1 /*
   2  * Copyright (c) 2010, 2019, 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 
  31 import jdk.internal.access.SharedSecrets;
  32 import jdk.internal.access.JavaIOFileDescriptorAccess;
  33 import sun.security.action.GetPropertyAction;
  34 
  35 
  36 /**
  37  * This class defines methods for creating SDP sockets or "converting" existing
  38  * file descriptors, referencing (unbound) TCP sockets, to SDP.
  39  */
  40 
  41 public final class SdpSupport {
  42     private static final String os = GetPropertyAction.privilegedGetProperty("os.name");
  43     private static final boolean isSupported = (os.equals("SunOS") || (os.equals("Linux")));
  44     private static final JavaIOFileDescriptorAccess fdAccess =
  45         SharedSecrets.getJavaIOFileDescriptorAccess();
  46 
  47     private SdpSupport() { }
  48 
  49     /**
  50      * Creates a SDP socket, returning file descriptor referencing the socket.
  51      */
  52     public static FileDescriptor createSocket() throws IOException {
  53         if (!isSupported)
  54             throw new UnsupportedOperationException("SDP not supported on this platform");
  55         int fdVal = create0();
  56         FileDescriptor fd = new FileDescriptor();
  57         fdAccess.set(fd, fdVal);
  58         return fd;
  59     }
  60 
  61     /**
  62      * Converts an existing file descriptor, that references an unbound TCP socket,
  63      * to SDP.
  64      */
  65     public static void convertSocket(FileDescriptor fd) throws IOException {
  66         if (!isSupported)
  67             throw new UnsupportedOperationException("SDP not supported on this platform");
  68         int fdVal = fdAccess.get(fd);
  69         convert0(fdVal);
  70     }
  71 
  72     private static native int create0() throws IOException;
  73 
  74     private static native void convert0(int fd) throws IOException;
  75 
  76     static {
  77         jdk.internal.loader.BootLoader.loadLibrary("net");
  78     }
  79 }