uuid_from_string.c revision 106184 
1/*-
2 * Copyright (c) 2002 Marcel Moolenaar
3 * Copyright (c) 2002 Hiten Mahesh Pandya
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 * $FreeBSD: head/lib/libc/uuid/uuid_from_string.c 106184 2002-10-30 03:51:00Z marcel $
28 */
29
30#include <stdio.h>
31#include <string.h>
32#include <uuid.h>
33
34/*
35 * uuid_from_string() - convert a string representation of an UUID into
36 *			a binary representation.
37 * See also:
38 *	http://www.opengroup.org/onlinepubs/009629399/uuid_from_string.htm
39 *	http://www.transarc.ibm.com/Library/documentation/dce/1.1/uuid_from_string.html
40 *
41 * NOTE: The sequence field is in big-endian, while the time fields are in
42 *	 native byte order.
43 */
44void
45uuid_from_string(const char *s, uuid_t *u, uint32_t *status)
46{
47	int n;
48
49	/* Short-circuit 2 special cases: NULL pointer and empty string. */
50	if (s == NULL || *s == '\0') {
51		uuid_create_nil(u, status);
52		return;
53	}
54
55	/* Assume the worst. */
56	if (status != NULL)
57		*status = uuid_s_invalid_string_uuid;
58
59	/* The UUID string representation has a fixed length. */
60	if (strlen(s) != 36)
61		return;
62
63	/*
64	 * We only work with "new" UUIDs. New UUIDs have the form:
65	 *	01234567-89ab-cdef-0123-456789abcdef
66	 * The so called "old" UUIDs, which we don't support, have the form:
67	 *	0123456789ab.cd.ef.01.23.45.67.89.ab
68	 */
69	if (s[8] != '-')
70		return;
71
72	n = sscanf(s,
73	    "%8x-%4hx-%4hx-%2hhx%2hhx-%2hhx%2hhx%2hhx%2hhx%2hhx%2hhx",
74	    &u->time_low, &u->time_mid, &u->time_hi_and_version,
75	    &u->clock_seq_hi_and_reserved, &u->clock_seq_low, &u->node[0],
76	    &u->node[1], &u->node[2], &u->node[3], &u->node[4], &u->node[5]);
77
78	/* Make sure we have all conversions. */
79	if (n != 11)
80		return;
81
82	/* We have a successful scan. Check semantics... */
83	n = u->clock_seq_hi_and_reserved;
84	if ((n & 0x80) != 0x00 &&			/* variant 0? */
85	    (n & 0xc0) != 0x80 &&			/* variant 1? */
86	    (n & 0xe0) != 0xc0) {			/* variant 2? */
87		if (status != NULL)
88			*status = uuid_s_bad_version;
89	} else {
90		if (status != NULL)
91			*status = uuid_s_ok;
92	}
93}
94