Line data    Source code

       1             : /* -*- Mode: c; c-basic-offset: 4; indent-tabs-mode: t; tab-width: 8; -*- */
       2             : /* cairo - a vector graphics library with display and print output
       3             :  *
       4             :  * Copyright © 2005-2007 Emmanuel Pacaud <emmanuel.pacaud@free.fr>
       5             :  * Copyright © 2009 Chris Wilson
       6             :  *
       7             :  * This library is free software; you can redistribute it and/or
       8             :  * modify it either under the terms of the GNU Lesser General Public
       9             :  * License version 2.1 as published by the Free Software Foundation
      10             :  * (the "LGPL") or, at your option, under the terms of the Mozilla
      11             :  * Public License Version 1.1 (the "MPL"). If you do not alter this
      12             :  * notice, a recipient may use your version of this file under either
      13             :  * the MPL or the LGPL.
      14             :  *
      15             :  * You should have received a copy of the LGPL along with this library
      16             :  * in the file COPYING-LGPL-2.1; if not, write to the Free Software
      17             :  * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
      18             :  * You should have received a copy of the MPL along with this library
      19             :  * in the file COPYING-MPL-1.1
      20             :  *
      21             :  * The contents of this file are subject to the Mozilla Public License
      22             :  * Version 1.1 (the "License"); you may not use this file except in
      23             :  * compliance with the License. You may obtain a copy of the License at
      24             :  * http://www.mozilla.org/MPL/
      25             :  *
      26             :  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
      27             :  * OF ANY KIND, either express or implied. See the LGPL or the MPL for
      28             :  * the specific language governing rights and limitations.
      29             :  *
      30             :  * The Original Code is the cairo graphics library.
      31             :  *
      32             :  * The Initial Developer of the Original Code is Red Hat, Inc.
      33             :  *
      34             :  * Author(s):
      35             :  *      Kristian Høgsberg <krh@redhat.com>
      36             :  *      Chris Wilson <chris@chris-wilson.co.uk>
      37             :  */
      38             : 
      39             : #include "cairoint.h"
      40             : #include "cairo-error-private.h"
      41             : #include "cairo-output-stream-private.h"
      42             : 
      43             : typedef struct _cairo_base64_stream {
      44             :     cairo_output_stream_t base;
      45             :     cairo_output_stream_t *output;
      46             :     unsigned int in_mem;
      47             :     unsigned int trailing;
      48             :     unsigned char src[3];
      49             : } cairo_base64_stream_t;
      50             : 
      51             : static char const base64_table[64] =
      52             : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
      53             : 
      54             : static cairo_status_t
      55           0 : _cairo_base64_stream_write (cairo_output_stream_t *base,
      56             :                             const unsigned char   *data,
      57             :                             unsigned int           length)
      58             : {
      59           0 :     cairo_base64_stream_t * stream = (cairo_base64_stream_t *) base;
      60           0 :     unsigned char *src = stream->src;
      61             :     unsigned int i;
      62             : 
      63           0 :     if (stream->in_mem + length < 3) {
      64           0 :         for (i = 0; i < length; i++) {
      65           0 :             src[i + stream->in_mem] = *data++;
      66             :         }
      67           0 :         stream->in_mem += length;
      68           0 :         return CAIRO_STATUS_SUCCESS;
      69             :     }
      70             : 
      71             :     do {
      72             :         unsigned char dst[4];
      73             : 
      74           0 :         for (i = stream->in_mem; i < 3; i++) {
      75           0 :             src[i] = *data++;
      76           0 :             length--;
      77             :         }
      78           0 :         stream->in_mem = 0;
      79             : 
      80           0 :         dst[0] = base64_table[src[0] >> 2];
      81           0 :         dst[1] = base64_table[(src[0] & 0x03) << 4 | src[1] >> 4];
      82           0 :         dst[2] = base64_table[(src[1] & 0x0f) << 2 | src[2] >> 6];
      83           0 :         dst[3] = base64_table[src[2] & 0xfc >> 2];
      84             :         /* Special case for the last missing bits */
      85           0 :         switch (stream->trailing) {
      86             :             case 2:
      87           0 :                 dst[2] = '=';
      88             :             case 1:
      89           0 :                 dst[3] = '=';
      90             :             default:
      91           0 :                 break;
      92             :         }
      93           0 :         _cairo_output_stream_write (stream->output, dst, 4);
      94           0 :     } while (length >= 3);
      95             : 
      96           0 :     for (i = 0; i < length; i++) {
      97           0 :         src[i] = *data++;
      98             :     }
      99           0 :     stream->in_mem = length;
     100             : 
     101           0 :     return _cairo_output_stream_get_status (stream->output);
     102             : }
     103             : 
     104             : static cairo_status_t
     105           0 : _cairo_base64_stream_close (cairo_output_stream_t *base)
     106             : {
     107           0 :     cairo_base64_stream_t *stream = (cairo_base64_stream_t *) base;
     108           0 :     cairo_status_t status = CAIRO_STATUS_SUCCESS;
     109             : 
     110           0 :     if (stream->in_mem > 0) {
     111           0 :         memset (stream->src + stream->in_mem, 0, 3 - stream->in_mem);
     112           0 :         stream->trailing = 3 - stream->in_mem;
     113           0 :         stream->in_mem = 3;
     114           0 :         status = _cairo_base64_stream_write (base, NULL, 0);
     115             :     }
     116             : 
     117           0 :     return status;
     118             : }
     119             : 
     120             : cairo_output_stream_t *
     121           0 : _cairo_base64_stream_create (cairo_output_stream_t *output)
     122             : {
     123             :     cairo_base64_stream_t *stream;
     124             : 
     125           0 :     if (output->status)
     126           0 :         return _cairo_output_stream_create_in_error (output->status);
     127             : 
     128           0 :     stream = malloc (sizeof (cairo_base64_stream_t));
     129           0 :     if (unlikely (stream == NULL)) {
     130           0 :         _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
     131           0 :         return (cairo_output_stream_t *) &_cairo_output_stream_nil;
     132             :     }
     133             : 
     134           0 :     _cairo_output_stream_init (&stream->base,
     135             :                                _cairo_base64_stream_write,
     136             :                                NULL,
     137             :                                _cairo_base64_stream_close);
     138             : 
     139           0 :     stream->output = output;
     140           0 :     stream->in_mem = 0;
     141           0 :     stream->trailing = 0;
     142             : 
     143           0 :     return &stream->base;
     144             : }