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/* infutil.h -- types and macros common to blocks and codes
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 * Copyright (C) 1995-2002 Mark Adler
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 * For conditions of distribution and use, see copyright notice in zlib.h
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 */
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/* WARNING: this file should *not* be used by applications. It is
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   part of the implementation of the compression library and is
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   subject to change. Applications should only use zlib.h.
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 */
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#ifndef _INFUTIL_H
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#define _INFUTIL_H
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typedef enum {
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      TYPE,     /* get type bits (3, including end bit) */
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      LENS,     /* get lengths for stored */
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      STORED,   /* processing stored block */
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      TABLE,    /* get table lengths */
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      BTREE,    /* get bit lengths tree for a dynamic block */
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      DTREE,    /* get length, distance trees for a dynamic block */
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      CODES,    /* processing fixed or dynamic block */
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      DRY,      /* output remaining window bytes */
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      DONE,     /* finished last block, done */
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      BAD}      /* got a data error--stuck here */
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inflate_block_mode;
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/* inflate blocks semi-private state */
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struct inflate_blocks_state {
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  /* mode */
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  inflate_block_mode  mode;     /* current inflate_block mode */
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  /* mode dependent information */
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  union {
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    uInt left;          /* if STORED, bytes left to copy */
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    struct {
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      uInt table;               /* table lengths (14 bits) */
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      uInt index;               /* index into blens (or border) */
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      uIntf *blens;             /* bit lengths of codes */
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      uInt bb;                  /* bit length tree depth */
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      inflate_huft *tb;         /* bit length decoding tree */
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    } trees;            /* if DTREE, decoding info for trees */
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    struct {
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      inflate_codes_statef
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         *codes;
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    } decode;           /* if CODES, current state */
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  } sub;                /* submode */
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  uInt last;            /* true if this block is the last block */
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  /* mode independent information */
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  uInt bitk;            /* bits in bit buffer */
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  uLong bitb;           /* bit buffer */
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  inflate_huft *hufts;  /* single malloc for tree space */
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  Bytef *window;        /* sliding window */
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  Bytef *end;           /* one byte after sliding window */
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  Bytef *read;          /* window read pointer */
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  Bytef *write;         /* window write pointer */
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  check_func checkfn;   /* check function */
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  uLong check;          /* check on output */
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};
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/* defines for inflate input/output */
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/*   update pointers and return */
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#define UPDBITS {s->bitb=b;s->bitk=k;}
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#define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
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#define UPDOUT {s->write=q;}
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#define UPDATE {UPDBITS UPDIN UPDOUT}
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#define LEAVE {UPDATE return inflate_flush(s,z,r);}
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/*   get bytes and bits */
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#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
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#define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
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#define NEXTBYTE (n--,*p++)
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#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
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#define DUMPBITS(j) {b>>=(j);k-=(j);}
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/*   output bytes */
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#define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
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#define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
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#define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
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#define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
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#define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
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#define OUTBYTE(a) {*q++=(Byte)(a);m--;}
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/*   load local pointers */
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#define LOAD {LOADIN LOADOUT}
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/* masks for lower bits (size given to avoid silly warnings with Visual C++) */
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extern uInt inflate_mask[17];
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/* copy as much as possible from the sliding window to the output area */
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extern int inflate_flush OF((
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    inflate_blocks_statef *,
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    z_streamp ,
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    int));
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struct internal_state      {int dummy;}; /* for buggy compilers */
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#endif