through_sigtramp,
1142 &ecs->current_line, &ecs->current_symtab, &step_sp);
1144 inferior_ptid = ecs->ptid;
1148 /* Given an execution control state that has been freshly filled in
1149 by an event from the inferior, figure out what it means and take
1150 appropriate action. */
1153 handle_inferior_event (struct execution_control_state *ecs)
1155 CORE_ADDR real_stop_pc;
1156 /* NOTE: cagney/2003-03-28: If you're looking at this code and
1157 thinking that the variable stepped_after_stopped_by_watchpoint
1158 isn't used, then you're wrong! The macro STOPPED_BY_WATCHPOINT,
1159 defined in the file "config/pa/nm-hppah.h", accesses the variable
1160 indirectly. Mutter something rude about the HP merge. */
1161 int stepped_after_stopped_by_watchpoint;
1162 int sw_single_step_trap_p = 0;
1164 /* Cache the last pid/waitstatus. */
1165 target_last_wait_ptid = ecs->ptid;
1166 target_last_waitstatus = *ecs->wp;
1168 switch (ecs->infwait_state)
1170 case infwait_thread_hop_state:
1171 /* Cancel the waiton_ptid. */
1172 ecs->waiton_ptid = pid_to_ptid (-1);
1173 /* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
1174 is serviced in this loop, below. */
1175 if (ecs->enable_hw_watchpoints_after_wait)
1177 TARGET_ENABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
1178 ecs->enable_hw_watchpoints_after_wait = 0;
1180 stepped_after_stopped_by_watchpoint = 0;
1183 case infwait_normal_state:
1184 /* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
1185 is serviced in this loop, below. */
1186 if (ecs->enable_hw_watchpoints_after_wait)
1188 TARGET_ENABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
1189 ecs->enable_hw_watchpoints_after_wait = 0;
1191 stepped_after_stopped_by_watchpoint = 0;
1194 case infwait_nullified_state:
1195 stepped_after_stopped_by_watchpoint = 0;
1198 case infwait_nonstep_watch_state:
1199 insert_breakpoints ();
1201 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1202 handle things like signals arriving and other things happening
1203 in combination correctly? */
1204 stepped_after_stopped_by_watchpoint = 1;
1208 internal_error (__FILE__, __LINE__, "bad switch");
1210 ecs->infwait_state = infwait_normal_state;
1212 flush_cached_frames ();
1214 /* If it's a new process, add it to the thread database */
1216 ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
1217 && !in_thread_list (ecs->ptid));
1219 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
1220 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
1222 add_thread (ecs->ptid);
1224 ui_out_text (uiout, "[New ");
1225 ui_out_text (uiout, target_pid_or_tid_to_str (ecs->ptid));
1226 ui_out_text (uiout, "]\n");
1229 /* NOTE: This block is ONLY meant to be invoked in case of a
1230 "thread creation event"! If it is invoked for any other
1231 sort of event (such as a new thread landing on a breakpoint),
1232 the event will be discarded, which is almost certainly
1235 To avoid this, the low-level module (eg. target_wait)
1236 should call in_thread_list and add_thread, so that the
1237 new thread is known by the time we get here. */
1239 /* We may want to consider not doing a resume here in order
1240 to give the user a chance to play with the new thread.
1241 It might be good to make that a user-settable option. */
1243 /* At this point, all threads are stopped (happens
1244 automatically in either the OS or the native code).
1245 Therefore we need to continue all threads in order to
1248 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
1249 prepare_to_wait (ecs);
1254 switch (ecs->ws.kind)
1256 case TARGET_WAITKIND_LOADED:
1257 /* Ignore gracefully during startup of the inferior, as it
1258 might be the shell which has just loaded some objects,
1259 otherwise add the symbols for the newly loaded objects. */
1261 if (stop_soon_quietly == NO_STOP_QUIETLY)
1263 /* Remove breakpoints, SOLIB_ADD might adjust
1264 breakpoint addresses via breakpoint_re_set. */
1265 if (breakpoints_inserted)
1266 remove_breakpoints ();
1268 /* Check for any newly added shared libraries if we're
1269 supposed to be adding them automatically. Switch
1270 terminal for any messages produced by
1271 breakpoint_re_set. */
1272 target_terminal_ours_for_output ();
1273 SOLIB_ADD (NULL, 0, NULL, auto_solib_add);
1274 target_terminal_inferior ();
1276 /* Reinsert breakpoints and continue. */
1277 if (breakpoints_inserted)
1278 insert_breakpoints ();
1281 resume (0, TARGET_SIGNAL_0);
1282 prepare_to_wait (ecs);
1285 case TARGET_WAITKIND_SPURIOUS:
1286 resume (0, TARGET_SIGNAL_0);
1287 prepare_to_wait (ecs);
1290 case TARGET_WAITKIND_EXITED:
1291 target_terminal_ours (); /* Must do this before mourn anyway */
1292 print_stop_reason (EXITED, ecs->ws.value.integer);
1294 /* Record the exit code in the convenience variable $_exitcode, so
1295 that the user can inspect this again later. */
1296 set_internalvar (lookup_internalvar ("_exitcode"),
1297 value_from_longest (builtin_type_int,
1298 (LONGEST) ecs->ws.value.integer));
1299 gdb_flush (gdb_stdout);
1300 target_mourn_inferior ();
1301 singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
1302 stop_print_frame = 0;
1303 stop_stepping (ecs);
1306 case TARGET_WAITKIND_SIGNALLED:
1307 stop_print_frame = 0;
1308 stop_signal = ecs->ws.value.sig;
1309 target_terminal_ours (); /* Must do this before mourn anyway */
1311 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
1312 reach here unless the inferior is dead. However, for years
1313 target_kill() was called here, which hints that fatal signals aren't
1314 really fatal on some systems. If that's true, then some changes
1316 target_mourn_inferior ();
1318 print_stop_reason (SIGNAL_EXITED, stop_signal);
1319 singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
1320 stop_stepping (ecs);
1323 /* The following are the only cases in which we keep going;
1324 the above cases end in a continue or goto. */
1325 case TARGET_WAITKIND_FORKED:
1326 case TARGET_WAITKIND_VFORKED:
1327 stop_signal = TARGET_SIGNAL_TRAP;
1328 pending_follow.kind = ecs->ws.kind;
1330 pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
1331 pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
1333 stop_pc = read_pc ();
1335 /* Assume that catchpoints are not really software breakpoints. If
1336 some future target implements them using software breakpoints then
1337 that target is responsible for fudging DECR_PC_AFTER_BREAK. Thus
1338 we pass 1 for the NOT_A_SW_BREAKPOINT argument, so that
1339 bpstat_stop_status will not decrement the PC. */
1341 stop_bpstat = bpstat_stop_status (&stop_pc, 1);
1343 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1345 /* If no catchpoint triggered for this, then keep going. */
1346 if (ecs->random_signal)
1348 stop_signal = TARGET_SIGNAL_0;
1352 goto process_event_stop_test;
1354 case TARGET_WAITKIND_EXECD:
1355 stop_signal = TARGET_SIGNAL_TRAP;
1357 /* NOTE drow/2002-12-05: This code should be pushed down into the
1358 target_wait function. Until then following vfork on HP/UX 10.20
1359 is probably broken by this. Of course, it's broken anyway. */
1360 /* Is this a target which reports multiple exec events per actual
1361 call to exec()? (HP-UX using ptrace does, for example.) If so,
1362 ignore all but the last one. Just resume the exec'r, and wait
1363 for the next exec event. */
1364 if (inferior_ignoring_leading_exec_events)
1366 inferior_ignoring_leading_exec_events--;
1367 if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
1368 ENSURE_VFORKING_PARENT_REMAINS_STOPPED (pending_follow.fork_event.
1370 target_resume (ecs->ptid, 0, TARGET_SIGNAL_0);
1371 prepare_to_wait (ecs);
1374 inferior_ignoring_leading_exec_events =
1375 target_reported_exec_events_per_exec_call () - 1;
1377 pending_follow.execd_pathname =
1378 savestring (ecs->ws.value.execd_pathname,
1379 strlen (ecs->ws.value.execd_pathname));
1381 /* This causes the eventpoints and symbol table to be reset. Must
1382 do this now, before trying to determine whether to stop. */
1383 follow_exec (PIDGET (inferior_ptid), pending_follow.execd_pathname);
1384 xfree (pending_follow.execd_pathname);
1386 stop_pc = read_pc_pid (ecs->ptid);
1387 ecs->saved_inferior_ptid = inferior_ptid;
1388 inferior_ptid = ecs->ptid;
1390 /* Assume that catchpoints are not really software breakpoints. If
1391 some future target implements them using software breakpoints then
1392 that target is responsible for fudging DECR_PC_AFTER_BREAK. Thus
1393 we pass 1 for the NOT_A_SW_BREAKPOINT argument, so that
1394 bpstat_stop_status will not decrement the PC. */
1396 stop_bpstat = bpstat_stop_status (&stop_pc, 1);
1398 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1399 inferior_ptid = ecs->saved_inferior_ptid;
1401 /* If no catchpoint triggered for this, then keep going. */
1402 if (ecs->random_signal)
1404 stop_signal = TARGET_SIGNAL_0;
1408 goto process_event_stop_test;
1410 /* These syscall events are returned on HP-UX, as part of its
1411 implementation of page-protection-based "hardware" watchpoints.
1412 HP-UX has unfortunate interactions between page-protections and
1413 some system calls. Our solution is to disable hardware watches
1414 when a system call is entered, and reenable them when the syscall
1415 completes. The downside of this is that we may miss the precise
1416 point at which a watched piece of memory is modified. "Oh well."
1418 Note that we may have multiple threads running, which may each
1419 enter syscalls at roughly the same time. Since we don't have a
1420 good notion currently of whether a watched piece of memory is
1421 thread-private, we'd best not have any page-protections active
1422 when any thread is in a syscall. Thus, we only want to reenable
1423 hardware watches when no threads are in a syscall.
1425 Also, be careful not to try to gather much state about a thread
1426 that's in a syscall. It's frequently a losing proposition. */
1427 case TARGET_WAITKIND_SYSCALL_ENTRY:
1428 number_of_threads_in_syscalls++;
1429 if (number_of_threads_in_syscalls == 1)
1431 TARGET_DISABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
1433 resume (0, TARGET_SIGNAL_0);
1434 prepare_to_wait (ecs);
1437 /* Before examining the threads further, step this thread to
1438 get it entirely out of the syscall. (We get notice of the
1439 event when the thread is just on the verge of exiting a
1440 syscall. Stepping one instruction seems to get it back
1443 Note that although the logical place to reenable h/w watches
1444 is here, we cannot. We cannot reenable them before stepping
1445 the thread (this causes the next wait on the thread to hang).
1447 Nor can we enable them after stepping until we've done a wait.
1448 Thus, we simply set the flag ecs->enable_hw_watchpoints_after_wait
1449 here, which will be serviced immediately after the target
1451 case TARGET_WAITKIND_SYSCALL_RETURN:
1452 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1454 if (number_of_threads_in_syscalls > 0)
1456 number_of_threads_in_syscalls--;
1457 ecs->enable_hw_watchpoints_after_wait =
1458 (number_of_threads_in_syscalls == 0);
1460 prepare_to_wait (ecs);
1463 case TARGET_WAITKIND_STOPPED:
1464 stop_signal = ecs->ws.value.sig;
1467 /* We had an event in the inferior, but we are not interested
1468 in handling it at this level. The lower layers have already
1469 done what needs to be done, if anything.
1471 One of the possible circumstances for this is when the
1472 inferior produces output for the console. The inferior has
1473 not stopped, and we are ignoring the event. Another possible
1474 circumstance is any event which the lower level knows will be
1475 reported multiple times without an intervening resume. */
1476 case TARGET_WAITKIND_IGNORE:
1477 prepare_to_wait (ecs);
1481 /* We may want to consider not doing a resume here in order to give
1482 the user a chance to play with the new thread. It might be good
1483 to make that a user-settable option. */
1485 /* At this point, all threads are stopped (happens automatically in
1486 either the OS or the native code). Therefore we need to continue
1487 all threads in order to make progress. */
1488 if (ecs->new_thread_event)
1490 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
1491 prepare_to_wait (ecs);
1495 stop_pc = read_pc_pid (ecs->ptid);
1497 /* See if a thread hit a thread-specific breakpoint that was meant for
1498 another thread. If so, then step that thread past the breakpoint,
1501 if (stop_signal == TARGET_SIGNAL_TRAP)
1503 /* Check if a regular breakpoint has been hit before checking
1504 for a potential single step breakpoint. Otherwise, GDB will
1505 not see this breakpoint hit when stepping onto breakpoints. */
1506 if (breakpoints_inserted
1507 && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK))
1509 ecs->random_signal = 0;
1510 if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK,
1515 /* Saw a breakpoint, but it was hit by the wrong thread.
1517 if (DECR_PC_AFTER_BREAK)
1518 write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, ecs->ptid);
1520 remove_status = remove_breakpoints ();
1521 /* Did we fail to remove breakpoints? If so, try
1522 to set the PC past the bp. (There's at least
1523 one situation in which we can fail to remove
1524 the bp's: On HP-UX's that use ttrace, we can't
1525 change the address space of a vforking child
1526 process until the child exits (well, okay, not
1527 then either :-) or execs. */
1528 if (remove_status != 0)
1530 /* FIXME! This is obviously non-portable! */
1531 write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK + 4, ecs->ptid);
1532 /* We need to restart all the threads now,
1533 * unles we're running in scheduler-locked mode.
1534 * Use currently_stepping to determine whether to
1537 /* FIXME MVS: is there any reason not to call resume()? */
1538 if (scheduler_mode == schedlock_on)
1539 target_resume (ecs->ptid,
1540 currently_stepping (ecs), TARGET_SIGNAL_0);
1542 target_resume (RESUME_ALL,
1543 currently_stepping (ecs), TARGET_SIGNAL_0);
1544 prepare_to_wait (ecs);
1549 breakpoints_inserted = 0;
1550 if (!ptid_equal (inferior_ptid, ecs->ptid))
1551 context_switch (ecs);
1552 ecs->waiton_ptid = ecs->ptid;
1553 ecs->wp = &(ecs->ws);
1554 ecs->another_trap = 1;
1556 ecs->infwait_state = infwait_thread_hop_state;
1558 registers_changed ();
1563 else if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
1565 /* Readjust the stop_pc as it is off by DECR_PC_AFTER_BREAK
1566 compared to the value it would have if the system stepping
1567 capability was used. This allows the rest of the code in
1568 this function to use this address without having to worry
1569 whether software single step is in use or not. */
1570 if (DECR_PC_AFTER_BREAK)
1572 stop_pc -= DECR_PC_AFTER_BREAK;
1573 write_pc_pid (stop_pc, ecs->ptid);
1576 sw_single_step_trap_p = 1;
1577 ecs->random_signal = 0;
1581 ecs->random_signal = 1;
1583 /* See if something interesting happened to the non-current thread. If
1584 so, then switch to that thread, and eventually give control back to
1587 Note that if there's any kind of pending follow (i.e., of a fork,
1588 vfork or exec), we don't want to do this now. Rather, we'll let
1589 the next resume handle it. */
1590 if (!ptid_equal (ecs->ptid, inferior_ptid) &&
1591 (pending_follow.kind == TARGET_WAITKIND_SPURIOUS))
1595 /* If it's a random signal for a non-current thread, notify user
1596 if he's expressed an interest. */
1597 if (ecs->random_signal && signal_print[stop_signal])
1599 /* ??rehrauer: I don't understand the rationale for this code. If the
1600 inferior will stop as a result of this signal, then the act of handling
1601 the stop ought to print a message that's couches the stoppage in user
1602 terms, e.g., "Stopped for breakpoint/watchpoint". If the inferior
1603 won't stop as a result of the signal -- i.e., if the signal is merely
1604 a side-effect of something GDB's doing "under the covers" for the
1605 user, such as stepping threads over a breakpoint they shouldn't stop
1606 for -- then the message seems to be a serious annoyance at best.
1608 For now, remove the message altogether. */
1611 target_terminal_ours_for_output ();
1612 printf_filtered ("\nProgram received signal %s, %s.\n",
1613 target_signal_to_name (stop_signal),
1614 target_signal_to_string (stop_signal));
1615 gdb_flush (gdb_stdout);
1619 /* If it's not SIGTRAP and not a signal we want to stop for, then
1620 continue the thread. */
1622 if (stop_signal != TARGET_SIGNAL_TRAP && !signal_stop[stop_signal])
1625 target_terminal_inferior ();
1627 /* Clear the signal if it should not be passed. */
1628 if (signal_program[stop_signal] == 0)
1629 stop_signal = TARGET_SIGNAL_0;
1631 target_resume (ecs->ptid, 0, stop_signal);
1632 prepare_to_wait (ecs);
1636 /* It's a SIGTRAP or a signal we're interested in. Switch threads,
1637 and fall into the rest of wait_for_inferior(). */
1639 context_switch (ecs);
1642 context_hook (pid_to_thread_id (ecs->ptid));
1644 flush_cached_frames ();
1647 if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
1649 /* Pull the single step breakpoints out of the target. */
1650 SOFTWARE_SINGLE_STEP (0, 0);
1651 singlestep_breakpoints_inserted_p = 0;
1654 /* If PC is pointing at a nullified instruction, then step beyond
1655 it so that the user won't be confused when GDB appears to be ready
1658 /* if (INSTRUCTION_NULLIFIED && currently_stepping (ecs)) */
1659 if (INSTRUCTION_NULLIFIED)
1661 registers_changed ();
1662 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1664 /* We may have received a signal that we want to pass to
1665 the inferior; therefore, we must not clobber the waitstatus
1668 ecs->infwait_state = infwait_nullified_state;
1669 ecs->waiton_ptid = ecs->ptid;
1670 ecs->wp = &(ecs->tmpstatus);
1671 prepare_to_wait (ecs);
1675 /* It may not be necessary to disable the watchpoint to stop over
1676 it. For example, the PA can (with some kernel cooperation)
1677 single step over a watchpoint without disabling the watchpoint. */
1678 if (HAVE_STEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
1681 prepare_to_wait (ecs);
1685 /* It is far more common to need to disable a watchpoint to step
1686 the inferior over it. FIXME. What else might a debug
1687 register or page protection watchpoint scheme need here? */
1688 if (HAVE_NONSTEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
1690 /* At this point, we are stopped at an instruction which has
1691 attempted to write to a piece of memory under control of
1692 a watchpoint. The instruction hasn't actually executed
1693 yet. If we were to evaluate the watchpoint expression
1694 now, we would get the old value, and therefore no change
1695 would seem to have occurred.
1697 In order to make watchpoints work `right', we really need
1698 to complete the memory write, and then evaluate the
1699 watchpoint expression. The following code does that by
1700 removing the watchpoint (actually, all watchpoints and
1701 breakpoints), single-stepping the target, re-inserting
1702 watchpoints, and then falling through to let normal
1703 single-step processing handle proceed. Since this
1704 includes evaluating watchpoints, things will come to a
1705 stop in the correct manner. */
1707 if (DECR_PC_AFTER_BREAK)
1708 write_pc (stop_pc - DECR_PC_AFTER_BREAK);
1710 remove_breakpoints ();
1711 registers_changed ();
1712 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */
1714 ecs->waiton_ptid = ecs->ptid;
1715 ecs->wp = &(ecs->ws);
1716 ecs->infwait_state = infwait_nonstep_watch_state;
1717 prepare_to_wait (ecs);
1721 /* It may be possible to simply continue after a watchpoint. */
1722 if (HAVE_CONTINUABLE_WATCHPOINT)
1723 STOPPED_BY_WATCHPOINT (ecs->ws);
1725 ecs->stop_func_start = 0;
1726 ecs->stop_func_end = 0;
1727 ecs->stop_func_name = 0;
1728 /* Don't care about return value; stop_func_start and stop_func_name
1729 will both be 0 if it doesn't work. */
1730 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
1731 &ecs->stop_func_start, &ecs->stop_func_end);
1732 ecs->stop_func_start += FUNCTION_START_OFFSET;
1733 ecs->another_trap = 0;
1734 bpstat_clear (&stop_bpstat);
1736 stop_stack_dummy = 0;
1737 stop_print_frame = 1;
1738 ecs->random_signal = 0;
1739 stopped_by_random_signal = 0;
1740 breakpoints_failed = 0;
1742 /* Look at the cause of the stop, and decide what to do.
1743 The alternatives are:
1744 1) break; to really stop and return to the debugger,
1745 2) drop through to start up again
1746 (set ecs->another_trap to 1 to single step once)
1747 3) set ecs->random_signal to 1, and the decision between 1 and 2
1748 will be made according to the signal handling tables. */
1750 /* First, distinguish signals caused by the debugger from signals
1751 that have to do with the program's own actions.
1752 Note that breakpoint insns may cause SIGTRAP or SIGILL
1753 or SIGEMT, depending on the operating system version.
1754 Here we detect when a SIGILL or SIGEMT is really a breakpoint
1755 and change it to SIGTRAP. */
1757 if (stop_signal == TARGET_SIGNAL_TRAP
1758 || (breakpoints_inserted &&
1759 (stop_signal == TARGET_SIGNAL_ILL
1760 || stop_signal == TARGET_SIGNAL_EMT))
1761 || stop_soon_quietly == STOP_QUIETLY
1762 || stop_soon_quietly == STOP_QUIETLY_NO_SIGSTOP)
1764 if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
1766 stop_print_frame = 0;
1767 stop_stepping (ecs);
1771 /* This is originated from start_remote(), start_inferior() and
1772 shared libraries hook functions. */
1773 if (stop_soon_quietly == STOP_QUIETLY)
1775 stop_stepping (ecs);
1779 /* This originates from attach_command(). We need to overwrite
1780 the stop_signal here, because some kernels don't ignore a
1781 SIGSTOP in a subsequent ptrace(PTRACE_SONT,SOGSTOP) call.
1782 See more comments in inferior.h. */
1783 if (stop_soon_quietly == STOP_QUIETLY_NO_SIGSTOP)
1785 stop_stepping (ecs);
1786 if (stop_signal == TARGET_SIGNAL_STOP)
1787 stop_signal = TARGET_SIGNAL_0;
1791 /* Don't even think about breakpoints
1792 if just proceeded over a breakpoint.
1794 However, if we are trying to proceed over a breakpoint
1795 and end up in sigtramp, then through_sigtramp_breakpoint
1796 will be set and we should check whether we've hit the
1798 if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected
1799 && through_sigtramp_breakpoint == NULL)
1800 bpstat_clear (&stop_bpstat);
1803 /* See if there is a breakpoint at the current PC. */
1805 /* The second argument of bpstat_stop_status is meant to help
1806 distinguish between a breakpoint trap and a singlestep trap.
1807 This is only important on targets where DECR_PC_AFTER_BREAK
1808 is non-zero. The prev_pc test is meant to distinguish between
1809 singlestepping a trap instruction, and singlestepping thru a
1810 jump to the instruction following a trap instruction.
1812 Therefore, pass TRUE if our reason for stopping is
1813 something other than hitting a breakpoint. We do this by
1814 checking that either: we detected earlier a software single
1815 step trap or, 1) stepping is going on and 2) we didn't hit
1816 a breakpoint in a signal handler without an intervening stop
1817 in sigtramp, which is detected by a new stack pointer value
1818 below any usual function calling stack adjustments. */
1822 sw_single_step_trap_p
1823 || (currently_stepping (ecs)
1824 && prev_pc != stop_pc - DECR_PC_AFTER_BREAK
1826 && INNER_THAN (read_sp (), (step_sp - 16)))));
1827 /* Following in case break condition called a
1829 stop_print_frame = 1;
1832 /* NOTE: cagney/2003-03-29: These two checks for a random signal
1833 at one stage in the past included checks for an inferior
1834 function call's call dummy's return breakpoint. The original
1835 comment, that went with the test, read:
1837 ``End of a stack dummy. Some systems (e.g. Sony news) give
1838 another signal besides SIGTRAP, so check here as well as
1841 If someone ever tries to get get call dummys on a
1842 non-executable stack to work (where the target would stop
1843 with something like a SIGSEG), then those tests might need to
1844 be re-instated. Given, however, that the tests were only
1845 enabled when momentary breakpoints were not being used, I
1846 suspect that it won't be the case. */
1848 if (stop_signal == TARGET_SIGNAL_TRAP)
1850 = !(bpstat_explains_signal (stop_bpstat)
1852 || (step_range_end && step_resume_breakpoint == NULL));
1855 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1856 if (!ecs->random_signal)
1857 stop_signal = TARGET_SIGNAL_TRAP;
1861 /* When we reach this point, we've pretty much decided
1862 that the reason for stopping must've been a random
1863 (unexpected) signal. */
1866 ecs->random_signal = 1;
1868 process_event_stop_test:
1869 /* For the program's own signals, act according to
1870 the signal handling tables. */
1872 if (ecs->random_signal)
1874 /* Signal not for debugging purposes. */
1877 stopped_by_random_signal = 1;
1879 if (signal_print[stop_signal])
1882 target_terminal_ours_for_output ();
1883 print_stop_reason (SIGNAL_RECEIVED, stop_signal);
1885 if (signal_stop[stop_signal])
1887 stop_stepping (ecs);
1890 /* If not going to stop, give terminal back
1891 if we took it away. */
1893 target_terminal_inferior ();
1895 /* Clear the signal if it should not be passed. */
1896 if (signal_program[stop_signal] == 0)
1897 stop_signal = TARGET_SIGNAL_0;
1899 /* I'm not sure whether this needs to be check_sigtramp2 or
1900 whether it could/should be keep_going.
1902 This used to jump to step_over_function if we are stepping,
1905 Suppose the user does a `next' over a function call, and while
1906 that call is in progress, the inferior receives a signal for
1907 which GDB does not stop (i.e., signal_stop[SIG] is false). In
1908 that case, when we reach this point, there is already a
1909 step-resume breakpoint established, right where it should be:
1910 immediately after the function call the user is "next"-ing
1911 over. If we call step_over_function now, two bad things
1914 - we'll create a new breakpoint, at wherever the current
1915 frame's return address happens to be. That could be
1916 anywhere, depending on what function call happens to be on
1917 the top of the stack at that point. Point is, it's probably
1918 not where we need it.
1920 - the existing step-resume breakpoint (which is at the correct
1921 address) will get orphaned: step_resume_breakpoint will point
1922 to the new breakpoint, and the old step-resume breakpoint
1923 will never be cleaned up.
1925 The old behavior was meant to help HP-UX single-step out of
1926 sigtramps. It would place the new breakpoint at prev_pc, which
1927 was certainly wrong. I don't know the details there, so fixing
1928 this probably breaks that. As with anything else, it's up to
1929 the HP-UX maintainer to furnish a fix that doesn't break other
1930 platforms. --JimB, 20 May 1999 */
1931 check_sigtramp2 (ecs);
1936 /* Handle cases caused by hitting a breakpoint. */
1938 CORE_ADDR jmp_buf_pc;
1939 struct bpstat_what what;
1941 what = bpstat_what (stop_bpstat);
1943 if (what.call_dummy)
1945 stop_stack_dummy = 1;
1947 trap_expected_after_continue = 1;
1951 switch (what.main_action)
1953 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
1954 /* If we hit the breakpoint at longjmp, disable it for the
1955 duration of this command. Then, install a temporary
1956 breakpoint at the target of the jmp_buf. */
1957 disable_longjmp_breakpoint ();
1958 remove_breakpoints ();
1959 breakpoints_inserted = 0;
1960 if (!GET_LONGJMP_TARGET_P () || !GET_LONGJMP_TARGET (&jmp_buf_pc))
1966 /* Need to blow away step-resume breakpoint, as it
1967 interferes with us */
1968 if (step_resume_breakpoint != NULL)
1970 delete_step_resume_breakpoint (&step_resume_breakpoint);
1972 /* Not sure whether we need to blow this away too, but probably
1973 it is like the step-resume breakpoint. */
1974 if (through_sigtramp_breakpoint != NULL)
1976 delete_breakpoint (through_sigtramp_breakpoint);
1977 through_sigtramp_breakpoint = NULL;
1981 /* FIXME - Need to implement nested temporary breakpoints */
1982 if (step_over_calls > 0)
1983 set_longjmp_resume_breakpoint (jmp_buf_pc, get_current_frame ());
1986 set_longjmp_resume_breakpoint (jmp_buf_pc, null_frame_id);
1987 ecs->handling_longjmp = 1; /* FIXME */
1991 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
1992 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
1993 remove_breakpoints ();
1994 breakpoints_inserted = 0;
1996 /* FIXME - Need to implement nested temporary breakpoints */
1998 && (frame_id_inner (get_frame_id (get_current_frame ()),
2001 ecs->another_trap = 1;
2006 disable_longjmp_breakpoint ();
2007 ecs->handling_longjmp = 0; /* FIXME */
2008 if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
2010 /* else fallthrough */
2012 case BPSTAT_WHAT_SINGLE:
2013 if (breakpoints_inserted)
2015 remove_breakpoints ();
2017 breakpoints_inserted = 0;
2018 ecs->another_trap = 1;
2019 /* Still need to check other stuff, at least the case
2020 where we are stepping and step out of the right range. */
2023 case BPSTAT_WHAT_STOP_NOISY:
2024 stop_print_frame = 1;
2026 /* We are about to nuke the step_resume_breakpoint and
2027 through_sigtramp_breakpoint via the cleanup chain, so
2028 no need to worry about it here. */
2030 stop_stepping (ecs);
2033 case BPSTAT_WHAT_STOP_SILENT:
2034 stop_print_frame = 0;
2036 /* We are about to nuke the step_resume_breakpoint and
2037 through_sigtramp_breakpoint via the cleanup chain, so
2038 no need to worry about it here. */
2040 stop_stepping (ecs);
2043 case BPSTAT_WHAT_STEP_RESUME:
2044 /* This proably demands a more elegant solution, but, yeah
2047 This function's use of the simple variable
2048 step_resume_breakpoint doesn't seem to accomodate
2049 simultaneously active step-resume bp's, although the
2050 breakpoint list certainly can.
2052 If we reach here and step_resume_breakpoint is already
2053 NULL, then apparently we have multiple active
2054 step-resume bp's. We'll just delete the breakpoint we
2055 stopped at, and carry on.
2057 Correction: what the code currently does is delete a
2058 step-resume bp, but it makes no effort to ensure that
2059 the one deleted is the one currently stopped at. MVS */
2061 if (step_resume_breakpoint == NULL)
2063 step_resume_breakpoint =
2064 bpstat_find_step_resume_breakpoint (stop_bpstat);
2066 delete_step_resume_breakpoint (&step_resume_breakpoint);
2069 case BPSTAT_WHAT_THROUGH_SIGTRAMP:
2070 if (through_sigtramp_breakpoint)
2071 delete_breakpoint (through_sigtramp_breakpoint);
2072 through_sigtramp_breakpoint = NULL;
2074 /* If were waiting for a trap, hitting the step_resume_break
2075 doesn't count as getting it. */
2077 ecs->another_trap = 1;
2080 case BPSTAT_WHAT_CHECK_SHLIBS:
2081 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
2084 /* Remove breakpoints, we eventually want to step over the
2085 shlib event breakpoint, and SOLIB_ADD might adjust
2086 breakpoint addresses via breakpoint_re_set. */
2087 if (breakpoints_inserted)
2088 remove_breakpoints ();
2089 breakpoints_inserted = 0;
2091 /* Check for any newly added shared libraries if we're
2092 supposed to be adding them automatically. Switch
2093 terminal for any messages produced by
2094 breakpoint_re_set. */
2095 target_terminal_ours_for_output ();
2096 SOLIB_ADD (NULL, 0, NULL, auto_solib_add);
2097 target_terminal_inferior ();
2099 /* Try to reenable shared library breakpoints, additional
2100 code segments in shared libraries might be mapped in now. */
2101 re_enable_breakpoints_in_shlibs ();
2103 /* If requested, stop when the dynamic linker notifies
2104 gdb of events. This allows the user to get control
2105 and place breakpoints in initializer routines for
2106 dynamically loaded objects (among other things). */
2107 if (stop_on_solib_events)
2109 stop_stepping (ecs);
2113 /* If we stopped due to an explicit catchpoint, then the
2114 (see above) call to SOLIB_ADD pulled in any symbols
2115 from a newly-loaded library, if appropriate.
2117 We do want the inferior to stop, but not where it is
2118 now, which is in the dynamic linker callback. Rather,
2119 we would like it stop in the user's program, just after
2120 the call that caused this catchpoint to trigger. That
2121 gives the user a more useful vantage from which to
2122 examine their program's state. */
2123 else if (what.main_action ==
2124 BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
2126 /* ??rehrauer: If I could figure out how to get the
2127 right return PC from here, we could just set a temp
2128 breakpoint and resume. I'm not sure we can without
2129 cracking open the dld's shared libraries and sniffing
2130 their unwind tables and text/data ranges, and that's
2131 not a terribly portable notion.
2133 Until that time, we must step the inferior out of the
2134 dld callback, and also out of the dld itself (and any
2135 code or stubs in libdld.sl, such as "shl_load" and
2136 friends) until we reach non-dld code. At that point,
2137 we can stop stepping. */
2138 bpstat_get_triggered_catchpoints (stop_bpstat,
2140 stepping_through_solib_catchpoints);
2141 ecs->stepping_through_solib_after_catch = 1;
2143 /* Be sure to lift all breakpoints, so the inferior does
2144 actually step past this point... */
2145 ecs->another_trap = 1;
2150 /* We want to step over this breakpoint, then keep going. */
2151 ecs->another_trap = 1;
2158 case BPSTAT_WHAT_LAST:
2159 /* Not a real code, but listed here to shut up gcc -Wall. */
2161 case BPSTAT_WHAT_KEEP_CHECKING:
2166 /* We come here if we hit a breakpoint but should not
2167 stop for it. Possibly we also were stepping
2168 and should stop for that. So fall through and
2169 test for stepping. But, if not stepping,
2172 /* Are we stepping to get the inferior out of the dynamic
2173 linker's hook (and possibly the dld itself) after catching
2175 if (ecs->stepping_through_solib_after_catch)
2177 #if defined(SOLIB_ADD)
2178 /* Have we reached our destination? If not, keep going. */
2179 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc))
2181 ecs->another_trap = 1;
2186 /* Else, stop and report the catchpoint(s) whose triggering
2187 caused us to begin stepping. */
2188 ecs->stepping_through_solib_after_catch = 0;
2189 bpstat_clear (&stop_bpstat);
2190 stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints);
2191 bpstat_clear (&ecs->stepping_through_solib_catchpoints);
2192 stop_print_frame = 1;
2193 stop_stepping (ecs);
2197 if (step_resume_breakpoint)
2199 /* Having a step-resume breakpoint overrides anything
2200 else having to do with stepping commands until
2201 that breakpoint is reached. */
2202 /* I'm not sure whether this needs to be check_sigtramp2 or
2203 whether it could/should be keep_going. */
2204 check_sigtramp2 (ecs);
2209 if (step_range_end == 0)
2211 /* Likewise if we aren't even stepping. */
2212 /* I'm not sure whether this needs to be check_sigtramp2 or
2213 whether it could/should be keep_going. */
2214 check_sigtramp2 (ecs);
2219 /* If stepping through a line, keep going if still within it.
2221 Note that step_range_end is the address of the first instruction
2222 beyond the step range, and NOT the address of the last instruction
2224 if (stop_pc >= step_range_start && stop_pc < step_range_end)
2226 /* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal.
2227 So definately need to check for sigtramp here. */
2228 check_sigtramp2 (ecs);
2233 /* We stepped out of the stepping range. */
2235 /* If we are stepping at the source level and entered the runtime
2236 loader dynamic symbol resolution code, we keep on single stepping
2237 until we exit the run time loader code and reach the callee's
2239 if (step_over_calls == STEP_OVER_UNDEBUGGABLE
2240 && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc))
2242 CORE_ADDR pc_after_resolver = SKIP_SOLIB_RESOLVER (stop_pc);
2244 if (pc_after_resolver)
2246 /* Set up a step-resume breakpoint at the address
2247 indicated by SKIP_SOLIB_RESOLVER. */
2248 struct symtab_and_line sr_sal;
2250 sr_sal.pc = pc_after_resolver;
2252 check_for_old_step_resume_breakpoint ();
2253 step_resume_breakpoint =
2254 set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
2255 if (breakpoints_inserted)
2256 insert_breakpoints ();
2263 /* We can't update step_sp every time through the loop, because
2264 reading the stack pointer would slow down stepping too much.
2265 But we can update it every time we leave the step range. */
2266 ecs->update_step_sp = 1;
2268 /* Did we just take a signal? */
2269 if (PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2270 && !PC_IN_SIGTRAMP (prev_pc, prev_func_name)
2271 && INNER_THAN (read_sp (), step_sp))
2273 /* We've just taken a signal; go until we are back to
2274 the point where we took it and one more. */
2276 /* Note: The test above succeeds not only when we stepped
2277 into a signal handler, but also when we step past the last
2278 statement of a signal handler and end up in the return stub
2279 of the signal handler trampoline. To distinguish between
2280 these two cases, check that the frame is INNER_THAN the
2281 previous one below. pai/1997-09-11 */
2285 struct frame_id current_frame = get_frame_id (get_current_frame ());
2287 if (frame_id_inner (current_frame, step_frame_id))
2289 /* We have just taken a signal; go until we are back to
2290 the point where we took it and one more. */
2292 /* This code is needed at least in the following case:
2293 The user types "next" and then a signal arrives (before
2294 the "next" is done). */
2296 /* Note that if we are stopped at a breakpoint, then we need
2297 the step_resume breakpoint to override any breakpoints at
2298 the same location, so that we will still step over the
2299 breakpoint even though the signal happened. */
2300 struct symtab_and_line sr_sal;
2303 sr_sal.symtab = NULL;
2305 sr_sal.pc = prev_pc;
2306 /* We could probably be setting the frame to
2307 step_frame_id; I don't think anyone thought to try it. */
2308 check_for_old_step_resume_breakpoint ();
2309 step_resume_breakpoint =
2310 set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
2311 if (breakpoints_inserted)
2312 insert_breakpoints ();
2316 /* We just stepped out of a signal handler and into
2317 its calling trampoline.
2319 Normally, we'd call step_over_function from
2320 here, but for some reason GDB can't unwind the
2321 stack correctly to find the real PC for the point
2322 user code where the signal trampoline will return
2323 -- FRAME_SAVED_PC fails, at least on HP-UX 10.20.
2324 But signal trampolines are pretty small stubs of
2325 code, anyway, so it's OK instead to just
2326 single-step out. Note: assuming such trampolines
2327 don't exhibit recursion on any platform... */
2328 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
2329 &ecs->stop_func_start,
2330 &ecs->stop_func_end);
2331 /* Readjust stepping range */
2332 step_range_start = ecs->stop_func_start;
2333 step_range_end = ecs->stop_func_end;
2334 ecs->stepping_through_sigtramp = 1;
2339 /* If this is stepi or nexti, make sure that the stepping range
2340 gets us past that instruction. */
2341 if (step_range_end == 1)
2342 /* FIXME: Does this run afoul of the code below which, if
2343 we step into the middle of a line, resets the stepping
2345 step_range_end = (step_range_start = prev_pc) + 1;
2347 ecs->remove_breakpoints_on_following_step = 1;
2352 if (stop_pc == ecs->stop_func_start /* Quick test */
2353 || (in_prologue (stop_pc, ecs->stop_func_start) &&
2354 !IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2355 || IN_SOLIB_CALL_TRAMPOLINE (stop_pc, ecs->stop_func_name)
2356 || ecs->stop_func_name == 0)
2358 /* It's a subroutine call. */
2360 if ((step_over_calls == STEP_OVER_NONE)
2361 || ((step_range_end == 1)
2362 && in_prologue (prev_pc, ecs->stop_func_start)))
2364 /* I presume that step_over_calls is only 0 when we're
2365 supposed to be stepping at the assembly language level
2366 ("stepi"). Just stop. */
2367 /* Also, maybe we just did a "nexti" inside a prolog,
2368 so we thought it was a subroutine call but it was not.
2369 Stop as well. FENN */
2371 print_stop_reason (END_STEPPING_RANGE, 0);
2372 stop_stepping (ecs);
2376 if (step_over_calls == STEP_OVER_ALL || IGNORE_HELPER_CALL (stop_pc))
2378 /* We're doing a "next". */
2380 if (PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2381 && frame_id_inner (step_frame_id,
2382 frame_id_build (read_sp (), 0)))
2383 /* We stepped out of a signal handler, and into its
2384 calling trampoline. This is misdetected as a
2385 subroutine call, but stepping over the signal
2386 trampoline isn't such a bad idea. In order to do that,
2387 we have to ignore the value in step_frame_id, since
2388 that doesn't represent the frame that'll reach when we
2389 return from the signal trampoline. Otherwise we'll
2390 probably continue to the end of the program. */
2391 step_frame_id = null_frame_id;
2393 step_over_function (ecs);
2398 /* If we are in a function call trampoline (a stub between
2399 the calling routine and the real function), locate the real
2400 function. That's what tells us (a) whether we want to step
2401 into it at all, and (b) what prologue we want to run to
2402 the end of, if we do step into it. */
2403 real_stop_pc = skip_language_trampoline (stop_pc);
2404 if (real_stop_pc == 0)
2405 real_stop_pc = SKIP_TRAMPOLINE_CODE (stop_pc);
2406 if (real_stop_pc != 0)
2407 ecs->stop_func_start = real_stop_pc;
2409 /* If we have line number information for the function we
2410 are thinking of stepping into, step into it.
2412 If there are several symtabs at that PC (e.g. with include
2413 files), just want to know whether *any* of them have line
2414 numbers. find_pc_line handles this. */
2416 struct symtab_and_line tmp_sal;
2418 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
2419 if (tmp_sal.line != 0)
2421 step_into_function (ecs);
2426 /* If we have no line number and the step-stop-if-no-debug
2427 is set, we stop the step so that the user has a chance to
2428 switch in assembly mode. */
2429 if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug)
2432 print_stop_reason (END_STEPPING_RANGE, 0);
2433 stop_stepping (ecs);
2437 step_over_function (ecs);
2443 /* We've wandered out of the step range. */
2445 ecs->sal = find_pc_line (stop_pc, 0);
2447 if (step_range_end == 1)
2449 /* It is stepi or nexti. We always want to stop stepping after
2452 print_stop_reason (END_STEPPING_RANGE, 0);
2453 stop_stepping (ecs);
2457 /* If we're in the return path from a shared library trampoline,
2458 we want to proceed through the trampoline when stepping. */
2459 if (IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2461 /* Determine where this trampoline returns. */
2462 real_stop_pc = SKIP_TRAMPOLINE_CODE (stop_pc);
2464 /* Only proceed through if we know where it's going. */
2467 /* And put the step-breakpoint there and go until there. */
2468 struct symtab_and_line sr_sal;
2470 init_sal (&sr_sal); /* initialize to zeroes */
2471 sr_sal.pc = real_stop_pc;
2472 sr_sal.section = find_pc_overlay (sr_sal.pc);
2473 /* Do not specify what the fp should be when we stop
2474 since on some machines the prologue
2475 is where the new fp value is established. */
2476 check_for_old_step_resume_breakpoint ();
2477 step_resume_breakpoint =
2478 set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
2479 if (breakpoints_inserted)
2480 insert_breakpoints ();
2482 /* Restart without fiddling with the step ranges or
2489 if (ecs->sal.line == 0)
2491 /* We have no line number information. That means to stop
2492 stepping (does this always happen right after one instruction,
2493 when we do "s" in a function with no line numbers,
2494 or can this happen as a result of a return or longjmp?). */
2496 print_stop_reason (END_STEPPING_RANGE, 0);
2497 stop_stepping (ecs);
2501 if ((stop_pc == ecs->sal.pc)
2502 && (ecs->current_line != ecs->sal.line
2503 || ecs->current_symtab != ecs->sal.symtab))
2505 /* We are at the start of a different line. So stop. Note that
2506 we don't stop if we step into the middle of a different line.
2507 That is said to make things like for (;;) statements work
2510 print_stop_reason (END_STEPPING_RANGE, 0);
2511 stop_stepping (ecs);
2515 /* We aren't done stepping.
2517 Optimize by setting the stepping range to the line.
2518 (We might not be in the original line, but if we entered a
2519 new line in mid-statement, we continue stepping. This makes
2520 things like for(;;) statements work better.) */
2522 if (ecs->stop_func_end && ecs->sal.end >= ecs->stop_func_end)
2524 /* If this is the last line of the function, don't keep stepping
2525 (it would probably step us out of the function).
2526 This is particularly necessary for a one-line function,
2527 in which after skipping the prologue we better stop even though
2528 we will be in mid-line. */
2530 print_stop_reason (END_STEPPING_RANGE, 0);
2531 stop_stepping (ecs);
2534 step_range_start = ecs->sal.pc;
2535 step_range_end = ecs->sal.end;
2536 step_frame_id = get_frame_id (get_current_frame ());
2537 ecs->current_line = ecs->sal.line;
2538 ecs->current_symtab = ecs->sal.symtab;
2540 /* In the case where we just stepped out of a function into the
2541 middle of a line of the caller, continue stepping, but
2542 step_frame_id must be modified to current frame */
2544 struct frame_id current_frame = get_frame_id (get_current_frame ());
2545 if (!(frame_id_inner (current_frame, step_frame_id)))
2546 step_frame_id = current_frame;
2552 /* Are we in the middle of stepping? */
2555 currently_stepping (struct execution_control_state *ecs)
2557 return ((through_sigtramp_breakpoint == NULL
2558 && !ecs->handling_longjmp
2559 && ((step_range_end && step_resume_breakpoint == NULL)
2561 || ecs->stepping_through_solib_after_catch
2562 || bpstat_should_step ());
2566 check_sigtramp2 (struct execution_control_state *ecs)
2569 && PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2570 && !PC_IN_SIGTRAMP (prev_pc, prev_func_name)
2571 && INNER_THAN (read_sp (), step_sp))
2573 /* What has happened here is that we have just stepped the
2574 inferior with a signal (because it is a signal which
2575 shouldn't make us stop), thus stepping into sigtramp.
2577 So we need to set a step_resume_break_address breakpoint and
2578 continue until we hit it, and then step. FIXME: This should
2579 be more enduring than a step_resume breakpoint; we should
2580 know that we will later need to keep going rather than
2581 re-hitting the breakpoint here (see the testsuite,
2582 gdb.base/signals.exp where it says "exceedingly difficult"). */
2584 struct symtab_and_line sr_sal;
2586 init_sal (&sr_sal); /* initialize to zeroes */
2587 sr_sal.pc = prev_pc;
2588 sr_sal.section = find_pc_overlay (sr_sal.pc);
2589 /* We perhaps could set the frame if we kept track of what the
2590 frame corresponding to prev_pc was. But we don't, so don't. */
2591 through_sigtramp_breakpoint =
2592 set_momentary_breakpoint (sr_sal, null_frame_id, bp_through_sigtramp);
2593 if (breakpoints_inserted)
2594 insert_breakpoints ();
2596 ecs->remove_breakpoints_on_following_step = 1;
2597 ecs->another_trap = 1;
2601 /* Subroutine call with source code we should not step over. Do step
2602 to the first line of code in it. */
2605 step_into_function (struct execution_control_state *ecs)
2608 struct symtab_and_line sr_sal;
2610 s = find_pc_symtab (stop_pc);
2611 if (s && s->language != language_asm)
2612 ecs->stop_func_start = SKIP_PROLOGUE (ecs->stop_func_start);
2614 ecs->sal = find_pc_line (ecs->stop_func_start, 0);
2615 /* Use the step_resume_break to step until the end of the prologue,
2616 even if that involves jumps (as it seems to on the vax under
2618 /* If the prologue ends in the middle of a source line, continue to
2619 the end of that source line (if it is still within the function).
2620 Otherwise, just go to end of prologue. */
2621 #ifdef PROLOGUE_FIRSTLINE_OVERLAP
2622 /* no, don't either. It skips any code that's legitimately on the
2626 && ecs->sal.pc != ecs->stop_func_start
2627 && ecs->sal.end < ecs->stop_func_end)
2628 ecs->stop_func_start = ecs->sal.end;
2631 if (ecs->stop_func_start == stop_pc)
2633 /* We are already there: stop now. */
2635 print_stop_reason (END_STEPPING_RANGE, 0);
2636 stop_stepping (ecs);
2641 /* Put the step-breakpoint there and go until there. */
2642 init_sal (&sr_sal); /* initialize to zeroes */
2643 sr_sal.pc = ecs->stop_func_start;
2644 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
2645 /* Do not specify what the fp should be when we stop since on
2646 some machines the prologue is where the new fp value is
2648 check_for_old_step_resume_breakpoint ();
2649 step_resume_breakpoint =
2650 set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
2651 if (breakpoints_inserted)
2652 insert_breakpoints ();
2654 /* And make sure stepping stops right away then. */
2655 step_range_end = step_range_start;
2660 /* We've just entered a callee, and we wish to resume until it returns
2661 to the caller. Setting a step_resume breakpoint on the return
2662 address will catch a return from the callee.
2664 However, if the callee is recursing, we want to be careful not to
2665 catch returns of those recursive calls, but only of THIS instance
2668 To do this, we set the step_resume bp's frame to our current
2669 caller's frame (step_frame_id, which is set by the "next" or
2670 "until" command, before execution begins). */
2673 step_over_function (struct execution_control_state *ecs)
2675 struct symtab_and_line sr_sal;
2677 init_sal (&sr_sal); /* initialize to zeros */
2678 sr_sal.pc = ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ()));
2679 sr_sal.section = find_pc_overlay (sr_sal.pc);
2681 check_for_old_step_resume_breakpoint ();
2682 step_resume_breakpoint =
2683 set_momentary_breakpoint (sr_sal, get_frame_id (get_current_frame ()),
2686 if (frame_id_p (step_frame_id)
2687 && !IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
2688 step_resume_breakpoint->frame_id = step_frame_id;
2690 if (breakpoints_inserted)
2691 insert_breakpoints ();
2695 stop_stepping (struct execution_control_state *ecs)
2697 if (target_has_execution)
2699 /* Assuming the inferior still exists, set these up for next
2700 time, just like we did above if we didn't break out of the
2702 prev_pc = read_pc ();
2703 prev_func_start = ecs->stop_func_start;
2704 prev_func_name = ecs->stop_func_name;
2707 /* Let callers know we don't want to wait for the inferior anymore. */
2708 ecs->wait_some_more = 0;
2711 /* This function handles various cases where we need to continue
2712 waiting for the inferior. */
2713 /* (Used to be the keep_going: label in the old wait_for_inferior) */
2716 keep_going (struct execution_control_state *ecs)
2718 /* Save the pc before execution, to compare with pc after stop. */
2719 prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
2720 prev_func_start = ecs->stop_func_start; /* Ok, since if DECR_PC_AFTER
2721 BREAK is defined, the
2722 original pc would not have
2723 been at the start of a
2725 prev_func_name = ecs->stop_func_name;
2727 if (ecs->update_step_sp)
2728 step_sp = read_sp ();
2729 ecs->update_step_sp = 0;
2731 /* If we did not do break;, it means we should keep running the
2732 inferior and not return to debugger. */
2734 if (trap_expected && stop_signal != TARGET_SIGNAL_TRAP)
2736 /* We took a signal (which we are supposed to pass through to
2737 the inferior, else we'd have done a break above) and we
2738 haven't yet gotten our trap. Simply continue. */
2739 resume (currently_stepping (ecs), stop_signal);
2743 /* Either the trap was not expected, but we are continuing
2744 anyway (the user asked that this signal be passed to the
2747 The signal was SIGTRAP, e.g. it was our signal, but we
2748 decided we should resume from it.
2750 We're going to run this baby now!
2752 Insert breakpoints now, unless we are trying to one-proceed
2753 past a breakpoint. */
2754 /* If we've just finished a special step resume and we don't
2755 want to hit a breakpoint, pull em out. */
2756 if (step_resume_breakpoint == NULL
2757 && through_sigtramp_breakpoint == NULL
2758 && ecs->remove_breakpoints_on_following_step)
2760 ecs->remove_breakpoints_on_following_step = 0;
2761 remove_breakpoints ();
2762 breakpoints_inserted = 0;
2764 else if (!breakpoints_inserted &&
2765 (through_sigtramp_breakpoint != NULL || !ecs->another_trap))
2767 breakpoints_failed = insert_breakpoints ();
2768 if (breakpoints_failed)
2770 stop_stepping (ecs);
2773 breakpoints_inserted = 1;
2776 trap_expected = ecs->another_trap;
2778 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
2779 specifies that such a signal should be delivered to the
2782 Typically, this would occure when a user is debugging a
2783 target monitor on a simulator: the target monitor sets a
2784 breakpoint; the simulator encounters this break-point and
2785 halts the simulation handing control to GDB; GDB, noteing
2786 that the break-point isn't valid, returns control back to the
2787 simulator; the simulator then delivers the hardware
2788 equivalent of a SIGNAL_TRAP to the program being debugged. */
2790 if (stop_signal == TARGET_SIGNAL_TRAP && !signal_program[stop_signal])
2791 stop_signal = TARGET_SIGNAL_0;
2793 #ifdef SHIFT_INST_REGS
2794 /* I'm not sure when this following segment applies. I do know,
2795 now, that we shouldn't rewrite the regs when we were stopped
2796 by a random signal from the inferior process. */
2797 /* FIXME: Shouldn't this be based on the valid bit of the SXIP?
2798 (this is only used on the 88k). */
2800 if (!bpstat_explains_signal (stop_bpstat)
2801 && (stop_signal != TARGET_SIGNAL_CHLD) && !stopped_by_random_signal)
2803 #endif /* SHIFT_INST_REGS */
2805 resume (currently_stepping (ecs), stop_signal);
2808 prepare_to_wait (ecs);
2811 /* This function normally comes after a resume, before
2812 handle_inferior_event exits. It takes care of any last bits of
2813 housekeeping, and sets the all-important wait_some_more flag. */
2816 prepare_to_wait (struct execution_control_state *ecs)
2818 if (ecs->infwait_state == infwait_normal_state)
2820 overlay_cache_invalid = 1;
2822 /* We have to invalidate the registers BEFORE calling
2823 target_wait because they can be loaded from the target while
2824 in target_wait. This makes remote debugging a bit more
2825 efficient for those targets that provide critical registers
2826 as part of their normal status mechanism. */
2828 registers_changed ();
2829 ecs->waiton_ptid = pid_to_ptid (-1);
2830 ecs->wp = &(ecs->ws);
2832 /* This is the old end of the while loop. Let everybody know we
2833 want to wait for the inferior some more and get called again
2835 ecs->wait_some_more = 1;
2838 /* Print why the inferior has stopped. We always print something when
2839 the inferior exits, or receives a signal. The rest of the cases are
2840 dealt with later on in normal_stop() and print_it_typical(). Ideally
2841 there should be a call to this function from handle_inferior_event()
2842 each time stop_stepping() is called.*/
2844 print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
2846 switch (stop_reason)
2849 /* We don't deal with these cases from handle_inferior_event()
2852 case END_STEPPING_RANGE:
2853 /* We are done with a step/next/si/ni command. */
2854 /* For now print nothing. */
2855 /* Print a message only if not in the middle of doing a "step n"
2856 operation for n > 1 */
2857 if (!step_multi || !stop_step)
2858 if (ui_out_is_mi_like_p (uiout))
2859 ui_out_field_string (uiout, "reason", "end-stepping-range");
2861 case BREAKPOINT_HIT:
2862 /* We found a breakpoint. */
2863 /* For now print nothing. */
2866 /* The inferior was terminated by a signal. */
2867 annotate_signalled ();
2868 if (ui_out_is_mi_like_p (uiout))
2869 ui_out_field_string (uiout, "reason", "exited-signalled");
2870 ui_out_text (uiout, "\nProgram terminated with signal ");
2871 annotate_signal_name ();
2872 ui_out_field_string (uiout, "signal-name",
2873 target_signal_to_name (stop_info));
2874 annotate_signal_name_end ();
2875 ui_out_text (uiout, ", ");
2876 annotate_signal_string ();
2877 ui_out_field_string (uiout, "signal-meaning",
2878 target_signal_to_string (stop_info));
2879 annotate_signal_string_end ();
2880 ui_out_text (uiout, ".\n");
2881 ui_out_text (uiout, "The program no longer exists.\n");
2884 /* The inferior program is finished. */
2885 annotate_exited (stop_info);
2888 if (ui_out_is_mi_like_p (uiout))
2889 ui_out_field_string (uiout, "reason", "exited");
2890 ui_out_text (uiout, "\nProgram exited with code ");
2891 ui_out_field_fmt (uiout, "exit-code", "0%o",
2892 (unsigned int) stop_info);
2893 ui_out_text (uiout, ".\n");
2897 if (ui_out_is_mi_like_p (uiout))
2898 ui_out_field_string (uiout, "reason", "exited-normally");
2899 ui_out_text (uiout, "\nProgram exited normally.\n");
2902 case SIGNAL_RECEIVED:
2903 /* Signal received. The signal table tells us to print about
2906 ui_out_text (uiout, "\nProgram received signal ");
2907 annotate_signal_name ();
2908 if (ui_out_is_mi_like_p (uiout))
2909 ui_out_field_string (uiout, "reason", "signal-received");
2910 ui_out_field_string (uiout, "signal-name",
2911 target_signal_to_name (stop_info));
2912 annotate_signal_name_end ();
2913 ui_out_text (uiout, ", ");
2914 annotate_signal_string ();
2915 ui_out_field_string (uiout, "signal-meaning",
2916 target_signal_to_string (stop_info));
2917 annotate_signal_string_end ();
2918 ui_out_text (uiout, ".\n");
2921 internal_error (__FILE__, __LINE__,
2922 "print_stop_reason: unrecognized enum value");
2928 /* Here to return control to GDB when the inferior stops for real.
2929 Print appropriate messages, remove breakpoints, give terminal our modes.
2931 STOP_PRINT_FRAME nonzero means print the executing frame
2932 (pc, function, args, file, line number and line text).
2933 BREAKPOINTS_FAILED nonzero means stop was due to error
2934 attempting to insert breakpoints. */
2939 /* As with the notification of thread events, we want to delay
2940 notifying the user that we've switched thread context until
2941 the inferior actually stops.
2943 (Note that there's no point in saying anything if the inferior
2945 if (!ptid_equal (previous_inferior_ptid, inferior_ptid)
2946 && target_has_execution)
2948 target_terminal_ours_for_output ();
2949 printf_filtered ("[Switching to %s]\n",
2950 target_pid_or_tid_to_str (inferior_ptid));
2951 previous_inferior_ptid = inferior_ptid;
2954 /* Make sure that the current_frame's pc is correct. This
2955 is a correction for setting up the frame info before doing
2956 DECR_PC_AFTER_BREAK */
2957 if (target_has_execution)
2958 /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
2959 DECR_PC_AFTER_BREAK, the program counter can change. Ask the
2960 frame code to check for this and sort out any resultant mess.
2961 DECR_PC_AFTER_BREAK needs to just go away. */
2962 deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
2964 if (target_has_execution && breakpoints_inserted)
2966 if (remove_breakpoints ())
2968 target_terminal_ours_for_output ();
2969 printf_filtered ("Cannot remove breakpoints because ");
2970 printf_filtered ("program is no longer writable.\n");
2971 printf_filtered ("It might be running in another process.\n");
2972 printf_filtered ("Further execution is probably impossible.\n");
2975 breakpoints_inserted = 0;
2977 /* Delete the breakpoint we stopped at, if it wants to be deleted.
2978 Delete any breakpoint that is to be deleted at the next stop. */
2980 breakpoint_auto_delete (stop_bpstat);
2982 /* If an auto-display called a function and that got a signal,
2983 delete that auto-display to avoid an infinite recursion. */
2985 if (stopped_by_random_signal)
2986 disable_current_display ();
2988 /* Don't print a message if in the middle of doing a "step n"
2989 operation for n > 1 */
2990 if (step_multi && stop_step)
2993 target_terminal_ours ();
2995 /* Look up the hook_stop and run it (CLI internally handles problem
2996 of stop_command's pre-hook not existing). */
2998 catch_errors (hook_stop_stub, stop_command,
2999 "Error while running hook_stop:\n", RETURN_MASK_ALL);
3001 if (!target_has_stack)
3007 /* Select innermost stack frame - i.e., current frame is frame 0,
3008 and current location is based on that.
3009 Don't do this on return from a stack dummy routine,
3010 or if the program has exited. */
3012 if (!stop_stack_dummy)
3014 select_frame (get_current_frame ());
3016 /* Print current location without a level number, if
3017 we have changed functions or hit a breakpoint.
3018 Print source line if we have one.
3019 bpstat_print() contains the logic deciding in detail
3020 what to print, based on the event(s) that just occurred. */
3022 if (stop_print_frame && deprecated_selected_frame)
3026 int do_frame_printing = 1;
3028 bpstat_ret = bpstat_print (stop_bpstat);
3032 /* FIXME: cagney/2002-12-01: Given that a frame ID does
3033 (or should) carry around the function and does (or
3034 should) use that when doing a frame comparison. */
3036 && frame_id_eq (step_frame_id,
3037 get_frame_id (get_current_frame ()))
3038 && step_start_function == find_pc_function (stop_pc))
3039 source_flag = SRC_LINE; /* finished step, just print source line */
3041 source_flag = SRC_AND_LOC; /* print location and source line */
3043 case PRINT_SRC_AND_LOC:
3044 source_flag = SRC_AND_LOC; /* print location and source line */
3046 case PRINT_SRC_ONLY:
3047 source_flag = SRC_LINE;
3050 source_flag = SRC_LINE; /* something bogus */
3051 do_frame_printing = 0;
3054 internal_error (__FILE__, __LINE__, "Unknown value.");
3056 /* For mi, have the same behavior every time we stop:
3057 print everything but the source line. */
3058 if (ui_out_is_mi_like_p (uiout))
3059 source_flag = LOC_AND_ADDRESS;
3061 if (ui_out_is_mi_like_p (uiout))
3062 ui_out_field_int (uiout, "thread-id",
3063 pid_to_thread_id (inferior_ptid));
3064 /* The behavior of this routine with respect to the source
3066 SRC_LINE: Print only source line
3067 LOCATION: Print only location
3068 SRC_AND_LOC: Print location and source line */
3069 if (do_frame_printing)
3070 print_stack_frame (deprecated_selected_frame, -1, source_flag);
3072 /* Display the auto-display expressions. */
3077 /* Save the function value return registers, if we care.
3078 We might be about to restore their previous contents. */
3079 if (proceed_to_finish)
3080 /* NB: The copy goes through to the target picking up the value of
3081 all the registers. */
3082 regcache_cpy (stop_registers, current_regcache);
3084 if (stop_stack_dummy)
3086 /* Pop the empty frame that contains the stack dummy. POP_FRAME
3087 ends with a setting of the current frame, so we can use that
3089 frame_pop (get_current_frame ());
3090 /* Set stop_pc to what it was before we called the function.
3091 Can't rely on restore_inferior_status because that only gets
3092 called if we don't stop in the called function. */
3093 stop_pc = read_pc ();
3094 select_frame (get_current_frame ());
3098 annotate_stopped ();
3099 observer_notify_normal_stop ();
3103 hook_stop_stub (void *cmd)
3105 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
3110 signal_stop_state (int signo)
3112 return signal_stop[signo];
3116 signal_print_state (int signo)
3118 return signal_print[signo];
3122 signal_pass_state (int signo)
3124 return signal_program[signo];
3128 signal_stop_update (int signo, int state)
3130 int ret = signal_stop[signo];
3131 signal_stop[signo] = state;
3136 signal_print_update (int signo, int state)
3138 int ret = signal_print[signo];
3139 signal_print[signo] = state;
3144 signal_pass_update (int signo, int state)
3146 int ret = signal_program[signo];
3147 signal_program[signo] = state;
3152 sig_print_header (void)
3155 Signal Stop\tPrint\tPass to program\tDescription\n");
3159 sig_print_info (enum target_signal oursig)
3161 char *name = target_signal_to_name (oursig);
3162 int name_padding = 13 - strlen (name);
3164 if (name_padding <= 0)
3167 printf_filtered ("%s", name);
3168 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
3169 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
3170 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
3171 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
3172 printf_filtered ("%s\n", target_signal_to_string (oursig));
3175 /* Specify how various signals in the inferior should be handled. */
3178 handle_command (char *args, int from_tty)
3181 int digits, wordlen;
3182 int sigfirst, signum, siglast;
3183 enum target_signal oursig;
3186 unsigned char *sigs;
3187 struct cleanup *old_chain;
3191 error_no_arg ("signal to handle");
3194 /* Allocate and zero an array of flags for which signals to handle. */
3196 nsigs = (int) TARGET_SIGNAL_LAST;
3197 sigs = (unsigned char *) alloca (nsigs);
3198 memset (sigs, 0, nsigs);
3200 /* Break the command line up into args. */
3202 argv = buildargv (args);
3207 old_chain = make_cleanup_freeargv (argv);
3209 /* Walk through the args, looking for signal oursigs, signal names, and
3210 actions. Signal numbers and signal names may be interspersed with
3211 actions, with the actions being performed for all signals cumulatively
3212 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
3214 while (*argv != NULL)
3216 wordlen = strlen (*argv);
3217 for (digits = 0; isdigit ((*argv)[digits]); digits++)
3221 sigfirst = siglast = -1;
3223 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
3225 /* Apply action to all signals except those used by the
3226 debugger. Silently skip those. */
3229 siglast = nsigs - 1;
3231 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
3233 SET_SIGS (nsigs, sigs, signal_stop);
3234 SET_SIGS (nsigs, sigs, signal_print);
3236 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
3238 UNSET_SIGS (nsigs, sigs, signal_program);
3240 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
3242 SET_SIGS (nsigs, sigs, signal_print);
3244 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
3246 SET_SIGS (nsigs, sigs, signal_program);
3248 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
3250 UNSET_SIGS (nsigs, sigs, signal_stop);
3252 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
3254 SET_SIGS (nsigs, sigs, signal_program);
3256 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
3258 UNSET_SIGS (nsigs, sigs, signal_print);
3259 UNSET_SIGS (nsigs, sigs, signal_stop);
3261 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
3263 UNSET_SIGS (nsigs, sigs, signal_program);
3265 else if (digits > 0)
3267 /* It is numeric. The numeric signal refers to our own
3268 internal signal numbering from target.h, not to host/target
3269 signal number. This is a feature; users really should be
3270 using symbolic names anyway, and the common ones like
3271 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
3273 sigfirst = siglast = (int)
3274 target_signal_from_command (atoi (*argv));
3275 if ((*argv)[digits] == '-')
3278 target_signal_from_command (atoi ((*argv) + digits + 1));
3280 if (sigfirst > siglast)
3282 /* Bet he didn't figure we'd think of this case... */
3290 oursig = target_signal_from_name (*argv);
3291 if (oursig != TARGET_SIGNAL_UNKNOWN)
3293 sigfirst = siglast = (int) oursig;
3297 /* Not a number and not a recognized flag word => complain. */
3298 error ("Unrecognized or ambiguous flag word: \"%s\".", *argv);
3302 /* If any signal numbers or symbol names were found, set flags for
3303 which signals to apply actions to. */
3305 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
3307 switch ((enum target_signal) signum)
3309 case TARGET_SIGNAL_TRAP:
3310 case TARGET_SIGNAL_INT:
3311 if (!allsigs && !sigs[signum])
3313 if (query ("%s is used by the debugger.\n\
3314 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal) signum)))
3320 printf_unfiltered ("Not confirmed, unchanged.\n");
3321 gdb_flush (gdb_stdout);
3325 case TARGET_SIGNAL_0:
3326 case TARGET_SIGNAL_DEFAULT:
3327 case TARGET_SIGNAL_UNKNOWN:
3328 /* Make sure that "all" doesn't print these. */
3339 target_notice_signals (inferior_ptid);
3343 /* Show the results. */
3344 sig_print_header ();
3345 for (signum = 0; signum < nsigs; signum++)
3349 sig_print_info (signum);
3354 do_cleanups (old_chain);
3358 xdb_handle_command (char *args, int from_tty)
3361 struct cleanup *old_chain;
3363 /* Break the command line up into args. */
3365 argv = buildargv (args);
3370 old_chain = make_cleanup_freeargv (argv);
3371 if (argv[1] != (char *) NULL)
3376 bufLen = strlen (argv[0]) + 20;
3377 argBuf = (char *) xmalloc (bufLen);
3381 enum target_signal oursig;
3383 oursig = target_signal_from_name (argv[0]);
3384 memset (argBuf, 0, bufLen);
3385 if (strcmp (argv[1], "Q") == 0)
3386 sprintf (argBuf, "%s %s", argv[0], "noprint");
3389 if (strcmp (argv[1], "s") == 0)
3391 if (!signal_stop[oursig])
3392 sprintf (argBuf, "%s %s", argv[0], "stop");
3394 sprintf (argBuf, "%s %s", argv[0], "nostop");
3396 else if (strcmp (argv[1], "i") == 0)
3398 if (!signal_program[oursig])
3399 sprintf (argBuf, "%s %s", argv[0], "pass");
3401 sprintf (argBuf, "%s %s", argv[0], "nopass");
3403 else if (strcmp (argv[1], "r") == 0)
3405 if (!signal_print[oursig])
3406 sprintf (argBuf, "%s %s", argv[0], "print");
3408 sprintf (argBuf, "%s %s", argv[0], "noprint");
3414 handle_command (argBuf, from_tty);
3416 printf_filtered ("Invalid signal handling flag.\n");
3421 do_cleanups (old_chain);
3424 /* Print current contents of the tables set by the handle command.
3425 It is possible we should just be printing signals actually used
3426 by the current target (but for things to work right when switching
3427 targets, all signals should be in the signal tables). */
3430 signals_info (char *signum_exp, int from_tty)
3432 enum target_signal oursig;
3433 sig_print_header ();
3437 /* First see if this is a symbol name. */
3438 oursig = target_signal_from_name (signum_exp);
3439 if (oursig == TARGET_SIGNAL_UNKNOWN)
3441 /* No, try numeric. */
3443 target_signal_from_command (parse_and_eval_long (signum_exp));
3445 sig_print_info (oursig);
3449 printf_filtered ("\n");
3450 /* These ugly casts brought to you by the native VAX compiler. */
3451 for (oursig = TARGET_SIGNAL_FIRST;
3452 (int) oursig < (int) TARGET_SIGNAL_LAST;
3453 oursig = (enum target_signal) ((int) oursig + 1))
3457 if (oursig != TARGET_SIGNAL_UNKNOWN
3458 && oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0)
3459 sig_print_info (oursig);
3462 printf_filtered ("\nUse the \"handle\" command to change these tables.\n");
3465 struct inferior_status
3467 enum target_signal stop_signal;
3471 int stop_stack_dummy;
3472 int stopped_by_random_signal;
3474 CORE_ADDR step_range_start;
3475 CORE_ADDR step_range_end;
3476 struct frame_id step_frame_id;
3477 enum step_over_calls_kind step_over_calls;
3478 CORE_ADDR step_resume_break_address;
3479 int stop_after_trap;
3480 int stop_soon_quietly;
3481 struct regcache *stop_registers;
3483 /* These are here because if call_function_by_hand has written some
3484 registers and then decides to call error(), we better not have changed
3486 struct regcache *registers;
3488 /* A frame unique identifier. */
3489 struct frame_id selected_frame_id;
3491 int breakpoint_proceeded;
3492 int restore_stack_info;
3493 int proceed_to_finish;
3497 write_inferior_status_register (struct inferior_status *inf_status, int regno,
3500 int size = REGISTER_RAW_SIZE (regno);
3501 void *buf = alloca (size);
3502 store_signed_integer (buf, size, val);
3503 regcache_raw_write (inf_status->registers, regno, buf);
3506 /* Save all of the information associated with the inferior<==>gdb
3507 connection. INF_STATUS is a pointer to a "struct inferior_status"
3508 (defined in inferior.h). */
3510 struct inferior_status *
3511 save_inferior_status (int restore_stack_info)
3513 struct inferior_status *inf_status = XMALLOC (struct inferior_status);
3515 inf_status->stop_signal = stop_signal;
3516 inf_status->stop_pc = stop_pc;
3517 inf_status->stop_step = stop_step;
3518 inf_status->stop_stack_dummy = stop_stack_dummy;
3519 inf_status->stopped_by_random_signal = stopped_by_random_signal;
3520 inf_status->trap_expected = trap_expected;
3521 inf_status->step_range_start = step_range_start;
3522 inf_status->step_range_end = step_range_end;
3523 inf_status->step_frame_id = step_frame_id;
3524 inf_status->step_over_calls = step_over_calls;
3525 inf_status->stop_after_trap = stop_after_trap;
3526 inf_status->stop_soon_quietly = stop_soon_quietly;
3527 /* Save original bpstat chain here; replace it with copy of chain.
3528 If caller's caller is walking the chain, they'll be happier if we
3529 hand them back the original chain when restore_inferior_status is
3531 inf_status->stop_bpstat = stop_bpstat;
3532 stop_bpstat = bpstat_copy (stop_bpstat);
3533 inf_status->breakpoint_proceeded = breakpoint_proceeded;
3534 inf_status->restore_stack_info = restore_stack_info;
3535 inf_status->proceed_to_finish = proceed_to_finish;
3537 inf_status->stop_registers = regcache_dup_no_passthrough (stop_registers);
3539 inf_status->registers = regcache_dup (current_regcache);
3541 inf_status->selected_frame_id = get_frame_id (deprecated_selected_frame);
3546 restore_selected_frame (void *args)
3548 struct frame_id *fid = (struct frame_id *) args;
3549 struct frame_info *frame;
3551 frame = frame_find_by_id (*fid);
3553 /* If inf_status->selected_frame_id is NULL, there was no previously
3557 warning ("Unable to restore previously selected frame.\n");
3561 select_frame (frame);
3567 restore_inferior_status (struct inferior_status *inf_status)
3569 stop_signal = inf_status->stop_signal;
3570 stop_pc = inf_status->stop_pc;
3571 stop_step = inf_status->stop_step;
3572 stop_stack_dummy = inf_status->stop_stack_dummy;
3573 stopped_by_random_signal = inf_status->stopped_by_random_signal;
3574 trap_expected = inf_status->trap_expected;
3575 step_range_start = inf_status->step_range_start;
3576 step_range_end = inf_status->step_range_end;
3577 step_frame_id = inf_status->step_frame_id;
3578 step_over_calls = inf_status->step_over_calls;
3579 stop_after_trap = inf_status->stop_after_trap;
3580 stop_soon_quietly = inf_status->stop_soon_quietly;
3581 bpstat_clear (&stop_bpstat);
3582 stop_bpstat = inf_status->stop_bpstat;
3583 breakpoint_proceeded = inf_status->breakpoint_proceeded;
3584 proceed_to_finish = inf_status->proceed_to_finish;
3586 /* FIXME: Is the restore of stop_registers always needed. */
3587 regcache_xfree (stop_registers);
3588 stop_registers = inf_status->stop_registers;
3590 /* The inferior can be gone if the user types "print exit(0)"
3591 (and perhaps other times). */
3592 if (target_has_execution)
3593 /* NB: The register write goes through to the target. */
3594 regcache_cpy (current_regcache, inf_status->registers);
3595 regcache_xfree (inf_status->registers);
3597 /* FIXME: If we are being called after stopping in a function which
3598 is called from gdb, we should not be trying to restore the
3599 selected frame; it just prints a spurious error message (The
3600 message is useful, however, in detecting bugs in gdb (like if gdb
3601 clobbers the stack)). In fact, should we be restoring the
3602 inferior status at all in that case? . */
3604 if (target_has_stack && inf_status->restore_stack_info)
3606 /* The point of catch_errors is that if the stack is clobbered,
3607 walking the stack might encounter a garbage pointer and
3608 error() trying to dereference it. */
3610 (restore_selected_frame, &inf_status->selected_frame_id,
3611 "Unable to restore previously selected frame:\n",
3612 RETURN_MASK_ERROR) == 0)
3613 /* Error in restoring the selected frame. Select the innermost
3615 select_frame (get_current_frame ());
3623 do_restore_inferior_status_cleanup (void *sts)
3625 restore_inferior_status (sts);
3629 make_cleanup_restore_inferior_status (struct inferior_status *inf_status)
3631 return make_cleanup (do_restore_inferior_status_cleanup, inf_status);
3635 discard_inferior_status (struct inferior_status *inf_status)
3637 /* See save_inferior_status for info on stop_bpstat. */
3638 bpstat_clear (&inf_status->stop_bpstat);
3639 regcache_xfree (inf_status->registers);
3640 regcache_xfree (inf_status->stop_registers);
3645 inferior_has_forked (int pid, int *child_pid)
3647 struct target_waitstatus last;
3650 get_last_target_status (&last_ptid, &last);
3652 if (last.kind != TARGET_WAITKIND_FORKED)
3655 if (ptid_get_pid (last_ptid) != pid)
3658 *child_pid = last.value.related_pid;
3663 inferior_has_vforked (int pid, int *child_pid)
3665 struct target_waitstatus last;
3668 get_last_target_status (&last_ptid, &last);
3670 if (last.kind != TARGET_WAITKIND_VFORKED)
3673 if (ptid_get_pid (last_ptid) != pid)
3676 *child_pid = last.value.related_pid;
3681 inferior_has_execd (int pid, char **execd_pathname)
3683 struct target_waitstatus last;
3686 get_last_target_status (&last_ptid, &last);
3688 if (last.kind != TARGET_WAITKIND_EXECD)
3691 if (ptid_get_pid (last_ptid) != pid)
3694 *execd_pathname = xstrdup (last.value.execd_pathname);
3698 /* Oft used ptids */
3700 ptid_t minus_one_ptid;
3702 /* Create a ptid given the necessary PID, LWP, and TID components. */
3705 ptid_build (int pid, long lwp, long tid)
3715 /* Create a ptid from just a pid. */
3718 pid_to_ptid (int pid)
3720 return ptid_build (pid, 0, 0);
3723 /* Fetch the pid (process id) component from a ptid. */
3726 ptid_get_pid (ptid_t ptid)
3731 /* Fetch the lwp (lightweight process) component from a ptid. */
3734 ptid_get_lwp (ptid_t ptid)
3739 /* Fetch the tid (thread id) component from a ptid. */
3742 ptid_get_tid (ptid_t ptid)
3747 /* ptid_equal() is used to test equality of two ptids. */
3750 ptid_equal (ptid_t ptid1, ptid_t ptid2)
3752 return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp
3753 && ptid1.tid == ptid2.tid);
3756 /* restore_inferior_ptid() will be used by the cleanup machinery
3757 to restore the inferior_ptid value saved in a call to
3758 save_inferior_ptid(). */
3761 restore_inferior_ptid (void *arg)
3763 ptid_t *saved_ptid_ptr = arg;
3764 inferior_ptid = *saved_ptid_ptr;
3768 /* Save the value of inferior_ptid so that it may be restored by a
3769 later call to do_cleanups(). Returns the struct cleanup pointer
3770 needed for later doing the cleanup. */
3773 save_inferior_ptid (void)
3775 ptid_t *saved_ptid_ptr;
3777 saved_ptid_ptr = xmalloc (sizeof (ptid_t));
3778 *saved_ptid_ptr = inferior_ptid;
3779 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
3786 stop_registers = regcache_xmalloc (current_gdbarch);
3790 _initialize_infrun (void)
3793 register int numsigs;
3794 struct cmd_list_element *c;
3796 register_gdbarch_swap (&stop_registers, sizeof (stop_registers), NULL);
3797 register_gdbarch_swap (NULL, 0, build_infrun);
3799 add_info ("signals", signals_info,
3800 "What debugger does when program gets various signals.\n\
3801 Specify a signal as argument to print info on that signal only.");
3802 add_info_alias ("handle", "signals", 0);
3804 add_com ("handle", class_run, handle_command,
3805 concat ("Specify how to handle a signal.\n\
3806 Args are signals and actions to apply to those signals.\n\
3807 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
3808 from 1-15 are allowed for compatibility with old versions of GDB.\n\
3809 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
3810 The special arg \"all\" is recognized to mean all signals except those\n\
3811 used by the debugger, typically SIGTRAP and SIGINT.\n", "Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
3812 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
3813 Stop means reenter debugger if this signal happens (implies print).\n\
3814 Print means print a message if this signal happens.\n\
3815 Pass means let program see this signal; otherwise program doesn't know.\n\
3816 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
3817 Pass and Stop may be combined.", NULL));
3820 add_com ("lz", class_info, signals_info,
3821 "What debugger does when program gets various signals.\n\
3822 Specify a signal as argument to print info on that signal only.");
3823 add_com ("z", class_run, xdb_handle_command,
3824 concat ("Specify how to handle a signal.\n\
3825 Args are signals and actions to apply to those signals.\n\
3826 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
3827 from 1-15 are allowed for compatibility with old versions of GDB.\n\
3828 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
3829 The special arg \"all\" is recognized to mean all signals except those\n\
3830 used by the debugger, typically SIGTRAP and SIGINT.\n", "Recognized actions include \"s\" (toggles between stop and nostop), \n\
3831 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
3832 nopass), \"Q\" (noprint)\n\
3833 Stop means reenter debugger if this signal happens (implies print).\n\
3834 Print means print a message if this signal happens.\n\
3835 Pass means let program see this signal; otherwise program doesn't know.\n\
3836 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
3837 Pass and Stop may be combined.", NULL));
3842 add_cmd ("stop", class_obscure, not_just_help_class_command, "There is no `stop' command, but you can set a hook on `stop'.\n\
3843 This allows you to set a list of commands to be run each time execution\n\
3844 of the program stops.", &cmdlist);
3846 numsigs = (int) TARGET_SIGNAL_LAST;
3847 signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
3848 signal_print = (unsigned char *)
3849 xmalloc (sizeof (signal_print[0]) * numsigs);
3850 signal_program = (unsigned char *)
3851 xmalloc (sizeof (signal_program[0]) * numsigs);
3852 for (i = 0; i < numsigs; i++)
3855 signal_print[i] = 1;
3856 signal_program[i] = 1;
3859 /* Signals caused by debugger's own actions
3860 should not be given to the program afterwards. */
3861 signal_program[TARGET_SIGNAL_TRAP] = 0;
3862 signal_program[TARGET_SIGNAL_INT] = 0;
3864 /* Signals that are not errors should not normally enter the debugger. */
3865 signal_stop[TARGET_SIGNAL_ALRM] = 0;
3866 signal_print[TARGET_SIGNAL_ALRM] = 0;
3867 signal_stop[TARGET_SIGNAL_VTALRM] = 0;
3868 signal_print[TARGET_SIGNAL_VTALRM] = 0;
3869 signal_stop[TARGET_SIGNAL_PROF] = 0;
3870 signal_print[TARGET_SIGNAL_PROF] = 0;
3871 signal_stop[TARGET_SIGNAL_CHLD] = 0;
3872 signal_print[TARGET_SIGNAL_CHLD] = 0;
3873 signal_stop[TARGET_SIGNAL_IO] = 0;
3874 signal_print[TARGET_SIGNAL_IO] = 0;
3875 signal_stop[TARGET_SIGNAL_POLL] = 0;
3876 signal_print[TARGET_SIGNAL_POLL] = 0;
3877 signal_stop[TARGET_SIGNAL_URG] = 0;
3878 signal_print[TARGET_SIGNAL_URG] = 0;
3879 signal_stop[TARGET_SIGNAL_WINCH] = 0;
3880 signal_print[TARGET_SIGNAL_WINCH] = 0;
3882 /* These signals are used internally by user-level thread
3883 implementations. (See signal(5) on Solaris.) Like the above
3884 signals, a healthy program receives and handles them as part of
3885 its normal operation. */
3886 signal_stop[TARGET_SIGNAL_LWP] = 0;
3887 signal_print[TARGET_SIGNAL_LWP] = 0;
3888 signal_stop[TARGET_SIGNAL_WAITING] = 0;
3889 signal_print[TARGET_SIGNAL_WAITING] = 0;
3890 signal_stop[TARGET_SIGNAL_CANCEL] = 0;
3891 signal_print[TARGET_SIGNAL_CANCEL] = 0;
3895 (add_set_cmd ("stop-on-solib-events", class_support, var_zinteger,
3896 (char *) &stop_on_solib_events,
3897 "Set stopping for shared library events.\n\
3898 If nonzero, gdb will give control to the user when the dynamic linker\n\
3899 notifies gdb of shared library events. The most common event of interest\n\
3900 to the user would be loading/unloading of a new library.\n", &setlist), &showlist);
3903 c = add_set_enum_cmd ("follow-fork-mode",
3905 follow_fork_mode_kind_names, &follow_fork_mode_string,
3906 /* ??rehrauer: The "both" option is broken, by what may be a 10.20
3907 kernel problem. It's also not terribly useful without a GUI to
3908 help the user drive two debuggers. So for now, I'm disabling
3909 the "both" option. */
3910 /* "Set debugger response to a program call of fork \
3912 A fork or vfork creates a new process. follow-fork-mode can be:\n\
3913 parent - the original process is debugged after a fork\n\
3914 child - the new process is debugged after a fork\n\
3915 both - both the parent and child are debugged after a fork\n\
3916 ask - the debugger will ask for one of the above choices\n\
3917 For \"both\", another copy of the debugger will be started to follow\n\
3918 the new child process. The original debugger will continue to follow\n\
3919 the original parent process. To distinguish their prompts, the\n\
3920 debugger copy's prompt will be changed.\n\
3921 For \"parent\" or \"child\", the unfollowed process will run free.\n\
3922 By default, the debugger will follow the parent process.",
3924 "Set debugger response to a program call of fork \
3926 A fork or vfork creates a new process. follow-fork-mode can be:\n\
3927 parent - the original process is debugged after a fork\n\
3928 child - the new process is debugged after a fork\n\
3929 ask - the debugger will ask for one of the above choices\n\
3930 For \"parent\" or \"child\", the unfollowed process will run free.\n\
3931 By default, the debugger will follow the parent process.", &setlist);
3932 add_show_from_set (c, &showlist);
3934 c = add_set_enum_cmd ("scheduler-locking", class_run, scheduler_enums, /* array of string names */
3935 &scheduler_mode, /* current mode */
3936 "Set mode for locking scheduler during execution.\n\
3937 off == no locking (threads may preempt at any time)\n\
3938 on == full locking (no thread except the current thread may run)\n\
3939 step == scheduler locked during every single-step operation.\n\
3940 In this mode, no other thread may run during a step command.\n\
3941 Other threads may run while stepping over a function call ('next').", &setlist);
3943 set_cmd_sfunc (c, set_schedlock_func); /* traps on target vector */
3944 add_show_from_set (c, &showlist);
3946 c = add_set_cmd ("step-mode", class_run,
3947 var_boolean, (char *) &step_stop_if_no_debug,
3948 "Set mode of the step operation. When set, doing a step over a\n\
3949 function without debug line information will stop at the first\n\
3950 instruction of that function. Otherwise, the function is skipped and\n\
3951 the step command stops at a different source line.", &setlist);
3952 add_show_from_set (c, &showlist);
3954 /* ptid initializations */
3955 null_ptid = ptid_build (0, 0, 0);
3956 minus_one_ptid = ptid_build (-1, 0, 0);
3957 inferior_ptid = null_ptid;
3958 target_last_wait_ptid = minus_one_ptid;