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view src/base64/base64.c @ 175:805abb75b20c

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removed links to oku's old email address
author meillo@marmaro.de
date Fri, 23 Jul 2010 10:20:27 +0200
parents 26e34ae9a3e3
children
line source
1 /* base64.c, Copyright 2000 (C) Oliver Kurth,
2 *
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2 of the License, or
6 * (at your option) any later version.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
16 */
17
18 /* see also RFC 1341 */
19
20 #include <glib.h>
21 #include <string.h>
22 #include "base64.h"
23
24 gchar*
25 base64_encode(guchar * buf, gint len)
26 {
27 guchar *outbuf, *q;
28 gchar enc[64];
29 gint i = 0, j = 0;
30 guint in0, in1, in2;
31
32 for (; i < 26; i++)
33 enc[i] = (gchar) ('A' + j++);
34 j = 0;
35 for (; i < 52; i++)
36 enc[i] = (gchar) ('a' + j++);
37 j = 0;
38 for (; i < 62; i++)
39 enc[i] = (gchar) ('0' + j++);
40 enc[i++] = '+';
41 enc[i++] = '/';
42
43 outbuf = g_malloc(((len + 3) * 8) / 6);
44 q = outbuf;
45
46 i = 0;
47 while (i < len - 2) {
48 in0 = buf[i++];
49 in1 = buf[i++];
50 in2 = buf[i++];
51
52 *(q++) = enc[(in0 >> 2) & 0x3f];
53 *(q++) = enc[((in0 << 4) | (in1 >> 4)) & 0x3f];
54 *(q++) = enc[((in1 << 2) | (in2 >> 6)) & 0x3f];
55 *(q++) = enc[in2 & 0x3f];
56 }
57 if ((len - i) == 1) {
58 in0 = buf[i++];
59 *(q++) = enc[(in0 >> 2) & 0x3f];
60 *(q++) = enc[(in0 << 4) & 0x3f];
61 *(q++) = '=';
62 *(q++) = '=';
63 } else if ((len - i) == 2) {
64 in0 = buf[i++];
65 in1 = buf[i++];
66 *(q++) = enc[(in0 >> 2) & 0x3f];
67 *(q++) = enc[((in0 << 4) | (in1 >> 4)) & 0x3f];
68 *(q++) = enc[(in1 << 2) & 0x3f];
69 *(q++) = '=';
70 }
71 *q = 0;
72
73 return outbuf;
74 }
75
76 gchar *base64_decode(gchar * buf, gint * size)
77 {
78 guchar *p = buf, *q;
79 guint in[4];
80 /* gchar *out = g_malloc(((strlen(buf)+3) * 3) / 4 + 1); */
81 gchar *out = g_malloc((strlen(buf) + 3) + 1);
82
83 q = out;
84 *size = 0;
85
86 *q = 0;
87
88 while (*p) {
89 int i = 0;
90 while (i < 4) {
91 if (!*p)
92 break;
93 if ((*p >= 'A') && (*p <= 'Z'))
94 in[i++] = *p - 'A';
95 else if ((*p >= 'a') && (*p <= 'z'))
96 in[i++] = (*p - 'a') + 26;
97 else if ((*p >= '0') && (*p <= '9'))
98 in[i++] = (*p - '0') + 52;
99 else if (*p == '+')
100 in[i++] = 62;
101 else if (*p == '/')
102 in[i++] = 63;
103 else if (*p == '=') {
104 in[i++] = 0;
105 p++;
106 break;
107 } else if ((*p != '\r') && (*p != '\n')) {
108 p++;
109 break;
110 }
111 p++;
112 }
113 if ((i == 4) || (p[-1] == '=')) {
114 *(q++) = ((in[0] << 2) | (in[1] >> 4));
115 *(q++) = ((in[1] << 4) | (in[2] >> 2));
116 *(q++) = ((in[2] << 6) | in[3]);
117 if (p[-1] == '=') {
118 if (i == 3) {
119 (*size)++;
120 } else if (i == 4) {
121 (*size) += 2;
122 }
123 } else {
124 *size += 3;
125 }
126 }
127 }
128 return out;
129 }