/* * Copyright (c) 2008-2021 Jonathan Schleifer <js@nil.im> * * All rights reserved. * * This file is part of ObjFW. It may be distributed under the terms of the * Q Public License 1.0, which can be found in the file LICENSE.QPL included in * the packaging of this file. * * Alternatively, it may be distributed under the terms of the GNU General * Public License, either version 2 or 3, which can be found in the file * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this * file. */ #include "config.h" #import "crc32.h" #define CRC32_MAGIC 0xEDB88320 uint32_t of_crc32(uint32_t crc, const void *bytes_, size_t length) { const unsigned char *bytes = bytes_; for (size_t i = 0; i < length; i++) { crc ^= bytes[i]; for (uint8_t j = 0; j < 8; j++) crc = (crc >> 1) ^ (CRC32_MAGIC & (~(crc & 1) + 1)); } return crc; }