1 // Copyright 2014 The Chromium OS 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 LIBBRILLO_BRILLO_STRINGS_STRING_UTILS_H_ 6 #define LIBBRILLO_BRILLO_STRINGS_STRING_UTILS_H_ 7 8 #include <string> 9 #include <utility> 10 #include <vector> 11 12 #include <brillo/brillo_export.h> 13 14 namespace brillo { 15 namespace string_utils { 16 17 // Treats the string as a delimited list of substrings and returns the array 18 // of original elements of the list. 19 // |trim_whitespaces| causes each element to have all whitespaces trimmed off. 20 // |purge_empty_strings| specifies whether empty elements from the original 21 // string should be omitted. 22 BRILLO_EXPORT std::vector<std::string> Split(const std::string& str, 23 const std::string& delimiter, 24 bool trim_whitespaces, 25 bool purge_empty_strings); 26 // Splits the string, trims all whitespaces, omits empty string parts. 27 inline std::vector<std::string> Split(const std::string& str, 28 const std::string& delimiter) { 29 return Split(str, delimiter, true, true); 30 } 31 // Splits the string, omits empty string parts. 32 inline std::vector<std::string> Split(const std::string& str, 33 const std::string& delimiter, 34 bool trim_whitespaces) { 35 return Split(str, delimiter, trim_whitespaces, true); 36 } 37 38 // Splits the string into two pieces at the first position of the specified 39 // delimiter. 40 BRILLO_EXPORT std::pair<std::string, std::string> SplitAtFirst( 41 const std::string& str, 42 const std::string& delimiter, 43 bool trim_whitespaces); 44 // Splits the string into two pieces at the first position of the specified 45 // delimiter. Both parts have all whitespaces trimmed off. 46 inline std::pair<std::string, std::string> SplitAtFirst( 47 const std::string& str, 48 const std::string& delimiter) { 49 return SplitAtFirst(str, delimiter, true); 50 } 51 52 // The following overload returns false if the delimiter was not found in the 53 // source string. In this case, |left_part| will be set to |str| and 54 // |right_part| will be empty. 55 BRILLO_EXPORT bool SplitAtFirst(const std::string& str, 56 const std::string& delimiter, 57 std::string* left_part, 58 std::string* right_part, 59 bool trim_whitespaces); 60 // Always trims the white spaces in the split parts. 61 inline bool SplitAtFirst(const std::string& str, 62 const std::string& delimiter, 63 std::string* left_part, 64 std::string* right_part) { 65 return SplitAtFirst(str, delimiter, left_part, right_part, true); 66 } 67 68 // Joins strings into a single string separated by |delimiter|. 69 template <class InputIterator> 70 std::string JoinRange(const std::string& delimiter, 71 InputIterator first, 72 InputIterator last) { 73 std::string result; 74 if (first == last) 75 return result; 76 result = *first; 77 for (++first; first != last; ++first) { 78 result += delimiter; 79 result += *first; 80 } 81 return result; 82 } 83 84 template <class Container> 85 std::string Join(const std::string& delimiter, const Container& strings) { 86 using std::begin; 87 using std::end; 88 return JoinRange(delimiter, begin(strings), end(strings)); 89 } 90 91 inline std::string Join(const std::string& delimiter, 92 std::initializer_list<std::string> strings) { 93 return JoinRange(delimiter, strings.begin(), strings.end()); 94 } 95 96 inline std::string Join(const std::string& delimiter, 97 const std::string& str1, 98 const std::string& str2) { 99 return str1 + delimiter + str2; 100 } 101 102 // string_utils::ToString() is a helper function to convert any scalar type 103 // to a string. In most cases, it redirects the call to std::to_string with 104 // two exceptions: for std::string itself and for double and bool. 105 template <typename T> 106 inline std::string ToString(T value) { 107 return std::to_string(value); 108 } 109 // Having the following overload is handy for templates where the type 110 // of template parameter isn't known and could be a string itself. 111 inline std::string ToString(std::string value) { 112 return value; 113 } 114 // We overload this for double because std::to_string(double) uses %f to 115 // format the value and I would like to use a shorter %g format instead. 116 BRILLO_EXPORT std::string ToString(double value); 117 // And the bool to be converted as true/false instead of 1/0. 118 BRILLO_EXPORT std::string ToString(bool value); 119 120 // Converts a byte-array into a string. This method doesn't perform any 121 // data re-encoding. It just takes every byte from the buffer and appends it 122 // to the string as a character. 123 BRILLO_EXPORT std::string GetBytesAsString(const std::vector<uint8_t>& buf); 124 125 // Converts a string into a byte-array. Opposite of GetBytesAsString(). 126 BRILLO_EXPORT std::vector<uint8_t> GetStringAsBytes(const std::string& str); 127 128 } // namespace string_utils 129 } // namespace brillo 130 131 #endif // LIBBRILLO_BRILLO_STRINGS_STRING_UTILS_H_ 132
