Add test for MemoryUnmapper

h2/src/test/org/h2/test/TestAll.java

@@ -193,6 +193,7 @@ import org.h2.test.unit.TestIntPerfectHash;
 import org.h2.test.unit.TestJmx;
 import org.h2.test.unit.TestLocale;
 import org.h2.test.unit.TestMathUtils;
+import org.h2.test.unit.TestMemoryUnmapper;
 import org.h2.test.unit.TestMode;
 import org.h2.test.unit.TestModifyOnWrite;
 import org.h2.test.unit.TestNetUtils;
@@ -960,6 +961,7 @@ kill -9 `jps -l | grep "org.h2.test." | cut -d " " -f 1`
         addTest(new TestIntIntHashMap());
         addTest(new TestIntPerfectHash());
         addTest(new TestMathUtils());
+        addTest(new TestMemoryUnmapper());
         addTest(new TestMode());
         addTest(new TestObjectDeserialization());
         addTest(new TestOverflow());

h2/src/test/org/h2/test/unit/TestMemoryUnmapper.java

+/*
+ * Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
+ * and the EPL 1.0 (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.test.unit;
+
+import java.lang.ProcessBuilder.Redirect;
+import java.nio.ByteBuffer;
+
+import org.h2.test.TestBase;
+import org.h2.util.MemoryUnmapper;
+
+/**
+ * Tests memory unmapper.
+ */
+public class TestMemoryUnmapper extends TestBase {
+    private static final int OK = 0, /* EXCEPTION = 1, */ UNAVAILABLE = 2;
+
+    /**
+     * May be used to run only this test and may be launched by this test in a
+     * subprocess.
+     *
+     * @param a
+     *            if empty run this test only
+     */
+    public static void main(String... a) throws Exception {
+        if (a.length == 0) {
+            TestBase.createCaller().init().test();
+        } else {
+            ByteBuffer buffer = ByteBuffer.allocateDirect(10);
+            System.exit(MemoryUnmapper.unmap(buffer) ? OK : UNAVAILABLE);
+        }
+    }
+
+    @Override
+    public void test() throws Exception {
+        ProcessBuilder pb = new ProcessBuilder().redirectError(Redirect.INHERIT);
+        // Test that unsafe unmapping is disabled by default
+        pb.command(getJVM(), "-cp", getClassPath(), "-ea", getClass().getName(), "dummy");
+        assertEquals(UNAVAILABLE, pb.start().waitFor());
+        // Test that it can be enabled
+        pb.command(getJVM(), "-cp", getClassPath(), "-ea", "-Dh2.nioCleanerHack=true", getClass().getName(), "dummy");
+        assertEquals(OK, pb.start().waitFor());
+        // Test that it will not be enabled with a security manager
+        pb.command(getJVM(), "-cp", getClassPath(), "-ea", "-Djava.security.manager", "-Dh2.nioCleanerHack=true",
+                getClass().getName(), "dummy");
+        assertEquals(UNAVAILABLE, pb.start().waitFor());
+    }
+
+}