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Diffstat (limited to 'src/cairo-deflate-stream.c')
| -rwxr-xr-x | src/cairo-deflate-stream.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/src/cairo-deflate-stream.c b/src/cairo-deflate-stream.c new file mode 100755 index 000000000..ae23bda94 --- /dev/null +++ b/src/cairo-deflate-stream.c @@ -0,0 +1,156 @@ +/* -*- Mode: c; c-basic-offset: 4; indent-tabs-mode: t; tab-width: 8; -*- */ +/* cairo - a vector graphics library with display and print output + * + * Copyright © 2006 Adrian Johnson + * + * 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 Adrian Johnson. + * + * Author(s): + * Adrian Johnson <ajohnson@redneon.com> + */ + +#include "cairoint.h" + +#if CAIRO_HAS_DEFLATE_STREAM + +#include "cairo-error-private.h" +#include "cairo-output-stream-private.h" +#include <zlib.h> + +#define BUFFER_SIZE 16384 + +typedef struct _cairo_deflate_stream { + cairo_output_stream_t base; + cairo_output_stream_t *output; + z_stream zlib_stream; + unsigned char input_buf[BUFFER_SIZE]; + unsigned char output_buf[BUFFER_SIZE]; +} cairo_deflate_stream_t; + +static void +cairo_deflate_stream_deflate (cairo_deflate_stream_t *stream, cairo_bool_t flush) +{ + int ret; + cairo_bool_t finished; + + do { + ret = deflate (&stream->zlib_stream, flush ? Z_FINISH : Z_NO_FLUSH); + if (flush || stream->zlib_stream.avail_out == 0) + { + _cairo_output_stream_write (stream->output, + stream->output_buf, + BUFFER_SIZE - stream->zlib_stream.avail_out); + stream->zlib_stream.next_out = stream->output_buf; + stream->zlib_stream.avail_out = BUFFER_SIZE; + } + + finished = TRUE; + if (stream->zlib_stream.avail_in != 0) + finished = FALSE; + if (flush && ret != Z_STREAM_END) + finished = FALSE; + + } while (!finished); + + stream->zlib_stream.next_in = stream->input_buf; +} + +static cairo_status_t +_cairo_deflate_stream_write (cairo_output_stream_t *base, + const unsigned char *data, + unsigned int length) +{ + cairo_deflate_stream_t *stream = (cairo_deflate_stream_t *) base; + unsigned int count; + const unsigned char *p = data; + + while (length) { + count = length; + if (count > BUFFER_SIZE - stream->zlib_stream.avail_in) + count = BUFFER_SIZE - stream->zlib_stream.avail_in; + memcpy (stream->input_buf + stream->zlib_stream.avail_in, p, count); + p += count; + stream->zlib_stream.avail_in += count; + length -= count; + + if (stream->zlib_stream.avail_in == BUFFER_SIZE) + cairo_deflate_stream_deflate (stream, FALSE); + } + + return _cairo_output_stream_get_status (stream->output); +} + +static cairo_status_t +_cairo_deflate_stream_close (cairo_output_stream_t *base) +{ + cairo_deflate_stream_t *stream = (cairo_deflate_stream_t *) base; + + cairo_deflate_stream_deflate (stream, TRUE); + deflateEnd (&stream->zlib_stream); + + return _cairo_output_stream_get_status (stream->output); +} + +cairo_output_stream_t * +_cairo_deflate_stream_create (cairo_output_stream_t *output) +{ + cairo_deflate_stream_t *stream; + + if (output->status) + return _cairo_output_stream_create_in_error (output->status); + + stream = malloc (sizeof (cairo_deflate_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_deflate_stream_write, + NULL, + _cairo_deflate_stream_close); + stream->output = output; + + stream->zlib_stream.zalloc = Z_NULL; + stream->zlib_stream.zfree = Z_NULL; + stream->zlib_stream.opaque = Z_NULL; + + if (deflateInit (&stream->zlib_stream, Z_DEFAULT_COMPRESSION) != Z_OK) { + free (stream); + return (cairo_output_stream_t *) &_cairo_output_stream_nil; + } + + stream->zlib_stream.next_in = stream->input_buf; + stream->zlib_stream.avail_in = 0; + stream->zlib_stream.next_out = stream->output_buf; + stream->zlib_stream.avail_out = BUFFER_SIZE; + + return &stream->base; +} + +#endif /* CAIRO_HAS_DEFLATE_STREAM */ |