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-rw-r--r--modules/brotli/common/transform.c62
1 files changed, 59 insertions, 3 deletions
diff --git a/modules/brotli/common/transform.c b/modules/brotli/common/transform.c
index 426e635fd..f8fa4335e 100644
--- a/modules/brotli/common/transform.c
+++ b/modules/brotli/common/transform.c
@@ -24,8 +24,8 @@ static const char kPrefixSuffix[217] =
/* 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";
-/* Cx _2 _7___ ___ _A _F _5 _8 */
+ "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,
@@ -160,12 +160,13 @@ static const uint8_t kTransformsData[] = {
0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 34,
};
-static BrotliTransforms kBrotliTransforms = {
+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}
};
@@ -190,6 +191,48 @@ static int ToUpperCase(uint8_t* p) {
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;
@@ -221,6 +264,19 @@ int BrotliTransformDictionaryWord(uint8_t* dst, const uint8_t* word, int len,
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;
+ }
}
}
{