1 /* infutil.h -- types and macros common to blocks and codes 2 * Copyright (C) 1995-2002 Mark Adler 3 * For conditions of distribution and use, see copyright notice in zlib.h 4 */ 5 6 /* WARNING: this file should *not* be used by applications. It is 7 part of the implementation of the compression library and is 8 subject to change. Applications should only use zlib.h. 9 */ 10 11 #ifndef _INFUTIL_H 12 #define _INFUTIL_H 13 14 typedef enum { 15 TYPE, /* get type bits (3, including end bit) */ 16 LENS, /* get lengths for stored */ 17 STORED, /* processing stored block */ 18 TABLE, /* get table lengths */ 19 BTREE, /* get bit lengths tree for a dynamic block */ 20 DTREE, /* get length, distance trees for a dynamic block */ 21 CODES, /* processing fixed or dynamic block */ 22 DRY, /* output remaining window bytes */ 23 DONE, /* finished last block, done */ 24 BAD} /* got a data error--stuck here */ 25 inflate_block_mode; 26 27 /* inflate blocks semi-private state */ 28 struct inflate_blocks_state { 29 30 /* mode */ 31 inflate_block_mode mode; /* current inflate_block mode */ 32 33 /* mode dependent information */ 34 union { 35 uInt left; /* if STORED, bytes left to copy */ 36 struct { 37 uInt table; /* table lengths (14 bits) */ 38 uInt index; /* index into blens (or border) */ 39 uIntf *blens; /* bit lengths of codes */ 40 uInt bb; /* bit length tree depth */ 41 inflate_huft *tb; /* bit length decoding tree */ 42 } trees; /* if DTREE, decoding info for trees */ 43 struct { 44 inflate_codes_statef 45 *codes; 46 } decode; /* if CODES, current state */ 47 } sub; /* submode */ 48 uInt last; /* true if this block is the last block */ 49 50 /* mode independent information */ 51 uInt bitk; /* bits in bit buffer */ 52 uLong bitb; /* bit buffer */ 53 inflate_huft *hufts; /* single malloc for tree space */ 54 Bytef *window; /* sliding window */ 55 Bytef *end; /* one byte after sliding window */ 56 Bytef *read; /* window read pointer */ 57 Bytef *write; /* window write pointer */ 58 check_func checkfn; /* check function */ 59 uLong check; /* check on output */ 60 61 }; 62 63 64 /* defines for inflate input/output */ 65 /* update pointers and return */ 66 #define UPDBITS {s->bitb=b;s->bitk=k;} 67 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;} 68 #define UPDOUT {s->write=q;} 69 #define UPDATE {UPDBITS UPDIN UPDOUT} 70 #define LEAVE {UPDATE return inflate_flush(s,z,r);} 71 /* get bytes and bits */ 72 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;} 73 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE} 74 #define NEXTBYTE (n--,*p++) 75 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}} 76 #define DUMPBITS(j) {b>>=(j);k-=(j);} 77 /* output bytes */ 78 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q) 79 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;} 80 #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}} 81 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT} 82 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;} 83 #define OUTBYTE(a) {*q++=(Byte)(a);m--;} 84 /* load local pointers */ 85 #define LOAD {LOADIN LOADOUT} 86 87 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */ 88 #ifndef NO_INFLATE_MASK 89 local uInt inflate_mask[17]; 90 #endif 91 92 /* copy as much as possible from the sliding window to the output area */ 93 local int inflate_flush OF(( 94 inflate_blocks_statef *, 95 z_streamp , 96 int)); 97 98 #endif 99
