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/*
 * Copyright (C) 1995-2002 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h 
 */

/**
 * \file inftrees.h
 * Header to use inftrees.c.
 */

/* 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.
 */

/* Huffman code lookup table entry--this entry is four bytes for machines
   that have 16-bit pointers (e.g. PC's in the small or medium model). */

typedef struct inflate_huft_s FAR inflate_huft;

struct inflate_huft_s {
  union {
    struct {
      Byte Exop;        /*!< number of extra bits or operation */
      Byte Bits;        /*!< number of bits in this code or subcode */
    } what;
    uInt pad;           /*!< pad structure to a power of 2 (4 bytes for */
  } word;               /*!<  16-bit, 8 bytes for 32-bit int's) */
  uInt base;            /*!< literal, length base, distance base,
                           or table offset */
};

/**
 * Maximum size of dynamic tree.  The maximum found in a long but non-
 * exhaustive search was 1004 huft structures (850 for length/literals
 * and 154 for distances, the latter actually the result of an
 * exhaustive search).  The actual maximum is not known, but the
 * value below is more than safe.
 */
#define MANY 1440

extern int inflate_trees_bits OF((
    uIntf * c,                  /* 19 code lengths */
    uIntf * bb,                 /* bits tree desired/actual depth */
    inflate_huft * FAR * tb,    /* bits tree result */
    inflate_huft * hp,          /* space for trees */
    z_streamp z));              /* for messages */

extern int inflate_trees_dynamic OF((
    uInt nl,                    /* number of literal/length codes */
    uInt nd,                    /* number of distance codes */
    uIntf * c,                  /* that many (total) code lengths */
    uIntf * bl,                 /* literal desired/actual bit depth */
    uIntf * bd,                 /* distance desired/actual bit depth */
    inflate_huft * FAR * tl,    /* literal/length tree result */
    inflate_huft * FAR * td,    /* distance tree result */
    inflate_huft * hp,          /* space for trees */
    z_streamp z));              /* for messages */

extern int inflate_trees_fixed OF((
    uIntf * bl,                 /* literal desired/actual bit depth */
    uIntf * bd,                 /* distance desired/actual bit depth */
    inflate_huft * FAR * tl,    /* literal/length tree result */
    inflate_huft * FAR * td,    /* distance tree result */
    z_streamp z));              /* for memory allocation */