Make EGL support optional

It is perfectly possible to build Mesa3D with just OpenGL support, and
use with GLX in X.org, without having EGL/OpenGLES support.

However, libepoxy currently unconditionally requires EGL support in its
configure.ac, which causes a build failure when Mesa3D only provides
full OpenGL support:

checking for EGL... no
configure: error: Package requirements (egl) were not met:

Package egl was not found in the pkg-config search path.
Perhaps you should add the directory containing `egl.pc'
to the PKG_CONFIG_PATH environment variable
Package 'egl', required by 'world', not found

This commit fixes that by:

 - Adjusting the configure.ac to add a --{enable,disable}-egl option
   handled in the exact same way as --{enable,disable}-glx

 - Adjusting the meson build logic in the same way.

 - Adjusting src/dispatch_common.h to define PLATFORM_HAS_EGL correctly,
   which allows to not include any EGL related header file if EGL
   support is not enabled.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

1 files changed, 18 insertions, 3 deletions

diff --git a/meson.build b/meson.build
index 5435f45..226152e 100644
--- a/meson.build
+++ b/meson.build
@@ -51,26 +51,41 @@ elif enable_glx == 'no'
   build_glx = false
 endif
 
+enable_egl = get_option('enable-egl')
+if enable_egl == 'auto'
+  if host_system == 'windows'
+    build_egl = false
+  elif host_system == 'darwin'
+    build_egl = false
+  elif host_system == 'android'
+    build_egl = false
+  else
+    build_egl = true
+  endif
+elif enable_egl == 'yes'
+  build_egl = true
+elif enable_egl == 'no'
+  build_egl = false
+endif
+
 # The remaining platform specific API for GL/GLES are enabled
 # depending on the platform we're building for
 if host_system == 'windows'
-  build_egl = false
   build_apple = false
   build_wgl = true
   has_znow = true
 elif host_system == 'darwin'
-  build_egl = false
   build_apple = true
   build_wgl = false
   has_znow = false
 else
-  build_egl = true
   build_apple = false
   build_wgl = false
   has_znow = true
 endif
 
 conf.set10('ENABLE_GLX', build_glx)
+conf.set10('ENABLE_EGL', build_egl)
 
 # Compiler flags, taken from the Xorg macros
 if cc.get_id() == 'msvc'