1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef BASE_STRINGS_STRING_NUMBER_CONVERSIONS_H_ 6 #define BASE_STRINGS_STRING_NUMBER_CONVERSIONS_H_ 7 8 #include <stddef.h> 9 #include <stdint.h> 10 11 #include <string> 12 #include <vector> 13 14 #include "base/base_export.h" 15 #include "base/strings/string16.h" 16 #include "base/strings/string_piece.h" 17 18 // ---------------------------------------------------------------------------- 19 // IMPORTANT MESSAGE FROM YOUR SPONSOR 20 // 21 // This file contains no "wstring" variants. New code should use string16. If 22 // you need to make old code work, use the UTF8 version and convert. Please do 23 // not add wstring variants. 24 // 25 // Please do not add "convenience" functions for converting strings to integers 26 // that return the value and ignore success/failure. That encourages people to 27 // write code that doesn't properly handle the error conditions. 28 // ---------------------------------------------------------------------------- 29 30 namespace base { 31 32 // Number -> string conversions ------------------------------------------------ 33 34 BASE_EXPORT std::string IntToString(int value); 35 BASE_EXPORT string16 IntToString16(int value); 36 37 BASE_EXPORT std::string UintToString(unsigned value); 38 BASE_EXPORT string16 UintToString16(unsigned value); 39 40 BASE_EXPORT std::string Int64ToString(int64_t value); 41 BASE_EXPORT string16 Int64ToString16(int64_t value); 42 43 BASE_EXPORT std::string Uint64ToString(uint64_t value); 44 BASE_EXPORT string16 Uint64ToString16(uint64_t value); 45 46 BASE_EXPORT std::string SizeTToString(size_t value); 47 BASE_EXPORT string16 SizeTToString16(size_t value); 48 49 // Deprecated: prefer std::to_string(double) instead. 50 // DoubleToString converts the double to a string format that ignores the 51 // locale. If you want to use locale specific formatting, use ICU. 52 BASE_EXPORT std::string DoubleToString(double value); 53 54 // String -> number conversions ------------------------------------------------ 55 56 // Perform a best-effort conversion of the input string to a numeric type, 57 // setting |*output| to the result of the conversion. Returns true for 58 // "perfect" conversions; returns false in the following cases: 59 // - Overflow. |*output| will be set to the maximum value supported 60 // by the data type. 61 // - Underflow. |*output| will be set to the minimum value supported 62 // by the data type. 63 // - Trailing characters in the string after parsing the number. |*output| 64 // will be set to the value of the number that was parsed. 65 // - Leading whitespace in the string before parsing the number. |*output| will 66 // be set to the value of the number that was parsed. 67 // - No characters parseable as a number at the beginning of the string. 68 // |*output| will be set to 0. 69 // - Empty string. |*output| will be set to 0. 70 // WARNING: Will write to |output| even when returning false. 71 // Read the comments above carefully. 72 BASE_EXPORT bool StringToInt(const StringPiece& input, int* output); 73 BASE_EXPORT bool StringToInt(const StringPiece16& input, int* output); 74 75 BASE_EXPORT bool StringToUint(const StringPiece& input, unsigned* output); 76 BASE_EXPORT bool StringToUint(const StringPiece16& input, unsigned* output); 77 78 BASE_EXPORT bool StringToInt64(const StringPiece& input, int64_t* output); 79 BASE_EXPORT bool StringToInt64(const StringPiece16& input, int64_t* output); 80 81 BASE_EXPORT bool StringToUint64(const StringPiece& input, uint64_t* output); 82 BASE_EXPORT bool StringToUint64(const StringPiece16& input, uint64_t* output); 83 84 BASE_EXPORT bool StringToSizeT(const StringPiece& input, size_t* output); 85 BASE_EXPORT bool StringToSizeT(const StringPiece16& input, size_t* output); 86 87 // Deprecated: prefer std::stod() instead. 88 // For floating-point conversions, only conversions of input strings in decimal 89 // form are defined to work. Behavior with strings representing floating-point 90 // numbers in hexadecimal, and strings representing non-finite values (such as 91 // NaN and inf) is undefined. Otherwise, these behave the same as the integral 92 // variants. This expects the input string to NOT be specific to the locale. 93 // If your input is locale specific, use ICU to read the number. 94 // WARNING: Will write to |output| even when returning false. 95 // Read the comments here and above StringToInt() carefully. 96 BASE_EXPORT bool StringToDouble(const std::string& input, double* output); 97 98 // Hex encoding ---------------------------------------------------------------- 99 100 // Returns a hex string representation of a binary buffer. The returned hex 101 // string will be in upper case. This function does not check if |size| is 102 // within reasonable limits since it's written with trusted data in mind. If 103 // you suspect that the data you want to format might be large, the absolute 104 // max size for |size| should be is 105 // std::numeric_limits<size_t>::max() / 2 106 BASE_EXPORT std::string HexEncode(const void* bytes, size_t size); 107 108 // Best effort conversion, see StringToInt above for restrictions. 109 // Will only successful parse hex values that will fit into |output|, i.e. 110 // -0x80000000 < |input| < 0x7FFFFFFF. 111 BASE_EXPORT bool HexStringToInt(const StringPiece& input, int* output); 112 113 // Best effort conversion, see StringToInt above for restrictions. 114 // Will only successful parse hex values that will fit into |output|, i.e. 115 // 0x00000000 < |input| < 0xFFFFFFFF. 116 // The string is not required to start with 0x. 117 BASE_EXPORT bool HexStringToUInt(const StringPiece& input, uint32_t* output); 118 119 // Best effort conversion, see StringToInt above for restrictions. 120 // Will only successful parse hex values that will fit into |output|, i.e. 121 // -0x8000000000000000 < |input| < 0x7FFFFFFFFFFFFFFF. 122 BASE_EXPORT bool HexStringToInt64(const StringPiece& input, int64_t* output); 123 124 // Best effort conversion, see StringToInt above for restrictions. 125 // Will only successful parse hex values that will fit into |output|, i.e. 126 // 0x0000000000000000 < |input| < 0xFFFFFFFFFFFFFFFF. 127 // The string is not required to start with 0x. 128 BASE_EXPORT bool HexStringToUInt64(const StringPiece& input, uint64_t* output); 129 130 // Similar to the previous functions, except that output is a vector of bytes. 131 // |*output| will contain as many bytes as were successfully parsed prior to the 132 // error. There is no overflow, but input.size() must be evenly divisible by 2. 133 // Leading 0x or +/- are not allowed. 134 BASE_EXPORT bool HexStringToBytes(const std::string& input, 135 std::vector<uint8_t>* output); 136 137 } // namespace base 138 139 #endif // BASE_STRINGS_STRING_NUMBER_CONVERSIONS_H_ 140