e2fsprogs/lib/e2p/uuid.c
Theodore Ts'o b116e781f6 Fix bug which could cause dumpe2fs to rarely fail to print a UUID
uuid.c (e2p_is_null_uuid): Fix really stupid bug which could cause dumpe2fs
to fail to display a the journal or hash seed UUID.  (Thanks to Guillaume
Chambraud for pointing this out.)

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2006-04-22 04:32:36 -04:00

80 lines
1.4 KiB
C

/*
* uuid.c -- utility routines for manipulating UUID's.
*/
#include <stdio.h>
#include <string.h>
#include <ext2fs/ext2_types.h>
#include "e2p.h"
struct uuid {
__u32 time_low;
__u16 time_mid;
__u16 time_hi_and_version;
__u16 clock_seq;
__u8 node[6];
};
/* Returns 1 if the uuid is the NULL uuid */
int e2p_is_null_uuid(void *uu)
{
__u8 *cp;
int i;
for (i=0, cp = uu; i < 16; i++)
if (*cp++)
return 0;
return 1;
}
static void e2p_unpack_uuid(void *in, struct uuid *uu)
{
__u8 *ptr = in;
__u32 tmp;
tmp = *ptr++;
tmp = (tmp << 8) | *ptr++;
tmp = (tmp << 8) | *ptr++;
tmp = (tmp << 8) | *ptr++;
uu->time_low = tmp;
tmp = *ptr++;
tmp = (tmp << 8) | *ptr++;
uu->time_mid = tmp;
tmp = *ptr++;
tmp = (tmp << 8) | *ptr++;
uu->time_hi_and_version = tmp;
tmp = *ptr++;
tmp = (tmp << 8) | *ptr++;
uu->clock_seq = tmp;
memcpy(uu->node, ptr, 6);
}
void e2p_uuid_to_str(void *uu, char *out)
{
struct uuid uuid;
e2p_unpack_uuid(uu, &uuid);
sprintf(out,
"%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
uuid.time_low, uuid.time_mid, uuid.time_hi_and_version,
uuid.clock_seq >> 8, uuid.clock_seq & 0xFF,
uuid.node[0], uuid.node[1], uuid.node[2],
uuid.node[3], uuid.node[4], uuid.node[5]);
}
const char *e2p_uuid2str(void *uu)
{
static char buf[80];
if (e2p_is_null_uuid(uu))
return "<none>";
e2p_uuid_to_str(uu, buf);
return buf;
}