1 /*
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 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
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 7  * published by the Free Software Foundation.  Oracle designates this
 8  * particular file as subject to the "Classpath" exception as provided
 9  * by Oracle in the LICENSE file that accompanied this code.
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11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
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24  */
25 package jdk.internal.foreign.abi;
26 
27 import java.lang.foreign.MemorySegment;
28 import java.lang.foreign.Arena;
29 
30 import jdk.internal.foreign.MemorySessionImpl;
31 
32 public final class UpcallStubs {
33 
34     private UpcallStubs() {
35     }
36 
37     private static void freeUpcallStub(long stubAddress) {
38         if (!freeUpcallStub0(stubAddress)) {
39             throw new IllegalStateException("Not a stub address: " + stubAddress);
40         }
41     }
42 
43     // natives
44 
45     // returns true if the stub was found (and freed)
46     private static native boolean freeUpcallStub0(long addr);
47 
48     private static native void registerNatives();
49     static {
50         registerNatives();
51     }
52 
53     static MemorySegment makeUpcall(long entry, Arena arena) {
54         MemorySessionImpl.toMemorySession(arena).addOrCleanupIfFail(new MemorySessionImpl.ResourceList.ResourceCleanup() {
55             @Override
56             public void cleanup() {
57                 freeUpcallStub(entry);
58             }
59         });
60         return MemorySegment.ofAddress(entry).reinterpret(arena, null);
61     }
62 }