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/*
* Copyright (c) 2017 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* 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;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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 COPYRIGHT
* OWNER OR CONTRIBUTORS 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.
*
* Authors: Giacomo Travaglini
*/
#ifndef __BASE_CRC_HH__
#define __BASE_CRC_HH__
#include "base/bitfield.hh"
/**
* Evaluate the CRC32 of the first size bytes of a data buffer,
* using a specific polynomium and an initial value.
* The crc is accomplished by reversing the input, the initial value
* and the output (remainder).
*
* @param data: Input data buffer pointer
* @param crc: Initial value of the checksum
* @param size: Number of bytes
*
* @return 32-bit remainder of the checksum
*/
template <uint32_t Poly>
uint32_t
crc32(const uint8_t* data, uint32_t crc, std::size_t size)
{
uint32_t byte = 0;
crc = reverseBits(crc);
for (auto i = 0; i < size; i++) {
byte = data[i];
// 32-bit reverse
byte = reverseBits(byte);
for (auto j = 0; j <= 7; j++) {
if ((int)(crc ^ byte) < 0) {
crc = (crc << 1) ^ Poly;
} else {
crc = crc << 1;
}
byte = byte << 1;
}
}
return reverseBits(crc);
}
#endif // __BASE_CRC_HH__
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