| /* |
| * Copyright (c) 2011-2014, Intel Corporation |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without modification, |
| * are permitted provided that the following conditions are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright notice, this |
| * list of conditions and the following disclaimer. |
| * |
| * 2. 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. |
| * |
| * 3. Neither the name of the copyright holder 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 HOLDER 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. |
| */ |
| |
| #pragma once |
| |
| #include <limits> |
| #include <sstream> |
| #include <string> |
| #include <stdint.h> |
| #include <cmath> |
| #include <type_traits> |
| |
| /* details namespace is here to hide implementation details to header end user. It |
| * is NOT intended to be used outside. */ |
| namespace details |
| { |
| |
| /* List of allowed types for conversion */ |
| template <typename T> |
| struct ConvertionAllowed : std::false_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<bool> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<long long> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<unsigned long long> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<long> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<unsigned long> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<int> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<unsigned int> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<short> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<unsigned short> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<unsigned char> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<signed char> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<float> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowed<double> : std::true_type |
| { |
| }; |
| |
| /* Allow chars and unsigned chars to be converted via integers */ |
| template <typename T, typename Via> |
| struct ConvertionAllowedVia : std::false_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowedVia<unsigned char, unsigned int> : std::true_type |
| { |
| }; |
| template <> |
| struct ConvertionAllowedVia<signed char, int> : std::true_type |
| { |
| }; |
| |
| template <typename T> |
| static inline bool convertTo(const std::string &str, T &result) |
| { |
| /* Check that conversion to that type is allowed. |
| * If this fails, this means that this template was not intended to be used |
| * with this type, thus that the result is undefined. */ |
| static_assert(ConvertionAllowed<T>::value, "convertTo does not support this conversion"); |
| |
| if (str.find_first_of(std::string("\r\n\t\v ")) != std::string::npos) { |
| return false; |
| } |
| |
| /* Check for a '-' in string. If type is unsigned and a - is found, the |
| * parsing fails. This is made necessary because "-1" is read as 65535 for |
| * uint16_t, for example */ |
| if (str.find("-") != std::string::npos && !std::numeric_limits<T>::is_signed) { |
| return false; |
| } |
| |
| std::stringstream ss(str); |
| |
| /* Sadly, the stream conversion does not handle hexadecimal format, thus |
| * check is done manually */ |
| if (str.substr(0, 2) == "0x") { |
| if (std::numeric_limits<T>::is_integer) { |
| ss >> std::hex >> result; |
| } else { |
| /* Conversion undefined for non integers */ |
| return false; |
| } |
| } else { |
| ss >> result; |
| } |
| |
| return ss.eof() && !ss.fail() && !ss.bad(); |
| } |
| |
| template <typename T, typename Via> |
| static inline bool convertToVia(const std::string &str, T &result) |
| { |
| /* Check that conversion to that type is allowed. |
| * If this fails, this means that this template was not intended to be used |
| * with this type, thus that the result is undefined. */ |
| static_assert(ConvertionAllowedVia<T, Via>::value, |
| "convertToVia does not support this conversion"); |
| |
| /* We want to override the behaviour of convertTo<T> with that of |
| * convertTo<Via> and then safely cast the result into a T. */ |
| Via res; |
| |
| if (!convertTo<Via>(str, res)) { |
| return false; |
| } |
| |
| if ((res > std::numeric_limits<T>::max()) or (res < std::numeric_limits<T>::min())) { |
| return false; |
| } |
| |
| result = static_cast<T>(res); |
| return true; |
| } |
| } // namespace details |
| |
| /** |
| * Convert a string to a given type. |
| * |
| * This template function read the value of the type T in the given string. |
| * The function does not allow to have white spaces around the value to parse |
| * and tries to parse the whole string, which means that if some bytes were not |
| * read in the string, the function fails. |
| * Hexadecimal representation (ie numbers starting with 0x) is supported only |
| * for integral types conversions. |
| * Result may be modified, even in case of failure. |
| * |
| * @param[in] str the string to parse. |
| * @param[out] result reference to object where to store the result. |
| * |
| * @return true if conversion was successful, false otherwise. |
| */ |
| template <typename T> |
| static inline bool convertTo(const std::string &str, T &result) |
| { |
| return details::convertTo<T>(str, result); |
| } |
| |
| /** Specialization for unsigned char of convertTo template function. |
| * |
| * This function follows the same paradigm than it's generic version. |
| * |
| * The generic version was converting char as it was a character |
| * (unsigned char is an alias to unsigned char on most compiler). |
| * Thus converting "1" would return 49 ie '1'. |
| * As convertTo is thought as an _numerical_ convertion tool |
| * (contrary to boost::lexical_cast for example), |
| * forbid considering the input as a character and consider unsigned char |
| * (aka unsigned char) as a number exclusively. |
| * |
| * @param[in] str the string to parse. |
| * @param[out] result reference to object where to store the result. |
| * |
| * @return true if conversion was successful, false otherwise. |
| */ |
| template <> |
| inline bool convertTo<unsigned char>(const std::string &str, unsigned char &result) |
| { |
| return details::convertToVia<unsigned char, unsigned int>(str, result); |
| } |
| |
| /** Specialization for signed char of convertTo template function. |
| * |
| * @see convertTo<unsigned char> |
| */ |
| template <> |
| inline bool convertTo<signed char>(const std::string &str, signed char &result) |
| { |
| return details::convertToVia<signed char, int>(str, result); |
| } |
| /** |
| * Specialization for float of convertTo template function. |
| * |
| * This function follows the same paradigm than it's generic version and is |
| * based on it but makes furthers checks on the returned value. |
| * |
| * The specific implementation is made necessary because the stlport conversion |
| * from string to float behaves differently than GNU STL: overflow produce |
| * +/-Infinity rather than an error. |
| * |
| * @param[in] str the string to parse. |
| * @param[out] result reference to object where to store the result. |
| * |
| * @return true if conversion was successful, false otherwise. |
| */ |
| template <> |
| inline bool convertTo<float>(const std::string &str, float &result) |
| { |
| if (!details::convertTo(str, result)) { |
| return false; |
| } |
| |
| if (!std::isfinite(result)) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| /** |
| * Specialization for double of convertTo template function. |
| * |
| * This function follows the same paradigm than it's generic version and is |
| * based on it but makes furthers checks on the returned value. |
| * |
| * The specific implementation is made necessary because the stlport conversion |
| * from string to double behaves differently than GNU STL: overflow produce |
| * +/-Infinity rather than an error. |
| * |
| * @param[in] str the string to parse. |
| * @param[out] result reference to object where to store the result. |
| * |
| * @return true if conversion was successful, false otherwise. |
| */ |
| template <> |
| inline bool convertTo<double>(const std::string &str, double &result) |
| { |
| if (!details::convertTo(str, result)) { |
| return false; |
| } |
| |
| if (!std::isfinite(result)) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| /** |
| * Specialization for boolean of convertTo template function. |
| * |
| * This function follows the same paradigm than it's generic version. |
| * This function accepts to parse boolean as "0/1" or "false/true" or |
| * "FALSE/TRUE". |
| * The specific implementation is made necessary because the behaviour of |
| * string streams when parsing boolean values is not sufficient to fit our |
| * requirements. Indeed, parsing "true" will correctly parse the value, but the |
| * end of stream is not reached which makes the ss.eof() fails in the generic |
| * implementation. |
| * |
| * @param[in] str the string to parse. |
| * @param[out] result reference to object where to store the result. |
| * |
| * @return true if conversion was successful, false otherwise. |
| */ |
| template <> |
| inline bool convertTo<bool>(const std::string &str, bool &result) |
| { |
| if (str == "0" || str == "FALSE" || str == "false") { |
| result = false; |
| return true; |
| } |
| |
| if (str == "1" || str == "TRUE" || str == "true") { |
| result = true; |
| return true; |
| } |
| |
| return false; |
| } |