| /* infutil.h -- types and macros common to blocks and codes |
| * Copyright (C) 1995-1998 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 |
| |
| #include <linux/zconf.h> |
| #include "inftrees.h" |
| #include "infcodes.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 */ |
| B_DONE, /* finished last block, done */ |
| B_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) */ |
| uInt *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 */ |
| Byte *window; /* sliding window */ |
| Byte *end; /* one byte after sliding window */ |
| Byte *read; /* window read pointer */ |
| Byte *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 zlib_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=zlib_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 zlib_inflate_mask[17]; |
| |
| /* copy as much as possible from the sliding window to the output area */ |
| extern int zlib_inflate_flush ( |
| inflate_blocks_statef *, |
| z_streamp , |
| int); |
| |
| /* inflate private state */ |
| typedef enum { |
| METHOD, /* waiting for method byte */ |
| FLAG, /* waiting for flag byte */ |
| DICT4, /* four dictionary check bytes to go */ |
| DICT3, /* three dictionary check bytes to go */ |
| DICT2, /* two dictionary check bytes to go */ |
| DICT1, /* one dictionary check byte to go */ |
| DICT0, /* waiting for inflateSetDictionary */ |
| BLOCKS, /* decompressing blocks */ |
| CHECK4, /* four check bytes to go */ |
| CHECK3, /* three check bytes to go */ |
| CHECK2, /* two check bytes to go */ |
| CHECK1, /* one check byte to go */ |
| I_DONE, /* finished check, done */ |
| I_BAD} /* got an error--stay here */ |
| inflate_mode; |
| |
| struct internal_state { |
| |
| /* mode */ |
| inflate_mode mode; /* current inflate mode */ |
| |
| /* mode dependent information */ |
| union { |
| uInt method; /* if FLAGS, method byte */ |
| struct { |
| uLong was; /* computed check value */ |
| uLong need; /* stream check value */ |
| } check; /* if CHECK, check values to compare */ |
| uInt marker; /* if BAD, inflateSync's marker bytes count */ |
| } sub; /* submode */ |
| |
| /* mode independent information */ |
| int nowrap; /* flag for no wrapper */ |
| uInt wbits; /* log2(window size) (8..15, defaults to 15) */ |
| inflate_blocks_statef |
| *blocks; /* current inflate_blocks state */ |
| |
| }; |
| |
| /* inflate codes private state */ |
| typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ |
| START, /* x: set up for LEN */ |
| LEN, /* i: get length/literal/eob next */ |
| LENEXT, /* i: getting length extra (have base) */ |
| DIST, /* i: get distance next */ |
| DISTEXT, /* i: getting distance extra */ |
| COPY, /* o: copying bytes in window, waiting for space */ |
| LIT, /* o: got literal, waiting for output space */ |
| WASH, /* o: got eob, possibly still output waiting */ |
| END, /* x: got eob and all data flushed */ |
| BADCODE} /* x: got error */ |
| inflate_codes_mode; |
| |
| struct inflate_codes_state { |
| |
| /* mode */ |
| inflate_codes_mode mode; /* current inflate_codes mode */ |
| |
| /* mode dependent information */ |
| uInt len; |
| union { |
| struct { |
| inflate_huft *tree; /* pointer into tree */ |
| uInt need; /* bits needed */ |
| } code; /* if LEN or DIST, where in tree */ |
| uInt lit; /* if LIT, literal */ |
| struct { |
| uInt get; /* bits to get for extra */ |
| uInt dist; /* distance back to copy from */ |
| } copy; /* if EXT or COPY, where and how much */ |
| } sub; /* submode */ |
| |
| /* mode independent information */ |
| Byte lbits; /* ltree bits decoded per branch */ |
| Byte dbits; /* dtree bits decoder per branch */ |
| inflate_huft *ltree; /* literal/length/eob tree */ |
| inflate_huft *dtree; /* distance tree */ |
| |
| }; |
| |
| /* memory allocation for inflation */ |
| |
| struct inflate_workspace { |
| inflate_codes_statef working_state; |
| struct inflate_blocks_state working_blocks_state; |
| struct internal_state internal_state; |
| unsigned int tree_work_area_1[19]; |
| unsigned int tree_work_area_2[288]; |
| unsigned working_blens[258 + 0x1f + 0x1f]; |
| inflate_huft working_hufts[MANY]; |
| unsigned char working_window[1 << MAX_WBITS]; |
| }; |
| |
| #define WS(z) ((struct inflate_workspace *)(z->workspace)) |
| |
| #endif |