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+/* lzw.h -- define the lzw functions.
+
+ Copyright (C) 1994-2016 Free Software Foundation, Inc.
+ Copyright (C) 1992-1993 Jean-loup Gailly.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+#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 compression 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 compression: 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 int lzw (int in, int out);
+extern int unlzw (int in, int out);