Fix a problem where the cloud layers suddenly change color when looking towards the sun

[simgear.git] / simgear / screen / extensions.cxx

diff --git a/simgear/screen/extensions.cxx b/simgear/screen/extensions.cxx
index 99a170866c2b38819139b922f8dcd809dda7070b..75f7d11e7655594004f6fc3340564dc03635469a 100644 (file)
--- a/simgear/screen/extensions.cxx
+++ b/simgear/screen/extensions.cxx
@@ -26,13 +26,16 @@
 
 #include "extensions.hxx"
 
-bool SGSearchExtensionsString(char *extString, char *extName) {
+static bool SGSearchExtensionsString(char *extString, char *extName) {
     // Returns GL_TRUE if the *extName string appears in the *extString string,
     // surrounded by white spaces, or GL_FALSE otherwise.
 
     char *p, *end;
     int n, extNameLen;
 
+    if ((extString == NULL) || (extName == NULL))
+        return false;
+
     extNameLen = strlen(extName);
 
     p=extString;