/*
* Copyright (c) 2007, 2016, 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 if (opt == SO_REUSEPORT) {
// SO_REUSEPORT is not supported on Windows.
throw new UnsupportedOperationException("unsupported option");
} 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 if (opt == SO_REUSEPORT) {
// SO_REUSEPORT is not supported on Windows.
throw new UnsupportedOperationException("unsupported option");
}
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;
}