diff options
Diffstat (limited to 'src/base')
-rw-r--r-- | src/base/crc.hh | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/src/base/crc.hh b/src/base/crc.hh new file mode 100644 index 000000000..132a15c13 --- /dev/null +++ b/src/base/crc.hh @@ -0,0 +1,81 @@ +/* + * 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__ |