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Diffstat (limited to 'lib/libc/uuid/uuid_is_nil.c')
-rw-r--r-- | lib/libc/uuid/uuid_is_nil.c | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/lib/libc/uuid/uuid_is_nil.c b/lib/libc/uuid/uuid_is_nil.c new file mode 100644 index 0000000..ee18653 --- /dev/null +++ b/lib/libc/uuid/uuid_is_nil.c @@ -0,0 +1,54 @@ +/*- + * Copyright (c) 2002,2005 Marcel Moolenaar + * Copyright (c) 2002 Hiten Mahesh Pandya + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#include <uuid.h> + +/* + * uuid_is_nil() - return whether the UUID is a nil UUID. + * See also: + * http://www.opengroup.org/onlinepubs/009629399/uuid_is_nil.htm + */ +int32_t +uuid_is_nil(const uuid_t *u, uint32_t *status) +{ + const uint32_t *p; + + if (status) + *status = uuid_s_ok; + + if (!u) + return (1); + + /* + * Pick the largest type that has equivalent alignment constraints + * as an UUID and use it to test if the UUID consists of all zeroes. + */ + p = (const uint32_t*)u; + return ((p[0] == 0 && p[1] == 0 && p[2] == 0 && p[3] == 0) ? 1 : 0); +} |