[Java] Add CRC-32 and CRC-32C checksums.

agrona/src/main/java/org/agrona/checksum/Checksum.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2014-2024 Real Logic Limited.
+ *
+ * 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
+ *
+ * https://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.
+ */
+package org.agrona.checksum;
+
+/**
+ * An interface representing API to compute a data checksum.
+ * <p>
+ * <b>Note:</b> Instances should be threadsafe and stateless.
+ */
+@FunctionalInterface
+public interface Checksum
+{
+    /**
+     * Computes a checksum based on the contents of a {@code java.nio.DirectByteBuffer}.
+     *
+     * @param address of the buffer.
+     * @param offset  within the buffer to begin at.
+     * @param length  of the data to read.
+     * @return computed checksum value.
+     */
+    int compute(long address, int offset, int length);
+}

agrona/src/main/java/org/agrona/checksum/Crc32.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2014-2024 Real Logic Limited.
+ *
+ * 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
+ *
+ * https://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.
+ */
+package org.agrona.checksum;
+
+import org.agrona.LangUtil;
+
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.reflect.Method;
+import java.util.zip.CRC32;
+
+/**
+ * Implementation of the {@link Checksum} interface that computes CRC-32 checksum.
+ */
+public final class Crc32 implements Checksum
+{
+    /**
+     * Singleton instance to compute CRC-32 checksum.
+     */
+    public static final Crc32 INSTANCE = new Crc32();
+
+    private static final MethodHandle UPDATE_BYTE_BUFFER;
+
+    static
+    {
+        try
+        {
+            final Method method =
+                CRC32.class.getDeclaredMethod("updateByteBuffer0", int.class, long.class, int.class, int.class);
+            method.setAccessible(true);
+            MethodHandle methodHandle = MethodHandles.lookup().unreflect(method);
+            methodHandle = MethodHandles.insertArguments(methodHandle, 0, 0);
+            UPDATE_BYTE_BUFFER = methodHandle;
+        }
+        catch (final Exception ex)
+        {
+            throw new Error(ex);
+        }
+    }
+
+    private Crc32()
+    {
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public int compute(final long address, final int offset, final int length)
+    {
+        try
+        {
+            return (int)UPDATE_BYTE_BUFFER.invokeExact(address, offset, length);
+        }
+        catch (final Throwable t)
+        {
+            LangUtil.rethrowUnchecked(t);
+            return -1;
+        }
+    }
+}

agrona/src/main/java/org/agrona/checksum/Crc32c.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright 2014-2024 Real Logic Limited.
+ *
+ * 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
+ *
+ * https://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.
+ */
+package org.agrona.checksum;
+
+import org.agrona.LangUtil;
+
+import java.lang.invoke.MethodHandle;
+import java.lang.reflect.Method;
+import java.util.zip.CRC32C;
+
+import static java.lang.invoke.MethodHandles.*;
+import static java.lang.invoke.MethodType.methodType;
+
+/**
+ * Implementation of the {@link Checksum} interface that computes CRC-32C checksum.
+ *
+ * <p>
+ * CRC-32C is defined in <a href="http://www.ietf.org/rfc/rfc3720.txt">RFC 3720</a>:
+ * Internet Small Computer Systems Interface (iSCSI).
+ * </p>
+ */
+public final class Crc32c implements Checksum
+{
+    /**
+     * Single instance to compute CRC-32C checksum.
+     */
+    public static final Crc32c INSTANCE = new Crc32c();
+
+    private static final MethodHandle UPDATE_DIRECT_BYTE_BUFFER;
+
+    static
+    {
+        MethodHandle methodHandle;
+        try
+        {
+            final Method method = CRC32C.class.getDeclaredMethod(
+                "updateDirectByteBuffer", int.class, long.class, int.class, int.class);
+            method.setAccessible(true);
+            final Lookup lookup = lookup();
+            methodHandle = lookup.unreflect(method);
+            final MethodHandle bitwiseComplement = lookup.findStatic(
+                Crc32c.class, "bitwiseComplement", methodType(int.class, int.class));
+            // Always invoke with the 0xFFFFFFFF as first argument, i.e. empty CRC value
+            methodHandle = insertArguments(methodHandle, 0, 0xFFFFFFFF);
+            // Always compute bitwise complement on the result value
+            methodHandle = filterReturnValue(methodHandle, bitwiseComplement);
+        }
+        catch (final Exception ex)
+        {
+            throw new Error(ex);
+        }
+
+        UPDATE_DIRECT_BYTE_BUFFER = methodHandle;
+    }
+
+    private static int bitwiseComplement(final int value)
+    {
+        return ~value;
+    }
+
+    private Crc32c()
+    {
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public int compute(final long address, final int offset, final int length)
+    {
+        try
+        {
+            return (int)UPDATE_DIRECT_BYTE_BUFFER.invokeExact(address, offset, offset + length /* end */);
+        }
+        catch (final Throwable t)
+        {
+            LangUtil.rethrowUnchecked(t);
+            return -1;
+        }
+    }
+}

agrona/src/test/java/org/agrona/checksum/Crc32Test.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2014-2024 Real Logic Limited.
+ *
+ * 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
+ *
+ * https://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.
+ */
+package org.agrona.checksum;
+
+import org.junit.jupiter.api.Test;
+
+import java.nio.ByteBuffer;
+import java.util.Random;
+import java.util.zip.CRC32;
+
+import static org.agrona.BufferUtil.address;
+import static org.junit.jupiter.api.Assertions.*;
+
+class Crc32Test
+{
+    @Test
+    void compute()
+    {
+        final Random random = new Random(-1234);
+        final int offset = 3;
+        final ByteBuffer buffer = ByteBuffer.allocateDirect(1024 + offset);
+        final long address = address(buffer);
+        for (int i = 1; i <= 1024; i++)
+        {
+            final int length = i;
+            final byte[] data = new byte[length];
+            random.nextBytes(data);
+            buffer.clear().position(offset);
+            buffer.put(data);
+            buffer.flip().position(offset);
+            final CRC32 crc32 = new CRC32();
+            crc32.update(buffer);
+            final int checksum = (int)crc32.getValue();
+            assertEquals(
+                checksum, Crc32.INSTANCE.compute(address, offset, length), () -> "Failed on length: " + length);
+        }
+    }
+}

agrona/src/test/java/org/agrona/checksum/Crc32cTest.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2014-2024 Real Logic Limited.
+ *
+ * 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
+ *
+ * https://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.
+ */
+package org.agrona.checksum;
+
+import org.junit.jupiter.api.Test;
+
+import java.nio.ByteBuffer;
+import java.util.Random;
+import java.util.zip.CRC32C;
+
+import static org.agrona.BufferUtil.address;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+class Crc32cTest
+{
+    @Test
+    void compute()
+    {
+        final Random random = new Random(54893045794L);
+        final int offset = 7;
+        final ByteBuffer buffer = ByteBuffer.allocateDirect(1024 + offset);
+        final long address = address(buffer);
+
+        for (int i = 1; i <= 1024; i++)
+        {
+            final int length = i;
+            final byte[] data = new byte[length];
+            random.nextBytes(data);
+            buffer.clear().position(offset);
+            buffer.put(data);
+            buffer.flip().position(offset);
+            final CRC32C crc32c = new CRC32C();
+            crc32c.update(buffer);
+            final int checksum = (int)crc32c.getValue();
+            assertEquals(
+                checksum, Crc32c.INSTANCE.compute(address, offset, length), () -> "Failed on length: " + length);
+        }
+    }
+}

build.gradle

@@ -204,6 +204,7 @@ subprojects {
 
     test {
         jvmArgs('--add-opens', 'java.base/jdk.internal.misc=ALL-UNNAMED')
+        jvmArgs('--add-opens', 'java.base/java.util.zip=ALL-UNNAMED')
 
         if (buildJavaVersion >= 21) {
             jvmArgs('-XX:+EnableDynamicAgentLoading')