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author | Mark Adler <madler@alumni.caltech.edu> | 2011-09-09 22:36:31 -0700 |
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committer | Mark Adler <madler@alumni.caltech.edu> | 2011-09-09 22:36:31 -0700 |
commit | bcf78a20978d76f64b7cd46d1a4d7a79a578c77b (patch) | |
tree | 1929db4ad12c15efc15ac123264a8a9046903a7a /compress.c | |
download | zlib-bcf78a20978d76f64b7cd46d1a4d7a79a578c77b.tar.gz |
zlib 0.71v0.71
Diffstat (limited to 'compress.c')
-rw-r--r-- | compress.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/compress.c b/compress.c new file mode 100644 index 0000000..8edcb2a --- /dev/null +++ b/compress.c @@ -0,0 +1,55 @@ +/* compress.c -- compress a memory buffer + * Copyright (C) 1995 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* $Id: compress.c,v 1.4 1995/04/10 15:52:04 jloup Exp $ */ + +#include "zlib.h" + +/* =========================================================================== + Compresses the source buffer into the destination buffer. 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 8 bytes. Upon exit, destLen is the actual size of the + compressed buffer. + This function can be used to compress a whole file at once if the + input file is mmap'ed. + compress 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. +*/ +int compress (dest, destLen, source, sourceLen) + Byte *dest; + uLong *destLen; + Byte *source; + uLong sourceLen; +{ + z_stream stream; + int err; + + stream.next_in = source; + stream.avail_in = (uInt)sourceLen; + /* Check for source > 64K on 16-bit machine: */ + if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR; + + 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; + + err = deflateInit(&stream, Z_DEFAULT_COMPRESSION); + if (err != Z_OK) return err; + + err = deflate(&stream, Z_FINISH); + if (err != Z_OK) { + deflateEnd(&stream); + return err; + } + *destLen = stream.total_out; + + err = deflateEnd(&stream); + return err; +} |