1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
|
/*
* Copyright (c) 2022, Michiel Visser <opensource@webmichiel.nl>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Types.h>
#include <LibCompress/BrotliDictionary.h>
// Include the 119.9 KiB of dictionary data from a binary file
extern u8 const brotli_dictionary_data[];
#if defined(AK_OS_MACOS)
asm(".const_data\n"
".globl _brotli_dictionary_data\n"
"_brotli_dictionary_data:\n");
#else
asm(".section .rodata\n"
".global brotli_dictionary_data\n"
"brotli_dictionary_data:\n");
#endif
asm(".incbin \"LibCompress/BrotliDictionaryData.bin\"\n"
".previous\n");
namespace Compress {
static size_t const bits_by_length[25] {
0, 0, 0, 0, 10, 10, 11, 11, 10, 10, 10, 10, 10, 9, 9, 8, 7, 7, 8, 7, 7, 6, 6, 5, 5
};
static size_t const offset_by_length[25] {
0, 0, 0, 0, 0, 4096, 9216, 21504, 35840, 44032, 53248, 63488, 74752, 87040, 93696, 100864,
104704, 106752, 108928, 113536, 115968, 118528, 119872, 121280, 122016
};
static int ferment(Bytes word, size_t pos)
{
if (word[pos] < 192) {
if (word[pos] >= 97 && word[pos] <= 122) {
word[pos] = word[pos] ^ 32;
}
return 1;
} else if (word[pos] < 224) {
if (pos + 1 < word.size()) {
word[pos + 1] = word[pos + 1] ^ 32;
}
return 2;
} else {
if (pos + 2 < word.size()) {
word[pos + 2] = word[pos + 2] ^ 5;
}
return 3;
}
}
static void ferment_first(Bytes word)
{
if (word.size() > 0) {
ferment(word, 0);
}
}
[[maybe_unused]] static void ferment_all(Bytes word)
{
size_t i = 0;
while (i < word.size()) {
i += ferment(word, i);
}
}
using BrotliDictionary::TransformationOperation::FermentAll;
using BrotliDictionary::TransformationOperation::FermentFirst;
using BrotliDictionary::TransformationOperation::Identity;
using BrotliDictionary::TransformationOperation::OmitFirst;
using BrotliDictionary::TransformationOperation::OmitLast;
constexpr static BrotliDictionary::Transformation transformations[121] {
// ID Prefix Transform Suffix
// -- ------ --------- ------
{ ""sv, Identity, 0, ""sv }, // 0 "" Identity ""
{ ""sv, Identity, 0, " "sv }, // 1 "" Identity " "
{ " "sv, Identity, 0, " "sv }, // 2 " " Identity " "
{ ""sv, OmitFirst, 1, ""sv }, // 3 "" OmitFirst1 ""
{ ""sv, FermentFirst, 0, " "sv }, // 4 "" FermentFirst " "
{ ""sv, Identity, 0, " the "sv }, // 5 "" Identity " the "
{ " "sv, Identity, 0, ""sv }, // 6 " " Identity ""
{ "s "sv, Identity, 0, " "sv }, // 7 "s " Identity " "
{ ""sv, Identity, 0, " of "sv }, // 8 "" Identity " of "
{ ""sv, FermentFirst, 0, ""sv }, // 9 "" FermentFirst ""
{ ""sv, Identity, 0, " and "sv }, // 10 "" Identity " and "
{ ""sv, OmitFirst, 2, ""sv }, // 11 "" OmitFirst2 ""
{ ""sv, OmitLast, 1, ""sv }, // 12 "" OmitLast1 ""
{ ", "sv, Identity, 0, " "sv }, // 13 ", " Identity " "
{ ""sv, Identity, 0, ", "sv }, // 14 "" Identity ", "
{ " "sv, FermentFirst, 0, " "sv }, // 15 " " FermentFirst " "
{ ""sv, Identity, 0, " in "sv }, // 16 "" Identity " in "
{ ""sv, Identity, 0, " to "sv }, // 17 "" Identity " to "
{ "e "sv, Identity, 0, " "sv }, // 18 "e " Identity " "
{ ""sv, Identity, 0, "\""sv }, // 19 "" Identity "\""
{ ""sv, Identity, 0, "."sv }, // 20 "" Identity "."
{ ""sv, Identity, 0, "\">"sv }, // 21 "" Identity "\">"
{ ""sv, Identity, 0, "\n"sv }, // 22 "" Identity "\n"
{ ""sv, OmitLast, 3, ""sv }, // 23 "" OmitLast3 ""
{ ""sv, Identity, 0, "]"sv }, // 24 "" Identity "]"
{ ""sv, Identity, 0, " for "sv }, // 25 "" Identity " for "
{ ""sv, OmitFirst, 3, ""sv }, // 26 "" OmitFirst3 ""
{ ""sv, OmitLast, 2, ""sv }, // 27 "" OmitLast2 ""
{ ""sv, Identity, 0, " a "sv }, // 28 "" Identity " a "
{ ""sv, Identity, 0, " that "sv }, // 29 "" Identity " that "
{ " "sv, FermentFirst, 0, ""sv }, // 30 " " FermentFirst ""
{ ""sv, Identity, 0, ". "sv }, // 31 "" Identity ". "
{ "."sv, Identity, 0, ""sv }, // 32 "." Identity ""
{ " "sv, Identity, 0, ", "sv }, // 33 " " Identity ", "
{ ""sv, OmitFirst, 4, ""sv }, // 34 "" OmitFirst4 ""
{ ""sv, Identity, 0, " with "sv }, // 35 "" Identity " with "
{ ""sv, Identity, 0, "'"sv }, // 36 "" Identity "'"
{ ""sv, Identity, 0, " from "sv }, // 37 "" Identity " from "
{ ""sv, Identity, 0, " by "sv }, // 38 "" Identity " by "
{ ""sv, OmitFirst, 5, ""sv }, // 39 "" OmitFirst5 ""
{ ""sv, OmitFirst, 6, ""sv }, // 40 "" OmitFirst6 ""
{ " the "sv, Identity, 0, ""sv }, // 41 " the " Identity ""
{ ""sv, OmitLast, 4, ""sv }, // 42 "" OmitLast4 ""
{ ""sv, Identity, 0, ". The "sv }, // 43 "" Identity ". The "
{ ""sv, FermentAll, 0, ""sv }, // 44 "" FermentAll ""
{ ""sv, Identity, 0, " on "sv }, // 45 "" Identity " on "
{ ""sv, Identity, 0, " as "sv }, // 46 "" Identity " as "
{ ""sv, Identity, 0, " is "sv }, // 47 "" Identity " is "
{ ""sv, OmitLast, 7, ""sv }, // 48 "" OmitLast7 ""
{ ""sv, OmitLast, 1, "ing "sv }, // 49 "" OmitLast1 "ing "
{ ""sv, Identity, 0, "\n\t"sv }, // 50 "" Identity "\n\t"
{ ""sv, Identity, 0, ":"sv }, // 51 "" Identity ":"
{ " "sv, Identity, 0, ". "sv }, // 52 " " Identity ". "
{ ""sv, Identity, 0, "ed "sv }, // 53 "" Identity "ed "
{ ""sv, OmitFirst, 9, ""sv }, // 54 "" OmitFirst9 ""
{ ""sv, OmitFirst, 7, ""sv }, // 55 "" OmitFirst7 ""
{ ""sv, OmitLast, 6, ""sv }, // 56 "" OmitLast6 ""
{ ""sv, Identity, 0, "("sv }, // 57 "" Identity "("
{ ""sv, FermentFirst, 0, ", "sv }, // 58 "" FermentFirst ", "
{ ""sv, OmitLast, 8, ""sv }, // 59 "" OmitLast8 ""
{ ""sv, Identity, 0, " at "sv }, // 60 "" Identity " at "
{ ""sv, Identity, 0, "ly "sv }, // 61 "" Identity "ly "
{ " the "sv, Identity, 0, " of "sv }, // 62 " the " Identity " of "
{ ""sv, OmitLast, 5, ""sv }, // 63 "" OmitLast5 ""
{ ""sv, OmitLast, 9, ""sv }, // 64 "" OmitLast9 ""
{ " "sv, FermentFirst, 0, ", "sv }, // 65 " " FermentFirst ", "
{ ""sv, FermentFirst, 0, "\""sv }, // 66 "" FermentFirst "\""
{ "."sv, Identity, 0, "("sv }, // 67 "." Identity "("
{ ""sv, FermentAll, 0, " "sv }, // 68 "" FermentAll " "
{ ""sv, FermentFirst, 0, "\">"sv }, // 69 "" FermentFirst "\">"
{ ""sv, Identity, 0, "=\""sv }, // 70 "" Identity "=\""
{ " "sv, Identity, 0, "."sv }, // 71 " " Identity "."
{ ".com/"sv, Identity, 0, ""sv }, // 72 ".com/" Identity ""
{ " the "sv, Identity, 0, " of the "sv }, // 73 " the " Identity " of the "
{ ""sv, FermentFirst, 0, "'"sv }, // 74 "" FermentFirst "'"
{ ""sv, Identity, 0, ". This "sv }, // 75 "" Identity ". This "
{ ""sv, Identity, 0, ","sv }, // 76 "" Identity ","
{ "."sv, Identity, 0, " "sv }, // 77 "." Identity " "
{ ""sv, FermentFirst, 0, "("sv }, // 78 "" FermentFirst "("
{ ""sv, FermentFirst, 0, "."sv }, // 79 "" FermentFirst "."
{ ""sv, Identity, 0, " not "sv }, // 80 "" Identity " not "
{ " "sv, Identity, 0, "=\""sv }, // 81 " " Identity "=\""
{ ""sv, Identity, 0, "er "sv }, // 82 "" Identity "er "
{ " "sv, FermentAll, 0, " "sv }, // 83 " " FermentAll " "
{ ""sv, Identity, 0, "al "sv }, // 84 "" Identity "al "
{ " "sv, FermentAll, 0, ""sv }, // 85 " " FermentAll ""
{ ""sv, Identity, 0, "='"sv }, // 86 "" Identity "='"
{ ""sv, FermentAll, 0, "\""sv }, // 87 "" FermentAll "\""
{ ""sv, FermentFirst, 0, ". "sv }, // 88 "" FermentFirst ". "
{ " "sv, Identity, 0, "("sv }, // 89 " " Identity "("
{ ""sv, Identity, 0, "ful "sv }, // 90 "" Identity "ful "
{ " "sv, FermentFirst, 0, ". "sv }, // 91 " " FermentFirst ". "
{ ""sv, Identity, 0, "ive "sv }, // 92 "" Identity "ive "
{ ""sv, Identity, 0, "less "sv }, // 93 "" Identity "less "
{ ""sv, FermentAll, 0, "'"sv }, // 94 "" FermentAll "'"
{ ""sv, Identity, 0, "est "sv }, // 95 "" Identity "est "
{ " "sv, FermentFirst, 0, "."sv }, // 96 " " FermentFirst "."
{ ""sv, FermentAll, 0, "\">"sv }, // 97 "" FermentAll "\">"
{ " "sv, Identity, 0, "='"sv }, // 98 " " Identity "='"
{ ""sv, FermentFirst, 0, ","sv }, // 99 "" FermentFirst ","
{ ""sv, Identity, 0, "ize "sv }, // 100 "" Identity "ize "
{ ""sv, FermentAll, 0, "."sv }, // 101 "" FermentAll "."
{ "\xc2\xa0"sv, Identity, 0, ""sv }, // 102 "\xc2\xa0" Identity ""
{ " "sv, Identity, 0, ","sv }, // 103 " " Identity ","
{ ""sv, FermentFirst, 0, "=\""sv }, // 104 "" FermentFirst "=\""
{ ""sv, FermentAll, 0, "=\""sv }, // 105 "" FermentAll "=\""
{ ""sv, Identity, 0, "ous "sv }, // 106 "" Identity "ous "
{ ""sv, FermentAll, 0, ", "sv }, // 107 "" FermentAll ", "
{ ""sv, FermentFirst, 0, "='"sv }, // 108 "" FermentFirst "='"
{ " "sv, FermentFirst, 0, ","sv }, // 109 " " FermentFirst ","
{ " "sv, FermentAll, 0, "=\""sv }, // 110 " " FermentAll "=\""
{ " "sv, FermentAll, 0, ", "sv }, // 111 " " FermentAll ", "
{ ""sv, FermentAll, 0, ","sv }, // 112 "" FermentAll ","
{ ""sv, FermentAll, 0, "("sv }, // 113 "" FermentAll "("
{ ""sv, FermentAll, 0, ". "sv }, // 114 "" FermentAll ". "
{ " "sv, FermentAll, 0, "."sv }, // 115 " " FermentAll "."
{ ""sv, FermentAll, 0, "='"sv }, // 116 "" FermentAll "='"
{ " "sv, FermentAll, 0, ". "sv }, // 117 " " FermentAll ". "
{ " "sv, FermentFirst, 0, "=\""sv }, // 118 " " FermentFirst "=\""
{ " "sv, FermentAll, 0, "='"sv }, // 119 " " FermentAll "='"
{ " "sv, FermentFirst, 0, "='"sv }, // 120 " " FermentFirst "='"
};
ErrorOr<ByteBuffer> BrotliDictionary::lookup_word(size_t index, size_t length)
{
if (length < 4 || length > 24)
return Error::from_string_literal("invalid dictionary lookup length");
size_t word_index = index % (1 << bits_by_length[length]);
ReadonlyBytes base_word { brotli_dictionary_data + offset_by_length[length] + (word_index * length), length };
size_t transform_id = index >> bits_by_length[length];
if (transform_id >= 121)
return Error::from_string_literal("invalid dictionary transformation");
auto transformation = transformations[transform_id];
ByteBuffer bb;
bb.append(transformation.prefix.bytes());
size_t prefix_length = bb.size();
switch (transformation.operation) {
case TransformationOperation::Identity:
bb.append(base_word);
break;
case TransformationOperation::FermentFirst:
bb.append(base_word);
ferment_first(bb.bytes().slice(prefix_length));
break;
case TransformationOperation::FermentAll:
bb.append(base_word);
ferment_all(bb.bytes().slice(prefix_length));
break;
case TransformationOperation::OmitFirst:
if (transformation.operation_data < base_word.size())
bb.append(base_word.slice(transformation.operation_data));
break;
case TransformationOperation::OmitLast:
if (transformation.operation_data < base_word.size())
bb.append(base_word.slice(0, base_word.size() - transformation.operation_data));
break;
}
bb.append(transformation.suffix.bytes());
return bb;
}
}
|
