xref: /aosp_15_r20/external/cronet/third_party/brotli/common/context.c (revision 6777b5387eb2ff775bb5750e3f5d96f37fb7352b) 
1*6777b538SAndroid Build Coastguard Worker #include "context.h"
2*6777b538SAndroid Build Coastguard Worker 
3*6777b538SAndroid Build Coastguard Worker #include <brotli/types.h>
4*6777b538SAndroid Build Coastguard Worker 
5*6777b538SAndroid Build Coastguard Worker /* Common context lookup table for all context modes. */
6*6777b538SAndroid Build Coastguard Worker const uint8_t _kBrotliContextLookupTable[2048] = {
7*6777b538SAndroid Build Coastguard Worker   /* CONTEXT_LSB6, last byte. */
8*6777b538SAndroid Build Coastguard Worker    0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
9*6777b538SAndroid Build Coastguard Worker   16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
10*6777b538SAndroid Build Coastguard Worker   32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
11*6777b538SAndroid Build Coastguard Worker   48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
12*6777b538SAndroid Build Coastguard Worker    0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
13*6777b538SAndroid Build Coastguard Worker   16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
14*6777b538SAndroid Build Coastguard Worker   32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
15*6777b538SAndroid Build Coastguard Worker   48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
16*6777b538SAndroid Build Coastguard Worker    0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
17*6777b538SAndroid Build Coastguard Worker   16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
18*6777b538SAndroid Build Coastguard Worker   32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
19*6777b538SAndroid Build Coastguard Worker   48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
20*6777b538SAndroid Build Coastguard Worker    0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
21*6777b538SAndroid Build Coastguard Worker   16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
22*6777b538SAndroid Build Coastguard Worker   32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
23*6777b538SAndroid Build Coastguard Worker   48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
24*6777b538SAndroid Build Coastguard Worker 
25*6777b538SAndroid Build Coastguard Worker   /* CONTEXT_LSB6, second last byte, */
26*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
27*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
28*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
29*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
30*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
31*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
32*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
33*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
34*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
35*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
36*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
37*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
38*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
39*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
40*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
41*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
42*6777b538SAndroid Build Coastguard Worker 
43*6777b538SAndroid Build Coastguard Worker   /* CONTEXT_MSB6, last byte. */
44*6777b538SAndroid Build Coastguard Worker    0,  0,  0,  0,  1,  1,  1,  1,  2,  2,  2,  2,  3,  3,  3,  3,
45*6777b538SAndroid Build Coastguard Worker    4,  4,  4,  4,  5,  5,  5,  5,  6,  6,  6,  6,  7,  7,  7,  7,
46*6777b538SAndroid Build Coastguard Worker    8,  8,  8,  8,  9,  9,  9,  9, 10, 10, 10, 10, 11, 11, 11, 11,
47*6777b538SAndroid Build Coastguard Worker   12, 12, 12, 12, 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15,
48*6777b538SAndroid Build Coastguard Worker   16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18, 19, 19, 19, 19,
49*6777b538SAndroid Build Coastguard Worker   20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23,
50*6777b538SAndroid Build Coastguard Worker   24, 24, 24, 24, 25, 25, 25, 25, 26, 26, 26, 26, 27, 27, 27, 27,
51*6777b538SAndroid Build Coastguard Worker   28, 28, 28, 28, 29, 29, 29, 29, 30, 30, 30, 30, 31, 31, 31, 31,
52*6777b538SAndroid Build Coastguard Worker   32, 32, 32, 32, 33, 33, 33, 33, 34, 34, 34, 34, 35, 35, 35, 35,
53*6777b538SAndroid Build Coastguard Worker   36, 36, 36, 36, 37, 37, 37, 37, 38, 38, 38, 38, 39, 39, 39, 39,
54*6777b538SAndroid Build Coastguard Worker   40, 40, 40, 40, 41, 41, 41, 41, 42, 42, 42, 42, 43, 43, 43, 43,
55*6777b538SAndroid Build Coastguard Worker   44, 44, 44, 44, 45, 45, 45, 45, 46, 46, 46, 46, 47, 47, 47, 47,
56*6777b538SAndroid Build Coastguard Worker   48, 48, 48, 48, 49, 49, 49, 49, 50, 50, 50, 50, 51, 51, 51, 51,
57*6777b538SAndroid Build Coastguard Worker   52, 52, 52, 52, 53, 53, 53, 53, 54, 54, 54, 54, 55, 55, 55, 55,
58*6777b538SAndroid Build Coastguard Worker   56, 56, 56, 56, 57, 57, 57, 57, 58, 58, 58, 58, 59, 59, 59, 59,
59*6777b538SAndroid Build Coastguard Worker   60, 60, 60, 60, 61, 61, 61, 61, 62, 62, 62, 62, 63, 63, 63, 63,
60*6777b538SAndroid Build Coastguard Worker 
61*6777b538SAndroid Build Coastguard Worker   /* CONTEXT_MSB6, second last byte, */
62*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
63*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
64*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
65*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
66*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
67*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
68*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
69*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
70*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
71*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
72*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
73*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
74*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
75*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
76*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
77*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
78*6777b538SAndroid Build Coastguard Worker 
79*6777b538SAndroid Build Coastguard Worker   /* CONTEXT_UTF8, last byte. */
80*6777b538SAndroid Build Coastguard Worker   /* ASCII range. */
81*6777b538SAndroid Build Coastguard Worker    0,  0,  0,  0,  0,  0,  0,  0,  0,  4,  4,  0,  0,  4,  0,  0,
82*6777b538SAndroid Build Coastguard Worker    0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
83*6777b538SAndroid Build Coastguard Worker    8, 12, 16, 12, 12, 20, 12, 16, 24, 28, 12, 12, 32, 12, 36, 12,
84*6777b538SAndroid Build Coastguard Worker   44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 32, 32, 24, 40, 28, 12,
85*6777b538SAndroid Build Coastguard Worker   12, 48, 52, 52, 52, 48, 52, 52, 52, 48, 52, 52, 52, 52, 52, 48,
86*6777b538SAndroid Build Coastguard Worker   52, 52, 52, 52, 52, 48, 52, 52, 52, 52, 52, 24, 12, 28, 12, 12,
87*6777b538SAndroid Build Coastguard Worker   12, 56, 60, 60, 60, 56, 60, 60, 60, 56, 60, 60, 60, 60, 60, 56,
88*6777b538SAndroid Build Coastguard Worker   60, 60, 60, 60, 60, 56, 60, 60, 60, 60, 60, 24, 12, 28, 12,  0,
89*6777b538SAndroid Build Coastguard Worker   /* UTF8 continuation byte range. */
90*6777b538SAndroid Build Coastguard Worker   0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
91*6777b538SAndroid Build Coastguard Worker   0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
92*6777b538SAndroid Build Coastguard Worker   0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
93*6777b538SAndroid Build Coastguard Worker   0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
94*6777b538SAndroid Build Coastguard Worker   /* UTF8 lead byte range. */
95*6777b538SAndroid Build Coastguard Worker   2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,
96*6777b538SAndroid Build Coastguard Worker   2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,
97*6777b538SAndroid Build Coastguard Worker   2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,
98*6777b538SAndroid Build Coastguard Worker   2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 3,
99*6777b538SAndroid Build Coastguard Worker 
100*6777b538SAndroid Build Coastguard Worker   /* CONTEXT_UTF8 second last byte. */
101*6777b538SAndroid Build Coastguard Worker   /* ASCII range. */
102*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
103*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
104*6777b538SAndroid Build Coastguard Worker   0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
105*6777b538SAndroid Build Coastguard Worker   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1,
106*6777b538SAndroid Build Coastguard Worker   1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
107*6777b538SAndroid Build Coastguard Worker   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1,
108*6777b538SAndroid Build Coastguard Worker   1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
109*6777b538SAndroid Build Coastguard Worker   3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 1, 1, 1, 1, 0,
110*6777b538SAndroid Build Coastguard Worker   /* UTF8 continuation byte range. */
111*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
112*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
113*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
114*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
115*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
116*6777b538SAndroid Build Coastguard Worker   /* UTF8 lead byte range. */
117*6777b538SAndroid Build Coastguard Worker   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
118*6777b538SAndroid Build Coastguard Worker   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
119*6777b538SAndroid Build Coastguard Worker   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
120*6777b538SAndroid Build Coastguard Worker 
121*6777b538SAndroid Build Coastguard Worker   /* CONTEXT_SIGNED, last byte, same as the above values shifted by 3 bits. */
122*6777b538SAndroid Build Coastguard Worker    0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
123*6777b538SAndroid Build Coastguard Worker   16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
124*6777b538SAndroid Build Coastguard Worker   16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
125*6777b538SAndroid Build Coastguard Worker   16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
126*6777b538SAndroid Build Coastguard Worker   24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
127*6777b538SAndroid Build Coastguard Worker   24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
128*6777b538SAndroid Build Coastguard Worker   24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
129*6777b538SAndroid Build Coastguard Worker   24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
130*6777b538SAndroid Build Coastguard Worker   32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32,
131*6777b538SAndroid Build Coastguard Worker   32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32,
132*6777b538SAndroid Build Coastguard Worker   32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32,
133*6777b538SAndroid Build Coastguard Worker   32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32,
134*6777b538SAndroid Build Coastguard Worker   40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40,
135*6777b538SAndroid Build Coastguard Worker   40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40,
136*6777b538SAndroid Build Coastguard Worker   40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40,
137*6777b538SAndroid Build Coastguard Worker   48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 56,
138*6777b538SAndroid Build Coastguard Worker 
139*6777b538SAndroid Build Coastguard Worker   /* CONTEXT_SIGNED, second last byte. */
140*6777b538SAndroid Build Coastguard Worker   0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
141*6777b538SAndroid Build Coastguard Worker   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
142*6777b538SAndroid Build Coastguard Worker   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
143*6777b538SAndroid Build Coastguard Worker   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
144*6777b538SAndroid Build Coastguard Worker   3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
145*6777b538SAndroid Build Coastguard Worker   3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
146*6777b538SAndroid Build Coastguard Worker   3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
147*6777b538SAndroid Build Coastguard Worker   3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
148*6777b538SAndroid Build Coastguard Worker   4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
149*6777b538SAndroid Build Coastguard Worker   4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
150*6777b538SAndroid Build Coastguard Worker   4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
151*6777b538SAndroid Build Coastguard Worker   4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
152*6777b538SAndroid Build Coastguard Worker   5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
153*6777b538SAndroid Build Coastguard Worker   5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
154*6777b538SAndroid Build Coastguard Worker   5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
155*6777b538SAndroid Build Coastguard Worker   6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7,
156*6777b538SAndroid Build Coastguard Worker };
157