1 /* base64.h -- Encode binary data using printable characters. 2 Copyright (C) 2004-2006, 2009-2021 Free Software Foundation, Inc. 3 Written by Simon Josefsson. 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU Lesser General Public License as published by 7 the Free Software Foundation; either version 2.1, 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 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 BASE64_H 19 # define BASE64_H 20 21 /* Get size_t. */ 22 # include <stddef.h> 23 24 /* Get bool. */ 25 # include <stdbool.h> 26 27 # ifdef __cplusplus 28 extern "C" { 29 # endif 30 31 /* This uses that the expression (n+(k-1))/k means the smallest 32 integer >= n/k, i.e., the ceiling of n/k. */ 33 # define BASE64_LENGTH(inlen) ((((inlen) + 2) / 3) * 4) 34 35 struct base64_decode_context 36 { 37 unsigned int i; 38 char buf[4]; 39 }; 40 41 extern bool isbase64 (char ch) _GL_ATTRIBUTE_CONST; 42 43 extern void base64_encode (const char *restrict in, size_t inlen, 44 char *restrict out, size_t outlen); 45 46 extern size_t base64_encode_alloc (const char *in, size_t inlen, char **out); 47 48 extern void base64_decode_ctx_init (struct base64_decode_context *ctx); 49 50 extern bool base64_decode_ctx (struct base64_decode_context *ctx, 51 const char *restrict in, size_t inlen, 52 char *restrict out, size_t *outlen); 53 54 extern bool base64_decode_alloc_ctx (struct base64_decode_context *ctx, 55 const char *in, size_t inlen, 56 char **out, size_t *outlen); 57 58 #define base64_decode(in, inlen, out, outlen) \ 59 base64_decode_ctx (NULL, in, inlen, out, outlen) 60 61 #define base64_decode_alloc(in, inlen, out, outlen) \ 62 base64_decode_alloc_ctx (NULL, in, inlen, out, outlen) 63 64 # ifdef __cplusplus 65 } 66 # endif 67 68 #endif /* BASE64_H */ 69