Completed ZString::compare method.

ZString.cpp

@@ -1,3 +1,4 @@
+
 #include "ZString.h"
 #include "Log.h"
 #include "Exception.h"
@@ -251,7 +252,23 @@ namespace coreutils {
    }
 
    int ZString::compare(ZString zstring) {
-      
+      char *end1 = data + length;
+      char *end2 = zstring.getData() + getLength();
+      char *cursor1 = cursor;
+      char *cursor2 = zstring.getCursor();
+      while((cursor1 < end1) && (cursor2 < end2)) {
+	 if(*cursor1 < *cursor2)
+	   return -1;
+	 if(*cursor1 > *cursor2)
+	   return 1;
+	 ++cursor1;
+	 ++cursor2;
+      }
+      if((cursor1 == end1) && (cursor2 != end2))
+	return -1;
+      if((cursor2 == end2) && (cursor1 != end1))
+	return 1;
+      return 0;      
    }
       
    bool ZString::equals(const char *value) {