Mercurial > mm7

comparison lib/zlib/compress.c @ 0:9c0607679772

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
init
author Ritor1
date Sat, 12 Jan 2013 09:45:18 +0600
parents
children
comparison
equal deleted inserted replaced
-1:000000000000 0:9c0607679772
1 /* compress.c -- compress a memory buffer
2 * Copyright (C) 1995-1998 Jean-loup Gailly.
3 * For conditions of distribution and use, see copyright notice in zlib.h
4 */
5
6 /* @(#) $Id$ */
7
8 #include "zlib.h"
9
10 /* ===========================================================================
11 Compresses the source buffer into the destination buffer. The level
12 parameter has the same meaning as in deflateInit. sourceLen is the byte
13 length of the source buffer. Upon entry, destLen is the total size of the
14 destination buffer, which must be at least 0.1% larger than sourceLen plus
15 12 bytes. Upon exit, destLen is the actual size of the compressed buffer.
16
17 compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
18 memory, Z_BUF_ERROR if there was not enough room in the output buffer,
19 Z_STREAM_ERROR if the level parameter is invalid.
20 */
21 int ZEXPORT compress2 (dest, destLen, source, sourceLen, level)
22 Bytef *dest;
23 uLongf *destLen;
24 const Bytef *source;
25 uLong sourceLen;
26 int level;
27 {
28 z_stream stream;
29 int err;
30
31 stream.next_in = (Bytef*)source;
32 stream.avail_in = (uInt)sourceLen;
33 #ifdef MAXSEG_64K
34 /* Check for source > 64K on 16-bit machine: */
35 if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
36 #endif
37 stream.next_out = dest;
38 stream.avail_out = (uInt)*destLen;
39 if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
40
41 stream.zalloc = (alloc_func)0;
42 stream.zfree = (free_func)0;
43 stream.opaque = (voidpf)0;
44
45 err = deflateInit(&stream, level);
46 if (err != Z_OK) return err;
47
48 err = deflate(&stream, Z_FINISH);
49 if (err != Z_STREAM_END) {
50 deflateEnd(&stream);
51 return err == Z_OK ? Z_BUF_ERROR : err;
52 }
53 *destLen = stream.total_out;
54
55 err = deflateEnd(&stream);
56 return err;
57 }
58
59 /* ===========================================================================
60 */
61 int ZEXPORT compress (dest, destLen, source, sourceLen)
62 Bytef *dest;
63 uLongf *destLen;
64 const Bytef *source;
65 uLong sourceLen;
66 {
67 return compress2(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION);
68 }