SecurityServer/MacYarrow/zlib/infutil.h

   1 /*
   2  * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * The contents of this file constitute Original Code as defined in and are
   5  * subject to the Apple Public Source License Version 1.2 (the 'License').
   6  * You may not use this file except in compliance with the License. Please obtain
   7  * a copy of the License at http://www.apple.com/publicsource and read it before
   8  * using this file.
   9  *
  10  * This Original Code and all software distributed under the License are
  11  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
  12  * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
  13  * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
  14  * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
  15  * specific language governing rights and limitations under the License.
  16  */
  17
  18
  19 /* infutil.h -- types and macros common to blocks and codes
  20  * Copyright (C) 1995-1998 Mark Adler
  21  * For conditions of distribution and use, see copyright notice in zlib.h
  22  */
  23
  24 /* WARNING: this file should *not* be used by applications. It is
  25    part of the implementation of the compression library and is
  26    subject to change. Applications should only use zlib.h.
  27  */
  28
  29 #ifndef _INFUTIL_H
  30 #define _INFUTIL_H
  31
  32 typedef enum {
  33       TYPE,     /* get type bits (3, including end bit) */
  34       LENS,     /* get lengths for stored */
  35       STORED,   /* processing stored block */
  36       TABLE,    /* get table lengths */
  37       BTREE,    /* get bit lengths tree for a dynamic block */
  38       DTREE,    /* get length, distance trees for a dynamic block */
  39       CODES,    /* processing fixed or dynamic block */
  40       DRY,      /* output remaining window bytes */
  41       DONE,     /* finished last block, done */
  42       BAD}      /* got a data error--stuck here */
  43 inflate_block_mode;
  44
  45 /* inflate blocks semi-private state */
  46 struct inflate_blocks_state {
  47
  48   /* mode */
  49   inflate_block_mode  mode;     /* current inflate_block mode */
  50
  51   /* mode dependent information */
  52   union {
  53     uInt left;          /* if STORED, bytes left to copy */
  54     struct {
  55       uInt table;               /* table lengths (14 bits) */
  56       uInt index;               /* index into blens (or border) */
  57       uIntf *blens;             /* bit lengths of codes */
  58       uInt bb;                  /* bit length tree depth */
  59       inflate_huft *tb;         /* bit length decoding tree */
  60     } trees;            /* if DTREE, decoding info for trees */
  61     struct {
  62       inflate_codes_statef
  63          *codes;
  64     } decode;           /* if CODES, current state */
  65   } sub;                /* submode */
  66   uInt last;            /* true if this block is the last block */
  67
  68   /* mode independent information */
  69   uInt bitk;            /* bits in bit buffer */
  70   uLong bitb;           /* bit buffer */
  71   inflate_huft *hufts;  /* single malloc for tree space */
  72   Bytef *window;        /* sliding window */
  73   Bytef *end;           /* one byte after sliding window */
  74   Bytef *read;          /* window read pointer */
  75   Bytef *write;         /* window write pointer */
  76   check_func checkfn;   /* check function */
  77   uLong check;          /* check on output */
  78
  79 };
  80
  81
  82 /* defines for inflate input/output */
  83 /*   update pointers and return */
  84 #define UPDBITS {s->bitb=b;s->bitk=k;}
  85 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
  86 #define UPDOUT {s->write=q;}
  87 #define UPDATE {UPDBITS UPDIN UPDOUT}
  88 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
  89 /*   get bytes and bits */
  90 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
  91 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
  92 #define NEXTBYTE (n--,*p++)
  93 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
  94 #define DUMPBITS(j) {b>>=(j);k-=(j);}
  95 /*   output bytes */
  96 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
  97 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
  98 #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
  99 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
 100 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
 101 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
 102 /*   load local pointers */
 103 #define LOAD {LOADIN LOADOUT}
 104
 105 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */
 106 extern uInt inflate_mask[17];
 107
 108 /* copy as much as possible from the sliding window to the output area */
 109 extern int inflate_flush OF((
 110     inflate_blocks_statef *,
 111     z_streamp ,
 112     int));
 113
 114 struct internal_state      {int dummy;}; /* for buggy compilers */
 115
 116 #endif