From c2288a7b88240e4377bfc1c67b44efb58f704a42 Mon Sep 17 00:00:00 2001
From: Julien Olivain <juju@cotds.org>
Date: Mon, 11 May 2020 08:58:30 +0200
Subject: [PATCH] render/egl: include EGL/eglmesaext.h only if present

This patch will make the EGL renderer work on any EGL/GLESv2 driver
providing the EGL_WL_bind_wayland_display extensions.

Mesa used to declare provisional EGL_WL_bind_wayland_display directly
in <EGL/eglext.h>. Then, all unofficial extensions were moved to
<EGL/eglmesaext.h>, to have a cleaner implementation. See:
https://gitlab.freedesktop.org/mesa/mesa/-/commit/ab7bb10a2af711086319ce35815acd797b86fe27

The extension was then approved at Khronos Group, and reached the
official <EGL/eglext.h>. See:
https://www.khronos.org/registry/EGL/extensions/WL/EGL_WL_bind_wayland_display.txt
https://github.com/KhronosGroup/EGL-Registry/commit/aa9b63f3ab18aee92c95786a2478156430f809e4

In order to make sure the renderer will work on any version of any
implementation providing the extension, only include the mesa-specific
header if it's present.

Signed-off-by: Julien Olivain <juju@cotds.org>
---
 include/wlr/config.h.in  | 2 ++
 include/wlr/render/egl.h | 4 ++++
 meson.build              | 5 +++++
 3 files changed, 11 insertions(+)

diff --git a/include/wlr/config.h.in b/include/wlr/config.h.in
index 94273fac..a7691ff9 100644
--- a/include/wlr/config.h.in
+++ b/include/wlr/config.h.in
@@ -1,6 +1,8 @@
 #ifndef WLR_CONFIG_H
 #define WLR_CONFIG_H
 
+#mesondefine WLR_HAS_EGLMESAEXT_H
+
 #mesondefine WLR_HAS_LIBCAP
 
 #mesondefine WLR_HAS_SYSTEMD
diff --git a/include/wlr/render/egl.h b/include/wlr/render/egl.h
index 50432887..c810b08e 100644
--- a/include/wlr/render/egl.h
+++ b/include/wlr/render/egl.h
@@ -16,10 +16,14 @@
 #define EGL_NO_X11
 #endif
 
+#include <wlr/config.h>
+
 #include <EGL/egl.h>
 #include <EGL/eglext.h>
+#if WLR_HAS_EGLMESAEXT_H
 // TODO: remove eglmesaext.h
 #include <EGL/eglmesaext.h>
+#endif
 #include <pixman.h>
 #include <stdbool.h>
 #include <wayland-server-core.h>
diff --git a/meson.build b/meson.build
index 1a160208..a6dad5d6 100644
--- a/meson.build
+++ b/meson.build
@@ -86,6 +86,7 @@ conf_data.set10('WLR_HAS_X11_BACKEND', false)
 conf_data.set10('WLR_HAS_XWAYLAND', false)
 conf_data.set10('WLR_HAS_XCB_ERRORS', false)
 conf_data.set10('WLR_HAS_XCB_ICCCM', false)
+conf_data.set10('WLR_HAS_EGLMESAEXT_H', false)
 
 # Clang complains about some zeroed initializer lists (= {0}), even though they
 # are valid
@@ -109,6 +110,10 @@ pixman = dependency('pixman-1')
 math = cc.find_library('m')
 rt = cc.find_library('rt')
 
+if cc.has_header('EGL/eglmesaext.h', dependencies: egl)
+	conf_data.set10('WLR_HAS_EGLMESAEXT_H', true)
+endif
+
 wlr_files = []
 wlr_deps = [
 	wayland_server,