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
4 * Copyright © 2005 Red Hat, Inc
6 * This library is free software; you can redistribute it and/or
7 * modify it either under the terms of the GNU Lesser General Public
8 * License version 2.1 as published by the Free Software Foundation
9 * (the "LGPL") or, at your option, under the terms of the Mozilla
10 * Public License Version 1.1 (the "MPL"). If you do not alter this
11 * notice, a recipient may use your version of this file under either
12 * the MPL or the LGPL.
14 * You should have received a copy of the LGPL along with this library
15 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
17 * You should have received a copy of the MPL along with this library
18 * in the file COPYING-MPL-1.1
20 * The contents of this file are subject to the Mozilla Public License
21 * Version 1.1 (the "License"); you may not use this file except in
22 * compliance with the License. You may obtain a copy of the License at
23 * http://www.mozilla.org/MPL/
25 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
26 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
27 * the specific language governing rights and limitations.
29 * The Original Code is the cairo graphics library.
31 * The Initial Developer of the Original Code is Red Hat, Inc.
34 * Kristian Høgsberg <krh@redhat.com>
38 #include "cairo-error-private.h"
39 #include "cairo-output-stream-private.h"
41 typedef struct _cairo_base85_stream
{
42 cairo_output_stream_t base
;
43 cairo_output_stream_t
*output
;
44 unsigned char four_tuple
[4];
46 } cairo_base85_stream_t
;
49 _expand_four_tuple_to_five (unsigned char four_tuple
[4],
50 unsigned char five_tuple
[5],
51 cairo_bool_t
*all_zero
)
56 value
= four_tuple
[0] << 24 | four_tuple
[1] << 16 | four_tuple
[2] << 8 | four_tuple
[3];
59 for (i
= 0; i
< 5; i
++) {
61 if (digit
!= 0 && all_zero
)
63 five_tuple
[4-i
] = digit
+ 33;
69 _cairo_base85_stream_write (cairo_output_stream_t
*base
,
70 const unsigned char *data
,
73 cairo_base85_stream_t
*stream
= (cairo_base85_stream_t
*) base
;
74 const unsigned char *ptr
= data
;
75 unsigned char five_tuple
[5];
79 stream
->four_tuple
[stream
->pending
++] = *ptr
++;
81 if (stream
->pending
== 4) {
82 _expand_four_tuple_to_five (stream
->four_tuple
, five_tuple
, &is_zero
);
84 _cairo_output_stream_write (stream
->output
, "z", 1);
86 _cairo_output_stream_write (stream
->output
, five_tuple
, 5);
91 return _cairo_output_stream_get_status (stream
->output
);
95 _cairo_base85_stream_close (cairo_output_stream_t
*base
)
97 cairo_base85_stream_t
*stream
= (cairo_base85_stream_t
*) base
;
98 unsigned char five_tuple
[5];
100 if (stream
->pending
) {
101 memset (stream
->four_tuple
+ stream
->pending
, 0, 4 - stream
->pending
);
102 _expand_four_tuple_to_five (stream
->four_tuple
, five_tuple
, NULL
);
103 _cairo_output_stream_write (stream
->output
, five_tuple
, stream
->pending
+ 1);
106 return _cairo_output_stream_get_status (stream
->output
);
109 cairo_output_stream_t
*
110 _cairo_base85_stream_create (cairo_output_stream_t
*output
)
112 cairo_base85_stream_t
*stream
;
115 return _cairo_output_stream_create_in_error (output
->status
);
117 stream
= malloc (sizeof (cairo_base85_stream_t
));
118 if (unlikely (stream
== NULL
)) {
119 _cairo_error_throw (CAIRO_STATUS_NO_MEMORY
);
120 return (cairo_output_stream_t
*) &_cairo_output_stream_nil
;
123 _cairo_output_stream_init (&stream
->base
,
124 _cairo_base85_stream_write
,
126 _cairo_base85_stream_close
);
127 stream
->output
= output
;
130 return &stream
->base
;