1 /****************************************************************************
2 * Function to encode in Base64
3 *
4 * Written by Lauri Alanko
5 *
6 *****************************************************************************/
8 #include "common.h"
9 #include "base64.h"
11 char *
12 base64 (const char *bin, size_t len)
13 {
15 char *buf = (char *) malloc ((len + 2) / 3 * 4 + 1);
16 size_t i = 0, j = 0;
18 char BASE64_END = '=';
19 char base64_table[64];
20 strncpy (base64_table, "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/", 64);
22 while (j < len - 2) {
23 buf[i++] = base64_table[bin[j] >> 2];
24 buf[i++] = base64_table[((bin[j] & 3) << 4) | (bin[j + 1] >> 4)];
25 buf[i++] = base64_table[((bin[j + 1] & 15) << 2) | (bin[j + 2] >> 6)];
26 buf[i++] = base64_table[bin[j + 2] & 63];
27 j += 3;
28 }
30 switch (len - j) {
31 case 1:
32 buf[i++] = base64_table[bin[j] >> 2];
33 buf[i++] = base64_table[(bin[j] & 3) << 4];
34 buf[i++] = BASE64_END;
35 buf[i++] = BASE64_END;
36 break;
37 case 2:
38 buf[i++] = base64_table[bin[j] >> 2];
39 buf[i++] = base64_table[((bin[j] & 3) << 4) | (bin[j + 1] >> 4)];
40 buf[i++] = base64_table[(bin[j + 1] & 15) << 2];
41 buf[i++] = BASE64_END;
42 break;
43 case 0:
44 break;
45 }
47 buf[i] = '\0';
48 return buf;
49 }