1/*-
2 * Copyright (c) 2015 M. Warner Losh <imp@FreeBSD.org>
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 *
25 * $FreeBSD$
26 */
27
28
29/*
30 * Note: some comments taken from lib/libc/uuid/uuid_to_string.c
31 * Copyright (c) 2002,2005 Marcel Moolenaar
32 * Copyright (c) 2002 Hiten Mahesh Pandya
33 */
34
35#include <stand.h>
36#include <uuid.h>
37
38/*
39 * Dump len characters into *buf from val as hex and update *buf
40 */
41static void
42tohex(char **buf, int len, uint32_t val)
43{
44	static const char *hexstr = "0123456789abcdef";
45	char *walker = *buf;
46	int i;
47
48	for (i = len - 1; i >= 0; i--) {
49		walker[i] = hexstr[val & 0xf];
50		val >>= 4;
51	}
52	*buf = walker + len;
53}
54
55/*
56 * uuid_to_string() - Convert a binary UUID into a string representation.
57 * See also:
58 *	http://www.opengroup.org/onlinepubs/009629399/uuid_to_string.htm
59 *
60 * NOTE: The references given above do not have a status code for when
61 *	 the string could not be allocated. The status code has been
62 *	 taken from the Hewlett-Packard implementation.
63 *
64 * NOTE: we don't support u == NULL for a nil UUID, sorry.
65 *
66 * NOTE: The sequence field is in big-endian, while the time fields are in
67 *	 native byte order.
68 *
69 *	 hhhhhhhh-hhhh-hhhh-bbbb-bbbbbbbbbbbb
70 *	 01234567-89ab-cdef-0123-456789abcdef
71 */
72void
73uuid_to_string(const uuid_t *u, char **s, uint32_t *status)
74{
75	uuid_t nil;
76	char *w;
77
78	if (status != NULL)
79		*status = uuid_s_ok;
80	if (s == NULL)	/* Regular version does this odd-ball behavior too */
81		return;
82	w = *s = malloc(37);
83	if (*s == NULL) {
84		if (status != NULL)
85			*status = uuid_s_no_memory;
86		return;
87	}
88	if (u == NULL) {
89		u = &nil;
90		uuid_create_nil(&nil, NULL);
91	}
92	/* native */
93	tohex(&w, 8, u->time_low);
94	*w++ = '-';
95	tohex(&w, 4, u->time_mid);
96	*w++ = '-';
97	tohex(&w, 4, u->time_hi_and_version);
98	*w++ = '-';
99	/* Big endian, so do a byte at a time */
100	tohex(&w, 2, u->clock_seq_hi_and_reserved);
101	tohex(&w, 2, u->clock_seq_low);
102	*w++ = '-';
103	tohex(&w, 2, u->node[0]);
104	tohex(&w, 2, u->node[1]);
105	tohex(&w, 2, u->node[2]);
106	tohex(&w, 2, u->node[3]);
107	tohex(&w, 2, u->node[4]);
108	tohex(&w, 2, u->node[5]);
109	*w++ = '\0';
110}
111