X-Git-Url: https://git.cworth.org/git?a=blobdiff_plain;ds=sidebyside;f=glaze-gl.c;fp=glaze-gl.c;h=7248876b75da4940ee83e71430b9647f41ef801d;hb=6cfcdb728c0a088cc12bb3eb93d78b2a9915969b;hp=453d4606f2be1320b009630bf1e041960b190afc;hpb=e67ec0f4f055ad6b41fb17024cb4496b66054ada;p=glaze

diff --git a/glaze-gl.c b/glaze-gl.c
index 453d460..7248876 100644
--- a/glaze-gl.c
+++ b/glaze-gl.c
@@ -31,6 +31,8 @@
 void *libgl_handle;
 void *wrapper_handle;
 
+#define STRNCMP_LITERAL(str, literal) strncmp (str, literal, sizeof (literal) - 1)
+
 static void
 open_libgl_handle (void)
 {
@@ -104,8 +106,29 @@ glaze_init (void)
 static void *
 resolve (const char *name)
 {
+	static int before_first_gl_call = 1;
 	void *symbol;
 
+	if (before_first_gl_call &&
+	    STRNCMP_LITERAL (name, "gl") == 0 &&
+	    STRNCMP_LITERAL (name, "glX") != 0)
+	{
+		char *callback_name = getenv ("GLAZE_FIRST_GL_CALL_CALLBACK");
+		if (callback_name) {
+			void (*callback) (void) = dlsym (wrapper_handle,
+							 callback_name);
+			if (callback) {
+				(callback) ();
+			} else {
+				fprintf (stderr,
+					 "Error: Failed to find function %s "
+					 "in GLAZE_WRAPPER library.\n",
+					 callback_name);
+			}
+		}
+		before_first_gl_call = 0;
+	}
+
 	/* The wrapper gets first choice on all symbols. */
 	symbol = dlsym (wrapper_handle, name);
 	if (symbol)