static int currently_stepping (struct thread_info *tp);
-static int currently_stepping_callback (struct thread_info *tp, void *data);
+static int currently_stepping_or_nexting_callback (struct thread_info *tp,
+ void *data);
static void xdb_handle_command (char *args, int from_tty);
void _initialize_infrun (void);
+void nullify_last_target_wait_ptid (void);
+
/* When set, stop the 'step' command if we enter a function which has
no line number information. The normal behavior is that we step
over such function. */
void init_infwait_state (void);
-/* This is used to remember when a fork or vfork event was caught by a
- catchpoint, and thus the event is to be followed at the next resume
- of the inferior, and not immediately. */
-static struct
-{
- enum target_waitkind kind;
- struct
- {
- ptid_t parent_pid;
- ptid_t child_pid;
- }
- fork_event;
-}
-pending_follow;
-
static const char follow_fork_mode_child[] = "child";
static const char follow_fork_mode_parent[] = "parent";
}
\f
+/* Tell the target to follow the fork we're stopped at. Returns true
+ if the inferior should be resumed; false, if the target for some
+ reason decided it's best not to resume. */
+
static int
follow_fork (void)
{
int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
+ int should_resume = 1;
+ struct thread_info *tp;
+
+ /* Copy user stepping state to the new inferior thread. FIXME: the
+ followed fork child thread should have a copy of most of the
+ parent thread structure's run control related fields, not just these.
+ Initialized to avoid "may be used uninitialized" warnings from gcc. */
+ struct breakpoint *step_resume_breakpoint = NULL;
+ CORE_ADDR step_range_start = 0;
+ CORE_ADDR step_range_end = 0;
+ struct frame_id step_frame_id = { 0 };
+
+ if (!non_stop)
+ {
+ ptid_t wait_ptid;
+ struct target_waitstatus wait_status;
+
+ /* Get the last target status returned by target_wait(). */
+ get_last_target_status (&wait_ptid, &wait_status);
- return target_follow_fork (follow_child);
+ /* If not stopped at a fork event, then there's nothing else to
+ do. */
+ if (wait_status.kind != TARGET_WAITKIND_FORKED
+ && wait_status.kind != TARGET_WAITKIND_VFORKED)
+ return 1;
+
+ /* Check if we switched over from WAIT_PTID, since the event was
+ reported. */
+ if (!ptid_equal (wait_ptid, minus_one_ptid)
+ && !ptid_equal (inferior_ptid, wait_ptid))
+ {
+ /* We did. Switch back to WAIT_PTID thread, to tell the
+ target to follow it (in either direction). We'll
+ afterwards refuse to resume, and inform the user what
+ happened. */
+ switch_to_thread (wait_ptid);
+ should_resume = 0;
+ }
+ }
+
+ tp = inferior_thread ();
+
+ /* If there were any forks/vforks that were caught and are now to be
+ followed, then do so now. */
+ switch (tp->pending_follow.kind)
+ {
+ case TARGET_WAITKIND_FORKED:
+ case TARGET_WAITKIND_VFORKED:
+ {
+ ptid_t parent, child;
+
+ /* If the user did a next/step, etc, over a fork call,
+ preserve the stepping state in the fork child. */
+ if (follow_child && should_resume)
+ {
+ step_resume_breakpoint
+ = clone_momentary_breakpoint (tp->step_resume_breakpoint);
+ step_range_start = tp->step_range_start;
+ step_range_end = tp->step_range_end;
+ step_frame_id = tp->step_frame_id;
+
+ /* For now, delete the parent's sr breakpoint, otherwise,
+ parent/child sr breakpoints are considered duplicates,
+ and the child version will not be installed. Remove
+ this when the breakpoints module becomes aware of
+ inferiors and address spaces. */
+ delete_step_resume_breakpoint (tp);
+ tp->step_range_start = 0;
+ tp->step_range_end = 0;
+ tp->step_frame_id = null_frame_id;
+ }
+
+ parent = inferior_ptid;
+ child = tp->pending_follow.value.related_pid;
+
+ /* Tell the target to do whatever is necessary to follow
+ either parent or child. */
+ if (target_follow_fork (follow_child))
+ {
+ /* Target refused to follow, or there's some other reason
+ we shouldn't resume. */
+ should_resume = 0;
+ }
+ else
+ {
+ /* This pending follow fork event is now handled, one way
+ or another. The previous selected thread may be gone
+ from the lists by now, but if it is still around, need
+ to clear the pending follow request. */
+ tp = find_thread_ptid (parent);
+ if (tp)
+ tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+
+ /* This makes sure we don't try to apply the "Switched
+ over from WAIT_PID" logic above. */
+ nullify_last_target_wait_ptid ();
+
+ /* If we followed the child, switch to it... */
+ if (follow_child)
+ {
+ switch_to_thread (child);
+
+ /* ... and preserve the stepping state, in case the
+ user was stepping over the fork call. */
+ if (should_resume)
+ {
+ tp = inferior_thread ();
+ tp->step_resume_breakpoint = step_resume_breakpoint;
+ tp->step_range_start = step_range_start;
+ tp->step_range_end = step_range_end;
+ tp->step_frame_id = step_frame_id;
+ }
+ else
+ {
+ /* If we get here, it was because we're trying to
+ resume from a fork catchpoint, but, the user
+ has switched threads away from the thread that
+ forked. In that case, the resume command
+ issued is most likely not applicable to the
+ child, so just warn, and refuse to resume. */
+ warning (_("\
+Not resuming: switched threads before following fork child.\n"));
+ }
+
+ /* Reset breakpoints in the child as appropriate. */
+ follow_inferior_reset_breakpoints ();
+ }
+ else
+ switch_to_thread (parent);
+ }
+ }
+ break;
+ case TARGET_WAITKIND_SPURIOUS:
+ /* Nothing to follow. */
+ break;
+ default:
+ internal_error (__FILE__, __LINE__,
+ "Unexpected pending_follow.kind %d\n",
+ tp->pending_follow.kind);
+ break;
+ }
+
+ return should_resume;
}
void
th->step_range_start = 0;
th->step_range_end = 0;
+ /* The target reports the exec event to the main thread, even if
+ some other thread does the exec, and even if the main thread was
+ already stopped --- if debugging in non-stop mode, it's possible
+ the user had the main thread held stopped in the previous image
+ --- release it now. This is the same behavior as step-over-exec
+ with scheduler-locking on in all-stop mode. */
+ th->stop_requested = 0;
+
/* What is this a.out's name? */
printf_unfiltered (_("Executing new program: %s\n"), execd_pathname);
{
int should_resume = 1;
struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
-
- /* Note that these must be reset if we follow a fork below. */
struct regcache *regcache = get_current_regcache ();
struct gdbarch *gdbarch = get_regcache_arch (regcache);
struct thread_info *tp = inferior_thread ();
if (step)
step = maybe_software_singlestep (gdbarch, pc);
- /* If there were any forks/vforks/execs that were caught and are
- now to be followed, then do so. */
- switch (pending_follow.kind)
- {
- case TARGET_WAITKIND_FORKED:
- case TARGET_WAITKIND_VFORKED:
- pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
- if (follow_fork ())
- should_resume = 0;
-
- /* Following a child fork will change our notion of current
- thread. */
- tp = inferior_thread ();
- regcache = get_current_regcache ();
- gdbarch = get_regcache_arch (regcache);
- pc = regcache_read_pc (regcache);
- break;
-
- default:
- break;
- }
-
- /* Install inferior's terminal modes. */
- target_terminal_inferior ();
-
if (should_resume)
{
ptid_t resume_ptid;
displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
}
+ /* Install inferior's terminal modes. */
+ target_terminal_inferior ();
+
/* Avoid confusing the next resume, if the next stop/resume
happens to apply to another thread. */
tp->stop_signal = TARGET_SIGNAL_0;
}
}
-/* This should be suitable for any targets that support threads. */
+/* Check the current thread against the thread that reported the most recent
+ event. If a step-over is required return TRUE and set the current thread
+ to the old thread. Otherwise return FALSE.
+
+ This should be suitable for any targets that support threads. */
static int
prepare_to_proceed (int step)
{
ptid_t wait_ptid;
struct target_waitstatus wait_status;
+ int schedlock_enabled;
+
+ /* With non-stop mode on, threads are always handled individually. */
+ gdb_assert (! non_stop);
/* Get the last target status returned by target_wait(). */
get_last_target_status (&wait_ptid, &wait_status);
return 0;
}
+ schedlock_enabled = (scheduler_mode == schedlock_on
+ || (scheduler_mode == schedlock_step
+ && step));
+
/* Switched over from WAIT_PID. */
if (!ptid_equal (wait_ptid, minus_one_ptid)
- && !ptid_equal (inferior_ptid, wait_ptid))
+ && !ptid_equal (inferior_ptid, wait_ptid)
+ /* Don't single step WAIT_PID if scheduler locking is on. */
+ && !schedlock_enabled)
{
struct regcache *regcache = get_thread_regcache (wait_ptid);
void
proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
{
- struct regcache *regcache = get_current_regcache ();
- struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ struct regcache *regcache;
+ struct gdbarch *gdbarch;
struct thread_info *tp;
- CORE_ADDR pc = regcache_read_pc (regcache);
+ CORE_ADDR pc;
int oneproc = 0;
+ /* If we're stopped at a fork/vfork, follow the branch set by the
+ "set follow-fork-mode" command; otherwise, we'll just proceed
+ resuming the current thread. */
+ if (!follow_fork ())
+ {
+ /* The target for some reason decided not to resume. */
+ normal_stop ();
+ return;
+ }
+
+ regcache = get_current_regcache ();
+ gdbarch = get_regcache_arch (regcache);
+ pc = regcache_read_pc (regcache);
+
if (step > 0)
step_start_function = find_pc_function (pc);
if (step < 0)
&& !ptid_equal (last_ptid, null_ptid)
&& !ptid_equal (last_ptid, minus_one_ptid))
{
- last_thread = find_thread_pid (last_ptid);
+ last_thread = find_thread_ptid (last_ptid);
if (last_thread)
{
tp->stop_signal = last_thread->stop_signal;
breakpoint_init_inferior (inf_starting);
- /* The first resume is not following a fork/vfork/exec. */
- pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
-
clear_proceed_status ();
stepping_past_singlestep_breakpoint = 0;
have consistent output as if the stop event had been
reported. */
ecs->ptid = info->ptid;
- ecs->event_thread = find_thread_pid (info->ptid);
+ ecs->event_thread = find_thread_ptid (info->ptid);
ecs->ws.kind = TARGET_WAITKIND_STOPPED;
ecs->ws.value.sig = TARGET_SIGNAL_0;
iterate_over_threads (infrun_thread_stop_requested_callback, &ptid);
}
-void nullify_last_target_wait_ptid (void);
-
static void
infrun_thread_thread_exit (struct thread_info *tp, int silent)
{
struct cleanup *old_chain;
if (deprecated_target_wait_hook)
- ecs->ptid = deprecated_target_wait_hook (waiton_ptid, &ecs->ws);
+ ecs->ptid = deprecated_target_wait_hook (waiton_ptid, &ecs->ws, 0);
else
- ecs->ptid = target_wait (waiton_ptid, &ecs->ws);
+ ecs->ptid = target_wait (waiton_ptid, &ecs->ws, 0);
if (debug_infrun)
print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
if (deprecated_target_wait_hook)
ecs->ptid =
- deprecated_target_wait_hook (waiton_ptid, &ecs->ws);
+ deprecated_target_wait_hook (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
else
- ecs->ptid = target_wait (waiton_ptid, &ecs->ws);
+ ecs->ptid = target_wait (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
if (debug_infrun)
print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
&& ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
add_thread (ecs->ptid);
- ecs->event_thread = find_thread_pid (ecs->ptid);
+ ecs->event_thread = find_thread_ptid (ecs->ptid);
/* Dependent on valid ECS->EVENT_THREAD. */
adjust_pc_after_break (ecs);
/* Record the exit code in the convenience variable $_exitcode, so
that the user can inspect this again later. */
- set_internalvar (lookup_internalvar ("_exitcode"),
- value_from_longest (builtin_type_int32,
- (LONGEST) ecs->ws.value.integer));
+ set_internalvar_integer (lookup_internalvar ("_exitcode"),
+ (LONGEST) ecs->ws.value.integer);
gdb_flush (gdb_stdout);
target_mourn_inferior ();
singlestep_breakpoints_inserted_p = 0;
case TARGET_WAITKIND_VFORKED:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
- pending_follow.kind = ecs->ws.kind;
-
- pending_follow.fork_event.parent_pid = ecs->ptid;
- pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
if (!ptid_equal (ecs->ptid, inferior_ptid))
{
detach_breakpoints (child_pid);
}
+ /* In case the event is caught by a catchpoint, remember that
+ the event is to be followed at the next resume of the thread,
+ and not immediately. */
+ ecs->event_thread->pending_follow = ecs->ws;
+
stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
/* If no catchpoint triggered for this, then keep going. */
if (ecs->random_signal)
{
+ int should_resume;
+
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
- keep_going (ecs);
+
+ should_resume = follow_fork ();
+
+ ecs->event_thread = inferior_thread ();
+ ecs->ptid = inferior_ptid;
+
+ if (should_resume)
+ keep_going (ecs);
+ else
+ stop_stepping (ecs);
return;
}
ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
stop_signal = ecs->event_thread->stop_signal;
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
ecs->ptid = singlestep_ptid;
- ecs->event_thread = find_thread_pid (ecs->ptid);
+ ecs->event_thread = find_thread_ptid (ecs->ptid);
ecs->event_thread->stop_signal = stop_signal;
stop_pc = new_singlestep_pc;
}
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: thread_hop_needed\n");
+ /* Switch context before touching inferior memory, the
+ previous thread may have exited. */
+ if (!ptid_equal (inferior_ptid, ecs->ptid))
+ context_switch (ecs->ptid);
+
/* Saw a breakpoint, but it was hit by the wrong thread.
Just continue. */
error (_("Cannot step over breakpoint hit in wrong thread"));
else
{ /* Single step */
- if (!ptid_equal (inferior_ptid, ecs->ptid))
- context_switch (ecs->ptid);
-
if (!non_stop)
{
/* Only need to require the next event from this
if (!non_stop)
{
struct thread_info *tp;
- tp = iterate_over_threads (currently_stepping_callback,
+ tp = iterate_over_threads (currently_stepping_or_nexting_callback,
ecs->event_thread);
if (tp)
{
return;
}
+ /* If the stepping thread exited, then don't try reverting
+ back to it, just keep going. We need to query the target
+ in case it doesn't support thread exit events. */
+ if (is_exited (tp->ptid)
+ || !target_thread_alive (tp->ptid))
+ {
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog, "\
+infrun: not switching back to stepped thread, it has vanished\n");
+
+ delete_thread (tp->ptid);
+ keep_going (ecs);
+ return;
+ }
+
/* Otherwise, we no longer expect a trap in the current thread.
Clear the trap_expected flag before switching back -- this is
what keep_going would do as well, if we called it. */
keep_going (ecs);
}
-/* Are we in the middle of stepping? */
+/* Is thread TP in the middle of single-stepping? */
static int
-currently_stepping_thread (struct thread_info *tp)
+currently_stepping (struct thread_info *tp)
{
- return (tp->step_range_end && tp->step_resume_breakpoint == NULL)
- || tp->trap_expected
- || tp->stepping_through_solib_after_catch;
+ return ((tp->step_range_end && tp->step_resume_breakpoint == NULL)
+ || tp->trap_expected
+ || tp->stepping_through_solib_after_catch
+ || bpstat_should_step ());
}
-static int
-currently_stepping_callback (struct thread_info *tp, void *data)
-{
- /* Return true if any thread *but* the one passed in "data" is
- in the middle of stepping. */
- return tp != data && currently_stepping_thread (tp);
-}
+/* Returns true if any thread *but* the one passed in "data" is in the
+ middle of stepping or of handling a "next". */
static int
-currently_stepping (struct thread_info *tp)
+currently_stepping_or_nexting_callback (struct thread_info *tp, void *data)
{
- return currently_stepping_thread (tp) || bpstat_should_step ();
+ if (tp == data)
+ return 0;
+
+ return (tp->step_range_end
+ || tp->trap_expected
+ || tp->stepping_through_solib_after_catch);
}
/* Inferior has stepped into a subroutine call with source code that
projects / deliverable / binutils-gdb.git / blobdiff