text: /* inflate.h -- internal inflate state definition
   * Copyright (C) 1995-2009 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.
   */
  
  /* define NO_GZIP when compiling if you want to disable gzip header and
     trailer decoding by inflate().  NO_GZIP would be used to avoid linking in
     the crc code when it is not needed.  For shared libraries, gzip decoding
     should be left enabled. */
  #ifndef NO_GZIP
  #  define GUNZIP
  #endif
  
  /* Possible inflate modes between inflate() calls */
  typedef enum {
      HEAD,       /* i: waiting for magic header */
      FLAGS,      /* i: waiting for method and flags (gzip) */
      TIME,       /* i: waiting for modification time (gzip) */
      OS,         /* i: waiting for extra flags and operating system (gzip) */
      EXLEN,      /* i: waiting for extra length (gzip) */
      EXTRA,      /* i: waiting for extra bytes (gzip) */
      NAME,       /* i: waiting for end of file name (gzip) */
      COMMENT,    /* i: waiting for end of comment (gzip) */
      HCRC,       /* i: waiting for header crc (gzip) */
      DICTID,     /* i: waiting for dictionary check value */
      DICT,       /* waiting for inflateSetDictionary() call */
          TYPE,       /* i: waiting for type bits, including last-flag bit */
          TYPEDO,     /* i: same, but skip check to exit inflate on new block */
          STORED,     /* i: waiting for stored size (length and complement) */
          COPY_,      /* i/o: same as COPY below, but only first time in */
          COPY,       /* i/o: waiting for input or output to copy stored block */
          TABLE,      /* i: waiting for dynamic block table lengths */
          LENLENS,    /* i: waiting for code length code lengths */
          CODELENS,   /* i: waiting for length/lit and distance code lengths */
              LEN_,       /* i: same as LEN below, but only first time in */
              LEN,        /* i: waiting for length/lit/eob code */
              LENEXT,     /* i: waiting for length extra bits */
              DIST,       /* i: waiting for distance code */
              DISTEXT,    /* i: waiting for distance extra bits */
              MATCH,      /* o: waiting for output space to copy string */
              LIT,        /* o: waiting for output space to write literal */
      CHECK,      /* i: waiting for 32-bit check value */
      LENGTH,     /* i: waiting for 32-bit length (gzip) */
      DONE,       /* finished check, done -- remain here until reset */
      BAD,        /* got a data error -- remain here until reset */
      MEM,        /* got an inflate() memory error -- remain here until reset */
      SYNC        /* looking for synchronization bytes to restart inflate() */
  } inflate_mode;
  
  /*
      State transitions between above modes -
  
      (most modes can go to BAD or MEM on error -- not shown for clarity)
  
      Process header:
          HEAD -> (gzip) or (zlib) or (raw)
          (gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME -> COMMENT ->
                    HCRC -> TYPE
          (zlib) -> DICTID or TYPE
          DICTID -> DICT -> TYPE
          (raw) -> TYPEDO
      Read deflate blocks:
              TYPE -> TYPEDO -> STORED or TABLE or LEN_ or CHECK
              STORED -> COPY_ -> COPY -> TYPE
              TABLE -> LENLENS -> CODELENS -> LEN_
              LEN_ -> LEN
      Read deflate codes in fixed or dynamic block:
                  LEN -> LENEXT or LIT or TYPE
                  LENEXT -> DIST -> DISTEXT -> MATCH -> LEN
                  LIT -> LEN
      Process trailer:
          CHECK -> LENGTH -> DONE
   */
  
  /* state maintained between inflate() calls.  Approximately 10K bytes. */
  struct inflate_state {
      inflate_mode mode;          /* current inflate mode */
      int last;                   /* true if processing last block */
      int wrap;                   /* bit 0 true for zlib, bit 1 true for gzip */
      int havedict;               /* true if dictionary provided */
      int flags;                  /* gzip header method and flags (0 if zlib) */
      unsigned dmax;              /* zlib header max distance (INFLATE_STRICT) */
      unsigned long check;        /* protected copy of check value */
      unsigned long total;        /* protected copy of output count */
      gz_headerp head;            /* where to save gzip header information */
          /* sliding window */
      unsigned wbits;             /* log base 2 of requested window size */
      unsigned wsize;             /* window size or zero if not using window */
      unsigned whave;             /* valid bytes in the window */
      unsigned wnext;             /* window write index */
      unsigned char FAR *window;  /* allocated sliding window, if needed */
          /* bit accumulator */
      unsigned long hold;         /* input bit accumulator */
      unsigned bits;              /* number of bits in "in" */
          /* for string and stored block copying */
      unsigned length;            /* literal or length of data to copy */
      unsigned offset;            /* distance back to copy string from */
          /* for table and code decoding */
      unsigned extra;             /* extra bits needed */
          /* fixed and dynamic code tables */
      code const FAR *lencode;    /* starting table for length/literal codes */
      code const FAR *distcode;   /* starting table for distance codes */
      unsigned lenbits;           /* index bits for lencode */
      unsigned distbits;          /* index bits for distcode */
          /* dynamic table building */
      unsigned ncode;             /* number of code length code lengths */
      unsigned nlen;              /* number of length code lengths */
      unsigned ndist;             /* number of distance code lengths */
      unsigned have;              /* number of code lengths in lens[] */
      code FAR *next;             /* next available space in codes[] */
      unsigned short lens[320];   /* temporary storage for code lengths */
      unsigned short work[288];   /* work area for code table building */
      code codes[ENOUGH];         /* space for code tables */
      int sane;                   /* if false, allow invalid distance too far */
      int back;                   /* bits back of last unprocessed length/lit */
      unsigned was;               /* initial length of match */
  };
  