mirror of https://github.com/status-im/leopard.git
94 lines
3.1 KiB
C++
94 lines
3.1 KiB
C++
/*
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Copyright (c) 2017 Christopher A. Taylor. All rights reserved.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
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* Redistributions of source code must retain the above copyright notice,
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this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above copyright notice,
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this list of conditions and the following disclaimer in the documentation
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and/or other materials provided with the distribution.
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* Neither the name of Leopard-RS nor the names of its contributors may be
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used to endorse or promote products derived from this software without
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specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
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LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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POSSIBILITY OF SUCH DAMAGE.
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*/
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#pragma once
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#include "LeopardCommon.h"
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#ifdef LEO_HAS_FF16
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/*
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16-bit Finite Field Math
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This finite field contains 65536 elements and so each element is one byte.
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This library is designed for data that is a multiple of 64 bytes in size.
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Algorithms are described in LeopardCommon.h
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*/
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namespace leopard { namespace ff16 {
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//------------------------------------------------------------------------------
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// Datatypes and Constants
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// Finite field element type
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typedef uint16_t ffe_t;
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// Number of bits per element
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static const unsigned kBits = 16;
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// Finite field order: Number of elements in the field
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static const unsigned kOrder = 65536;
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// Modulus for field operations
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static const ffe_t kModulus = 65535;
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// LFSR Polynomial that generates the field elements
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static const unsigned kPolynomial = 0x1002D;
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//------------------------------------------------------------------------------
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// API
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// Returns false if the self-test fails
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bool Initialize();
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void ReedSolomonEncode(
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uint64_t buffer_bytes,
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unsigned original_count,
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unsigned recovery_count,
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unsigned m, // = NextPow2(recovery_count)
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const void* const * const data,
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void** work); // m * 2 elements
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void ReedSolomonDecode(
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uint64_t buffer_bytes,
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unsigned original_count,
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unsigned recovery_count,
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unsigned m, // = NextPow2(recovery_count)
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unsigned n, // = NextPow2(m + original_count)
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const void* const * const original, // original_count elements
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const void* const * const recovery, // recovery_count elements
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void** work); // n elements
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}} // namespace leopard::ff16
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#endif // LEO_HAS_FF16
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