net.jpountz.lz4.LZ4Utils Maven / Gradle / Ivy
package net.jpountz.lz4;
/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import static net.jpountz.lz4.LZ4Constants.HASH_LOG;
import static net.jpountz.lz4.LZ4Constants.HASH_LOG_64K;
import static net.jpountz.lz4.LZ4Constants.HASH_LOG_HC;
import static net.jpountz.lz4.LZ4Constants.LAST_LITERALS;
import static net.jpountz.lz4.LZ4Constants.MIN_MATCH;
import static net.jpountz.lz4.LZ4Constants.ML_BITS;
import static net.jpountz.lz4.LZ4Constants.ML_MASK;
import static net.jpountz.lz4.LZ4Constants.RUN_MASK;
import net.jpountz.util.SafeUtils;
enum LZ4Utils {
;
private static final int MAX_INPUT_SIZE = 0x7E000000;
static int maxCompressedLength(int length) {
if (length < 0) {
throw new IllegalArgumentException("length must be >= 0, got " + length);
} else if (length >= MAX_INPUT_SIZE) {
throw new IllegalArgumentException("length must be < " + MAX_INPUT_SIZE);
}
return length + length / 255 + 16;
}
static int hash(int i) {
return (i * -1640531535) >>> ((MIN_MATCH * 8) - HASH_LOG);
}
static int hash64k(int i) {
return (i * -1640531535) >>> ((MIN_MATCH * 8) - HASH_LOG_64K);
}
static int hashHC(int i) {
return (i * -1640531535) >>> ((MIN_MATCH * 8) - HASH_LOG_HC);
}
static class Match {
int start, ref, len;
void fix(int correction) {
start += correction;
ref += correction;
len -= correction;
}
int end() {
return start + len;
}
}
static void copyTo(Match m1, Match m2) {
m2.len = m1.len;
m2.start = m1.start;
m2.ref = m1.ref;
}
}