~kennylevinsen/wlavu: Only schedule frame callback from on_process

d8ef3dba467dcc07e07f7dfb7458d86dade5cbb6 — Kenny Levinsen 7 months ago 526aec5 master

Only schedule frame callback from on_process

draw was called in the pipewire on_process callback, but this is not
safe as libpipewire runs on_process on a separate thread.

Instead, kickstart a frame callback loop if needed and let the
Wayland-side drive drawing on the main thread.

patch browse .tar.gz

1 files changed, 10 insertions(+), 3 deletions(-)

M main.c

M main.c => main.c +10 -3

@@ 488,7 488,14 @@ static void on_process(void *userdata) {
 	ctx->last_val = ctx->val;
 	ctx->last_peak = ctx->peak;
 	ctx->dirty = true;
-	draw(ctx);
+
+	if (!ctx->pending) {
+		ctx->pending = true;
+		struct wl_callback *callback = wl_surface_frame(ctx->surface);
+		wl_callback_add_listener(callback, &frame_listener, ctx);
+		wl_surface_commit(ctx->surface);
+		wl_display_flush(ctx->display);
+	}
 }
 
 static const struct pw_stream_events stream_events = {


@@ 626,8 633,8 @@ static int display_dispatch(struct pollfd *pfd, int polln, struct wl_display *di
 	}
 
 	pfd[EVENT_LOOP_WAYLAND].events = POLLOUT;
-	while (wl_display_flush(display) == -1) {
-		if (errno != EAGAIN && errno != EPIPE) {
+	while (wl_display_flush(display) == -1 && errno != EPIPE) {
+		if (errno != EAGAIN) {
 			wl_display_cancel_read(display);
 			return -1;
 		}