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 // DO NOT use these functions in any UI unless it's NOT localized on purpose. 30 // Instead, use base::MessageFormatter for a complex message with numbers 31 // (integer, float, double) embedded or base::Format{Number,Double,Percent} to 32 // just format a single number/percent. Note that some languages use native 33 // digits instead of ASCII digits while others use a group separator or decimal 34 // point different from ',' and '.'. Using these functions in the UI would lead 35 // numbers to be formatted in a non-native way. 36 // ---------------------------------------------------------------------------- 37 38 namespace base { 39 40 // Number -> string conversions ------------------------------------------------ 41 42 BASE_EXPORT std::string IntToString(int value); 43 BASE_EXPORT string16 IntToString16(int value); 44 45 BASE_EXPORT std::string UintToString(unsigned value); 46 BASE_EXPORT string16 UintToString16(unsigned value); 47 48 BASE_EXPORT std::string Int64ToString(int64_t value); 49 BASE_EXPORT string16 Int64ToString16(int64_t value); 50 51 BASE_EXPORT std::string Uint64ToString(uint64_t value); 52 BASE_EXPORT string16 Uint64ToString16(uint64_t value); 53 54 BASE_EXPORT std::string SizeTToString(size_t value); 55 BASE_EXPORT string16 SizeTToString16(size_t value); 56 57 // Deprecated: prefer std::to_string(double) instead. 58 // DoubleToString converts the double to a string format that ignores the 59 // locale. If you want to use locale specific formatting, use ICU. 60 BASE_EXPORT std::string DoubleToString(double value); 61 62 // String -> number conversions ------------------------------------------------ 63 64 // Perform a best-effort conversion of the input string to a numeric type, 65 // setting |*output| to the result of the conversion. Returns true for 66 // "perfect" conversions; returns false in the following cases: 67 // - Overflow. |*output| will be set to the maximum value supported 68 // by the data type. 69 // - Underflow. |*output| will be set to the minimum value supported 70 // by the data type. 71 // - Trailing characters in the string after parsing the number. |*output| 72 // will be set to the value of the number that was parsed. 73 // - Leading whitespace in the string before parsing the number. |*output| will 74 // be set to the value of the number that was parsed. 75 // - No characters parseable as a number at the beginning of the string. 76 // |*output| will be set to 0. 77 // - Empty string. |*output| will be set to 0. 78 // WARNING: Will write to |output| even when returning false. 79 // Read the comments above carefully. 80 BASE_EXPORT bool StringToInt(const StringPiece& input, int* output); 81 BASE_EXPORT bool StringToInt(const StringPiece16& input, int* output); 82 83 BASE_EXPORT bool StringToUint(const StringPiece& input, unsigned* output); 84 BASE_EXPORT bool StringToUint(const StringPiece16& input, unsigned* output); 85 86 BASE_EXPORT bool StringToInt64(const StringPiece& input, int64_t* output); 87 BASE_EXPORT bool StringToInt64(const StringPiece16& input, int64_t* output); 88 89 BASE_EXPORT bool StringToUint64(const StringPiece& input, uint64_t* output); 90 BASE_EXPORT bool StringToUint64(const StringPiece16& input, uint64_t* output); 91 92 BASE_EXPORT bool StringToSizeT(const StringPiece& input, size_t* output); 93 BASE_EXPORT bool StringToSizeT(const StringPiece16& input, size_t* output); 94 95 // Deprecated: prefer std::stod() instead. 96 // For floating-point conversions, only conversions of input strings in decimal 97 // form are defined to work. Behavior with strings representing floating-point 98 // numbers in hexadecimal, and strings representing non-finite values (such as 99 // NaN and inf) is undefined. Otherwise, these behave the same as the integral 100 // variants. This expects the input string to NOT be specific to the locale. 101 // If your input is locale specific, use ICU to read the number. 102 // WARNING: Will write to |output| even when returning false. 103 // Read the comments here and above StringToInt() carefully. 104 BASE_EXPORT bool StringToDouble(const std::string& input, double* output); 105 106 // Hex encoding ---------------------------------------------------------------- 107 108 // Returns a hex string representation of a binary buffer. The returned hex 109 // string will be in upper case. This function does not check if |size| is 110 // within reasonable limits since it's written with trusted data in mind. If 111 // you suspect that the data you want to format might be large, the absolute 112 // max size for |size| should be is 113 // std::numeric_limits<size_t>::max() / 2 114 BASE_EXPORT std::string HexEncode(const void* bytes, size_t size); 115 116 // Best effort conversion, see StringToInt above for restrictions. 117 // Will only successful parse hex values that will fit into |output|, i.e. 118 // -0x80000000 < |input| < 0x7FFFFFFF. 119 BASE_EXPORT bool HexStringToInt(const StringPiece& input, int* output); 120 121 // Best effort conversion, see StringToInt above for restrictions. 122 // Will only successful parse hex values that will fit into |output|, i.e. 123 // 0x00000000 < |input| < 0xFFFFFFFF. 124 // The string is not required to start with 0x. 125 BASE_EXPORT bool HexStringToUInt(const StringPiece& input, uint32_t* output); 126 127 // Best effort conversion, see StringToInt above for restrictions. 128 // Will only successful parse hex values that will fit into |output|, i.e. 129 // -0x8000000000000000 < |input| < 0x7FFFFFFFFFFFFFFF. 130 BASE_EXPORT bool HexStringToInt64(const StringPiece& input, int64_t* output); 131 132 // Best effort conversion, see StringToInt above for restrictions. 133 // Will only successful parse hex values that will fit into |output|, i.e. 134 // 0x0000000000000000 < |input| < 0xFFFFFFFFFFFFFFFF. 135 // The string is not required to start with 0x. 136 BASE_EXPORT bool HexStringToUInt64(const StringPiece& input, uint64_t* output); 137 138 // Similar to the previous functions, except that output is a vector of bytes. 139 // |*output| will contain as many bytes as were successfully parsed prior to the 140 // error. There is no overflow, but input.size() must be evenly divisible by 2. 141 // Leading 0x or +/- are not allowed. 142 BASE_EXPORT bool HexStringToBytes(const std::string& input, 143 std::vector<uint8_t>* output); 144 145 } // namespace base 146 147 #endif // BASE_STRINGS_STRING_NUMBER_CONVERSIONS_H_ 148
