1#[allow(dead_code)] const X: u16 = 0xffff;
10
11const FORWARD_TABLE: &[u16] = &[
12 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146,
13 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 260, 728, 321, 164, 317,
14 346, 167, 168, 352, 350, 356, 377, 173, 381, 379, 176, 261, 731, 322, 180, 318, 347, 711, 184,
15 353, 351, 357, 378, 733, 382, 380, 340, 193, 194, 258, 196, 313, 262, 199, 268, 201, 280, 203,
16 282, 205, 206, 270, 272, 323, 327, 211, 212, 336, 214, 215, 344, 366, 218, 368, 220, 221, 354,
17 223, 341, 225, 226, 259, 228, 314, 263, 231, 269, 233, 281, 235, 283, 237, 238, 271, 273, 324,
18 328, 243, 244, 337, 246, 247, 345, 367, 250, 369, 252, 253, 355, 729,
19]; #[inline]
23pub fn forward(code: u8) -> u16 {
24 FORWARD_TABLE[(code - 0x80) as usize]
25}
26
27#[cfg(not(feature = "no-optimized-legacy-encoding"))]
28const BACKWARD_TABLE_LOWER: &[u8] = &[
29 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 219, 251, 0, 0, 0, 0, 0, 0, 0, 172, 188, 175,
30 191, 174, 190, 0, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158,
31 159, 176, 0, 0, 0, 180, 0, 0, 0, 184, 0, 0, 0, 0, 0, 0, 0, 0, 162, 255, 0, 178, 0, 189, 0, 0,
32 193, 194, 0, 196, 0, 0, 199, 0, 201, 0, 203, 0, 205, 206, 0, 225, 226, 0, 228, 0, 0, 231, 0,
33 233, 0, 235, 0, 237, 238, 0, 163, 179, 209, 241, 0, 0, 210, 242, 0, 0, 0, 0, 0, 0, 0, 183, 0,
34 0, 0, 0, 0, 0, 0, 0, 0, 197, 229, 0, 0, 165, 181, 0, 128, 129, 130, 131, 132, 133, 134, 135,
35 136, 137, 138, 139, 140, 141, 142, 143, 160, 0, 0, 0, 164, 0, 0, 167, 168, 0, 0, 0, 0, 173, 0,
36 0, 0, 243, 244, 0, 246, 247, 0, 0, 250, 0, 252, 253, 0, 0, 195, 227, 161, 177, 198, 230, 0, 0,
37 0, 0, 200, 232, 207, 239, 208, 240, 0, 0, 0, 0, 0, 0, 202, 234, 204, 236, 0, 0, 0, 0, 211, 212,
38 0, 214, 215, 0, 0, 218, 0, 220, 221, 0, 223, 213, 245, 0, 0, 192, 224, 0, 0, 216, 248, 166,
39 182, 0, 0, 170, 186, 169, 185, 222, 254, 171, 187, 0, 0, 0, 0, 0, 0, 0, 0, 217, 249,
40]; #[cfg(not(feature = "no-optimized-legacy-encoding"))]
43const BACKWARD_TABLE_UPPER: &[u16] = &[
44 0, 0, 0, 0, 0, 0, 0, 0, 135, 32, 151, 48, 72, 208, 87, 165, 179, 195, 0, 119, 102, 224, 240,
45 16, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 111, 57,
46]; #[inline]
50#[cfg(not(feature = "no-optimized-legacy-encoding"))]
51pub fn backward(code: u32) -> u8 {
52 let offset = (code >> 4) as usize;
53 let offset = if offset < 46 {BACKWARD_TABLE_UPPER[offset] as usize} else {0};
54 BACKWARD_TABLE_LOWER[offset + ((code & 15) as usize)]
55}
56
57#[cfg(feature = "no-optimized-legacy-encoding")]
59pub fn backward(code: u32) -> u8 {
60 if code > 733 || ((0x400ff0u32 >> (code >> 5)) & 1) == 0 { return 0; }
61 let code = code as u16;
62 for i in 0..0x80 {
63 if FORWARD_TABLE[i as usize] == code { return 0x80 + i; }
64 }
65 0
66}
67
68#[cfg(test)]
69encoding_index_tests::single_byte_tests! {
70}