Zabbix

/*

** Zabbix

** Copyright (C) 2001-2023 Zabbix SIA

**

** 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 2 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, write to the Free Software

** Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

**/

​

#include "zbxalgo.h"

#include "algodefs.h"

​

#include "zbxstr.h"

#include "zbxnum.h"

​

typedef unsigned char uchar;

​

/*

 * modified FNV hash function (see http://www.isthe.com/chongo/tech/comp/fnv/)

 */

zbx_hash_t  zbx_hash_modfnv(const void *data, size_t len, zbx_hash_t seed)

{

    const uchar *p = (const uchar *)data;

​

    zbx_hash_t  hash;

​

    hash = 2166136261u ^ seed;

​

    while (len-- >= 1)

    {

        hash = (hash ^ *(p++)) * 16777619u;

    }

​

    hash += hash << 13;

    hash ^= hash >> 7;

    hash += hash << 3;

    hash ^= hash >> 17;

    hash += hash << 5;

​

    return hash;

}

​

/*

 * see http://xoshiro.di.unimi.it/splitmix64.c

 */

zbx_hash_t  zbx_hash_splittable64(const void *data)

{

    zbx_uint64_t    value = *(const zbx_uint64_t *)data;

​

    value ^= value >> 30;

    value *= __UINT64_C(0xbf58476d1ce4e5b9);

    value ^= value >> 27;

    value *= __UINT64_C(0x94d049bb133111eb);