1 | /* transforms is a part of ABI, but not API. |
2 | |
3 | It means that there are some functions that are supposed to be in "common" |
4 | library, but header itself is not placed into include/brotli. This way, |
5 | aforementioned functions will be available only to brotli internals. |
6 | */ |
7 | |
8 | #ifndef BROTLI_COMMON_TRANSFORM_H_ |
9 | #define BROTLI_COMMON_TRANSFORM_H_ |
10 | |
11 | #include <brotli/port.h> |
12 | #include <brotli/types.h> |
13 | |
14 | #if defined(__cplusplus) || defined(c_plusplus) |
15 | extern "C" { |
16 | #endif |
17 | |
18 | enum BrotliWordTransformType { |
19 | BROTLI_TRANSFORM_IDENTITY = 0, |
20 | BROTLI_TRANSFORM_OMIT_LAST_1 = 1, |
21 | BROTLI_TRANSFORM_OMIT_LAST_2 = 2, |
22 | BROTLI_TRANSFORM_OMIT_LAST_3 = 3, |
23 | BROTLI_TRANSFORM_OMIT_LAST_4 = 4, |
24 | BROTLI_TRANSFORM_OMIT_LAST_5 = 5, |
25 | BROTLI_TRANSFORM_OMIT_LAST_6 = 6, |
26 | BROTLI_TRANSFORM_OMIT_LAST_7 = 7, |
27 | BROTLI_TRANSFORM_OMIT_LAST_8 = 8, |
28 | BROTLI_TRANSFORM_OMIT_LAST_9 = 9, |
29 | BROTLI_TRANSFORM_UPPERCASE_FIRST = 10, |
30 | BROTLI_TRANSFORM_UPPERCASE_ALL = 11, |
31 | BROTLI_TRANSFORM_OMIT_FIRST_1 = 12, |
32 | BROTLI_TRANSFORM_OMIT_FIRST_2 = 13, |
33 | BROTLI_TRANSFORM_OMIT_FIRST_3 = 14, |
34 | BROTLI_TRANSFORM_OMIT_FIRST_4 = 15, |
35 | BROTLI_TRANSFORM_OMIT_FIRST_5 = 16, |
36 | BROTLI_TRANSFORM_OMIT_FIRST_6 = 17, |
37 | BROTLI_TRANSFORM_OMIT_FIRST_7 = 18, |
38 | BROTLI_TRANSFORM_OMIT_FIRST_8 = 19, |
39 | BROTLI_TRANSFORM_OMIT_FIRST_9 = 20, |
40 | BROTLI_TRANSFORM_SHIFT_FIRST = 21, |
41 | BROTLI_TRANSFORM_SHIFT_ALL = 22, |
42 | BROTLI_NUM_TRANSFORM_TYPES /* Counts transforms, not a transform itself. */ |
43 | }; |
44 | |
45 | #define BROTLI_TRANSFORMS_MAX_CUT_OFF BROTLI_TRANSFORM_OMIT_LAST_9 |
46 | |
47 | typedef struct BrotliTransforms { |
48 | uint16_t prefix_suffix_size; |
49 | /* Last character must be null, so prefix_suffix_size must be at least 1. */ |
50 | const uint8_t* prefix_suffix; |
51 | const uint16_t* prefix_suffix_map; |
52 | uint32_t num_transforms; |
53 | /* Each entry is a [prefix_id, transform, suffix_id] triplet. */ |
54 | const uint8_t* transforms; |
55 | /* Shift for BROTLI_TRANSFORM_SHIFT_FIRST and BROTLI_TRANSFORM_SHIFT_ALL, |
56 | must be NULL if and only if no such transforms are present. */ |
57 | const uint8_t* params; |
58 | /* Indices of transforms like ["", BROTLI_TRANSFORM_OMIT_LAST_#, ""]. |
59 | 0-th element corresponds to ["", BROTLI_TRANSFORM_IDENTITY, ""]. |
60 | -1, if cut-off transform does not exist. */ |
61 | int16_t cutOffTransforms[BROTLI_TRANSFORMS_MAX_CUT_OFF + 1]; |
62 | } BrotliTransforms; |
63 | |
64 | /* T is BrotliTransforms*; result is uint8_t. */ |
65 | #define BROTLI_TRANSFORM_PREFIX_ID(T, I) ((T)->transforms[((I) * 3) + 0]) |
66 | #define BROTLI_TRANSFORM_TYPE(T, I) ((T)->transforms[((I) * 3) + 1]) |
67 | #define BROTLI_TRANSFORM_SUFFIX_ID(T, I) ((T)->transforms[((I) * 3) + 2]) |
68 | |
69 | /* T is BrotliTransforms*; result is const uint8_t*. */ |
70 | #define BROTLI_TRANSFORM_PREFIX(T, I) (&(T)->prefix_suffix[ \ |
71 | (T)->prefix_suffix_map[BROTLI_TRANSFORM_PREFIX_ID(T, I)]]) |
72 | #define BROTLI_TRANSFORM_SUFFIX(T, I) (&(T)->prefix_suffix[ \ |
73 | (T)->prefix_suffix_map[BROTLI_TRANSFORM_SUFFIX_ID(T, I)]]) |
74 | |
75 | BROTLI_COMMON_API const BrotliTransforms* BrotliGetTransforms(void); |
76 | |
77 | BROTLI_COMMON_API int BrotliTransformDictionaryWord( |
78 | uint8_t* dst, const uint8_t* word, int len, |
79 | const BrotliTransforms* transforms, int transform_idx); |
80 | |
81 | #if defined(__cplusplus) || defined(c_plusplus) |
82 | } /* extern "C" */ |
83 | #endif |
84 | |
85 | #endif /* BROTLI_COMMON_TRANSFORM_H_ */ |
86 | |