Mercurial > code
view C++/Base64.h @ 242:a9883eeb9757
Add tests for Base64
author | David Demelier <markand@malikania.fr> |
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date | Thu, 11 Sep 2014 21:09:58 +0200 |
parents | b97d75a78e22 |
children | 73e5381d7baf |
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/* * Base64.h -- base64 encoding and decoding * * Copyright (c) 2013, 2014 David Demelier <markand@malikania.fr> * * Permission to use, copy, modify, and/or distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #ifndef _BASE_64_H_ #define _BASE_64_H_ /** * @file Base64.h * @brief Base64 encoding and decoding */ #include <stdexcept> #include <string> /** * @class Base64 * @brief Encode and decode Base64 data */ class Base64 { public: /** * Get the base 64 character from the 6-bits value. * * @param value the value */ static char lookup(int value) noexcept; /** * Get the integer value from the base 64 character. * * @param ch the base64 character */ static int rlookup(char ch); /** * Encode the input to the output. Requirements: * InputIt must be InputIterator * OutputIt must be OutputIterator * * @param input the beginning * @param end the end of the data * @output the output destination */ template <typename InputIt, typename OutputIt> static void encode(InputIt input, InputIt end, OutputIt output) { while (input != end) { char inputbuf[3] = { 0, 0, 0 }; int count; for (count = 0; count < 3 && input != end; ++count) inputbuf[count] = *input++; *output++ = lookup(inputbuf[0] >> 2 & 0x3f); *output++ = lookup((inputbuf[0] << 4 & 0x3f) | (inputbuf[1] >> 4 & 0x0f)); *output++ = (count < 2) ? '=' : lookup((inputbuf[1] << 2 & 0x3c) | (inputbuf[2] >> 6 & 0x03)); *output++ = (count < 3) ? '=' : lookup(inputbuf[2] & 0x3f); } } /** * Decode the input to the output. Requirements: * InputIt must be InputIterator * OutputIt must be OutputIterator * * @param input the beginning * @param end the end of the data * @output the output destination * @throw std::invalid_argument on bad base64 string */ template <typename InputIt, typename OutputIt> static void decode(InputIt input, InputIt end, OutputIt output) { while (input != end) { char inputbuf[4] = { 0, 0, 0, 0 }; int count; for (count = 0; count < 4 && input != end; ++count) { inputbuf[count] = (*input == '=') ? '=' : rlookup(*input); input++; } if (count != 4) throw std::invalid_argument("truncated string"); *output++ = (inputbuf[0] << 2 & 0xfc) | (inputbuf[1] >> 4 & 0x03); if (inputbuf[2] != '=') *output++ = (inputbuf[1] << 4 & 0xf0) | (inputbuf[2] >> 2 & 0x0f); if (inputbuf[3] != '=') *output++ = (inputbuf[2] << 6 & 0xc0) | (inputbuf[3] & 0x3f); } } /** * Encode a string. * * @param input the input string * @return the base64 formatted string */ static std::string encode(const std::string &input); /** * Decode a string. * * @param input the base64 formatted string * @return the original string * @throw std::invalid_argument on bad base64 string */ static std::string decode(const std::string &input); }; #endif // !_BASE_64_H_