1 2 //********************************************************************* 3 //* C_Base64 - a simple base64 encoder and decoder. 4 //* 5 //* Copyright (c) 1999, Bob Withers - bwit (at) pobox.com 6 //* 7 //* This code may be freely used for any purpose, either personal 8 //* or commercial, provided the authors copyright notice remains 9 //* intact. 10 //********************************************************************* 11 12 #ifndef TALK_BASE_BASE64_H__ 13 #define TALK_BASE_BASE64_H__ 14 15 #include <string> 16 #include <vector> 17 18 namespace talk_base { 19 20 class Base64 21 { 22 public: 23 enum DecodeOption { 24 DO_PARSE_STRICT = 1, // Parse only base64 characters 25 DO_PARSE_WHITE = 2, // Parse only base64 and whitespace characters 26 DO_PARSE_ANY = 3, // Parse all characters 27 DO_PARSE_MASK = 3, 28 29 DO_PAD_YES = 4, // Padding is required 30 DO_PAD_ANY = 8, // Padding is optional 31 DO_PAD_NO = 12, // Padding is disallowed 32 DO_PAD_MASK = 12, 33 34 DO_TERM_BUFFER = 16, // Must termiante at end of buffer 35 DO_TERM_CHAR = 32, // May terminate at any character boundary 36 DO_TERM_ANY = 48, // May terminate at a sub-character bit offset 37 DO_TERM_MASK = 48, 38 39 // Strictest interpretation 40 DO_STRICT = DO_PARSE_STRICT | DO_PAD_YES | DO_TERM_BUFFER, 41 42 DO_LAX = DO_PARSE_ANY | DO_PAD_ANY | DO_TERM_CHAR, 43 }; 44 typedef int DecodeFlags; 45 46 static bool IsBase64Char(char ch); 47 48 // Determines whether the given string consists entirely of valid base64 49 // encoded characters. 50 static bool IsBase64Encoded(const std::string& str); 51 52 static void EncodeFromArray(const void* data, size_t len, 53 std::string* result); 54 static bool DecodeFromArray(const char* data, size_t len, DecodeFlags flags, 55 std::string* result, size_t* data_used); 56 static bool DecodeFromArray(const char* data, size_t len, DecodeFlags flags, 57 std::vector<char>* result, size_t* data_used); 58 59 // Convenience Methods 60 static inline std::string Encode(const std::string& data) { 61 std::string result; 62 EncodeFromArray(data.data(), data.size(), &result); 63 return result; 64 } 65 static inline std::string Decode(const std::string& data, DecodeFlags flags) { 66 std::string result; 67 DecodeFromArray(data.data(), data.size(), flags, &result, NULL); 68 return result; 69 } 70 static inline bool Decode(const std::string& data, DecodeFlags flags, 71 std::string* result, size_t* data_used) 72 { 73 return DecodeFromArray(data.data(), data.size(), flags, result, data_used); 74 } 75 static inline bool Decode(const std::string& data, DecodeFlags flags, 76 std::vector<char>* result, size_t* data_used) 77 { 78 return DecodeFromArray(data.data(), data.size(), flags, result, data_used); 79 } 80 81 private: 82 static const std::string Base64Table; 83 static const unsigned char DecodeTable[]; 84 85 static size_t GetNextQuantum(DecodeFlags parse_flags, bool illegal_pads, 86 const char* data, size_t len, size_t* dpos, 87 unsigned char qbuf[4], bool* padded); 88 template<typename T> 89 static bool DecodeFromArrayTemplate(const char* data, size_t len, 90 DecodeFlags flags, T* result, 91 size_t* data_used); 92 }; 93 94 } // namespace talk_base 95 96 #endif // TALK_BASE_BASE64_H__ 97
