freebsd-skq/lib/libc/uuid/uuid_compare.c
pfg 9014a6e40c libc: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-25 17:12:48 +00:00

79 lines
2.6 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* 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 <string.h>
#include <uuid.h>
/* A macro used to improve the readability of uuid_compare(). */
#define DIFF_RETURN(a, b, field) do { \
if ((a)->field != (b)->field) \
return (((a)->field < (b)->field) ? -1 : 1); \
} while (0)
/*
* uuid_compare() - compare two UUIDs.
* See also:
* http://www.opengroup.org/onlinepubs/009629399/uuid_compare.htm
*
* NOTE: Either UUID can be NULL, meaning a nil UUID. nil UUIDs are smaller
* than any non-nil UUID.
*/
int32_t
uuid_compare(const uuid_t *a, const uuid_t *b, uint32_t *status)
{
int res;
if (status != NULL)
*status = uuid_s_ok;
/* Deal with NULL or equal pointers. */
if (a == b)
return (0);
if (a == NULL)
return ((uuid_is_nil(b, NULL)) ? 0 : -1);
if (b == NULL)
return ((uuid_is_nil(a, NULL)) ? 0 : 1);
/* We have to compare the hard way. */
DIFF_RETURN(a, b, time_low);
DIFF_RETURN(a, b, time_mid);
DIFF_RETURN(a, b, time_hi_and_version);
DIFF_RETURN(a, b, clock_seq_hi_and_reserved);
DIFF_RETURN(a, b, clock_seq_low);
res = memcmp(a->node, b->node, sizeof(a->node));
if (res)
return ((res < 0) ? -1 : 1);
return (0);
}
#undef DIFF_RETURN