2 base64.cpp and base64.h
4 Copyright (C) 2004-2008 René Nyffenegger
6 This source code is provided 'as-is', without any express or implied
7 warranty. In no event will the author be held liable for any damages
8 arising from the use of this software.
10 Permission is granted to anyone to use this software for any purpose,
11 including commercial applications, and to alter it and redistribute it
12 freely, subject to the following restrictions:
14 1. The origin of this source code must not be misrepresented; you must not
15 claim that you wrote the original source code. If you use this source code
16 in a product, an acknowledgment in the product documentation would be
17 appreciated but is not required.
19 2. Altered source versions must be plainly marked as such, and must not be
20 misrepresented as being the original source code.
22 3. This notice may not be removed or altered from any source distribution.
24 René Nyffenegger rene.nyffenegger@adp-gmbh.ch
31 static const std::string base64_chars
=
32 "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
33 "abcdefghijklmnopqrstuvwxyz"
37 static inline bool is_base64(unsigned char c
)
39 return isalnum(c
) || c
== '+' || c
== '/' || c
== '=';
42 bool base64_is_valid(std::string
const& s
)
50 std::string
base64_encode(unsigned char const* bytes_to_encode
, unsigned int in_len
) {
54 unsigned char char_array_3
[3];
55 unsigned char char_array_4
[4];
58 char_array_3
[i
++] = *(bytes_to_encode
++);
60 char_array_4
[0] = (char_array_3
[0] & 0xfc) >> 2;
61 char_array_4
[1] = ((char_array_3
[0] & 0x03) << 4) + ((char_array_3
[1] & 0xf0) >> 4);
62 char_array_4
[2] = ((char_array_3
[1] & 0x0f) << 2) + ((char_array_3
[2] & 0xc0) >> 6);
63 char_array_4
[3] = char_array_3
[2] & 0x3f;
65 for(i
= 0; (i
<4) ; i
++)
66 ret
+= base64_chars
[char_array_4
[i
]];
73 for(j
= i
; j
< 3; j
++)
74 char_array_3
[j
] = '\0';
76 char_array_4
[0] = (char_array_3
[0] & 0xfc) >> 2;
77 char_array_4
[1] = ((char_array_3
[0] & 0x03) << 4) + ((char_array_3
[1] & 0xf0) >> 4);
78 char_array_4
[2] = ((char_array_3
[1] & 0x0f) << 2) + ((char_array_3
[2] & 0xc0) >> 6);
79 char_array_4
[3] = char_array_3
[2] & 0x3f;
81 for (j
= 0; (j
< i
+ 1); j
++)
82 ret
+= base64_chars
[char_array_4
[j
]];
84 // Don't pad it with =
94 std::string
base64_decode(std::string
const& encoded_string
) {
95 int in_len
= encoded_string
.size();
99 unsigned char char_array_4
[4], char_array_3
[3];
102 while (in_len
-- && ( encoded_string
[in_
] != '=') && is_base64(encoded_string
[in_
])) {
103 char_array_4
[i
++] = encoded_string
[in_
]; in_
++;
105 for (i
= 0; i
<4; i
++)
106 char_array_4
[i
] = base64_chars
.find(char_array_4
[i
]);
108 char_array_3
[0] = (char_array_4
[0] << 2) + ((char_array_4
[1] & 0x30) >> 4);
109 char_array_3
[1] = ((char_array_4
[1] & 0xf) << 4) + ((char_array_4
[2] & 0x3c) >> 2);
110 char_array_3
[2] = ((char_array_4
[2] & 0x3) << 6) + char_array_4
[3];
112 for (i
= 0; (i
< 3); i
++)
113 ret
+= char_array_3
[i
];
119 for (j
= i
; j
<4; j
++)
122 for (j
= 0; j
<4; j
++)
123 char_array_4
[j
] = base64_chars
.find(char_array_4
[j
]);
125 char_array_3
[0] = (char_array_4
[0] << 2) + ((char_array_4
[1] & 0x30) >> 4);
126 char_array_3
[1] = ((char_array_4
[1] & 0xf) << 4) + ((char_array_4
[2] & 0x3c) >> 2);
127 char_array_3
[2] = ((char_array_4
[2] & 0x3) << 6) + char_array_4
[3];
129 for (j
= 0; (j
< i
- 1); j
++) ret
+= char_array_3
[j
];