base64.c
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- /* @(#)base64.c 1.2 99/12/19 Copyright 1998,1999 Heiko Eissfeldt */
- #ifndef lint
- static char sccsid[] =
- "@(#)base64.c 1.2 99/12/19 Copyright 1998,1999 Heiko Eissfeldt";
- #endif
- /*____________________________________________________________________________
- //
- // CD Index - The Internet CD Index
- //
- // This program is free software; you can redistribute it and/or modify
- // it under the terms of the GNU General Public License as published by
- // the Free Software Foundation; either version 2 of the License, or
- // (at your option) any later version.
- //
- // This program is distributed in the hope that it will be useful,
- // but WITHOUT ANY WARRANTY; without even the implied warranty of
- // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- // GNU General Public License for more details.
- //
- // You should have received a copy of the GNU General Public License
- // along with this program; if not, write to the Free Software
- // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- //
- // $Id: base64.c,v 1.1.1.3 1999/04/29 00:57:14 marc Exp $
- //____________________________________________________________________________
- */
- /*
- * Program: RFC-822 routines (originally from SMTP)
- *
- * Author: Mark Crispin
- * Networks and Distributed Computing
- * Computing & Communications
- * University of Washington
- * Administration Building, AG-44
- * Seattle, WA 98195
- * Internet: MRC@CAC.Washington.EDU
- *
- * Date: 27 July 1988
- * Last Edited: 10 September 1998
- *
- * Sponsorship: The original version of this work was developed in the
- * Symbolic Systems Resources Group of the Knowledge Systems
- * Laboratory at Stanford University in 1987-88, and was funded
- * by the Biomedical Research Technology Program of the National
- * Institutes of Health under grant number RR-00785.
- *
- * Original version Copyright 1988 by The Leland Stanford Junior University
- * Copyright 1998 by the University of Washington
- *
- * Permission to use, copy, modify, and distribute this software and its
- * documentation for any purpose and without fee is hereby granted, provided
- * that the above copyright notices appear in all copies and that both the
- * above copyright notices and this permission notice appear in supporting
- * documentation, and that the name of the University of Washington or The
- * Leland Stanford Junior University not be used in advertising or publicity
- * pertaining to distribution of the software without specific, written prior
- * permission. This software is made available "as is", and
- * THE UNIVERSITY OF WASHINGTON AND THE LELAND STANFORD JUNIOR UNIVERSITY
- * DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, WITH REGARD TO THIS SOFTWARE,
- * INCLUDING WITHOUT LIMITATION ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
- * FITNESS FOR A PARTICULAR PURPOSE, AND IN NO EVENT SHALL THE UNIVERSITY OF
- * WASHINGTON OR THE LELAND STANFORD JUNIOR UNIVERSITY BE LIABLE FOR ANY
- * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
- * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
- * CONTRACT, TORT (INCLUDING NEGLIGENCE) OR STRICT LIABILITY, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- *
- */
- #include "config.h"
- #include <ctype.h>
- #include <stdio.h>
- #include <time.h>
- #include <stdlib.h>
- #include "base64.h"
- /* NOTE: This is not true RFC822 anymore. The use of the characters
- // '/', '+', and '=' is no bueno when the ID will be used as part of a URL.
- // '_', '.', and '-' have been used instead
- */
- /* Convert binary contents to BASE64
- * Accepts: source
- * length of source
- * pointer to return destination length
- * Returns: destination as BASE64
- */
- unsigned char *rfc822_binary (src, srcl, len)
- char *src;
- unsigned long srcl;
- unsigned long *len;
- {
- unsigned char *ret,*d;
- unsigned char *s = (unsigned char *) src;
- char *v = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789._";
- unsigned long i = ((srcl + 2) / 3) * 4;
- *len = i += 2 * ((i / 60) + 1);
- d = ret = (unsigned char *) malloc ((size_t) ++i);
- for (i = 0; srcl; s += 3) { /* process tuplets */
- *d++ = v[s[0] >> 2]; /* byte 1: high 6 bits (1) */
- /* byte 2: low 2 bits (1), high 4 bits (2) */
- *d++ = v[((s[0] << 4) + (--srcl ? (s[1] >> 4) : 0)) & 0x3f];
- /* byte 3: low 4 bits (2), high 2 bits (3) */
- *d++ = srcl ? v[((s[1] << 2) + (--srcl ? (s[2] >> 6) : 0)) & 0x3f] : '-';
- /* byte 4: low 6 bits (3) */
- *d++ = srcl ? v[s[2] & 0x3f] : '-';
- if (srcl) srcl--; /* count third character if processed */
- if ((++i) == 15) { /* output 60 characters? */
- i = 0; /* restart line break count, insert CRLF */
- *d++ = ' 15'; *d++ = ' 12';
- }
- }
- *d = ' '; /* tie off string */
- return ret; /* return the resulting string */
- }