data-loop: add _wait function

Add function to wait for one iteration of the loop. This can be used
by specialized implementations of the data loop, like jack.

pipewire-jack

@@ -1 +1 @@
-Subproject commit 2abcc287627568a88424782c05ff527b5817ba56
+Subproject commit 2736c227a19b1db48dd849af6f7f3e929bb53c00

spa/include/spa/support/loop.h

@@ -162,11 +162,11 @@ struct spa_loop_control_methods {
 
 	/** Perform one iteration of the loop.
 	 * \param ctrl the control
-	 * \param timeout an optional timeout. 0 for no timeout, -1 for infinte
+	 * \param timeout an optional timeout in milliseconds.
-	 *		timeout.
+	 *	0 for no timeout, -1 for infinte timeout.
 	 *
 	 * This function will block
-	 * up to \a timeout and then dispatch the fds with activity.
+	 * up to \a timeout milliseconds and then dispatch the fds with activity.
 	 * The number of dispatched fds is returned.
 	 */
 	int (*iterate) (void *object, int timeout);

src/modules/module-client-node/client-node.c

@@ -1254,8 +1254,8 @@ static void node_initialized(void *data)
 	struct spa_system *data_system = impl->node.data_system;
 	size_t size;
 
-	impl->fds[0] = spa_system_eventfd_create(data_system, SPA_FD_CLOEXEC);
+	impl->fds[0] = spa_system_eventfd_create(data_system, SPA_FD_CLOEXEC | SPA_FD_NONBLOCK);
-	impl->fds[1] = spa_system_eventfd_create(data_system, SPA_FD_CLOEXEC);
+	impl->fds[1] = spa_system_eventfd_create(data_system, SPA_FD_CLOEXEC | SPA_FD_NONBLOCK);
 	impl->other_fds[0] = impl->fds[1];
 	impl->other_fds[1] = impl->fds[0];
 	node->data_source.fd = impl->fds[0];
@@ -1537,7 +1537,7 @@ static void node_peer_added(void *data, struct pw_node *peer)
 		pw_log_debug(NAME " %p: can't ensure mem: %m", this);
 		return;
 	}
-	pw_log_debug(NAME " %p: peer %p %u added %u", &impl->this, peer,
+	pw_log_debug(NAME " %p: peer %p id:%u added mem_id:%u", &impl->this, peer,
 			peer->info.id, m->id);
 
 	if (this->resource == NULL)

src/pipewire/data-loop.c

@@ -32,6 +32,29 @@
 
 #define NAME "data-loop"
 
+SPA_EXPORT
+int pw_data_loop_wait(struct pw_data_loop *this, int timeout)
+{
+	int res;
+
+	while (true) {
+		if (!this->running)
+			return -ECANCELED;
+		if ((res = pw_loop_iterate(this->loop, timeout)) < 0) {
+			if (errno == EINTR)
+				continue;
+		}
+		break;
+	}
+	return res;
+}
+
+SPA_EXPORT
+void pw_data_loop_exit(struct pw_data_loop *this)
+{
+	this->running = false;
+}
+
 static void *do_loop(void *user_data)
 {
 	struct pw_data_loop *this = user_data;
@@ -41,10 +64,14 @@ static void *do_loop(void *user_data)
 	pw_loop_enter(this->loop);
 
 	while (this->running) {
-		if ((res = pw_loop_iterate(this->loop, -1)) < 0)
+		if ((res = pw_loop_iterate(this->loop, -1)) < 0) {
-			pw_log_warn(NAME" %p: iterate error %d (%s)",
+			if (errno == EINTR)
+				continue;
+			pw_log_error(NAME" %p: iterate error %d (%s)",
 					this, res, spa_strerror(res));
+		}
 	}
+
 	pw_log_debug(NAME" %p: leave thread", this);
 	pw_loop_leave(this->loop);
 
@@ -64,6 +91,7 @@ static void do_stop(void *data, uint64_t count)
  *
  * \memberof pw_data_loop
  */
+SPA_EXPORT
 struct pw_data_loop *pw_data_loop_new(struct pw_properties *properties)
 {
 	struct pw_data_loop *this;
@@ -111,6 +139,7 @@ error_cleanup:
  * \param loop the data loop to destroy
  * \memberof pw_data_loop
  */
+SPA_EXPORT
 void pw_data_loop_destroy(struct pw_data_loop *loop)
 {
 	pw_log_debug(NAME" %p: destroy", loop);
@@ -124,6 +153,7 @@ void pw_data_loop_destroy(struct pw_data_loop *loop)
 	free(loop);
 }
 
+SPA_EXPORT
 void pw_data_loop_add_listener(struct pw_data_loop *loop,
 			       struct spa_hook *listener,
 			       const struct pw_data_loop_events *events,
@@ -146,6 +176,7 @@ pw_data_loop_get_loop(struct pw_data_loop *loop)
  *
  * \memberof pw_data_loop
  */
+SPA_EXPORT
 int pw_data_loop_start(struct pw_data_loop *loop)
 {
 	if (!loop->running) {
@@ -169,6 +200,7 @@ int pw_data_loop_start(struct pw_data_loop *loop)
  *
  * \memberof pw_data_loop
  */
+SPA_EXPORT
 int pw_data_loop_stop(struct pw_data_loop *loop)
 {
 	if (loop->running) {
@@ -185,6 +217,7 @@ int pw_data_loop_stop(struct pw_data_loop *loop)
  *
  * \memberof pw_data_loop
  */
+SPA_EXPORT
 bool pw_data_loop_in_thread(struct pw_data_loop * loop)
 {
 	return pthread_equal(loop->thread, pthread_self());

src/pipewire/data-loop.h

@@ -59,6 +59,13 @@ void pw_data_loop_add_listener(struct pw_data_loop *loop,
 			       const struct pw_data_loop_events *events,
 			       void *data);
 
+/** wait for activity on the loop up to \a timeout milliseconds.
+ * Should be called from the loop function */
+int pw_data_loop_wait(struct pw_data_loop *loop, int timeout);
+
+/** make sure the thread will exit. Can be called from a loop callback */
+void pw_data_loop_exit(struct pw_data_loop *loop);
+
 /** Get the loop implementation of this data loop */
 struct pw_loop *
 pw_data_loop_get_loop(struct pw_data_loop *loop);