/* * Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.net; import java.io.IOException; import java.io.FileDescriptor; import sun.net.ResourceManager; /* * This class defines the plain SocketImpl that is used for all * Windows version lower than Vista. It adds support for IPv6 on * these platforms where available. * * For backward compatibility Windows platforms that do not have IPv6 * support also use this implementation, and fd1 gets set to null * during socket creation. * * @author Chris Hegarty */ class TwoStacksPlainSocketImpl extends AbstractPlainSocketImpl { /* second fd, used for ipv6 on windows only. * fd1 is used for listeners and for client sockets at initialization * until the socket is connected. Up to this point fd always refers * to the ipv4 socket and fd1 to the ipv6 socket. After the socket * becomes connected, fd always refers to the connected socket * (either v4 or v6) and fd1 is closed. * * For ServerSockets, fd always refers to the v4 listener and * fd1 the v6 listener. */ private FileDescriptor fd1; /* * Needed for ipv6 on windows because we need to know * if the socket is bound to ::0 or 0.0.0.0, when a caller * asks for it. Otherwise we don't know which socket to ask. */ private InetAddress anyLocalBoundAddr = null; /* to prevent starvation when listening on two sockets, this is * is used to hold the id of the last socket we accepted on. */ private int lastfd = -1; // true if this socket is exclusively bound private final boolean exclusiveBind; // emulates SO_REUSEADDR when exclusiveBind is true private boolean isReuseAddress; static { initProto(); } public TwoStacksPlainSocketImpl(boolean exclBind) { exclusiveBind = exclBind; } public TwoStacksPlainSocketImpl(FileDescriptor fd, boolean exclBind) { this.fd = fd; exclusiveBind = exclBind; } /** * Creates a socket with a boolean that specifies whether this * is a stream socket (true) or an unconnected UDP socket (false). */ protected synchronized void create(boolean stream) throws IOException { fd1 = new FileDescriptor(); try { super.create(stream); } catch (IOException e) { fd1 = null; throw e; } } /** * Binds the socket to the specified address of the specified local port. * @param address the address * @param port the port */ protected synchronized void bind(InetAddress address, int lport) throws IOException { super.bind(address, lport); if (address.isAnyLocalAddress()) { anyLocalBoundAddr = address; } } public Object getOption(int opt) throws SocketException { if (isClosedOrPending()) { throw new SocketException("Socket Closed"); } if (opt == SO_BINDADDR) { if (fd != null && fd1 != null ) { /* must be unbound or else bound to anyLocal */ return anyLocalBoundAddr; } InetAddressContainer in = new InetAddressContainer(); socketGetOption(opt, in); return in.addr; } else if (opt == SO_REUSEADDR && exclusiveBind) { // SO_REUSEADDR emulated when using exclusive bind return isReuseAddress; } else return super.getOption(opt); } @Override void socketBind(InetAddress address, int port) throws IOException { socketBind(address, port, exclusiveBind); } @Override void socketSetOption(int opt, boolean on, Object value) throws SocketException { // SO_REUSEADDR emulated when using exclusive bind if (opt == SO_REUSEADDR && exclusiveBind) isReuseAddress = on; else socketNativeSetOption(opt, on, value); } /** * Closes the socket. */ @Override protected void close() throws IOException { synchronized(fdLock) { if (fd != null || fd1 != null) { if (!stream) { ResourceManager.afterUdpClose(); } if (fdUseCount == 0) { if (closePending) { return; } closePending = true; socketClose(); fd = null; fd1 = null; return; } else { /* * If a thread has acquired the fd and a close * isn't pending then use a deferred close. * Also decrement fdUseCount to signal the last * thread that releases the fd to close it. */ if (!closePending) { closePending = true; fdUseCount--; socketClose(); } } } } } @Override void reset() throws IOException { if (fd != null || fd1 != null) { socketClose(); } fd = null; fd1 = null; super.reset(); } /* * Return true if already closed or close is pending */ @Override public boolean isClosedOrPending() { /* * Lock on fdLock to ensure that we wait if a * close is in progress. */ synchronized (fdLock) { if (closePending || (fd == null && fd1 == null)) { return true; } else { return false; } } } /* Native methods */ static native void initProto(); native void socketCreate(boolean isServer) throws IOException; native void socketConnect(InetAddress address, int port, int timeout) throws IOException; native void socketBind(InetAddress address, int port, boolean exclBind) throws IOException; native void socketListen(int count) throws IOException; native void socketAccept(SocketImpl s) throws IOException; native int socketAvailable() throws IOException; native void socketClose0(boolean useDeferredClose) throws IOException; native void socketShutdown(int howto) throws IOException; native void socketNativeSetOption(int cmd, boolean on, Object value) throws SocketException; native int socketGetOption(int opt, Object iaContainerObj) throws SocketException; native void socketSendUrgentData(int data) throws IOException; }