mdw@git.distorted.org.uk Git - mLib/blob - codec/base64.h

   1 /* -*-c-*-
   2  *
   3  * Base64 encoding and decoding
   4  *
   5  * (c) 1997 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of the mLib utilities library.
  11  *
  12  * mLib is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU Library General Public License as
  14  * published by the Free Software Foundation; either version 2 of the
  15  * License, or (at your option) any later version.
  16  *
  17  * mLib is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU Library General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Library General Public
  23  * License along with mLib; if not, write to the Free
  24  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  25  * MA 02111-1307, USA.
  26  */
  27
  28 #ifndef MLIB_BASE64_H
  29 #define MLIB_BASE64_H
  30
  31 #ifdef __cplusplus
  32   extern "C" {
  33 #endif
  34
  35 /*----- Header files ------------------------------------------------------*/
  36
  37 #ifndef MLIB_DSTR_H
  38 #  include "dstr.h"
  39 #endif
  40
  41 /*----- Data structures ---------------------------------------------------*/
  42
  43 typedef struct base64_ctx {
  44   unsigned long acc;                    /* Accumulator for output data */
  45   unsigned qsz;                         /* Length of data queued */
  46   unsigned lnlen;                       /* Length of the current line */
  47   const char *indent;                   /* Newline-and-indent string */
  48   unsigned maxline;                     /* Maximum permitted line length */
  49 } base64_ctx;
  50
  51 /*----- Functions provided ------------------------------------------------*/
  52
  53 /* --- @base64_encode@ --- *
  54  *
  55  * Arguments:   @base64_ctx *ctx@ = pointer to a context block
  56  *              @const void *p@ = pointer to a source buffer
  57  *              @size_t sz@ = size of the source buffer
  58  *              @dstr *d@ = pointer to destination string
  59  *
  60  * Returns:     ---
  61  *
  62  * Use:         Encodes a binary string in base64.  To flush out the final
  63  *              few characters (if necessary), pass a null source pointer.
  64  */
  65
  66 extern void base64_encode(base64_ctx */*ctx*/,
  67                           const void */*p*/, size_t /*sz*/,
  68                           dstr */*d*/);
  69
  70 /* --- @base64_decode@ --- *
  71  *
  72  * Arguments:   @base64_ctx *ctx@ = pointer to a context block
  73  *              @const void *p@ = pointer to a source buffer
  74  *              @size_t sz@ = size of the source buffer
  75  *              @dstr *d@ = pointer to destination string
  76  *
  77  * Returns:     ---
  78  *
  79  * Use:         Decodes a binary string in base64.  To flush out the final
  80  *              few characters (if necessary), pass a null source pointer.
  81  */
  82
  83 extern void base64_decode(base64_ctx */*ctx*/,
  84                           const void */*p*/, size_t /*sz*/,
  85                           dstr */*d*/);
  86
  87 /* --- @base64_init@ --- *
  88  *
  89  * Arguments:   @base64_ctx *ctx@ = pointer to context block to initialize
  90  *
  91  * Returns:     ---
  92  *
  93  * Use:         Initializes a base64 context properly.
  94  */
  95
  96 extern void base64_init(base64_ctx */*ctx*/);
  97
  98 /*----- That's all, folks -------------------------------------------------*/
  99
 100 #ifdef __cplusplus
 101   }
 102 #endif
 103
 104 #endif