Reduce code duplication with with new 'glwrap_lookup' function.

[fips] / glwrap.h

diff --git a/glwrap.h b/glwrap.h
index 81e1e34c9f0ccc11980de3e70caf42366dd501c2..2dc18383c0c864e40e5b033ce67f2f209fe895dd 100644 (file)
--- a/glwrap.h
+++ b/glwrap.h
@@ -22,6 +22,21 @@
 #ifndef GLWRAP_H
 #define GLWRAP_H
 
+/* Lookup a function named 'name' in the underlying, real, libGL.so */
+void *
+glwrap_lookup (char *name);
+
+/* Defer to the real 'function' (from libGL.so) to do the real work.
+ * The symbol is looked up once and cached in a static variable for
+ * future uses.
+ */
+#define GLWRAP_DEFER(function,...) do {                                \
+       static typeof(&function) real_ ## function;             \
+       if (! real_ ## function)                                \
+               real_ ## function = glwrap_lookup (#function);  \
+       real_ ## function(__VA_ARGS__);                         \
+} while (0);
+
 /* Should be called at the end of ever function wrapper for an OpenGL
  * function that ends a frame, (glXSwapBuffers and similar).
  */