1 /* base32.h -- Encode binary data using printable characters.
2 Copyright (C) 2004-2006, 2009-2021 Free Software Foundation, Inc.
3 Adapted from Simon Josefsson's base64 code by Gijs van Tulder.
4
5 This file is free software: you can redistribute it and/or modify
6 it under the terms of the GNU Lesser General Public License as
7 published by the Free Software Foundation; either version 2.1 of the
8 License, or (at your option) any later version.
9
10 This file is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public License
16 along with this program. If not, see <https://www.gnu.org/licenses/>. */
17
18 #ifndef BASE32_H
19 # define BASE32_H
20
21 /* Get idx_t. */
22 # include <idx.h>
23
24 /* Get bool. */
25 # include <stdbool.h>
26
27 /* This uses that the expression (n+(k-1))/k means the smallest
28 integer >= n/k, i.e., the ceiling of n/k. */
29 # define BASE32_LENGTH(inlen) ((((inlen) + 4) / 5) * 8)
30
31 struct base32_decode_context
32 {
33 int i;
34 char buf[8];
35 };
36
37 extern bool isbase32 (char ch) _GL_ATTRIBUTE_CONST;
38
39 extern void base32_encode (const char *restrict in, idx_t inlen,
40 char *restrict out, idx_t outlen);
41
42 extern idx_t base32_encode_alloc (const char *in, idx_t inlen, char **out);
43
44 extern void base32_decode_ctx_init (struct base32_decode_context *ctx);
45
46 extern bool base32_decode_ctx (struct base32_decode_context *ctx,
47 const char *restrict in, idx_t inlen,
48 char *restrict out, idx_t *outlen);
49
50 extern bool base32_decode_alloc_ctx (struct base32_decode_context *ctx,
51 const char *in, idx_t inlen,
52 char **out, idx_t *outlen);
53
54 #define base32_decode(in, inlen, out, outlen) \
55 base32_decode_ctx (NULL, in, inlen, out, outlen)
56
57 #define base32_decode_alloc(in, inlen, out, outlen) \
58 base32_decode_alloc_ctx (NULL, in, inlen, out, outlen)
59
60 #endif /* BASE32_H */