/*
This file is part of LilyPond, the GNU music typesetter.
- Copyright (C) 2005--2011 Erik Sandberg <mandolaerik@gmail.com>
+ Copyright (C) 2005--2015 Erik Sandberg <mandolaerik@gmail.com>
LilyPond is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include "dispatcher.hh"
#include "input.hh"
#include "international.hh"
-#include "ly-smobs.icc"
#include "warn.hh"
+#include "lily-imports.hh"
-IMPLEMENT_SMOBS (Dispatcher);
-IMPLEMENT_TYPE_P (Dispatcher, "ly:dispatcher?");
-IMPLEMENT_DEFAULT_EQUAL_P (Dispatcher);
+const char * const Dispatcher::type_p_name_ = "ly:dispatcher?";
Dispatcher::~Dispatcher ()
{
Dispatcher::Dispatcher ()
{
- self_scm_ = SCM_EOL;
listeners_ = SCM_EOL;
dispatchers_ = SCM_EOL;
listen_classes_ = SCM_EOL;
}
SCM
-Dispatcher::mark_smob (SCM sm)
+Dispatcher::mark_smob () const
{
- Dispatcher *me = (Dispatcher *) SCM_CELL_WORD_1 (sm);
- scm_gc_mark (me->dispatchers_);
- scm_gc_mark (me->listen_classes_);
- return me->listeners_;
+ scm_gc_mark (dispatchers_);
+ scm_gc_mark (listen_classes_);
+ return listeners_;
}
int
-Dispatcher::print_smob (SCM s, SCM p, scm_print_state *)
+Dispatcher::print_smob (SCM p, scm_print_state *) const
{
- Dispatcher *me = (Dispatcher *) SCM_CELL_WORD_1 (s);
scm_puts ("#<Dispatcher ", p);
- scm_write (scm_vector_to_list (me->listeners_), p);
+ scm_write (Lily::hash_table_to_alist (listeners_), p);
scm_puts (">", p);
return 1;
}
This is done by keeping a priority queue of listener lists,
and iteratively send the event to the lowest-priority listener.
- An event is never sent twice to listeners with equal priority.
+ The only case where listeners with equal priority may exist is when
+ two dispatchers are connected for more than one event type. In that
+ case, the respective listeners all have the same priority, making
+ sure that any event is only dispatched at most once for that
+ combination of dispatchers, even if it matches more than one event
+ type.
*/
-IMPLEMENT_LISTENER (Dispatcher, dispatch);
void
Dispatcher::dispatch (SCM sev)
{
- Stream_event *ev = unsmob_stream_event (sev);
- SCM class_symbol = ev->get_property ("class");
- if (!scm_is_symbol (class_symbol))
- {
- warning (_ ("Event class should be a symbol"));
- return;
- }
-
- SCM class_list = scm_call_1 (ly_lily_module_constant ("ly:make-event-class"), class_symbol);
+ Stream_event *ev = unsmob<Stream_event> (sev);
+ SCM class_list = ev->get_property ("class");
if (!scm_is_pair (class_list))
{
- ev->origin ()->warning (_f ("Unknown event class %s", ly_symbol2string (class_symbol).c_str ()));
+ ev->origin ()->warning (_ ("Event class should be a list"));
return;
}
+
#if 0
bool sent = false;
#endif
listener list, and the lowest priority element is repeatedly
extracted and called.
- The priority queue is implemented as a bubble-sorted C
+ The priority queue is implemented as an insertion-sorted C
array. Using the stack instead of native Scheme datastructures
avoids overheads for memory allocation. The queue is usually small
(around 2 elements), so the quadratic sorting time is not a
num_classes--;
else
{
- // bubblesort.
+ // insertion sort.
int prio = scm_to_int (scm_caar (list));
int j;
for (j = i; j > 0 && lists[j - 1].prio > prio; j--)
assert (lists[0].prio > last_priority);
last_priority = lists[0].prio;
- Listener *l = unsmob_listener (scm_cdar (lists[0].list));
- l->listen (ev->self_scm ());
+ SCM l = scm_cdar (lists[0].list);
+ scm_call_1 (l, ev->self_scm ());
#if 0
sent = true;
#endif
#if 0
/* TODO: Uncomment. */
- if (!sent)
- warning (_f ("Junking event: %s", ly_symbol2string (class_symbol).c_str ()));
+ if (!sent)
+ warning (_f ("Junking event: %s", ly_symbol2string (class_symbol).c_str ()));
#endif
}
+bool
+Dispatcher::is_listened_class (SCM cl)
+{
+ for (; scm_is_pair (cl); cl = scm_cdr (cl))
+ {
+ SCM list = scm_hashq_ref (listeners_, scm_car (cl), SCM_EOL);
+ if (scm_is_pair (list))
+ return true;
+ }
+ return false;
+}
+
+static SCM
+accumulate_types (void * /* closure */,
+ SCM key,
+ SCM val,
+ SCM result)
+{
+ if (scm_is_pair (val))
+ return scm_cons (key, result);
+ return result;
+}
+
+SCM
+Dispatcher::listened_types ()
+{
+ return scm_internal_hash_fold ((scm_t_hash_fold_fn) &accumulate_types,
+ NULL, SCM_EOL, listeners_);
+}
+
void
Dispatcher::broadcast (Stream_event *ev)
{
dispatch (ev->self_scm ());
}
+// add_listener will always assign a new priority for each call
void
Dispatcher::add_listener (Listener l, SCM ev_class)
{
- internal_add_listener (l, ev_class, ++priority_count_);
+ add_listener (l.smobbed_copy (), ev_class);
+}
+
+void
+Dispatcher::add_listener (SCM callback, SCM ev_class)
+{
+ internal_add_listener (callback, ev_class, ++priority_count_);
}
inline void
-Dispatcher::internal_add_listener (Listener l, SCM ev_class, int priority)
+Dispatcher::internal_add_listener (SCM callback, SCM ev_class, int priority)
{
- SCM list = scm_hashq_ref (listeners_, ev_class, SCM_EOL);
+ SCM handle = scm_hashq_create_handle_x (listeners_, ev_class, SCM_EOL);
+ SCM list = scm_cdr (handle);
+ // if ev_class is not yet listened to, we go through our list of
+ // source dispatchers and register ourselves there with the priority
+ // we have reserved for this dispatcher. The priority system
+ // usually distributes events in the order events are registered.
+ // The reuse of a previous priority when registering another event
+ // for a dispatcher/dispatcher connection bypasses the normal
+ // ordering, but it is the mechanism by which duplicate broadcasts
+ // of the same event from one dispatcher to another are avoided.
if (!scm_is_pair (list))
{
/* Tell all dispatchers that we listen to, that we want to hear ev_class
for (SCM disp = dispatchers_; scm_is_pair (disp); disp = scm_cdr (disp))
{
int priority = scm_to_int (scm_cdar (disp));
- Dispatcher *d = unsmob_dispatcher (scm_caar (disp));
- d->internal_add_listener (GET_LISTENER (dispatch), ev_class, priority);
+ Dispatcher *d = unsmob<Dispatcher> (scm_caar (disp));
+ d->internal_add_listener (GET_LISTENER (Dispatcher, dispatch).smobbed_copy (),
+ ev_class, priority);
}
listen_classes_ = scm_cons (ev_class, listen_classes_);
}
- SCM entry = scm_cons (scm_from_int (priority), l.smobbed_copy ());
- list = scm_merge (list, scm_list_1 (entry), ly_lily_module_constant ("car<"));
- scm_hashq_set_x (listeners_, ev_class, list);
+ SCM entry = scm_cons (scm_from_int (priority), callback);
+ list = scm_merge (list, scm_list_1 (entry), Lily::car_less);
+ scm_set_cdr_x (handle, list);
}
void
Dispatcher::remove_listener (Listener l, SCM ev_class)
{
- SCM list = scm_hashq_ref (listeners_, ev_class, SCM_EOL);
+ SCM handle = scm_hashq_get_handle (listeners_, ev_class);
- if (list == SCM_EOL)
+ if (scm_is_false (handle))
{
programming_error ("remove_listener called with incorrect class.");
return;
}
+ SCM list = scm_cdr (handle);
// We just remove the listener once.
bool first = true;
SCM dummy = scm_cons (SCM_EOL, list);
SCM e = dummy;
while (scm_is_pair (scm_cdr (e)))
- if (*unsmob_listener (scm_cdadr (e)) == l && first)
+ if (*unsmob<Listener> (scm_cdadr (e)) == l && first)
{
scm_set_cdr_x (e, scm_cddr (e));
first = false;
else
e = scm_cdr (e);
list = scm_cdr (dummy);
- scm_hashq_set_x (listeners_, ev_class, list);
+ scm_set_cdr_x (handle, list);
if (first)
- warning ("Attempting to remove nonexisting listener.");
+ warning (_ ("Attempting to remove nonexisting listener."));
else if (!scm_is_pair (list))
{
/* Unregister with all dispatchers. */
for (SCM disp = dispatchers_; scm_is_pair (disp); disp = scm_cdr (disp))
{
- Dispatcher *d = unsmob_dispatcher (scm_caar (disp));
- d->remove_listener (GET_LISTENER (dispatch), ev_class);
+ Dispatcher *d = unsmob<Dispatcher> (scm_caar (disp));
+ d->remove_listener (GET_LISTENER (Dispatcher, dispatch), ev_class);
}
listen_classes_ = scm_delq_x (ev_class, listen_classes_);
}
void
Dispatcher::register_as_listener (Dispatcher *disp)
{
+ // We are creating and remembering the priority _we_ have with the
+ // foreign dispatcher. All events are dispatched with the same
+ // priority. The result is that, for example, a single event class
+ // will only trigger an event listener once.
int priority = ++disp->priority_count_;
// Don't register twice to the same dispatcher.
- if (scm_assq (disp->self_scm (), dispatchers_) != SCM_BOOL_F)
+ if (scm_is_true (scm_assq (disp->self_scm (), dispatchers_)))
{
- warning ("Already listening to dispatcher, ignoring request");
+ warning (_ ("Already listening to dispatcher, ignoring request"));
return;
}
dispatchers_ = scm_acons (disp->self_scm (), scm_from_int (priority), dispatchers_);
- Listener list = GET_LISTENER (dispatch);
+ SCM list = GET_LISTENER (Dispatcher, dispatch).smobbed_copy ();
for (SCM cl = listen_classes_; scm_is_pair (cl); cl = scm_cdr (cl))
{
disp->internal_add_listener (list, scm_car (cl), priority);
{
dispatchers_ = scm_assq_remove_x (dispatchers_, disp->self_scm ());
- Listener listener = GET_LISTENER (dispatch);
+ Listener listener = GET_LISTENER (Dispatcher, dispatch);
for (SCM cl = listen_classes_; scm_is_pair (cl); cl = scm_cdr (cl))
{
disp->remove_listener (listener, scm_car (cl));
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