(svn r11025) -Fix: safeguard StrEmpty from calls with NULL.

src/string.h

@@ -49,7 +49,7 @@ enum CharSetFilter {
 void strtolower(char *str);
 
 
-static inline bool StrEmpty(const char *s) { return s[0] == '\0'; }
+static inline bool StrEmpty(const char *s) { return s == NULL || s[0] == '\0'; }
 
 
 /** Get the length of a string, within a limited buffer */