0,0 → 1,131 |
/* -*- Mode: c; c-basic-offset: 4; indent-tabs-mode: t; tab-width: 8; -*- */ |
/* cairo - a vector graphics library with display and print output |
* |
* Copyright © 2005 Red Hat, Inc |
* |
* This library is free software; you can redistribute it and/or |
* modify it either under the terms of the GNU Lesser General Public |
* License version 2.1 as published by the Free Software Foundation |
* (the "LGPL") or, at your option, under the terms of the Mozilla |
* Public License Version 1.1 (the "MPL"). If you do not alter this |
* notice, a recipient may use your version of this file under either |
* the MPL or the LGPL. |
* |
* You should have received a copy of the LGPL along with this library |
* in the file COPYING-LGPL-2.1; if not, write to the Free Software |
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA |
* You should have received a copy of the MPL along with this library |
* in the file COPYING-MPL-1.1 |
* |
* The contents of this file are subject to the Mozilla Public License |
* Version 1.1 (the "License"); you may not use this file except in |
* compliance with the License. You may obtain a copy of the License at |
* http://www.mozilla.org/MPL/ |
* |
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY |
* OF ANY KIND, either express or implied. See the LGPL or the MPL for |
* the specific language governing rights and limitations. |
* |
* The Original Code is the cairo graphics library. |
* |
* The Initial Developer of the Original Code is Red Hat, Inc. |
* |
* Author(s): |
* Kristian Høgsberg <krh@redhat.com> |
*/ |
|
#include "cairoint.h" |
#include "cairo-error-private.h" |
#include "cairo-output-stream-private.h" |
|
typedef struct _cairo_base85_stream { |
cairo_output_stream_t base; |
cairo_output_stream_t *output; |
unsigned char four_tuple[4]; |
int pending; |
} cairo_base85_stream_t; |
|
static void |
_expand_four_tuple_to_five (unsigned char four_tuple[4], |
unsigned char five_tuple[5], |
cairo_bool_t *all_zero) |
{ |
uint32_t value; |
int digit, i; |
|
value = four_tuple[0] << 24 | four_tuple[1] << 16 | four_tuple[2] << 8 | four_tuple[3]; |
if (all_zero) |
*all_zero = TRUE; |
for (i = 0; i < 5; i++) { |
digit = value % 85; |
if (digit != 0 && all_zero) |
*all_zero = FALSE; |
five_tuple[4-i] = digit + 33; |
value = value / 85; |
} |
} |
|
static cairo_status_t |
_cairo_base85_stream_write (cairo_output_stream_t *base, |
const unsigned char *data, |
unsigned int length) |
{ |
cairo_base85_stream_t *stream = (cairo_base85_stream_t *) base; |
const unsigned char *ptr = data; |
unsigned char five_tuple[5]; |
cairo_bool_t is_zero; |
|
while (length) { |
stream->four_tuple[stream->pending++] = *ptr++; |
length--; |
if (stream->pending == 4) { |
_expand_four_tuple_to_five (stream->four_tuple, five_tuple, &is_zero); |
if (is_zero) |
_cairo_output_stream_write (stream->output, "z", 1); |
else |
_cairo_output_stream_write (stream->output, five_tuple, 5); |
stream->pending = 0; |
} |
} |
|
return _cairo_output_stream_get_status (stream->output); |
} |
|
static cairo_status_t |
_cairo_base85_stream_close (cairo_output_stream_t *base) |
{ |
cairo_base85_stream_t *stream = (cairo_base85_stream_t *) base; |
unsigned char five_tuple[5]; |
|
if (stream->pending) { |
memset (stream->four_tuple + stream->pending, 0, 4 - stream->pending); |
_expand_four_tuple_to_five (stream->four_tuple, five_tuple, NULL); |
_cairo_output_stream_write (stream->output, five_tuple, stream->pending + 1); |
} |
|
return _cairo_output_stream_get_status (stream->output); |
} |
|
cairo_output_stream_t * |
_cairo_base85_stream_create (cairo_output_stream_t *output) |
{ |
cairo_base85_stream_t *stream; |
|
if (output->status) |
return _cairo_output_stream_create_in_error (output->status); |
|
stream = malloc (sizeof (cairo_base85_stream_t)); |
if (unlikely (stream == NULL)) { |
_cairo_error_throw (CAIRO_STATUS_NO_MEMORY); |
return (cairo_output_stream_t *) &_cairo_output_stream_nil; |
} |
|
_cairo_output_stream_init (&stream->base, |
_cairo_base85_stream_write, |
NULL, |
_cairo_base85_stream_close); |
stream->output = output; |
stream->pending = 0; |
|
return &stream->base; |
} |