| /* compress.c -- compress a memory buffer |
| * Copyright (C) 1995-1996 Jean-loup Gailly. |
| * For conditions of distribution and use, see copyright notice in zlib.h |
| */ |
| |
| /* $Id: compress.c,v 1.9 1996/01/30 21:59:09 me 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) |
| Bytef *dest; |
| uLongf *destLen; |
| const Bytef *source; |
| uLong sourceLen; |
| { |
| z_stream stream; |
| int err; |
| |
| stream.next_in = (Bytef*)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; |
| stream.opaque = (voidpf)0; |
| |
| err = deflateInit(&stream, Z_DEFAULT_COMPRESSION); |
| 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; |
| } |