1 /*
 2  * Copyright (c) 2021, 2023, 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  * @enablePreview
27  * @requires jdk.foreign.linker != "UNSUPPORTED"
28  * @run testng/othervm
29  *     --enable-native-access=ALL-UNNAMED
30  *     TestNULLAddress
31  */
32 
33 import org.testng.annotations.Test;
34 
35 import java.lang.foreign.Linker;
36 import java.lang.foreign.FunctionDescriptor;
37 import java.lang.foreign.MemorySegment;
38 import java.lang.foreign.SymbolLookup;
39 import java.lang.foreign.ValueLayout;
40 import java.lang.invoke.MethodHandle;
41 
42 import static org.testng.Assert.*;
43 
44 public class TestNULLAddress {
45 
46     static {
47         System.loadLibrary("Null");
48     }
49 
50     static final Linker LINKER = Linker.nativeLinker();
51 
52     @Test(expectedExceptions = IllegalArgumentException.class)
53     public void testNULLLinking() {
54         LINKER.downcallHandle(
55                 MemorySegment.NULL,
56                 FunctionDescriptor.ofVoid());
57     }
58 
59     @Test(expectedExceptions = IllegalArgumentException.class)
60     public void testNULLVirtual() throws Throwable {
61         MethodHandle mh = LINKER.downcallHandle(
62                 FunctionDescriptor.ofVoid());
63         mh.invokeExact(MemorySegment.NULL);
64     }
65 
66     @Test
67     public void testNULLReturn_target() throws Throwable {
68         MethodHandle mh = LINKER.downcallHandle(SymbolLookup.loaderLookup().find("get_null").get(),
69                 FunctionDescriptor.of(ValueLayout.ADDRESS.withTargetLayout(ValueLayout.JAVA_INT)));
70         MemorySegment ret = (MemorySegment)mh.invokeExact();
71         assertTrue(ret.equals(MemorySegment.NULL));
72     }
73 
74     @Test
75     public void testNULLReturn_plain() throws Throwable {
76         MethodHandle mh = LINKER.downcallHandle(SymbolLookup.loaderLookup().find("get_null").get(),
77                 FunctionDescriptor.of(ValueLayout.ADDRESS));
78         MemorySegment ret = (MemorySegment)mh.invokeExact();
79         assertTrue(ret.equals(MemorySegment.NULL));
80     }
81 }