1 /* base32.h -- Encode binary data using printable characters.
2    Copyright (C) 2004-2006, 2009-2018 Free Software Foundation, Inc.
3    Adapted from Simon Josefsson's base64 code by Gijs van Tulder.
4 
5    This program is free software; you can redistribute it and/or modify
6    it under the terms of the GNU General Public License as published by
7    the Free Software Foundation; either version 3, or (at your option)
8    any later version.
9 
10    This program 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 General Public License for more details.
14 
15    You should have received a copy of the GNU 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 size_t. */
22 # include <stddef.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   unsigned 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, size_t inlen,
40                            char *restrict out, size_t outlen);
41 
42 extern size_t base32_encode_alloc (const char *in, size_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, size_t inlen,
48                                char *restrict out, size_t *outlen);
49 
50 extern bool base32_decode_alloc_ctx (struct base32_decode_context *ctx,
51                                      const char *in, size_t inlen,
52                                      char **out, size_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 */
61