screencast: pipewire try no to die on changed dimensions

include/pipewire_screencast.h

@@ -8,6 +8,8 @@
 
 void xdpw_pwr_import_buffer(struct xdpw_screencast_instance *cast);
 void xdpw_pwr_export_buffer(struct xdpw_screencast_instance *cast);
+void xdpw_pwr_destroy_shm_buffer(struct xdpw_screencast_instance *cast,
+		struct pw_buffer *buffer);
 void pwr_update_stream_param(struct xdpw_screencast_instance *cast);
 void xdpw_pwr_stream_create(struct xdpw_screencast_instance *cast);
 void xdpw_pwr_stream_destroy(struct xdpw_screencast_instance *cast);

src/screencast/pipewire_screencast.c

@@ -149,15 +149,19 @@ static void pwr_handle_stream_add_buffer(void *data, struct pw_buffer *buffer) {
 }
 
 static void pwr_handle_stream_remove_buffer(void *data, struct pw_buffer *buffer) {
+	struct xdpw_screencast_instance *cast = data;
 	struct spa_data *d;
 
 	logprint(TRACE, "pipewire: remove buffer event handle");
 
 	d = buffer->buffer->datas;
+	if (buffer == cast->current_pw_buffer) {
+		logprint(TRACE, "pipewire: can't remove buffer. still in use");
+		return;
+	}
 	switch (d[0].type) {
 	case SPA_DATA_MemFd:
-		wl_buffer_destroy(d[0].data);
-		close(d[0].fd);
+		xdpw_pwr_destroy_shm_buffer(cast, buffer);
 		break;
 	default:
 		break;
@@ -179,6 +183,7 @@ void xdpw_pwr_import_buffer(struct xdpw_screencast_instance *cast) {
 
 	if ((pw_buf = pw_stream_dequeue_buffer(cast->stream)) == NULL) {
 		logprint(WARN, "pipewire: out of buffers");
+		cast->simple_frame.buffer = NULL;
 		return;
 	}
 
@@ -225,11 +230,24 @@ void xdpw_pwr_export_buffer(struct xdpw_screencast_instance *cast) {
 	logprint(TRACE, "pipewire: y_invert %d", cast->simple_frame.y_invert);
 	logprint(TRACE, "********************");
 
-	pw_stream_queue_buffer(cast->stream, pw_buf);
+	if (cast->current_pw_buffer) {
+		pw_stream_queue_buffer(cast->stream, pw_buf);
+	} else {
+		xdpw_pwr_destroy_shm_buffer(cast, pw_buf);
+	}
 
 	cast->current_pw_buffer = NULL;
 }
 
+void xdpw_pwr_destroy_shm_buffer(struct xdpw_screencast_instance *cast, struct pw_buffer *buffer) {
+	struct spa_data *d;
+
+	d = buffer->buffer->datas;
+	wl_buffer_destroy(d[0].data);
+	d[0].data = NULL;
+	close(d[0].fd);
+}
+
 void pwr_update_stream_param(struct xdpw_screencast_instance *cast) {
 	logprint(TRACE, "pipewire: stream update parameters");
 	struct pw_stream *stream = cast->stream;