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/**
* Copyright (c) 2019-2021 Chris Hiszpanski. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*/
/**
* Pseudo-random univerally-unique identifier generator [^RFC4122].
*
* [^RFC4122]: https://tools.ietf.org/html/rfc4122#section-4.4
*/
#include <stdio.h>
#include <stdlib.h>
#include "prng.h"
#include "uuid.h"
/**
* Generate a pseudo-random UUID.
*
* \return Populated UUID.
*/
struct uuid uuid_create() {
struct uuid u;
// fill with randomness
prng(&u, sizeof(u));
// set reserved and version bits
u.clk_seq_hi_and_reserved = (u.clk_seq_hi_and_reserved & 0x3F) | 0x80;
u.time_hi_and_version = (u.time_hi_and_version & 0x0FFF) | 0x4000;
return u;
}
/**
* Generate pseudorandom UUID (as a string)
*
* \param s Destination string memory.
*
*/
void uuid_create_str(char s[UUID_STR_LEN]) {
struct uuid u = uuid_create();
sprintf(s, "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
u.time_low,
u.time_mid,
u.time_hi_and_version,
u.clk_seq_hi_and_reserved,
u.clk_seq_low,
u.node[0],
u.node[1],
u.node[2],
u.node[3],
u.node[4],
u.node[5]
);
}
/* vim: set expandtab ts=8 sw=4 tw=0 : */
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