proper header added

lib/http_digest.h

+#ifndef __HTTP_DIGEST_H
+#define __HTTP_DIGEST_H
 /***************************************************************************
  *                                  _   _ ____  _     
  *  Project                     ___| | | |  _ \| |    
@@ -41,3 +43,4 @@ CURLdigest Curl_input_digest(struct connectdata *conn, char *header);
 CURLcode Curl_output_digest(struct connectdata *conn,
                             unsigned char *request,
                             unsigned char *uripath);
+#endif

lib/md5.h

+#ifndef __MD5_H
+#define __MD5_H
+/***************************************************************************
+ *                                  _   _ ____  _     
+ *  Project                     ___| | | |  _ \| |    
+ *                             / __| | | | |_) | |    
+ *                            | (__| |_| |  _ <| |___ 
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2003, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at http://curl.haxx.se/docs/copyright.html.
+ * 
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ * $Id$
+ ***************************************************************************/
 
 void Curl_md5it(unsigned char *output,
                 unsigned char *input);
 
+#endif