1 /*
   2  * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test
  26  * @requires vm.compMode != "Xcomp"
  27  * @summary Verifies behaviour of Unsafe.allocateMemory
  28  * @library /test/lib
  29  * @modules java.base/jdk.internal.misc
  30  *          java.management
  31  * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:MallocMaxTestWords=100m AllocateMemory
  32  */
  33 
  34 import jdk.test.lib.unsafe.UnsafeHelper;
  35 import jdk.internal.misc.Unsafe;
  36 import static jdk.test.lib.Asserts.*;
  37 
  38 public class AllocateMemory {
  39     public static void main(String args[]) throws Exception {
  40         Unsafe unsafe = UnsafeHelper.getUnsafe();
  41 
  42         // Allocate a byte, write to the location and read back the value
  43         long address = unsafe.allocateMemory(1);
  44         assertNotEquals(address, 0L);
  45 
  46         unsafe.putByte(address, Byte.MAX_VALUE);
  47         assertEquals(Byte.MAX_VALUE, unsafe.getByte(address));
  48         unsafe.freeMemory(address);
  49 
  50         // Call to allocateMemory() with a negative value should result in an IllegalArgumentException
  51         try {
  52             address = unsafe.allocateMemory(-1);
  53             throw new RuntimeException("Did not get expected IllegalArgumentException");
  54         } catch (IllegalArgumentException e) {
  55             // Expected
  56             assertNotEquals(address, 0L);
  57         }
  58 
  59         // allocateMemory() should throw an OutOfMemoryError when the underlying malloc fails,
  60         // we test this by limiting the malloc using -XX:MallocMaxTestWords
  61         try {
  62             address = unsafe.allocateMemory(100 * 1024 * 1024 * 8);
  63         } catch (OutOfMemoryError e) {
  64             // Expected
  65             return;
  66         }
  67         throw new RuntimeException("Did not get expected OutOfMemoryError");
  68     }
  69 }