text: /*
   * Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
   *
   * @APPLE_LICENSE_HEADER_START@
   * 
   * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   * 
   * This file contains Original Code and/or Modifications of Original Code
   * as defined in and that are subject to the Apple Public Source License
   * Version 2.0 (the 'License'). You may not use this file except in
   * compliance with the License. Please obtain a copy of the License at
   * http://www.opensource.apple.com/apsl/ and read it before using this
   * file.
   * 
   * The Original Code and all software distributed under the License are
   * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
   * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
   * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
   * Please see the License for the specific language governing rights and
   * limitations under the License.
   * 
   * @APPLE_LICENSE_HEADER_END@
   */
  /* ====================================================================
   * Copyright (c) 1995-1999 The Apache Group.  All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. All advertising materials mentioning features or use of this
   *    software must display the following acknowledgment:
   *    "This product includes software developed by the Apache Group
   *    for use in the Apache HTTP server project (http://www.apache.org/)."
   *
   * 4. The names "Apache Server" and "Apache Group" must not be used to
   *    endorse or promote products derived from this software without
   *    prior written permission. For written permission, please contact
   *    apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache"
   *    nor may "Apache" appear in their names without prior written
   *    permission of the Apache Group.
   *
   * 6. Redistributions of any form whatsoever must retain the following
   *    acknowledgment:
   *    "This product includes software developed by the Apache Group
   *    for use in the Apache HTTP server project (http://www.apache.org/)."
   *
   * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``AS IS'' AND ANY
   * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE APACHE GROUP OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
   * OF THE POSSIBILITY OF SUCH DAMAGE.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Group and was originally based
   * on public domain software written at the National Center for
   * Supercomputing Applications, University of Illinois, Urbana-Champaign.
   * For more information on the Apache Group and the Apache HTTP server
   * project, please see <http://www.apache.org/>.
   *
   */
  
  /* Base64 encoder/decoder. Originally Apache file ap_base64.c
   */
  
  #include <string.h>
  
  #include "base64.h"
  
  /* aaaack but it's fast and const should make it shared text page. */
  static const unsigned char pr2six[256] =
  {
      /* ASCII table */
      64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
      64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
      64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 62, 64, 64, 64, 63,
      52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 64, 64, 64, 64, 64, 64,
      64,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,
      15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 64, 64, 64, 64, 64,
      64, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
      41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 64, 64, 64, 64, 64,
      64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
      64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
      64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
      64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
      64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
      64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
      64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
      64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64
  };
  
  int Base64decode_len(const char *bufcoded)
  {
      int nbytesdecoded;
      register const unsigned char *bufin;
      register int nprbytes;
  
      bufin = (const unsigned char *) bufcoded;
      while (pr2six[*(bufin++)] <= 63);
  
      nprbytes = (bufin - (const unsigned char *) bufcoded) - 1;
      nbytesdecoded = ((nprbytes + 3) / 4) * 3;
  
      return nbytesdecoded + 1;
  }
  
  int Base64decode(char *bufplain, const char *bufcoded)
  {
      int nbytesdecoded;
      register const unsigned char *bufin;
      register unsigned char *bufout;
      register int nprbytes;
  
      bufin = (const unsigned char *) bufcoded;
      while (pr2six[*(bufin++)] <= 63);
      nprbytes = (bufin - (const unsigned char *) bufcoded) - 1;
      nbytesdecoded = ((nprbytes + 3) / 4) * 3;
  
      bufout = (unsigned char *) bufplain;
      bufin = (const unsigned char *) bufcoded;
  
      while (nprbytes > 4) {
      *(bufout++) =
          (unsigned char) (pr2six[*bufin] << 2 | pr2six[bufin[1]] >> 4);
      *(bufout++) =
          (unsigned char) (pr2six[bufin[1]] << 4 | pr2six[bufin[2]] >> 2);
      *(bufout++) =
          (unsigned char) (pr2six[bufin[2]] << 6 | pr2six[bufin[3]]);
      bufin += 4;
      nprbytes -= 4;
      }
  
      /* Note: (nprbytes == 1) would be an error, so just ingore that case */
      if (nprbytes > 1) {
      *(bufout++) =
          (unsigned char) (pr2six[*bufin] << 2 | pr2six[bufin[1]] >> 4);
      }
      if (nprbytes > 2) {
      *(bufout++) =
          (unsigned char) (pr2six[bufin[1]] << 4 | pr2six[bufin[2]] >> 2);
      }
      if (nprbytes > 3) {
      *(bufout++) =
          (unsigned char) (pr2six[bufin[2]] << 6 | pr2six[bufin[3]]);
      }
  
      *(bufout++) = '\0';
      nbytesdecoded -= (4 - nprbytes) & 3;
      return nbytesdecoded;
  }
  
  static const char basis_64[] =
      "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789!@";
  
  int Base64encode_len(int len)
  {
      return ((len + 2) / 3 * 4) + 1;
  }
  
  int Base64encode(char *encoded, const char *string, int len)
  {
      int i;
      char *p;
  
      p = encoded;
      for (i = 0; i < len - 2; i += 3) {
      *p++ = basis_64[(string[i] >> 2) & 0x3F];
      *p++ = basis_64[((string[i] & 0x3) << 4) |
                      ((int) (string[i + 1] & 0xF0) >> 4)];
      *p++ = basis_64[((string[i + 1] & 0xF) << 2) |
                      ((int) (string[i + 2] & 0xC0) >> 6)];
      *p++ = basis_64[string[i + 2] & 0x3F];
      }
      if (i < len) {
      *p++ = basis_64[(string[i] >> 2) & 0x3F];
      if (i == (len - 1)) {
          *p++ = basis_64[((string[i] & 0x3) << 4)];
          *p++ = '=';
      }
      else {
          *p++ = basis_64[((string[i] & 0x3) << 4) |
                          ((int) (string[i + 1] & 0xF0) >> 4)];
          *p++ = basis_64[((string[i + 1] & 0xF) << 2)];
      }
      *p++ = '=';
      }
  
      *p++ = '\0';
      return p - encoded;
  }
  