cogl: Add the infrastructure for checking for winsys extensions

This adds the framework needed to check for winsys specific extensions
(such as GLX extensions) using a similar mechanism to the
cogl-feature-functions header. There is a separate
cogl-winsys-feature-functions header which will contain macros to list
the extensions and functions. cogl_create_context_winsys now calls
_cogl_feature_check for each of these functions. _cogl_feature_check
has had to be changed to accept the driver prefix as the first
parameter so that it can prepend "GLX" rather than "GL" in this case.

1 files changed, 2 insertions, 1 deletions

diff --git a/cogl/cogl-feature-private.h b/cogl/cogl-feature-private.h
index 2221ec03..133d588e 100644
--- a/cogl/cogl-feature-private.h
+++ b/cogl/cogl-feature-private.h
@@ -67,7 +67,8 @@ struct _CoglFeatureData
   const CoglFeatureFunction *functions;
 };
 
-gboolean _cogl_feature_check (const CoglFeatureData *data,
+gboolean _cogl_feature_check (const char *driver_prefix,
+                              const CoglFeatureData *data,
                               unsigned int gl_major, unsigned int gl_minor,
                               const char *extensions_string);