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author | dkf <donal.k.fellows@manchester.ac.uk> | 2008-12-18 14:14:59 (GMT) |
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committer | dkf <donal.k.fellows@manchester.ac.uk> | 2008-12-18 14:14:59 (GMT) |
commit | 7b022824ad2bf092e5142967198fc52a0baa4b32 (patch) | |
tree | e7ce199f58cd0d8a550fd370e9bc7278582b52cf /compat/zlib/compress.c | |
parent | 374bd78bd6abe396658c2f4cab41ff8c61fa730c (diff) | |
download | tcl-7b022824ad2bf092e5142967198fc52a0baa4b32.zip tcl-7b022824ad2bf092e5142967198fc52a0baa4b32.tar.gz tcl-7b022824ad2bf092e5142967198fc52a0baa4b32.tar.bz2 |
Import of zlib 1.2.3
Diffstat (limited to 'compat/zlib/compress.c')
-rw-r--r-- | compat/zlib/compress.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/compat/zlib/compress.c b/compat/zlib/compress.c new file mode 100644 index 0000000..6f3eac1 --- /dev/null +++ b/compat/zlib/compress.c @@ -0,0 +1,79 @@ +/* compress.c -- compress a memory buffer + * Copyright (C) 1995-2003 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* @(#) $Id: compress.c,v 1.1 2008/12/18 14:14:59 dkf Exp $ */ + +#define ZLIB_INTERNAL +#include "zlib.h" + +/* =========================================================================== + Compresses the source buffer into the destination buffer. The level + parameter has the same meaning as in deflateInit. sourceLen is the byte + length of the source buffer. Upon entry, destLen is the total size of the + destination buffer, which must be at least 0.1% larger than sourceLen plus + 12 bytes. Upon exit, destLen is the actual size of the compressed buffer. + + compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough + memory, Z_BUF_ERROR if there was not enough room in the output buffer, + Z_STREAM_ERROR if the level parameter is invalid. +*/ +int ZEXPORT compress2 (dest, destLen, source, sourceLen, level) + Bytef *dest; + uLongf *destLen; + const Bytef *source; + uLong sourceLen; + int level; +{ + z_stream stream; + int err; + + stream.next_in = (Bytef*)source; + stream.avail_in = (uInt)sourceLen; +#ifdef MAXSEG_64K + /* Check for source > 64K on 16-bit machine: */ + if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR; +#endif + stream.next_out = dest; + stream.avail_out = (uInt)*destLen; + if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR; + + stream.zalloc = (alloc_func)0; + stream.zfree = (free_func)0; + stream.opaque = (voidpf)0; + + err = deflateInit(&stream, level); + if (err != Z_OK) return err; + + err = deflate(&stream, Z_FINISH); + if (err != Z_STREAM_END) { + deflateEnd(&stream); + return err == Z_OK ? Z_BUF_ERROR : err; + } + *destLen = stream.total_out; + + err = deflateEnd(&stream); + return err; +} + +/* =========================================================================== + */ +int ZEXPORT compress (dest, destLen, source, sourceLen) + Bytef *dest; + uLongf *destLen; + const Bytef *source; + uLong sourceLen; +{ + return compress2(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION); +} + +/* =========================================================================== + If the default memLevel or windowBits for deflateInit() is changed, then + this function needs to be updated. + */ +uLong ZEXPORT compressBound (sourceLen) + uLong sourceLen; +{ + return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) + 11; +} |