/* inftrees.h -- header to use inftrees.c

* Copyright (C) 1995-2003 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.

*/

/* Structure for decoding tables. Each entry provides either the

information needed to do the operation requested by the code that

indexed that table entry, or it provides a pointer to another

table that indexes more bits of the code. op indicates whether

the entry is a pointer to another table, a literal, a length or

distance, an end-of-block, or an invalid code. For a table

pointer, the low four bits of op is the number of index bits of

that table. For a length or distance, the low four bits of op

is the number of extra bits to get after the code. bits is

the number of bits in this code or part of the code to drop off

of the bit buffer. val is the actual byte to output in the case

of a literal, the base length or distance, or the offset from

the current table to the next table. Each entry is four bytes. */

typedef struct {

unsigned char op; /* operation, extra bits, table bits */

unsigned char bits; /* bits in this part of the code */

unsigned short val; /* offset in table or code value */

} code;

/* op values as set by inflate_table():

00000000 - literal

0000tttt - table link, tttt != 0 is the number of table index bits

0001eeee - length or distance, eeee is the number of extra bits

01100000 - end of block

01000000 - invalid code

*/

/* Maximum size of dynamic tree. The maximum found in a long but non-

exhaustive search was 1004 code structures (850 for length/literals

and 154 for distances, the latter actually the result of an

exhaustive search). The true maximum is not known, but the value

below is more than safe. */

#define ENOUGH 1440

#define MAXD 154

/* Type of code to build for inftable() */

typedef enum {

CODES,

LENS,

DISTS

} codetype;

extern int inflate_table OF((codetype type, unsigned short FAR *lens,

unsigned codes, code FAR * FAR *table,

unsigned FAR *bits, unsigned short FAR *work));