1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
5 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002 Free Software
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 59 Temple Place - Suite 330,
23 Boston, MA 02111-1307, USA. */
26 #include "gdb_string.h"
31 #include "breakpoint.h"
35 #include "cli/cli-script.h"
37 #include "gdbthread.h"
46 /* Prototypes for local functions */
48 static void signals_info (char *, int);
50 static void handle_command (char *, int);
52 static void sig_print_info (enum target_signal);
54 static void sig_print_header (void);
56 static void resume_cleanups (void *);
58 static int hook_stop_stub (void *);
60 static void delete_breakpoint_current_contents (void *);
62 static void set_follow_fork_mode_command (char *arg, int from_tty,
63 struct cmd_list_element *c);
65 static int restore_selected_frame (void *);
67 static void build_infrun (void);
69 static int follow_fork ();
71 static void set_schedlock_func (char *args, int from_tty,
72 struct cmd_list_element *c);
74 struct execution_control_state;
76 static int currently_stepping (struct execution_control_state *ecs);
78 static void xdb_handle_command (char *args, int from_tty);
80 void _initialize_infrun (void);
82 int inferior_ignoring_startup_exec_events = 0;
83 int inferior_ignoring_leading_exec_events = 0;
85 /* When set, stop the 'step' command if we enter a function which has
86 no line number information. The normal behavior is that we step
87 over such function. */
88 int step_stop_if_no_debug = 0;
90 /* In asynchronous mode, but simulating synchronous execution. */
92 int sync_execution = 0;
94 /* wait_for_inferior and normal_stop use this to notify the user
95 when the inferior stopped in a different thread than it had been
98 static ptid_t previous_inferior_ptid;
100 /* This is true for configurations that may follow through execl() and
101 similar functions. At present this is only true for HP-UX native. */
103 #ifndef MAY_FOLLOW_EXEC
104 #define MAY_FOLLOW_EXEC (0)
107 static int may_follow_exec = MAY_FOLLOW_EXEC;
109 /* Dynamic function trampolines are similar to solib trampolines in that they
110 are between the caller and the callee. The difference is that when you
111 enter a dynamic trampoline, you can't determine the callee's address. Some
112 (usually complex) code needs to run in the dynamic trampoline to figure out
113 the callee's address. This macro is usually called twice. First, when we
114 enter the trampoline (looks like a normal function call at that point). It
115 should return the PC of a point within the trampoline where the callee's
116 address is known. Second, when we hit the breakpoint, this routine returns
117 the callee's address. At that point, things proceed as per a step resume
120 #ifndef DYNAMIC_TRAMPOLINE_NEXTPC
121 #define DYNAMIC_TRAMPOLINE_NEXTPC(pc) 0
124 /* If the program uses ELF-style shared libraries, then calls to
125 functions in shared libraries go through stubs, which live in a
126 table called the PLT (Procedure Linkage Table). The first time the
127 function is called, the stub sends control to the dynamic linker,
128 which looks up the function's real address, patches the stub so
129 that future calls will go directly to the function, and then passes
130 control to the function.
132 If we are stepping at the source level, we don't want to see any of
133 this --- we just want to skip over the stub and the dynamic linker.
134 The simple approach is to single-step until control leaves the
137 However, on some systems (e.g., Red Hat's 5.2 distribution) the
138 dynamic linker calls functions in the shared C library, so you
139 can't tell from the PC alone whether the dynamic linker is still
140 running. In this case, we use a step-resume breakpoint to get us
141 past the dynamic linker, as if we were using "next" to step over a
144 IN_SOLIB_DYNSYM_RESOLVE_CODE says whether we're in the dynamic
145 linker code or not. Normally, this means we single-step. However,
146 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
147 address where we can place a step-resume breakpoint to get past the
148 linker's symbol resolution function.
150 IN_SOLIB_DYNSYM_RESOLVE_CODE can generally be implemented in a
151 pretty portable way, by comparing the PC against the address ranges
152 of the dynamic linker's sections.
154 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
155 it depends on internal details of the dynamic linker. It's usually
156 not too hard to figure out where to put a breakpoint, but it
157 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
158 sanity checking. If it can't figure things out, returning zero and
159 getting the (possibly confusing) stepping behavior is better than
160 signalling an error, which will obscure the change in the
163 #ifndef IN_SOLIB_DYNSYM_RESOLVE_CODE
164 #define IN_SOLIB_DYNSYM_RESOLVE_CODE(pc) 0
167 #ifndef SKIP_SOLIB_RESOLVER
168 #define SKIP_SOLIB_RESOLVER(pc) 0
171 /* This function returns TRUE if pc is the address of an instruction
172 that lies within the dynamic linker (such as the event hook, or the
175 This function must be used only when a dynamic linker event has
176 been caught, and the inferior is being stepped out of the hook, or
177 undefined results are guaranteed. */
179 #ifndef SOLIB_IN_DYNAMIC_LINKER
180 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
183 /* On MIPS16, a function that returns a floating point value may call
184 a library helper function to copy the return value to a floating point
185 register. The IGNORE_HELPER_CALL macro returns non-zero if we
186 should ignore (i.e. step over) this function call. */
187 #ifndef IGNORE_HELPER_CALL
188 #define IGNORE_HELPER_CALL(pc) 0
191 /* On some systems, the PC may be left pointing at an instruction that won't
192 actually be executed. This is usually indicated by a bit in the PSW. If
193 we find ourselves in such a state, then we step the target beyond the
194 nullified instruction before returning control to the user so as to avoid
197 #ifndef INSTRUCTION_NULLIFIED
198 #define INSTRUCTION_NULLIFIED 0
201 /* We can't step off a permanent breakpoint in the ordinary way, because we
202 can't remove it. Instead, we have to advance the PC to the next
203 instruction. This macro should expand to a pointer to a function that
204 does that, or zero if we have no such function. If we don't have a
205 definition for it, we have to report an error. */
206 #ifndef SKIP_PERMANENT_BREAKPOINT
207 #define SKIP_PERMANENT_BREAKPOINT (default_skip_permanent_breakpoint)
209 default_skip_permanent_breakpoint (void)
212 The program is stopped at a permanent breakpoint, but GDB does not know\n\
213 how to step past a permanent breakpoint on this architecture. Try using\n\
214 a command like `return' or `jump' to continue execution.");
219 /* Convert the #defines into values. This is temporary until wfi control
220 flow is completely sorted out. */
222 #ifndef HAVE_STEPPABLE_WATCHPOINT
223 #define HAVE_STEPPABLE_WATCHPOINT 0
225 #undef HAVE_STEPPABLE_WATCHPOINT
226 #define HAVE_STEPPABLE_WATCHPOINT 1
229 #ifndef HAVE_CONTINUABLE_WATCHPOINT
230 #define HAVE_CONTINUABLE_WATCHPOINT 0
232 #undef HAVE_CONTINUABLE_WATCHPOINT
233 #define HAVE_CONTINUABLE_WATCHPOINT 1
236 #ifndef CANNOT_STEP_HW_WATCHPOINTS
237 #define CANNOT_STEP_HW_WATCHPOINTS 0
239 #undef CANNOT_STEP_HW_WATCHPOINTS
240 #define CANNOT_STEP_HW_WATCHPOINTS 1
243 /* Tables of how to react to signals; the user sets them. */
245 static unsigned char *signal_stop;
246 static unsigned char *signal_print;
247 static unsigned char *signal_program;
249 #define SET_SIGS(nsigs,sigs,flags) \
251 int signum = (nsigs); \
252 while (signum-- > 0) \
253 if ((sigs)[signum]) \
254 (flags)[signum] = 1; \
257 #define UNSET_SIGS(nsigs,sigs,flags) \
259 int signum = (nsigs); \
260 while (signum-- > 0) \
261 if ((sigs)[signum]) \
262 (flags)[signum] = 0; \
265 /* Value to pass to target_resume() to cause all threads to resume */
267 #define RESUME_ALL (pid_to_ptid (-1))
269 /* Command list pointer for the "stop" placeholder. */
271 static struct cmd_list_element *stop_command;
273 /* Nonzero if breakpoints are now inserted in the inferior. */
275 static int breakpoints_inserted;
277 /* Function inferior was in as of last step command. */
279 static struct symbol *step_start_function;
281 /* Nonzero if we are expecting a trace trap and should proceed from it. */
283 static int trap_expected;
286 /* Nonzero if we want to give control to the user when we're notified
287 of shared library events by the dynamic linker. */
288 static int stop_on_solib_events;
292 /* Nonzero if the next time we try to continue the inferior, it will
293 step one instruction and generate a spurious trace trap.
294 This is used to compensate for a bug in HP-UX. */
296 static int trap_expected_after_continue;
299 /* Nonzero means expecting a trace trap
300 and should stop the inferior and return silently when it happens. */
304 /* Nonzero means expecting a trap and caller will handle it themselves.
305 It is used after attach, due to attaching to a process;
306 when running in the shell before the child program has been exec'd;
307 and when running some kinds of remote stuff (FIXME?). */
309 int stop_soon_quietly;
311 /* Nonzero if proceed is being used for a "finish" command or a similar
312 situation when stop_registers should be saved. */
314 int proceed_to_finish;
316 /* Save register contents here when about to pop a stack dummy frame,
317 if-and-only-if proceed_to_finish is set.
318 Thus this contains the return value from the called function (assuming
319 values are returned in a register). */
321 struct regcache *stop_registers;
323 /* Nonzero if program stopped due to error trying to insert breakpoints. */
325 static int breakpoints_failed;
327 /* Nonzero after stop if current stack frame should be printed. */
329 static int stop_print_frame;
331 static struct breakpoint *step_resume_breakpoint = NULL;
332 static struct breakpoint *through_sigtramp_breakpoint = NULL;
334 /* On some platforms (e.g., HP-UX), hardware watchpoints have bad
335 interactions with an inferior that is running a kernel function
336 (aka, a system call or "syscall"). wait_for_inferior therefore
337 may have a need to know when the inferior is in a syscall. This
338 is a count of the number of inferior threads which are known to
339 currently be running in a syscall. */
340 static int number_of_threads_in_syscalls;
342 /* This is a cached copy of the pid/waitstatus of the last event
343 returned by target_wait()/target_wait_hook(). This information is
344 returned by get_last_target_status(). */
345 static ptid_t target_last_wait_ptid;
346 static struct target_waitstatus target_last_waitstatus;
348 /* This is used to remember when a fork, vfork or exec event
349 was caught by a catchpoint, and thus the event is to be
350 followed at the next resume of the inferior, and not
354 enum target_waitkind kind;
361 char *execd_pathname;
365 static const char follow_fork_mode_ask[] = "ask";
366 static const char follow_fork_mode_child[] = "child";
367 static const char follow_fork_mode_parent[] = "parent";
369 static const char *follow_fork_mode_kind_names[] = {
370 follow_fork_mode_ask,
371 follow_fork_mode_child,
372 follow_fork_mode_parent,
376 static const char *follow_fork_mode_string = follow_fork_mode_parent;
382 const char *follow_mode = follow_fork_mode_string;
383 int follow_child = (follow_mode == follow_fork_mode_child);
385 /* Or, did the user not know, and want us to ask? */
386 if (follow_fork_mode_string == follow_fork_mode_ask)
388 internal_error (__FILE__, __LINE__,
389 "follow_inferior_fork: \"ask\" mode not implemented");
390 /* follow_mode = follow_fork_mode_...; */
393 return target_follow_fork (follow_child);
397 follow_inferior_reset_breakpoints (void)
399 /* Was there a step_resume breakpoint? (There was if the user
400 did a "next" at the fork() call.) If so, explicitly reset its
403 step_resumes are a form of bp that are made to be per-thread.
404 Since we created the step_resume bp when the parent process
405 was being debugged, and now are switching to the child process,
406 from the breakpoint package's viewpoint, that's a switch of
407 "threads". We must update the bp's notion of which thread
408 it is for, or it'll be ignored when it triggers. */
410 if (step_resume_breakpoint)
411 breakpoint_re_set_thread (step_resume_breakpoint);
413 /* Reinsert all breakpoints in the child. The user may have set
414 breakpoints after catching the fork, in which case those
415 were never set in the child, but only in the parent. This makes
416 sure the inserted breakpoints match the breakpoint list. */
418 breakpoint_re_set ();
419 insert_breakpoints ();
422 /* EXECD_PATHNAME is assumed to be non-NULL. */
425 follow_exec (int pid, char *execd_pathname)
428 struct target_ops *tgt;
430 if (!may_follow_exec)
433 /* This is an exec event that we actually wish to pay attention to.
434 Refresh our symbol table to the newly exec'd program, remove any
437 If there are breakpoints, they aren't really inserted now,
438 since the exec() transformed our inferior into a fresh set
441 We want to preserve symbolic breakpoints on the list, since
442 we have hopes that they can be reset after the new a.out's
443 symbol table is read.
445 However, any "raw" breakpoints must be removed from the list
446 (e.g., the solib bp's), since their address is probably invalid
449 And, we DON'T want to call delete_breakpoints() here, since
450 that may write the bp's "shadow contents" (the instruction
451 value that was overwritten witha TRAP instruction). Since
452 we now have a new a.out, those shadow contents aren't valid. */
453 update_breakpoints_after_exec ();
455 /* If there was one, it's gone now. We cannot truly step-to-next
456 statement through an exec(). */
457 step_resume_breakpoint = NULL;
458 step_range_start = 0;
461 /* If there was one, it's gone now. */
462 through_sigtramp_breakpoint = NULL;
464 /* What is this a.out's name? */
465 printf_unfiltered ("Executing new program: %s\n", execd_pathname);
467 /* We've followed the inferior through an exec. Therefore, the
468 inferior has essentially been killed & reborn. */
470 /* First collect the run target in effect. */
471 tgt = find_run_target ();
472 /* If we can't find one, things are in a very strange state... */
474 error ("Could find run target to save before following exec");
476 gdb_flush (gdb_stdout);
477 target_mourn_inferior ();
478 inferior_ptid = pid_to_ptid (saved_pid);
479 /* Because mourn_inferior resets inferior_ptid. */
482 /* That a.out is now the one to use. */
483 exec_file_attach (execd_pathname, 0);
485 /* And also is where symbols can be found. */
486 symbol_file_add_main (execd_pathname, 0);
488 /* Reset the shared library package. This ensures that we get
489 a shlib event when the child reaches "_start", at which point
490 the dld will have had a chance to initialize the child. */
491 #if defined(SOLIB_RESTART)
494 #ifdef SOLIB_CREATE_INFERIOR_HOOK
495 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
498 /* Reinsert all breakpoints. (Those which were symbolic have
499 been reset to the proper address in the new a.out, thanks
500 to symbol_file_command...) */
501 insert_breakpoints ();
503 /* The next resume of this inferior should bring it to the shlib
504 startup breakpoints. (If the user had also set bp's on
505 "main" from the old (parent) process, then they'll auto-
506 matically get reset there in the new process.) */
509 /* Non-zero if we just simulating a single-step. This is needed
510 because we cannot remove the breakpoints in the inferior process
511 until after the `wait' in `wait_for_inferior'. */
512 static int singlestep_breakpoints_inserted_p = 0;
515 /* Things to clean up if we QUIT out of resume (). */
518 resume_cleanups (void *ignore)
523 static const char schedlock_off[] = "off";
524 static const char schedlock_on[] = "on";
525 static const char schedlock_step[] = "step";
526 static const char *scheduler_mode = schedlock_off;
527 static const char *scheduler_enums[] = {
535 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
537 /* NOTE: cagney/2002-03-17: The add_show_from_set() function clones
538 the set command passed as a parameter. The clone operation will
539 include (BUG?) any ``set'' command callback, if present.
540 Commands like ``info set'' call all the ``show'' command
541 callbacks. Unfortunatly, for ``show'' commands cloned from
542 ``set'', this includes callbacks belonging to ``set'' commands.
543 Making this worse, this only occures if add_show_from_set() is
544 called after add_cmd_sfunc() (BUG?). */
545 if (cmd_type (c) == set_cmd)
546 if (!target_can_lock_scheduler)
548 scheduler_mode = schedlock_off;
549 error ("Target '%s' cannot support this command.", target_shortname);
554 /* Resume the inferior, but allow a QUIT. This is useful if the user
555 wants to interrupt some lengthy single-stepping operation
556 (for child processes, the SIGINT goes to the inferior, and so
557 we get a SIGINT random_signal, but for remote debugging and perhaps
558 other targets, that's not true).
560 STEP nonzero if we should step (zero to continue instead).
561 SIG is the signal to give the inferior (zero for none). */
563 resume (int step, enum target_signal sig)
565 int should_resume = 1;
566 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
569 /* FIXME: calling breakpoint_here_p (read_pc ()) three times! */
572 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
573 over an instruction that causes a page fault without triggering
574 a hardware watchpoint. The kernel properly notices that it shouldn't
575 stop, because the hardware watchpoint is not triggered, but it forgets
576 the step request and continues the program normally.
577 Work around the problem by removing hardware watchpoints if a step is
578 requested, GDB will check for a hardware watchpoint trigger after the
580 if (CANNOT_STEP_HW_WATCHPOINTS && step && breakpoints_inserted)
581 remove_hw_watchpoints ();
584 /* Normally, by the time we reach `resume', the breakpoints are either
585 removed or inserted, as appropriate. The exception is if we're sitting
586 at a permanent breakpoint; we need to step over it, but permanent
587 breakpoints can't be removed. So we have to test for it here. */
588 if (breakpoint_here_p (read_pc ()) == permanent_breakpoint_here)
589 SKIP_PERMANENT_BREAKPOINT ();
591 if (SOFTWARE_SINGLE_STEP_P () && step)
593 /* Do it the hard way, w/temp breakpoints */
594 SOFTWARE_SINGLE_STEP (sig, 1 /*insert-breakpoints */ );
595 /* ...and don't ask hardware to do it. */
597 /* and do not pull these breakpoints until after a `wait' in
598 `wait_for_inferior' */
599 singlestep_breakpoints_inserted_p = 1;
602 /* Handle any optimized stores to the inferior NOW... */
603 #ifdef DO_DEFERRED_STORES
607 /* If there were any forks/vforks/execs that were caught and are
608 now to be followed, then do so. */
609 switch (pending_follow.kind)
611 case TARGET_WAITKIND_FORKED:
612 case TARGET_WAITKIND_VFORKED:
613 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
618 case TARGET_WAITKIND_EXECD:
619 /* follow_exec is called as soon as the exec event is seen. */
620 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
627 /* Install inferior's terminal modes. */
628 target_terminal_inferior ();
634 resume_ptid = RESUME_ALL; /* Default */
636 if ((step || singlestep_breakpoints_inserted_p) &&
637 !breakpoints_inserted && breakpoint_here_p (read_pc ()))
639 /* Stepping past a breakpoint without inserting breakpoints.
640 Make sure only the current thread gets to step, so that
641 other threads don't sneak past breakpoints while they are
644 resume_ptid = inferior_ptid;
647 if ((scheduler_mode == schedlock_on) ||
648 (scheduler_mode == schedlock_step &&
649 (step || singlestep_breakpoints_inserted_p)))
651 /* User-settable 'scheduler' mode requires solo thread resume. */
652 resume_ptid = inferior_ptid;
655 if (CANNOT_STEP_BREAKPOINT)
657 /* Most targets can step a breakpoint instruction, thus
658 executing it normally. But if this one cannot, just
659 continue and we will hit it anyway. */
660 if (step && breakpoints_inserted && breakpoint_here_p (read_pc ()))
663 target_resume (resume_ptid, step, sig);
666 discard_cleanups (old_cleanups);
670 /* Clear out all variables saying what to do when inferior is continued.
671 First do this, then set the ones you want, then call `proceed'. */
674 clear_proceed_status (void)
677 step_range_start = 0;
679 step_frame_id = null_frame_id;
680 step_over_calls = STEP_OVER_UNDEBUGGABLE;
682 stop_soon_quietly = 0;
683 proceed_to_finish = 0;
684 breakpoint_proceeded = 1; /* We're about to proceed... */
686 /* Discard any remaining commands or status from previous stop. */
687 bpstat_clear (&stop_bpstat);
690 /* Basic routine for continuing the program in various fashions.
692 ADDR is the address to resume at, or -1 for resume where stopped.
693 SIGGNAL is the signal to give it, or 0 for none,
694 or -1 for act according to how it stopped.
695 STEP is nonzero if should trap after one instruction.
696 -1 means return after that and print nothing.
697 You should probably set various step_... variables
698 before calling here, if you are stepping.
700 You should call clear_proceed_status before calling proceed. */
703 proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
708 step_start_function = find_pc_function (read_pc ());
712 if (addr == (CORE_ADDR) -1)
714 /* If there is a breakpoint at the address we will resume at,
715 step one instruction before inserting breakpoints
716 so that we do not stop right away (and report a second
717 hit at this breakpoint). */
719 if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
722 #ifndef STEP_SKIPS_DELAY
723 #define STEP_SKIPS_DELAY(pc) (0)
724 #define STEP_SKIPS_DELAY_P (0)
726 /* Check breakpoint_here_p first, because breakpoint_here_p is fast
727 (it just checks internal GDB data structures) and STEP_SKIPS_DELAY
728 is slow (it needs to read memory from the target). */
729 if (STEP_SKIPS_DELAY_P
730 && breakpoint_here_p (read_pc () + 4)
731 && STEP_SKIPS_DELAY (read_pc ()))
739 #ifdef PREPARE_TO_PROCEED
740 /* In a multi-threaded task we may select another thread
741 and then continue or step.
743 But if the old thread was stopped at a breakpoint, it
744 will immediately cause another breakpoint stop without
745 any execution (i.e. it will report a breakpoint hit
746 incorrectly). So we must step over it first.
748 PREPARE_TO_PROCEED checks the current thread against the thread
749 that reported the most recent event. If a step-over is required
750 it returns TRUE and sets the current thread to the old thread. */
751 if (PREPARE_TO_PROCEED (1) && breakpoint_here_p (read_pc ()))
756 #endif /* PREPARE_TO_PROCEED */
759 if (trap_expected_after_continue)
761 /* If (step == 0), a trap will be automatically generated after
762 the first instruction is executed. Force step one
763 instruction to clear this condition. This should not occur
764 if step is nonzero, but it is harmless in that case. */
766 trap_expected_after_continue = 0;
768 #endif /* HP_OS_BUG */
771 /* We will get a trace trap after one instruction.
772 Continue it automatically and insert breakpoints then. */
776 insert_breakpoints ();
777 /* If we get here there was no call to error() in
778 insert breakpoints -- so they were inserted. */
779 breakpoints_inserted = 1;
782 if (siggnal != TARGET_SIGNAL_DEFAULT)
783 stop_signal = siggnal;
784 /* If this signal should not be seen by program,
785 give it zero. Used for debugging signals. */
786 else if (!signal_program[stop_signal])
787 stop_signal = TARGET_SIGNAL_0;
789 annotate_starting ();
791 /* Make sure that output from GDB appears before output from the
793 gdb_flush (gdb_stdout);
795 /* Resume inferior. */
796 resume (oneproc || step || bpstat_should_step (), stop_signal);
798 /* Wait for it to stop (if not standalone)
799 and in any case decode why it stopped, and act accordingly. */
800 /* Do this only if we are not using the event loop, or if the target
801 does not support asynchronous execution. */
802 if (!event_loop_p || !target_can_async_p ())
804 wait_for_inferior ();
809 /* Record the pc and sp of the program the last time it stopped.
810 These are just used internally by wait_for_inferior, but need
811 to be preserved over calls to it and cleared when the inferior
813 static CORE_ADDR prev_pc;
814 static CORE_ADDR prev_func_start;
815 static char *prev_func_name;
818 /* Start remote-debugging of a machine over a serial link. */
824 init_wait_for_inferior ();
825 stop_soon_quietly = 1;
828 /* Always go on waiting for the target, regardless of the mode. */
829 /* FIXME: cagney/1999-09-23: At present it isn't possible to
830 indicate to wait_for_inferior that a target should timeout if
831 nothing is returned (instead of just blocking). Because of this,
832 targets expecting an immediate response need to, internally, set
833 things up so that the target_wait() is forced to eventually
835 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
836 differentiate to its caller what the state of the target is after
837 the initial open has been performed. Here we're assuming that
838 the target has stopped. It should be possible to eventually have
839 target_open() return to the caller an indication that the target
840 is currently running and GDB state should be set to the same as
842 wait_for_inferior ();
846 /* Initialize static vars when a new inferior begins. */
849 init_wait_for_inferior (void)
851 /* These are meaningless until the first time through wait_for_inferior. */
854 prev_func_name = NULL;
857 trap_expected_after_continue = 0;
859 breakpoints_inserted = 0;
860 breakpoint_init_inferior (inf_starting);
862 /* Don't confuse first call to proceed(). */
863 stop_signal = TARGET_SIGNAL_0;
865 /* The first resume is not following a fork/vfork/exec. */
866 pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
868 /* See wait_for_inferior's handling of SYSCALL_ENTRY/RETURN events. */
869 number_of_threads_in_syscalls = 0;
871 clear_proceed_status ();
875 delete_breakpoint_current_contents (void *arg)
877 struct breakpoint **breakpointp = (struct breakpoint **) arg;
878 if (*breakpointp != NULL)
880 delete_breakpoint (*breakpointp);
885 /* This enum encodes possible reasons for doing a target_wait, so that
886 wfi can call target_wait in one place. (Ultimately the call will be
887 moved out of the infinite loop entirely.) */
891 infwait_normal_state,
892 infwait_thread_hop_state,
893 infwait_nullified_state,
894 infwait_nonstep_watch_state
897 /* Why did the inferior stop? Used to print the appropriate messages
898 to the interface from within handle_inferior_event(). */
899 enum inferior_stop_reason
901 /* We don't know why. */
903 /* Step, next, nexti, stepi finished. */
905 /* Found breakpoint. */
907 /* Inferior terminated by signal. */
909 /* Inferior exited. */
911 /* Inferior received signal, and user asked to be notified. */
915 /* This structure contains what used to be local variables in
916 wait_for_inferior. Probably many of them can return to being
917 locals in handle_inferior_event. */
919 struct execution_control_state
921 struct target_waitstatus ws;
922 struct target_waitstatus *wp;
925 CORE_ADDR stop_func_start;
926 CORE_ADDR stop_func_end;
927 char *stop_func_name;
928 struct symtab_and_line sal;
929 int remove_breakpoints_on_following_step;
931 struct symtab *current_symtab;
932 int handling_longjmp; /* FIXME */
934 ptid_t saved_inferior_ptid;
936 int stepping_through_solib_after_catch;
937 bpstat stepping_through_solib_catchpoints;
938 int enable_hw_watchpoints_after_wait;
939 int stepping_through_sigtramp;
940 int new_thread_event;
941 struct target_waitstatus tmpstatus;
942 enum infwait_states infwait_state;
947 void init_execution_control_state (struct execution_control_state *ecs);
949 void handle_inferior_event (struct execution_control_state *ecs);
951 static void check_sigtramp2 (struct execution_control_state *ecs);
952 static void step_into_function (struct execution_control_state *ecs);
953 static void step_over_function (struct execution_control_state *ecs);
954 static void stop_stepping (struct execution_control_state *ecs);
955 static void prepare_to_wait (struct execution_control_state *ecs);
956 static void keep_going (struct execution_control_state *ecs);
957 static void print_stop_reason (enum inferior_stop_reason stop_reason,
960 /* Wait for control to return from inferior to debugger.
961 If inferior gets a signal, we may decide to start it up again
962 instead of returning. That is why there is a loop in this function.
963 When this function actually returns it means the inferior
964 should be left stopped and GDB should read more commands. */
967 wait_for_inferior (void)
969 struct cleanup *old_cleanups;
970 struct execution_control_state ecss;
971 struct execution_control_state *ecs;
973 old_cleanups = make_cleanup (delete_step_resume_breakpoint,
974 &step_resume_breakpoint);
975 make_cleanup (delete_breakpoint_current_contents,
976 &through_sigtramp_breakpoint);
978 /* wfi still stays in a loop, so it's OK just to take the address of
979 a local to get the ecs pointer. */
982 /* Fill in with reasonable starting values. */
983 init_execution_control_state (ecs);
985 /* We'll update this if & when we switch to a new thread. */
986 previous_inferior_ptid = inferior_ptid;
988 overlay_cache_invalid = 1;
990 /* We have to invalidate the registers BEFORE calling target_wait
991 because they can be loaded from the target while in target_wait.
992 This makes remote debugging a bit more efficient for those
993 targets that provide critical registers as part of their normal
996 registers_changed ();
1000 if (target_wait_hook)
1001 ecs->ptid = target_wait_hook (ecs->waiton_ptid, ecs->wp);
1003 ecs->ptid = target_wait (ecs->waiton_ptid, ecs->wp);
1005 /* Now figure out what to do with the result of the result. */
1006 handle_inferior_event (ecs);
1008 if (!ecs->wait_some_more)
1011 do_cleanups (old_cleanups);
1014 /* Asynchronous version of wait_for_inferior. It is called by the
1015 event loop whenever a change of state is detected on the file
1016 descriptor corresponding to the target. It can be called more than
1017 once to complete a single execution command. In such cases we need
1018 to keep the state in a global variable ASYNC_ECSS. If it is the
1019 last time that this function is called for a single execution
1020 command, then report to the user that the inferior has stopped, and
1021 do the necessary cleanups. */
1023 struct execution_control_state async_ecss;
1024 struct execution_control_state *async_ecs;
1027 fetch_inferior_event (void *client_data)
1029 static struct cleanup *old_cleanups;
1031 async_ecs = &async_ecss;
1033 if (!async_ecs->wait_some_more)
1035 old_cleanups = make_exec_cleanup (delete_step_resume_breakpoint,
1036 &step_resume_breakpoint);
1037 make_exec_cleanup (delete_breakpoint_current_contents,
1038 &through_sigtramp_breakpoint);
1040 /* Fill in with reasonable starting values. */
1041 init_execution_control_state (async_ecs);
1043 /* We'll update this if & when we switch to a new thread. */
1044 previous_inferior_ptid = inferior_ptid;
1046 overlay_cache_invalid = 1;
1048 /* We have to invalidate the registers BEFORE calling target_wait
1049 because they can be loaded from the target while in target_wait.
1050 This makes remote debugging a bit more efficient for those
1051 targets that provide critical registers as part of their normal
1052 status mechanism. */
1054 registers_changed ();
1057 if (target_wait_hook)
1059 target_wait_hook (async_ecs->waiton_ptid, async_ecs->wp);
1061 async_ecs->ptid = target_wait (async_ecs->waiton_ptid, async_ecs->wp);
1063 /* Now figure out what to do with the result of the result. */
1064 handle_inferior_event (async_ecs);
1066 if (!async_ecs->wait_some_more)
1068 /* Do only the cleanups that have been added by this
1069 function. Let the continuations for the commands do the rest,
1070 if there are any. */
1071 do_exec_cleanups (old_cleanups);
1073 if (step_multi && stop_step)
1074 inferior_event_handler (INF_EXEC_CONTINUE, NULL);
1076 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
1080 /* Prepare an execution control state for looping through a
1081 wait_for_inferior-type loop. */
1084 init_execution_control_state (struct execution_control_state *ecs)
1086 /* ecs->another_trap? */
1087 ecs->random_signal = 0;
1088 ecs->remove_breakpoints_on_following_step = 0;
1089 ecs->handling_longjmp = 0; /* FIXME */
1090 ecs->update_step_sp = 0;
1091 ecs->stepping_through_solib_after_catch = 0;
1092 ecs->stepping_through_solib_catchpoints = NULL;
1093 ecs->enable_hw_watchpoints_after_wait = 0;
1094 ecs->stepping_through_sigtramp = 0;
1095 ecs->sal = find_pc_line (prev_pc, 0);
1096 ecs->current_line = ecs->sal.line;
1097 ecs->current_symtab = ecs->sal.symtab;
1098 ecs->infwait_state = infwait_normal_state;
1099 ecs->waiton_ptid = pid_to_ptid (-1);
1100 ecs->wp = &(ecs->ws);
1103 /* Call this function before setting step_resume_breakpoint, as a
1104 sanity check. There should never be more than one step-resume
1105 breakpoint per thread, so we should never be setting a new
1106 step_resume_breakpoint when one is already active. */
1108 check_for_old_step_resume_breakpoint (void)
1110 if (step_resume_breakpoint)
1112 ("GDB bug: infrun.c (wait_for_inferior): dropping old step_resume breakpoint");
1115 /* Return the cached copy of the last pid/waitstatus returned by
1116 target_wait()/target_wait_hook(). The data is actually cached by
1117 handle_inferior_event(), which gets called immediately after
1118 target_wait()/target_wait_hook(). */
1121 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
1123 *ptidp = target_last_wait_ptid;
1124 *status = target_last_waitstatus;
1127 /* Switch thread contexts, maintaining "infrun state". */
1130 context_switch (struct execution_control_state *ecs)
1132 /* Caution: it may happen that the new thread (or the old one!)
1133 is not in the thread list. In this case we must not attempt
1134 to "switch context", or we run the risk that our context may
1135 be lost. This may happen as a result of the target module
1136 mishandling thread creation. */
1138 if (in_thread_list (inferior_ptid) && in_thread_list (ecs->ptid))
1139 { /* Perform infrun state context switch: */
1140 /* Save infrun state for the old thread. */
1141 save_infrun_state (inferior_ptid, prev_pc,
1142 prev_func_start, prev_func_name,
1143 trap_expected, step_resume_breakpoint,
1144 through_sigtramp_breakpoint, step_range_start,
1145 step_range_end, &step_frame_id,
1146 ecs->handling_longjmp, ecs->another_trap,
1147 ecs->stepping_through_solib_after_catch,
1148 ecs->stepping_through_solib_catchpoints,
1149 ecs->stepping_through_sigtramp,
1150 ecs->current_line, ecs->current_symtab, step_sp);
1152 /* Load infrun state for the new thread. */
1153 load_infrun_state (ecs->ptid, &prev_pc,
1154 &prev_func_start, &prev_func_name,
1155 &trap_expected, &step_resume_breakpoint,
1156 &through_sigtramp_breakpoint, &step_range_start,
1157 &step_range_end, &step_frame_id,
1158 &ecs->handling_longjmp, &ecs->another_trap,
1159 &ecs->stepping_through_solib_after_catch,
1160 &ecs->stepping_through_solib_catchpoints,
1161 &ecs->stepping_through_sigtramp,
1162 &ecs->current_line, &ecs->current_symtab, &step_sp);
1164 inferior_ptid = ecs->ptid;
1168 /* Given an execution control state that has been freshly filled in
1169 by an event from the inferior, figure out what it means and take
1170 appropriate action. */
1173 handle_inferior_event (struct execution_control_state *ecs)
1176 int stepped_after_stopped_by_watchpoint;
1177 int sw_single_step_trap_p = 0;
1179 /* Cache the last pid/waitstatus. */
1180 target_last_wait_ptid = ecs->ptid;
1181 target_last_waitstatus = *ecs->wp;
1183 switch (ecs->infwait_state)
1185 case infwait_thread_hop_state:
1186 /* Cancel the waiton_ptid. */
1187 ecs->waiton_ptid = pid_to_ptid (-1);
1188 /* Fall thru to the normal_state case. */
1190 case infwait_normal_state:
1191 /* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
1192 is serviced in this loop, below. */
1193 if (ecs->enable_hw_watchpoints_after_wait)
1195 TARGET_ENABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
1196 ecs->enable_hw_watchpoints_after_wait = 0;
1198 stepped_after_stopped_by_watchpoint = 0;
1201 case infwait_nullified_state:
1204 case infwait_nonstep_watch_state:
1205 insert_breakpoints ();
1207 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1208 handle things like signals arriving and other things happening
1209 in combination correctly? */
1210 stepped_after_stopped_by_watchpoint = 1;
1213 ecs->infwait_state = infwait_normal_state;
1215 flush_cached_frames ();
1217 /* If it's a new process, add it to the thread database */
1219 ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
1220 && !in_thread_list (ecs->ptid));
1222 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
1223 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
1225 add_thread (ecs->ptid);
1227 ui_out_text (uiout, "[New ");
1228 ui_out_text (uiout, target_pid_or_tid_to_str (ecs->ptid));
1229 ui_out_text (uiout, "]\n");
1232 /* NOTE: This block is ONLY meant to be invoked in case of a
1233 "thread creation event"! If it is invoked for any other
1234 sort of event (such as a new thread landing on a breakpoint),
1235 the event will be discarded, which is almost certainly
1238 To avoid this, the low-level module (eg. target_wait)
1239 should call in_thread_list and add_thread, so that the
1240 new thread is known by the time we get here. */
1242 /* We may want to consider not doing a resume here in order
1243 to give the user a chance to play with the new thread.
1244 It might be good to make that a user-settable option. */
1246 /* At this point, all threads are stopped (happens
1247 automatically in either the OS or the native code).
1248 Therefore we need to continue all threads in order to
1251 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
1252 prepare_to_wait (ecs);
1257 switch (ecs->ws.kind)
1259 case TARGET_WAITKIND_LOADED:
1260 /* Ignore gracefully during startup of the inferior, as it
1261 might be the shell which has just loaded some objects,
1262 otherwise add the symbols for the newly loaded objects. */
1264 if (!stop_soon_quietly)
1266 /* Remove breakpoints, SOLIB_ADD might adjust
1267 breakpoint addresses via breakpoint_re_set. */
1268 if (breakpoints_inserted)
1269 remove_breakpoints ();
1271 /* Check for any newly added shared libraries if we're
1272 supposed to be adding them automatically. Switch
1273 terminal for any messages produced by
1274 breakpoint_re_set. */
1275 target_terminal_ours_for_output ();
1276 SOLIB_ADD (NULL, 0, NULL, auto_solib_add);
1277 target_terminal_inferior ();
1279 /* Reinsert breakpoints and continue. */
1280 if (breakpoints_inserted)
1281 insert_breakpoints ();
1284 resume (0, TARGET_SIGNAL_0);
1285 prepare_to_wait (ecs);
1288 case TARGET_WAITKIND_SPURIOUS:
1289 resume (0, TARGET_SIGNAL_0);
1290 prepare_to_wait (ecs);
1293 case TARGET_WAITKIND_EXITED:
1294 target_terminal_ours (); /* Must do this before mourn anyway */
1295 print_stop_reason (EXITED, ecs->ws.value.integer);
1297 /* Record the exit code in the convenience variable $_exitcode, so
1298 that the user can inspect this again later. */
1299 set_internalvar (lookup_internalvar ("_exitcode"),
1300 value_from_longest (builtin_type_int,
1301 (LONGEST) ecs->ws.value.integer));
1302 gdb_flush (gdb_stdout);
1303 target_mourn_inferior ();
1304 singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
1305 stop_print_frame = 0;
1306 stop_stepping (ecs);
1309 case TARGET_WAITKIND_SIGNALLED:
1310 stop_print_frame = 0;
1311 stop_signal = ecs->ws.value.sig;
1312 target_terminal_ours (); /* Must do this before mourn anyway */
1314 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
1315 reach here unless the inferior is dead. However, for years
1316 target_kill() was called here, which hints that fatal signals aren't
1317 really fatal on some systems. If that's true, then some changes
1319 target_mourn_inferior ();
1321 print_stop_reason (SIGNAL_EXITED, stop_signal);
1322 singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
1323 stop_stepping (ecs);
1326 /* The following are the only cases in which we keep going;
1327 the above cases end in a continue or goto. */
1328 case TARGET_WAITKIND_FORKED:
1329 case TARGET_WAITKIND_VFORKED:
1330 stop_signal = TARGET_SIGNAL_TRAP;
1331 pending_follow.kind = ecs->ws.kind;
1333 pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
1334 pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
1336 stop_pc = read_pc ();
1338 /* Assume that catchpoints are not really software breakpoints. If
1339 some future target implements them using software breakpoints then
1340 that target is responsible for fudging DECR_PC_AFTER_BREAK. Thus
1341 we pass 1 for the NOT_A_SW_BREAKPOINT argument, so that
1342 bpstat_stop_status will not decrement the PC. */
1344 stop_bpstat = bpstat_stop_status (&stop_pc, 1);
1346 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1347 goto process_event_stop_test;
1349 case TARGET_WAITKIND_EXECD:
1350 stop_signal = TARGET_SIGNAL_TRAP;
1352 /* NOTE drow/2002-12-05: This code should be pushed down into the
1353 target_wait function. Until then following vfork on HP/UX 10.20
1354 is probably broken by this. Of course, it's broken anyway. */
1355 /* Is this a target which reports multiple exec events per actual
1356 call to exec()? (HP-UX using ptrace does, for example.) If so,
1357 ignore all but the last one. Just resume the exec'r, and wait
1358 for the next exec event. */
1359 if (inferior_ignoring_leading_exec_events)
1361 inferior_ignoring_leading_exec_events--;
1362 if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
1363 ENSURE_VFORKING_PARENT_REMAINS_STOPPED (pending_follow.fork_event.
1365 target_resume (ecs->ptid, 0, TARGET_SIGNAL_0);
1366 prepare_to_wait (ecs);
1369 inferior_ignoring_leading_exec_events =
1370 target_reported_exec_events_per_exec_call () - 1;
1372 pending_follow.execd_pathname =
1373 savestring (ecs->ws.value.execd_pathname,
1374 strlen (ecs->ws.value.execd_pathname));
1376 /* This causes the eventpoints and symbol table to be reset. Must
1377 do this now, before trying to determine whether to stop. */
1378 follow_exec (PIDGET (inferior_ptid), pending_follow.execd_pathname);
1379 xfree (pending_follow.execd_pathname);
1381 stop_pc = read_pc_pid (ecs->ptid);
1382 ecs->saved_inferior_ptid = inferior_ptid;
1383 inferior_ptid = ecs->ptid;
1385 /* Assume that catchpoints are not really software breakpoints. If
1386 some future target implements them using software breakpoints then
1387 that target is responsible for fudging DECR_PC_AFTER_BREAK. Thus
1388 we pass 1 for the NOT_A_SW_BREAKPOINT argument, so that
1389 bpstat_stop_status will not decrement the PC. */
1391 stop_bpstat = bpstat_stop_status (&stop_pc, 1);
1393 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1394 inferior_ptid = ecs->saved_inferior_ptid;
1395 goto process_event_stop_test;
1397 /* These syscall events are returned on HP-UX, as part of its
1398 implementation of page-protection-based "hardware" watchpoints.
1399 HP-UX has unfortunate interactions between page-protections and
1400 some system calls. Our solution is to disable hardware watches
1401 when a system call is entered, and reenable them when the syscall
1402 completes. The downside of this is that we may miss the precise
1403 point at which a watched piece of memory is modified. "Oh well."
1405 Note that we may have multiple threads running, which may each
1406 enter syscalls at roughly the same time. Since we don't have a
1407 good notion currently of whether a watched piece of memory is
1408 thread-private, we'd best not have any page-protections active
1409 when any thread is in a syscall. Thus, we only want to reenable
1410 hardware watches when no threads are in a syscall.
1412 Also, be careful not to try to gather much state about a thread
1413 that's in a syscall. It's frequently a losing proposition. */
1414 case TARGET_WAITKIND_SYSCALL_ENTRY:
1415 number_of_threads_in_syscalls++;
1416 if (number_of_threads_in_syscalls == 1)
1418 TARGET_DISABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
1420 resume (0, TARGET_SIGNAL_0);
1421 prepare_to_wait (ecs);
1424 /* Before examining the threads further, step this thread to
1425 get it entirely out of the syscall. (We get notice of the
1426 event when the thread is just on the verge of exiting a
1427 syscall. Stepping one instruction seems to get it back
1430 Note that although the logical place to reenable h/w watches
1431 is here, we cannot. We cannot reenable them before stepping
1432 the thread (this causes the next wait on the thread to hang).
1434 Nor can we enable them after stepping until we've done a wait.
1435 Thus, we simply set the flag ecs->enable_hw_watchpoints_after_wait
1436 here, which will be serviced immediately after the target
1438 case TARGET_WAITKIND_SYSCALL_RETURN:
1439 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1441 if (number_of_threads_in_syscalls > 0)
1443 number_of_threads_in_syscalls--;
1444 ecs->enable_hw_watchpoints_after_wait =
1445 (number_of_threads_in_syscalls == 0);
1447 prepare_to_wait (ecs);
1450 case TARGET_WAITKIND_STOPPED:
1451 stop_signal = ecs->ws.value.sig;
1454 /* We had an event in the inferior, but we are not interested
1455 in handling it at this level. The lower layers have already
1456 done what needs to be done, if anything.
1458 One of the possible circumstances for this is when the
1459 inferior produces output for the console. The inferior has
1460 not stopped, and we are ignoring the event. Another possible
1461 circumstance is any event which the lower level knows will be
1462 reported multiple times without an intervening resume. */
1463 case TARGET_WAITKIND_IGNORE:
1464 prepare_to_wait (ecs);
1468 /* We may want to consider not doing a resume here in order to give
1469 the user a chance to play with the new thread. It might be good
1470 to make that a user-settable option. */
1472 /* At this point, all threads are stopped (happens automatically in
1473 either the OS or the native code). Therefore we need to continue
1474 all threads in order to make progress. */
1475 if (ecs->new_thread_event)
1477 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
1478 prepare_to_wait (ecs);
1482 stop_pc = read_pc_pid (ecs->ptid);
1484 /* See if a thread hit a thread-specific breakpoint that was meant for
1485 another thread. If so, then step that thread past the breakpoint,
1488 if (stop_signal == TARGET_SIGNAL_TRAP)
1490 /* Check if a regular breakpoint has been hit before checking
1491 for a potential single step breakpoint. Otherwise, GDB will
1492 not see this breakpoint hit when stepping onto breakpoints. */
1493 if (breakpoints_inserted
1494 && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK))
1496 ecs->random_signal = 0;
1497 if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK,
1502 /* Saw a breakpoint, but it was hit by the wrong thread.
1504 if (DECR_PC_AFTER_BREAK)
1505 write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, ecs->ptid);
1507 remove_status = remove_breakpoints ();
1508 /* Did we fail to remove breakpoints? If so, try
1509 to set the PC past the bp. (There's at least
1510 one situation in which we can fail to remove
1511 the bp's: On HP-UX's that use ttrace, we can't
1512 change the address space of a vforking child
1513 process until the child exits (well, okay, not
1514 then either :-) or execs. */
1515 if (remove_status != 0)
1517 /* FIXME! This is obviously non-portable! */
1518 write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK + 4, ecs->ptid);
1519 /* We need to restart all the threads now,
1520 * unles we're running in scheduler-locked mode.
1521 * Use currently_stepping to determine whether to
1524 /* FIXME MVS: is there any reason not to call resume()? */
1525 if (scheduler_mode == schedlock_on)
1526 target_resume (ecs->ptid,
1527 currently_stepping (ecs), TARGET_SIGNAL_0);
1529 target_resume (RESUME_ALL,
1530 currently_stepping (ecs), TARGET_SIGNAL_0);
1531 prepare_to_wait (ecs);
1536 breakpoints_inserted = 0;
1537 if (!ptid_equal (inferior_ptid, ecs->ptid))
1538 context_switch (ecs);
1539 ecs->waiton_ptid = ecs->ptid;
1540 ecs->wp = &(ecs->ws);
1541 ecs->another_trap = 1;
1543 ecs->infwait_state = infwait_thread_hop_state;
1545 registers_changed ();
1550 else if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
1552 /* Readjust the stop_pc as it is off by DECR_PC_AFTER_BREAK
1553 compared to the value it would have if the system stepping
1554 capability was used. This allows the rest of the code in
1555 this function to use this address without having to worry
1556 whether software single step is in use or not. */
1557 if (DECR_PC_AFTER_BREAK)
1559 stop_pc -= DECR_PC_AFTER_BREAK;
1560 write_pc_pid (stop_pc, ecs->ptid);
1563 sw_single_step_trap_p = 1;
1564 ecs->random_signal = 0;
1568 ecs->random_signal = 1;
1570 /* See if something interesting happened to the non-current thread. If
1571 so, then switch to that thread, and eventually give control back to
1574 Note that if there's any kind of pending follow (i.e., of a fork,
1575 vfork or exec), we don't want to do this now. Rather, we'll let
1576 the next resume handle it. */
1577 if (!ptid_equal (ecs->ptid, inferior_ptid) &&
1578 (pending_follow.kind == TARGET_WAITKIND_SPURIOUS))
1582 /* If it's a random signal for a non-current thread, notify user
1583 if he's expressed an interest. */
1584 if (ecs->random_signal && signal_print[stop_signal])
1586 /* ??rehrauer: I don't understand the rationale for this code. If the
1587 inferior will stop as a result of this signal, then the act of handling
1588 the stop ought to print a message that's couches the stoppage in user
1589 terms, e.g., "Stopped for breakpoint/watchpoint". If the inferior
1590 won't stop as a result of the signal -- i.e., if the signal is merely
1591 a side-effect of something GDB's doing "under the covers" for the
1592 user, such as stepping threads over a breakpoint they shouldn't stop
1593 for -- then the message seems to be a serious annoyance at best.
1595 For now, remove the message altogether. */
1598 target_terminal_ours_for_output ();
1599 printf_filtered ("\nProgram received signal %s, %s.\n",
1600 target_signal_to_name (stop_signal),
1601 target_signal_to_string (stop_signal));
1602 gdb_flush (gdb_stdout);
1606 /* If it's not SIGTRAP and not a signal we want to stop for, then
1607 continue the thread. */
1609 if (stop_signal != TARGET_SIGNAL_TRAP && !signal_stop[stop_signal])
1612 target_terminal_inferior ();
1614 /* Clear the signal if it should not be passed. */
1615 if (signal_program[stop_signal] == 0)
1616 stop_signal = TARGET_SIGNAL_0;
1618 target_resume (ecs->ptid, 0, stop_signal);
1619 prepare_to_wait (ecs);
1623 /* It's a SIGTRAP or a signal we're interested in. Switch threads,
1624 and fall into the rest of wait_for_inferior(). */
1626 context_switch (ecs);
1629 context_hook (pid_to_thread_id (ecs->ptid));
1631 flush_cached_frames ();
1634 if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
1636 /* Pull the single step breakpoints out of the target. */
1637 SOFTWARE_SINGLE_STEP (0, 0);
1638 singlestep_breakpoints_inserted_p = 0;
1641 /* If PC is pointing at a nullified instruction, then step beyond
1642 it so that the user won't be confused when GDB appears to be ready
1645 /* if (INSTRUCTION_NULLIFIED && currently_stepping (ecs)) */
1646 if (INSTRUCTION_NULLIFIED)
1648 registers_changed ();
1649 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1651 /* We may have received a signal that we want to pass to
1652 the inferior; therefore, we must not clobber the waitstatus
1655 ecs->infwait_state = infwait_nullified_state;
1656 ecs->waiton_ptid = ecs->ptid;
1657 ecs->wp = &(ecs->tmpstatus);
1658 prepare_to_wait (ecs);
1662 /* It may not be necessary to disable the watchpoint to stop over
1663 it. For example, the PA can (with some kernel cooperation)
1664 single step over a watchpoint without disabling the watchpoint. */
1665 if (HAVE_STEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
1668 prepare_to_wait (ecs);
1672 /* It is far more common to need to disable a watchpoint to step
1673 the inferior over it. FIXME. What else might a debug
1674 register or page protection watchpoint scheme need here? */
1675 if (HAVE_NONSTEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
1677 /* At this point, we are stopped at an instruction which has
1678 attempted to write to a piece of memory under control of
1679 a watchpoint. The instruction hasn't actually executed
1680 yet. If we were to evaluate the watchpoint expression
1681 now, we would get the old value, and therefore no change
1682 would seem to have occurred.
1684 In order to make watchpoints work `right', we really need
1685 to complete the memory write, and then evaluate the
1686 watchpoint expression. The following code does that by
1687 removing the watchpoint (actually, all watchpoints and
1688 breakpoints), single-stepping the target, re-inserting
1689 watchpoints, and then falling through to let normal
1690 single-step processing handle proceed. Since this
1691 includes evaluating watchpoints, things will come to a
1692 stop in the correct manner. */
1694 if (DECR_PC_AFTER_BREAK)
1695 write_pc (stop_pc - DECR_PC_AFTER_BREAK);
1697 remove_breakpoints ();
1698 registers_changed ();
1699 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */
1701 ecs->waiton_ptid = ecs->ptid;
1702 ecs->wp = &(ecs->ws);
1703 ecs->infwait_state = infwait_nonstep_watch_state;
1704 prepare_to_wait (ecs);
1708 /* It may be possible to simply continue after a watchpoint. */
1709 if (HAVE_CONTINUABLE_WATCHPOINT)
1710 STOPPED_BY_WATCHPOINT (ecs->ws);
1712 ecs->stop_func_start = 0;
1713 ecs->stop_func_end = 0;
1714 ecs->stop_func_name = 0;
1715 /* Don't care about return value; stop_func_start and stop_func_name
1716 will both be 0 if it doesn't work. */
1717 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
1718 &ecs->stop_func_start, &ecs->stop_func_end);
1719 ecs->stop_func_start += FUNCTION_START_OFFSET;
1720 ecs->another_trap = 0;
1721 bpstat_clear (&stop_bpstat);
1723 stop_stack_dummy = 0;
1724 stop_print_frame = 1;
1725 ecs->random_signal = 0;
1726 stopped_by_random_signal = 0;
1727 breakpoints_failed = 0;
1729 /* Look at the cause of the stop, and decide what to do.
1730 The alternatives are:
1731 1) break; to really stop and return to the debugger,
1732 2) drop through to start up again
1733 (set ecs->another_trap to 1 to single step once)
1734 3) set ecs->random_signal to 1, and the decision between 1 and 2
1735 will be made according to the signal handling tables. */
1737 /* First, distinguish signals caused by the debugger from signals
1738 that have to do with the program's own actions.
1739 Note that breakpoint insns may cause SIGTRAP or SIGILL
1740 or SIGEMT, depending on the operating system version.
1741 Here we detect when a SIGILL or SIGEMT is really a breakpoint
1742 and change it to SIGTRAP. */
1744 if (stop_signal == TARGET_SIGNAL_TRAP
1745 || (breakpoints_inserted &&
1746 (stop_signal == TARGET_SIGNAL_ILL
1747 || stop_signal == TARGET_SIGNAL_EMT)) || stop_soon_quietly)
1749 if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
1751 stop_print_frame = 0;
1752 stop_stepping (ecs);
1755 if (stop_soon_quietly)
1757 stop_stepping (ecs);
1761 /* Don't even think about breakpoints
1762 if just proceeded over a breakpoint.
1764 However, if we are trying to proceed over a breakpoint
1765 and end up in sigtramp, then through_sigtramp_breakpoint
1766 will be set and we should check whether we've hit the
1768 if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected
1769 && through_sigtramp_breakpoint == NULL)
1770 bpstat_clear (&stop_bpstat);
1773 /* See if there is a breakpoint at the current PC. */
1775 /* The second argument of bpstat_stop_status is meant to help
1776 distinguish between a breakpoint trap and a singlestep trap.
1777 This is only important on targets where DECR_PC_AFTER_BREAK
1778 is non-zero. The prev_pc test is meant to distinguish between
1779 singlestepping a trap instruction, and singlestepping thru a
1780 jump to the instruction following a trap instruction.
1782 Therefore, pass TRUE if our reason for stopping is
1783 something other than hitting a breakpoint. We do this by
1784 checking that either: we detected earlier a software single
1785 step trap or, 1) stepping is going on and 2) we didn't hit
1786 a breakpoint in a signal handler without an intervening stop
1787 in sigtramp, which is detected by a new stack pointer value
1788 below any usual function calling stack adjustments. */
1792 sw_single_step_trap_p
1793 || (currently_stepping (ecs)
1794 && prev_pc != stop_pc - DECR_PC_AFTER_BREAK
1796 && INNER_THAN (read_sp (), (step_sp - 16)))));
1797 /* Following in case break condition called a
1799 stop_print_frame = 1;
1802 if (stop_signal == TARGET_SIGNAL_TRAP)
1804 = !(bpstat_explains_signal (stop_bpstat)
1806 || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
1807 && DEPRECATED_PC_IN_CALL_DUMMY (stop_pc, read_sp (),
1808 get_frame_base (get_current_frame ())))
1809 || (step_range_end && step_resume_breakpoint == NULL));
1813 ecs->random_signal = !(bpstat_explains_signal (stop_bpstat)
1814 /* End of a stack dummy. Some systems (e.g. Sony
1815 news) give another signal besides SIGTRAP, so
1816 check here as well as above. */
1817 || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
1818 && DEPRECATED_PC_IN_CALL_DUMMY (stop_pc, read_sp (),
1822 if (!ecs->random_signal)
1823 stop_signal = TARGET_SIGNAL_TRAP;
1827 /* When we reach this point, we've pretty much decided
1828 that the reason for stopping must've been a random
1829 (unexpected) signal. */
1832 ecs->random_signal = 1;
1833 /* If a fork, vfork or exec event was seen, then there are two
1834 possible responses we can make:
1836 1. If a catchpoint triggers for the event (ecs->random_signal == 0),
1837 then we must stop now and issue a prompt. We will resume
1838 the inferior when the user tells us to.
1839 2. If no catchpoint triggers for the event (ecs->random_signal == 1),
1840 then we must resume the inferior now and keep checking.
1842 In either case, we must take appropriate steps to "follow" the
1843 the fork/vfork/exec when the inferior is resumed. For example,
1844 if follow-fork-mode is "child", then we must detach from the
1845 parent inferior and follow the new child inferior.
1847 In either case, setting pending_follow causes the next resume()
1848 to take the appropriate following action. */
1849 process_event_stop_test:
1850 if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
1852 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
1855 stop_signal = TARGET_SIGNAL_0;
1860 else if (ecs->ws.kind == TARGET_WAITKIND_VFORKED)
1862 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
1864 stop_signal = TARGET_SIGNAL_0;
1869 else if (ecs->ws.kind == TARGET_WAITKIND_EXECD)
1871 pending_follow.kind = ecs->ws.kind;
1872 if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
1875 stop_signal = TARGET_SIGNAL_0;
1881 /* For the program's own signals, act according to
1882 the signal handling tables. */
1884 if (ecs->random_signal)
1886 /* Signal not for debugging purposes. */
1889 stopped_by_random_signal = 1;
1891 if (signal_print[stop_signal])
1894 target_terminal_ours_for_output ();
1895 print_stop_reason (SIGNAL_RECEIVED, stop_signal);
1897 if (signal_stop[stop_signal])
1899 stop_stepping (ecs);
1902 /* If not going to stop, give terminal back
1903 if we took it away. */
1905 target_terminal_inferior ();
1907 /* Clear the signal if it should not be passed. */
1908 if (signal_program[stop_signal] == 0)
1909 stop_signal = TARGET_SIGNAL_0;
1911 /* I'm not sure whether this needs to be check_sigtramp2 or
1912 whether it could/should be keep_going.
1914 This used to jump to step_over_function if we are stepping,
1917 Suppose the user does a `next' over a function call, and while
1918 that call is in progress, the inferior receives a signal for
1919 which GDB does not stop (i.e., signal_stop[SIG] is false). In
1920 that case, when we reach this point, there is already a
1921 step-resume breakpoint established, right where it should be:
1922 immediately after the function call the user is "next"-ing
1923 over. If we call step_over_function now, two bad things
1926 - we'll create a new breakpoint, at wherever the current
1927 frame's return address happens to be. That could be
1928 anywhere, depending on what function call happens to be on
1929 the top of the stack at that point. Point is, it's probably
1930 not where we need it.
1932 - the existing step-resume breakpoint (which is at the correct
1933 address) will get orphaned: step_resume_breakpoint will point
1934 to the new breakpoint, and the old step-resume breakpoint
1935 will never be cleaned up.
1937 The old behavior was meant to help HP-UX single-step out of
1938 sigtramps. It would place the new breakpoint at prev_pc, which
1939 was certainly wrong. I don't know the details there, so fixing
1940 this probably breaks that. As with anything else, it's up to
1941 the HP-UX maintainer to furnish a fix that doesn't break other
1942 platforms. --JimB, 20 May 1999 */
1943 check_sigtramp2 (ecs);
1948 /* Handle cases caused by hitting a breakpoint. */
1950 CORE_ADDR jmp_buf_pc;
1951 struct bpstat_what what;
1953 what = bpstat_what (stop_bpstat);
1955 if (what.call_dummy)
1957 stop_stack_dummy = 1;
1959 trap_expected_after_continue = 1;
1963 switch (what.main_action)
1965 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
1966 /* If we hit the breakpoint at longjmp, disable it for the
1967 duration of this command. Then, install a temporary
1968 breakpoint at the target of the jmp_buf. */
1969 disable_longjmp_breakpoint ();
1970 remove_breakpoints ();
1971 breakpoints_inserted = 0;
1972 if (!GET_LONGJMP_TARGET_P () || !GET_LONGJMP_TARGET (&jmp_buf_pc))
1978 /* Need to blow away step-resume breakpoint, as it
1979 interferes with us */
1980 if (step_resume_breakpoint != NULL)
1982 delete_step_resume_breakpoint (&step_resume_breakpoint);
1984 /* Not sure whether we need to blow this away too, but probably
1985 it is like the step-resume breakpoint. */
1986 if (through_sigtramp_breakpoint != NULL)
1988 delete_breakpoint (through_sigtramp_breakpoint);
1989 through_sigtramp_breakpoint = NULL;
1993 /* FIXME - Need to implement nested temporary breakpoints */
1994 if (step_over_calls > 0)
1995 set_longjmp_resume_breakpoint (jmp_buf_pc, get_current_frame ());
1998 set_longjmp_resume_breakpoint (jmp_buf_pc, null_frame_id);
1999 ecs->handling_longjmp = 1; /* FIXME */
2003 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
2004 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
2005 remove_breakpoints ();
2006 breakpoints_inserted = 0;
2008 /* FIXME - Need to implement nested temporary breakpoints */
2010 && (frame_id_inner (get_frame_id (get_current_frame ()),
2013 ecs->another_trap = 1;
2018 disable_longjmp_breakpoint ();
2019 ecs->handling_longjmp = 0; /* FIXME */
2020 if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
2022 /* else fallthrough */
2024 case BPSTAT_WHAT_SINGLE:
2025 if (breakpoints_inserted)
2027 remove_breakpoints ();
2029 breakpoints_inserted = 0;
2030 ecs->another_trap = 1;
2031 /* Still need to check other stuff, at least the case
2032 where we are stepping and step out of the right range. */
2035 case BPSTAT_WHAT_STOP_NOISY:
2036 stop_print_frame = 1;
2038 /* We are about to nuke the step_resume_breakpoint and
2039 through_sigtramp_breakpoint via the cleanup chain, so
2040 no need to worry about it here. */
2042 stop_stepping (ecs);
2045 case BPSTAT_WHAT_STOP_SILENT:
2046 stop_print_frame = 0;
2048 /* We are about to nuke the step_resume_breakpoint and
2049 through_sigtramp_breakpoint via the cleanup chain, so
2050 no need to worry about it here. */
2052 stop_stepping (ecs);
2055 case BPSTAT_WHAT_STEP_RESUME:
2056 /* This proably demands a more elegant solution, but, yeah
2059 This function's use of the simple variable
2060 step_resume_breakpoint doesn't seem to accomodate
2061 simultaneously active step-resume bp's, although the
2062 breakpoint list certainly can.
2064 If we reach here and step_resume_breakpoint is already
2065 NULL, then apparently we have multiple active
2066 step-resume bp's. We'll just delete the breakpoint we
2067 stopped at, and carry on.
2069 Correction: what the code currently does is delete a
2070 step-resume bp, but it makes no effort to ensure that
2071 the one deleted is the one currently stopped at. MVS */
2073 if (step_resume_breakpoint == NULL)
2075 step_resume_breakpoint =
2076 bpstat_find_step_resume_breakpoint (stop_bpstat);
2078 delete_step_resume_breakpoint (&step_resume_breakpoint);
2081 case BPSTAT_WHAT_THROUGH_SIGTRAMP:
2082 if (through_sigtramp_breakpoint)
2083 delete_breakpoint (through_sigtramp_breakpoint);
2084 through_sigtramp_breakpoint = NULL;
2086 /* If were waiting for a trap, hitting the step_resume_break
2087 doesn't count as getting it. */
2089 ecs->another_trap = 1;
2092 case BPSTAT_WHAT_CHECK_SHLIBS:
2093 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
2096 /* Remove breakpoints, we eventually want to step over the
2097 shlib event breakpoint, and SOLIB_ADD might adjust
2098 breakpoint addresses via breakpoint_re_set. */
2099 if (breakpoints_inserted)
2100 remove_breakpoints ();
2101 breakpoints_inserted = 0;
2103 /* Check for any newly added shared libraries if we're
2104 supposed to be adding them automatically. Switch
2105 terminal for any messages produced by
2106 breakpoint_re_set. */
2107 target_terminal_ours_for_output ();
2108 SOLIB_ADD (NULL, 0, NULL, auto_solib_add);
2109 target_terminal_inferior ();
2111 /* Try to reenable shared library breakpoints, additional
2112 code segments in shared libraries might be mapped in now. */
2113 re_enable_breakpoints_in_shlibs ();
2115 /* If requested, stop when the dynamic linker notifies
2116 gdb of events. This allows the user to get control
2117 and place breakpoints in initializer routines for
2118 dynamically loaded objects (among other things). */
2119 if (stop_on_solib_events)
2121 stop_stepping (ecs);
2125 /* If we stopped due to an explicit catchpoint, then the
2126 (see above) call to SOLIB_ADD pulled in any symbols
2127 from a newly-loaded library, if appropriate.
2129 We do want the inferior to stop, but not where it is
2130 now, which is in the dynamic linker callback. Rather,
2131 we would like it stop in the user's program, just after
2132 the call that caused this catchpoint to trigger. That
2133 gives the user a more useful vantage from which to
2134 examine their program's state. */
2135 else if (what.main_action ==
2136 BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
2138 /* ??rehrauer: If I could figure out how to get the
2139 right return PC from here, we could just set a temp
2140 breakpoint and resume. I'm not sure we can without
2141 cracking open the dld's shared libraries and sniffing
2142 their unwind tables and text/data ranges, and that's
2143 not a terribly portable notion.
2145 Until that time, we must step the inferior out of the
2146 dld callback, and also out of the dld itself (and any
2147 code or stubs in libdld.sl, such as "shl_load" and
2148 friends) until we reach non-dld code. At that point,
2149 we can stop stepping. */
2150 bpstat_get_triggered_catchpoints (stop_bpstat,
2152 stepping_through_solib_catchpoints);
2153 ecs->stepping_through_solib_after_catch = 1;
2155 /* Be sure to lift all breakpoints, so the inferior does
2156 actually step past this point... */
2157 ecs->another_trap = 1;
2162 /* We want to step over this breakpoint, then keep going. */
2163 ecs->another_trap = 1;
2170 case BPSTAT_WHAT_LAST:
2171 /* Not a real code, but listed here to shut up gcc -Wall. */
2173 case BPSTAT_WHAT_KEEP_CHECKING:
2178 /* We come here if we hit a breakpoint but should not
2179 stop for it. Possibly we also were stepping
2180 and should stop for that. So fall through and
2181 test for stepping. But, if not stepping,
2184 /* Are we stepping to get the inferior out of the dynamic
2185 linker's hook (and possibly the dld itself) after catching
2187 if (ecs->stepping_through_solib_after_catch)
2189 #if defined(SOLIB_ADD)
2190 /* Have we reached our destination? If not, keep going. */
2191 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc))
2193 ecs->another_trap = 1;
2198 /* Else, stop and report the catchpoint(s) whose triggering
2199 caused us to begin stepping. */
2200 ecs->stepping_through_solib_after_catch = 0;
2201 bpstat_clear (&stop_bpstat);
2202 stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints);
2203 bpstat_clear (&ecs->stepping_through_solib_catchpoints);
2204 stop_print_frame = 1;
2205 stop_stepping (ecs);
2209 if (!CALL_DUMMY_BREAKPOINT_OFFSET_P)
2211 /* This is the old way of detecting the end of the stack dummy.
2212 An architecture which defines CALL_DUMMY_BREAKPOINT_OFFSET gets
2213 handled above. As soon as we can test it on all of them, all
2214 architectures should define it. */
2216 /* If this is the breakpoint at the end of a stack dummy,
2217 just stop silently, unless the user was doing an si/ni, in which
2218 case she'd better know what she's doing. */
2220 if (CALL_DUMMY_HAS_COMPLETED (stop_pc, read_sp (),
2221 get_frame_base (get_current_frame ()))
2224 stop_print_frame = 0;
2225 stop_stack_dummy = 1;
2227 trap_expected_after_continue = 1;
2229 stop_stepping (ecs);
2234 if (step_resume_breakpoint)
2236 /* Having a step-resume breakpoint overrides anything
2237 else having to do with stepping commands until
2238 that breakpoint is reached. */
2239 /* I'm not sure whether this needs to be check_sigtramp2 or
2240 whether it could/should be keep_going. */
2241 check_sigtramp2 (ecs);
2246 if (step_range_end == 0)
2248 /* Likewise if we aren't even stepping. */
2249 /* I'm not sure whether this needs to be check_sigtramp2 or
2250 whether it could/should be keep_going. */
2251 check_sigtramp2 (ecs);
2256 /* If stepping through a line, keep going if still within it.
2258 Note that step_range_end is the address of the first instruction
2259 beyond the step range, and NOT the address of the last instruction
2261 if (stop_pc >= step_range_start && stop_pc < step_range_end)
2263 /* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal.
2264 So definately need to check for sigtramp here. */
2265 check_sigtramp2 (ecs);
2270 /* We stepped out of the stepping range. */
2272 /* If we are stepping at the source level and entered the runtime
2273 loader dynamic symbol resolution code, we keep on single stepping
2274 until we exit the run time loader code and reach the callee's
2276 if (step_over_calls == STEP_OVER_UNDEBUGGABLE
2277 && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc))
2279 CORE_ADDR pc_after_resolver = SKIP_SOLIB_RESOLVER (stop_pc);
2281 if (pc_after_resolver)
2283 /* Set up a step-resume breakpoint at the address
2284 indicated by SKIP_SOLIB_RESOLVER. */
2285 struct symtab_and_line sr_sal;
2287 sr_sal.pc = pc_after_resolver;
2289 check_for_old_step_resume_breakpoint ();
2290 step_resume_breakpoint =
2291 set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
2292 if (breakpoints_inserted)
2293 insert_breakpoints ();
2300 /* We can't update step_sp every time through the loop, because
2301 reading the stack pointer would slow down stepping too much.
2302 But we can update it every time we leave the step range. */
2303 ecs->update_step_sp = 1;
2305 /* Did we just take a signal? */
2306 if (PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2307 && !PC_IN_SIGTRAMP (prev_pc, prev_func_name)
2308 && INNER_THAN (read_sp (), step_sp))
2310 /* We've just taken a signal; go until we are back to
2311 the point where we took it and one more. */
2313 /* Note: The test above succeeds not only when we stepped
2314 into a signal handler, but also when we step past the last
2315 statement of a signal handler and end up in the return stub
2316 of the signal handler trampoline. To distinguish between
2317 these two cases, check that the frame is INNER_THAN the
2318 previous one below. pai/1997-09-11 */
2322 struct frame_id current_frame = get_frame_id (get_current_frame ());
2324 if (frame_id_inner (current_frame, step_frame_id))
2326 /* We have just taken a signal; go until we are back to
2327 the point where we took it and one more. */
2329 /* This code is needed at least in the following case:
2330 The user types "next" and then a signal arrives (before
2331 the "next" is done). */
2333 /* Note that if we are stopped at a breakpoint, then we need
2334 the step_resume breakpoint to override any breakpoints at
2335 the same location, so that we will still step over the
2336 breakpoint even though the signal happened. */
2337 struct symtab_and_line sr_sal;
2340 sr_sal.symtab = NULL;
2342 sr_sal.pc = prev_pc;
2343 /* We could probably be setting the frame to
2344 step_frame_id; I don't think anyone thought to try it. */
2345 check_for_old_step_resume_breakpoint ();
2346 step_resume_breakpoint =
2347 set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
2348 if (breakpoints_inserted)
2349 insert_breakpoints ();
2353 /* We just stepped out of a signal handler and into
2354 its calling trampoline.
2356 Normally, we'd call step_over_function from
2357 here, but for some reason GDB can't unwind the
2358 stack correctly to find the real PC for the point
2359 user code where the signal trampoline will return
2360 -- FRAME_SAVED_PC fails, at least on HP-UX 10.20.
2361 But signal trampolines are pretty small stubs of
2362 code, anyway, so it's OK instead to just
2363 single-step out. Note: assuming such trampolines
2364 don't exhibit recursion on any platform... */
2365 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
2366 &ecs->stop_func_start,
2367 &ecs->stop_func_end);
2368 /* Readjust stepping range */
2369 step_range_start = ecs->stop_func_start;
2370 step_range_end = ecs->stop_func_end;
2371 ecs->stepping_through_sigtramp = 1;
2376 /* If this is stepi or nexti, make sure that the stepping range
2377 gets us past that instruction. */
2378 if (step_range_end == 1)
2379 /* FIXME: Does this run afoul of the code below which, if
2380 we step into the middle of a line, resets the stepping
2382 step_range_end = (step_range_start = prev_pc) + 1;
2384 ecs->remove_breakpoints_on_following_step = 1;
2389 if (stop_pc == ecs->stop_func_start /* Quick test */
2390 || (in_prologue (stop_pc, ecs->stop_func_start) &&
2391 !IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2392 || IN_SOLIB_CALL_TRAMPOLINE (stop_pc, ecs->stop_func_name)
2393 || ecs->stop_func_name == 0)
2395 /* It's a subroutine call. */
2397 if ((step_over_calls == STEP_OVER_NONE)
2398 || ((step_range_end == 1)
2399 && in_prologue (prev_pc, ecs->stop_func_start)))
2401 /* I presume that step_over_calls is only 0 when we're
2402 supposed to be stepping at the assembly language level
2403 ("stepi"). Just stop. */
2404 /* Also, maybe we just did a "nexti" inside a prolog,
2405 so we thought it was a subroutine call but it was not.
2406 Stop as well. FENN */
2408 print_stop_reason (END_STEPPING_RANGE, 0);
2409 stop_stepping (ecs);
2413 if (step_over_calls == STEP_OVER_ALL || IGNORE_HELPER_CALL (stop_pc))
2415 /* We're doing a "next". */
2417 if (PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2418 && frame_id_inner (step_frame_id,
2419 frame_id_build (read_sp (), 0)))
2420 /* We stepped out of a signal handler, and into its
2421 calling trampoline. This is misdetected as a
2422 subroutine call, but stepping over the signal
2423 trampoline isn't such a bad idea. In order to do that,
2424 we have to ignore the value in step_frame_id, since
2425 that doesn't represent the frame that'll reach when we
2426 return from the signal trampoline. Otherwise we'll
2427 probably continue to the end of the program. */
2428 step_frame_id = null_frame_id;
2430 step_over_function (ecs);
2435 /* If we are in a function call trampoline (a stub between
2436 the calling routine and the real function), locate the real
2437 function. That's what tells us (a) whether we want to step
2438 into it at all, and (b) what prologue we want to run to
2439 the end of, if we do step into it. */
2440 tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
2442 ecs->stop_func_start = tmp;
2445 tmp = DYNAMIC_TRAMPOLINE_NEXTPC (stop_pc);
2448 struct symtab_and_line xxx;
2449 /* Why isn't this s_a_l called "sr_sal", like all of the
2450 other s_a_l's where this code is duplicated? */
2451 init_sal (&xxx); /* initialize to zeroes */
2453 xxx.section = find_pc_overlay (xxx.pc);
2454 check_for_old_step_resume_breakpoint ();
2455 step_resume_breakpoint =
2456 set_momentary_breakpoint (xxx, null_frame_id, bp_step_resume);
2457 insert_breakpoints ();
2463 /* If we have line number information for the function we
2464 are thinking of stepping into, step into it.
2466 If there are several symtabs at that PC (e.g. with include
2467 files), just want to know whether *any* of them have line
2468 numbers. find_pc_line handles this. */
2470 struct symtab_and_line tmp_sal;
2472 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
2473 if (tmp_sal.line != 0)
2475 step_into_function (ecs);
2480 /* If we have no line number and the step-stop-if-no-debug
2481 is set, we stop the step so that the user has a chance to
2482 switch in assembly mode. */
2483 if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug)
2486 print_stop_reason (END_STEPPING_RANGE, 0);
2487 stop_stepping (ecs);
2491 step_over_function (ecs);
2497 /* We've wandered out of the step range. */
2499 ecs->sal = find_pc_line (stop_pc, 0);
2501 if (step_range_end == 1)
2503 /* It is stepi or nexti. We always want to stop stepping after
2506 print_stop_reason (END_STEPPING_RANGE, 0);
2507 stop_stepping (ecs);
2511 /* If we're in the return path from a shared library trampoline,
2512 we want to proceed through the trampoline when stepping. */
2513 if (IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2517 /* Determine where this trampoline returns. */
2518 tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
2520 /* Only proceed through if we know where it's going. */
2523 /* And put the step-breakpoint there and go until there. */
2524 struct symtab_and_line sr_sal;
2526 init_sal (&sr_sal); /* initialize to zeroes */
2528 sr_sal.section = find_pc_overlay (sr_sal.pc);
2529 /* Do not specify what the fp should be when we stop
2530 since on some machines the prologue
2531 is where the new fp value is established. */
2532 check_for_old_step_resume_breakpoint ();
2533 step_resume_breakpoint =
2534 set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
2535 if (breakpoints_inserted)
2536 insert_breakpoints ();
2538 /* Restart without fiddling with the step ranges or
2545 if (ecs->sal.line == 0)
2547 /* We have no line number information. That means to stop
2548 stepping (does this always happen right after one instruction,
2549 when we do "s" in a function with no line numbers,
2550 or can this happen as a result of a return or longjmp?). */
2552 print_stop_reason (END_STEPPING_RANGE, 0);
2553 stop_stepping (ecs);
2557 if ((stop_pc == ecs->sal.pc)
2558 && (ecs->current_line != ecs->sal.line
2559 || ecs->current_symtab != ecs->sal.symtab))
2561 /* We are at the start of a different line. So stop. Note that
2562 we don't stop if we step into the middle of a different line.
2563 That is said to make things like for (;;) statements work
2566 print_stop_reason (END_STEPPING_RANGE, 0);
2567 stop_stepping (ecs);
2571 /* We aren't done stepping.
2573 Optimize by setting the stepping range to the line.
2574 (We might not be in the original line, but if we entered a
2575 new line in mid-statement, we continue stepping. This makes
2576 things like for(;;) statements work better.) */
2578 if (ecs->stop_func_end && ecs->sal.end >= ecs->stop_func_end)
2580 /* If this is the last line of the function, don't keep stepping
2581 (it would probably step us out of the function).
2582 This is particularly necessary for a one-line function,
2583 in which after skipping the prologue we better stop even though
2584 we will be in mid-line. */
2586 print_stop_reason (END_STEPPING_RANGE, 0);
2587 stop_stepping (ecs);
2590 step_range_start = ecs->sal.pc;
2591 step_range_end = ecs->sal.end;
2592 step_frame_id = get_frame_id (get_current_frame ());
2593 ecs->current_line = ecs->sal.line;
2594 ecs->current_symtab = ecs->sal.symtab;
2596 /* In the case where we just stepped out of a function into the
2597 middle of a line of the caller, continue stepping, but
2598 step_frame_id must be modified to current frame */
2600 struct frame_id current_frame = get_frame_id (get_current_frame ());
2601 if (!(frame_id_inner (current_frame, step_frame_id)))
2602 step_frame_id = current_frame;
2608 /* Are we in the middle of stepping? */
2611 currently_stepping (struct execution_control_state *ecs)
2613 return ((through_sigtramp_breakpoint == NULL
2614 && !ecs->handling_longjmp
2615 && ((step_range_end && step_resume_breakpoint == NULL)
2617 || ecs->stepping_through_solib_after_catch
2618 || bpstat_should_step ());
2622 check_sigtramp2 (struct execution_control_state *ecs)
2625 && PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2626 && !PC_IN_SIGTRAMP (prev_pc, prev_func_name)
2627 && INNER_THAN (read_sp (), step_sp))
2629 /* What has happened here is that we have just stepped the
2630 inferior with a signal (because it is a signal which
2631 shouldn't make us stop), thus stepping into sigtramp.
2633 So we need to set a step_resume_break_address breakpoint and
2634 continue until we hit it, and then step. FIXME: This should
2635 be more enduring than a step_resume breakpoint; we should
2636 know that we will later need to keep going rather than
2637 re-hitting the breakpoint here (see the testsuite,
2638 gdb.base/signals.exp where it says "exceedingly difficult"). */
2640 struct symtab_and_line sr_sal;
2642 init_sal (&sr_sal); /* initialize to zeroes */
2643 sr_sal.pc = prev_pc;
2644 sr_sal.section = find_pc_overlay (sr_sal.pc);
2645 /* We perhaps could set the frame if we kept track of what the
2646 frame corresponding to prev_pc was. But we don't, so don't. */
2647 through_sigtramp_breakpoint =
2648 set_momentary_breakpoint (sr_sal, null_frame_id, bp_through_sigtramp);
2649 if (breakpoints_inserted)
2650 insert_breakpoints ();
2652 ecs->remove_breakpoints_on_following_step = 1;
2653 ecs->another_trap = 1;
2657 /* Subroutine call with source code we should not step over. Do step
2658 to the first line of code in it. */
2661 step_into_function (struct execution_control_state *ecs)
2664 struct symtab_and_line sr_sal;
2666 s = find_pc_symtab (stop_pc);
2667 if (s && s->language != language_asm)
2668 ecs->stop_func_start = SKIP_PROLOGUE (ecs->stop_func_start);
2670 ecs->sal = find_pc_line (ecs->stop_func_start, 0);
2671 /* Use the step_resume_break to step until the end of the prologue,
2672 even if that involves jumps (as it seems to on the vax under
2674 /* If the prologue ends in the middle of a source line, continue to
2675 the end of that source line (if it is still within the function).
2676 Otherwise, just go to end of prologue. */
2677 #ifdef PROLOGUE_FIRSTLINE_OVERLAP
2678 /* no, don't either. It skips any code that's legitimately on the
2682 && ecs->sal.pc != ecs->stop_func_start
2683 && ecs->sal.end < ecs->stop_func_end)
2684 ecs->stop_func_start = ecs->sal.end;
2687 if (ecs->stop_func_start == stop_pc)
2689 /* We are already there: stop now. */
2691 print_stop_reason (END_STEPPING_RANGE, 0);
2692 stop_stepping (ecs);
2697 /* Put the step-breakpoint there and go until there. */
2698 init_sal (&sr_sal); /* initialize to zeroes */
2699 sr_sal.pc = ecs->stop_func_start;
2700 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
2701 /* Do not specify what the fp should be when we stop since on
2702 some machines the prologue is where the new fp value is
2704 check_for_old_step_resume_breakpoint ();
2705 step_resume_breakpoint =
2706 set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
2707 if (breakpoints_inserted)
2708 insert_breakpoints ();
2710 /* And make sure stepping stops right away then. */
2711 step_range_end = step_range_start;
2716 /* We've just entered a callee, and we wish to resume until it returns
2717 to the caller. Setting a step_resume breakpoint on the return
2718 address will catch a return from the callee.
2720 However, if the callee is recursing, we want to be careful not to
2721 catch returns of those recursive calls, but only of THIS instance
2724 To do this, we set the step_resume bp's frame to our current
2725 caller's frame (step_frame_id, which is set by the "next" or
2726 "until" command, before execution begins). */
2729 step_over_function (struct execution_control_state *ecs)
2731 struct symtab_and_line sr_sal;
2733 init_sal (&sr_sal); /* initialize to zeros */
2734 sr_sal.pc = ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ()));
2735 sr_sal.section = find_pc_overlay (sr_sal.pc);
2737 check_for_old_step_resume_breakpoint ();
2738 step_resume_breakpoint =
2739 set_momentary_breakpoint (sr_sal, get_frame_id (get_current_frame ()),
2742 if (frame_id_p (step_frame_id)
2743 && !IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
2744 step_resume_breakpoint->frame_id = step_frame_id;
2746 if (breakpoints_inserted)
2747 insert_breakpoints ();
2751 stop_stepping (struct execution_control_state *ecs)
2753 if (target_has_execution)
2755 /* Assuming the inferior still exists, set these up for next
2756 time, just like we did above if we didn't break out of the
2758 prev_pc = read_pc ();
2759 prev_func_start = ecs->stop_func_start;
2760 prev_func_name = ecs->stop_func_name;
2763 /* Let callers know we don't want to wait for the inferior anymore. */
2764 ecs->wait_some_more = 0;
2767 /* This function handles various cases where we need to continue
2768 waiting for the inferior. */
2769 /* (Used to be the keep_going: label in the old wait_for_inferior) */
2772 keep_going (struct execution_control_state *ecs)
2774 /* Save the pc before execution, to compare with pc after stop. */
2775 prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
2776 prev_func_start = ecs->stop_func_start; /* Ok, since if DECR_PC_AFTER
2777 BREAK is defined, the
2778 original pc would not have
2779 been at the start of a
2781 prev_func_name = ecs->stop_func_name;
2783 if (ecs->update_step_sp)
2784 step_sp = read_sp ();
2785 ecs->update_step_sp = 0;
2787 /* If we did not do break;, it means we should keep running the
2788 inferior and not return to debugger. */
2790 if (trap_expected && stop_signal != TARGET_SIGNAL_TRAP)
2792 /* We took a signal (which we are supposed to pass through to
2793 the inferior, else we'd have done a break above) and we
2794 haven't yet gotten our trap. Simply continue. */
2795 resume (currently_stepping (ecs), stop_signal);
2799 /* Either the trap was not expected, but we are continuing
2800 anyway (the user asked that this signal be passed to the
2803 The signal was SIGTRAP, e.g. it was our signal, but we
2804 decided we should resume from it.
2806 We're going to run this baby now!
2808 Insert breakpoints now, unless we are trying to one-proceed
2809 past a breakpoint. */
2810 /* If we've just finished a special step resume and we don't
2811 want to hit a breakpoint, pull em out. */
2812 if (step_resume_breakpoint == NULL
2813 && through_sigtramp_breakpoint == NULL
2814 && ecs->remove_breakpoints_on_following_step)
2816 ecs->remove_breakpoints_on_following_step = 0;
2817 remove_breakpoints ();
2818 breakpoints_inserted = 0;
2820 else if (!breakpoints_inserted &&
2821 (through_sigtramp_breakpoint != NULL || !ecs->another_trap))
2823 breakpoints_failed = insert_breakpoints ();
2824 if (breakpoints_failed)
2826 stop_stepping (ecs);
2829 breakpoints_inserted = 1;
2832 trap_expected = ecs->another_trap;
2834 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
2835 specifies that such a signal should be delivered to the
2838 Typically, this would occure when a user is debugging a
2839 target monitor on a simulator: the target monitor sets a
2840 breakpoint; the simulator encounters this break-point and
2841 halts the simulation handing control to GDB; GDB, noteing
2842 that the break-point isn't valid, returns control back to the
2843 simulator; the simulator then delivers the hardware
2844 equivalent of a SIGNAL_TRAP to the program being debugged. */
2846 if (stop_signal == TARGET_SIGNAL_TRAP && !signal_program[stop_signal])
2847 stop_signal = TARGET_SIGNAL_0;
2849 #ifdef SHIFT_INST_REGS
2850 /* I'm not sure when this following segment applies. I do know,
2851 now, that we shouldn't rewrite the regs when we were stopped
2852 by a random signal from the inferior process. */
2853 /* FIXME: Shouldn't this be based on the valid bit of the SXIP?
2854 (this is only used on the 88k). */
2856 if (!bpstat_explains_signal (stop_bpstat)
2857 && (stop_signal != TARGET_SIGNAL_CHLD) && !stopped_by_random_signal)
2859 #endif /* SHIFT_INST_REGS */
2861 resume (currently_stepping (ecs), stop_signal);
2864 prepare_to_wait (ecs);
2867 /* This function normally comes after a resume, before
2868 handle_inferior_event exits. It takes care of any last bits of
2869 housekeeping, and sets the all-important wait_some_more flag. */
2872 prepare_to_wait (struct execution_control_state *ecs)
2874 if (ecs->infwait_state == infwait_normal_state)
2876 overlay_cache_invalid = 1;
2878 /* We have to invalidate the registers BEFORE calling
2879 target_wait because they can be loaded from the target while
2880 in target_wait. This makes remote debugging a bit more
2881 efficient for those targets that provide critical registers
2882 as part of their normal status mechanism. */
2884 registers_changed ();
2885 ecs->waiton_ptid = pid_to_ptid (-1);
2886 ecs->wp = &(ecs->ws);
2888 /* This is the old end of the while loop. Let everybody know we
2889 want to wait for the inferior some more and get called again
2891 ecs->wait_some_more = 1;
2894 /* Print why the inferior has stopped. We always print something when
2895 the inferior exits, or receives a signal. The rest of the cases are
2896 dealt with later on in normal_stop() and print_it_typical(). Ideally
2897 there should be a call to this function from handle_inferior_event()
2898 each time stop_stepping() is called.*/
2900 print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
2902 switch (stop_reason)
2905 /* We don't deal with these cases from handle_inferior_event()
2908 case END_STEPPING_RANGE:
2909 /* We are done with a step/next/si/ni command. */
2910 /* For now print nothing. */
2911 /* Print a message only if not in the middle of doing a "step n"
2912 operation for n > 1 */
2913 if (!step_multi || !stop_step)
2914 if (ui_out_is_mi_like_p (uiout))
2915 ui_out_field_string (uiout, "reason", "end-stepping-range");
2917 case BREAKPOINT_HIT:
2918 /* We found a breakpoint. */
2919 /* For now print nothing. */
2922 /* The inferior was terminated by a signal. */
2923 annotate_signalled ();
2924 if (ui_out_is_mi_like_p (uiout))
2925 ui_out_field_string (uiout, "reason", "exited-signalled");
2926 ui_out_text (uiout, "\nProgram terminated with signal ");
2927 annotate_signal_name ();
2928 ui_out_field_string (uiout, "signal-name",
2929 target_signal_to_name (stop_info));
2930 annotate_signal_name_end ();
2931 ui_out_text (uiout, ", ");
2932 annotate_signal_string ();
2933 ui_out_field_string (uiout, "signal-meaning",
2934 target_signal_to_string (stop_info));
2935 annotate_signal_string_end ();
2936 ui_out_text (uiout, ".\n");
2937 ui_out_text (uiout, "The program no longer exists.\n");
2940 /* The inferior program is finished. */
2941 annotate_exited (stop_info);
2944 if (ui_out_is_mi_like_p (uiout))
2945 ui_out_field_string (uiout, "reason", "exited");
2946 ui_out_text (uiout, "\nProgram exited with code ");
2947 ui_out_field_fmt (uiout, "exit-code", "0%o",
2948 (unsigned int) stop_info);
2949 ui_out_text (uiout, ".\n");
2953 if (ui_out_is_mi_like_p (uiout))
2954 ui_out_field_string (uiout, "reason", "exited-normally");
2955 ui_out_text (uiout, "\nProgram exited normally.\n");
2958 case SIGNAL_RECEIVED:
2959 /* Signal received. The signal table tells us to print about
2962 ui_out_text (uiout, "\nProgram received signal ");
2963 annotate_signal_name ();
2964 if (ui_out_is_mi_like_p (uiout))
2965 ui_out_field_string (uiout, "reason", "signal-received");
2966 ui_out_field_string (uiout, "signal-name",
2967 target_signal_to_name (stop_info));
2968 annotate_signal_name_end ();
2969 ui_out_text (uiout, ", ");
2970 annotate_signal_string ();
2971 ui_out_field_string (uiout, "signal-meaning",
2972 target_signal_to_string (stop_info));
2973 annotate_signal_string_end ();
2974 ui_out_text (uiout, ".\n");
2977 internal_error (__FILE__, __LINE__,
2978 "print_stop_reason: unrecognized enum value");
2984 /* Here to return control to GDB when the inferior stops for real.
2985 Print appropriate messages, remove breakpoints, give terminal our modes.
2987 STOP_PRINT_FRAME nonzero means print the executing frame
2988 (pc, function, args, file, line number and line text).
2989 BREAKPOINTS_FAILED nonzero means stop was due to error
2990 attempting to insert breakpoints. */
2995 /* As with the notification of thread events, we want to delay
2996 notifying the user that we've switched thread context until
2997 the inferior actually stops.
2999 (Note that there's no point in saying anything if the inferior
3001 if (!ptid_equal (previous_inferior_ptid, inferior_ptid)
3002 && target_has_execution)
3004 target_terminal_ours_for_output ();
3005 printf_filtered ("[Switching to %s]\n",
3006 target_pid_or_tid_to_str (inferior_ptid));
3007 previous_inferior_ptid = inferior_ptid;
3010 /* Make sure that the current_frame's pc is correct. This
3011 is a correction for setting up the frame info before doing
3012 DECR_PC_AFTER_BREAK */
3013 if (target_has_execution)
3014 /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
3015 DECR_PC_AFTER_BREAK, the program counter can change. Ask the
3016 frame code to check for this and sort out any resultant mess.
3017 DECR_PC_AFTER_BREAK needs to just go away. */
3018 deprecated_update_current_frame_pc_hack (read_pc ());
3020 if (target_has_execution && breakpoints_inserted)
3022 if (remove_breakpoints ())
3024 target_terminal_ours_for_output ();
3025 printf_filtered ("Cannot remove breakpoints because ");
3026 printf_filtered ("program is no longer writable.\n");
3027 printf_filtered ("It might be running in another process.\n");
3028 printf_filtered ("Further execution is probably impossible.\n");
3031 breakpoints_inserted = 0;
3033 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3034 Delete any breakpoint that is to be deleted at the next stop. */
3036 breakpoint_auto_delete (stop_bpstat);
3038 /* If an auto-display called a function and that got a signal,
3039 delete that auto-display to avoid an infinite recursion. */
3041 if (stopped_by_random_signal)
3042 disable_current_display ();
3044 /* Don't print a message if in the middle of doing a "step n"
3045 operation for n > 1 */
3046 if (step_multi && stop_step)
3049 target_terminal_ours ();
3051 /* Look up the hook_stop and run it (CLI internally handles problem
3052 of stop_command's pre-hook not existing). */
3054 catch_errors (hook_stop_stub, stop_command,
3055 "Error while running hook_stop:\n", RETURN_MASK_ALL);
3057 if (!target_has_stack)
3063 /* Select innermost stack frame - i.e., current frame is frame 0,
3064 and current location is based on that.
3065 Don't do this on return from a stack dummy routine,
3066 or if the program has exited. */
3068 if (!stop_stack_dummy)
3070 select_frame (get_current_frame ());
3072 /* Print current location without a level number, if
3073 we have changed functions or hit a breakpoint.
3074 Print source line if we have one.
3075 bpstat_print() contains the logic deciding in detail
3076 what to print, based on the event(s) that just occurred. */
3078 if (stop_print_frame && deprecated_selected_frame)
3082 int do_frame_printing = 1;
3084 bpstat_ret = bpstat_print (stop_bpstat);
3088 /* FIXME: cagney/2002-12-01: Given that a frame ID does
3089 (or should) carry around the function and does (or
3090 should) use that when doing a frame comparison. */
3092 && frame_id_eq (step_frame_id,
3093 get_frame_id (get_current_frame ()))
3094 && step_start_function == find_pc_function (stop_pc))
3095 source_flag = SRC_LINE; /* finished step, just print source line */
3097 source_flag = SRC_AND_LOC; /* print location and source line */
3099 case PRINT_SRC_AND_LOC:
3100 source_flag = SRC_AND_LOC; /* print location and source line */
3102 case PRINT_SRC_ONLY:
3103 source_flag = SRC_LINE;
3106 source_flag = SRC_LINE; /* something bogus */
3107 do_frame_printing = 0;
3110 internal_error (__FILE__, __LINE__, "Unknown value.");
3112 /* For mi, have the same behavior every time we stop:
3113 print everything but the source line. */
3114 if (ui_out_is_mi_like_p (uiout))
3115 source_flag = LOC_AND_ADDRESS;
3117 if (ui_out_is_mi_like_p (uiout))
3118 ui_out_field_int (uiout, "thread-id",
3119 pid_to_thread_id (inferior_ptid));
3120 /* The behavior of this routine with respect to the source
3122 SRC_LINE: Print only source line
3123 LOCATION: Print only location
3124 SRC_AND_LOC: Print location and source line */
3125 if (do_frame_printing)
3126 show_and_print_stack_frame (deprecated_selected_frame, -1, source_flag);
3128 /* Display the auto-display expressions. */
3133 /* Save the function value return registers, if we care.
3134 We might be about to restore their previous contents. */
3135 if (proceed_to_finish)
3136 /* NB: The copy goes through to the target picking up the value of
3137 all the registers. */
3138 regcache_cpy (stop_registers, current_regcache);
3140 if (stop_stack_dummy)
3142 /* Pop the empty frame that contains the stack dummy.
3143 POP_FRAME ends with a setting of the current frame, so we
3144 can use that next. */
3146 /* Set stop_pc to what it was before we called the function.
3147 Can't rely on restore_inferior_status because that only gets
3148 called if we don't stop in the called function. */
3149 stop_pc = read_pc ();
3150 select_frame (get_current_frame ());
3154 annotate_stopped ();
3158 hook_stop_stub (void *cmd)
3160 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
3165 signal_stop_state (int signo)
3167 return signal_stop[signo];
3171 signal_print_state (int signo)
3173 return signal_print[signo];
3177 signal_pass_state (int signo)
3179 return signal_program[signo];
3183 signal_stop_update (int signo, int state)
3185 int ret = signal_stop[signo];
3186 signal_stop[signo] = state;
3191 signal_print_update (int signo, int state)
3193 int ret = signal_print[signo];
3194 signal_print[signo] = state;
3199 signal_pass_update (int signo, int state)
3201 int ret = signal_program[signo];
3202 signal_program[signo] = state;
3207 sig_print_header (void)
3210 Signal Stop\tPrint\tPass to program\tDescription\n");
3214 sig_print_info (enum target_signal oursig)
3216 char *name = target_signal_to_name (oursig);
3217 int name_padding = 13 - strlen (name);
3219 if (name_padding <= 0)
3222 printf_filtered ("%s", name);
3223 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
3224 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
3225 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
3226 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
3227 printf_filtered ("%s\n", target_signal_to_string (oursig));
3230 /* Specify how various signals in the inferior should be handled. */
3233 handle_command (char *args, int from_tty)
3236 int digits, wordlen;
3237 int sigfirst, signum, siglast;
3238 enum target_signal oursig;
3241 unsigned char *sigs;
3242 struct cleanup *old_chain;
3246 error_no_arg ("signal to handle");
3249 /* Allocate and zero an array of flags for which signals to handle. */
3251 nsigs = (int) TARGET_SIGNAL_LAST;
3252 sigs = (unsigned char *) alloca (nsigs);
3253 memset (sigs, 0, nsigs);
3255 /* Break the command line up into args. */
3257 argv = buildargv (args);
3262 old_chain = make_cleanup_freeargv (argv);
3264 /* Walk through the args, looking for signal oursigs, signal names, and
3265 actions. Signal numbers and signal names may be interspersed with
3266 actions, with the actions being performed for all signals cumulatively
3267 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
3269 while (*argv != NULL)
3271 wordlen = strlen (*argv);
3272 for (digits = 0; isdigit ((*argv)[digits]); digits++)
3276 sigfirst = siglast = -1;
3278 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
3280 /* Apply action to all signals except those used by the
3281 debugger. Silently skip those. */
3284 siglast = nsigs - 1;
3286 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
3288 SET_SIGS (nsigs, sigs, signal_stop);
3289 SET_SIGS (nsigs, sigs, signal_print);
3291 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
3293 UNSET_SIGS (nsigs, sigs, signal_program);
3295 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
3297 SET_SIGS (nsigs, sigs, signal_print);
3299 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
3301 SET_SIGS (nsigs, sigs, signal_program);
3303 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
3305 UNSET_SIGS (nsigs, sigs, signal_stop);
3307 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
3309 SET_SIGS (nsigs, sigs, signal_program);
3311 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
3313 UNSET_SIGS (nsigs, sigs, signal_print);
3314 UNSET_SIGS (nsigs, sigs, signal_stop);
3316 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
3318 UNSET_SIGS (nsigs, sigs, signal_program);
3320 else if (digits > 0)
3322 /* It is numeric. The numeric signal refers to our own
3323 internal signal numbering from target.h, not to host/target
3324 signal number. This is a feature; users really should be
3325 using symbolic names anyway, and the common ones like
3326 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
3328 sigfirst = siglast = (int)
3329 target_signal_from_command (atoi (*argv));
3330 if ((*argv)[digits] == '-')
3333 target_signal_from_command (atoi ((*argv) + digits + 1));
3335 if (sigfirst > siglast)
3337 /* Bet he didn't figure we'd think of this case... */
3345 oursig = target_signal_from_name (*argv);
3346 if (oursig != TARGET_SIGNAL_UNKNOWN)
3348 sigfirst = siglast = (int) oursig;
3352 /* Not a number and not a recognized flag word => complain. */
3353 error ("Unrecognized or ambiguous flag word: \"%s\".", *argv);
3357 /* If any signal numbers or symbol names were found, set flags for
3358 which signals to apply actions to. */
3360 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
3362 switch ((enum target_signal) signum)
3364 case TARGET_SIGNAL_TRAP:
3365 case TARGET_SIGNAL_INT:
3366 if (!allsigs && !sigs[signum])
3368 if (query ("%s is used by the debugger.\n\
3369 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal) signum)))
3375 printf_unfiltered ("Not confirmed, unchanged.\n");
3376 gdb_flush (gdb_stdout);
3380 case TARGET_SIGNAL_0:
3381 case TARGET_SIGNAL_DEFAULT:
3382 case TARGET_SIGNAL_UNKNOWN:
3383 /* Make sure that "all" doesn't print these. */
3394 target_notice_signals (inferior_ptid);
3398 /* Show the results. */
3399 sig_print_header ();
3400 for (signum = 0; signum < nsigs; signum++)
3404 sig_print_info (signum);
3409 do_cleanups (old_chain);
3413 xdb_handle_command (char *args, int from_tty)
3416 struct cleanup *old_chain;
3418 /* Break the command line up into args. */
3420 argv = buildargv (args);
3425 old_chain = make_cleanup_freeargv (argv);
3426 if (argv[1] != (char *) NULL)
3431 bufLen = strlen (argv[0]) + 20;
3432 argBuf = (char *) xmalloc (bufLen);
3436 enum target_signal oursig;
3438 oursig = target_signal_from_name (argv[0]);
3439 memset (argBuf, 0, bufLen);
3440 if (strcmp (argv[1], "Q") == 0)
3441 sprintf (argBuf, "%s %s", argv[0], "noprint");
3444 if (strcmp (argv[1], "s") == 0)
3446 if (!signal_stop[oursig])
3447 sprintf (argBuf, "%s %s", argv[0], "stop");
3449 sprintf (argBuf, "%s %s", argv[0], "nostop");
3451 else if (strcmp (argv[1], "i") == 0)
3453 if (!signal_program[oursig])
3454 sprintf (argBuf, "%s %s", argv[0], "pass");
3456 sprintf (argBuf, "%s %s", argv[0], "nopass");
3458 else if (strcmp (argv[1], "r") == 0)
3460 if (!signal_print[oursig])
3461 sprintf (argBuf, "%s %s", argv[0], "print");
3463 sprintf (argBuf, "%s %s", argv[0], "noprint");
3469 handle_command (argBuf, from_tty);
3471 printf_filtered ("Invalid signal handling flag.\n");
3476 do_cleanups (old_chain);
3479 /* Print current contents of the tables set by the handle command.
3480 It is possible we should just be printing signals actually used
3481 by the current target (but for things to work right when switching
3482 targets, all signals should be in the signal tables). */
3485 signals_info (char *signum_exp, int from_tty)
3487 enum target_signal oursig;
3488 sig_print_header ();
3492 /* First see if this is a symbol name. */
3493 oursig = target_signal_from_name (signum_exp);
3494 if (oursig == TARGET_SIGNAL_UNKNOWN)
3496 /* No, try numeric. */
3498 target_signal_from_command (parse_and_eval_long (signum_exp));
3500 sig_print_info (oursig);
3504 printf_filtered ("\n");
3505 /* These ugly casts brought to you by the native VAX compiler. */
3506 for (oursig = TARGET_SIGNAL_FIRST;
3507 (int) oursig < (int) TARGET_SIGNAL_LAST;
3508 oursig = (enum target_signal) ((int) oursig + 1))
3512 if (oursig != TARGET_SIGNAL_UNKNOWN
3513 && oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0)
3514 sig_print_info (oursig);
3517 printf_filtered ("\nUse the \"handle\" command to change these tables.\n");
3520 struct inferior_status
3522 enum target_signal stop_signal;
3526 int stop_stack_dummy;
3527 int stopped_by_random_signal;
3529 CORE_ADDR step_range_start;
3530 CORE_ADDR step_range_end;
3531 struct frame_id step_frame_id;
3532 enum step_over_calls_kind step_over_calls;
3533 CORE_ADDR step_resume_break_address;
3534 int stop_after_trap;
3535 int stop_soon_quietly;
3536 struct regcache *stop_registers;
3538 /* These are here because if call_function_by_hand has written some
3539 registers and then decides to call error(), we better not have changed
3541 struct regcache *registers;
3543 /* A frame unique identifier. */
3544 struct frame_id selected_frame_id;
3546 int breakpoint_proceeded;
3547 int restore_stack_info;
3548 int proceed_to_finish;
3552 write_inferior_status_register (struct inferior_status *inf_status, int regno,
3555 int size = REGISTER_RAW_SIZE (regno);
3556 void *buf = alloca (size);
3557 store_signed_integer (buf, size, val);
3558 regcache_raw_write (inf_status->registers, regno, buf);
3561 /* Save all of the information associated with the inferior<==>gdb
3562 connection. INF_STATUS is a pointer to a "struct inferior_status"
3563 (defined in inferior.h). */
3565 struct inferior_status *
3566 save_inferior_status (int restore_stack_info)
3568 struct inferior_status *inf_status = XMALLOC (struct inferior_status);
3570 inf_status->stop_signal = stop_signal;
3571 inf_status->stop_pc = stop_pc;
3572 inf_status->stop_step = stop_step;
3573 inf_status->stop_stack_dummy = stop_stack_dummy;
3574 inf_status->stopped_by_random_signal = stopped_by_random_signal;
3575 inf_status->trap_expected = trap_expected;
3576 inf_status->step_range_start = step_range_start;
3577 inf_status->step_range_end = step_range_end;
3578 inf_status->step_frame_id = step_frame_id;
3579 inf_status->step_over_calls = step_over_calls;
3580 inf_status->stop_after_trap = stop_after_trap;
3581 inf_status->stop_soon_quietly = stop_soon_quietly;
3582 /* Save original bpstat chain here; replace it with copy of chain.
3583 If caller's caller is walking the chain, they'll be happier if we
3584 hand them back the original chain when restore_inferior_status is
3586 inf_status->stop_bpstat = stop_bpstat;
3587 stop_bpstat = bpstat_copy (stop_bpstat);
3588 inf_status->breakpoint_proceeded = breakpoint_proceeded;
3589 inf_status->restore_stack_info = restore_stack_info;
3590 inf_status->proceed_to_finish = proceed_to_finish;
3592 inf_status->stop_registers = regcache_dup_no_passthrough (stop_registers);
3594 inf_status->registers = regcache_dup (current_regcache);
3596 inf_status->selected_frame_id = get_frame_id (deprecated_selected_frame);
3601 restore_selected_frame (void *args)
3603 struct frame_id *fid = (struct frame_id *) args;
3604 struct frame_info *frame;
3606 frame = frame_find_by_id (*fid);
3608 /* If inf_status->selected_frame_id is NULL, there was no previously
3612 warning ("Unable to restore previously selected frame.\n");
3616 select_frame (frame);
3622 restore_inferior_status (struct inferior_status *inf_status)
3624 stop_signal = inf_status->stop_signal;
3625 stop_pc = inf_status->stop_pc;
3626 stop_step = inf_status->stop_step;
3627 stop_stack_dummy = inf_status->stop_stack_dummy;
3628 stopped_by_random_signal = inf_status->stopped_by_random_signal;
3629 trap_expected = inf_status->trap_expected;
3630 step_range_start = inf_status->step_range_start;
3631 step_range_end = inf_status->step_range_end;
3632 step_frame_id = inf_status->step_frame_id;
3633 step_over_calls = inf_status->step_over_calls;
3634 stop_after_trap = inf_status->stop_after_trap;
3635 stop_soon_quietly = inf_status->stop_soon_quietly;
3636 bpstat_clear (&stop_bpstat);
3637 stop_bpstat = inf_status->stop_bpstat;
3638 breakpoint_proceeded = inf_status->breakpoint_proceeded;
3639 proceed_to_finish = inf_status->proceed_to_finish;
3641 /* FIXME: Is the restore of stop_registers always needed. */
3642 regcache_xfree (stop_registers);
3643 stop_registers = inf_status->stop_registers;
3645 /* The inferior can be gone if the user types "print exit(0)"
3646 (and perhaps other times). */
3647 if (target_has_execution)
3648 /* NB: The register write goes through to the target. */
3649 regcache_cpy (current_regcache, inf_status->registers);
3650 regcache_xfree (inf_status->registers);
3652 /* FIXME: If we are being called after stopping in a function which
3653 is called from gdb, we should not be trying to restore the
3654 selected frame; it just prints a spurious error message (The
3655 message is useful, however, in detecting bugs in gdb (like if gdb
3656 clobbers the stack)). In fact, should we be restoring the
3657 inferior status at all in that case? . */
3659 if (target_has_stack && inf_status->restore_stack_info)
3661 /* The point of catch_errors is that if the stack is clobbered,
3662 walking the stack might encounter a garbage pointer and
3663 error() trying to dereference it. */
3665 (restore_selected_frame, &inf_status->selected_frame_id,
3666 "Unable to restore previously selected frame:\n",
3667 RETURN_MASK_ERROR) == 0)
3668 /* Error in restoring the selected frame. Select the innermost
3670 select_frame (get_current_frame ());
3678 do_restore_inferior_status_cleanup (void *sts)
3680 restore_inferior_status (sts);
3684 make_cleanup_restore_inferior_status (struct inferior_status *inf_status)
3686 return make_cleanup (do_restore_inferior_status_cleanup, inf_status);
3690 discard_inferior_status (struct inferior_status *inf_status)
3692 /* See save_inferior_status for info on stop_bpstat. */
3693 bpstat_clear (&inf_status->stop_bpstat);
3694 regcache_xfree (inf_status->registers);
3695 regcache_xfree (inf_status->stop_registers);
3700 inferior_has_forked (int pid, int *child_pid)
3702 struct target_waitstatus last;
3705 get_last_target_status (&last_ptid, &last);
3707 if (last.kind != TARGET_WAITKIND_FORKED)
3710 if (ptid_get_pid (last_ptid) != pid)
3713 *child_pid = last.value.related_pid;
3718 inferior_has_vforked (int pid, int *child_pid)
3720 struct target_waitstatus last;
3723 get_last_target_status (&last_ptid, &last);
3725 if (last.kind != TARGET_WAITKIND_VFORKED)
3728 if (ptid_get_pid (last_ptid) != pid)
3731 *child_pid = last.value.related_pid;
3736 inferior_has_execd (int pid, char **execd_pathname)
3738 struct target_waitstatus last;
3741 get_last_target_status (&last_ptid, &last);
3743 if (last.kind != TARGET_WAITKIND_EXECD)
3746 if (ptid_get_pid (last_ptid) != pid)
3749 *execd_pathname = xstrdup (last.value.execd_pathname);
3753 /* Oft used ptids */
3755 ptid_t minus_one_ptid;
3757 /* Create a ptid given the necessary PID, LWP, and TID components. */
3760 ptid_build (int pid, long lwp, long tid)
3770 /* Create a ptid from just a pid. */
3773 pid_to_ptid (int pid)
3775 return ptid_build (pid, 0, 0);
3778 /* Fetch the pid (process id) component from a ptid. */
3781 ptid_get_pid (ptid_t ptid)
3786 /* Fetch the lwp (lightweight process) component from a ptid. */
3789 ptid_get_lwp (ptid_t ptid)
3794 /* Fetch the tid (thread id) component from a ptid. */
3797 ptid_get_tid (ptid_t ptid)
3802 /* ptid_equal() is used to test equality of two ptids. */
3805 ptid_equal (ptid_t ptid1, ptid_t ptid2)
3807 return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp
3808 && ptid1.tid == ptid2.tid);
3811 /* restore_inferior_ptid() will be used by the cleanup machinery
3812 to restore the inferior_ptid value saved in a call to
3813 save_inferior_ptid(). */
3816 restore_inferior_ptid (void *arg)
3818 ptid_t *saved_ptid_ptr = arg;
3819 inferior_ptid = *saved_ptid_ptr;
3823 /* Save the value of inferior_ptid so that it may be restored by a
3824 later call to do_cleanups(). Returns the struct cleanup pointer
3825 needed for later doing the cleanup. */
3828 save_inferior_ptid (void)
3830 ptid_t *saved_ptid_ptr;
3832 saved_ptid_ptr = xmalloc (sizeof (ptid_t));
3833 *saved_ptid_ptr = inferior_ptid;
3834 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
3841 stop_registers = regcache_xmalloc (current_gdbarch);
3845 _initialize_infrun (void)
3848 register int numsigs;
3849 struct cmd_list_element *c;
3851 register_gdbarch_swap (&stop_registers, sizeof (stop_registers), NULL);
3852 register_gdbarch_swap (NULL, 0, build_infrun);
3854 add_info ("signals", signals_info,
3855 "What debugger does when program gets various signals.\n\
3856 Specify a signal as argument to print info on that signal only.");
3857 add_info_alias ("handle", "signals", 0);
3859 add_com ("handle", class_run, handle_command,
3860 concat ("Specify how to handle a signal.\n\
3861 Args are signals and actions to apply to those signals.\n\
3862 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
3863 from 1-15 are allowed for compatibility with old versions of GDB.\n\
3864 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
3865 The special arg \"all\" is recognized to mean all signals except those\n\
3866 used by the debugger, typically SIGTRAP and SIGINT.\n", "Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
3867 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
3868 Stop means reenter debugger if this signal happens (implies print).\n\
3869 Print means print a message if this signal happens.\n\
3870 Pass means let program see this signal; otherwise program doesn't know.\n\
3871 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
3872 Pass and Stop may be combined.", NULL));
3875 add_com ("lz", class_info, signals_info,
3876 "What debugger does when program gets various signals.\n\
3877 Specify a signal as argument to print info on that signal only.");
3878 add_com ("z", class_run, xdb_handle_command,
3879 concat ("Specify how to handle a signal.\n\
3880 Args are signals and actions to apply to those signals.\n\
3881 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
3882 from 1-15 are allowed for compatibility with old versions of GDB.\n\
3883 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
3884 The special arg \"all\" is recognized to mean all signals except those\n\
3885 used by the debugger, typically SIGTRAP and SIGINT.\n", "Recognized actions include \"s\" (toggles between stop and nostop), \n\
3886 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
3887 nopass), \"Q\" (noprint)\n\
3888 Stop means reenter debugger if this signal happens (implies print).\n\
3889 Print means print a message if this signal happens.\n\
3890 Pass means let program see this signal; otherwise program doesn't know.\n\
3891 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
3892 Pass and Stop may be combined.", NULL));
3897 add_cmd ("stop", class_obscure, not_just_help_class_command, "There is no `stop' command, but you can set a hook on `stop'.\n\
3898 This allows you to set a list of commands to be run each time execution\n\
3899 of the program stops.", &cmdlist);
3901 numsigs = (int) TARGET_SIGNAL_LAST;
3902 signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
3903 signal_print = (unsigned char *)
3904 xmalloc (sizeof (signal_print[0]) * numsigs);
3905 signal_program = (unsigned char *)
3906 xmalloc (sizeof (signal_program[0]) * numsigs);
3907 for (i = 0; i < numsigs; i++)
3910 signal_print[i] = 1;
3911 signal_program[i] = 1;
3914 /* Signals caused by debugger's own actions
3915 should not be given to the program afterwards. */
3916 signal_program[TARGET_SIGNAL_TRAP] = 0;
3917 signal_program[TARGET_SIGNAL_INT] = 0;
3919 /* Signals that are not errors should not normally enter the debugger. */
3920 signal_stop[TARGET_SIGNAL_ALRM] = 0;
3921 signal_print[TARGET_SIGNAL_ALRM] = 0;
3922 signal_stop[TARGET_SIGNAL_VTALRM] = 0;
3923 signal_print[TARGET_SIGNAL_VTALRM] = 0;
3924 signal_stop[TARGET_SIGNAL_PROF] = 0;
3925 signal_print[TARGET_SIGNAL_PROF] = 0;
3926 signal_stop[TARGET_SIGNAL_CHLD] = 0;
3927 signal_print[TARGET_SIGNAL_CHLD] = 0;
3928 signal_stop[TARGET_SIGNAL_IO] = 0;
3929 signal_print[TARGET_SIGNAL_IO] = 0;
3930 signal_stop[TARGET_SIGNAL_POLL] = 0;
3931 signal_print[TARGET_SIGNAL_POLL] = 0;
3932 signal_stop[TARGET_SIGNAL_URG] = 0;
3933 signal_print[TARGET_SIGNAL_URG] = 0;
3934 signal_stop[TARGET_SIGNAL_WINCH] = 0;
3935 signal_print[TARGET_SIGNAL_WINCH] = 0;
3937 /* These signals are used internally by user-level thread
3938 implementations. (See signal(5) on Solaris.) Like the above
3939 signals, a healthy program receives and handles them as part of
3940 its normal operation. */
3941 signal_stop[TARGET_SIGNAL_LWP] = 0;
3942 signal_print[TARGET_SIGNAL_LWP] = 0;
3943 signal_stop[TARGET_SIGNAL_WAITING] = 0;
3944 signal_print[TARGET_SIGNAL_WAITING] = 0;
3945 signal_stop[TARGET_SIGNAL_CANCEL] = 0;
3946 signal_print[TARGET_SIGNAL_CANCEL] = 0;
3950 (add_set_cmd ("stop-on-solib-events", class_support, var_zinteger,
3951 (char *) &stop_on_solib_events,
3952 "Set stopping for shared library events.\n\
3953 If nonzero, gdb will give control to the user when the dynamic linker\n\
3954 notifies gdb of shared library events. The most common event of interest\n\
3955 to the user would be loading/unloading of a new library.\n", &setlist), &showlist);
3958 c = add_set_enum_cmd ("follow-fork-mode",
3960 follow_fork_mode_kind_names, &follow_fork_mode_string,
3961 /* ??rehrauer: The "both" option is broken, by what may be a 10.20
3962 kernel problem. It's also not terribly useful without a GUI to
3963 help the user drive two debuggers. So for now, I'm disabling
3964 the "both" option. */
3965 /* "Set debugger response to a program call of fork \
3967 A fork or vfork creates a new process. follow-fork-mode can be:\n\
3968 parent - the original process is debugged after a fork\n\
3969 child - the new process is debugged after a fork\n\
3970 both - both the parent and child are debugged after a fork\n\
3971 ask - the debugger will ask for one of the above choices\n\
3972 For \"both\", another copy of the debugger will be started to follow\n\
3973 the new child process. The original debugger will continue to follow\n\
3974 the original parent process. To distinguish their prompts, the\n\
3975 debugger copy's prompt will be changed.\n\
3976 For \"parent\" or \"child\", the unfollowed process will run free.\n\
3977 By default, the debugger will follow the parent process.",
3979 "Set debugger response to a program call of fork \
3981 A fork or vfork creates a new process. follow-fork-mode can be:\n\
3982 parent - the original process is debugged after a fork\n\
3983 child - the new process is debugged after a fork\n\
3984 ask - the debugger will ask for one of the above choices\n\
3985 For \"parent\" or \"child\", the unfollowed process will run free.\n\
3986 By default, the debugger will follow the parent process.", &setlist);
3987 add_show_from_set (c, &showlist);
3989 c = add_set_enum_cmd ("scheduler-locking", class_run, scheduler_enums, /* array of string names */
3990 &scheduler_mode, /* current mode */
3991 "Set mode for locking scheduler during execution.\n\
3992 off == no locking (threads may preempt at any time)\n\
3993 on == full locking (no thread except the current thread may run)\n\
3994 step == scheduler locked during every single-step operation.\n\
3995 In this mode, no other thread may run during a step command.\n\
3996 Other threads may run while stepping over a function call ('next').", &setlist);
3998 set_cmd_sfunc (c, set_schedlock_func); /* traps on target vector */
3999 add_show_from_set (c, &showlist);
4001 c = add_set_cmd ("step-mode", class_run,
4002 var_boolean, (char *) &step_stop_if_no_debug,
4003 "Set mode of the step operation. When set, doing a step over a\n\
4004 function without debug line information will stop at the first\n\
4005 instruction of that function. Otherwise, the function is skipped and\n\
4006 the step command stops at a different source line.", &setlist);
4007 add_show_from_set (c, &showlist);
4009 /* ptid initializations */
4010 null_ptid = ptid_build (0, 0, 0);
4011 minus_one_ptid = ptid_build (-1, 0, 0);
4012 inferior_ptid = null_ptid;
4013 target_last_wait_ptid = minus_one_ptid;