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
 6  * under the terms of the GNU General Public License version 2 only, as
 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.
10  *
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).
16  *
17  * You should have received a copy of the GNU General Public License version
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19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
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22  * or visit www.oracle.com if you need additional information or have any
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24  */
25 
26 package sun.nio.ch;
27 
28 import java.io.FileDescriptor;
29 import java.io.IOException;
30 
31 abstract class UnixDispatcher extends NativeDispatcher {
32     private static final boolean SUPPORTS_PENDING_SIGNALS = NativeThread.supportPendingSignals();
33 
34     @Override
35     void close(FileDescriptor fd) throws IOException {
36         close0(fd);
37     }
38 
39     private void signalThreads(Thread reader, Thread writer) {
40         if (reader != null) {
41             NativeThread.signal(reader);
42         }
43         if (writer != null) {
44             NativeThread.signal(writer);
45         }
46     }
47 
48     @Override
49     void implPreClose(FileDescriptor fd, Thread reader, Thread writer) throws IOException {
50         if (SUPPORTS_PENDING_SIGNALS) {
51             signalThreads(reader, writer);
52         }
53         preClose0(fd);
54         if (!SUPPORTS_PENDING_SIGNALS) {
55             signalThreads(reader, writer);
56         }
57     }
58 
59     private static native void close0(FileDescriptor fd) throws IOException;
60 
61     private static native void preClose0(FileDescriptor fd) throws IOException;
62 
63     static native void init();
64 
65     static {
66         IOUtil.load();
67         init();
68     }
69 }