292 lines
10 KiB
C
292 lines
10 KiB
C
/* Copyright 2013 Google Inc. All Rights Reserved.
|
|
|
|
Distributed under MIT license.
|
|
See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
|
|
*/
|
|
|
|
#include "transform.h"
|
|
|
|
#if defined(__cplusplus) || defined(c_plusplus)
|
|
extern "C" {
|
|
#endif
|
|
|
|
/* RFC 7932 transforms string data */
|
|
static const char kPrefixSuffix[217] =
|
|
"\1 \2, \10 of the \4 of \2s \1.\5 and \4 "
|
|
/* 0x _0 _2 __5 _E _3 _6 _8 _E */
|
|
"in \1\"\4 to \2\">\1\n\2. \1]\5 for \3 a \6 "
|
|
/* 2x _3_ _5 _A_ _D_ _F _2 _4 _A _E */
|
|
"that \1\'\6 with \6 from \4 by \1(\6. T"
|
|
/* 4x _5_ _7 _E _5 _A _C */
|
|
"he \4 on \4 as \4 is \4ing \2\n\t\1:\3ed "
|
|
/* 6x _3 _8 _D _2 _7_ _ _A _C */
|
|
"\2=\"\4 at \3ly \1,\2=\'\5.com/\7. This \5"
|
|
/* 8x _0 _ _3 _8 _C _E _ _1 _7 _F */
|
|
" not \3er \3al \4ful \4ive \5less \4es"
|
|
/* Ax _5 _9 _D _2 _7 _D */
|
|
"t \4ize \2\xc2\xa0\4ous \5 the \2e "; /* \0 - implicit trailing zero. */
|
|
/* Cx _2 _7___ ___ _A _F _5 _8 */
|
|
|
|
static const uint16_t kPrefixSuffixMap[50] = {
|
|
0x00, 0x02, 0x05, 0x0E, 0x13, 0x16, 0x18, 0x1E, 0x23, 0x25,
|
|
0x2A, 0x2D, 0x2F, 0x32, 0x34, 0x3A, 0x3E, 0x45, 0x47, 0x4E,
|
|
0x55, 0x5A, 0x5C, 0x63, 0x68, 0x6D, 0x72, 0x77, 0x7A, 0x7C,
|
|
0x80, 0x83, 0x88, 0x8C, 0x8E, 0x91, 0x97, 0x9F, 0xA5, 0xA9,
|
|
0xAD, 0xB2, 0xB7, 0xBD, 0xC2, 0xC7, 0xCA, 0xCF, 0xD5, 0xD8
|
|
};
|
|
|
|
/* RFC 7932 transforms */
|
|
static const uint8_t kTransformsData[] = {
|
|
49, BROTLI_TRANSFORM_IDENTITY, 49,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 0,
|
|
0, BROTLI_TRANSFORM_IDENTITY, 0,
|
|
49, BROTLI_TRANSFORM_OMIT_FIRST_1, 49,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 0,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 47,
|
|
0, BROTLI_TRANSFORM_IDENTITY, 49,
|
|
4, BROTLI_TRANSFORM_IDENTITY, 0,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 3,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 49,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 6,
|
|
49, BROTLI_TRANSFORM_OMIT_FIRST_2, 49,
|
|
49, BROTLI_TRANSFORM_OMIT_LAST_1, 49,
|
|
1, BROTLI_TRANSFORM_IDENTITY, 0,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 1,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 0,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 7,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 9,
|
|
48, BROTLI_TRANSFORM_IDENTITY, 0,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 8,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 5,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 10,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 11,
|
|
49, BROTLI_TRANSFORM_OMIT_LAST_3, 49,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 13,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 14,
|
|
49, BROTLI_TRANSFORM_OMIT_FIRST_3, 49,
|
|
49, BROTLI_TRANSFORM_OMIT_LAST_2, 49,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 15,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 16,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 49,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 12,
|
|
5, BROTLI_TRANSFORM_IDENTITY, 49,
|
|
0, BROTLI_TRANSFORM_IDENTITY, 1,
|
|
49, BROTLI_TRANSFORM_OMIT_FIRST_4, 49,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 18,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 17,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 19,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 20,
|
|
49, BROTLI_TRANSFORM_OMIT_FIRST_5, 49,
|
|
49, BROTLI_TRANSFORM_OMIT_FIRST_6, 49,
|
|
47, BROTLI_TRANSFORM_IDENTITY, 49,
|
|
49, BROTLI_TRANSFORM_OMIT_LAST_4, 49,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 22,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 49,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 23,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 24,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 25,
|
|
49, BROTLI_TRANSFORM_OMIT_LAST_7, 49,
|
|
49, BROTLI_TRANSFORM_OMIT_LAST_1, 26,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 27,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 28,
|
|
0, BROTLI_TRANSFORM_IDENTITY, 12,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 29,
|
|
49, BROTLI_TRANSFORM_OMIT_FIRST_9, 49,
|
|
49, BROTLI_TRANSFORM_OMIT_FIRST_7, 49,
|
|
49, BROTLI_TRANSFORM_OMIT_LAST_6, 49,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 21,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 1,
|
|
49, BROTLI_TRANSFORM_OMIT_LAST_8, 49,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 31,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 32,
|
|
47, BROTLI_TRANSFORM_IDENTITY, 3,
|
|
49, BROTLI_TRANSFORM_OMIT_LAST_5, 49,
|
|
49, BROTLI_TRANSFORM_OMIT_LAST_9, 49,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 1,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 8,
|
|
5, BROTLI_TRANSFORM_IDENTITY, 21,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 0,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 10,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 30,
|
|
0, BROTLI_TRANSFORM_IDENTITY, 5,
|
|
35, BROTLI_TRANSFORM_IDENTITY, 49,
|
|
47, BROTLI_TRANSFORM_IDENTITY, 2,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 17,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 36,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 33,
|
|
5, BROTLI_TRANSFORM_IDENTITY, 0,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 21,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 5,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 37,
|
|
0, BROTLI_TRANSFORM_IDENTITY, 30,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 38,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_ALL, 0,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 39,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_ALL, 49,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 34,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 8,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 12,
|
|
0, BROTLI_TRANSFORM_IDENTITY, 21,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 40,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 12,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 41,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 42,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 17,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 43,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 5,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 10,
|
|
0, BROTLI_TRANSFORM_IDENTITY, 34,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 33,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 44,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 5,
|
|
45, BROTLI_TRANSFORM_IDENTITY, 49,
|
|
0, BROTLI_TRANSFORM_IDENTITY, 33,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 30,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 30,
|
|
49, BROTLI_TRANSFORM_IDENTITY, 46,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 1,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 34,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 33,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_ALL, 30,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_ALL, 1,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 33,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 21,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 12,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_ALL, 5,
|
|
49, BROTLI_TRANSFORM_UPPERCASE_ALL, 34,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_ALL, 12,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 30,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_ALL, 34,
|
|
0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 34,
|
|
};
|
|
|
|
static const BrotliTransforms kBrotliTransforms = {
|
|
sizeof(kPrefixSuffix),
|
|
(const uint8_t*)kPrefixSuffix,
|
|
kPrefixSuffixMap,
|
|
sizeof(kTransformsData) / (3 * sizeof(kTransformsData[0])),
|
|
kTransformsData,
|
|
NULL, /* no extra parameters */
|
|
{0, 12, 27, 23, 42, 63, 56, 48, 59, 64}
|
|
};
|
|
|
|
const BrotliTransforms* BrotliGetTransforms(void) {
|
|
return &kBrotliTransforms;
|
|
}
|
|
|
|
static int ToUpperCase(uint8_t* p) {
|
|
if (p[0] < 0xC0) {
|
|
if (p[0] >= 'a' && p[0] <= 'z') {
|
|
p[0] ^= 32;
|
|
}
|
|
return 1;
|
|
}
|
|
/* An overly simplified uppercasing model for UTF-8. */
|
|
if (p[0] < 0xE0) {
|
|
p[1] ^= 32;
|
|
return 2;
|
|
}
|
|
/* An arbitrary transform for three byte characters. */
|
|
p[2] ^= 5;
|
|
return 3;
|
|
}
|
|
|
|
static int Shift(uint8_t* word, int word_len, uint16_t parameter) {
|
|
/* Limited sign extension: scalar < (1 << 24). */
|
|
uint32_t scalar =
|
|
(parameter & 0x7FFFu) + (0x1000000u - (parameter & 0x8000u));
|
|
if (word[0] < 0x80) {
|
|
/* 1-byte rune / 0sssssss / 7 bit scalar (ASCII). */
|
|
scalar += (uint32_t)word[0];
|
|
word[0] = (uint8_t)(scalar & 0x7Fu);
|
|
return 1;
|
|
} else if (word[0] < 0xC0) {
|
|
/* Continuation / 10AAAAAA. */
|
|
return 1;
|
|
} else if (word[0] < 0xE0) {
|
|
/* 2-byte rune / 110sssss AAssssss / 11 bit scalar. */
|
|
if (word_len < 2) return 1;
|
|
scalar += (uint32_t)((word[1] & 0x3Fu) | ((word[0] & 0x1Fu) << 6u));
|
|
word[0] = (uint8_t)(0xC0 | ((scalar >> 6u) & 0x1F));
|
|
word[1] = (uint8_t)((word[1] & 0xC0) | (scalar & 0x3F));
|
|
return 2;
|
|
} else if (word[0] < 0xF0) {
|
|
/* 3-byte rune / 1110ssss AAssssss BBssssss / 16 bit scalar. */
|
|
if (word_len < 3) return word_len;
|
|
scalar += (uint32_t)((word[2] & 0x3Fu) | ((word[1] & 0x3Fu) << 6u) |
|
|
((word[0] & 0x0Fu) << 12u));
|
|
word[0] = (uint8_t)(0xE0 | ((scalar >> 12u) & 0x0F));
|
|
word[1] = (uint8_t)((word[1] & 0xC0) | ((scalar >> 6u) & 0x3F));
|
|
word[2] = (uint8_t)((word[2] & 0xC0) | (scalar & 0x3F));
|
|
return 3;
|
|
} else if (word[0] < 0xF8) {
|
|
/* 4-byte rune / 11110sss AAssssss BBssssss CCssssss / 21 bit scalar. */
|
|
if (word_len < 4) return word_len;
|
|
scalar += (uint32_t)((word[3] & 0x3Fu) | ((word[2] & 0x3Fu) << 6u) |
|
|
((word[1] & 0x3Fu) << 12u) | ((word[0] & 0x07u) << 18u));
|
|
word[0] = (uint8_t)(0xF0 | ((scalar >> 18u) & 0x07));
|
|
word[1] = (uint8_t)((word[1] & 0xC0) | ((scalar >> 12u) & 0x3F));
|
|
word[2] = (uint8_t)((word[2] & 0xC0) | ((scalar >> 6u) & 0x3F));
|
|
word[3] = (uint8_t)((word[3] & 0xC0) | (scalar & 0x3F));
|
|
return 4;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
int BrotliTransformDictionaryWord(uint8_t* dst, const uint8_t* word, int len,
|
|
const BrotliTransforms* transforms, int transform_idx) {
|
|
int idx = 0;
|
|
const uint8_t* prefix = BROTLI_TRANSFORM_PREFIX(transforms, transform_idx);
|
|
uint8_t type = BROTLI_TRANSFORM_TYPE(transforms, transform_idx);
|
|
const uint8_t* suffix = BROTLI_TRANSFORM_SUFFIX(transforms, transform_idx);
|
|
{
|
|
int prefix_len = *prefix++;
|
|
while (prefix_len--) { dst[idx++] = *prefix++; }
|
|
}
|
|
{
|
|
const int t = type;
|
|
int i = 0;
|
|
if (t <= BROTLI_TRANSFORM_OMIT_LAST_9) {
|
|
len -= t;
|
|
} else if (t >= BROTLI_TRANSFORM_OMIT_FIRST_1
|
|
&& t <= BROTLI_TRANSFORM_OMIT_FIRST_9) {
|
|
int skip = t - (BROTLI_TRANSFORM_OMIT_FIRST_1 - 1);
|
|
word += skip;
|
|
len -= skip;
|
|
}
|
|
while (i < len) { dst[idx++] = word[i++]; }
|
|
if (t == BROTLI_TRANSFORM_UPPERCASE_FIRST) {
|
|
ToUpperCase(&dst[idx - len]);
|
|
} else if (t == BROTLI_TRANSFORM_UPPERCASE_ALL) {
|
|
uint8_t* uppercase = &dst[idx - len];
|
|
while (len > 0) {
|
|
int step = ToUpperCase(uppercase);
|
|
uppercase += step;
|
|
len -= step;
|
|
}
|
|
} else if (t == BROTLI_TRANSFORM_SHIFT_FIRST) {
|
|
uint16_t param = (uint16_t)(transforms->params[transform_idx * 2]
|
|
+ (transforms->params[transform_idx * 2 + 1] << 8u));
|
|
Shift(&dst[idx - len], len, param);
|
|
} else if (t == BROTLI_TRANSFORM_SHIFT_ALL) {
|
|
uint16_t param = (uint16_t)(transforms->params[transform_idx * 2]
|
|
+ (transforms->params[transform_idx * 2 + 1] << 8u));
|
|
uint8_t* shift = &dst[idx - len];
|
|
while (len > 0) {
|
|
int step = Shift(shift, len, param);
|
|
shift += step;
|
|
len -= step;
|
|
}
|
|
}
|
|
}
|
|
{
|
|
int suffix_len = *suffix++;
|
|
while (suffix_len--) { dst[idx++] = *suffix++; }
|
|
return idx;
|
|
}
|
|
}
|
|
|
|
#if defined(__cplusplus) || defined(c_plusplus)
|
|
} /* extern "C" */
|
|
#endif
|