incubator-nuttx/libs/libc/uuid/lib_uuid_from_string.c

118 lines
3.4 KiB
C

/****************************************************************************
* libs/libc/uuid/lib_uuid_from_string.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <inttypes.h>
#include <stdio.h>
#include <string.h>
#include <uuid.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* uuid_from_string
*
* Description:
* convert a string representation of an UUID into a binary representation.
*
* See also:
* http://www.opengroup.org/onlinepubs/009629399/uuid_from_string.htm
*
****************************************************************************/
void uuid_from_string(const char *s, uuid_t *u, uint32_t *status)
{
int n;
/* Short-circuit 2 special cases: NULL pointer and empty string. */
if (s == NULL || *s == '\0')
{
uuid_create_nil(u, status);
return;
}
/* Assume the worst. */
if (status != NULL)
{
*status = uuid_s_invalid_string_uuid;
}
/* The UUID string representation has a fixed length. */
if (strnlen(s, UUID_STR_LEN + 1) != UUID_STR_LEN)
{
return;
}
/* We only work with "new" UUIDs. New UUIDs have the form:
* 01234567-89ab-cdef-0123-456789abcdef
* The so called "old" UUIDs, which we don't support, have the form:
* 0123456789ab.cd.ef.01.23.45.67.89.ab
*/
if (s[8] != '-')
{
return;
}
n = sscanf(s,
"%08" SCNx32 "-%04" SCNx16 "-%04" SCNx16
"-%02" SCNx8 "%02" SCNx8
"-%02" SCNx8 "%02" SCNx8 "%02" SCNx8
"%02" SCNx8 "%02" SCNx8 "%02" SCNx8,
&u->time_low, &u->time_mid, &u->time_hi_and_version,
&u->clock_seq_hi_and_reserved, &u->clock_seq_low, &u->node[0],
&u->node[1], &u->node[2], &u->node[3], &u->node[4], &u->node[5]);
/* Make sure we have all conversions. */
if (n != 11)
{
return;
}
/* We have a successful scan. Check semantics... */
n = u->clock_seq_hi_and_reserved;
if ((n & 0x80) != 0x00 && /* variant 0? */
(n & 0xc0) != 0x80 && /* variant 1? */
(n & 0xe0) != 0xc0) /* variant 2? */
{
if (status != NULL)
{
*status = uuid_s_bad_version;
}
}
else
{
if (status != NULL)
{
*status = uuid_s_ok;
}
}
}