1// This file is part of ICU4X. For terms of use, please see the file
2// called LICENSE at the top level of the ICU4X source tree
3// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).
4
5pub const FAST_TYPE_SHIFT: i32 = 6;
6
7/// Number of entries in a data block for code points below the fast limit. 64=0x40
8pub const FAST_TYPE_DATA_BLOCK_LENGTH: u32 = 1 << FAST_TYPE_SHIFT;
9
10/// Mask for getting the lower bits for the in-fast-data-block offset.
11pub const FAST_TYPE_DATA_MASK: u32 = FAST_TYPE_DATA_BLOCK_LENGTH - 1;
12
13/// Fast indexing limit for "fast"-type trie
14pub const FAST_TYPE_FAST_INDEXING_MAX: u32 = 0xffff;
15
16/// Fast indexing limit for "small"-type trie
17pub const SMALL_TYPE_FAST_INDEXING_MAX: u32 = 0xfff;
18
19/// Offset from dataLength (to be subtracted) for fetching the
20/// value returned for out-of-range code points and ill-formed UTF-8/16.
21pub const ERROR_VALUE_NEG_DATA_OFFSET: u32 = 1;
22
23/// Offset from dataLength (to be subtracted) for fetching the
24/// value returned for code points highStart..U+10FFFF.
25pub const HIGH_VALUE_NEG_DATA_OFFSET: u32 = 2;
26
27/// The length of the BMP index table. 1024=0x400
28pub const BMP_INDEX_LENGTH: u32 = 0x10000 >> FAST_TYPE_SHIFT;
29
30pub const SMALL_LIMIT: u32 = 0x1000;
31
32pub const SMALL_INDEX_LENGTH: u32 = SMALL_LIMIT >> FAST_TYPE_SHIFT;
33
34/// Shift size for getting the index-3 table offset.
35pub const SHIFT_3: u32 = 4;
36
37/// Shift size for getting the index-2 table offset.
38pub const SHIFT_2: u32 = 5 + SHIFT_3;
39
40/// Shift size for getting the index-1 table offset.
41pub const SHIFT_1: u32 = 5 + SHIFT_2;
42
43/// Difference between two shift sizes,
44/// for getting an index-2 offset from an index-3 offset. 5=9-4
45pub const SHIFT_2_3: u32 = SHIFT_2 - SHIFT_3;
46
47/// Difference between two shift sizes,
48/// for getting an index-1 offset from an index-2 offset. 5=14-9
49pub const SHIFT_1_2: u32 = SHIFT_1 - SHIFT_2;
50
51/// Number of index-1 entries for the BMP. (4)
52/// This part of the index-1 table is omitted from the serialized form.
53pub const OMITTED_BMP_INDEX_1_LENGTH: u32 = 0x10000 >> SHIFT_1;
54
55/// Number of entries in an index-2 block. 32=0x20
56pub const INDEX_2_BLOCK_LENGTH: u32 = 1 << SHIFT_1_2;
57
58/// Mask for getting the lower bits for the in-index-2-block offset.
59pub const INDEX_2_MASK: u32 = INDEX_2_BLOCK_LENGTH - 1;
60
61/// Number of code points per index-2 table entry. 512=0x200
62pub const CP_PER_INDEX_2_ENTRY: u32 = 1 << SHIFT_2;
63
64/// Number of entries in an index-3 block. 32=0x20
65pub const INDEX_3_BLOCK_LENGTH: u32 = 1 << SHIFT_2_3;
66
67/// Mask for getting the lower bits for the in-index-3-block offset.
68pub const INDEX_3_MASK: u32 = INDEX_3_BLOCK_LENGTH - 1;
69
70/// Number of entries in a small data block. 16=0x10
71pub const SMALL_DATA_BLOCK_LENGTH: u32 = 1 << SHIFT_3;
72
73/// Mask for getting the lower bits for the in-small-data-block offset.
74pub const SMALL_DATA_MASK: u32 = SMALL_DATA_BLOCK_LENGTH - 1;
75
76pub const CODE_POINT_MAX: u32 = 0x10ffff;
77