mirror of
https://github.com/dj0abr/SSB_HighSpeed_Modem.git
synced 2024-08-22 06:06:37 -04:00
603 lines
23 KiB
C++
603 lines
23 KiB
C++
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/*
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(**************************************************************************)
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(* *)
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(* Schifra *)
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(* Reed-Solomon Error Correcting Code Library *)
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(* *)
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(* Release Version 0.0.1 *)
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(* http://www.schifra.com *)
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(* Copyright (c) 2000-2020 Arash Partow, All Rights Reserved. *)
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(* *)
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(* The Schifra Reed-Solomon error correcting code library and all its *)
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(* components are supplied under the terms of the General Schifra License *)
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(* agreement. The contents of the Schifra Reed-Solomon error correcting *)
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(* code library and all its components may not be copied or disclosed *)
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(* except in accordance with the terms of that agreement. *)
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(* *)
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(* URL: http://www.schifra.com/license.html *)
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(* *)
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(**************************************************************************)
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*/
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#ifndef INCLUDE_SCHIFRA_ERROR_PROCESSES_HPP
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#define INCLUDE_SCHIFRA_ERROR_PROCESSES_HPP
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#include <cstddef>
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#include <cstdio>
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#include <cstdlib>
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#include <iostream>
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#include <deque>
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#include <vector>
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#include "schifra_reed_solomon_block.hpp"
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#include "schifra_fileio.hpp"
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namespace schifra
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{
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template <std::size_t code_length, std::size_t fec_length>
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inline void add_erasure_error(const std::size_t& position, reed_solomon::block<code_length,fec_length>& block)
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{
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block[position] = (~block[position]) & 0xFF; // Or one can simply equate to zero
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline void add_error(const std::size_t& position, reed_solomon::block<code_length,fec_length>& block)
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{
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block[position] = (~block[position]) & 0xFF;
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline void add_error_4bit_symbol(const std::size_t& position, reed_solomon::block<code_length,fec_length>& block)
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{
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block[position] = (~block[position]) & 0x0F;
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline void corrupt_message_all_errors00(reed_solomon::block<code_length,fec_length>& rsblock,
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const std::size_t& start_position,
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const std::size_t& scale = 1)
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{
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for (std::size_t i = 0; i < (fec_length >> 1); ++i)
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{
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add_error((start_position + scale * i) % code_length,rsblock);
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}
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline void corrupt_message_all_errors_wth_mask(reed_solomon::block<code_length,fec_length>& rsblock,
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const std::size_t& start_position,
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const int& mask,
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const std::size_t& scale = 1)
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{
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for (std::size_t i = 0; i < (fec_length >> 1); ++i)
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{
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std::size_t position = (start_position + scale * i) % code_length;
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rsblock[position] = (~rsblock[position]) & mask;
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}
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline void corrupt_message_all_errors(schifra::reed_solomon::block<code_length,fec_length>& rsblock,
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const std::size_t error_count,
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const std::size_t& start_position,
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const std::size_t& scale = 1)
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{
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for (std::size_t i = 0; i < error_count; ++i)
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{
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add_error((start_position + scale * i) % code_length,rsblock);
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}
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline void corrupt_message_all_erasures00(reed_solomon::block<code_length,fec_length>& rsblock,
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reed_solomon::erasure_locations_t& erasure_list,
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const std::size_t& start_position,
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const std::size_t& scale = 1)
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{
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std::size_t erasures[code_length];
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for (std::size_t i = 0; i < code_length; ++i) erasures[i] = 0;
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for (std::size_t i = 0; i < fec_length; ++i)
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{
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std::size_t error_position = (start_position + scale * i) % code_length;
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add_erasure_error(error_position,rsblock);
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erasures[error_position] = 1;
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}
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for (std::size_t i = 0; i < code_length; ++i)
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{
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if (erasures[i] == 1) erasure_list.push_back(i);
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}
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline void corrupt_message_all_erasures(reed_solomon::block<code_length,fec_length>& rsblock,
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reed_solomon::erasure_locations_t& erasure_list,
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const std::size_t erasure_count,
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const std::size_t& start_position,
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const std::size_t& scale = 1)
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{
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std::size_t erasures[code_length];
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for (std::size_t i = 0; i < code_length; ++i) erasures[i] = 0;
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for (std::size_t i = 0; i < erasure_count; ++i)
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{
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/* Note: Must make sure duplicate erasures are not added */
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std::size_t error_position = (start_position + scale * i) % code_length;
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add_erasure_error(error_position,rsblock);
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erasures[error_position] = 1;
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}
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for (std::size_t i = 0; i < code_length; ++i)
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{
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if (erasures[i] == 1) erasure_list.push_back(i);
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}
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}
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namespace error_mode
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{
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enum type
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{
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errors_erasures, // Errors first then erasures
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erasures_errors // Erasures first then errors
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};
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline void corrupt_message_errors_erasures(reed_solomon::block<code_length,fec_length>& rsblock,
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const error_mode::type& mode,
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const std::size_t& start_position,
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const std::size_t& erasure_count,
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reed_solomon::erasure_locations_t& erasure_list,
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const std::size_t between_space = 0)
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{
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std::size_t error_count = (fec_length - erasure_count) >> 1;
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if ((2 * error_count) + erasure_count > fec_length)
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{
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std::cout << "corrupt_message_errors_erasures() - ERROR Too many erasures and errors!" << std::endl;
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std::cout << "Error Count: " << error_count << std::endl;
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std::cout << "Erasure Count: " << error_count << std::endl;
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return;
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}
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std::size_t erasures[code_length];
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for (std::size_t i = 0; i < code_length; ++i) erasures[i] = 0;
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std::size_t error_position = 0;
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switch (mode)
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{
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case error_mode::erasures_errors : {
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for (std::size_t i = 0; i < erasure_count; ++i)
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{
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error_position = (start_position + i) % code_length;
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add_erasure_error(error_position,rsblock);
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erasures[error_position] = 1;
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}
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for (std::size_t i = 0; i < error_count; ++i)
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{
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error_position = (start_position + erasure_count + between_space + i) % code_length;
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add_error(error_position,rsblock);
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}
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}
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break;
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case error_mode::errors_erasures : {
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for (std::size_t i = 0; i < error_count; ++i)
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{
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error_position = (start_position + i) % code_length;
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add_error(error_position,rsblock);
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}
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for (std::size_t i = 0; i < erasure_count; ++i)
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{
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error_position = (start_position + error_count + between_space + i) % code_length;
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add_erasure_error(error_position,rsblock);
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erasures[error_position] = 1;
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}
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}
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break;
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}
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for (std::size_t i = 0; i < code_length; ++i)
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{
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if (erasures[i] == 1) erasure_list.push_back(i);
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}
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline void corrupt_message_interleaved_errors_erasures(reed_solomon::block<code_length,fec_length>& rsblock,
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const std::size_t& start_position,
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const std::size_t& erasure_count,
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reed_solomon::erasure_locations_t& erasure_list)
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{
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std::size_t error_count = (fec_length - erasure_count) >> 1;
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if ((2 * error_count) + erasure_count > fec_length)
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{
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std::cout << "corrupt_message_interleaved_errors_erasures() - [1] ERROR Too many erasures and errors!" << std::endl;
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std::cout << "Error Count: " << error_count << std::endl;
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std::cout << "Erasure Count: " << error_count << std::endl;
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return;
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}
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std::size_t erasures[code_length];
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for (std::size_t i = 0; i < code_length; ++i) erasures[i] = 0;
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std::size_t e = 0;
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std::size_t s = 0;
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std::size_t i = 0;
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while ((e < error_count) || (s < erasure_count) || (i < (error_count + erasure_count)))
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{
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std::size_t error_position = (start_position + i) % code_length;
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if (((i & 0x01) == 0) && (s < erasure_count))
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{
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add_erasure_error(error_position,rsblock);
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erasures[error_position] = 1;
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s++;
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}
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else if (((i & 0x01) == 1) && (e < error_count))
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{
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e++;
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add_error(error_position,rsblock);
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}
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++i;
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}
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for (std::size_t j = 0; j < code_length; ++j)
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{
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if (erasures[j] == 1) erasure_list.push_back(j);
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}
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if ((2 * e) + erasure_list.size() > fec_length)
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{
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std::cout << "corrupt_message_interleaved_errors_erasures() - [2] ERROR Too many erasures and errors!" << std::endl;
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std::cout << "Error Count: " << error_count << std::endl;
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std::cout << "Erasure Count: " << error_count << std::endl;
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return;
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}
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}
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namespace details
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{
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template <std::size_t code_length, std::size_t fec_length, bool t>
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struct corrupt_message_all_errors_segmented_impl
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{
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static void process(reed_solomon::block<code_length,fec_length>& rsblock,
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const std::size_t& start_position,
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const std::size_t& distance_between_blocks = 1)
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{
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std::size_t block_1_error_count = (fec_length >> 2);
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std::size_t block_2_error_count = (fec_length >> 1) - block_1_error_count;
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for (std::size_t i = 0; i < block_1_error_count; ++i)
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{
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add_error((start_position + i) % code_length,rsblock);
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}
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std::size_t new_start_position = (start_position + (block_1_error_count)) + distance_between_blocks;
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for (std::size_t i = 0; i < block_2_error_count; ++i)
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{
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add_error((new_start_position + i) % code_length,rsblock);
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}
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}
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};
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template <std::size_t code_length, std::size_t fec_length>
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struct corrupt_message_all_errors_segmented_impl<code_length,fec_length,false>
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{
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static void process(reed_solomon::block<code_length,fec_length>&,
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const std::size_t&, const std::size_t&)
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{}
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};
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline void corrupt_message_all_errors_segmented(reed_solomon::block<code_length,fec_length>& rsblock,
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const std::size_t& start_position,
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const std::size_t& distance_between_blocks = 1)
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{
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details::corrupt_message_all_errors_segmented_impl<code_length,fec_length,(fec_length > 2)>::
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process(rsblock,start_position,distance_between_blocks);
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}
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inline bool check_for_duplicate_erasures(const std::vector<int>& erasure_list)
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{
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for (std::size_t i = 0; i < erasure_list.size(); ++i)
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{
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for (std::size_t j = i + 1; j < erasure_list.size(); ++j)
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{
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if (erasure_list[i] == erasure_list[j])
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{
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return false;
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}
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}
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}
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return true;
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}
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inline void dump_erasure_list(const schifra::reed_solomon::erasure_locations_t& erasure_list)
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{
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for (std::size_t i = 0; i < erasure_list.size(); ++i)
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{
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std::cout << "[" << i << "," << erasure_list[i] << "] ";
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}
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std::cout << std::endl;
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline bool is_block_equivelent(const reed_solomon::block<code_length,fec_length>& rsblock,
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const std::string& data,
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const bool display = false,
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const bool all_errors = false)
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{
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std::string::const_iterator it = data.begin();
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bool error_found = false;
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for (std::size_t i = 0; i < code_length - fec_length; ++i, ++it)
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{
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if (static_cast<char>(rsblock.data[i] & 0xFF) != (*it))
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{
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error_found = true;
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if (display)
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{
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printf("is_block_equivelent() - Error at loc : %02d\td1: %02X\td2: %02X\n",
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static_cast<unsigned int>(i),
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rsblock.data[i],
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static_cast<unsigned char>(*it));
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}
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if (!all_errors)
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return false;
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}
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}
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return !error_found;
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}
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template <std::size_t code_length, std::size_t fec_length>
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inline bool are_blocks_equivelent(const reed_solomon::block<code_length,fec_length>& block1,
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const reed_solomon::block<code_length,fec_length>& block2,
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const std::size_t span = code_length,
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const bool display = false,
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const bool all_errors = false)
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{
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bool error_found = false;
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for (std::size_t i = 0; i < span; ++i)
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{
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if (block1[i] != block2[i])
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{
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error_found = true;
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if (display)
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{
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printf("are_blocks_equivelent() - Error at loc : %02d\td1: %04X\td2: %04X\n",
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static_cast<unsigned int>(i),
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block1[i],
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block2[i]);
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}
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if (!all_errors)
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return false;
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}
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}
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return !error_found;
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}
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template <std::size_t code_length, std::size_t fec_length, std::size_t stack_size>
|
||
|
inline bool block_stacks_equivelent(const reed_solomon::block<code_length,fec_length> block_stack1[stack_size],
|
||
|
const reed_solomon::block<code_length,fec_length> block_stack2[stack_size])
|
||
|
{
|
||
|
for (std::size_t i = 0; i < stack_size; ++i)
|
||
|
{
|
||
|
if (!are_blocks_equivelent(block_stack1[i],block_stack2[i]))
|
||
|
{
|
||
|
return false;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return true;
|
||
|
}
|
||
|
|
||
|
template <std::size_t block_length, std::size_t stack_size>
|
||
|
inline bool block_stacks_equivelent(const reed_solomon::data_block<std::size_t,block_length> block_stack1[stack_size],
|
||
|
const reed_solomon::data_block<std::size_t,block_length> block_stack2[stack_size])
|
||
|
{
|
||
|
for (std::size_t i = 0; i < stack_size; ++i)
|
||
|
{
|
||
|
for (std::size_t j = 0; j < block_length; ++j)
|
||
|
{
|
||
|
if (block_stack1[i][j] != block_stack2[i][j])
|
||
|
{
|
||
|
return false;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return true;
|
||
|
}
|
||
|
|
||
|
inline void corrupt_file_with_burst_errors(const std::string& file_name,
|
||
|
const long& start_position,
|
||
|
const long& burst_length)
|
||
|
{
|
||
|
if (!schifra::fileio::file_exists(file_name))
|
||
|
{
|
||
|
std::cout << "corrupt_file() - Error: " << file_name << " does not exist!" << std::endl;
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
if (static_cast<std::size_t>(start_position + burst_length) >= schifra::fileio::file_size(file_name))
|
||
|
{
|
||
|
std::cout << "corrupt_file() - Error: Burst error out of bounds." << std::endl;
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
std::vector<char> data(burst_length);
|
||
|
|
||
|
std::ifstream ifile(file_name.c_str(), std::ios::in | std::ios::binary);
|
||
|
|
||
|
if (!ifile)
|
||
|
{
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
ifile.seekg(start_position,std::ios_base::beg);
|
||
|
ifile.read(&data[0],burst_length);
|
||
|
ifile.close();
|
||
|
|
||
|
for (long i = 0; i < burst_length; ++i)
|
||
|
{
|
||
|
data[i] = ~data[i];
|
||
|
}
|
||
|
|
||
|
std::ofstream ofile(file_name.c_str(), std::ios::in | std::ios::out | std::ios::binary);
|
||
|
|
||
|
if (!ofile)
|
||
|
{
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
ofile.seekp(start_position,std::ios_base::beg);
|
||
|
ofile.write(&data[0],burst_length);
|
||
|
ofile.close();
|
||
|
}
|
||
|
|
||
|
static const std::size_t global_random_error_index[] =
|
||
|
{
|
||
|
13, 170, 148, 66, 228, 208, 182, 92,
|
||
|
4, 137, 97, 99, 237, 151, 15, 0,
|
||
|
119, 243, 41, 222, 33, 211, 188, 5,
|
||
|
44, 30, 210, 111, 54, 79, 61, 223,
|
||
|
239, 149, 73, 115, 201, 234, 194, 62,
|
||
|
147, 70, 19, 49, 72, 52, 164, 29,
|
||
|
102, 225, 203, 153, 18, 205, 40, 217,
|
||
|
165, 177, 166, 134, 236, 68, 231, 154,
|
||
|
116, 136, 47, 240, 46, 89, 120, 183,
|
||
|
242, 28, 161, 226, 241, 230, 10, 131,
|
||
|
207, 132, 83, 171, 202, 195, 227, 206,
|
||
|
112, 88, 90, 146, 117, 180, 26, 78,
|
||
|
118, 254, 107, 110, 220, 7, 192, 187,
|
||
|
31, 175, 127, 209, 32, 12, 84, 128,
|
||
|
190, 156, 95, 105, 104, 246, 91, 215,
|
||
|
219, 142, 36, 186, 247, 233, 167, 133,
|
||
|
160, 16, 140, 169, 23, 96, 155, 235,
|
||
|
179, 76, 253, 103, 238, 67, 35, 121,
|
||
|
100, 27, 213, 58, 77, 248, 174, 39,
|
||
|
214, 56, 42, 200, 106, 21, 129, 114,
|
||
|
252, 113, 168, 53, 25, 216, 64, 232,
|
||
|
81, 75, 2, 224, 250, 60, 135, 204,
|
||
|
48, 196, 94, 63, 244, 191, 93, 126,
|
||
|
138, 159, 9, 85, 249, 34, 185, 163,
|
||
|
17, 65, 184, 82, 109, 172, 108, 69,
|
||
|
150, 3, 20, 221, 162, 212, 152, 59,
|
||
|
198, 74, 229, 55, 87, 178, 141, 199,
|
||
|
57, 130, 80, 173, 101, 122, 144, 51,
|
||
|
139, 11, 8, 125, 158, 124, 123, 37,
|
||
|
14, 24, 22, 43, 197, 50, 98, 6,
|
||
|
176, 251, 86, 218, 193, 71, 145, 1,
|
||
|
45, 38, 189, 143, 245, 157, 181
|
||
|
};
|
||
|
|
||
|
static const std::size_t error_index_size = sizeof(global_random_error_index) / sizeof(std::size_t);
|
||
|
|
||
|
template <std::size_t code_length, std::size_t fec_length>
|
||
|
inline void corrupt_message_all_errors_at_index(schifra::reed_solomon::block<code_length,fec_length>& rsblock,
|
||
|
const std::size_t error_count,
|
||
|
const std::size_t& error_index_start_position,
|
||
|
const bool display_positions = false)
|
||
|
{
|
||
|
schifra::reed_solomon::block<code_length,fec_length> tmp_rsblock = rsblock;
|
||
|
|
||
|
for (std::size_t i = 0; i < error_count; ++i)
|
||
|
{
|
||
|
std::size_t error_position = (global_random_error_index[(error_index_start_position + i) % error_index_size]) % code_length;
|
||
|
|
||
|
add_error(error_position,rsblock);
|
||
|
|
||
|
if (display_positions)
|
||
|
{
|
||
|
std::cout << "Error index: " << error_position << std::endl;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
template <std::size_t code_length, std::size_t fec_length>
|
||
|
inline void corrupt_message_all_errors_at_index(schifra::reed_solomon::block<code_length,fec_length>& rsblock,
|
||
|
const std::size_t error_count,
|
||
|
const std::size_t& error_index_start_position,
|
||
|
const std::vector<std::size_t>& random_error_index,
|
||
|
const bool display_positions = false)
|
||
|
{
|
||
|
for (std::size_t i = 0; i < error_count; ++i)
|
||
|
{
|
||
|
std::size_t error_position = (random_error_index[(error_index_start_position + i) % random_error_index.size()]) % code_length;
|
||
|
|
||
|
add_error(error_position,rsblock);
|
||
|
|
||
|
if (display_positions)
|
||
|
{
|
||
|
std::cout << "Error index: " << error_position << std::endl;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
inline void generate_error_index(const std::size_t index_size,
|
||
|
std::vector<std::size_t>& random_error_index,
|
||
|
std::size_t seed)
|
||
|
{
|
||
|
if (0 == seed)
|
||
|
{
|
||
|
seed = 0xA5A5A5A5;
|
||
|
}
|
||
|
|
||
|
::srand(static_cast<unsigned int>(seed));
|
||
|
|
||
|
std::deque<std::size_t> index_list;
|
||
|
|
||
|
for (std::size_t i = 0; i < index_size; ++i)
|
||
|
{
|
||
|
index_list.push_back(i);
|
||
|
}
|
||
|
|
||
|
random_error_index.reserve(index_size);
|
||
|
random_error_index.resize(0);
|
||
|
|
||
|
while (!index_list.empty())
|
||
|
{
|
||
|
// possibly the worst way of doing this.
|
||
|
std::size_t index = ::rand() % index_list.size();
|
||
|
|
||
|
random_error_index.push_back(index_list[index]);
|
||
|
index_list.erase(index_list.begin() + index);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
} // namespace schifra
|
||
|
|
||
|
#endif
|