www.pudn.com > zlibsource.zip > infutil.h

/* infutil.h -- types and macros common to blocks and codes 
 * Copyright (C) 1995-2002 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. 
 */ 
 
#ifndef _INFUTIL_H 
#define _INFUTIL_H 
 
typedef enum { 
      TYPE,     /* get type bits (3, including end bit) */ 
      LENS,     /* get lengths for stored */ 
      STORED,   /* processing stored block */ 
      TABLE,    /* get table lengths */ 
      BTREE,    /* get bit lengths tree for a dynamic block */ 
      DTREE,    /* get length, distance trees for a dynamic block */ 
      CODES,    /* processing fixed or dynamic block */ 
      DRY,      /* output remaining window bytes */ 
      DONE,     /* finished last block, done */ 
      BAD}      /* got a data error--stuck here */ 
inflate_block_mode; 
 
/* inflate blocks semi-private state */ 
struct inflate_blocks_state { 
 
  /* mode */ 
  inflate_block_mode  mode;     /* current inflate_block mode */ 
 
  /* mode dependent information */ 
  union { 
    uInt left;          /* if STORED, bytes left to copy */ 
    struct { 
      uInt table;               /* table lengths (14 bits) */ 
      uInt index;               /* index into blens (or border) */ 
      uIntf *blens;             /* bit lengths of codes */ 
      uInt bb;                  /* bit length tree depth */ 
      inflate_huft *tb;         /* bit length decoding tree */ 
    } trees;            /* if DTREE, decoding info for trees */ 
    struct { 
      inflate_codes_statef  
         *codes; 
    } decode;           /* if CODES, current state */ 
  } sub;                /* submode */ 
  uInt last;            /* true if this block is the last block */ 
 
  /* mode independent information */ 
  uInt bitk;            /* bits in bit buffer */ 
  uLong bitb;           /* bit buffer */ 
  inflate_huft *hufts;  /* single malloc for tree space */ 
  Bytef *window;        /* sliding window */ 
  Bytef *end;           /* one byte after sliding window */ 
  Bytef *read;          /* window read pointer */ 
  Bytef *write;         /* window write pointer */ 
  check_func checkfn;   /* check function */ 
  uLong check;          /* check on output */ 
 
}; 
 
 
/* defines for inflate input/output */ 
/*   update pointers and return */ 
#define UPDBITS {s->bitb=b;s->bitk=k;} 
#define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;} 
#define UPDOUT {s->write=q;} 
#define UPDATE {UPDBITS UPDIN UPDOUT} 
#define LEAVE {UPDATE return inflate_flush(s,z,r);} 
/*   get bytes and bits */ 
#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;} 
#define NEEDBYTE {if(n)r=Z_OK;else LEAVE} 
#define NEXTBYTE (n--,*p++) 
#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<>=(j);k-=(j);} 
/*   output bytes */ 
#define WAVAIL (uInt)(qread?s->read-q-1:s->end-q) 
#define LOADOUT {q=s->write;m=(uInt)WAVAIL;} 
#define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}} 
#define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT} 
#define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;} 
#define OUTBYTE(a) {*q++=(Byte)(a);m--;} 
/*   load local pointers */ 
#define LOAD {LOADIN LOADOUT} 
 
/* masks for lower bits (size given to avoid silly warnings with Visual C++) */ 
extern uInt inflate_mask[17]; 
 
/* copy as much as possible from the sliding window to the output area */ 
extern int inflate_flush OF(( 
    inflate_blocks_statef *, 
    z_streamp , 
    int)); 
 
struct internal_state      {int dummy;}; /* for buggy compilers */ 
 
#endif