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/* Copyright (C) 2020 C. McEnroe <june@causal.agency>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <sysexits.h>
typedef unsigned char byte;
static const char *uuidGen(void) {
byte uuid[16];
arc4random_buf(uuid, sizeof(uuid));
uuid[6] &= 0x0F;
uuid[6] |= 0x40;
uuid[8] &= 0x3F;
uuid[8] |= 0x80;
static char str[sizeof("00000000-0000-0000-0000-000000000000")];
snprintf(
str, sizeof(str),
"%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
uuid[0], uuid[1], uuid[2], uuid[3],
uuid[4], uuid[5], uuid[6], uuid[7],
uuid[8], uuid[9], uuid[10], uuid[11],
uuid[12], uuid[13], uuid[14], uuid[15]
);
return str;
}
int main(void) {
printf("%s\n", uuidGen());
}
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