Descent3/unzip/infutil.h
2024-04-16 12:56:40 -06:00

172 lines
10 KiB
C

/*
* $Logfile: /DescentIII/Main/unzip/infutil.h $
* $Revision: 2 $
* $Date: 8/13/99 8:01p $
* $Author: Jeff $
*
* <insert description of file here>
*
* $Log: /DescentIII/Main/unzip/infutil.h $
*
* 2 8/13/99 8:01p Jeff
* initial creation of zip class
*
* $NoKeywords: $
*/
/* 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
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++) */
extern uInt inflate_mask[17];
/* copy as much as possible from the sliding window to the output area */
extern int inflate_flush OF((inflate_blocks_statef *, z_streamp, int));
struct internal_state {
int dummy;
}; /* for buggy compilers */
#endif