1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
5 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
6 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
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 3 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, see <http://www.gnu.org/licenses/>. */
24 #include "gdb_string.h"
29 #include "exceptions.h"
30 #include "breakpoint.h"
34 #include "cli/cli-script.h"
36 #include "gdbthread.h"
48 #include "dictionary.h"
50 #include "gdb_assert.h"
51 #include "mi/mi-common.h"
52 #include "event-top.h"
54 #include "inline-frame.h"
56 #include "tracepoint.h"
58 /* Prototypes for local functions */
60 static void signals_info (char *, int);
62 static void handle_command (char *, int);
64 static void sig_print_info (enum target_signal
);
66 static void sig_print_header (void);
68 static void resume_cleanups (void *);
70 static int hook_stop_stub (void *);
72 static int restore_selected_frame (void *);
74 static int follow_fork (void);
76 static void set_schedlock_func (char *args
, int from_tty
,
77 struct cmd_list_element
*c
);
79 static int currently_stepping (struct thread_info
*tp
);
81 static int currently_stepping_or_nexting_callback (struct thread_info
*tp
,
84 static void xdb_handle_command (char *args
, int from_tty
);
86 static int prepare_to_proceed (int);
88 static void print_exited_reason (int exitstatus
);
90 static void print_signal_exited_reason (enum target_signal siggnal
);
92 static void print_no_history_reason (void);
94 static void print_signal_received_reason (enum target_signal siggnal
);
96 static void print_end_stepping_range_reason (void);
98 void _initialize_infrun (void);
100 void nullify_last_target_wait_ptid (void);
102 static void insert_step_resume_breakpoint_at_frame (struct frame_info
*);
104 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
106 static void insert_step_resume_breakpoint_at_sal (struct gdbarch
*,
107 struct symtab_and_line
,
110 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
112 /* When set, stop the 'step' command if we enter a function which has
113 no line number information. The normal behavior is that we step
114 over such function. */
115 int step_stop_if_no_debug
= 0;
117 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
118 struct cmd_list_element
*c
, const char *value
)
120 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
123 /* In asynchronous mode, but simulating synchronous execution. */
125 int sync_execution
= 0;
127 /* wait_for_inferior and normal_stop use this to notify the user
128 when the inferior stopped in a different thread than it had been
131 static ptid_t previous_inferior_ptid
;
133 /* Default behavior is to detach newly forked processes (legacy). */
136 int debug_displaced
= 0;
138 show_debug_displaced (struct ui_file
*file
, int from_tty
,
139 struct cmd_list_element
*c
, const char *value
)
141 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
144 int debug_infrun
= 0;
146 show_debug_infrun (struct ui_file
*file
, int from_tty
,
147 struct cmd_list_element
*c
, const char *value
)
149 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
152 /* If the program uses ELF-style shared libraries, then calls to
153 functions in shared libraries go through stubs, which live in a
154 table called the PLT (Procedure Linkage Table). The first time the
155 function is called, the stub sends control to the dynamic linker,
156 which looks up the function's real address, patches the stub so
157 that future calls will go directly to the function, and then passes
158 control to the function.
160 If we are stepping at the source level, we don't want to see any of
161 this --- we just want to skip over the stub and the dynamic linker.
162 The simple approach is to single-step until control leaves the
165 However, on some systems (e.g., Red Hat's 5.2 distribution) the
166 dynamic linker calls functions in the shared C library, so you
167 can't tell from the PC alone whether the dynamic linker is still
168 running. In this case, we use a step-resume breakpoint to get us
169 past the dynamic linker, as if we were using "next" to step over a
172 in_solib_dynsym_resolve_code() says whether we're in the dynamic
173 linker code or not. Normally, this means we single-step. However,
174 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
175 address where we can place a step-resume breakpoint to get past the
176 linker's symbol resolution function.
178 in_solib_dynsym_resolve_code() can generally be implemented in a
179 pretty portable way, by comparing the PC against the address ranges
180 of the dynamic linker's sections.
182 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
183 it depends on internal details of the dynamic linker. It's usually
184 not too hard to figure out where to put a breakpoint, but it
185 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
186 sanity checking. If it can't figure things out, returning zero and
187 getting the (possibly confusing) stepping behavior is better than
188 signalling an error, which will obscure the change in the
191 /* This function returns TRUE if pc is the address of an instruction
192 that lies within the dynamic linker (such as the event hook, or the
195 This function must be used only when a dynamic linker event has
196 been caught, and the inferior is being stepped out of the hook, or
197 undefined results are guaranteed. */
199 #ifndef SOLIB_IN_DYNAMIC_LINKER
200 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
203 /* "Observer mode" is somewhat like a more extreme version of
204 non-stop, in which all GDB operations that might affect the
205 target's execution have been disabled. */
207 static int non_stop_1
= 0;
209 int observer_mode
= 0;
210 static int observer_mode_1
= 0;
213 set_observer_mode (char *args
, int from_tty
,
214 struct cmd_list_element
*c
)
216 extern int pagination_enabled
;
218 if (target_has_execution
)
220 observer_mode_1
= observer_mode
;
221 error (_("Cannot change this setting while the inferior is running."));
224 observer_mode
= observer_mode_1
;
226 may_write_registers
= !observer_mode
;
227 may_write_memory
= !observer_mode
;
228 may_insert_breakpoints
= !observer_mode
;
229 may_insert_tracepoints
= !observer_mode
;
230 /* We can insert fast tracepoints in or out of observer mode,
231 but enable them if we're going into this mode. */
233 may_insert_fast_tracepoints
= 1;
234 may_stop
= !observer_mode
;
235 update_target_permissions ();
237 /* Going *into* observer mode we must force non-stop, then
238 going out we leave it that way. */
241 target_async_permitted
= 1;
242 pagination_enabled
= 0;
243 non_stop
= non_stop_1
= 1;
247 printf_filtered (_("Observer mode is now %s.\n"),
248 (observer_mode
? "on" : "off"));
252 show_observer_mode (struct ui_file
*file
, int from_tty
,
253 struct cmd_list_element
*c
, const char *value
)
255 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
258 /* This updates the value of observer mode based on changes in
259 permissions. Note that we are deliberately ignoring the values of
260 may-write-registers and may-write-memory, since the user may have
261 reason to enable these during a session, for instance to turn on a
262 debugging-related global. */
265 update_observer_mode (void)
269 newval
= (!may_insert_breakpoints
270 && !may_insert_tracepoints
271 && may_insert_fast_tracepoints
275 /* Let the user know if things change. */
276 if (newval
!= observer_mode
)
277 printf_filtered (_("Observer mode is now %s.\n"),
278 (newval
? "on" : "off"));
280 observer_mode
= observer_mode_1
= newval
;
283 /* Tables of how to react to signals; the user sets them. */
285 static unsigned char *signal_stop
;
286 static unsigned char *signal_print
;
287 static unsigned char *signal_program
;
289 /* Table of signals that the target may silently handle.
290 This is automatically determined from the flags above,
291 and simply cached here. */
292 static unsigned char *signal_pass
;
294 #define SET_SIGS(nsigs,sigs,flags) \
296 int signum = (nsigs); \
297 while (signum-- > 0) \
298 if ((sigs)[signum]) \
299 (flags)[signum] = 1; \
302 #define UNSET_SIGS(nsigs,sigs,flags) \
304 int signum = (nsigs); \
305 while (signum-- > 0) \
306 if ((sigs)[signum]) \
307 (flags)[signum] = 0; \
310 /* Value to pass to target_resume() to cause all threads to resume. */
312 #define RESUME_ALL minus_one_ptid
314 /* Command list pointer for the "stop" placeholder. */
316 static struct cmd_list_element
*stop_command
;
318 /* Function inferior was in as of last step command. */
320 static struct symbol
*step_start_function
;
322 /* Nonzero if we want to give control to the user when we're notified
323 of shared library events by the dynamic linker. */
324 int stop_on_solib_events
;
326 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
327 struct cmd_list_element
*c
, const char *value
)
329 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
333 /* Nonzero means expecting a trace trap
334 and should stop the inferior and return silently when it happens. */
338 /* Save register contents here when executing a "finish" command or are
339 about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
340 Thus this contains the return value from the called function (assuming
341 values are returned in a register). */
343 struct regcache
*stop_registers
;
345 /* Nonzero after stop if current stack frame should be printed. */
347 static int stop_print_frame
;
349 /* This is a cached copy of the pid/waitstatus of the last event
350 returned by target_wait()/deprecated_target_wait_hook(). This
351 information is returned by get_last_target_status(). */
352 static ptid_t target_last_wait_ptid
;
353 static struct target_waitstatus target_last_waitstatus
;
355 static void context_switch (ptid_t ptid
);
357 void init_thread_stepping_state (struct thread_info
*tss
);
359 void init_infwait_state (void);
361 static const char follow_fork_mode_child
[] = "child";
362 static const char follow_fork_mode_parent
[] = "parent";
364 static const char *follow_fork_mode_kind_names
[] = {
365 follow_fork_mode_child
,
366 follow_fork_mode_parent
,
370 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
372 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
373 struct cmd_list_element
*c
, const char *value
)
375 fprintf_filtered (file
,
376 _("Debugger response to a program "
377 "call of fork or vfork is \"%s\".\n"),
382 /* Tell the target to follow the fork we're stopped at. Returns true
383 if the inferior should be resumed; false, if the target for some
384 reason decided it's best not to resume. */
389 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
390 int should_resume
= 1;
391 struct thread_info
*tp
;
393 /* Copy user stepping state to the new inferior thread. FIXME: the
394 followed fork child thread should have a copy of most of the
395 parent thread structure's run control related fields, not just these.
396 Initialized to avoid "may be used uninitialized" warnings from gcc. */
397 struct breakpoint
*step_resume_breakpoint
= NULL
;
398 struct breakpoint
*exception_resume_breakpoint
= NULL
;
399 CORE_ADDR step_range_start
= 0;
400 CORE_ADDR step_range_end
= 0;
401 struct frame_id step_frame_id
= { 0 };
406 struct target_waitstatus wait_status
;
408 /* Get the last target status returned by target_wait(). */
409 get_last_target_status (&wait_ptid
, &wait_status
);
411 /* If not stopped at a fork event, then there's nothing else to
413 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
414 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
417 /* Check if we switched over from WAIT_PTID, since the event was
419 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
420 && !ptid_equal (inferior_ptid
, wait_ptid
))
422 /* We did. Switch back to WAIT_PTID thread, to tell the
423 target to follow it (in either direction). We'll
424 afterwards refuse to resume, and inform the user what
426 switch_to_thread (wait_ptid
);
431 tp
= inferior_thread ();
433 /* If there were any forks/vforks that were caught and are now to be
434 followed, then do so now. */
435 switch (tp
->pending_follow
.kind
)
437 case TARGET_WAITKIND_FORKED
:
438 case TARGET_WAITKIND_VFORKED
:
440 ptid_t parent
, child
;
442 /* If the user did a next/step, etc, over a fork call,
443 preserve the stepping state in the fork child. */
444 if (follow_child
&& should_resume
)
446 step_resume_breakpoint
= clone_momentary_breakpoint
447 (tp
->control
.step_resume_breakpoint
);
448 step_range_start
= tp
->control
.step_range_start
;
449 step_range_end
= tp
->control
.step_range_end
;
450 step_frame_id
= tp
->control
.step_frame_id
;
451 exception_resume_breakpoint
452 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
454 /* For now, delete the parent's sr breakpoint, otherwise,
455 parent/child sr breakpoints are considered duplicates,
456 and the child version will not be installed. Remove
457 this when the breakpoints module becomes aware of
458 inferiors and address spaces. */
459 delete_step_resume_breakpoint (tp
);
460 tp
->control
.step_range_start
= 0;
461 tp
->control
.step_range_end
= 0;
462 tp
->control
.step_frame_id
= null_frame_id
;
463 delete_exception_resume_breakpoint (tp
);
466 parent
= inferior_ptid
;
467 child
= tp
->pending_follow
.value
.related_pid
;
469 /* Tell the target to do whatever is necessary to follow
470 either parent or child. */
471 if (target_follow_fork (follow_child
))
473 /* Target refused to follow, or there's some other reason
474 we shouldn't resume. */
479 /* This pending follow fork event is now handled, one way
480 or another. The previous selected thread may be gone
481 from the lists by now, but if it is still around, need
482 to clear the pending follow request. */
483 tp
= find_thread_ptid (parent
);
485 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
487 /* This makes sure we don't try to apply the "Switched
488 over from WAIT_PID" logic above. */
489 nullify_last_target_wait_ptid ();
491 /* If we followed the child, switch to it... */
494 switch_to_thread (child
);
496 /* ... and preserve the stepping state, in case the
497 user was stepping over the fork call. */
500 tp
= inferior_thread ();
501 tp
->control
.step_resume_breakpoint
502 = step_resume_breakpoint
;
503 tp
->control
.step_range_start
= step_range_start
;
504 tp
->control
.step_range_end
= step_range_end
;
505 tp
->control
.step_frame_id
= step_frame_id
;
506 tp
->control
.exception_resume_breakpoint
507 = exception_resume_breakpoint
;
511 /* If we get here, it was because we're trying to
512 resume from a fork catchpoint, but, the user
513 has switched threads away from the thread that
514 forked. In that case, the resume command
515 issued is most likely not applicable to the
516 child, so just warn, and refuse to resume. */
517 warning (_("Not resuming: switched threads "
518 "before following fork child.\n"));
521 /* Reset breakpoints in the child as appropriate. */
522 follow_inferior_reset_breakpoints ();
525 switch_to_thread (parent
);
529 case TARGET_WAITKIND_SPURIOUS
:
530 /* Nothing to follow. */
533 internal_error (__FILE__
, __LINE__
,
534 "Unexpected pending_follow.kind %d\n",
535 tp
->pending_follow
.kind
);
539 return should_resume
;
543 follow_inferior_reset_breakpoints (void)
545 struct thread_info
*tp
= inferior_thread ();
547 /* Was there a step_resume breakpoint? (There was if the user
548 did a "next" at the fork() call.) If so, explicitly reset its
551 step_resumes are a form of bp that are made to be per-thread.
552 Since we created the step_resume bp when the parent process
553 was being debugged, and now are switching to the child process,
554 from the breakpoint package's viewpoint, that's a switch of
555 "threads". We must update the bp's notion of which thread
556 it is for, or it'll be ignored when it triggers. */
558 if (tp
->control
.step_resume_breakpoint
)
559 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
561 if (tp
->control
.exception_resume_breakpoint
)
562 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
564 /* Reinsert all breakpoints in the child. The user may have set
565 breakpoints after catching the fork, in which case those
566 were never set in the child, but only in the parent. This makes
567 sure the inserted breakpoints match the breakpoint list. */
569 breakpoint_re_set ();
570 insert_breakpoints ();
573 /* The child has exited or execed: resume threads of the parent the
574 user wanted to be executing. */
577 proceed_after_vfork_done (struct thread_info
*thread
,
580 int pid
= * (int *) arg
;
582 if (ptid_get_pid (thread
->ptid
) == pid
583 && is_running (thread
->ptid
)
584 && !is_executing (thread
->ptid
)
585 && !thread
->stop_requested
586 && thread
->suspend
.stop_signal
== TARGET_SIGNAL_0
)
589 fprintf_unfiltered (gdb_stdlog
,
590 "infrun: resuming vfork parent thread %s\n",
591 target_pid_to_str (thread
->ptid
));
593 switch_to_thread (thread
->ptid
);
594 clear_proceed_status ();
595 proceed ((CORE_ADDR
) -1, TARGET_SIGNAL_DEFAULT
, 0);
601 /* Called whenever we notice an exec or exit event, to handle
602 detaching or resuming a vfork parent. */
605 handle_vfork_child_exec_or_exit (int exec
)
607 struct inferior
*inf
= current_inferior ();
609 if (inf
->vfork_parent
)
611 int resume_parent
= -1;
613 /* This exec or exit marks the end of the shared memory region
614 between the parent and the child. If the user wanted to
615 detach from the parent, now is the time. */
617 if (inf
->vfork_parent
->pending_detach
)
619 struct thread_info
*tp
;
620 struct cleanup
*old_chain
;
621 struct program_space
*pspace
;
622 struct address_space
*aspace
;
624 /* follow-fork child, detach-on-fork on. */
626 old_chain
= make_cleanup_restore_current_thread ();
628 /* We're letting loose of the parent. */
629 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
630 switch_to_thread (tp
->ptid
);
632 /* We're about to detach from the parent, which implicitly
633 removes breakpoints from its address space. There's a
634 catch here: we want to reuse the spaces for the child,
635 but, parent/child are still sharing the pspace at this
636 point, although the exec in reality makes the kernel give
637 the child a fresh set of new pages. The problem here is
638 that the breakpoints module being unaware of this, would
639 likely chose the child process to write to the parent
640 address space. Swapping the child temporarily away from
641 the spaces has the desired effect. Yes, this is "sort
644 pspace
= inf
->pspace
;
645 aspace
= inf
->aspace
;
649 if (debug_infrun
|| info_verbose
)
651 target_terminal_ours ();
654 fprintf_filtered (gdb_stdlog
,
655 "Detaching vfork parent process "
656 "%d after child exec.\n",
657 inf
->vfork_parent
->pid
);
659 fprintf_filtered (gdb_stdlog
,
660 "Detaching vfork parent process "
661 "%d after child exit.\n",
662 inf
->vfork_parent
->pid
);
665 target_detach (NULL
, 0);
668 inf
->pspace
= pspace
;
669 inf
->aspace
= aspace
;
671 do_cleanups (old_chain
);
675 /* We're staying attached to the parent, so, really give the
676 child a new address space. */
677 inf
->pspace
= add_program_space (maybe_new_address_space ());
678 inf
->aspace
= inf
->pspace
->aspace
;
680 set_current_program_space (inf
->pspace
);
682 resume_parent
= inf
->vfork_parent
->pid
;
684 /* Break the bonds. */
685 inf
->vfork_parent
->vfork_child
= NULL
;
689 struct cleanup
*old_chain
;
690 struct program_space
*pspace
;
692 /* If this is a vfork child exiting, then the pspace and
693 aspaces were shared with the parent. Since we're
694 reporting the process exit, we'll be mourning all that is
695 found in the address space, and switching to null_ptid,
696 preparing to start a new inferior. But, since we don't
697 want to clobber the parent's address/program spaces, we
698 go ahead and create a new one for this exiting
701 /* Switch to null_ptid, so that clone_program_space doesn't want
702 to read the selected frame of a dead process. */
703 old_chain
= save_inferior_ptid ();
704 inferior_ptid
= null_ptid
;
706 /* This inferior is dead, so avoid giving the breakpoints
707 module the option to write through to it (cloning a
708 program space resets breakpoints). */
711 pspace
= add_program_space (maybe_new_address_space ());
712 set_current_program_space (pspace
);
714 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
715 inf
->pspace
= pspace
;
716 inf
->aspace
= pspace
->aspace
;
718 /* Put back inferior_ptid. We'll continue mourning this
720 do_cleanups (old_chain
);
722 resume_parent
= inf
->vfork_parent
->pid
;
723 /* Break the bonds. */
724 inf
->vfork_parent
->vfork_child
= NULL
;
727 inf
->vfork_parent
= NULL
;
729 gdb_assert (current_program_space
== inf
->pspace
);
731 if (non_stop
&& resume_parent
!= -1)
733 /* If the user wanted the parent to be running, let it go
735 struct cleanup
*old_chain
= make_cleanup_restore_current_thread ();
738 fprintf_unfiltered (gdb_stdlog
,
739 "infrun: resuming vfork parent process %d\n",
742 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
744 do_cleanups (old_chain
);
749 /* Enum strings for "set|show displaced-stepping". */
751 static const char follow_exec_mode_new
[] = "new";
752 static const char follow_exec_mode_same
[] = "same";
753 static const char *follow_exec_mode_names
[] =
755 follow_exec_mode_new
,
756 follow_exec_mode_same
,
760 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
762 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
763 struct cmd_list_element
*c
, const char *value
)
765 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
768 /* EXECD_PATHNAME is assumed to be non-NULL. */
771 follow_exec (ptid_t pid
, char *execd_pathname
)
773 struct thread_info
*th
= inferior_thread ();
774 struct inferior
*inf
= current_inferior ();
776 /* This is an exec event that we actually wish to pay attention to.
777 Refresh our symbol table to the newly exec'd program, remove any
780 If there are breakpoints, they aren't really inserted now,
781 since the exec() transformed our inferior into a fresh set
784 We want to preserve symbolic breakpoints on the list, since
785 we have hopes that they can be reset after the new a.out's
786 symbol table is read.
788 However, any "raw" breakpoints must be removed from the list
789 (e.g., the solib bp's), since their address is probably invalid
792 And, we DON'T want to call delete_breakpoints() here, since
793 that may write the bp's "shadow contents" (the instruction
794 value that was overwritten witha TRAP instruction). Since
795 we now have a new a.out, those shadow contents aren't valid. */
797 mark_breakpoints_out ();
799 update_breakpoints_after_exec ();
801 /* If there was one, it's gone now. We cannot truly step-to-next
802 statement through an exec(). */
803 th
->control
.step_resume_breakpoint
= NULL
;
804 th
->control
.exception_resume_breakpoint
= NULL
;
805 th
->control
.step_range_start
= 0;
806 th
->control
.step_range_end
= 0;
808 /* The target reports the exec event to the main thread, even if
809 some other thread does the exec, and even if the main thread was
810 already stopped --- if debugging in non-stop mode, it's possible
811 the user had the main thread held stopped in the previous image
812 --- release it now. This is the same behavior as step-over-exec
813 with scheduler-locking on in all-stop mode. */
814 th
->stop_requested
= 0;
816 /* What is this a.out's name? */
817 printf_unfiltered (_("%s is executing new program: %s\n"),
818 target_pid_to_str (inferior_ptid
),
821 /* We've followed the inferior through an exec. Therefore, the
822 inferior has essentially been killed & reborn. */
824 gdb_flush (gdb_stdout
);
826 breakpoint_init_inferior (inf_execd
);
828 if (gdb_sysroot
&& *gdb_sysroot
)
830 char *name
= alloca (strlen (gdb_sysroot
)
831 + strlen (execd_pathname
)
834 strcpy (name
, gdb_sysroot
);
835 strcat (name
, execd_pathname
);
836 execd_pathname
= name
;
839 /* Reset the shared library package. This ensures that we get a
840 shlib event when the child reaches "_start", at which point the
841 dld will have had a chance to initialize the child. */
842 /* Also, loading a symbol file below may trigger symbol lookups, and
843 we don't want those to be satisfied by the libraries of the
844 previous incarnation of this process. */
845 no_shared_libraries (NULL
, 0);
847 if (follow_exec_mode_string
== follow_exec_mode_new
)
849 struct program_space
*pspace
;
851 /* The user wants to keep the old inferior and program spaces
852 around. Create a new fresh one, and switch to it. */
854 inf
= add_inferior (current_inferior ()->pid
);
855 pspace
= add_program_space (maybe_new_address_space ());
856 inf
->pspace
= pspace
;
857 inf
->aspace
= pspace
->aspace
;
859 exit_inferior_num_silent (current_inferior ()->num
);
861 set_current_inferior (inf
);
862 set_current_program_space (pspace
);
865 gdb_assert (current_program_space
== inf
->pspace
);
867 /* That a.out is now the one to use. */
868 exec_file_attach (execd_pathname
, 0);
870 /* SYMFILE_DEFER_BP_RESET is used as the proper displacement for PIE
871 (Position Independent Executable) main symbol file will get applied by
872 solib_create_inferior_hook below. breakpoint_re_set would fail to insert
873 the breakpoints with the zero displacement. */
875 symbol_file_add (execd_pathname
, SYMFILE_MAINLINE
| SYMFILE_DEFER_BP_RESET
,
878 set_initial_language ();
880 #ifdef SOLIB_CREATE_INFERIOR_HOOK
881 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid
));
883 solib_create_inferior_hook (0);
886 jit_inferior_created_hook ();
888 breakpoint_re_set ();
890 /* Reinsert all breakpoints. (Those which were symbolic have
891 been reset to the proper address in the new a.out, thanks
892 to symbol_file_command...). */
893 insert_breakpoints ();
895 /* The next resume of this inferior should bring it to the shlib
896 startup breakpoints. (If the user had also set bp's on
897 "main" from the old (parent) process, then they'll auto-
898 matically get reset there in the new process.). */
901 /* Non-zero if we just simulating a single-step. This is needed
902 because we cannot remove the breakpoints in the inferior process
903 until after the `wait' in `wait_for_inferior'. */
904 static int singlestep_breakpoints_inserted_p
= 0;
906 /* The thread we inserted single-step breakpoints for. */
907 static ptid_t singlestep_ptid
;
909 /* PC when we started this single-step. */
910 static CORE_ADDR singlestep_pc
;
912 /* If another thread hit the singlestep breakpoint, we save the original
913 thread here so that we can resume single-stepping it later. */
914 static ptid_t saved_singlestep_ptid
;
915 static int stepping_past_singlestep_breakpoint
;
917 /* If not equal to null_ptid, this means that after stepping over breakpoint
918 is finished, we need to switch to deferred_step_ptid, and step it.
920 The use case is when one thread has hit a breakpoint, and then the user
921 has switched to another thread and issued 'step'. We need to step over
922 breakpoint in the thread which hit the breakpoint, but then continue
923 stepping the thread user has selected. */
924 static ptid_t deferred_step_ptid
;
926 /* Displaced stepping. */
928 /* In non-stop debugging mode, we must take special care to manage
929 breakpoints properly; in particular, the traditional strategy for
930 stepping a thread past a breakpoint it has hit is unsuitable.
931 'Displaced stepping' is a tactic for stepping one thread past a
932 breakpoint it has hit while ensuring that other threads running
933 concurrently will hit the breakpoint as they should.
935 The traditional way to step a thread T off a breakpoint in a
936 multi-threaded program in all-stop mode is as follows:
938 a0) Initially, all threads are stopped, and breakpoints are not
940 a1) We single-step T, leaving breakpoints uninserted.
941 a2) We insert breakpoints, and resume all threads.
943 In non-stop debugging, however, this strategy is unsuitable: we
944 don't want to have to stop all threads in the system in order to
945 continue or step T past a breakpoint. Instead, we use displaced
948 n0) Initially, T is stopped, other threads are running, and
949 breakpoints are inserted.
950 n1) We copy the instruction "under" the breakpoint to a separate
951 location, outside the main code stream, making any adjustments
952 to the instruction, register, and memory state as directed by
954 n2) We single-step T over the instruction at its new location.
955 n3) We adjust the resulting register and memory state as directed
956 by T's architecture. This includes resetting T's PC to point
957 back into the main instruction stream.
960 This approach depends on the following gdbarch methods:
962 - gdbarch_max_insn_length and gdbarch_displaced_step_location
963 indicate where to copy the instruction, and how much space must
964 be reserved there. We use these in step n1.
966 - gdbarch_displaced_step_copy_insn copies a instruction to a new
967 address, and makes any necessary adjustments to the instruction,
968 register contents, and memory. We use this in step n1.
970 - gdbarch_displaced_step_fixup adjusts registers and memory after
971 we have successfuly single-stepped the instruction, to yield the
972 same effect the instruction would have had if we had executed it
973 at its original address. We use this in step n3.
975 - gdbarch_displaced_step_free_closure provides cleanup.
977 The gdbarch_displaced_step_copy_insn and
978 gdbarch_displaced_step_fixup functions must be written so that
979 copying an instruction with gdbarch_displaced_step_copy_insn,
980 single-stepping across the copied instruction, and then applying
981 gdbarch_displaced_insn_fixup should have the same effects on the
982 thread's memory and registers as stepping the instruction in place
983 would have. Exactly which responsibilities fall to the copy and
984 which fall to the fixup is up to the author of those functions.
986 See the comments in gdbarch.sh for details.
988 Note that displaced stepping and software single-step cannot
989 currently be used in combination, although with some care I think
990 they could be made to. Software single-step works by placing
991 breakpoints on all possible subsequent instructions; if the
992 displaced instruction is a PC-relative jump, those breakpoints
993 could fall in very strange places --- on pages that aren't
994 executable, or at addresses that are not proper instruction
995 boundaries. (We do generally let other threads run while we wait
996 to hit the software single-step breakpoint, and they might
997 encounter such a corrupted instruction.) One way to work around
998 this would be to have gdbarch_displaced_step_copy_insn fully
999 simulate the effect of PC-relative instructions (and return NULL)
1000 on architectures that use software single-stepping.
1002 In non-stop mode, we can have independent and simultaneous step
1003 requests, so more than one thread may need to simultaneously step
1004 over a breakpoint. The current implementation assumes there is
1005 only one scratch space per process. In this case, we have to
1006 serialize access to the scratch space. If thread A wants to step
1007 over a breakpoint, but we are currently waiting for some other
1008 thread to complete a displaced step, we leave thread A stopped and
1009 place it in the displaced_step_request_queue. Whenever a displaced
1010 step finishes, we pick the next thread in the queue and start a new
1011 displaced step operation on it. See displaced_step_prepare and
1012 displaced_step_fixup for details. */
1014 struct displaced_step_request
1017 struct displaced_step_request
*next
;
1020 /* Per-inferior displaced stepping state. */
1021 struct displaced_step_inferior_state
1023 /* Pointer to next in linked list. */
1024 struct displaced_step_inferior_state
*next
;
1026 /* The process this displaced step state refers to. */
1029 /* A queue of pending displaced stepping requests. One entry per
1030 thread that needs to do a displaced step. */
1031 struct displaced_step_request
*step_request_queue
;
1033 /* If this is not null_ptid, this is the thread carrying out a
1034 displaced single-step in process PID. This thread's state will
1035 require fixing up once it has completed its step. */
1038 /* The architecture the thread had when we stepped it. */
1039 struct gdbarch
*step_gdbarch
;
1041 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1042 for post-step cleanup. */
1043 struct displaced_step_closure
*step_closure
;
1045 /* The address of the original instruction, and the copy we
1047 CORE_ADDR step_original
, step_copy
;
1049 /* Saved contents of copy area. */
1050 gdb_byte
*step_saved_copy
;
1053 /* The list of states of processes involved in displaced stepping
1055 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1057 /* Get the displaced stepping state of process PID. */
1059 static struct displaced_step_inferior_state
*
1060 get_displaced_stepping_state (int pid
)
1062 struct displaced_step_inferior_state
*state
;
1064 for (state
= displaced_step_inferior_states
;
1066 state
= state
->next
)
1067 if (state
->pid
== pid
)
1073 /* Add a new displaced stepping state for process PID to the displaced
1074 stepping state list, or return a pointer to an already existing
1075 entry, if it already exists. Never returns NULL. */
1077 static struct displaced_step_inferior_state
*
1078 add_displaced_stepping_state (int pid
)
1080 struct displaced_step_inferior_state
*state
;
1082 for (state
= displaced_step_inferior_states
;
1084 state
= state
->next
)
1085 if (state
->pid
== pid
)
1088 state
= xcalloc (1, sizeof (*state
));
1090 state
->next
= displaced_step_inferior_states
;
1091 displaced_step_inferior_states
= state
;
1096 /* If inferior is in displaced stepping, and ADDR equals to starting address
1097 of copy area, return corresponding displaced_step_closure. Otherwise,
1100 struct displaced_step_closure
*
1101 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1103 struct displaced_step_inferior_state
*displaced
1104 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1106 /* If checking the mode of displaced instruction in copy area. */
1107 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1108 && (displaced
->step_copy
== addr
))
1109 return displaced
->step_closure
;
1114 /* Remove the displaced stepping state of process PID. */
1117 remove_displaced_stepping_state (int pid
)
1119 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1121 gdb_assert (pid
!= 0);
1123 it
= displaced_step_inferior_states
;
1124 prev_next_p
= &displaced_step_inferior_states
;
1129 *prev_next_p
= it
->next
;
1134 prev_next_p
= &it
->next
;
1140 infrun_inferior_exit (struct inferior
*inf
)
1142 remove_displaced_stepping_state (inf
->pid
);
1145 /* Enum strings for "set|show displaced-stepping". */
1147 static const char can_use_displaced_stepping_auto
[] = "auto";
1148 static const char can_use_displaced_stepping_on
[] = "on";
1149 static const char can_use_displaced_stepping_off
[] = "off";
1150 static const char *can_use_displaced_stepping_enum
[] =
1152 can_use_displaced_stepping_auto
,
1153 can_use_displaced_stepping_on
,
1154 can_use_displaced_stepping_off
,
1158 /* If ON, and the architecture supports it, GDB will use displaced
1159 stepping to step over breakpoints. If OFF, or if the architecture
1160 doesn't support it, GDB will instead use the traditional
1161 hold-and-step approach. If AUTO (which is the default), GDB will
1162 decide which technique to use to step over breakpoints depending on
1163 which of all-stop or non-stop mode is active --- displaced stepping
1164 in non-stop mode; hold-and-step in all-stop mode. */
1166 static const char *can_use_displaced_stepping
=
1167 can_use_displaced_stepping_auto
;
1170 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1171 struct cmd_list_element
*c
,
1174 if (can_use_displaced_stepping
== can_use_displaced_stepping_auto
)
1175 fprintf_filtered (file
,
1176 _("Debugger's willingness to use displaced stepping "
1177 "to step over breakpoints is %s (currently %s).\n"),
1178 value
, non_stop
? "on" : "off");
1180 fprintf_filtered (file
,
1181 _("Debugger's willingness to use displaced stepping "
1182 "to step over breakpoints is %s.\n"), value
);
1185 /* Return non-zero if displaced stepping can/should be used to step
1186 over breakpoints. */
1189 use_displaced_stepping (struct gdbarch
*gdbarch
)
1191 return (((can_use_displaced_stepping
== can_use_displaced_stepping_auto
1193 || can_use_displaced_stepping
== can_use_displaced_stepping_on
)
1194 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1195 && !RECORD_IS_USED
);
1198 /* Clean out any stray displaced stepping state. */
1200 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1202 /* Indicate that there is no cleanup pending. */
1203 displaced
->step_ptid
= null_ptid
;
1205 if (displaced
->step_closure
)
1207 gdbarch_displaced_step_free_closure (displaced
->step_gdbarch
,
1208 displaced
->step_closure
);
1209 displaced
->step_closure
= NULL
;
1214 displaced_step_clear_cleanup (void *arg
)
1216 struct displaced_step_inferior_state
*state
= arg
;
1218 displaced_step_clear (state
);
1221 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1223 displaced_step_dump_bytes (struct ui_file
*file
,
1224 const gdb_byte
*buf
,
1229 for (i
= 0; i
< len
; i
++)
1230 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1231 fputs_unfiltered ("\n", file
);
1234 /* Prepare to single-step, using displaced stepping.
1236 Note that we cannot use displaced stepping when we have a signal to
1237 deliver. If we have a signal to deliver and an instruction to step
1238 over, then after the step, there will be no indication from the
1239 target whether the thread entered a signal handler or ignored the
1240 signal and stepped over the instruction successfully --- both cases
1241 result in a simple SIGTRAP. In the first case we mustn't do a
1242 fixup, and in the second case we must --- but we can't tell which.
1243 Comments in the code for 'random signals' in handle_inferior_event
1244 explain how we handle this case instead.
1246 Returns 1 if preparing was successful -- this thread is going to be
1247 stepped now; or 0 if displaced stepping this thread got queued. */
1249 displaced_step_prepare (ptid_t ptid
)
1251 struct cleanup
*old_cleanups
, *ignore_cleanups
;
1252 struct regcache
*regcache
= get_thread_regcache (ptid
);
1253 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1254 CORE_ADDR original
, copy
;
1256 struct displaced_step_closure
*closure
;
1257 struct displaced_step_inferior_state
*displaced
;
1259 /* We should never reach this function if the architecture does not
1260 support displaced stepping. */
1261 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1263 /* We have to displaced step one thread at a time, as we only have
1264 access to a single scratch space per inferior. */
1266 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1268 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1270 /* Already waiting for a displaced step to finish. Defer this
1271 request and place in queue. */
1272 struct displaced_step_request
*req
, *new_req
;
1274 if (debug_displaced
)
1275 fprintf_unfiltered (gdb_stdlog
,
1276 "displaced: defering step of %s\n",
1277 target_pid_to_str (ptid
));
1279 new_req
= xmalloc (sizeof (*new_req
));
1280 new_req
->ptid
= ptid
;
1281 new_req
->next
= NULL
;
1283 if (displaced
->step_request_queue
)
1285 for (req
= displaced
->step_request_queue
;
1289 req
->next
= new_req
;
1292 displaced
->step_request_queue
= new_req
;
1298 if (debug_displaced
)
1299 fprintf_unfiltered (gdb_stdlog
,
1300 "displaced: stepping %s now\n",
1301 target_pid_to_str (ptid
));
1304 displaced_step_clear (displaced
);
1306 old_cleanups
= save_inferior_ptid ();
1307 inferior_ptid
= ptid
;
1309 original
= regcache_read_pc (regcache
);
1311 copy
= gdbarch_displaced_step_location (gdbarch
);
1312 len
= gdbarch_max_insn_length (gdbarch
);
1314 /* Save the original contents of the copy area. */
1315 displaced
->step_saved_copy
= xmalloc (len
);
1316 ignore_cleanups
= make_cleanup (free_current_contents
,
1317 &displaced
->step_saved_copy
);
1318 read_memory (copy
, displaced
->step_saved_copy
, len
);
1319 if (debug_displaced
)
1321 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1322 paddress (gdbarch
, copy
));
1323 displaced_step_dump_bytes (gdb_stdlog
,
1324 displaced
->step_saved_copy
,
1328 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1329 original
, copy
, regcache
);
1331 /* We don't support the fully-simulated case at present. */
1332 gdb_assert (closure
);
1334 /* Save the information we need to fix things up if the step
1336 displaced
->step_ptid
= ptid
;
1337 displaced
->step_gdbarch
= gdbarch
;
1338 displaced
->step_closure
= closure
;
1339 displaced
->step_original
= original
;
1340 displaced
->step_copy
= copy
;
1342 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1344 /* Resume execution at the copy. */
1345 regcache_write_pc (regcache
, copy
);
1347 discard_cleanups (ignore_cleanups
);
1349 do_cleanups (old_cleanups
);
1351 if (debug_displaced
)
1352 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1353 paddress (gdbarch
, copy
));
1359 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1360 const gdb_byte
*myaddr
, int len
)
1362 struct cleanup
*ptid_cleanup
= save_inferior_ptid ();
1364 inferior_ptid
= ptid
;
1365 write_memory (memaddr
, myaddr
, len
);
1366 do_cleanups (ptid_cleanup
);
1370 displaced_step_fixup (ptid_t event_ptid
, enum target_signal signal
)
1372 struct cleanup
*old_cleanups
;
1373 struct displaced_step_inferior_state
*displaced
1374 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1376 /* Was any thread of this process doing a displaced step? */
1377 if (displaced
== NULL
)
1380 /* Was this event for the pid we displaced? */
1381 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1382 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1385 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1387 /* Restore the contents of the copy area. */
1389 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1391 write_memory_ptid (displaced
->step_ptid
, displaced
->step_copy
,
1392 displaced
->step_saved_copy
, len
);
1393 if (debug_displaced
)
1394 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s\n",
1395 paddress (displaced
->step_gdbarch
,
1396 displaced
->step_copy
));
1399 /* Did the instruction complete successfully? */
1400 if (signal
== TARGET_SIGNAL_TRAP
)
1402 /* Fix up the resulting state. */
1403 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1404 displaced
->step_closure
,
1405 displaced
->step_original
,
1406 displaced
->step_copy
,
1407 get_thread_regcache (displaced
->step_ptid
));
1411 /* Since the instruction didn't complete, all we can do is
1413 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
1414 CORE_ADDR pc
= regcache_read_pc (regcache
);
1416 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1417 regcache_write_pc (regcache
, pc
);
1420 do_cleanups (old_cleanups
);
1422 displaced
->step_ptid
= null_ptid
;
1424 /* Are there any pending displaced stepping requests? If so, run
1425 one now. Leave the state object around, since we're likely to
1426 need it again soon. */
1427 while (displaced
->step_request_queue
)
1429 struct displaced_step_request
*head
;
1431 struct regcache
*regcache
;
1432 struct gdbarch
*gdbarch
;
1433 CORE_ADDR actual_pc
;
1434 struct address_space
*aspace
;
1436 head
= displaced
->step_request_queue
;
1438 displaced
->step_request_queue
= head
->next
;
1441 context_switch (ptid
);
1443 regcache
= get_thread_regcache (ptid
);
1444 actual_pc
= regcache_read_pc (regcache
);
1445 aspace
= get_regcache_aspace (regcache
);
1447 if (breakpoint_here_p (aspace
, actual_pc
))
1449 if (debug_displaced
)
1450 fprintf_unfiltered (gdb_stdlog
,
1451 "displaced: stepping queued %s now\n",
1452 target_pid_to_str (ptid
));
1454 displaced_step_prepare (ptid
);
1456 gdbarch
= get_regcache_arch (regcache
);
1458 if (debug_displaced
)
1460 CORE_ADDR actual_pc
= regcache_read_pc (regcache
);
1463 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1464 paddress (gdbarch
, actual_pc
));
1465 read_memory (actual_pc
, buf
, sizeof (buf
));
1466 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1469 if (gdbarch_displaced_step_hw_singlestep (gdbarch
,
1470 displaced
->step_closure
))
1471 target_resume (ptid
, 1, TARGET_SIGNAL_0
);
1473 target_resume (ptid
, 0, TARGET_SIGNAL_0
);
1475 /* Done, we're stepping a thread. */
1481 struct thread_info
*tp
= inferior_thread ();
1483 /* The breakpoint we were sitting under has since been
1485 tp
->control
.trap_expected
= 0;
1487 /* Go back to what we were trying to do. */
1488 step
= currently_stepping (tp
);
1490 if (debug_displaced
)
1491 fprintf_unfiltered (gdb_stdlog
,
1492 "breakpoint is gone %s: step(%d)\n",
1493 target_pid_to_str (tp
->ptid
), step
);
1495 target_resume (ptid
, step
, TARGET_SIGNAL_0
);
1496 tp
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
1498 /* This request was discarded. See if there's any other
1499 thread waiting for its turn. */
1504 /* Update global variables holding ptids to hold NEW_PTID if they were
1505 holding OLD_PTID. */
1507 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
1509 struct displaced_step_request
*it
;
1510 struct displaced_step_inferior_state
*displaced
;
1512 if (ptid_equal (inferior_ptid
, old_ptid
))
1513 inferior_ptid
= new_ptid
;
1515 if (ptid_equal (singlestep_ptid
, old_ptid
))
1516 singlestep_ptid
= new_ptid
;
1518 if (ptid_equal (deferred_step_ptid
, old_ptid
))
1519 deferred_step_ptid
= new_ptid
;
1521 for (displaced
= displaced_step_inferior_states
;
1523 displaced
= displaced
->next
)
1525 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
1526 displaced
->step_ptid
= new_ptid
;
1528 for (it
= displaced
->step_request_queue
; it
; it
= it
->next
)
1529 if (ptid_equal (it
->ptid
, old_ptid
))
1530 it
->ptid
= new_ptid
;
1537 /* Things to clean up if we QUIT out of resume (). */
1539 resume_cleanups (void *ignore
)
1544 static const char schedlock_off
[] = "off";
1545 static const char schedlock_on
[] = "on";
1546 static const char schedlock_step
[] = "step";
1547 static const char *scheduler_enums
[] = {
1553 static const char *scheduler_mode
= schedlock_off
;
1555 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1556 struct cmd_list_element
*c
, const char *value
)
1558 fprintf_filtered (file
,
1559 _("Mode for locking scheduler "
1560 "during execution is \"%s\".\n"),
1565 set_schedlock_func (char *args
, int from_tty
, struct cmd_list_element
*c
)
1567 if (!target_can_lock_scheduler
)
1569 scheduler_mode
= schedlock_off
;
1570 error (_("Target '%s' cannot support this command."), target_shortname
);
1574 /* True if execution commands resume all threads of all processes by
1575 default; otherwise, resume only threads of the current inferior
1577 int sched_multi
= 0;
1579 /* Try to setup for software single stepping over the specified location.
1580 Return 1 if target_resume() should use hardware single step.
1582 GDBARCH the current gdbarch.
1583 PC the location to step over. */
1586 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1590 if (execution_direction
== EXEC_FORWARD
1591 && gdbarch_software_single_step_p (gdbarch
)
1592 && gdbarch_software_single_step (gdbarch
, get_current_frame ()))
1595 /* Do not pull these breakpoints until after a `wait' in
1596 `wait_for_inferior'. */
1597 singlestep_breakpoints_inserted_p
= 1;
1598 singlestep_ptid
= inferior_ptid
;
1604 /* Resume the inferior, but allow a QUIT. This is useful if the user
1605 wants to interrupt some lengthy single-stepping operation
1606 (for child processes, the SIGINT goes to the inferior, and so
1607 we get a SIGINT random_signal, but for remote debugging and perhaps
1608 other targets, that's not true).
1610 STEP nonzero if we should step (zero to continue instead).
1611 SIG is the signal to give the inferior (zero for none). */
1613 resume (int step
, enum target_signal sig
)
1615 int should_resume
= 1;
1616 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
1617 struct regcache
*regcache
= get_current_regcache ();
1618 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
1619 struct thread_info
*tp
= inferior_thread ();
1620 CORE_ADDR pc
= regcache_read_pc (regcache
);
1621 struct address_space
*aspace
= get_regcache_aspace (regcache
);
1625 if (current_inferior ()->waiting_for_vfork_done
)
1627 /* Don't try to single-step a vfork parent that is waiting for
1628 the child to get out of the shared memory region (by exec'ing
1629 or exiting). This is particularly important on software
1630 single-step archs, as the child process would trip on the
1631 software single step breakpoint inserted for the parent
1632 process. Since the parent will not actually execute any
1633 instruction until the child is out of the shared region (such
1634 are vfork's semantics), it is safe to simply continue it.
1635 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
1636 the parent, and tell it to `keep_going', which automatically
1637 re-sets it stepping. */
1639 fprintf_unfiltered (gdb_stdlog
,
1640 "infrun: resume : clear step\n");
1645 fprintf_unfiltered (gdb_stdlog
,
1646 "infrun: resume (step=%d, signal=%d), "
1647 "trap_expected=%d\n",
1648 step
, sig
, tp
->control
.trap_expected
);
1650 /* Normally, by the time we reach `resume', the breakpoints are either
1651 removed or inserted, as appropriate. The exception is if we're sitting
1652 at a permanent breakpoint; we need to step over it, but permanent
1653 breakpoints can't be removed. So we have to test for it here. */
1654 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
1656 if (gdbarch_skip_permanent_breakpoint_p (gdbarch
))
1657 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
1660 The program is stopped at a permanent breakpoint, but GDB does not know\n\
1661 how to step past a permanent breakpoint on this architecture. Try using\n\
1662 a command like `return' or `jump' to continue execution."));
1665 /* If enabled, step over breakpoints by executing a copy of the
1666 instruction at a different address.
1668 We can't use displaced stepping when we have a signal to deliver;
1669 the comments for displaced_step_prepare explain why. The
1670 comments in the handle_inferior event for dealing with 'random
1671 signals' explain what we do instead.
1673 We can't use displaced stepping when we are waiting for vfork_done
1674 event, displaced stepping breaks the vfork child similarly as single
1675 step software breakpoint. */
1676 if (use_displaced_stepping (gdbarch
)
1677 && (tp
->control
.trap_expected
1678 || (step
&& gdbarch_software_single_step_p (gdbarch
)))
1679 && sig
== TARGET_SIGNAL_0
1680 && !current_inferior ()->waiting_for_vfork_done
)
1682 struct displaced_step_inferior_state
*displaced
;
1684 if (!displaced_step_prepare (inferior_ptid
))
1686 /* Got placed in displaced stepping queue. Will be resumed
1687 later when all the currently queued displaced stepping
1688 requests finish. The thread is not executing at this point,
1689 and the call to set_executing will be made later. But we
1690 need to call set_running here, since from frontend point of view,
1691 the thread is running. */
1692 set_running (inferior_ptid
, 1);
1693 discard_cleanups (old_cleanups
);
1697 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1698 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
1699 displaced
->step_closure
);
1702 /* Do we need to do it the hard way, w/temp breakpoints? */
1704 step
= maybe_software_singlestep (gdbarch
, pc
);
1706 /* Currently, our software single-step implementation leads to different
1707 results than hardware single-stepping in one situation: when stepping
1708 into delivering a signal which has an associated signal handler,
1709 hardware single-step will stop at the first instruction of the handler,
1710 while software single-step will simply skip execution of the handler.
1712 For now, this difference in behavior is accepted since there is no
1713 easy way to actually implement single-stepping into a signal handler
1714 without kernel support.
1716 However, there is one scenario where this difference leads to follow-on
1717 problems: if we're stepping off a breakpoint by removing all breakpoints
1718 and then single-stepping. In this case, the software single-step
1719 behavior means that even if there is a *breakpoint* in the signal
1720 handler, GDB still would not stop.
1722 Fortunately, we can at least fix this particular issue. We detect
1723 here the case where we are about to deliver a signal while software
1724 single-stepping with breakpoints removed. In this situation, we
1725 revert the decisions to remove all breakpoints and insert single-
1726 step breakpoints, and instead we install a step-resume breakpoint
1727 at the current address, deliver the signal without stepping, and
1728 once we arrive back at the step-resume breakpoint, actually step
1729 over the breakpoint we originally wanted to step over. */
1730 if (singlestep_breakpoints_inserted_p
1731 && tp
->control
.trap_expected
&& sig
!= TARGET_SIGNAL_0
)
1733 /* If we have nested signals or a pending signal is delivered
1734 immediately after a handler returns, might might already have
1735 a step-resume breakpoint set on the earlier handler. We cannot
1736 set another step-resume breakpoint; just continue on until the
1737 original breakpoint is hit. */
1738 if (tp
->control
.step_resume_breakpoint
== NULL
)
1740 insert_step_resume_breakpoint_at_frame (get_current_frame ());
1741 tp
->step_after_step_resume_breakpoint
= 1;
1744 remove_single_step_breakpoints ();
1745 singlestep_breakpoints_inserted_p
= 0;
1747 insert_breakpoints ();
1748 tp
->control
.trap_expected
= 0;
1755 /* If STEP is set, it's a request to use hardware stepping
1756 facilities. But in that case, we should never
1757 use singlestep breakpoint. */
1758 gdb_assert (!(singlestep_breakpoints_inserted_p
&& step
));
1760 /* Decide the set of threads to ask the target to resume. Start
1761 by assuming everything will be resumed, than narrow the set
1762 by applying increasingly restricting conditions. */
1764 /* By default, resume all threads of all processes. */
1765 resume_ptid
= RESUME_ALL
;
1767 /* Maybe resume only all threads of the current process. */
1768 if (!sched_multi
&& target_supports_multi_process ())
1770 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
1773 /* Maybe resume a single thread after all. */
1774 if (singlestep_breakpoints_inserted_p
1775 && stepping_past_singlestep_breakpoint
)
1777 /* The situation here is as follows. In thread T1 we wanted to
1778 single-step. Lacking hardware single-stepping we've
1779 set breakpoint at the PC of the next instruction -- call it
1780 P. After resuming, we've hit that breakpoint in thread T2.
1781 Now we've removed original breakpoint, inserted breakpoint
1782 at P+1, and try to step to advance T2 past breakpoint.
1783 We need to step only T2, as if T1 is allowed to freely run,
1784 it can run past P, and if other threads are allowed to run,
1785 they can hit breakpoint at P+1, and nested hits of single-step
1786 breakpoints is not something we'd want -- that's complicated
1787 to support, and has no value. */
1788 resume_ptid
= inferior_ptid
;
1790 else if ((step
|| singlestep_breakpoints_inserted_p
)
1791 && tp
->control
.trap_expected
)
1793 /* We're allowing a thread to run past a breakpoint it has
1794 hit, by single-stepping the thread with the breakpoint
1795 removed. In which case, we need to single-step only this
1796 thread, and keep others stopped, as they can miss this
1797 breakpoint if allowed to run.
1799 The current code actually removes all breakpoints when
1800 doing this, not just the one being stepped over, so if we
1801 let other threads run, we can actually miss any
1802 breakpoint, not just the one at PC. */
1803 resume_ptid
= inferior_ptid
;
1807 /* With non-stop mode on, threads are always handled
1809 resume_ptid
= inferior_ptid
;
1811 else if ((scheduler_mode
== schedlock_on
)
1812 || (scheduler_mode
== schedlock_step
1813 && (step
|| singlestep_breakpoints_inserted_p
)))
1815 /* User-settable 'scheduler' mode requires solo thread resume. */
1816 resume_ptid
= inferior_ptid
;
1819 if (gdbarch_cannot_step_breakpoint (gdbarch
))
1821 /* Most targets can step a breakpoint instruction, thus
1822 executing it normally. But if this one cannot, just
1823 continue and we will hit it anyway. */
1824 if (step
&& breakpoint_inserted_here_p (aspace
, pc
))
1829 && use_displaced_stepping (gdbarch
)
1830 && tp
->control
.trap_expected
)
1832 struct regcache
*resume_regcache
= get_thread_regcache (resume_ptid
);
1833 struct gdbarch
*resume_gdbarch
= get_regcache_arch (resume_regcache
);
1834 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
1837 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
1838 paddress (resume_gdbarch
, actual_pc
));
1839 read_memory (actual_pc
, buf
, sizeof (buf
));
1840 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
1843 /* Install inferior's terminal modes. */
1844 target_terminal_inferior ();
1846 /* Avoid confusing the next resume, if the next stop/resume
1847 happens to apply to another thread. */
1848 tp
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
1850 /* Advise target which signals may be handled silently. If we have
1851 removed breakpoints because we are stepping over one (which can
1852 happen only if we are not using displaced stepping), we need to
1853 receive all signals to avoid accidentally skipping a breakpoint
1854 during execution of a signal handler. */
1855 if ((step
|| singlestep_breakpoints_inserted_p
)
1856 && tp
->control
.trap_expected
1857 && !use_displaced_stepping (gdbarch
))
1858 target_pass_signals (0, NULL
);
1860 target_pass_signals ((int) TARGET_SIGNAL_LAST
, signal_pass
);
1862 target_resume (resume_ptid
, step
, sig
);
1865 discard_cleanups (old_cleanups
);
1870 /* Clear out all variables saying what to do when inferior is continued.
1871 First do this, then set the ones you want, then call `proceed'. */
1874 clear_proceed_status_thread (struct thread_info
*tp
)
1877 fprintf_unfiltered (gdb_stdlog
,
1878 "infrun: clear_proceed_status_thread (%s)\n",
1879 target_pid_to_str (tp
->ptid
));
1881 tp
->control
.trap_expected
= 0;
1882 tp
->control
.step_range_start
= 0;
1883 tp
->control
.step_range_end
= 0;
1884 tp
->control
.step_frame_id
= null_frame_id
;
1885 tp
->control
.step_stack_frame_id
= null_frame_id
;
1886 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
1887 tp
->stop_requested
= 0;
1889 tp
->control
.stop_step
= 0;
1891 tp
->control
.proceed_to_finish
= 0;
1893 /* Discard any remaining commands or status from previous stop. */
1894 bpstat_clear (&tp
->control
.stop_bpstat
);
1898 clear_proceed_status_callback (struct thread_info
*tp
, void *data
)
1900 if (is_exited (tp
->ptid
))
1903 clear_proceed_status_thread (tp
);
1908 clear_proceed_status (void)
1912 /* In all-stop mode, delete the per-thread status of all
1913 threads, even if inferior_ptid is null_ptid, there may be
1914 threads on the list. E.g., we may be launching a new
1915 process, while selecting the executable. */
1916 iterate_over_threads (clear_proceed_status_callback
, NULL
);
1919 if (!ptid_equal (inferior_ptid
, null_ptid
))
1921 struct inferior
*inferior
;
1925 /* If in non-stop mode, only delete the per-thread status of
1926 the current thread. */
1927 clear_proceed_status_thread (inferior_thread ());
1930 inferior
= current_inferior ();
1931 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
1934 stop_after_trap
= 0;
1936 observer_notify_about_to_proceed ();
1940 regcache_xfree (stop_registers
);
1941 stop_registers
= NULL
;
1945 /* Check the current thread against the thread that reported the most recent
1946 event. If a step-over is required return TRUE and set the current thread
1947 to the old thread. Otherwise return FALSE.
1949 This should be suitable for any targets that support threads. */
1952 prepare_to_proceed (int step
)
1955 struct target_waitstatus wait_status
;
1956 int schedlock_enabled
;
1958 /* With non-stop mode on, threads are always handled individually. */
1959 gdb_assert (! non_stop
);
1961 /* Get the last target status returned by target_wait(). */
1962 get_last_target_status (&wait_ptid
, &wait_status
);
1964 /* Make sure we were stopped at a breakpoint. */
1965 if (wait_status
.kind
!= TARGET_WAITKIND_STOPPED
1966 || (wait_status
.value
.sig
!= TARGET_SIGNAL_TRAP
1967 && wait_status
.value
.sig
!= TARGET_SIGNAL_ILL
1968 && wait_status
.value
.sig
!= TARGET_SIGNAL_SEGV
1969 && wait_status
.value
.sig
!= TARGET_SIGNAL_EMT
))
1974 schedlock_enabled
= (scheduler_mode
== schedlock_on
1975 || (scheduler_mode
== schedlock_step
1978 /* Don't switch over to WAIT_PTID if scheduler locking is on. */
1979 if (schedlock_enabled
)
1982 /* Don't switch over if we're about to resume some other process
1983 other than WAIT_PTID's, and schedule-multiple is off. */
1985 && ptid_get_pid (wait_ptid
) != ptid_get_pid (inferior_ptid
))
1988 /* Switched over from WAIT_PID. */
1989 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
1990 && !ptid_equal (inferior_ptid
, wait_ptid
))
1992 struct regcache
*regcache
= get_thread_regcache (wait_ptid
);
1994 if (breakpoint_here_p (get_regcache_aspace (regcache
),
1995 regcache_read_pc (regcache
)))
1997 /* If stepping, remember current thread to switch back to. */
1999 deferred_step_ptid
= inferior_ptid
;
2001 /* Switch back to WAIT_PID thread. */
2002 switch_to_thread (wait_ptid
);
2004 /* We return 1 to indicate that there is a breakpoint here,
2005 so we need to step over it before continuing to avoid
2006 hitting it straight away. */
2014 /* Basic routine for continuing the program in various fashions.
2016 ADDR is the address to resume at, or -1 for resume where stopped.
2017 SIGGNAL is the signal to give it, or 0 for none,
2018 or -1 for act according to how it stopped.
2019 STEP is nonzero if should trap after one instruction.
2020 -1 means return after that and print nothing.
2021 You should probably set various step_... variables
2022 before calling here, if you are stepping.
2024 You should call clear_proceed_status before calling proceed. */
2027 proceed (CORE_ADDR addr
, enum target_signal siggnal
, int step
)
2029 struct regcache
*regcache
;
2030 struct gdbarch
*gdbarch
;
2031 struct thread_info
*tp
;
2033 struct address_space
*aspace
;
2036 /* If we're stopped at a fork/vfork, follow the branch set by the
2037 "set follow-fork-mode" command; otherwise, we'll just proceed
2038 resuming the current thread. */
2039 if (!follow_fork ())
2041 /* The target for some reason decided not to resume. */
2046 regcache
= get_current_regcache ();
2047 gdbarch
= get_regcache_arch (regcache
);
2048 aspace
= get_regcache_aspace (regcache
);
2049 pc
= regcache_read_pc (regcache
);
2052 step_start_function
= find_pc_function (pc
);
2054 stop_after_trap
= 1;
2056 if (addr
== (CORE_ADDR
) -1)
2058 if (pc
== stop_pc
&& breakpoint_here_p (aspace
, pc
)
2059 && execution_direction
!= EXEC_REVERSE
)
2060 /* There is a breakpoint at the address we will resume at,
2061 step one instruction before inserting breakpoints so that
2062 we do not stop right away (and report a second hit at this
2065 Note, we don't do this in reverse, because we won't
2066 actually be executing the breakpoint insn anyway.
2067 We'll be (un-)executing the previous instruction. */
2070 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2071 && gdbarch_single_step_through_delay (gdbarch
,
2072 get_current_frame ()))
2073 /* We stepped onto an instruction that needs to be stepped
2074 again before re-inserting the breakpoint, do so. */
2079 regcache_write_pc (regcache
, addr
);
2083 fprintf_unfiltered (gdb_stdlog
,
2084 "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
2085 paddress (gdbarch
, addr
), siggnal
, step
);
2088 /* In non-stop, each thread is handled individually. The context
2089 must already be set to the right thread here. */
2093 /* In a multi-threaded task we may select another thread and
2094 then continue or step.
2096 But if the old thread was stopped at a breakpoint, it will
2097 immediately cause another breakpoint stop without any
2098 execution (i.e. it will report a breakpoint hit incorrectly).
2099 So we must step over it first.
2101 prepare_to_proceed checks the current thread against the
2102 thread that reported the most recent event. If a step-over
2103 is required it returns TRUE and sets the current thread to
2105 if (prepare_to_proceed (step
))
2109 /* prepare_to_proceed may change the current thread. */
2110 tp
= inferior_thread ();
2114 tp
->control
.trap_expected
= 1;
2115 /* If displaced stepping is enabled, we can step over the
2116 breakpoint without hitting it, so leave all breakpoints
2117 inserted. Otherwise we need to disable all breakpoints, step
2118 one instruction, and then re-add them when that step is
2120 if (!use_displaced_stepping (gdbarch
))
2121 remove_breakpoints ();
2124 /* We can insert breakpoints if we're not trying to step over one,
2125 or if we are stepping over one but we're using displaced stepping
2127 if (! tp
->control
.trap_expected
|| use_displaced_stepping (gdbarch
))
2128 insert_breakpoints ();
2132 /* Pass the last stop signal to the thread we're resuming,
2133 irrespective of whether the current thread is the thread that
2134 got the last event or not. This was historically GDB's
2135 behaviour before keeping a stop_signal per thread. */
2137 struct thread_info
*last_thread
;
2139 struct target_waitstatus last_status
;
2141 get_last_target_status (&last_ptid
, &last_status
);
2142 if (!ptid_equal (inferior_ptid
, last_ptid
)
2143 && !ptid_equal (last_ptid
, null_ptid
)
2144 && !ptid_equal (last_ptid
, minus_one_ptid
))
2146 last_thread
= find_thread_ptid (last_ptid
);
2149 tp
->suspend
.stop_signal
= last_thread
->suspend
.stop_signal
;
2150 last_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
2155 if (siggnal
!= TARGET_SIGNAL_DEFAULT
)
2156 tp
->suspend
.stop_signal
= siggnal
;
2157 /* If this signal should not be seen by program,
2158 give it zero. Used for debugging signals. */
2159 else if (!signal_program
[tp
->suspend
.stop_signal
])
2160 tp
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
2162 annotate_starting ();
2164 /* Make sure that output from GDB appears before output from the
2166 gdb_flush (gdb_stdout
);
2168 /* Refresh prev_pc value just prior to resuming. This used to be
2169 done in stop_stepping, however, setting prev_pc there did not handle
2170 scenarios such as inferior function calls or returning from
2171 a function via the return command. In those cases, the prev_pc
2172 value was not set properly for subsequent commands. The prev_pc value
2173 is used to initialize the starting line number in the ecs. With an
2174 invalid value, the gdb next command ends up stopping at the position
2175 represented by the next line table entry past our start position.
2176 On platforms that generate one line table entry per line, this
2177 is not a problem. However, on the ia64, the compiler generates
2178 extraneous line table entries that do not increase the line number.
2179 When we issue the gdb next command on the ia64 after an inferior call
2180 or a return command, we often end up a few instructions forward, still
2181 within the original line we started.
2183 An attempt was made to refresh the prev_pc at the same time the
2184 execution_control_state is initialized (for instance, just before
2185 waiting for an inferior event). But this approach did not work
2186 because of platforms that use ptrace, where the pc register cannot
2187 be read unless the inferior is stopped. At that point, we are not
2188 guaranteed the inferior is stopped and so the regcache_read_pc() call
2189 can fail. Setting the prev_pc value here ensures the value is updated
2190 correctly when the inferior is stopped. */
2191 tp
->prev_pc
= regcache_read_pc (get_current_regcache ());
2193 /* Fill in with reasonable starting values. */
2194 init_thread_stepping_state (tp
);
2196 /* Reset to normal state. */
2197 init_infwait_state ();
2199 /* Resume inferior. */
2200 resume (oneproc
|| step
|| bpstat_should_step (), tp
->suspend
.stop_signal
);
2202 /* Wait for it to stop (if not standalone)
2203 and in any case decode why it stopped, and act accordingly. */
2204 /* Do this only if we are not using the event loop, or if the target
2205 does not support asynchronous execution. */
2206 if (!target_can_async_p ())
2208 wait_for_inferior ();
2214 /* Start remote-debugging of a machine over a serial link. */
2217 start_remote (int from_tty
)
2219 struct inferior
*inferior
;
2221 init_wait_for_inferior ();
2222 inferior
= current_inferior ();
2223 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
2225 /* Always go on waiting for the target, regardless of the mode. */
2226 /* FIXME: cagney/1999-09-23: At present it isn't possible to
2227 indicate to wait_for_inferior that a target should timeout if
2228 nothing is returned (instead of just blocking). Because of this,
2229 targets expecting an immediate response need to, internally, set
2230 things up so that the target_wait() is forced to eventually
2232 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
2233 differentiate to its caller what the state of the target is after
2234 the initial open has been performed. Here we're assuming that
2235 the target has stopped. It should be possible to eventually have
2236 target_open() return to the caller an indication that the target
2237 is currently running and GDB state should be set to the same as
2238 for an async run. */
2239 wait_for_inferior ();
2241 /* Now that the inferior has stopped, do any bookkeeping like
2242 loading shared libraries. We want to do this before normal_stop,
2243 so that the displayed frame is up to date. */
2244 post_create_inferior (¤t_target
, from_tty
);
2249 /* Initialize static vars when a new inferior begins. */
2252 init_wait_for_inferior (void)
2254 /* These are meaningless until the first time through wait_for_inferior. */
2256 breakpoint_init_inferior (inf_starting
);
2258 clear_proceed_status ();
2260 stepping_past_singlestep_breakpoint
= 0;
2261 deferred_step_ptid
= null_ptid
;
2263 target_last_wait_ptid
= minus_one_ptid
;
2265 previous_inferior_ptid
= null_ptid
;
2266 init_infwait_state ();
2268 /* Discard any skipped inlined frames. */
2269 clear_inline_frame_state (minus_one_ptid
);
2273 /* This enum encodes possible reasons for doing a target_wait, so that
2274 wfi can call target_wait in one place. (Ultimately the call will be
2275 moved out of the infinite loop entirely.) */
2279 infwait_normal_state
,
2280 infwait_thread_hop_state
,
2281 infwait_step_watch_state
,
2282 infwait_nonstep_watch_state
2285 /* The PTID we'll do a target_wait on.*/
2288 /* Current inferior wait state. */
2289 enum infwait_states infwait_state
;
2291 /* Data to be passed around while handling an event. This data is
2292 discarded between events. */
2293 struct execution_control_state
2296 /* The thread that got the event, if this was a thread event; NULL
2298 struct thread_info
*event_thread
;
2300 struct target_waitstatus ws
;
2302 CORE_ADDR stop_func_start
;
2303 CORE_ADDR stop_func_end
;
2304 char *stop_func_name
;
2305 int new_thread_event
;
2309 static void handle_inferior_event (struct execution_control_state
*ecs
);
2311 static void handle_step_into_function (struct gdbarch
*gdbarch
,
2312 struct execution_control_state
*ecs
);
2313 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
2314 struct execution_control_state
*ecs
);
2315 static void check_exception_resume (struct execution_control_state
*,
2316 struct frame_info
*, struct symbol
*);
2318 static void stop_stepping (struct execution_control_state
*ecs
);
2319 static void prepare_to_wait (struct execution_control_state
*ecs
);
2320 static void keep_going (struct execution_control_state
*ecs
);
2322 /* Callback for iterate over threads. If the thread is stopped, but
2323 the user/frontend doesn't know about that yet, go through
2324 normal_stop, as if the thread had just stopped now. ARG points at
2325 a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
2326 ptid_is_pid(PTID) is true, applies to all threads of the process
2327 pointed at by PTID. Otherwise, apply only to the thread pointed by
2331 infrun_thread_stop_requested_callback (struct thread_info
*info
, void *arg
)
2333 ptid_t ptid
= * (ptid_t
*) arg
;
2335 if ((ptid_equal (info
->ptid
, ptid
)
2336 || ptid_equal (minus_one_ptid
, ptid
)
2337 || (ptid_is_pid (ptid
)
2338 && ptid_get_pid (ptid
) == ptid_get_pid (info
->ptid
)))
2339 && is_running (info
->ptid
)
2340 && !is_executing (info
->ptid
))
2342 struct cleanup
*old_chain
;
2343 struct execution_control_state ecss
;
2344 struct execution_control_state
*ecs
= &ecss
;
2346 memset (ecs
, 0, sizeof (*ecs
));
2348 old_chain
= make_cleanup_restore_current_thread ();
2350 switch_to_thread (info
->ptid
);
2352 /* Go through handle_inferior_event/normal_stop, so we always
2353 have consistent output as if the stop event had been
2355 ecs
->ptid
= info
->ptid
;
2356 ecs
->event_thread
= find_thread_ptid (info
->ptid
);
2357 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
2358 ecs
->ws
.value
.sig
= TARGET_SIGNAL_0
;
2360 handle_inferior_event (ecs
);
2362 if (!ecs
->wait_some_more
)
2364 struct thread_info
*tp
;
2368 /* Finish off the continuations. The continations
2369 themselves are responsible for realising the thread
2370 didn't finish what it was supposed to do. */
2371 tp
= inferior_thread ();
2372 do_all_intermediate_continuations_thread (tp
);
2373 do_all_continuations_thread (tp
);
2376 do_cleanups (old_chain
);
2382 /* This function is attached as a "thread_stop_requested" observer.
2383 Cleanup local state that assumed the PTID was to be resumed, and
2384 report the stop to the frontend. */
2387 infrun_thread_stop_requested (ptid_t ptid
)
2389 struct displaced_step_inferior_state
*displaced
;
2391 /* PTID was requested to stop. Remove it from the displaced
2392 stepping queue, so we don't try to resume it automatically. */
2394 for (displaced
= displaced_step_inferior_states
;
2396 displaced
= displaced
->next
)
2398 struct displaced_step_request
*it
, **prev_next_p
;
2400 it
= displaced
->step_request_queue
;
2401 prev_next_p
= &displaced
->step_request_queue
;
2404 if (ptid_match (it
->ptid
, ptid
))
2406 *prev_next_p
= it
->next
;
2412 prev_next_p
= &it
->next
;
2419 iterate_over_threads (infrun_thread_stop_requested_callback
, &ptid
);
2423 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
2425 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
2426 nullify_last_target_wait_ptid ();
2429 /* Callback for iterate_over_threads. */
2432 delete_step_resume_breakpoint_callback (struct thread_info
*info
, void *data
)
2434 if (is_exited (info
->ptid
))
2437 delete_step_resume_breakpoint (info
);
2438 delete_exception_resume_breakpoint (info
);
2442 /* In all-stop, delete the step resume breakpoint of any thread that
2443 had one. In non-stop, delete the step resume breakpoint of the
2444 thread that just stopped. */
2447 delete_step_thread_step_resume_breakpoint (void)
2449 if (!target_has_execution
2450 || ptid_equal (inferior_ptid
, null_ptid
))
2451 /* If the inferior has exited, we have already deleted the step
2452 resume breakpoints out of GDB's lists. */
2457 /* If in non-stop mode, only delete the step-resume or
2458 longjmp-resume breakpoint of the thread that just stopped
2460 struct thread_info
*tp
= inferior_thread ();
2462 delete_step_resume_breakpoint (tp
);
2463 delete_exception_resume_breakpoint (tp
);
2466 /* In all-stop mode, delete all step-resume and longjmp-resume
2467 breakpoints of any thread that had them. */
2468 iterate_over_threads (delete_step_resume_breakpoint_callback
, NULL
);
2471 /* A cleanup wrapper. */
2474 delete_step_thread_step_resume_breakpoint_cleanup (void *arg
)
2476 delete_step_thread_step_resume_breakpoint ();
2479 /* Pretty print the results of target_wait, for debugging purposes. */
2482 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
2483 const struct target_waitstatus
*ws
)
2485 char *status_string
= target_waitstatus_to_string (ws
);
2486 struct ui_file
*tmp_stream
= mem_fileopen ();
2489 /* The text is split over several lines because it was getting too long.
2490 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
2491 output as a unit; we want only one timestamp printed if debug_timestamp
2494 fprintf_unfiltered (tmp_stream
,
2495 "infrun: target_wait (%d", PIDGET (waiton_ptid
));
2496 if (PIDGET (waiton_ptid
) != -1)
2497 fprintf_unfiltered (tmp_stream
,
2498 " [%s]", target_pid_to_str (waiton_ptid
));
2499 fprintf_unfiltered (tmp_stream
, ", status) =\n");
2500 fprintf_unfiltered (tmp_stream
,
2501 "infrun: %d [%s],\n",
2502 PIDGET (result_ptid
), target_pid_to_str (result_ptid
));
2503 fprintf_unfiltered (tmp_stream
,
2507 text
= ui_file_xstrdup (tmp_stream
, NULL
);
2509 /* This uses %s in part to handle %'s in the text, but also to avoid
2510 a gcc error: the format attribute requires a string literal. */
2511 fprintf_unfiltered (gdb_stdlog
, "%s", text
);
2513 xfree (status_string
);
2515 ui_file_delete (tmp_stream
);
2518 /* Prepare and stabilize the inferior for detaching it. E.g.,
2519 detaching while a thread is displaced stepping is a recipe for
2520 crashing it, as nothing would readjust the PC out of the scratch
2524 prepare_for_detach (void)
2526 struct inferior
*inf
= current_inferior ();
2527 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
2528 struct cleanup
*old_chain_1
;
2529 struct displaced_step_inferior_state
*displaced
;
2531 displaced
= get_displaced_stepping_state (inf
->pid
);
2533 /* Is any thread of this process displaced stepping? If not,
2534 there's nothing else to do. */
2535 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
2539 fprintf_unfiltered (gdb_stdlog
,
2540 "displaced-stepping in-process while detaching");
2542 old_chain_1
= make_cleanup_restore_integer (&inf
->detaching
);
2545 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
2547 struct cleanup
*old_chain_2
;
2548 struct execution_control_state ecss
;
2549 struct execution_control_state
*ecs
;
2552 memset (ecs
, 0, sizeof (*ecs
));
2554 overlay_cache_invalid
= 1;
2556 /* We have to invalidate the registers BEFORE calling
2557 target_wait because they can be loaded from the target while
2558 in target_wait. This makes remote debugging a bit more
2559 efficient for those targets that provide critical registers
2560 as part of their normal status mechanism. */
2562 registers_changed ();
2564 if (deprecated_target_wait_hook
)
2565 ecs
->ptid
= deprecated_target_wait_hook (pid_ptid
, &ecs
->ws
, 0);
2567 ecs
->ptid
= target_wait (pid_ptid
, &ecs
->ws
, 0);
2570 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
2572 /* If an error happens while handling the event, propagate GDB's
2573 knowledge of the executing state to the frontend/user running
2575 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
2578 /* In non-stop mode, each thread is handled individually.
2579 Switch early, so the global state is set correctly for this
2582 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2583 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2584 context_switch (ecs
->ptid
);
2586 /* Now figure out what to do with the result of the result. */
2587 handle_inferior_event (ecs
);
2589 /* No error, don't finish the state yet. */
2590 discard_cleanups (old_chain_2
);
2592 /* Breakpoints and watchpoints are not installed on the target
2593 at this point, and signals are passed directly to the
2594 inferior, so this must mean the process is gone. */
2595 if (!ecs
->wait_some_more
)
2597 discard_cleanups (old_chain_1
);
2598 error (_("Program exited while detaching"));
2602 discard_cleanups (old_chain_1
);
2605 /* Wait for control to return from inferior to debugger.
2607 If inferior gets a signal, we may decide to start it up again
2608 instead of returning. That is why there is a loop in this function.
2609 When this function actually returns it means the inferior
2610 should be left stopped and GDB should read more commands. */
2613 wait_for_inferior (void)
2615 struct cleanup
*old_cleanups
;
2616 struct execution_control_state ecss
;
2617 struct execution_control_state
*ecs
;
2621 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
2624 make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup
, NULL
);
2627 memset (ecs
, 0, sizeof (*ecs
));
2629 /* We'll update this if & when we switch to a new thread. */
2630 previous_inferior_ptid
= inferior_ptid
;
2634 struct cleanup
*old_chain
;
2636 /* We have to invalidate the registers BEFORE calling target_wait
2637 because they can be loaded from the target while in target_wait.
2638 This makes remote debugging a bit more efficient for those
2639 targets that provide critical registers as part of their normal
2640 status mechanism. */
2642 overlay_cache_invalid
= 1;
2643 registers_changed ();
2645 if (deprecated_target_wait_hook
)
2646 ecs
->ptid
= deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, 0);
2648 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, 0);
2651 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2653 /* If an error happens while handling the event, propagate GDB's
2654 knowledge of the executing state to the frontend/user running
2656 old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2658 if (ecs
->ws
.kind
== TARGET_WAITKIND_SYSCALL_ENTRY
2659 || ecs
->ws
.kind
== TARGET_WAITKIND_SYSCALL_RETURN
)
2660 ecs
->ws
.value
.syscall_number
= UNKNOWN_SYSCALL
;
2662 /* Now figure out what to do with the result of the result. */
2663 handle_inferior_event (ecs
);
2665 /* No error, don't finish the state yet. */
2666 discard_cleanups (old_chain
);
2668 if (!ecs
->wait_some_more
)
2672 do_cleanups (old_cleanups
);
2675 /* Asynchronous version of wait_for_inferior. It is called by the
2676 event loop whenever a change of state is detected on the file
2677 descriptor corresponding to the target. It can be called more than
2678 once to complete a single execution command. In such cases we need
2679 to keep the state in a global variable ECSS. If it is the last time
2680 that this function is called for a single execution command, then
2681 report to the user that the inferior has stopped, and do the
2682 necessary cleanups. */
2685 fetch_inferior_event (void *client_data
)
2687 struct execution_control_state ecss
;
2688 struct execution_control_state
*ecs
= &ecss
;
2689 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
2690 struct cleanup
*ts_old_chain
;
2691 int was_sync
= sync_execution
;
2693 memset (ecs
, 0, sizeof (*ecs
));
2695 /* We'll update this if & when we switch to a new thread. */
2696 previous_inferior_ptid
= inferior_ptid
;
2698 /* We're handling a live event, so make sure we're doing live
2699 debugging. If we're looking at traceframes while the target is
2700 running, we're going to need to get back to that mode after
2701 handling the event. */
2704 make_cleanup_restore_current_traceframe ();
2705 set_current_traceframe (-1);
2709 /* In non-stop mode, the user/frontend should not notice a thread
2710 switch due to internal events. Make sure we reverse to the
2711 user selected thread and frame after handling the event and
2712 running any breakpoint commands. */
2713 make_cleanup_restore_current_thread ();
2715 /* We have to invalidate the registers BEFORE calling target_wait
2716 because they can be loaded from the target while in target_wait.
2717 This makes remote debugging a bit more efficient for those
2718 targets that provide critical registers as part of their normal
2719 status mechanism. */
2721 overlay_cache_invalid
= 1;
2722 registers_changed ();
2724 if (deprecated_target_wait_hook
)
2726 deprecated_target_wait_hook (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2728 ecs
->ptid
= target_wait (waiton_ptid
, &ecs
->ws
, TARGET_WNOHANG
);
2731 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
2734 && ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
2735 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2736 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
2737 /* In non-stop mode, each thread is handled individually. Switch
2738 early, so the global state is set correctly for this
2740 context_switch (ecs
->ptid
);
2742 /* If an error happens while handling the event, propagate GDB's
2743 knowledge of the executing state to the frontend/user running
2746 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
2748 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
2750 /* Now figure out what to do with the result of the result. */
2751 handle_inferior_event (ecs
);
2753 if (!ecs
->wait_some_more
)
2755 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
2757 delete_step_thread_step_resume_breakpoint ();
2759 /* We may not find an inferior if this was a process exit. */
2760 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
2763 if (target_has_execution
2764 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
2765 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
2766 && ecs
->event_thread
->step_multi
2767 && ecs
->event_thread
->control
.stop_step
)
2768 inferior_event_handler (INF_EXEC_CONTINUE
, NULL
);
2770 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2773 /* No error, don't finish the thread states yet. */
2774 discard_cleanups (ts_old_chain
);
2776 /* Revert thread and frame. */
2777 do_cleanups (old_chain
);
2779 /* If the inferior was in sync execution mode, and now isn't,
2780 restore the prompt. */
2781 if (was_sync
&& !sync_execution
)
2782 display_gdb_prompt (0);
2785 /* Record the frame and location we're currently stepping through. */
2787 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
2789 struct thread_info
*tp
= inferior_thread ();
2791 tp
->control
.step_frame_id
= get_frame_id (frame
);
2792 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
2794 tp
->current_symtab
= sal
.symtab
;
2795 tp
->current_line
= sal
.line
;
2798 /* Clear context switchable stepping state. */
2801 init_thread_stepping_state (struct thread_info
*tss
)
2803 tss
->stepping_over_breakpoint
= 0;
2804 tss
->step_after_step_resume_breakpoint
= 0;
2805 tss
->stepping_through_solib_after_catch
= 0;
2806 tss
->stepping_through_solib_catchpoints
= NULL
;
2809 /* Return the cached copy of the last pid/waitstatus returned by
2810 target_wait()/deprecated_target_wait_hook(). The data is actually
2811 cached by handle_inferior_event(), which gets called immediately
2812 after target_wait()/deprecated_target_wait_hook(). */
2815 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
2817 *ptidp
= target_last_wait_ptid
;
2818 *status
= target_last_waitstatus
;
2822 nullify_last_target_wait_ptid (void)
2824 target_last_wait_ptid
= minus_one_ptid
;
2827 /* Switch thread contexts. */
2830 context_switch (ptid_t ptid
)
2834 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
2835 target_pid_to_str (inferior_ptid
));
2836 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
2837 target_pid_to_str (ptid
));
2840 switch_to_thread (ptid
);
2844 adjust_pc_after_break (struct execution_control_state
*ecs
)
2846 struct regcache
*regcache
;
2847 struct gdbarch
*gdbarch
;
2848 struct address_space
*aspace
;
2849 CORE_ADDR breakpoint_pc
;
2851 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
2852 we aren't, just return.
2854 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
2855 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
2856 implemented by software breakpoints should be handled through the normal
2859 NOTE drow/2004-01-31: On some targets, breakpoints may generate
2860 different signals (SIGILL or SIGEMT for instance), but it is less
2861 clear where the PC is pointing afterwards. It may not match
2862 gdbarch_decr_pc_after_break. I don't know any specific target that
2863 generates these signals at breakpoints (the code has been in GDB since at
2864 least 1992) so I can not guess how to handle them here.
2866 In earlier versions of GDB, a target with
2867 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
2868 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
2869 target with both of these set in GDB history, and it seems unlikely to be
2870 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
2872 if (ecs
->ws
.kind
!= TARGET_WAITKIND_STOPPED
)
2875 if (ecs
->ws
.value
.sig
!= TARGET_SIGNAL_TRAP
)
2878 /* In reverse execution, when a breakpoint is hit, the instruction
2879 under it has already been de-executed. The reported PC always
2880 points at the breakpoint address, so adjusting it further would
2881 be wrong. E.g., consider this case on a decr_pc_after_break == 1
2884 B1 0x08000000 : INSN1
2885 B2 0x08000001 : INSN2
2887 PC -> 0x08000003 : INSN4
2889 Say you're stopped at 0x08000003 as above. Reverse continuing
2890 from that point should hit B2 as below. Reading the PC when the
2891 SIGTRAP is reported should read 0x08000001 and INSN2 should have
2892 been de-executed already.
2894 B1 0x08000000 : INSN1
2895 B2 PC -> 0x08000001 : INSN2
2899 We can't apply the same logic as for forward execution, because
2900 we would wrongly adjust the PC to 0x08000000, since there's a
2901 breakpoint at PC - 1. We'd then report a hit on B1, although
2902 INSN1 hadn't been de-executed yet. Doing nothing is the correct
2904 if (execution_direction
== EXEC_REVERSE
)
2907 /* If this target does not decrement the PC after breakpoints, then
2908 we have nothing to do. */
2909 regcache
= get_thread_regcache (ecs
->ptid
);
2910 gdbarch
= get_regcache_arch (regcache
);
2911 if (gdbarch_decr_pc_after_break (gdbarch
) == 0)
2914 aspace
= get_regcache_aspace (regcache
);
2916 /* Find the location where (if we've hit a breakpoint) the
2917 breakpoint would be. */
2918 breakpoint_pc
= regcache_read_pc (regcache
)
2919 - gdbarch_decr_pc_after_break (gdbarch
);
2921 /* Check whether there actually is a software breakpoint inserted at
2924 If in non-stop mode, a race condition is possible where we've
2925 removed a breakpoint, but stop events for that breakpoint were
2926 already queued and arrive later. To suppress those spurious
2927 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
2928 and retire them after a number of stop events are reported. */
2929 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
2930 || (non_stop
&& moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
2932 struct cleanup
*old_cleanups
= NULL
;
2935 old_cleanups
= record_gdb_operation_disable_set ();
2937 /* When using hardware single-step, a SIGTRAP is reported for both
2938 a completed single-step and a software breakpoint. Need to
2939 differentiate between the two, as the latter needs adjusting
2940 but the former does not.
2942 The SIGTRAP can be due to a completed hardware single-step only if
2943 - we didn't insert software single-step breakpoints
2944 - the thread to be examined is still the current thread
2945 - this thread is currently being stepped
2947 If any of these events did not occur, we must have stopped due
2948 to hitting a software breakpoint, and have to back up to the
2951 As a special case, we could have hardware single-stepped a
2952 software breakpoint. In this case (prev_pc == breakpoint_pc),
2953 we also need to back up to the breakpoint address. */
2955 if (singlestep_breakpoints_inserted_p
2956 || !ptid_equal (ecs
->ptid
, inferior_ptid
)
2957 || !currently_stepping (ecs
->event_thread
)
2958 || ecs
->event_thread
->prev_pc
== breakpoint_pc
)
2959 regcache_write_pc (regcache
, breakpoint_pc
);
2962 do_cleanups (old_cleanups
);
2967 init_infwait_state (void)
2969 waiton_ptid
= pid_to_ptid (-1);
2970 infwait_state
= infwait_normal_state
;
2974 error_is_running (void)
2976 error (_("Cannot execute this command while "
2977 "the selected thread is running."));
2981 ensure_not_running (void)
2983 if (is_running (inferior_ptid
))
2984 error_is_running ();
2988 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
2990 for (frame
= get_prev_frame (frame
);
2992 frame
= get_prev_frame (frame
))
2994 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
2996 if (get_frame_type (frame
) != INLINE_FRAME
)
3003 /* Auxiliary function that handles syscall entry/return events.
3004 It returns 1 if the inferior should keep going (and GDB
3005 should ignore the event), or 0 if the event deserves to be
3009 handle_syscall_event (struct execution_control_state
*ecs
)
3011 struct regcache
*regcache
;
3012 struct gdbarch
*gdbarch
;
3015 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3016 context_switch (ecs
->ptid
);
3018 regcache
= get_thread_regcache (ecs
->ptid
);
3019 gdbarch
= get_regcache_arch (regcache
);
3020 syscall_number
= gdbarch_get_syscall_number (gdbarch
, ecs
->ptid
);
3021 stop_pc
= regcache_read_pc (regcache
);
3023 target_last_waitstatus
.value
.syscall_number
= syscall_number
;
3025 if (catch_syscall_enabled () > 0
3026 && catching_syscall_number (syscall_number
) > 0)
3029 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
3032 ecs
->event_thread
->control
.stop_bpstat
3033 = bpstat_stop_status (get_regcache_aspace (regcache
),
3034 stop_pc
, ecs
->ptid
);
3036 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3038 if (!ecs
->random_signal
)
3040 /* Catchpoint hit. */
3041 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_TRAP
;
3046 /* If no catchpoint triggered for this, then keep going. */
3047 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
3052 /* Given an execution control state that has been freshly filled in
3053 by an event from the inferior, figure out what it means and take
3054 appropriate action. */
3057 handle_inferior_event (struct execution_control_state
*ecs
)
3059 struct frame_info
*frame
;
3060 struct gdbarch
*gdbarch
;
3061 int sw_single_step_trap_p
= 0;
3062 int stopped_by_watchpoint
;
3063 int stepped_after_stopped_by_watchpoint
= 0;
3064 struct symtab_and_line stop_pc_sal
;
3065 enum stop_kind stop_soon
;
3067 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
3069 /* We had an event in the inferior, but we are not interested in
3070 handling it at this level. The lower layers have already
3071 done what needs to be done, if anything.
3073 One of the possible circumstances for this is when the
3074 inferior produces output for the console. The inferior has
3075 not stopped, and we are ignoring the event. Another possible
3076 circumstance is any event which the lower level knows will be
3077 reported multiple times without an intervening resume. */
3079 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
3080 prepare_to_wait (ecs
);
3084 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3085 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
3087 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
3090 stop_soon
= inf
->control
.stop_soon
;
3093 stop_soon
= NO_STOP_QUIETLY
;
3095 /* Cache the last pid/waitstatus. */
3096 target_last_wait_ptid
= ecs
->ptid
;
3097 target_last_waitstatus
= ecs
->ws
;
3099 /* Always clear state belonging to the previous time we stopped. */
3100 stop_stack_dummy
= STOP_NONE
;
3102 /* If it's a new process, add it to the thread database. */
3104 ecs
->new_thread_event
= (!ptid_equal (ecs
->ptid
, inferior_ptid
)
3105 && !ptid_equal (ecs
->ptid
, minus_one_ptid
)
3106 && !in_thread_list (ecs
->ptid
));
3108 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
3109 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
&& ecs
->new_thread_event
)
3110 add_thread (ecs
->ptid
);
3112 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3114 /* Dependent on valid ECS->EVENT_THREAD. */
3115 adjust_pc_after_break (ecs
);
3117 /* Dependent on the current PC value modified by adjust_pc_after_break. */
3118 reinit_frame_cache ();
3120 breakpoint_retire_moribund ();
3122 /* First, distinguish signals caused by the debugger from signals
3123 that have to do with the program's own actions. Note that
3124 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
3125 on the operating system version. Here we detect when a SIGILL or
3126 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
3127 something similar for SIGSEGV, since a SIGSEGV will be generated
3128 when we're trying to execute a breakpoint instruction on a
3129 non-executable stack. This happens for call dummy breakpoints
3130 for architectures like SPARC that place call dummies on the
3132 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
3133 && (ecs
->ws
.value
.sig
== TARGET_SIGNAL_ILL
3134 || ecs
->ws
.value
.sig
== TARGET_SIGNAL_SEGV
3135 || ecs
->ws
.value
.sig
== TARGET_SIGNAL_EMT
))
3137 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3139 if (breakpoint_inserted_here_p (get_regcache_aspace (regcache
),
3140 regcache_read_pc (regcache
)))
3143 fprintf_unfiltered (gdb_stdlog
,
3144 "infrun: Treating signal as SIGTRAP\n");
3145 ecs
->ws
.value
.sig
= TARGET_SIGNAL_TRAP
;
3149 /* Mark the non-executing threads accordingly. In all-stop, all
3150 threads of all processes are stopped when we get any event
3151 reported. In non-stop mode, only the event thread stops. If
3152 we're handling a process exit in non-stop mode, there's nothing
3153 to do, as threads of the dead process are gone, and threads of
3154 any other process were left running. */
3156 set_executing (minus_one_ptid
, 0);
3157 else if (ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
3158 && ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
)
3159 set_executing (inferior_ptid
, 0);
3161 switch (infwait_state
)
3163 case infwait_thread_hop_state
:
3165 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_thread_hop_state\n");
3168 case infwait_normal_state
:
3170 fprintf_unfiltered (gdb_stdlog
, "infrun: infwait_normal_state\n");
3173 case infwait_step_watch_state
:
3175 fprintf_unfiltered (gdb_stdlog
,
3176 "infrun: infwait_step_watch_state\n");
3178 stepped_after_stopped_by_watchpoint
= 1;
3181 case infwait_nonstep_watch_state
:
3183 fprintf_unfiltered (gdb_stdlog
,
3184 "infrun: infwait_nonstep_watch_state\n");
3185 insert_breakpoints ();
3187 /* FIXME-maybe: is this cleaner than setting a flag? Does it
3188 handle things like signals arriving and other things happening
3189 in combination correctly? */
3190 stepped_after_stopped_by_watchpoint
= 1;
3194 internal_error (__FILE__
, __LINE__
, _("bad switch"));
3197 infwait_state
= infwait_normal_state
;
3198 waiton_ptid
= pid_to_ptid (-1);
3200 switch (ecs
->ws
.kind
)
3202 case TARGET_WAITKIND_LOADED
:
3204 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
3205 /* Ignore gracefully during startup of the inferior, as it might
3206 be the shell which has just loaded some objects, otherwise
3207 add the symbols for the newly loaded objects. Also ignore at
3208 the beginning of an attach or remote session; we will query
3209 the full list of libraries once the connection is
3211 if (stop_soon
== NO_STOP_QUIETLY
)
3213 /* Check for any newly added shared libraries if we're
3214 supposed to be adding them automatically. Switch
3215 terminal for any messages produced by
3216 breakpoint_re_set. */
3217 target_terminal_ours_for_output ();
3218 /* NOTE: cagney/2003-11-25: Make certain that the target
3219 stack's section table is kept up-to-date. Architectures,
3220 (e.g., PPC64), use the section table to perform
3221 operations such as address => section name and hence
3222 require the table to contain all sections (including
3223 those found in shared libraries). */
3225 SOLIB_ADD (NULL
, 0, ¤t_target
, auto_solib_add
);
3227 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
3229 target_terminal_inferior ();
3231 /* If requested, stop when the dynamic linker notifies
3232 gdb of events. This allows the user to get control
3233 and place breakpoints in initializer routines for
3234 dynamically loaded objects (among other things). */
3235 if (stop_on_solib_events
)
3237 /* Make sure we print "Stopped due to solib-event" in
3239 stop_print_frame
= 1;
3241 stop_stepping (ecs
);
3245 /* NOTE drow/2007-05-11: This might be a good place to check
3246 for "catch load". */
3249 /* If we are skipping through a shell, or through shared library
3250 loading that we aren't interested in, resume the program. If
3251 we're running the program normally, also resume. But stop if
3252 we're attaching or setting up a remote connection. */
3253 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
3255 /* Loading of shared libraries might have changed breakpoint
3256 addresses. Make sure new breakpoints are inserted. */
3257 if (stop_soon
== NO_STOP_QUIETLY
3258 && !breakpoints_always_inserted_mode ())
3259 insert_breakpoints ();
3260 resume (0, TARGET_SIGNAL_0
);
3261 prepare_to_wait (ecs
);
3267 case TARGET_WAITKIND_SPURIOUS
:
3269 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
3270 resume (0, TARGET_SIGNAL_0
);
3271 prepare_to_wait (ecs
);
3274 case TARGET_WAITKIND_EXITED
:
3276 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXITED\n");
3277 inferior_ptid
= ecs
->ptid
;
3278 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3279 set_current_program_space (current_inferior ()->pspace
);
3280 handle_vfork_child_exec_or_exit (0);
3281 target_terminal_ours (); /* Must do this before mourn anyway. */
3282 print_exited_reason (ecs
->ws
.value
.integer
);
3284 /* Record the exit code in the convenience variable $_exitcode, so
3285 that the user can inspect this again later. */
3286 set_internalvar_integer (lookup_internalvar ("_exitcode"),
3287 (LONGEST
) ecs
->ws
.value
.integer
);
3288 gdb_flush (gdb_stdout
);
3289 target_mourn_inferior ();
3290 singlestep_breakpoints_inserted_p
= 0;
3291 cancel_single_step_breakpoints ();
3292 stop_print_frame
= 0;
3293 stop_stepping (ecs
);
3296 case TARGET_WAITKIND_SIGNALLED
:
3298 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SIGNALLED\n");
3299 inferior_ptid
= ecs
->ptid
;
3300 set_current_inferior (find_inferior_pid (ptid_get_pid (ecs
->ptid
)));
3301 set_current_program_space (current_inferior ()->pspace
);
3302 handle_vfork_child_exec_or_exit (0);
3303 stop_print_frame
= 0;
3304 target_terminal_ours (); /* Must do this before mourn anyway. */
3306 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
3307 reach here unless the inferior is dead. However, for years
3308 target_kill() was called here, which hints that fatal signals aren't
3309 really fatal on some systems. If that's true, then some changes
3311 target_mourn_inferior ();
3313 print_signal_exited_reason (ecs
->ws
.value
.sig
);
3314 singlestep_breakpoints_inserted_p
= 0;
3315 cancel_single_step_breakpoints ();
3316 stop_stepping (ecs
);
3319 /* The following are the only cases in which we keep going;
3320 the above cases end in a continue or goto. */
3321 case TARGET_WAITKIND_FORKED
:
3322 case TARGET_WAITKIND_VFORKED
:
3324 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
3326 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3328 context_switch (ecs
->ptid
);
3329 reinit_frame_cache ();
3332 /* Immediately detach breakpoints from the child before there's
3333 any chance of letting the user delete breakpoints from the
3334 breakpoint lists. If we don't do this early, it's easy to
3335 leave left over traps in the child, vis: "break foo; catch
3336 fork; c; <fork>; del; c; <child calls foo>". We only follow
3337 the fork on the last `continue', and by that time the
3338 breakpoint at "foo" is long gone from the breakpoint table.
3339 If we vforked, then we don't need to unpatch here, since both
3340 parent and child are sharing the same memory pages; we'll
3341 need to unpatch at follow/detach time instead to be certain
3342 that new breakpoints added between catchpoint hit time and
3343 vfork follow are detached. */
3344 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
3346 int child_pid
= ptid_get_pid (ecs
->ws
.value
.related_pid
);
3348 /* This won't actually modify the breakpoint list, but will
3349 physically remove the breakpoints from the child. */
3350 detach_breakpoints (child_pid
);
3353 if (singlestep_breakpoints_inserted_p
)
3355 /* Pull the single step breakpoints out of the target. */
3356 remove_single_step_breakpoints ();
3357 singlestep_breakpoints_inserted_p
= 0;
3360 /* In case the event is caught by a catchpoint, remember that
3361 the event is to be followed at the next resume of the thread,
3362 and not immediately. */
3363 ecs
->event_thread
->pending_follow
= ecs
->ws
;
3365 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3367 ecs
->event_thread
->control
.stop_bpstat
3368 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3369 stop_pc
, ecs
->ptid
);
3371 /* Note that we're interested in knowing the bpstat actually
3372 causes a stop, not just if it may explain the signal.
3373 Software watchpoints, for example, always appear in the
3376 = !bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
);
3378 /* If no catchpoint triggered for this, then keep going. */
3379 if (ecs
->random_signal
)
3385 = (follow_fork_mode_string
== follow_fork_mode_child
);
3387 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
3389 should_resume
= follow_fork ();
3392 child
= ecs
->ws
.value
.related_pid
;
3394 /* In non-stop mode, also resume the other branch. */
3395 if (non_stop
&& !detach_fork
)
3398 switch_to_thread (parent
);
3400 switch_to_thread (child
);
3402 ecs
->event_thread
= inferior_thread ();
3403 ecs
->ptid
= inferior_ptid
;
3408 switch_to_thread (child
);
3410 switch_to_thread (parent
);
3412 ecs
->event_thread
= inferior_thread ();
3413 ecs
->ptid
= inferior_ptid
;
3418 stop_stepping (ecs
);
3421 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_TRAP
;
3422 goto process_event_stop_test
;
3424 case TARGET_WAITKIND_VFORK_DONE
:
3425 /* Done with the shared memory region. Re-insert breakpoints in
3426 the parent, and keep going. */
3429 fprintf_unfiltered (gdb_stdlog
,
3430 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
3432 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3433 context_switch (ecs
->ptid
);
3435 current_inferior ()->waiting_for_vfork_done
= 0;
3436 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
3437 /* This also takes care of reinserting breakpoints in the
3438 previously locked inferior. */
3442 case TARGET_WAITKIND_EXECD
:
3444 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
3446 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3448 context_switch (ecs
->ptid
);
3449 reinit_frame_cache ();
3452 singlestep_breakpoints_inserted_p
= 0;
3453 cancel_single_step_breakpoints ();
3455 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3457 /* Do whatever is necessary to the parent branch of the vfork. */
3458 handle_vfork_child_exec_or_exit (1);
3460 /* This causes the eventpoints and symbol table to be reset.
3461 Must do this now, before trying to determine whether to
3463 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
3465 ecs
->event_thread
->control
.stop_bpstat
3466 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
3467 stop_pc
, ecs
->ptid
);
3469 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
);
3471 /* Note that this may be referenced from inside
3472 bpstat_stop_status above, through inferior_has_execd. */
3473 xfree (ecs
->ws
.value
.execd_pathname
);
3474 ecs
->ws
.value
.execd_pathname
= NULL
;
3476 /* If no catchpoint triggered for this, then keep going. */
3477 if (ecs
->random_signal
)
3479 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
3483 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_TRAP
;
3484 goto process_event_stop_test
;
3486 /* Be careful not to try to gather much state about a thread
3487 that's in a syscall. It's frequently a losing proposition. */
3488 case TARGET_WAITKIND_SYSCALL_ENTRY
:
3490 fprintf_unfiltered (gdb_stdlog
,
3491 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
3492 /* Getting the current syscall number. */
3493 if (handle_syscall_event (ecs
) != 0)
3495 goto process_event_stop_test
;
3497 /* Before examining the threads further, step this thread to
3498 get it entirely out of the syscall. (We get notice of the
3499 event when the thread is just on the verge of exiting a
3500 syscall. Stepping one instruction seems to get it back
3502 case TARGET_WAITKIND_SYSCALL_RETURN
:
3504 fprintf_unfiltered (gdb_stdlog
,
3505 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
3506 if (handle_syscall_event (ecs
) != 0)
3508 goto process_event_stop_test
;
3510 case TARGET_WAITKIND_STOPPED
:
3512 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
3513 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
3516 case TARGET_WAITKIND_NO_HISTORY
:
3517 /* Reverse execution: target ran out of history info. */
3518 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3519 print_no_history_reason ();
3520 stop_stepping (ecs
);
3524 if (ecs
->new_thread_event
)
3527 /* Non-stop assumes that the target handles adding new threads
3528 to the thread list. */
3529 internal_error (__FILE__
, __LINE__
,
3530 "targets should add new threads to the thread "
3531 "list themselves in non-stop mode.");
3533 /* We may want to consider not doing a resume here in order to
3534 give the user a chance to play with the new thread. It might
3535 be good to make that a user-settable option. */
3537 /* At this point, all threads are stopped (happens automatically
3538 in either the OS or the native code). Therefore we need to
3539 continue all threads in order to make progress. */
3541 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3542 context_switch (ecs
->ptid
);
3543 target_resume (RESUME_ALL
, 0, TARGET_SIGNAL_0
);
3544 prepare_to_wait (ecs
);
3548 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
)
3550 /* Do we need to clean up the state of a thread that has
3551 completed a displaced single-step? (Doing so usually affects
3552 the PC, so do it here, before we set stop_pc.) */
3553 displaced_step_fixup (ecs
->ptid
,
3554 ecs
->event_thread
->suspend
.stop_signal
);
3556 /* If we either finished a single-step or hit a breakpoint, but
3557 the user wanted this thread to be stopped, pretend we got a
3558 SIG0 (generic unsignaled stop). */
3560 if (ecs
->event_thread
->stop_requested
3561 && ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
)
3562 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
3565 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
3569 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
3570 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
3571 struct cleanup
*old_chain
= save_inferior_ptid ();
3573 inferior_ptid
= ecs
->ptid
;
3575 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
3576 paddress (gdbarch
, stop_pc
));
3577 if (target_stopped_by_watchpoint ())
3581 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
3583 if (target_stopped_data_address (¤t_target
, &addr
))
3584 fprintf_unfiltered (gdb_stdlog
,
3585 "infrun: stopped data address = %s\n",
3586 paddress (gdbarch
, addr
));
3588 fprintf_unfiltered (gdb_stdlog
,
3589 "infrun: (no data address available)\n");
3592 do_cleanups (old_chain
);
3595 if (stepping_past_singlestep_breakpoint
)
3597 gdb_assert (singlestep_breakpoints_inserted_p
);
3598 gdb_assert (ptid_equal (singlestep_ptid
, ecs
->ptid
));
3599 gdb_assert (!ptid_equal (singlestep_ptid
, saved_singlestep_ptid
));
3601 stepping_past_singlestep_breakpoint
= 0;
3603 /* We've either finished single-stepping past the single-step
3604 breakpoint, or stopped for some other reason. It would be nice if
3605 we could tell, but we can't reliably. */
3606 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
)
3609 fprintf_unfiltered (gdb_stdlog
,
3610 "infrun: stepping_past_"
3611 "singlestep_breakpoint\n");
3612 /* Pull the single step breakpoints out of the target. */
3613 remove_single_step_breakpoints ();
3614 singlestep_breakpoints_inserted_p
= 0;
3616 ecs
->random_signal
= 0;
3617 ecs
->event_thread
->control
.trap_expected
= 0;
3619 context_switch (saved_singlestep_ptid
);
3620 if (deprecated_context_hook
)
3621 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3623 resume (1, TARGET_SIGNAL_0
);
3624 prepare_to_wait (ecs
);
3629 if (!ptid_equal (deferred_step_ptid
, null_ptid
))
3631 /* In non-stop mode, there's never a deferred_step_ptid set. */
3632 gdb_assert (!non_stop
);
3634 /* If we stopped for some other reason than single-stepping, ignore
3635 the fact that we were supposed to switch back. */
3636 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
)
3639 fprintf_unfiltered (gdb_stdlog
,
3640 "infrun: handling deferred step\n");
3642 /* Pull the single step breakpoints out of the target. */
3643 if (singlestep_breakpoints_inserted_p
)
3645 remove_single_step_breakpoints ();
3646 singlestep_breakpoints_inserted_p
= 0;
3649 /* Note: We do not call context_switch at this point, as the
3650 context is already set up for stepping the original thread. */
3651 switch_to_thread (deferred_step_ptid
);
3652 deferred_step_ptid
= null_ptid
;
3653 /* Suppress spurious "Switching to ..." message. */
3654 previous_inferior_ptid
= inferior_ptid
;
3656 resume (1, TARGET_SIGNAL_0
);
3657 prepare_to_wait (ecs
);
3661 deferred_step_ptid
= null_ptid
;
3664 /* See if a thread hit a thread-specific breakpoint that was meant for
3665 another thread. If so, then step that thread past the breakpoint,
3668 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
)
3670 int thread_hop_needed
= 0;
3671 struct address_space
*aspace
=
3672 get_regcache_aspace (get_thread_regcache (ecs
->ptid
));
3674 /* Check if a regular breakpoint has been hit before checking
3675 for a potential single step breakpoint. Otherwise, GDB will
3676 not see this breakpoint hit when stepping onto breakpoints. */
3677 if (regular_breakpoint_inserted_here_p (aspace
, stop_pc
))
3679 ecs
->random_signal
= 0;
3680 if (!breakpoint_thread_match (aspace
, stop_pc
, ecs
->ptid
))
3681 thread_hop_needed
= 1;
3683 else if (singlestep_breakpoints_inserted_p
)
3685 /* We have not context switched yet, so this should be true
3686 no matter which thread hit the singlestep breakpoint. */
3687 gdb_assert (ptid_equal (inferior_ptid
, singlestep_ptid
));
3689 fprintf_unfiltered (gdb_stdlog
, "infrun: software single step "
3691 target_pid_to_str (ecs
->ptid
));
3693 ecs
->random_signal
= 0;
3694 /* The call to in_thread_list is necessary because PTIDs sometimes
3695 change when we go from single-threaded to multi-threaded. If
3696 the singlestep_ptid is still in the list, assume that it is
3697 really different from ecs->ptid. */
3698 if (!ptid_equal (singlestep_ptid
, ecs
->ptid
)
3699 && in_thread_list (singlestep_ptid
))
3701 /* If the PC of the thread we were trying to single-step
3702 has changed, discard this event (which we were going
3703 to ignore anyway), and pretend we saw that thread
3704 trap. This prevents us continuously moving the
3705 single-step breakpoint forward, one instruction at a
3706 time. If the PC has changed, then the thread we were
3707 trying to single-step has trapped or been signalled,
3708 but the event has not been reported to GDB yet.
3710 There might be some cases where this loses signal
3711 information, if a signal has arrived at exactly the
3712 same time that the PC changed, but this is the best
3713 we can do with the information available. Perhaps we
3714 should arrange to report all events for all threads
3715 when they stop, or to re-poll the remote looking for
3716 this particular thread (i.e. temporarily enable
3719 CORE_ADDR new_singlestep_pc
3720 = regcache_read_pc (get_thread_regcache (singlestep_ptid
));
3722 if (new_singlestep_pc
!= singlestep_pc
)
3724 enum target_signal stop_signal
;
3727 fprintf_unfiltered (gdb_stdlog
, "infrun: unexpected thread,"
3728 " but expected thread advanced also\n");
3730 /* The current context still belongs to
3731 singlestep_ptid. Don't swap here, since that's
3732 the context we want to use. Just fudge our
3733 state and continue. */
3734 stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
3735 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
3736 ecs
->ptid
= singlestep_ptid
;
3737 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
3738 ecs
->event_thread
->suspend
.stop_signal
= stop_signal
;
3739 stop_pc
= new_singlestep_pc
;
3744 fprintf_unfiltered (gdb_stdlog
,
3745 "infrun: unexpected thread\n");
3747 thread_hop_needed
= 1;
3748 stepping_past_singlestep_breakpoint
= 1;
3749 saved_singlestep_ptid
= singlestep_ptid
;
3754 if (thread_hop_needed
)
3756 struct regcache
*thread_regcache
;
3757 int remove_status
= 0;
3760 fprintf_unfiltered (gdb_stdlog
, "infrun: thread_hop_needed\n");
3762 /* Switch context before touching inferior memory, the
3763 previous thread may have exited. */
3764 if (!ptid_equal (inferior_ptid
, ecs
->ptid
))
3765 context_switch (ecs
->ptid
);
3767 /* Saw a breakpoint, but it was hit by the wrong thread.
3770 if (singlestep_breakpoints_inserted_p
)
3772 /* Pull the single step breakpoints out of the target. */
3773 remove_single_step_breakpoints ();
3774 singlestep_breakpoints_inserted_p
= 0;
3777 /* If the arch can displace step, don't remove the
3779 thread_regcache
= get_thread_regcache (ecs
->ptid
);
3780 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
3781 remove_status
= remove_breakpoints ();
3783 /* Did we fail to remove breakpoints? If so, try
3784 to set the PC past the bp. (There's at least
3785 one situation in which we can fail to remove
3786 the bp's: On HP-UX's that use ttrace, we can't
3787 change the address space of a vforking child
3788 process until the child exits (well, okay, not
3789 then either :-) or execs. */
3790 if (remove_status
!= 0)
3791 error (_("Cannot step over breakpoint hit in wrong thread"));
3796 /* Only need to require the next event from this
3797 thread in all-stop mode. */
3798 waiton_ptid
= ecs
->ptid
;
3799 infwait_state
= infwait_thread_hop_state
;
3802 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3807 else if (singlestep_breakpoints_inserted_p
)
3809 sw_single_step_trap_p
= 1;
3810 ecs
->random_signal
= 0;
3814 ecs
->random_signal
= 1;
3816 /* See if something interesting happened to the non-current thread. If
3817 so, then switch to that thread. */
3818 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
3821 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
3823 context_switch (ecs
->ptid
);
3825 if (deprecated_context_hook
)
3826 deprecated_context_hook (pid_to_thread_id (ecs
->ptid
));
3829 /* At this point, get hold of the now-current thread's frame. */
3830 frame
= get_current_frame ();
3831 gdbarch
= get_frame_arch (frame
);
3833 if (singlestep_breakpoints_inserted_p
)
3835 /* Pull the single step breakpoints out of the target. */
3836 remove_single_step_breakpoints ();
3837 singlestep_breakpoints_inserted_p
= 0;
3840 if (stepped_after_stopped_by_watchpoint
)
3841 stopped_by_watchpoint
= 0;
3843 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
3845 /* If necessary, step over this watchpoint. We'll be back to display
3847 if (stopped_by_watchpoint
3848 && (target_have_steppable_watchpoint
3849 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
3851 /* At this point, we are stopped at an instruction which has
3852 attempted to write to a piece of memory under control of
3853 a watchpoint. The instruction hasn't actually executed
3854 yet. If we were to evaluate the watchpoint expression
3855 now, we would get the old value, and therefore no change
3856 would seem to have occurred.
3858 In order to make watchpoints work `right', we really need
3859 to complete the memory write, and then evaluate the
3860 watchpoint expression. We do this by single-stepping the
3863 It may not be necessary to disable the watchpoint to stop over
3864 it. For example, the PA can (with some kernel cooperation)
3865 single step over a watchpoint without disabling the watchpoint.
3867 It is far more common to need to disable a watchpoint to step
3868 the inferior over it. If we have non-steppable watchpoints,
3869 we must disable the current watchpoint; it's simplest to
3870 disable all watchpoints and breakpoints. */
3873 if (!target_have_steppable_watchpoint
)
3875 remove_breakpoints ();
3876 /* See comment in resume why we need to stop bypassing signals
3877 while breakpoints have been removed. */
3878 target_pass_signals (0, NULL
);
3881 hw_step
= maybe_software_singlestep (gdbarch
, stop_pc
);
3882 target_resume (ecs
->ptid
, hw_step
, TARGET_SIGNAL_0
);
3883 waiton_ptid
= ecs
->ptid
;
3884 if (target_have_steppable_watchpoint
)
3885 infwait_state
= infwait_step_watch_state
;
3887 infwait_state
= infwait_nonstep_watch_state
;
3888 prepare_to_wait (ecs
);
3892 ecs
->stop_func_start
= 0;
3893 ecs
->stop_func_end
= 0;
3894 ecs
->stop_func_name
= 0;
3895 /* Don't care about return value; stop_func_start and stop_func_name
3896 will both be 0 if it doesn't work. */
3897 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
3898 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
3899 ecs
->stop_func_start
3900 += gdbarch_deprecated_function_start_offset (gdbarch
);
3901 ecs
->event_thread
->stepping_over_breakpoint
= 0;
3902 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
3903 ecs
->event_thread
->control
.stop_step
= 0;
3904 stop_print_frame
= 1;
3905 ecs
->random_signal
= 0;
3906 stopped_by_random_signal
= 0;
3908 /* Hide inlined functions starting here, unless we just performed stepi or
3909 nexti. After stepi and nexti, always show the innermost frame (not any
3910 inline function call sites). */
3911 if (ecs
->event_thread
->control
.step_range_end
!= 1)
3912 skip_inline_frames (ecs
->ptid
);
3914 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
3915 && ecs
->event_thread
->control
.trap_expected
3916 && gdbarch_single_step_through_delay_p (gdbarch
)
3917 && currently_stepping (ecs
->event_thread
))
3919 /* We're trying to step off a breakpoint. Turns out that we're
3920 also on an instruction that needs to be stepped multiple
3921 times before it's been fully executing. E.g., architectures
3922 with a delay slot. It needs to be stepped twice, once for
3923 the instruction and once for the delay slot. */
3924 int step_through_delay
3925 = gdbarch_single_step_through_delay (gdbarch
, frame
);
3927 if (debug_infrun
&& step_through_delay
)
3928 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
3929 if (ecs
->event_thread
->control
.step_range_end
== 0
3930 && step_through_delay
)
3932 /* The user issued a continue when stopped at a breakpoint.
3933 Set up for another trap and get out of here. */
3934 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3938 else if (step_through_delay
)
3940 /* The user issued a step when stopped at a breakpoint.
3941 Maybe we should stop, maybe we should not - the delay
3942 slot *might* correspond to a line of source. In any
3943 case, don't decide that here, just set
3944 ecs->stepping_over_breakpoint, making sure we
3945 single-step again before breakpoints are re-inserted. */
3946 ecs
->event_thread
->stepping_over_breakpoint
= 1;
3950 /* Look at the cause of the stop, and decide what to do.
3951 The alternatives are:
3952 1) stop_stepping and return; to really stop and return to the debugger,
3953 2) keep_going and return to start up again
3954 (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
3955 3) set ecs->random_signal to 1, and the decision between 1 and 2
3956 will be made according to the signal handling tables. */
3958 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
3959 || stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_NO_SIGSTOP
3960 || stop_soon
== STOP_QUIETLY_REMOTE
)
3962 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
3966 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
3967 stop_print_frame
= 0;
3968 stop_stepping (ecs
);
3972 /* This is originated from start_remote(), start_inferior() and
3973 shared libraries hook functions. */
3974 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
3977 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
3978 stop_stepping (ecs
);
3982 /* This originates from attach_command(). We need to overwrite
3983 the stop_signal here, because some kernels don't ignore a
3984 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
3985 See more comments in inferior.h. On the other hand, if we
3986 get a non-SIGSTOP, report it to the user - assume the backend
3987 will handle the SIGSTOP if it should show up later.
3989 Also consider that the attach is complete when we see a
3990 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
3991 target extended-remote report it instead of a SIGSTOP
3992 (e.g. gdbserver). We already rely on SIGTRAP being our
3993 signal, so this is no exception.
3995 Also consider that the attach is complete when we see a
3996 TARGET_SIGNAL_0. In non-stop mode, GDB will explicitly tell
3997 the target to stop all threads of the inferior, in case the
3998 low level attach operation doesn't stop them implicitly. If
3999 they weren't stopped implicitly, then the stub will report a
4000 TARGET_SIGNAL_0, meaning: stopped for no particular reason
4001 other than GDB's request. */
4002 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4003 && (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_STOP
4004 || ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
4005 || ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_0
))
4007 stop_stepping (ecs
);
4008 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
4012 /* See if there is a breakpoint at the current PC. */
4013 ecs
->event_thread
->control
.stop_bpstat
4014 = bpstat_stop_status (get_regcache_aspace (get_current_regcache ()),
4015 stop_pc
, ecs
->ptid
);
4017 /* Following in case break condition called a
4019 stop_print_frame
= 1;
4021 /* This is where we handle "moribund" watchpoints. Unlike
4022 software breakpoints traps, hardware watchpoint traps are
4023 always distinguishable from random traps. If no high-level
4024 watchpoint is associated with the reported stop data address
4025 anymore, then the bpstat does not explain the signal ---
4026 simply make sure to ignore it if `stopped_by_watchpoint' is
4030 && ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
4031 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4032 && stopped_by_watchpoint
)
4033 fprintf_unfiltered (gdb_stdlog
,
4034 "infrun: no user watchpoint explains "
4035 "watchpoint SIGTRAP, ignoring\n");
4037 /* NOTE: cagney/2003-03-29: These two checks for a random signal
4038 at one stage in the past included checks for an inferior
4039 function call's call dummy's return breakpoint. The original
4040 comment, that went with the test, read:
4042 ``End of a stack dummy. Some systems (e.g. Sony news) give
4043 another signal besides SIGTRAP, so check here as well as
4046 If someone ever tries to get call dummys on a
4047 non-executable stack to work (where the target would stop
4048 with something like a SIGSEGV), then those tests might need
4049 to be re-instated. Given, however, that the tests were only
4050 enabled when momentary breakpoints were not being used, I
4051 suspect that it won't be the case.
4053 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
4054 be necessary for call dummies on a non-executable stack on
4057 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
)
4059 = !(bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
)
4060 || stopped_by_watchpoint
4061 || ecs
->event_thread
->control
.trap_expected
4062 || (ecs
->event_thread
->control
.step_range_end
4063 && (ecs
->event_thread
->control
.step_resume_breakpoint
4067 ecs
->random_signal
= !bpstat_explains_signal
4068 (ecs
->event_thread
->control
.stop_bpstat
);
4069 if (!ecs
->random_signal
)
4070 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_TRAP
;
4074 /* When we reach this point, we've pretty much decided
4075 that the reason for stopping must've been a random
4076 (unexpected) signal. */
4079 ecs
->random_signal
= 1;
4081 process_event_stop_test
:
4083 /* Re-fetch current thread's frame in case we did a
4084 "goto process_event_stop_test" above. */
4085 frame
= get_current_frame ();
4086 gdbarch
= get_frame_arch (frame
);
4088 /* For the program's own signals, act according to
4089 the signal handling tables. */
4091 if (ecs
->random_signal
)
4093 /* Signal not for debugging purposes. */
4095 struct inferior
*inf
= find_inferior_pid (ptid_get_pid (ecs
->ptid
));
4098 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal %d\n",
4099 ecs
->event_thread
->suspend
.stop_signal
);
4101 stopped_by_random_signal
= 1;
4103 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
4106 target_terminal_ours_for_output ();
4107 print_signal_received_reason
4108 (ecs
->event_thread
->suspend
.stop_signal
);
4110 /* Always stop on signals if we're either just gaining control
4111 of the program, or the user explicitly requested this thread
4112 to remain stopped. */
4113 if (stop_soon
!= NO_STOP_QUIETLY
4114 || ecs
->event_thread
->stop_requested
4116 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
4118 stop_stepping (ecs
);
4121 /* If not going to stop, give terminal back
4122 if we took it away. */
4124 target_terminal_inferior ();
4126 /* Clear the signal if it should not be passed. */
4127 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
4128 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
4130 if (ecs
->event_thread
->prev_pc
== stop_pc
4131 && ecs
->event_thread
->control
.trap_expected
4132 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4134 /* We were just starting a new sequence, attempting to
4135 single-step off of a breakpoint and expecting a SIGTRAP.
4136 Instead this signal arrives. This signal will take us out
4137 of the stepping range so GDB needs to remember to, when
4138 the signal handler returns, resume stepping off that
4140 /* To simplify things, "continue" is forced to use the same
4141 code paths as single-step - set a breakpoint at the
4142 signal return address and then, once hit, step off that
4145 fprintf_unfiltered (gdb_stdlog
,
4146 "infrun: signal arrived while stepping over "
4149 insert_step_resume_breakpoint_at_frame (frame
);
4150 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
4151 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4152 ecs
->event_thread
->control
.trap_expected
= 0;
4157 if (ecs
->event_thread
->control
.step_range_end
!= 0
4158 && ecs
->event_thread
->suspend
.stop_signal
!= TARGET_SIGNAL_0
4159 && (ecs
->event_thread
->control
.step_range_start
<= stop_pc
4160 && stop_pc
< ecs
->event_thread
->control
.step_range_end
)
4161 && frame_id_eq (get_stack_frame_id (frame
),
4162 ecs
->event_thread
->control
.step_stack_frame_id
)
4163 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
4165 /* The inferior is about to take a signal that will take it
4166 out of the single step range. Set a breakpoint at the
4167 current PC (which is presumably where the signal handler
4168 will eventually return) and then allow the inferior to
4171 Note that this is only needed for a signal delivered
4172 while in the single-step range. Nested signals aren't a
4173 problem as they eventually all return. */
4175 fprintf_unfiltered (gdb_stdlog
,
4176 "infrun: signal may take us out of "
4177 "single-step range\n");
4179 insert_step_resume_breakpoint_at_frame (frame
);
4180 /* Reset trap_expected to ensure breakpoints are re-inserted. */
4181 ecs
->event_thread
->control
.trap_expected
= 0;
4186 /* Note: step_resume_breakpoint may be non-NULL. This occures
4187 when either there's a nested signal, or when there's a
4188 pending signal enabled just as the signal handler returns
4189 (leaving the inferior at the step-resume-breakpoint without
4190 actually executing it). Either way continue until the
4191 breakpoint is really hit. */
4196 /* Handle cases caused by hitting a breakpoint. */
4198 CORE_ADDR jmp_buf_pc
;
4199 struct bpstat_what what
;
4201 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
4203 if (what
.call_dummy
)
4205 stop_stack_dummy
= what
.call_dummy
;
4208 /* If we hit an internal event that triggers symbol changes, the
4209 current frame will be invalidated within bpstat_what (e.g., if
4210 we hit an internal solib event). Re-fetch it. */
4211 frame
= get_current_frame ();
4212 gdbarch
= get_frame_arch (frame
);
4214 switch (what
.main_action
)
4216 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
4217 /* If we hit the breakpoint at longjmp while stepping, we
4218 install a momentary breakpoint at the target of the
4222 fprintf_unfiltered (gdb_stdlog
,
4223 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
4225 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4227 if (what
.is_longjmp
)
4229 if (!gdbarch_get_longjmp_target_p (gdbarch
)
4230 || !gdbarch_get_longjmp_target (gdbarch
,
4231 frame
, &jmp_buf_pc
))
4234 fprintf_unfiltered (gdb_stdlog
,
4235 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
4236 "(!gdbarch_get_longjmp_target)\n");
4241 /* We're going to replace the current step-resume breakpoint
4242 with a longjmp-resume breakpoint. */
4243 delete_step_resume_breakpoint (ecs
->event_thread
);
4245 /* Insert a breakpoint at resume address. */
4246 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
4250 struct symbol
*func
= get_frame_function (frame
);
4253 check_exception_resume (ecs
, frame
, func
);
4258 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
4260 fprintf_unfiltered (gdb_stdlog
,
4261 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
4263 if (what
.is_longjmp
)
4265 gdb_assert (ecs
->event_thread
->control
.step_resume_breakpoint
4267 delete_step_resume_breakpoint (ecs
->event_thread
);
4271 /* There are several cases to consider.
4273 1. The initiating frame no longer exists. In this case
4274 we must stop, because the exception has gone too far.
4276 2. The initiating frame exists, and is the same as the
4277 current frame. We stop, because the exception has been
4280 3. The initiating frame exists and is different from
4281 the current frame. This means the exception has been
4282 caught beneath the initiating frame, so keep going. */
4283 struct frame_info
*init_frame
4284 = frame_find_by_id (ecs
->event_thread
->initiating_frame
);
4286 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
4288 delete_exception_resume_breakpoint (ecs
->event_thread
);
4292 struct frame_id current_id
4293 = get_frame_id (get_current_frame ());
4294 if (frame_id_eq (current_id
,
4295 ecs
->event_thread
->initiating_frame
))
4297 /* Case 2. Fall through. */
4307 /* For Cases 1 and 2, remove the step-resume breakpoint,
4309 delete_step_resume_breakpoint (ecs
->event_thread
);
4312 ecs
->event_thread
->control
.stop_step
= 1;
4313 print_end_stepping_range_reason ();
4314 stop_stepping (ecs
);
4317 case BPSTAT_WHAT_SINGLE
:
4319 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
4320 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4321 /* Still need to check other stuff, at least the case
4322 where we are stepping and step out of the right range. */
4325 case BPSTAT_WHAT_STOP_NOISY
:
4327 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
4328 stop_print_frame
= 1;
4330 /* We are about to nuke the step_resume_breakpointt via the
4331 cleanup chain, so no need to worry about it here. */
4333 stop_stepping (ecs
);
4336 case BPSTAT_WHAT_STOP_SILENT
:
4338 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
4339 stop_print_frame
= 0;
4341 /* We are about to nuke the step_resume_breakpoin via the
4342 cleanup chain, so no need to worry about it here. */
4344 stop_stepping (ecs
);
4347 case BPSTAT_WHAT_STEP_RESUME
:
4349 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
4351 delete_step_resume_breakpoint (ecs
->event_thread
);
4352 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
4354 /* Back when the step-resume breakpoint was inserted, we
4355 were trying to single-step off a breakpoint. Go back
4357 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
4358 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4362 if (stop_pc
== ecs
->stop_func_start
4363 && execution_direction
== EXEC_REVERSE
)
4365 /* We are stepping over a function call in reverse, and
4366 just hit the step-resume breakpoint at the start
4367 address of the function. Go back to single-stepping,
4368 which should take us back to the function call. */
4369 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4375 case BPSTAT_WHAT_KEEP_CHECKING
:
4380 /* We come here if we hit a breakpoint but should not
4381 stop for it. Possibly we also were stepping
4382 and should stop for that. So fall through and
4383 test for stepping. But, if not stepping,
4386 /* In all-stop mode, if we're currently stepping but have stopped in
4387 some other thread, we need to switch back to the stepped thread. */
4390 struct thread_info
*tp
;
4392 tp
= iterate_over_threads (currently_stepping_or_nexting_callback
,
4396 /* However, if the current thread is blocked on some internal
4397 breakpoint, and we simply need to step over that breakpoint
4398 to get it going again, do that first. */
4399 if ((ecs
->event_thread
->control
.trap_expected
4400 && ecs
->event_thread
->suspend
.stop_signal
!= TARGET_SIGNAL_TRAP
)
4401 || ecs
->event_thread
->stepping_over_breakpoint
)
4407 /* If the stepping thread exited, then don't try to switch
4408 back and resume it, which could fail in several different
4409 ways depending on the target. Instead, just keep going.
4411 We can find a stepping dead thread in the thread list in
4414 - The target supports thread exit events, and when the
4415 target tries to delete the thread from the thread list,
4416 inferior_ptid pointed at the exiting thread. In such
4417 case, calling delete_thread does not really remove the
4418 thread from the list; instead, the thread is left listed,
4419 with 'exited' state.
4421 - The target's debug interface does not support thread
4422 exit events, and so we have no idea whatsoever if the
4423 previously stepping thread is still alive. For that
4424 reason, we need to synchronously query the target
4426 if (is_exited (tp
->ptid
)
4427 || !target_thread_alive (tp
->ptid
))
4430 fprintf_unfiltered (gdb_stdlog
,
4431 "infrun: not switching back to "
4432 "stepped thread, it has vanished\n");
4434 delete_thread (tp
->ptid
);
4439 /* Otherwise, we no longer expect a trap in the current thread.
4440 Clear the trap_expected flag before switching back -- this is
4441 what keep_going would do as well, if we called it. */
4442 ecs
->event_thread
->control
.trap_expected
= 0;
4445 fprintf_unfiltered (gdb_stdlog
,
4446 "infrun: switching back to stepped thread\n");
4448 ecs
->event_thread
= tp
;
4449 ecs
->ptid
= tp
->ptid
;
4450 context_switch (ecs
->ptid
);
4456 /* Are we stepping to get the inferior out of the dynamic linker's
4457 hook (and possibly the dld itself) after catching a shlib
4459 if (ecs
->event_thread
->stepping_through_solib_after_catch
)
4461 #if defined(SOLIB_ADD)
4462 /* Have we reached our destination? If not, keep going. */
4463 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs
->ptid
), stop_pc
))
4466 fprintf_unfiltered (gdb_stdlog
,
4467 "infrun: stepping in dynamic linker\n");
4468 ecs
->event_thread
->stepping_over_breakpoint
= 1;
4474 fprintf_unfiltered (gdb_stdlog
, "infrun: step past dynamic linker\n");
4475 /* Else, stop and report the catchpoint(s) whose triggering
4476 caused us to begin stepping. */
4477 ecs
->event_thread
->stepping_through_solib_after_catch
= 0;
4478 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
4479 ecs
->event_thread
->control
.stop_bpstat
4480 = bpstat_copy (ecs
->event_thread
->stepping_through_solib_catchpoints
);
4481 bpstat_clear (&ecs
->event_thread
->stepping_through_solib_catchpoints
);
4482 stop_print_frame
= 1;
4483 stop_stepping (ecs
);
4487 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
4490 fprintf_unfiltered (gdb_stdlog
,
4491 "infrun: step-resume breakpoint is inserted\n");
4493 /* Having a step-resume breakpoint overrides anything
4494 else having to do with stepping commands until
4495 that breakpoint is reached. */
4500 if (ecs
->event_thread
->control
.step_range_end
== 0)
4503 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
4504 /* Likewise if we aren't even stepping. */
4509 /* Re-fetch current thread's frame in case the code above caused
4510 the frame cache to be re-initialized, making our FRAME variable
4511 a dangling pointer. */
4512 frame
= get_current_frame ();
4513 gdbarch
= get_frame_arch (frame
);
4515 /* If stepping through a line, keep going if still within it.
4517 Note that step_range_end is the address of the first instruction
4518 beyond the step range, and NOT the address of the last instruction
4521 Note also that during reverse execution, we may be stepping
4522 through a function epilogue and therefore must detect when
4523 the current-frame changes in the middle of a line. */
4525 if (stop_pc
>= ecs
->event_thread
->control
.step_range_start
4526 && stop_pc
< ecs
->event_thread
->control
.step_range_end
4527 && (execution_direction
!= EXEC_REVERSE
4528 || frame_id_eq (get_frame_id (frame
),
4529 ecs
->event_thread
->control
.step_frame_id
)))
4533 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
4534 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
4535 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
4537 /* When stepping backward, stop at beginning of line range
4538 (unless it's the function entry point, in which case
4539 keep going back to the call point). */
4540 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
4541 && stop_pc
!= ecs
->stop_func_start
4542 && execution_direction
== EXEC_REVERSE
)
4544 ecs
->event_thread
->control
.stop_step
= 1;
4545 print_end_stepping_range_reason ();
4546 stop_stepping (ecs
);
4554 /* We stepped out of the stepping range. */
4556 /* If we are stepping at the source level and entered the runtime
4557 loader dynamic symbol resolution code...
4559 EXEC_FORWARD: we keep on single stepping until we exit the run
4560 time loader code and reach the callee's address.
4562 EXEC_REVERSE: we've already executed the callee (backward), and
4563 the runtime loader code is handled just like any other
4564 undebuggable function call. Now we need only keep stepping
4565 backward through the trampoline code, and that's handled further
4566 down, so there is nothing for us to do here. */
4568 if (execution_direction
!= EXEC_REVERSE
4569 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4570 && in_solib_dynsym_resolve_code (stop_pc
))
4572 CORE_ADDR pc_after_resolver
=
4573 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
4576 fprintf_unfiltered (gdb_stdlog
,
4577 "infrun: stepped into dynsym resolve code\n");
4579 if (pc_after_resolver
)
4581 /* Set up a step-resume breakpoint at the address
4582 indicated by SKIP_SOLIB_RESOLVER. */
4583 struct symtab_and_line sr_sal
;
4586 sr_sal
.pc
= pc_after_resolver
;
4587 sr_sal
.pspace
= get_frame_program_space (frame
);
4589 insert_step_resume_breakpoint_at_sal (gdbarch
,
4590 sr_sal
, null_frame_id
);
4597 if (ecs
->event_thread
->control
.step_range_end
!= 1
4598 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4599 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4600 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
4603 fprintf_unfiltered (gdb_stdlog
,
4604 "infrun: stepped into signal trampoline\n");
4605 /* The inferior, while doing a "step" or "next", has ended up in
4606 a signal trampoline (either by a signal being delivered or by
4607 the signal handler returning). Just single-step until the
4608 inferior leaves the trampoline (either by calling the handler
4614 /* Check for subroutine calls. The check for the current frame
4615 equalling the step ID is not necessary - the check of the
4616 previous frame's ID is sufficient - but it is a common case and
4617 cheaper than checking the previous frame's ID.
4619 NOTE: frame_id_eq will never report two invalid frame IDs as
4620 being equal, so to get into this block, both the current and
4621 previous frame must have valid frame IDs. */
4622 /* The outer_frame_id check is a heuristic to detect stepping
4623 through startup code. If we step over an instruction which
4624 sets the stack pointer from an invalid value to a valid value,
4625 we may detect that as a subroutine call from the mythical
4626 "outermost" function. This could be fixed by marking
4627 outermost frames as !stack_p,code_p,special_p. Then the
4628 initial outermost frame, before sp was valid, would
4629 have code_addr == &_start. See the comment in frame_id_eq
4631 if (!frame_id_eq (get_stack_frame_id (frame
),
4632 ecs
->event_thread
->control
.step_stack_frame_id
)
4633 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
4634 ecs
->event_thread
->control
.step_stack_frame_id
)
4635 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
4637 || step_start_function
!= find_pc_function (stop_pc
))))
4639 CORE_ADDR real_stop_pc
;
4642 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
4644 if ((ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
4645 || ((ecs
->event_thread
->control
.step_range_end
== 1)
4646 && in_prologue (gdbarch
, ecs
->event_thread
->prev_pc
,
4647 ecs
->stop_func_start
)))
4649 /* I presume that step_over_calls is only 0 when we're
4650 supposed to be stepping at the assembly language level
4651 ("stepi"). Just stop. */
4652 /* Also, maybe we just did a "nexti" inside a prolog, so we
4653 thought it was a subroutine call but it was not. Stop as
4655 /* And this works the same backward as frontward. MVS */
4656 ecs
->event_thread
->control
.stop_step
= 1;
4657 print_end_stepping_range_reason ();
4658 stop_stepping (ecs
);
4662 /* Reverse stepping through solib trampolines. */
4664 if (execution_direction
== EXEC_REVERSE
4665 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
4666 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4667 || (ecs
->stop_func_start
== 0
4668 && in_solib_dynsym_resolve_code (stop_pc
))))
4670 /* Any solib trampoline code can be handled in reverse
4671 by simply continuing to single-step. We have already
4672 executed the solib function (backwards), and a few
4673 steps will take us back through the trampoline to the
4679 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4681 /* We're doing a "next".
4683 Normal (forward) execution: set a breakpoint at the
4684 callee's return address (the address at which the caller
4687 Reverse (backward) execution. set the step-resume
4688 breakpoint at the start of the function that we just
4689 stepped into (backwards), and continue to there. When we
4690 get there, we'll need to single-step back to the caller. */
4692 if (execution_direction
== EXEC_REVERSE
)
4694 struct symtab_and_line sr_sal
;
4696 /* Normal function call return (static or dynamic). */
4698 sr_sal
.pc
= ecs
->stop_func_start
;
4699 sr_sal
.pspace
= get_frame_program_space (frame
);
4700 insert_step_resume_breakpoint_at_sal (gdbarch
,
4701 sr_sal
, null_frame_id
);
4704 insert_step_resume_breakpoint_at_caller (frame
);
4710 /* If we are in a function call trampoline (a stub between the
4711 calling routine and the real function), locate the real
4712 function. That's what tells us (a) whether we want to step
4713 into it at all, and (b) what prologue we want to run to the
4714 end of, if we do step into it. */
4715 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
4716 if (real_stop_pc
== 0)
4717 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4718 if (real_stop_pc
!= 0)
4719 ecs
->stop_func_start
= real_stop_pc
;
4721 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
4723 struct symtab_and_line sr_sal
;
4726 sr_sal
.pc
= ecs
->stop_func_start
;
4727 sr_sal
.pspace
= get_frame_program_space (frame
);
4729 insert_step_resume_breakpoint_at_sal (gdbarch
,
4730 sr_sal
, null_frame_id
);
4735 /* If we have line number information for the function we are
4736 thinking of stepping into, step into it.
4738 If there are several symtabs at that PC (e.g. with include
4739 files), just want to know whether *any* of them have line
4740 numbers. find_pc_line handles this. */
4742 struct symtab_and_line tmp_sal
;
4744 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
4745 if (tmp_sal
.line
!= 0)
4747 if (execution_direction
== EXEC_REVERSE
)
4748 handle_step_into_function_backward (gdbarch
, ecs
);
4750 handle_step_into_function (gdbarch
, ecs
);
4755 /* If we have no line number and the step-stop-if-no-debug is
4756 set, we stop the step so that the user has a chance to switch
4757 in assembly mode. */
4758 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4759 && step_stop_if_no_debug
)
4761 ecs
->event_thread
->control
.stop_step
= 1;
4762 print_end_stepping_range_reason ();
4763 stop_stepping (ecs
);
4767 if (execution_direction
== EXEC_REVERSE
)
4769 /* Set a breakpoint at callee's start address.
4770 From there we can step once and be back in the caller. */
4771 struct symtab_and_line sr_sal
;
4774 sr_sal
.pc
= ecs
->stop_func_start
;
4775 sr_sal
.pspace
= get_frame_program_space (frame
);
4776 insert_step_resume_breakpoint_at_sal (gdbarch
,
4777 sr_sal
, null_frame_id
);
4780 /* Set a breakpoint at callee's return address (the address
4781 at which the caller will resume). */
4782 insert_step_resume_breakpoint_at_caller (frame
);
4788 /* Reverse stepping through solib trampolines. */
4790 if (execution_direction
== EXEC_REVERSE
4791 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
4793 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
4794 || (ecs
->stop_func_start
== 0
4795 && in_solib_dynsym_resolve_code (stop_pc
)))
4797 /* Any solib trampoline code can be handled in reverse
4798 by simply continuing to single-step. We have already
4799 executed the solib function (backwards), and a few
4800 steps will take us back through the trampoline to the
4805 else if (in_solib_dynsym_resolve_code (stop_pc
))
4807 /* Stepped backward into the solib dynsym resolver.
4808 Set a breakpoint at its start and continue, then
4809 one more step will take us out. */
4810 struct symtab_and_line sr_sal
;
4813 sr_sal
.pc
= ecs
->stop_func_start
;
4814 sr_sal
.pspace
= get_frame_program_space (frame
);
4815 insert_step_resume_breakpoint_at_sal (gdbarch
,
4816 sr_sal
, null_frame_id
);
4822 /* If we're in the return path from a shared library trampoline,
4823 we want to proceed through the trampoline when stepping. */
4824 if (gdbarch_in_solib_return_trampoline (gdbarch
,
4825 stop_pc
, ecs
->stop_func_name
))
4827 /* Determine where this trampoline returns. */
4828 CORE_ADDR real_stop_pc
;
4830 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
4833 fprintf_unfiltered (gdb_stdlog
,
4834 "infrun: stepped into solib return tramp\n");
4836 /* Only proceed through if we know where it's going. */
4839 /* And put the step-breakpoint there and go until there. */
4840 struct symtab_and_line sr_sal
;
4842 init_sal (&sr_sal
); /* initialize to zeroes */
4843 sr_sal
.pc
= real_stop_pc
;
4844 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
4845 sr_sal
.pspace
= get_frame_program_space (frame
);
4847 /* Do not specify what the fp should be when we stop since
4848 on some machines the prologue is where the new fp value
4850 insert_step_resume_breakpoint_at_sal (gdbarch
,
4851 sr_sal
, null_frame_id
);
4853 /* Restart without fiddling with the step ranges or
4860 stop_pc_sal
= find_pc_line (stop_pc
, 0);
4862 /* NOTE: tausq/2004-05-24: This if block used to be done before all
4863 the trampoline processing logic, however, there are some trampolines
4864 that have no names, so we should do trampoline handling first. */
4865 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
4866 && ecs
->stop_func_name
== NULL
4867 && stop_pc_sal
.line
== 0)
4870 fprintf_unfiltered (gdb_stdlog
,
4871 "infrun: stepped into undebuggable function\n");
4873 /* The inferior just stepped into, or returned to, an
4874 undebuggable function (where there is no debugging information
4875 and no line number corresponding to the address where the
4876 inferior stopped). Since we want to skip this kind of code,
4877 we keep going until the inferior returns from this
4878 function - unless the user has asked us not to (via
4879 set step-mode) or we no longer know how to get back
4880 to the call site. */
4881 if (step_stop_if_no_debug
4882 || !frame_id_p (frame_unwind_caller_id (frame
)))
4884 /* If we have no line number and the step-stop-if-no-debug
4885 is set, we stop the step so that the user has a chance to
4886 switch in assembly mode. */
4887 ecs
->event_thread
->control
.stop_step
= 1;
4888 print_end_stepping_range_reason ();
4889 stop_stepping (ecs
);
4894 /* Set a breakpoint at callee's return address (the address
4895 at which the caller will resume). */
4896 insert_step_resume_breakpoint_at_caller (frame
);
4902 if (ecs
->event_thread
->control
.step_range_end
== 1)
4904 /* It is stepi or nexti. We always want to stop stepping after
4907 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
4908 ecs
->event_thread
->control
.stop_step
= 1;
4909 print_end_stepping_range_reason ();
4910 stop_stepping (ecs
);
4914 if (stop_pc_sal
.line
== 0)
4916 /* We have no line number information. That means to stop
4917 stepping (does this always happen right after one instruction,
4918 when we do "s" in a function with no line numbers,
4919 or can this happen as a result of a return or longjmp?). */
4921 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
4922 ecs
->event_thread
->control
.stop_step
= 1;
4923 print_end_stepping_range_reason ();
4924 stop_stepping (ecs
);
4928 /* Look for "calls" to inlined functions, part one. If the inline
4929 frame machinery detected some skipped call sites, we have entered
4930 a new inline function. */
4932 if (frame_id_eq (get_frame_id (get_current_frame ()),
4933 ecs
->event_thread
->control
.step_frame_id
)
4934 && inline_skipped_frames (ecs
->ptid
))
4936 struct symtab_and_line call_sal
;
4939 fprintf_unfiltered (gdb_stdlog
,
4940 "infrun: stepped into inlined function\n");
4942 find_frame_sal (get_current_frame (), &call_sal
);
4944 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
4946 /* For "step", we're going to stop. But if the call site
4947 for this inlined function is on the same source line as
4948 we were previously stepping, go down into the function
4949 first. Otherwise stop at the call site. */
4951 if (call_sal
.line
== ecs
->event_thread
->current_line
4952 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4953 step_into_inline_frame (ecs
->ptid
);
4955 ecs
->event_thread
->control
.stop_step
= 1;
4956 print_end_stepping_range_reason ();
4957 stop_stepping (ecs
);
4962 /* For "next", we should stop at the call site if it is on a
4963 different source line. Otherwise continue through the
4964 inlined function. */
4965 if (call_sal
.line
== ecs
->event_thread
->current_line
4966 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
4970 ecs
->event_thread
->control
.stop_step
= 1;
4971 print_end_stepping_range_reason ();
4972 stop_stepping (ecs
);
4978 /* Look for "calls" to inlined functions, part two. If we are still
4979 in the same real function we were stepping through, but we have
4980 to go further up to find the exact frame ID, we are stepping
4981 through a more inlined call beyond its call site. */
4983 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
4984 && !frame_id_eq (get_frame_id (get_current_frame ()),
4985 ecs
->event_thread
->control
.step_frame_id
)
4986 && stepped_in_from (get_current_frame (),
4987 ecs
->event_thread
->control
.step_frame_id
))
4990 fprintf_unfiltered (gdb_stdlog
,
4991 "infrun: stepping through inlined function\n");
4993 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
4997 ecs
->event_thread
->control
.stop_step
= 1;
4998 print_end_stepping_range_reason ();
4999 stop_stepping (ecs
);
5004 if ((stop_pc
== stop_pc_sal
.pc
)
5005 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
5006 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
5008 /* We are at the start of a different line. So stop. Note that
5009 we don't stop if we step into the middle of a different line.
5010 That is said to make things like for (;;) statements work
5013 fprintf_unfiltered (gdb_stdlog
,
5014 "infrun: stepped to a different line\n");
5015 ecs
->event_thread
->control
.stop_step
= 1;
5016 print_end_stepping_range_reason ();
5017 stop_stepping (ecs
);
5021 /* We aren't done stepping.
5023 Optimize by setting the stepping range to the line.
5024 (We might not be in the original line, but if we entered a
5025 new line in mid-statement, we continue stepping. This makes
5026 things like for(;;) statements work better.) */
5028 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
5029 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
5030 set_step_info (frame
, stop_pc_sal
);
5033 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
5037 /* Is thread TP in the middle of single-stepping? */
5040 currently_stepping (struct thread_info
*tp
)
5042 return ((tp
->control
.step_range_end
5043 && tp
->control
.step_resume_breakpoint
== NULL
)
5044 || tp
->control
.trap_expected
5045 || tp
->stepping_through_solib_after_catch
5046 || bpstat_should_step ());
5049 /* Returns true if any thread *but* the one passed in "data" is in the
5050 middle of stepping or of handling a "next". */
5053 currently_stepping_or_nexting_callback (struct thread_info
*tp
, void *data
)
5058 return (tp
->control
.step_range_end
5059 || tp
->control
.trap_expected
5060 || tp
->stepping_through_solib_after_catch
);
5063 /* Inferior has stepped into a subroutine call with source code that
5064 we should not step over. Do step to the first line of code in
5068 handle_step_into_function (struct gdbarch
*gdbarch
,
5069 struct execution_control_state
*ecs
)
5072 struct symtab_and_line stop_func_sal
, sr_sal
;
5074 s
= find_pc_symtab (stop_pc
);
5075 if (s
&& s
->language
!= language_asm
)
5076 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5077 ecs
->stop_func_start
);
5079 stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
5080 /* Use the step_resume_break to step until the end of the prologue,
5081 even if that involves jumps (as it seems to on the vax under
5083 /* If the prologue ends in the middle of a source line, continue to
5084 the end of that source line (if it is still within the function).
5085 Otherwise, just go to end of prologue. */
5086 if (stop_func_sal
.end
5087 && stop_func_sal
.pc
!= ecs
->stop_func_start
5088 && stop_func_sal
.end
< ecs
->stop_func_end
)
5089 ecs
->stop_func_start
= stop_func_sal
.end
;
5091 /* Architectures which require breakpoint adjustment might not be able
5092 to place a breakpoint at the computed address. If so, the test
5093 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
5094 ecs->stop_func_start to an address at which a breakpoint may be
5095 legitimately placed.
5097 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
5098 made, GDB will enter an infinite loop when stepping through
5099 optimized code consisting of VLIW instructions which contain
5100 subinstructions corresponding to different source lines. On
5101 FR-V, it's not permitted to place a breakpoint on any but the
5102 first subinstruction of a VLIW instruction. When a breakpoint is
5103 set, GDB will adjust the breakpoint address to the beginning of
5104 the VLIW instruction. Thus, we need to make the corresponding
5105 adjustment here when computing the stop address. */
5107 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
5109 ecs
->stop_func_start
5110 = gdbarch_adjust_breakpoint_address (gdbarch
,
5111 ecs
->stop_func_start
);
5114 if (ecs
->stop_func_start
== stop_pc
)
5116 /* We are already there: stop now. */
5117 ecs
->event_thread
->control
.stop_step
= 1;
5118 print_end_stepping_range_reason ();
5119 stop_stepping (ecs
);
5124 /* Put the step-breakpoint there and go until there. */
5125 init_sal (&sr_sal
); /* initialize to zeroes */
5126 sr_sal
.pc
= ecs
->stop_func_start
;
5127 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
5128 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
5130 /* Do not specify what the fp should be when we stop since on
5131 some machines the prologue is where the new fp value is
5133 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
5135 /* And make sure stepping stops right away then. */
5136 ecs
->event_thread
->control
.step_range_end
5137 = ecs
->event_thread
->control
.step_range_start
;
5142 /* Inferior has stepped backward into a subroutine call with source
5143 code that we should not step over. Do step to the beginning of the
5144 last line of code in it. */
5147 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
5148 struct execution_control_state
*ecs
)
5151 struct symtab_and_line stop_func_sal
;
5153 s
= find_pc_symtab (stop_pc
);
5154 if (s
&& s
->language
!= language_asm
)
5155 ecs
->stop_func_start
= gdbarch_skip_prologue (gdbarch
,
5156 ecs
->stop_func_start
);
5158 stop_func_sal
= find_pc_line (stop_pc
, 0);
5160 /* OK, we're just going to keep stepping here. */
5161 if (stop_func_sal
.pc
== stop_pc
)
5163 /* We're there already. Just stop stepping now. */
5164 ecs
->event_thread
->control
.stop_step
= 1;
5165 print_end_stepping_range_reason ();
5166 stop_stepping (ecs
);
5170 /* Else just reset the step range and keep going.
5171 No step-resume breakpoint, they don't work for
5172 epilogues, which can have multiple entry paths. */
5173 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
5174 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
5180 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
5181 This is used to both functions and to skip over code. */
5184 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
5185 struct symtab_and_line sr_sal
,
5186 struct frame_id sr_id
)
5188 /* There should never be more than one step-resume or longjmp-resume
5189 breakpoint per thread, so we should never be setting a new
5190 step_resume_breakpoint when one is already active. */
5191 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5194 fprintf_unfiltered (gdb_stdlog
,
5195 "infrun: inserting step-resume breakpoint at %s\n",
5196 paddress (gdbarch
, sr_sal
.pc
));
5198 inferior_thread ()->control
.step_resume_breakpoint
5199 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, bp_step_resume
);
5202 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
5203 to skip a potential signal handler.
5205 This is called with the interrupted function's frame. The signal
5206 handler, when it returns, will resume the interrupted function at
5210 insert_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
5212 struct symtab_and_line sr_sal
;
5213 struct gdbarch
*gdbarch
;
5215 gdb_assert (return_frame
!= NULL
);
5216 init_sal (&sr_sal
); /* initialize to zeros */
5218 gdbarch
= get_frame_arch (return_frame
);
5219 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
5220 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5221 sr_sal
.pspace
= get_frame_program_space (return_frame
);
5223 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5224 get_stack_frame_id (return_frame
));
5227 /* Similar to insert_step_resume_breakpoint_at_frame, except
5228 but a breakpoint at the previous frame's PC. This is used to
5229 skip a function after stepping into it (for "next" or if the called
5230 function has no debugging information).
5232 The current function has almost always been reached by single
5233 stepping a call or return instruction. NEXT_FRAME belongs to the
5234 current function, and the breakpoint will be set at the caller's
5237 This is a separate function rather than reusing
5238 insert_step_resume_breakpoint_at_frame in order to avoid
5239 get_prev_frame, which may stop prematurely (see the implementation
5240 of frame_unwind_caller_id for an example). */
5243 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
5245 struct symtab_and_line sr_sal
;
5246 struct gdbarch
*gdbarch
;
5248 /* We shouldn't have gotten here if we don't know where the call site
5250 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
5252 init_sal (&sr_sal
); /* initialize to zeros */
5254 gdbarch
= frame_unwind_caller_arch (next_frame
);
5255 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
5256 frame_unwind_caller_pc (next_frame
));
5257 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
5258 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
5260 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
5261 frame_unwind_caller_id (next_frame
));
5264 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
5265 new breakpoint at the target of a jmp_buf. The handling of
5266 longjmp-resume uses the same mechanisms used for handling
5267 "step-resume" breakpoints. */
5270 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
5272 /* There should never be more than one step-resume or longjmp-resume
5273 breakpoint per thread, so we should never be setting a new
5274 longjmp_resume_breakpoint when one is already active. */
5275 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
5278 fprintf_unfiltered (gdb_stdlog
,
5279 "infrun: inserting longjmp-resume breakpoint at %s\n",
5280 paddress (gdbarch
, pc
));
5282 inferior_thread ()->control
.step_resume_breakpoint
=
5283 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
);
5286 /* Insert an exception resume breakpoint. TP is the thread throwing
5287 the exception. The block B is the block of the unwinder debug hook
5288 function. FRAME is the frame corresponding to the call to this
5289 function. SYM is the symbol of the function argument holding the
5290 target PC of the exception. */
5293 insert_exception_resume_breakpoint (struct thread_info
*tp
,
5295 struct frame_info
*frame
,
5298 struct gdb_exception e
;
5300 /* We want to ignore errors here. */
5301 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5303 struct symbol
*vsym
;
5304 struct value
*value
;
5306 struct breakpoint
*bp
;
5308 vsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (sym
), b
, VAR_DOMAIN
, NULL
);
5309 value
= read_var_value (vsym
, frame
);
5310 /* If the value was optimized out, revert to the old behavior. */
5311 if (! value_optimized_out (value
))
5313 handler
= value_as_address (value
);
5316 fprintf_unfiltered (gdb_stdlog
,
5317 "infrun: exception resume at %lx\n",
5318 (unsigned long) handler
);
5320 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
5321 handler
, bp_exception_resume
);
5322 bp
->thread
= tp
->num
;
5323 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
5328 /* This is called when an exception has been intercepted. Check to
5329 see whether the exception's destination is of interest, and if so,
5330 set an exception resume breakpoint there. */
5333 check_exception_resume (struct execution_control_state
*ecs
,
5334 struct frame_info
*frame
, struct symbol
*func
)
5336 struct gdb_exception e
;
5338 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5341 struct dict_iterator iter
;
5345 /* The exception breakpoint is a thread-specific breakpoint on
5346 the unwinder's debug hook, declared as:
5348 void _Unwind_DebugHook (void *cfa, void *handler);
5350 The CFA argument indicates the frame to which control is
5351 about to be transferred. HANDLER is the destination PC.
5353 We ignore the CFA and set a temporary breakpoint at HANDLER.
5354 This is not extremely efficient but it avoids issues in gdb
5355 with computing the DWARF CFA, and it also works even in weird
5356 cases such as throwing an exception from inside a signal
5359 b
= SYMBOL_BLOCK_VALUE (func
);
5360 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
5362 if (!SYMBOL_IS_ARGUMENT (sym
))
5369 insert_exception_resume_breakpoint (ecs
->event_thread
,
5378 stop_stepping (struct execution_control_state
*ecs
)
5381 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_stepping\n");
5383 /* Let callers know we don't want to wait for the inferior anymore. */
5384 ecs
->wait_some_more
= 0;
5387 /* This function handles various cases where we need to continue
5388 waiting for the inferior. */
5389 /* (Used to be the keep_going: label in the old wait_for_inferior). */
5392 keep_going (struct execution_control_state
*ecs
)
5394 /* Make sure normal_stop is called if we get a QUIT handled before
5396 struct cleanup
*old_cleanups
= make_cleanup (resume_cleanups
, 0);
5398 /* Save the pc before execution, to compare with pc after stop. */
5399 ecs
->event_thread
->prev_pc
5400 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5402 /* If we did not do break;, it means we should keep running the
5403 inferior and not return to debugger. */
5405 if (ecs
->event_thread
->control
.trap_expected
5406 && ecs
->event_thread
->suspend
.stop_signal
!= TARGET_SIGNAL_TRAP
)
5408 /* We took a signal (which we are supposed to pass through to
5409 the inferior, else we'd not get here) and we haven't yet
5410 gotten our trap. Simply continue. */
5412 discard_cleanups (old_cleanups
);
5413 resume (currently_stepping (ecs
->event_thread
),
5414 ecs
->event_thread
->suspend
.stop_signal
);
5418 /* Either the trap was not expected, but we are continuing
5419 anyway (the user asked that this signal be passed to the
5422 The signal was SIGTRAP, e.g. it was our signal, but we
5423 decided we should resume from it.
5425 We're going to run this baby now!
5427 Note that insert_breakpoints won't try to re-insert
5428 already inserted breakpoints. Therefore, we don't
5429 care if breakpoints were already inserted, or not. */
5431 if (ecs
->event_thread
->stepping_over_breakpoint
)
5433 struct regcache
*thread_regcache
= get_thread_regcache (ecs
->ptid
);
5435 if (!use_displaced_stepping (get_regcache_arch (thread_regcache
)))
5436 /* Since we can't do a displaced step, we have to remove
5437 the breakpoint while we step it. To keep things
5438 simple, we remove them all. */
5439 remove_breakpoints ();
5443 struct gdb_exception e
;
5445 /* Stop stepping when inserting breakpoints
5447 TRY_CATCH (e
, RETURN_MASK_ERROR
)
5449 insert_breakpoints ();
5453 exception_print (gdb_stderr
, e
);
5454 stop_stepping (ecs
);
5459 ecs
->event_thread
->control
.trap_expected
5460 = ecs
->event_thread
->stepping_over_breakpoint
;
5462 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
5463 specifies that such a signal should be delivered to the
5466 Typically, this would occure when a user is debugging a
5467 target monitor on a simulator: the target monitor sets a
5468 breakpoint; the simulator encounters this break-point and
5469 halts the simulation handing control to GDB; GDB, noteing
5470 that the break-point isn't valid, returns control back to the
5471 simulator; the simulator then delivers the hardware
5472 equivalent of a SIGNAL_TRAP to the program being debugged. */
5474 if (ecs
->event_thread
->suspend
.stop_signal
== TARGET_SIGNAL_TRAP
5475 && !signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
5476 ecs
->event_thread
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
5478 discard_cleanups (old_cleanups
);
5479 resume (currently_stepping (ecs
->event_thread
),
5480 ecs
->event_thread
->suspend
.stop_signal
);
5483 prepare_to_wait (ecs
);
5486 /* This function normally comes after a resume, before
5487 handle_inferior_event exits. It takes care of any last bits of
5488 housekeeping, and sets the all-important wait_some_more flag. */
5491 prepare_to_wait (struct execution_control_state
*ecs
)
5494 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
5496 /* This is the old end of the while loop. Let everybody know we
5497 want to wait for the inferior some more and get called again
5499 ecs
->wait_some_more
= 1;
5502 /* Several print_*_reason functions to print why the inferior has stopped.
5503 We always print something when the inferior exits, or receives a signal.
5504 The rest of the cases are dealt with later on in normal_stop and
5505 print_it_typical. Ideally there should be a call to one of these
5506 print_*_reason functions functions from handle_inferior_event each time
5507 stop_stepping is called. */
5509 /* Print why the inferior has stopped.
5510 We are done with a step/next/si/ni command, print why the inferior has
5511 stopped. For now print nothing. Print a message only if not in the middle
5512 of doing a "step n" operation for n > 1. */
5515 print_end_stepping_range_reason (void)
5517 if ((!inferior_thread ()->step_multi
5518 || !inferior_thread ()->control
.stop_step
)
5519 && ui_out_is_mi_like_p (uiout
))
5520 ui_out_field_string (uiout
, "reason",
5521 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
5524 /* The inferior was terminated by a signal, print why it stopped. */
5527 print_signal_exited_reason (enum target_signal siggnal
)
5529 annotate_signalled ();
5530 if (ui_out_is_mi_like_p (uiout
))
5532 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
5533 ui_out_text (uiout
, "\nProgram terminated with signal ");
5534 annotate_signal_name ();
5535 ui_out_field_string (uiout
, "signal-name",
5536 target_signal_to_name (siggnal
));
5537 annotate_signal_name_end ();
5538 ui_out_text (uiout
, ", ");
5539 annotate_signal_string ();
5540 ui_out_field_string (uiout
, "signal-meaning",
5541 target_signal_to_string (siggnal
));
5542 annotate_signal_string_end ();
5543 ui_out_text (uiout
, ".\n");
5544 ui_out_text (uiout
, "The program no longer exists.\n");
5547 /* The inferior program is finished, print why it stopped. */
5550 print_exited_reason (int exitstatus
)
5552 struct inferior
*inf
= current_inferior ();
5553 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
5555 annotate_exited (exitstatus
);
5558 if (ui_out_is_mi_like_p (uiout
))
5559 ui_out_field_string (uiout
, "reason",
5560 async_reason_lookup (EXEC_ASYNC_EXITED
));
5561 ui_out_text (uiout
, "[Inferior ");
5562 ui_out_text (uiout
, plongest (inf
->num
));
5563 ui_out_text (uiout
, " (");
5564 ui_out_text (uiout
, pidstr
);
5565 ui_out_text (uiout
, ") exited with code ");
5566 ui_out_field_fmt (uiout
, "exit-code", "0%o", (unsigned int) exitstatus
);
5567 ui_out_text (uiout
, "]\n");
5571 if (ui_out_is_mi_like_p (uiout
))
5573 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
5574 ui_out_text (uiout
, "[Inferior ");
5575 ui_out_text (uiout
, plongest (inf
->num
));
5576 ui_out_text (uiout
, " (");
5577 ui_out_text (uiout
, pidstr
);
5578 ui_out_text (uiout
, ") exited normally]\n");
5580 /* Support the --return-child-result option. */
5581 return_child_result_value
= exitstatus
;
5584 /* Signal received, print why the inferior has stopped. The signal table
5585 tells us to print about it. */
5588 print_signal_received_reason (enum target_signal siggnal
)
5592 if (siggnal
== TARGET_SIGNAL_0
&& !ui_out_is_mi_like_p (uiout
))
5594 struct thread_info
*t
= inferior_thread ();
5596 ui_out_text (uiout
, "\n[");
5597 ui_out_field_string (uiout
, "thread-name",
5598 target_pid_to_str (t
->ptid
));
5599 ui_out_field_fmt (uiout
, "thread-id", "] #%d", t
->num
);
5600 ui_out_text (uiout
, " stopped");
5604 ui_out_text (uiout
, "\nProgram received signal ");
5605 annotate_signal_name ();
5606 if (ui_out_is_mi_like_p (uiout
))
5608 (uiout
, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
5609 ui_out_field_string (uiout
, "signal-name",
5610 target_signal_to_name (siggnal
));
5611 annotate_signal_name_end ();
5612 ui_out_text (uiout
, ", ");
5613 annotate_signal_string ();
5614 ui_out_field_string (uiout
, "signal-meaning",
5615 target_signal_to_string (siggnal
));
5616 annotate_signal_string_end ();
5618 ui_out_text (uiout
, ".\n");
5621 /* Reverse execution: target ran out of history info, print why the inferior
5625 print_no_history_reason (void)
5627 ui_out_text (uiout
, "\nNo more reverse-execution history.\n");
5630 /* Here to return control to GDB when the inferior stops for real.
5631 Print appropriate messages, remove breakpoints, give terminal our modes.
5633 STOP_PRINT_FRAME nonzero means print the executing frame
5634 (pc, function, args, file, line number and line text).
5635 BREAKPOINTS_FAILED nonzero means stop was due to error
5636 attempting to insert breakpoints. */
5641 struct target_waitstatus last
;
5643 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
5645 get_last_target_status (&last_ptid
, &last
);
5647 /* If an exception is thrown from this point on, make sure to
5648 propagate GDB's knowledge of the executing state to the
5649 frontend/user running state. A QUIT is an easy exception to see
5650 here, so do this before any filtered output. */
5652 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
5653 else if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5654 && last
.kind
!= TARGET_WAITKIND_EXITED
)
5655 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
5657 /* In non-stop mode, we don't want GDB to switch threads behind the
5658 user's back, to avoid races where the user is typing a command to
5659 apply to thread x, but GDB switches to thread y before the user
5660 finishes entering the command. */
5662 /* As with the notification of thread events, we want to delay
5663 notifying the user that we've switched thread context until
5664 the inferior actually stops.
5666 There's no point in saying anything if the inferior has exited.
5667 Note that SIGNALLED here means "exited with a signal", not
5668 "received a signal". */
5670 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
5671 && target_has_execution
5672 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5673 && last
.kind
!= TARGET_WAITKIND_EXITED
)
5675 target_terminal_ours_for_output ();
5676 printf_filtered (_("[Switching to %s]\n"),
5677 target_pid_to_str (inferior_ptid
));
5678 annotate_thread_changed ();
5679 previous_inferior_ptid
= inferior_ptid
;
5682 if (!breakpoints_always_inserted_mode () && target_has_execution
)
5684 if (remove_breakpoints ())
5686 target_terminal_ours_for_output ();
5687 printf_filtered (_("Cannot remove breakpoints because "
5688 "program is no longer writable.\nFurther "
5689 "execution is probably impossible.\n"));
5693 /* If an auto-display called a function and that got a signal,
5694 delete that auto-display to avoid an infinite recursion. */
5696 if (stopped_by_random_signal
)
5697 disable_current_display ();
5699 /* Don't print a message if in the middle of doing a "step n"
5700 operation for n > 1 */
5701 if (target_has_execution
5702 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
5703 && last
.kind
!= TARGET_WAITKIND_EXITED
5704 && inferior_thread ()->step_multi
5705 && inferior_thread ()->control
.stop_step
)
5708 target_terminal_ours ();
5710 /* Set the current source location. This will also happen if we
5711 display the frame below, but the current SAL will be incorrect
5712 during a user hook-stop function. */
5713 if (has_stack_frames () && !stop_stack_dummy
)
5714 set_current_sal_from_frame (get_current_frame (), 1);
5716 /* Let the user/frontend see the threads as stopped. */
5717 do_cleanups (old_chain
);
5719 /* Look up the hook_stop and run it (CLI internally handles problem
5720 of stop_command's pre-hook not existing). */
5722 catch_errors (hook_stop_stub
, stop_command
,
5723 "Error while running hook_stop:\n", RETURN_MASK_ALL
);
5725 if (!has_stack_frames ())
5728 if (last
.kind
== TARGET_WAITKIND_SIGNALLED
5729 || last
.kind
== TARGET_WAITKIND_EXITED
)
5732 /* Select innermost stack frame - i.e., current frame is frame 0,
5733 and current location is based on that.
5734 Don't do this on return from a stack dummy routine,
5735 or if the program has exited. */
5737 if (!stop_stack_dummy
)
5739 select_frame (get_current_frame ());
5741 /* Print current location without a level number, if
5742 we have changed functions or hit a breakpoint.
5743 Print source line if we have one.
5744 bpstat_print() contains the logic deciding in detail
5745 what to print, based on the event(s) that just occurred. */
5747 /* If --batch-silent is enabled then there's no need to print the current
5748 source location, and to try risks causing an error message about
5749 missing source files. */
5750 if (stop_print_frame
&& !batch_silent
)
5754 int do_frame_printing
= 1;
5755 struct thread_info
*tp
= inferior_thread ();
5757 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
);
5761 /* If we had hit a shared library event breakpoint,
5762 bpstat_print would print out this message. If we hit
5763 an OS-level shared library event, do the same
5765 if (last
.kind
== TARGET_WAITKIND_LOADED
)
5767 printf_filtered (_("Stopped due to shared library event\n"));
5768 source_flag
= SRC_LINE
; /* something bogus */
5769 do_frame_printing
= 0;
5773 /* FIXME: cagney/2002-12-01: Given that a frame ID does
5774 (or should) carry around the function and does (or
5775 should) use that when doing a frame comparison. */
5776 if (tp
->control
.stop_step
5777 && frame_id_eq (tp
->control
.step_frame_id
,
5778 get_frame_id (get_current_frame ()))
5779 && step_start_function
== find_pc_function (stop_pc
))
5780 source_flag
= SRC_LINE
; /* Finished step, just
5781 print source line. */
5783 source_flag
= SRC_AND_LOC
; /* Print location and
5786 case PRINT_SRC_AND_LOC
:
5787 source_flag
= SRC_AND_LOC
; /* Print location and
5790 case PRINT_SRC_ONLY
:
5791 source_flag
= SRC_LINE
;
5794 source_flag
= SRC_LINE
; /* something bogus */
5795 do_frame_printing
= 0;
5798 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
5801 /* The behavior of this routine with respect to the source
5803 SRC_LINE: Print only source line
5804 LOCATION: Print only location
5805 SRC_AND_LOC: Print location and source line. */
5806 if (do_frame_printing
)
5807 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
);
5809 /* Display the auto-display expressions. */
5814 /* Save the function value return registers, if we care.
5815 We might be about to restore their previous contents. */
5816 if (inferior_thread ()->control
.proceed_to_finish
)
5818 /* This should not be necessary. */
5820 regcache_xfree (stop_registers
);
5822 /* NB: The copy goes through to the target picking up the value of
5823 all the registers. */
5824 stop_registers
= regcache_dup (get_current_regcache ());
5827 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
5829 /* Pop the empty frame that contains the stack dummy.
5830 This also restores inferior state prior to the call
5831 (struct infcall_suspend_state). */
5832 struct frame_info
*frame
= get_current_frame ();
5834 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
5836 /* frame_pop() calls reinit_frame_cache as the last thing it
5837 does which means there's currently no selected frame. We
5838 don't need to re-establish a selected frame if the dummy call
5839 returns normally, that will be done by
5840 restore_infcall_control_state. However, we do have to handle
5841 the case where the dummy call is returning after being
5842 stopped (e.g. the dummy call previously hit a breakpoint).
5843 We can't know which case we have so just always re-establish
5844 a selected frame here. */
5845 select_frame (get_current_frame ());
5849 annotate_stopped ();
5851 /* Suppress the stop observer if we're in the middle of:
5853 - a step n (n > 1), as there still more steps to be done.
5855 - a "finish" command, as the observer will be called in
5856 finish_command_continuation, so it can include the inferior
5857 function's return value.
5859 - calling an inferior function, as we pretend we inferior didn't
5860 run at all. The return value of the call is handled by the
5861 expression evaluator, through call_function_by_hand. */
5863 if (!target_has_execution
5864 || last
.kind
== TARGET_WAITKIND_SIGNALLED
5865 || last
.kind
== TARGET_WAITKIND_EXITED
5866 || (!inferior_thread ()->step_multi
5867 && !(inferior_thread ()->control
.stop_bpstat
5868 && inferior_thread ()->control
.proceed_to_finish
)
5869 && !inferior_thread ()->control
.in_infcall
))
5871 if (!ptid_equal (inferior_ptid
, null_ptid
))
5872 observer_notify_normal_stop (inferior_thread ()->control
.stop_bpstat
,
5875 observer_notify_normal_stop (NULL
, stop_print_frame
);
5878 if (target_has_execution
)
5880 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
5881 && last
.kind
!= TARGET_WAITKIND_EXITED
)
5882 /* Delete the breakpoint we stopped at, if it wants to be deleted.
5883 Delete any breakpoint that is to be deleted at the next stop. */
5884 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
5887 /* Try to get rid of automatically added inferiors that are no
5888 longer needed. Keeping those around slows down things linearly.
5889 Note that this never removes the current inferior. */
5894 hook_stop_stub (void *cmd
)
5896 execute_cmd_pre_hook ((struct cmd_list_element
*) cmd
);
5901 signal_stop_state (int signo
)
5903 return signal_stop
[signo
];
5907 signal_print_state (int signo
)
5909 return signal_print
[signo
];
5913 signal_pass_state (int signo
)
5915 return signal_program
[signo
];
5919 signal_cache_update (int signo
)
5923 for (signo
= 0; signo
< (int) TARGET_SIGNAL_LAST
; signo
++)
5924 signal_cache_update (signo
);
5929 signal_pass
[signo
] = (signal_stop
[signo
] == 0
5930 && signal_print
[signo
] == 0
5931 && signal_program
[signo
] == 1);
5935 signal_stop_update (int signo
, int state
)
5937 int ret
= signal_stop
[signo
];
5939 signal_stop
[signo
] = state
;
5940 signal_cache_update (signo
);
5945 signal_print_update (int signo
, int state
)
5947 int ret
= signal_print
[signo
];
5949 signal_print
[signo
] = state
;
5950 signal_cache_update (signo
);
5955 signal_pass_update (int signo
, int state
)
5957 int ret
= signal_program
[signo
];
5959 signal_program
[signo
] = state
;
5960 signal_cache_update (signo
);
5965 sig_print_header (void)
5967 printf_filtered (_("Signal Stop\tPrint\tPass "
5968 "to program\tDescription\n"));
5972 sig_print_info (enum target_signal oursig
)
5974 const char *name
= target_signal_to_name (oursig
);
5975 int name_padding
= 13 - strlen (name
);
5977 if (name_padding
<= 0)
5980 printf_filtered ("%s", name
);
5981 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
5982 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
5983 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
5984 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
5985 printf_filtered ("%s\n", target_signal_to_string (oursig
));
5988 /* Specify how various signals in the inferior should be handled. */
5991 handle_command (char *args
, int from_tty
)
5994 int digits
, wordlen
;
5995 int sigfirst
, signum
, siglast
;
5996 enum target_signal oursig
;
5999 unsigned char *sigs
;
6000 struct cleanup
*old_chain
;
6004 error_no_arg (_("signal to handle"));
6007 /* Allocate and zero an array of flags for which signals to handle. */
6009 nsigs
= (int) TARGET_SIGNAL_LAST
;
6010 sigs
= (unsigned char *) alloca (nsigs
);
6011 memset (sigs
, 0, nsigs
);
6013 /* Break the command line up into args. */
6015 argv
= gdb_buildargv (args
);
6016 old_chain
= make_cleanup_freeargv (argv
);
6018 /* Walk through the args, looking for signal oursigs, signal names, and
6019 actions. Signal numbers and signal names may be interspersed with
6020 actions, with the actions being performed for all signals cumulatively
6021 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
6023 while (*argv
!= NULL
)
6025 wordlen
= strlen (*argv
);
6026 for (digits
= 0; isdigit ((*argv
)[digits
]); digits
++)
6030 sigfirst
= siglast
= -1;
6032 if (wordlen
>= 1 && !strncmp (*argv
, "all", wordlen
))
6034 /* Apply action to all signals except those used by the
6035 debugger. Silently skip those. */
6038 siglast
= nsigs
- 1;
6040 else if (wordlen
>= 1 && !strncmp (*argv
, "stop", wordlen
))
6042 SET_SIGS (nsigs
, sigs
, signal_stop
);
6043 SET_SIGS (nsigs
, sigs
, signal_print
);
6045 else if (wordlen
>= 1 && !strncmp (*argv
, "ignore", wordlen
))
6047 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6049 else if (wordlen
>= 2 && !strncmp (*argv
, "print", wordlen
))
6051 SET_SIGS (nsigs
, sigs
, signal_print
);
6053 else if (wordlen
>= 2 && !strncmp (*argv
, "pass", wordlen
))
6055 SET_SIGS (nsigs
, sigs
, signal_program
);
6057 else if (wordlen
>= 3 && !strncmp (*argv
, "nostop", wordlen
))
6059 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6061 else if (wordlen
>= 3 && !strncmp (*argv
, "noignore", wordlen
))
6063 SET_SIGS (nsigs
, sigs
, signal_program
);
6065 else if (wordlen
>= 4 && !strncmp (*argv
, "noprint", wordlen
))
6067 UNSET_SIGS (nsigs
, sigs
, signal_print
);
6068 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
6070 else if (wordlen
>= 4 && !strncmp (*argv
, "nopass", wordlen
))
6072 UNSET_SIGS (nsigs
, sigs
, signal_program
);
6074 else if (digits
> 0)
6076 /* It is numeric. The numeric signal refers to our own
6077 internal signal numbering from target.h, not to host/target
6078 signal number. This is a feature; users really should be
6079 using symbolic names anyway, and the common ones like
6080 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
6082 sigfirst
= siglast
= (int)
6083 target_signal_from_command (atoi (*argv
));
6084 if ((*argv
)[digits
] == '-')
6087 target_signal_from_command (atoi ((*argv
) + digits
+ 1));
6089 if (sigfirst
> siglast
)
6091 /* Bet he didn't figure we'd think of this case... */
6099 oursig
= target_signal_from_name (*argv
);
6100 if (oursig
!= TARGET_SIGNAL_UNKNOWN
)
6102 sigfirst
= siglast
= (int) oursig
;
6106 /* Not a number and not a recognized flag word => complain. */
6107 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv
);
6111 /* If any signal numbers or symbol names were found, set flags for
6112 which signals to apply actions to. */
6114 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
6116 switch ((enum target_signal
) signum
)
6118 case TARGET_SIGNAL_TRAP
:
6119 case TARGET_SIGNAL_INT
:
6120 if (!allsigs
&& !sigs
[signum
])
6122 if (query (_("%s is used by the debugger.\n\
6123 Are you sure you want to change it? "),
6124 target_signal_to_name ((enum target_signal
) signum
)))
6130 printf_unfiltered (_("Not confirmed, unchanged.\n"));
6131 gdb_flush (gdb_stdout
);
6135 case TARGET_SIGNAL_0
:
6136 case TARGET_SIGNAL_DEFAULT
:
6137 case TARGET_SIGNAL_UNKNOWN
:
6138 /* Make sure that "all" doesn't print these. */
6149 for (signum
= 0; signum
< nsigs
; signum
++)
6152 signal_cache_update (-1);
6153 target_pass_signals ((int) TARGET_SIGNAL_LAST
, signal_pass
);
6157 /* Show the results. */
6158 sig_print_header ();
6159 for (; signum
< nsigs
; signum
++)
6161 sig_print_info (signum
);
6167 do_cleanups (old_chain
);
6171 xdb_handle_command (char *args
, int from_tty
)
6174 struct cleanup
*old_chain
;
6177 error_no_arg (_("xdb command"));
6179 /* Break the command line up into args. */
6181 argv
= gdb_buildargv (args
);
6182 old_chain
= make_cleanup_freeargv (argv
);
6183 if (argv
[1] != (char *) NULL
)
6188 bufLen
= strlen (argv
[0]) + 20;
6189 argBuf
= (char *) xmalloc (bufLen
);
6193 enum target_signal oursig
;
6195 oursig
= target_signal_from_name (argv
[0]);
6196 memset (argBuf
, 0, bufLen
);
6197 if (strcmp (argv
[1], "Q") == 0)
6198 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6201 if (strcmp (argv
[1], "s") == 0)
6203 if (!signal_stop
[oursig
])
6204 sprintf (argBuf
, "%s %s", argv
[0], "stop");
6206 sprintf (argBuf
, "%s %s", argv
[0], "nostop");
6208 else if (strcmp (argv
[1], "i") == 0)
6210 if (!signal_program
[oursig
])
6211 sprintf (argBuf
, "%s %s", argv
[0], "pass");
6213 sprintf (argBuf
, "%s %s", argv
[0], "nopass");
6215 else if (strcmp (argv
[1], "r") == 0)
6217 if (!signal_print
[oursig
])
6218 sprintf (argBuf
, "%s %s", argv
[0], "print");
6220 sprintf (argBuf
, "%s %s", argv
[0], "noprint");
6226 handle_command (argBuf
, from_tty
);
6228 printf_filtered (_("Invalid signal handling flag.\n"));
6233 do_cleanups (old_chain
);
6236 /* Print current contents of the tables set by the handle command.
6237 It is possible we should just be printing signals actually used
6238 by the current target (but for things to work right when switching
6239 targets, all signals should be in the signal tables). */
6242 signals_info (char *signum_exp
, int from_tty
)
6244 enum target_signal oursig
;
6246 sig_print_header ();
6250 /* First see if this is a symbol name. */
6251 oursig
= target_signal_from_name (signum_exp
);
6252 if (oursig
== TARGET_SIGNAL_UNKNOWN
)
6254 /* No, try numeric. */
6256 target_signal_from_command (parse_and_eval_long (signum_exp
));
6258 sig_print_info (oursig
);
6262 printf_filtered ("\n");
6263 /* These ugly casts brought to you by the native VAX compiler. */
6264 for (oursig
= TARGET_SIGNAL_FIRST
;
6265 (int) oursig
< (int) TARGET_SIGNAL_LAST
;
6266 oursig
= (enum target_signal
) ((int) oursig
+ 1))
6270 if (oursig
!= TARGET_SIGNAL_UNKNOWN
6271 && oursig
!= TARGET_SIGNAL_DEFAULT
&& oursig
!= TARGET_SIGNAL_0
)
6272 sig_print_info (oursig
);
6275 printf_filtered (_("\nUse the \"handle\" command "
6276 "to change these tables.\n"));
6279 /* The $_siginfo convenience variable is a bit special. We don't know
6280 for sure the type of the value until we actually have a chance to
6281 fetch the data. The type can change depending on gdbarch, so it is
6282 also dependent on which thread you have selected.
6284 1. making $_siginfo be an internalvar that creates a new value on
6287 2. making the value of $_siginfo be an lval_computed value. */
6289 /* This function implements the lval_computed support for reading a
6293 siginfo_value_read (struct value
*v
)
6295 LONGEST transferred
;
6298 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
6300 value_contents_all_raw (v
),
6302 TYPE_LENGTH (value_type (v
)));
6304 if (transferred
!= TYPE_LENGTH (value_type (v
)))
6305 error (_("Unable to read siginfo"));
6308 /* This function implements the lval_computed support for writing a
6312 siginfo_value_write (struct value
*v
, struct value
*fromval
)
6314 LONGEST transferred
;
6316 transferred
= target_write (¤t_target
,
6317 TARGET_OBJECT_SIGNAL_INFO
,
6319 value_contents_all_raw (fromval
),
6321 TYPE_LENGTH (value_type (fromval
)));
6323 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
6324 error (_("Unable to write siginfo"));
6327 static struct lval_funcs siginfo_value_funcs
=
6333 /* Return a new value with the correct type for the siginfo object of
6334 the current thread using architecture GDBARCH. Return a void value
6335 if there's no object available. */
6337 static struct value
*
6338 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
)
6340 if (target_has_stack
6341 && !ptid_equal (inferior_ptid
, null_ptid
)
6342 && gdbarch_get_siginfo_type_p (gdbarch
))
6344 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6346 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
6349 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
6353 /* infcall_suspend_state contains state about the program itself like its
6354 registers and any signal it received when it last stopped.
6355 This state must be restored regardless of how the inferior function call
6356 ends (either successfully, or after it hits a breakpoint or signal)
6357 if the program is to properly continue where it left off. */
6359 struct infcall_suspend_state
6361 struct thread_suspend_state thread_suspend
;
6362 struct inferior_suspend_state inferior_suspend
;
6366 struct regcache
*registers
;
6368 /* Format of SIGINFO_DATA or NULL if it is not present. */
6369 struct gdbarch
*siginfo_gdbarch
;
6371 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
6372 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
6373 content would be invalid. */
6374 gdb_byte
*siginfo_data
;
6377 struct infcall_suspend_state
*
6378 save_infcall_suspend_state (void)
6380 struct infcall_suspend_state
*inf_state
;
6381 struct thread_info
*tp
= inferior_thread ();
6382 struct inferior
*inf
= current_inferior ();
6383 struct regcache
*regcache
= get_current_regcache ();
6384 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6385 gdb_byte
*siginfo_data
= NULL
;
6387 if (gdbarch_get_siginfo_type_p (gdbarch
))
6389 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6390 size_t len
= TYPE_LENGTH (type
);
6391 struct cleanup
*back_to
;
6393 siginfo_data
= xmalloc (len
);
6394 back_to
= make_cleanup (xfree
, siginfo_data
);
6396 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6397 siginfo_data
, 0, len
) == len
)
6398 discard_cleanups (back_to
);
6401 /* Errors ignored. */
6402 do_cleanups (back_to
);
6403 siginfo_data
= NULL
;
6407 inf_state
= XZALLOC (struct infcall_suspend_state
);
6411 inf_state
->siginfo_gdbarch
= gdbarch
;
6412 inf_state
->siginfo_data
= siginfo_data
;
6415 inf_state
->thread_suspend
= tp
->suspend
;
6416 inf_state
->inferior_suspend
= inf
->suspend
;
6418 /* run_inferior_call will not use the signal due to its `proceed' call with
6419 TARGET_SIGNAL_0 anyway. */
6420 tp
->suspend
.stop_signal
= TARGET_SIGNAL_0
;
6422 inf_state
->stop_pc
= stop_pc
;
6424 inf_state
->registers
= regcache_dup (regcache
);
6429 /* Restore inferior session state to INF_STATE. */
6432 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6434 struct thread_info
*tp
= inferior_thread ();
6435 struct inferior
*inf
= current_inferior ();
6436 struct regcache
*regcache
= get_current_regcache ();
6437 struct gdbarch
*gdbarch
= get_regcache_arch (regcache
);
6439 tp
->suspend
= inf_state
->thread_suspend
;
6440 inf
->suspend
= inf_state
->inferior_suspend
;
6442 stop_pc
= inf_state
->stop_pc
;
6444 if (inf_state
->siginfo_gdbarch
== gdbarch
)
6446 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
6447 size_t len
= TYPE_LENGTH (type
);
6449 /* Errors ignored. */
6450 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
6451 inf_state
->siginfo_data
, 0, len
);
6454 /* The inferior can be gone if the user types "print exit(0)"
6455 (and perhaps other times). */
6456 if (target_has_execution
)
6457 /* NB: The register write goes through to the target. */
6458 regcache_cpy (regcache
, inf_state
->registers
);
6460 discard_infcall_suspend_state (inf_state
);
6464 do_restore_infcall_suspend_state_cleanup (void *state
)
6466 restore_infcall_suspend_state (state
);
6470 make_cleanup_restore_infcall_suspend_state
6471 (struct infcall_suspend_state
*inf_state
)
6473 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
6477 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
6479 regcache_xfree (inf_state
->registers
);
6480 xfree (inf_state
->siginfo_data
);
6485 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
6487 return inf_state
->registers
;
6490 /* infcall_control_state contains state regarding gdb's control of the
6491 inferior itself like stepping control. It also contains session state like
6492 the user's currently selected frame. */
6494 struct infcall_control_state
6496 struct thread_control_state thread_control
;
6497 struct inferior_control_state inferior_control
;
6500 enum stop_stack_kind stop_stack_dummy
;
6501 int stopped_by_random_signal
;
6502 int stop_after_trap
;
6504 /* ID if the selected frame when the inferior function call was made. */
6505 struct frame_id selected_frame_id
;
6508 /* Save all of the information associated with the inferior<==>gdb
6511 struct infcall_control_state
*
6512 save_infcall_control_state (void)
6514 struct infcall_control_state
*inf_status
= xmalloc (sizeof (*inf_status
));
6515 struct thread_info
*tp
= inferior_thread ();
6516 struct inferior
*inf
= current_inferior ();
6518 inf_status
->thread_control
= tp
->control
;
6519 inf_status
->inferior_control
= inf
->control
;
6521 tp
->control
.step_resume_breakpoint
= NULL
;
6522 tp
->control
.exception_resume_breakpoint
= NULL
;
6524 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
6525 chain. If caller's caller is walking the chain, they'll be happier if we
6526 hand them back the original chain when restore_infcall_control_state is
6528 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
6531 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
6532 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
6533 inf_status
->stop_after_trap
= stop_after_trap
;
6535 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
6541 restore_selected_frame (void *args
)
6543 struct frame_id
*fid
= (struct frame_id
*) args
;
6544 struct frame_info
*frame
;
6546 frame
= frame_find_by_id (*fid
);
6548 /* If inf_status->selected_frame_id is NULL, there was no previously
6552 warning (_("Unable to restore previously selected frame."));
6556 select_frame (frame
);
6561 /* Restore inferior session state to INF_STATUS. */
6564 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
6566 struct thread_info
*tp
= inferior_thread ();
6567 struct inferior
*inf
= current_inferior ();
6569 if (tp
->control
.step_resume_breakpoint
)
6570 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
6572 if (tp
->control
.exception_resume_breakpoint
)
6573 tp
->control
.exception_resume_breakpoint
->disposition
6574 = disp_del_at_next_stop
;
6576 /* Handle the bpstat_copy of the chain. */
6577 bpstat_clear (&tp
->control
.stop_bpstat
);
6579 tp
->control
= inf_status
->thread_control
;
6580 inf
->control
= inf_status
->inferior_control
;
6583 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
6584 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
6585 stop_after_trap
= inf_status
->stop_after_trap
;
6587 if (target_has_stack
)
6589 /* The point of catch_errors is that if the stack is clobbered,
6590 walking the stack might encounter a garbage pointer and
6591 error() trying to dereference it. */
6593 (restore_selected_frame
, &inf_status
->selected_frame_id
,
6594 "Unable to restore previously selected frame:\n",
6595 RETURN_MASK_ERROR
) == 0)
6596 /* Error in restoring the selected frame. Select the innermost
6598 select_frame (get_current_frame ());
6605 do_restore_infcall_control_state_cleanup (void *sts
)
6607 restore_infcall_control_state (sts
);
6611 make_cleanup_restore_infcall_control_state
6612 (struct infcall_control_state
*inf_status
)
6614 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
6618 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
6620 if (inf_status
->thread_control
.step_resume_breakpoint
)
6621 inf_status
->thread_control
.step_resume_breakpoint
->disposition
6622 = disp_del_at_next_stop
;
6624 if (inf_status
->thread_control
.exception_resume_breakpoint
)
6625 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
6626 = disp_del_at_next_stop
;
6628 /* See save_infcall_control_state for info on stop_bpstat. */
6629 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
6635 inferior_has_forked (ptid_t pid
, ptid_t
*child_pid
)
6637 struct target_waitstatus last
;
6640 get_last_target_status (&last_ptid
, &last
);
6642 if (last
.kind
!= TARGET_WAITKIND_FORKED
)
6645 if (!ptid_equal (last_ptid
, pid
))
6648 *child_pid
= last
.value
.related_pid
;
6653 inferior_has_vforked (ptid_t pid
, ptid_t
*child_pid
)
6655 struct target_waitstatus last
;
6658 get_last_target_status (&last_ptid
, &last
);
6660 if (last
.kind
!= TARGET_WAITKIND_VFORKED
)
6663 if (!ptid_equal (last_ptid
, pid
))
6666 *child_pid
= last
.value
.related_pid
;
6671 inferior_has_execd (ptid_t pid
, char **execd_pathname
)
6673 struct target_waitstatus last
;
6676 get_last_target_status (&last_ptid
, &last
);
6678 if (last
.kind
!= TARGET_WAITKIND_EXECD
)
6681 if (!ptid_equal (last_ptid
, pid
))
6684 *execd_pathname
= xstrdup (last
.value
.execd_pathname
);
6689 inferior_has_called_syscall (ptid_t pid
, int *syscall_number
)
6691 struct target_waitstatus last
;
6694 get_last_target_status (&last_ptid
, &last
);
6696 if (last
.kind
!= TARGET_WAITKIND_SYSCALL_ENTRY
&&
6697 last
.kind
!= TARGET_WAITKIND_SYSCALL_RETURN
)
6700 if (!ptid_equal (last_ptid
, pid
))
6703 *syscall_number
= last
.value
.syscall_number
;
6707 /* Oft used ptids */
6709 ptid_t minus_one_ptid
;
6711 /* Create a ptid given the necessary PID, LWP, and TID components. */
6714 ptid_build (int pid
, long lwp
, long tid
)
6724 /* Create a ptid from just a pid. */
6727 pid_to_ptid (int pid
)
6729 return ptid_build (pid
, 0, 0);
6732 /* Fetch the pid (process id) component from a ptid. */
6735 ptid_get_pid (ptid_t ptid
)
6740 /* Fetch the lwp (lightweight process) component from a ptid. */
6743 ptid_get_lwp (ptid_t ptid
)
6748 /* Fetch the tid (thread id) component from a ptid. */
6751 ptid_get_tid (ptid_t ptid
)
6756 /* ptid_equal() is used to test equality of two ptids. */
6759 ptid_equal (ptid_t ptid1
, ptid_t ptid2
)
6761 return (ptid1
.pid
== ptid2
.pid
&& ptid1
.lwp
== ptid2
.lwp
6762 && ptid1
.tid
== ptid2
.tid
);
6765 /* Returns true if PTID represents a process. */
6768 ptid_is_pid (ptid_t ptid
)
6770 if (ptid_equal (minus_one_ptid
, ptid
))
6772 if (ptid_equal (null_ptid
, ptid
))
6775 return (ptid_get_lwp (ptid
) == 0 && ptid_get_tid (ptid
) == 0);
6779 ptid_match (ptid_t ptid
, ptid_t filter
)
6781 if (ptid_equal (filter
, minus_one_ptid
))
6783 if (ptid_is_pid (filter
)
6784 && ptid_get_pid (ptid
) == ptid_get_pid (filter
))
6786 else if (ptid_equal (ptid
, filter
))
6792 /* restore_inferior_ptid() will be used by the cleanup machinery
6793 to restore the inferior_ptid value saved in a call to
6794 save_inferior_ptid(). */
6797 restore_inferior_ptid (void *arg
)
6799 ptid_t
*saved_ptid_ptr
= arg
;
6801 inferior_ptid
= *saved_ptid_ptr
;
6805 /* Save the value of inferior_ptid so that it may be restored by a
6806 later call to do_cleanups(). Returns the struct cleanup pointer
6807 needed for later doing the cleanup. */
6810 save_inferior_ptid (void)
6812 ptid_t
*saved_ptid_ptr
;
6814 saved_ptid_ptr
= xmalloc (sizeof (ptid_t
));
6815 *saved_ptid_ptr
= inferior_ptid
;
6816 return make_cleanup (restore_inferior_ptid
, saved_ptid_ptr
);
6820 /* User interface for reverse debugging:
6821 Set exec-direction / show exec-direction commands
6822 (returns error unless target implements to_set_exec_direction method). */
6824 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
6825 static const char exec_forward
[] = "forward";
6826 static const char exec_reverse
[] = "reverse";
6827 static const char *exec_direction
= exec_forward
;
6828 static const char *exec_direction_names
[] = {
6835 set_exec_direction_func (char *args
, int from_tty
,
6836 struct cmd_list_element
*cmd
)
6838 if (target_can_execute_reverse
)
6840 if (!strcmp (exec_direction
, exec_forward
))
6841 execution_direction
= EXEC_FORWARD
;
6842 else if (!strcmp (exec_direction
, exec_reverse
))
6843 execution_direction
= EXEC_REVERSE
;
6847 exec_direction
= exec_forward
;
6848 error (_("Target does not support this operation."));
6853 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
6854 struct cmd_list_element
*cmd
, const char *value
)
6856 switch (execution_direction
) {
6858 fprintf_filtered (out
, _("Forward.\n"));
6861 fprintf_filtered (out
, _("Reverse.\n"));
6865 fprintf_filtered (out
, _("Forward (target `%s' does not "
6866 "support exec-direction).\n"),
6872 /* User interface for non-stop mode. */
6877 set_non_stop (char *args
, int from_tty
,
6878 struct cmd_list_element
*c
)
6880 if (target_has_execution
)
6882 non_stop_1
= non_stop
;
6883 error (_("Cannot change this setting while the inferior is running."));
6886 non_stop
= non_stop_1
;
6890 show_non_stop (struct ui_file
*file
, int from_tty
,
6891 struct cmd_list_element
*c
, const char *value
)
6893 fprintf_filtered (file
,
6894 _("Controlling the inferior in non-stop mode is %s.\n"),
6899 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
6900 struct cmd_list_element
*c
, const char *value
)
6902 fprintf_filtered (file
, _("Resuming the execution of threads "
6903 "of all processes is %s.\n"), value
);
6907 _initialize_infrun (void)
6912 add_info ("signals", signals_info
, _("\
6913 What debugger does when program gets various signals.\n\
6914 Specify a signal as argument to print info on that signal only."));
6915 add_info_alias ("handle", "signals", 0);
6917 add_com ("handle", class_run
, handle_command
, _("\
6918 Specify how to handle a signal.\n\
6919 Args are signals and actions to apply to those signals.\n\
6920 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
6921 from 1-15 are allowed for compatibility with old versions of GDB.\n\
6922 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
6923 The special arg \"all\" is recognized to mean all signals except those\n\
6924 used by the debugger, typically SIGTRAP and SIGINT.\n\
6925 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
6926 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
6927 Stop means reenter debugger if this signal happens (implies print).\n\
6928 Print means print a message if this signal happens.\n\
6929 Pass means let program see this signal; otherwise program doesn't know.\n\
6930 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
6931 Pass and Stop may be combined."));
6934 add_com ("lz", class_info
, signals_info
, _("\
6935 What debugger does when program gets various signals.\n\
6936 Specify a signal as argument to print info on that signal only."));
6937 add_com ("z", class_run
, xdb_handle_command
, _("\
6938 Specify how to handle a signal.\n\
6939 Args are signals and actions to apply to those signals.\n\
6940 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
6941 from 1-15 are allowed for compatibility with old versions of GDB.\n\
6942 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
6943 The special arg \"all\" is recognized to mean all signals except those\n\
6944 used by the debugger, typically SIGTRAP and SIGINT.\n\
6945 Recognized actions include \"s\" (toggles between stop and nostop),\n\
6946 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
6947 nopass), \"Q\" (noprint)\n\
6948 Stop means reenter debugger if this signal happens (implies print).\n\
6949 Print means print a message if this signal happens.\n\
6950 Pass means let program see this signal; otherwise program doesn't know.\n\
6951 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
6952 Pass and Stop may be combined."));
6956 stop_command
= add_cmd ("stop", class_obscure
,
6957 not_just_help_class_command
, _("\
6958 There is no `stop' command, but you can set a hook on `stop'.\n\
6959 This allows you to set a list of commands to be run each time execution\n\
6960 of the program stops."), &cmdlist
);
6962 add_setshow_zinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
6963 Set inferior debugging."), _("\
6964 Show inferior debugging."), _("\
6965 When non-zero, inferior specific debugging is enabled."),
6968 &setdebuglist
, &showdebuglist
);
6970 add_setshow_boolean_cmd ("displaced", class_maintenance
,
6971 &debug_displaced
, _("\
6972 Set displaced stepping debugging."), _("\
6973 Show displaced stepping debugging."), _("\
6974 When non-zero, displaced stepping specific debugging is enabled."),
6976 show_debug_displaced
,
6977 &setdebuglist
, &showdebuglist
);
6979 add_setshow_boolean_cmd ("non-stop", no_class
,
6981 Set whether gdb controls the inferior in non-stop mode."), _("\
6982 Show whether gdb controls the inferior in non-stop mode."), _("\
6983 When debugging a multi-threaded program and this setting is\n\
6984 off (the default, also called all-stop mode), when one thread stops\n\
6985 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
6986 all other threads in the program while you interact with the thread of\n\
6987 interest. When you continue or step a thread, you can allow the other\n\
6988 threads to run, or have them remain stopped, but while you inspect any\n\
6989 thread's state, all threads stop.\n\
6991 In non-stop mode, when one thread stops, other threads can continue\n\
6992 to run freely. You'll be able to step each thread independently,\n\
6993 leave it stopped or free to run as needed."),
6999 numsigs
= (int) TARGET_SIGNAL_LAST
;
7000 signal_stop
= (unsigned char *) xmalloc (sizeof (signal_stop
[0]) * numsigs
);
7001 signal_print
= (unsigned char *)
7002 xmalloc (sizeof (signal_print
[0]) * numsigs
);
7003 signal_program
= (unsigned char *)
7004 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7005 signal_pass
= (unsigned char *)
7006 xmalloc (sizeof (signal_program
[0]) * numsigs
);
7007 for (i
= 0; i
< numsigs
; i
++)
7010 signal_print
[i
] = 1;
7011 signal_program
[i
] = 1;
7014 /* Signals caused by debugger's own actions
7015 should not be given to the program afterwards. */
7016 signal_program
[TARGET_SIGNAL_TRAP
] = 0;
7017 signal_program
[TARGET_SIGNAL_INT
] = 0;
7019 /* Signals that are not errors should not normally enter the debugger. */
7020 signal_stop
[TARGET_SIGNAL_ALRM
] = 0;
7021 signal_print
[TARGET_SIGNAL_ALRM
] = 0;
7022 signal_stop
[TARGET_SIGNAL_VTALRM
] = 0;
7023 signal_print
[TARGET_SIGNAL_VTALRM
] = 0;
7024 signal_stop
[TARGET_SIGNAL_PROF
] = 0;
7025 signal_print
[TARGET_SIGNAL_PROF
] = 0;
7026 signal_stop
[TARGET_SIGNAL_CHLD
] = 0;
7027 signal_print
[TARGET_SIGNAL_CHLD
] = 0;
7028 signal_stop
[TARGET_SIGNAL_IO
] = 0;
7029 signal_print
[TARGET_SIGNAL_IO
] = 0;
7030 signal_stop
[TARGET_SIGNAL_POLL
] = 0;
7031 signal_print
[TARGET_SIGNAL_POLL
] = 0;
7032 signal_stop
[TARGET_SIGNAL_URG
] = 0;
7033 signal_print
[TARGET_SIGNAL_URG
] = 0;
7034 signal_stop
[TARGET_SIGNAL_WINCH
] = 0;
7035 signal_print
[TARGET_SIGNAL_WINCH
] = 0;
7036 signal_stop
[TARGET_SIGNAL_PRIO
] = 0;
7037 signal_print
[TARGET_SIGNAL_PRIO
] = 0;
7039 /* These signals are used internally by user-level thread
7040 implementations. (See signal(5) on Solaris.) Like the above
7041 signals, a healthy program receives and handles them as part of
7042 its normal operation. */
7043 signal_stop
[TARGET_SIGNAL_LWP
] = 0;
7044 signal_print
[TARGET_SIGNAL_LWP
] = 0;
7045 signal_stop
[TARGET_SIGNAL_WAITING
] = 0;
7046 signal_print
[TARGET_SIGNAL_WAITING
] = 0;
7047 signal_stop
[TARGET_SIGNAL_CANCEL
] = 0;
7048 signal_print
[TARGET_SIGNAL_CANCEL
] = 0;
7050 /* Update cached state. */
7051 signal_cache_update (-1);
7053 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
7054 &stop_on_solib_events
, _("\
7055 Set stopping for shared library events."), _("\
7056 Show stopping for shared library events."), _("\
7057 If nonzero, gdb will give control to the user when the dynamic linker\n\
7058 notifies gdb of shared library events. The most common event of interest\n\
7059 to the user would be loading/unloading of a new library."),
7061 show_stop_on_solib_events
,
7062 &setlist
, &showlist
);
7064 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
7065 follow_fork_mode_kind_names
,
7066 &follow_fork_mode_string
, _("\
7067 Set debugger response to a program call of fork or vfork."), _("\
7068 Show debugger response to a program call of fork or vfork."), _("\
7069 A fork or vfork creates a new process. follow-fork-mode can be:\n\
7070 parent - the original process is debugged after a fork\n\
7071 child - the new process is debugged after a fork\n\
7072 The unfollowed process will continue to run.\n\
7073 By default, the debugger will follow the parent process."),
7075 show_follow_fork_mode_string
,
7076 &setlist
, &showlist
);
7078 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
7079 follow_exec_mode_names
,
7080 &follow_exec_mode_string
, _("\
7081 Set debugger response to a program call of exec."), _("\
7082 Show debugger response to a program call of exec."), _("\
7083 An exec call replaces the program image of a process.\n\
7085 follow-exec-mode can be:\n\
7087 new - the debugger creates a new inferior and rebinds the process\n\
7088 to this new inferior. The program the process was running before\n\
7089 the exec call can be restarted afterwards by restarting the original\n\
7092 same - the debugger keeps the process bound to the same inferior.\n\
7093 The new executable image replaces the previous executable loaded in\n\
7094 the inferior. Restarting the inferior after the exec call restarts\n\
7095 the executable the process was running after the exec call.\n\
7097 By default, the debugger will use the same inferior."),
7099 show_follow_exec_mode_string
,
7100 &setlist
, &showlist
);
7102 add_setshow_enum_cmd ("scheduler-locking", class_run
,
7103 scheduler_enums
, &scheduler_mode
, _("\
7104 Set mode for locking scheduler during execution."), _("\
7105 Show mode for locking scheduler during execution."), _("\
7106 off == no locking (threads may preempt at any time)\n\
7107 on == full locking (no thread except the current thread may run)\n\
7108 step == scheduler locked during every single-step operation.\n\
7109 In this mode, no other thread may run during a step command.\n\
7110 Other threads may run while stepping over a function call ('next')."),
7111 set_schedlock_func
, /* traps on target vector */
7112 show_scheduler_mode
,
7113 &setlist
, &showlist
);
7115 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
7116 Set mode for resuming threads of all processes."), _("\
7117 Show mode for resuming threads of all processes."), _("\
7118 When on, execution commands (such as 'continue' or 'next') resume all\n\
7119 threads of all processes. When off (which is the default), execution\n\
7120 commands only resume the threads of the current process. The set of\n\
7121 threads that are resumed is further refined by the scheduler-locking\n\
7122 mode (see help set scheduler-locking)."),
7124 show_schedule_multiple
,
7125 &setlist
, &showlist
);
7127 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
7128 Set mode of the step operation."), _("\
7129 Show mode of the step operation."), _("\
7130 When set, doing a step over a function without debug line information\n\
7131 will stop at the first instruction of that function. Otherwise, the\n\
7132 function is skipped and the step command stops at a different source line."),
7134 show_step_stop_if_no_debug
,
7135 &setlist
, &showlist
);
7137 add_setshow_enum_cmd ("displaced-stepping", class_run
,
7138 can_use_displaced_stepping_enum
,
7139 &can_use_displaced_stepping
, _("\
7140 Set debugger's willingness to use displaced stepping."), _("\
7141 Show debugger's willingness to use displaced stepping."), _("\
7142 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
7143 supported by the target architecture. If off, gdb will not use displaced\n\
7144 stepping to step over breakpoints, even if such is supported by the target\n\
7145 architecture. If auto (which is the default), gdb will use displaced stepping\n\
7146 if the target architecture supports it and non-stop mode is active, but will not\n\
7147 use it in all-stop mode (see help set non-stop)."),
7149 show_can_use_displaced_stepping
,
7150 &setlist
, &showlist
);
7152 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
7153 &exec_direction
, _("Set direction of execution.\n\
7154 Options are 'forward' or 'reverse'."),
7155 _("Show direction of execution (forward/reverse)."),
7156 _("Tells gdb whether to execute forward or backward."),
7157 set_exec_direction_func
, show_exec_direction_func
,
7158 &setlist
, &showlist
);
7160 /* Set/show detach-on-fork: user-settable mode. */
7162 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
7163 Set whether gdb will detach the child of a fork."), _("\
7164 Show whether gdb will detach the child of a fork."), _("\
7165 Tells gdb whether to detach the child of a fork."),
7166 NULL
, NULL
, &setlist
, &showlist
);
7168 /* ptid initializations */
7169 null_ptid
= ptid_build (0, 0, 0);
7170 minus_one_ptid
= ptid_build (-1, 0, 0);
7171 inferior_ptid
= null_ptid
;
7172 target_last_wait_ptid
= minus_one_ptid
;
7174 observer_attach_thread_ptid_changed (infrun_thread_ptid_changed
);
7175 observer_attach_thread_stop_requested (infrun_thread_stop_requested
);
7176 observer_attach_thread_exit (infrun_thread_thread_exit
);
7177 observer_attach_inferior_exit (infrun_inferior_exit
);
7179 /* Explicitly create without lookup, since that tries to create a
7180 value with a void typed value, and when we get here, gdbarch
7181 isn't initialized yet. At this point, we're quite sure there
7182 isn't another convenience variable of the same name. */
7183 create_internalvar_type_lazy ("_siginfo", siginfo_make_value
);
7185 add_setshow_boolean_cmd ("observer", no_class
,
7186 &observer_mode_1
, _("\
7187 Set whether gdb controls the inferior in observer mode."), _("\
7188 Show whether gdb controls the inferior in observer mode."), _("\
7189 In observer mode, GDB can get data from the inferior, but not\n\
7190 affect its execution. Registers and memory may not be changed,\n\
7191 breakpoints may not be set, and the program cannot be interrupted\n\