1 /*
   2  * Copyright (c) 2010, 2018, 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.  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
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.net.sdp;
  27 
  28 import java.io.IOException;
  29 import java.io.FileDescriptor;
  30 import java.security.AccessController;
  31 
  32 import jdk.internal.access.SharedSecrets;
  33 import jdk.internal.access.JavaIOFileDescriptorAccess;
  34 import sun.security.action.GetPropertyAction;
  35 
  36 
  37 /**
  38  * This class defines methods for creating SDP sockets or "converting" existing
  39  * file descriptors, referencing (unbound) TCP sockets, to SDP.
  40  */
  41 
  42 public final class SdpSupport {
  43     private static final String os = GetPropertyAction.privilegedGetProperty("os.name");
  44     private static final boolean isSupported = (os.equals("SunOS") || (os.equals("Linux")));
  45     private static final JavaIOFileDescriptorAccess fdAccess =
  46         SharedSecrets.getJavaIOFileDescriptorAccess();
  47 
  48     private SdpSupport() { }
  49 
  50     /**
  51      * Creates a SDP socket, returning file descriptor referencing the socket.
  52      */
  53     public static FileDescriptor createSocket() throws IOException {
  54         if (!isSupported)
  55             throw new UnsupportedOperationException("SDP not supported on this platform");
  56         int fdVal = create0();
  57         FileDescriptor fd = new FileDescriptor();
  58         fdAccess.set(fd, fdVal);
  59         return fd;
  60     }
  61 
  62     /**
  63      * Converts an existing file descriptor, that references an unbound TCP socket,
  64      * to SDP.
  65      */
  66     public static void convertSocket(FileDescriptor fd) throws IOException {
  67         if (!isSupported)
  68             throw new UnsupportedOperationException("SDP not supported on this platform");
  69         int fdVal = fdAccess.get(fd);
  70         convert0(fdVal);
  71     }
  72 
  73     private static native int create0() throws IOException;
  74 
  75     private static native void convert0(int fd) throws IOException;
  76 
  77     static {
  78         AccessController.doPrivileged(
  79             new java.security.PrivilegedAction<Void>() {
  80                 public Void run() {
  81                     System.loadLibrary("net");
  82                     return null;
  83                 }
  84             });
  85     }
  86 }