Subversion Repositories shark

Rev

Rev 107 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
107 pj 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
extern uInt inflate_mask[17];
89
 
90
/* copy as much as possible from the sliding window to the output area */
91
extern int inflate_flush OF((
92
    inflate_blocks_statef *,
93
    z_streamp ,
94
    int));
95
 
96
struct internal_state      {int dummy;}; /* for buggy compilers */
97
 
98
#endif