libmisc/uuid/isnull.c

0001 /*
0002  * isnull.c --- Check whether or not the UUID is null
0003  *
0004  * Copyright (C) 1996, 1997 Theodore Ts'o.
0005  *
0006  * %Begin-Header%
0007  * Redistribution and use in source and binary forms, with or without
0008  * modification, are permitted provided that the following conditions
0009  * are met:
0010  * 1. Redistributions of source code must retain the above copyright
0011  *    notice, and the entire permission notice in its entirety,
0012  *    including the disclaimer of warranties.
0013  * 2. Redistributions in binary form must reproduce the above copyright
0014  *    notice, this list of conditions and the following disclaimer in the
0015  *    documentation and/or other materials provided with the distribution.
0016  * 3. The name of the author may not be used to endorse or promote
0017  *    products derived from this software without specific prior
0018  *    written permission.
0019  *
0020  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
0021  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
0022  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
0023  * WHICH ARE HEREBY DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE
0024  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0025  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
0026  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
0027  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
0028  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
0029  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
0030  * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
0031  * DAMAGE.
0032  * %End-Header%
0033  */
0034
0035 #ifdef HAVE_CONFIG_H
0036 #include "config.h"
0037 #endif
0038
0039 #include "uuidP.h"
0040
0041 /* Returns 1 if the uuid is the NULL uuid */
0042 int uuid_is_null(const uuid_t uu)
0043 {
0044     const unsigned char     *cp;
0045     int         i;
0046
0047     for (i=0, cp = uu; i < 16; i++)
0048         if (*cp++)
0049             return 0;
0050     return 1;
0051 }
0052