uuid.c revision efc6f628e15de95bcd13e4f0ee223cb42115d520 
1/*
2 * uuid.c -- utility routines for manipulating UUID's.
3 */
4
5#include <stdio.h>
6#include <string.h>
7#include <ext2fs/ext2_types.h>
8
9#include "e2p.h"
10
11struct uuid {
12	__u32	time_low;
13	__u16	time_mid;
14	__u16	time_hi_and_version;
15	__u16	clock_seq;
16	__u8	node[6];
17};
18
19/* Returns 1 if the uuid is the NULL uuid */
20int e2p_is_null_uuid(void *uu)
21{
22	__u8 	*cp;
23	int	i;
24
25	for (i=0, cp = uu; i < 16; i++)
26		if (*cp++)
27			return 0;
28	return 1;
29}
30
31static void e2p_unpack_uuid(void *in, struct uuid *uu)
32{
33	__u8	*ptr = in;
34	__u32	tmp;
35
36	tmp = *ptr++;
37	tmp = (tmp << 8) | *ptr++;
38	tmp = (tmp << 8) | *ptr++;
39	tmp = (tmp << 8) | *ptr++;
40	uu->time_low = tmp;
41
42	tmp = *ptr++;
43	tmp = (tmp << 8) | *ptr++;
44	uu->time_mid = tmp;
45
46	tmp = *ptr++;
47	tmp = (tmp << 8) | *ptr++;
48	uu->time_hi_and_version = tmp;
49
50	tmp = *ptr++;
51	tmp = (tmp << 8) | *ptr++;
52	uu->clock_seq = tmp;
53
54	memcpy(uu->node, ptr, 6);
55}
56
57void e2p_uuid_to_str(void *uu, char *out)
58{
59	struct uuid uuid;
60
61	e2p_unpack_uuid(uu, &uuid);
62	sprintf(out,
63		"%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
64		uuid.time_low, uuid.time_mid, uuid.time_hi_and_version,
65		uuid.clock_seq >> 8, uuid.clock_seq & 0xFF,
66		uuid.node[0], uuid.node[1], uuid.node[2],
67		uuid.node[3], uuid.node[4], uuid.node[5]);
68}
69
70const char *e2p_uuid2str(void *uu)
71{
72	static char buf[80];
73
74	if (e2p_is_null_uuid(uu))
75		return "<none>";
76	e2p_uuid_to_str(uu, buf);
77	return buf;
78}
79
80