Bridges-C++  3.4.4
Bridges(C++ API)
base64.h
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1 #ifndef _BASE64_H_
2 #define _BASE64_H_
3 
4 #include <iostream>
5 #include <string>
6 #include <vector>
7 using namespace std;
8 
42 namespace bridges {
43  typedef unsigned char BYTE;
44 
45  namespace base64 {
46 
47  const string base64_chars =
48  "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
49  "abcdefghijklmnopqrstuvwxyz"
50  "0123456789+/";
51 
52  inline bool is_base64(BYTE c) {
53  return (isalnum(c) || (c == '+') || (c == '/'));
54  }
55 
56  string inline encode(BYTE const* buf, unsigned int bufLen) {
57  string ret;
58  int i = 0;
59  int j = 0;
60  BYTE char_array_3[3];
61  BYTE char_array_4[4];
62 
63  while (bufLen--) {
64  // 3 chars become 4 chars in base 64 representation
65  // hence the char arrays of 3 and 4
66  char_array_3[i++] = *(buf++);
67  if (i == 3) {
68  char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
69  char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
70  char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
71  char_array_4[3] = char_array_3[2] & 0x3f;
72 
73  for (i = 0; (i < 4) ; i++)
74  ret += base64_chars[char_array_4[i]];
75  i = 0;
76  }
77  }
78 
79  // handle any left over bytes, by padding with end of string chars
80  if (i) {
81  for (j = i; j < 3; j++)
82  char_array_3[j] = '\0';
83 
84  char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
85  char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
86  char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
87  char_array_4[3] = char_array_3[2] & 0x3f;
88 
89  for (j = 0; (j < i + 1); j++)
90  ret += base64_chars[char_array_4[j]];
91 
92  // not sure what this does!
93  while ((i++ < 3))
94  ret += '=';
95  }
96 
97  return ret;
98  }
99 
100  vector<BYTE> inline decode(string const& encoded_string) {
101  size_t in_len = encoded_string.size();
102  int i = 0;
103  // int j = 0;
104  int in_ = 0;
105  BYTE char_array_4[4], char_array_3[3];
106  vector<BYTE> ret;
107 
108  while (in_len-- && ( encoded_string[in_] != '=') && is_base64(encoded_string[in_])) {
109  char_array_4[i++] = encoded_string[in_];
110  in_++;
111  if (i == 4) {
112  for (i = 0; i < 4; i++)
113  char_array_4[i] = (BYTE) base64_chars.find(char_array_4[i]);
114 
115  char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
116  char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
117  char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
118 
119  for (i = 0; (i < 3); i++)
120  ret.push_back(char_array_3[i]);
121  i = 0;
122  }
123  }
124 
125  if (i) {
126  for (int j = i; j < 4; j++)
127  char_array_4[j] = 0;
128 
129  for (int j = 0; j < 4; j++)
130  char_array_4[j] = (BYTE) base64_chars.find(char_array_4[j]);
131 
132  char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
133  char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
134  char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
135 
136  for (int j = 0; (j < i - 1); j++)
137  ret.push_back(char_array_3[j]);
138  }
139 
140  return ret;
141  }
142 
143  } // end namespace base64
144 } // end namespace bridges
145 
146 #endif
bool is_base64(BYTE c)
Definition: base64.h:52
const string base64_chars
Definition: base64.h:47
vector< BYTE > decode(string const &encoded_string)
Definition: base64.h:100
string encode(BYTE const *buf, unsigned int bufLen)
Definition: base64.h:56
these methods convert byte arrays in to base64 codes and are used in BRIDGES to represent the color a...
Definition: alltypes.h:4
unsigned char BYTE
Definition: base64.h:43