1 | /* |
2 | * Copyright (c) 2000-2013 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 | |
29 | /* direct-mapped partial matching compressor with simple 22/10 split |
30 | * |
31 | * Compresses buffers using a dictionary based match and partial match |
32 | * (high bits only or full match) scheme. |
33 | * |
34 | * Paul Wilson -- wilson@cs.utexas.edu |
35 | * Scott F. Kaplan -- sfkaplan@cs.utexas.edu |
36 | * September 1997 |
37 | */ |
38 | |
39 | /* compressed output format, in memory order |
40 | * 1. a four-word HEADER containing four one-word values: |
41 | * i. a one-word code saying what algorithm compressed the data |
42 | * ii. an integer WORD offset into the page saying |
43 | * where the queue position area starts |
44 | * iii. an integer WORD offset into the page saying where |
45 | * the low-bits area starts |
46 | * iv. an integer WORD offset into the page saying where the |
47 | * low-bits area ends |
48 | * |
49 | * 2. a 64-word TAGS AREA holding one two-bit tag for each word in |
50 | * the original (1024-word) page, packed 16 per word |
51 | * |
52 | * 3. a variable-sized FULL WORDS AREA (always word aligned and an |
53 | * integral number of words) holding full-word patterns that |
54 | * were not in the dictionary when encoded (i.e., dictionary misses) |
55 | * |
56 | * 4. a variable-sized QUEUE POSITIONS AREA (always word aligned and |
57 | * an integral number of words) holding four-bit queue positions, |
58 | * packed eight per word. |
59 | * |
60 | * 5. a variable-sized LOW BITS AREA (always word aligned and an |
61 | * integral number of words) holding ten-bit low-bit patterns |
62 | * (from partial matches), packed three per word. |
63 | */ |
64 | |
65 | #ifdef __cplusplus |
66 | extern "C" { |
67 | #endif |
68 | |
69 | #include <mach/vm_param.h> |
70 | |
71 | |
72 | #define WKdm_SCRATCH_BUF_SIZE_INTERNAL PAGE_SIZE |
73 | |
74 | typedef unsigned int WK_word; |
75 | |
76 | #if defined(__arm64__) |
77 | |
78 | void |
79 | WKdm_decompress_4k(const WK_word* src_buf, |
80 | WK_word* dest_buf, |
81 | WK_word* scratch, |
82 | unsigned int bytes); |
83 | int |
84 | WKdm_compress_4k(const WK_word* src_buf, |
85 | WK_word* dest_buf, |
86 | WK_word* scratch, |
87 | unsigned int limit); |
88 | |
89 | void |
90 | WKdm_decompress_16k(WK_word* src_buf, |
91 | WK_word* dest_buf, |
92 | WK_word* scratch, |
93 | unsigned int bytes); |
94 | int |
95 | WKdm_compress_16k(WK_word* src_buf, |
96 | WK_word* dest_buf, |
97 | WK_word* scratch, |
98 | unsigned int limit); |
99 | #else |
100 | |
101 | void |
102 | WKdm_decompress_new(WK_word* src_buf, |
103 | WK_word* dest_buf, |
104 | WK_word* scratch, |
105 | unsigned int bytes); |
106 | int |
107 | WKdm_compress_new(const WK_word* src_buf, |
108 | WK_word* dest_buf, |
109 | WK_word* scratch, |
110 | unsigned int limit); |
111 | #endif |
112 | |
113 | #ifdef __cplusplus |
114 | } /* extern "C" */ |
115 | #endif |
116 | |