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) {
38 return (isalnum(c) || (c == '+') || (c == '/'));
41 std::string base64_encode(unsigned char const* bytes_to_encode, unsigned int in_len) {
45 unsigned char char_array_3[3];
46 unsigned char char_array_4[4];
49 char_array_3[i++] = *(bytes_to_encode++);
51 char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
52 char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
53 char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
54 char_array_4[3] = char_array_3[2] & 0x3f;
56 for(i = 0; (i <4) ; i++)
57 ret += base64_chars[char_array_4[i]];
64 for(j = i; j < 3; j++)
65 char_array_3[j] = '\0';
67 char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
68 char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
69 char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
70 char_array_4[3] = char_array_3[2] & 0x3f;
72 for (j = 0; (j < i + 1); j++)
73 ret += base64_chars[char_array_4[j]];
75 // Don't pad it with =
85 std::string base64_decode(std::string const& encoded_string) {
86 int in_len = encoded_string.size();
90 unsigned char char_array_4[4], char_array_3[3];
93 while (in_len-- && ( encoded_string[in_] != '=') && is_base64(encoded_string[in_])) {
94 char_array_4[i++] = encoded_string[in_]; in_++;
96 for (i = 0; i <4; i++)
97 char_array_4[i] = base64_chars.find(char_array_4[i]);
99 char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
100 char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
101 char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
103 for (i = 0; (i < 3); i++)
104 ret += char_array_3[i];
110 for (j = i; j <4; j++)
113 for (j = 0; j <4; j++)
114 char_array_4[j] = base64_chars.find(char_array_4[j]);
116 char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
117 char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
118 char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
120 for (j = 0; (j < i - 1); j++) ret += char_array_3[j];