/* 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)<<k;k+=8;}} | |
#define DUMPBITS(j) {b>>=(j);k-=(j);} | |
/* output bytes */ | |
#define WAVAIL (uInt)(q<s->read?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++) */ | |
#ifndef NO_INFLATE_MASK | |
local uInt inflate_mask[17]; | |
#endif | |
/* copy as much as possible from the sliding window to the output area */ | |
local int inflate_flush OF(( | |
inflate_blocks_statef *, | |
z_streamp , | |
int)); | |
#endif |