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1#ifndef INFTREES_H2#define INFTREES_H3 4/* inftrees.h -- header to use inftrees.c5 * Copyright (C) 1995-2005 Mark Adler6 * For conditions of distribution and use, see copyright notice in zlib.h7 */8 9/* WARNING: this file should *not* be used by applications. It is10 part of the implementation of the compression library and is11 subject to change. Applications should only use zlib.h.12 */13 14/* Structure for decoding tables. Each entry provides either the15 information needed to do the operation requested by the code that16 indexed that table entry, or it provides a pointer to another17 table that indexes more bits of the code. op indicates whether18 the entry is a pointer to another table, a literal, a length or19 distance, an end-of-block, or an invalid code. For a table20 pointer, the low four bits of op is the number of index bits of21 that table. For a length or distance, the low four bits of op22 is the number of extra bits to get after the code. bits is23 the number of bits in this code or part of the code to drop off24 of the bit buffer. val is the actual byte to output in the case25 of a literal, the base length or distance, or the offset from26 the current table to the next table. Each entry is four bytes. */27typedef struct {28 unsigned char op; /* operation, extra bits, table bits */29 unsigned char bits; /* bits in this part of the code */30 unsigned short val; /* offset in table or code value */31} code;32 33/* op values as set by inflate_table():34 00000000 - literal35 0000tttt - table link, tttt != 0 is the number of table index bits36 0001eeee - length or distance, eeee is the number of extra bits37 01100000 - end of block38 01000000 - invalid code39 */40 41/* Maximum size of dynamic tree. The maximum found in a long but non-42 exhaustive search was 1444 code structures (852 for length/literals43 and 592 for distances, the latter actually the result of an44 exhaustive search). The true maximum is not known, but the value45 below is more than safe. */46#define ENOUGH 204847#define MAXD 59248 49/* Type of code to build for inftable() */50typedef enum {51 CODES,52 LENS,53 DISTS54} codetype;55 56extern int zlib_inflate_table (codetype type, unsigned short *lens,57 unsigned codes, code **table,58 unsigned *bits, unsigned short *work);59#endif60