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Diffstat (limited to 'java/org/brotli/dec/Decode.java')
-rwxr-xr-xjava/org/brotli/dec/Decode.java47
1 files changed, 35 insertions, 12 deletions
diff --git a/java/org/brotli/dec/Decode.java b/java/org/brotli/dec/Decode.java
index 4e1e35e..4a1ded6 100755
--- a/java/org/brotli/dec/Decode.java
+++ b/java/org/brotli/dec/Decode.java
@@ -124,6 +124,7 @@ final class Decode {
};
private static int decodeWindowBits(State s) {
+ BitReader.fillBitWindow(s);
if (BitReader.readFewBits(s, 1) == 0) {
return 16;
}
@@ -178,6 +179,7 @@ final class Decode {
* Decodes a number in the range [0..255], by reading 1 - 11 bits.
*/
private static int decodeVarLenUnsignedByte(State s) {
+ BitReader.fillBitWindow(s);
if (BitReader.readFewBits(s, 1) != 0) {
int n = BitReader.readFewBits(s, 3);
if (n == 0) {
@@ -190,6 +192,7 @@ final class Decode {
}
private static void decodeMetaBlockLength(State s) {
+ BitReader.fillBitWindow(s);
s.inputEnd = BitReader.readFewBits(s, 1);
s.metaBlockLength = 0;
s.isUncompressed = 0;
@@ -208,6 +211,7 @@ final class Decode {
return;
}
for (int i = 0; i < sizeBytes; i++) {
+ BitReader.fillBitWindow(s);
int bits = BitReader.readFewBits(s, 8);
if (bits == 0 && i + 1 == sizeBytes && sizeBytes > 1) {
throw new BrotliRuntimeException("Exuberant nibble");
@@ -216,6 +220,7 @@ final class Decode {
}
} else {
for (int i = 0; i < sizeNibbles; i++) {
+ BitReader.fillBitWindow(s);
int bits = BitReader.readFewBits(s, 4);
if (bits == 0 && i + 1 == sizeNibbles && sizeNibbles > 4) {
throw new BrotliRuntimeException("Exuberant nibble");
@@ -252,6 +257,7 @@ final class Decode {
BitReader.fillBitWindow(s);
int code = readSymbol(table, offset, s);
int n = BLOCK_LENGTH_N_BITS[code];
+ BitReader.fillBitWindow(s);
return BLOCK_LENGTH_OFFSET[code] + BitReader.readBits(s, n);
}
@@ -325,6 +331,7 @@ final class Decode {
repeat -= 2;
repeat <<= extraBits;
}
+ BitReader.fillBitWindow(s);
repeat += BitReader.readFewBits(s, extraBits) + 3;
int repeatDelta = repeat - oldRepeat;
if (symbol + repeatDelta > numSymbols) {
@@ -363,6 +370,7 @@ final class Decode {
BitReader.readMoreInput(s);
// TODO: Avoid allocation.
int[] codeLengths = new int[alphabetSize];
+ BitReader.fillBitWindow(s);
simpleCodeOrSkip = BitReader.readFewBits(s, 2);
if (simpleCodeOrSkip == 1) { // Read symbols, codes & code lengths directly.
int maxBitsCounter = alphabetSize - 1;
@@ -376,6 +384,7 @@ final class Decode {
// TODO: uncomment when codeLengths is reused.
// Utils.fillWithZeroes(codeLengths, 0, alphabetSize);
for (int i = 0; i < numSymbols; i++) {
+ BitReader.fillBitWindow(s);
symbols[i] = BitReader.readFewBits(s, maxBits) % alphabetSize;
codeLengths[symbols[i]] = 2;
}
@@ -433,6 +442,7 @@ final class Decode {
return numTrees;
}
+ BitReader.fillBitWindow(s);
int useRleForZeros = BitReader.readFewBits(s, 1);
int maxRunLengthPrefix = 0;
if (useRleForZeros != 0) {
@@ -448,6 +458,7 @@ final class Decode {
contextMap[i] = 0;
i++;
} else if (code <= maxRunLengthPrefix) {
+ BitReader.fillBitWindow(s);
int reps = (1 << code) + BitReader.readFewBits(s, code);
while (reps != 0) {
if (i >= contextMapSize) {
@@ -462,6 +473,7 @@ final class Decode {
i++;
}
}
+ BitReader.fillBitWindow(s);
if (BitReader.readFewBits(s, 1) == 1) {
inverseMoveToFrontTransform(contextMap, contextMapSize);
}
@@ -590,6 +602,7 @@ final class Decode {
s.distanceBlockLength = readMetablockPartition(s, 2, s.numDistanceBlockTypes);
BitReader.readMoreInput(s);
+ BitReader.fillBitWindow(s);
s.distancePostfixBits = BitReader.readFewBits(s, 2);
s.numDirectDistanceCodes =
NUM_DISTANCE_SHORT_CODES + (BitReader.readFewBits(s, 4) << s.distancePostfixBits);
@@ -601,6 +614,7 @@ final class Decode {
/* Ensure that less than 256 bits read between readMoreInput. */
int limit = Math.min(i + 96, s.numLiteralBlockTypes);
for (; i < limit; ++i) {
+ BitReader.fillBitWindow(s);
s.contextModes[i] = (byte) (BitReader.readFewBits(s, 2));
}
BitReader.readMoreInput(s);
@@ -671,10 +685,6 @@ final class Decode {
}
private static int writeRingBuffer(State s) {
- if (s.bytesToIgnore != 0) {
- s.bytesWritten += s.bytesToIgnore;
- s.bytesToIgnore = 0;
- }
int toWrite = Math.min(s.outputLength - s.outputUsed,
s.bytesToWrite - s.bytesWritten);
if (toWrite != 0) {
@@ -752,11 +762,15 @@ final class Decode {
s.distanceCode = -1;
}
int insertCode = INSERT_RANGE_LUT[rangeIdx] + ((cmdCode >>> 3) & 7);
+ BitReader.fillBitWindow(s);
+ int insertBits = INSERT_LENGTH_N_BITS[insertCode];
+ int insertExtra = BitReader.readBits(s, insertBits);
+ s.insertLength = INSERT_LENGTH_OFFSET[insertCode] + insertExtra;
int copyCode = COPY_RANGE_LUT[rangeIdx] + (cmdCode & 7);
- s.insertLength = INSERT_LENGTH_OFFSET[insertCode] + BitReader
- .readBits(s, INSERT_LENGTH_N_BITS[insertCode]);
- s.copyLength = COPY_LENGTH_OFFSET[copyCode] + BitReader
- .readBits(s, COPY_LENGTH_N_BITS[copyCode]);
+ BitReader.fillBitWindow(s);
+ int copyBits = COPY_LENGTH_N_BITS[copyCode];
+ int copyExtra = BitReader.readBits(s, copyBits);
+ s.copyLength = COPY_LENGTH_OFFSET[copyCode] + copyExtra;
s.j = 0;
s.runningState = INSERT_LOOP;
@@ -833,8 +847,10 @@ final class Decode {
s.distanceCode >>>= s.distancePostfixBits;
int n = (s.distanceCode >>> 1) + 1;
int offset = ((2 + (s.distanceCode & 1)) << n) - 4;
+ BitReader.fillBitWindow(s);
+ int distanceExtra = BitReader.readBits(s, n);
s.distanceCode = s.numDirectDistanceCodes + postfix
- + ((offset + BitReader.readBits(s, n)) << s.distancePostfixBits);
+ + ((offset + distanceExtra) << s.distancePostfixBits);
}
}
@@ -873,9 +889,15 @@ final class Decode {
int src = (s.pos - s.distance) & ringBufferMask;
int dst = s.pos;
int copyLength = s.copyLength - s.j;
- if ((src + copyLength < ringBufferMask) && (dst + copyLength < ringBufferMask)) {
- for (int k = 0; k < copyLength; ++k) {
- ringBuffer[dst++] = ringBuffer[src++];
+ int srcEnd = src + copyLength;
+ int dstEnd = dst + copyLength;
+ if ((srcEnd < ringBufferMask) && (dstEnd < ringBufferMask)) {
+ if (copyLength < 12 || (srcEnd > dst && dstEnd > src)) {
+ for (int k = 0; k < copyLength; ++k) {
+ ringBuffer[dst++] = ringBuffer[src++];
+ }
+ } else {
+ Utils.copyBytesWithin(ringBuffer, dst, src, srcEnd);
}
s.j += copyLength;
s.metaBlockLength -= copyLength;
@@ -941,6 +963,7 @@ final class Decode {
while (s.metaBlockLength > 0) {
BitReader.readMoreInput(s);
// Optimize
+ BitReader.fillBitWindow(s);
BitReader.readFewBits(s, 8);
s.metaBlockLength--;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-08 15:57:37 +0000