xref: /third_party/ffmpeg/tests/base64.c (revision cabdff1a)
1/*
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19/*
20 * Based on libavutil/base64.c
21 */
22
23#include <stdio.h>
24
25int main(void)
26{
27    static const char b64[] =
28        "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
29    unsigned i_bits = 0;
30    int i_shift     = 0;
31    int out_len     = 0;
32    int in;
33
34#define putb64()                                        \
35    do {                                                \
36        putchar(b64[(i_bits << 6 >> i_shift) & 0x3f]);  \
37        out_len++;                                      \
38        i_shift -= 6;                                   \
39    } while (0)
40
41    while ((in = getchar()) != EOF) {
42        i_bits   = (i_bits << 8) + in;
43        i_shift += 8;
44        while (i_shift > 6)
45            putb64();
46    }
47    while (i_shift > 0)
48        putb64();
49    while (out_len++ & 3)
50        putchar('=');
51    putchar('\n');
52
53    return 0;
54}
55