| 1 | /* |
| 2 | * Copyright (c) 2008 Apple Inc. All rights reserved. |
| 3 | * |
| 4 | * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ |
| 5 | * |
| 6 | * This file contains Original Code and/or Modifications of Original Code |
| 7 | * as defined in and that are subject to the Apple Public Source License |
| 8 | * Version 2.0 (the 'License'). You may not use this file except in |
| 9 | * compliance with the License. The rights granted to you under the License |
| 10 | * may not be used to create, or enable the creation or redistribution of, |
| 11 | * unlawful or unlicensed copies of an Apple operating system, or to |
| 12 | * circumvent, violate, or enable the circumvention or violation of, any |
| 13 | * terms of an Apple operating system software license agreement. |
| 14 | * |
| 15 | * Please obtain a copy of the License at |
| 16 | * http://www.opensource.apple.com/apsl/ and read it before using this file. |
| 17 | * |
| 18 | * The Original Code and all software distributed under the License are |
| 19 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
| 20 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
| 21 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, |
| 22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. |
| 23 | * Please see the License for the specific language governing rights and |
| 24 | * limitations under the License. |
| 25 | * |
| 26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ |
| 27 | */ |
| 28 | /* inftrees.h -- header to use inftrees.c |
| 29 | * Copyright (C) 1995-2005 Mark Adler |
| 30 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 31 | */ |
| 32 | |
| 33 | /* WARNING: this file should *not* be used by applications. It is |
| 34 | part of the implementation of the compression library and is |
| 35 | subject to change. Applications should only use zlib.h. |
| 36 | */ |
| 37 | |
| 38 | /* Structure for decoding tables. Each entry provides either the |
| 39 | information needed to do the operation requested by the code that |
| 40 | indexed that table entry, or it provides a pointer to another |
| 41 | table that indexes more bits of the code. op indicates whether |
| 42 | the entry is a pointer to another table, a literal, a length or |
| 43 | distance, an end-of-block, or an invalid code. For a table |
| 44 | pointer, the low four bits of op is the number of index bits of |
| 45 | that table. For a length or distance, the low four bits of op |
| 46 | is the number of extra bits to get after the code. bits is |
| 47 | the number of bits in this code or part of the code to drop off |
| 48 | of the bit buffer. val is the actual byte to output in the case |
| 49 | of a literal, the base length or distance, or the offset from |
| 50 | the current table to the next table. Each entry is four bytes. */ |
| 51 | typedef struct { |
| 52 | unsigned char op; /* operation, extra bits, table bits */ |
| 53 | unsigned char bits; /* bits in this part of the code */ |
| 54 | unsigned short val; /* offset in table or code value */ |
| 55 | } code; |
| 56 | |
| 57 | /* op values as set by inflate_table(): |
| 58 | 00000000 - literal |
| 59 | 0000tttt - table link, tttt != 0 is the number of table index bits |
| 60 | 0001eeee - length or distance, eeee is the number of extra bits |
| 61 | 01100000 - end of block |
| 62 | 01000000 - invalid code |
| 63 | */ |
| 64 | |
| 65 | /* Maximum size of dynamic tree. The maximum found in a long but non- |
| 66 | exhaustive search was 1444 code structures (852 for length/literals |
| 67 | and 592 for distances, the latter actually the result of an |
| 68 | exhaustive search). The true maximum is not known, but the value |
| 69 | below is more than safe. */ |
| 70 | #define ENOUGH 2048 |
| 71 | #define MAXD 592 |
| 72 | |
| 73 | /* Type of code to build for inftable() */ |
| 74 | typedef enum { |
| 75 | CODES, |
| 76 | LENS, |
| 77 | DISTS |
| 78 | } codetype; |
| 79 | |
| 80 | extern int inflate_table OF((codetype type, unsigned short FAR *lens, |
| 81 | unsigned codes, code FAR * FAR *table, |
| 82 | unsigned FAR *bits, unsigned short FAR *work)); |