/* lzw.h -- define the lzw functions. * Copyright (C) 1992-1993 Jean-loup Gailly. * This is free software; you can redistribute it and/or modify it under the * terms of the GNU General Public License, see the file COPYING. */#if !defined(OF) && defined(lint)#  include "gzip.h"#endif#ifndef BITS#  define BITS 16#endif#define INIT_BITS 9              /* Initial number of bits per code */#define	LZW_MAGIC  "\037\235"   /* Magic header for lzw files, 1F 9D */#define BIT_MASK    0x1f /* Mask for 'number of compresssion bits' *//* Mask 0x20 is reserved to mean a fourth header byte, and 0x40 is free. * It's a pity that old uncompress does not check bit 0x20. That makes * extension of the format actually undesirable because old compress * would just crash on the new format instead of giving a meaningful * error message. It does check the number of bits, but it's more * helpful to say "unsupported format, get a new version" than * "can only handle 16 bits". */#define BLOCK_MODE  0x80/* Block compresssion: if table is full and compression rate is dropping, * clear the dictionary. */#define LZW_RESERVED 0x60 /* reserved bits */#define	CLEAR  256       /* flush the dictionary */#define FIRST  (CLEAR+1) /* first free entry */extern int maxbits;      /* max bits per code for LZW */extern int block_mode;   /* block compress mode -C compatible with 2.0 */extern void lzw    OF((int in, int out));extern void unlzw  OF((int in, int out));