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/* inftrees.h -- header to use inftrees.c

 * Copyright (C) 1995-2005 Mark Adler

 * For conditions of distribution and use, see copyright notice in zlib.h

 */

/* WARNING: this file should *not* be used by applications. It is

   part of the implementation of the compression library and is

   subject to change. Applications should only use zlib.h.

 */

/* Structure for decoding tables.  Each entry provides either the

   information needed to do the operation requested by the code that

   indexed that table entry, or it provides a pointer to another

   table that indexes more bits of the code.  op indicates whether

   the entry is a pointer to another table, a literal, a length or

   distance, an end-of-block, or an invalid code.  For a table

   pointer, the low four bits of op is the number of index bits of

   that table.  For a length or distance, the low four bits of op

   is the number of extra bits to get after the code.  bits is

   the number of bits in this code or part of the code to drop off

   of the bit buffer.  val is the actual byte to output in the case

   of a literal, the base length or distance, or the offset from

   the current table to the next table.  Each entry is four bytes. */

typedef struct {

    unsigned char op;           /* operation, extra bits, table bits */

    unsigned char bits;         /* bits in this part of the code */

    unsigned short val;         /* offset in table or code value */

} code;

/* op values as set by inflate_table():

    00000000 - literal

    0000tttt - table link, tttt != 0 is the number of table index bits

    0001eeee - length or distance, eeee is the number of extra bits

    01100000 - end of block

    01000000 - invalid code

 */

/* Maximum size of dynamic tree.  The maximum found in a long but non-

   exhaustive search was 1444 code structures (852 for length/literals

   and 592 for distances, the latter actually the result of an

   exhaustive search).  The true maximum is not known, but the value

   below is more than safe. */

#define ENOUGH 2048

#define MAXD 592

/* Type of code to build for inftable() */

typedef enum {

    CODES,

    LENS,

    DISTS

} codetype;

extern int inflate_table OF((codetype type, unsigned short FAR *lens,

                             unsigned codes, code FAR * FAR *table,

                             unsigned FAR *bits, unsigned short FAR *work));