From baf1e4f674033d65ef2375601ab21936ad426340 Mon Sep 17 00:00:00 2001
From: Kirill Primak <vyivel@eclair.cafe>
Date: Sun, 11 Feb 2024 10:37:12 +0300
Subject: [PATCH] backend/wayland: don't ack a configure event too early

Postpone sending xdg_surface.ack_configure until the guest compositor
commits a buffer, if at all.

Also see
https://gitlab.freedesktop.org/wayland/wayland-protocols/-/issues/128.
---
 backend/wayland/output.c  | 8 +++++++-
 include/backend/wayland.h | 3 +++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/backend/wayland/output.c b/backend/wayland/output.c
index ff58cc37..a783abe5 100644
--- a/backend/wayland/output.c
+++ b/backend/wayland/output.c
@@ -588,6 +588,11 @@ static bool output_commit(struct wlr_output *wlr_output,
 				output->surface);
 		}
 
+		if (output->has_configure_serial) {
+			xdg_surface_ack_configure(output->xdg_surface, output->configure_serial);
+			output->has_configure_serial = false;
+		}
+
 		wl_surface_commit(output->surface);
 
 		if (wp_feedback != NULL) {
@@ -742,7 +747,8 @@ static void xdg_surface_handle_configure(void *data,
 	assert(output && output->xdg_surface == xdg_surface);
 
 	output->configured = true;
-	xdg_surface_ack_configure(xdg_surface, serial);
+	output->has_configure_serial = true;
+	output->configure_serial = serial;
 
 	int32_t req_width = output->wlr_output.width;
 	int32_t req_height = output->wlr_output.height;
diff --git a/include/backend/wayland.h b/include/backend/wayland.h
index 192891b4..4f9f382b 100644
--- a/include/backend/wayland.h
+++ b/include/backend/wayland.h
@@ -95,7 +95,10 @@ struct wlr_wl_output {
 	// 0 if not requested
 	int32_t requested_width, requested_height;
 
+	uint32_t configure_serial;
+	bool has_configure_serial;
 	bool configured;
+
 	uint32_t enter_serial;
 
 	struct {