Migrated source code from Simantics SVN

[simantics/platform.git] / bundles / org.simantics.lz4 / src / net / jpountz / lz4 / LZ4Utils.java

diff --git a/bundles/org.simantics.lz4/src/net/jpountz/lz4/LZ4Utils.java b/bundles/org.simantics.lz4/src/net/jpountz/lz4/LZ4Utils.java
new file mode 100644 (file)
index 0000000..5661c41
--- /dev/null
+++ b/bundles/org.simantics.lz4/src/net/jpountz/lz4/LZ4Utils.java
@@ -0,0 +1,68 @@
+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.MIN_MATCH;
+
+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;
+  }
+
+}