/*
* Copyright 2001-2006 Sun Microsystems, Inc. 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. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package sun.nio.ch;
import java.io.FileDescriptor;
import java.io.IOException;
import java.net.*;
import java.nio.ByteBuffer;
import java.nio.channels.*;
import java.nio.channels.spi.*;
import java.lang.ref.SoftReference;
/**
* An implementation of DatagramChannels.
*/
class DatagramChannelImpl
extends DatagramChannel
implements SelChImpl
{
// Used to make native read and write calls
private static NativeDispatcher nd = new DatagramDispatcher();
// Our file descriptor
FileDescriptor fd = null;
// fd value needed for dev/poll. This value will remain valid
// even after the value in the file descriptor object has been set to -1
int fdVal;
// IDs of native threads doing reads and writes, for signalling
private volatile long readerThread = 0;
private volatile long writerThread = 0;
// Cached InetAddress and port for unconnected DatagramChannels
// used by receive0
private InetAddress cachedSenderInetAddress = null;
private int cachedSenderPort = 0;
// Lock held by current reading or connecting thread
private final Object readLock = new Object();
// Lock held by current writing or connecting thread
private final Object writeLock = new Object();
// Lock held by any thread that modifies the state fields declared below
// DO NOT invoke a blocking I/O operation while holding this lock!
private final Object stateLock = new Object();
// -- The following fields are protected by stateLock
// State (does not necessarily increase monotonically)
private static final int ST_UNINITIALIZED = -1;
private static int ST_UNCONNECTED = 0;
private static int ST_CONNECTED = 1;
private static final int ST_KILLED = 2;
private int state = ST_UNINITIALIZED;
// Binding
private SocketAddress localAddress = null;
SocketAddress remoteAddress = null;
// Options
private SocketOpts.IP options = null;
// Our socket adaptor, if any
private DatagramSocket socket = null;
// -- End of fields protected by stateLock
public DatagramChannelImpl(SelectorProvider sp)
throws IOException
{
super(sp);
this.fd = Net.socket(false);
this.fdVal = IOUtil.fdVal(fd);
this.state = ST_UNCONNECTED;
}
public DatagramChannelImpl(SelectorProvider sp, FileDescriptor fd)
throws IOException
{
super(sp);
this.fd = fd;
this.fdVal = IOUtil.fdVal(fd);
this.state = ST_UNCONNECTED;
}
public DatagramSocket socket() {
synchronized (stateLock) {
if (socket == null)
socket = DatagramSocketAdaptor.create(this);
return socket;
}
}
private void ensureOpen() throws ClosedChannelException {
if (!isOpen())
throw new ClosedChannelException();
}
private SocketAddress sender; // Set by receive0 (## ugh)
public SocketAddress receive(ByteBuffer dst) throws IOException {
if (dst.isReadOnly())
throw new IllegalArgumentException("Read-only buffer");
if (dst == null)
throw new NullPointerException();
synchronized (readLock) {
ensureOpen();
// If socket is not bound then behave as if nothing received
if (!isBound()) // ## NotYetBoundException ??
return null;
int n = 0;
ByteBuffer bb = null;
try {
begin();
if (!isOpen())
return null;
SecurityManager security = System.getSecurityManager();
readerThread = NativeThread.current();
if (isConnected() || (security == null)) {
do {
n = receive(fd, dst);
} while ((n == IOStatus.INTERRUPTED) && isOpen());
if (n == IOStatus.UNAVAILABLE)
return null;
} else {
bb = Util.getTemporaryDirectBuffer(dst.remaining());
for (;;) {
do {
n = receive(fd, bb);
} while ((n == IOStatus.INTERRUPTED) && isOpen());
if (n == IOStatus.UNAVAILABLE)
return null;
InetSocketAddress isa = (InetSocketAddress)sender;
try {
security.checkAccept(
isa.getAddress().getHostAddress(),
isa.getPort());
} catch (SecurityException se) {
// Ignore packet
bb.clear();
n = 0;
continue;
}
bb.flip();
dst.put(bb);
break;
}
}
return sender;
} finally {
if (bb != null)
Util.releaseTemporaryDirectBuffer(bb);
readerThread = 0;
end((n > 0) || (n == IOStatus.UNAVAILABLE));
assert IOStatus.check(n);
}
}
}
private int receive(FileDescriptor fd, ByteBuffer dst)
throws IOException
{
int pos = dst.position();
int lim = dst.limit();
assert (pos <= lim);
int rem = (pos <= lim ? lim - pos : 0);
if (dst instanceof DirectBuffer && rem > 0)
return receiveIntoNativeBuffer(fd, dst, rem, pos);
// Substitute a native buffer. If the supplied buffer is empty
// we must instead use a nonempty buffer, otherwise the call
// will not block waiting for a datagram on some platforms.
int newSize = Math.max(rem, 1);
ByteBuffer bb = null;
try {
bb = Util.getTemporaryDirectBuffer(newSize);
int n = receiveIntoNativeBuffer(fd, bb, newSize, 0);
bb.flip();
if (n > 0 && rem > 0)
dst.put(bb);
return n;
} finally {
Util.releaseTemporaryDirectBuffer(bb);
}
}
private int receiveIntoNativeBuffer(FileDescriptor fd, ByteBuffer bb,
int rem, int pos)
throws IOException
{
int n = receive0(fd, ((DirectBuffer)bb).address() + pos, rem,
isConnected());
if (n > 0)
bb.position(pos + n);
return n;
}
public int send(ByteBuffer src, SocketAddress target)
throws IOException
{
if (src == null)
throw new NullPointerException();
synchronized (writeLock) {
ensureOpen();
InetSocketAddress isa = (InetSocketAddress)target;
InetAddress ia = isa.getAddress();
if (ia == null)
throw new IOException("Target address not resolved");
synchronized (stateLock) {
if (!isConnected()) {
if (target == null)
throw new NullPointerException();
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
if (ia.isMulticastAddress()) {
sm.checkMulticast(isa.getAddress());
} else {
sm.checkConnect(isa.getAddress().getHostAddress(),
isa.getPort());
}
}
} else { // Connected case; Check address then write
if (!target.equals(remoteAddress)) {
throw new IllegalArgumentException(
"Connected address not equal to target address");
}
return write(src);
}
}
int n = 0;
try {
begin();
if (!isOpen())
return 0;
writerThread = NativeThread.current();
do {
n = send(fd, src, target);
} while ((n == IOStatus.INTERRUPTED) && isOpen());
return IOStatus.normalize(n);
} finally {
writerThread = 0;
end((n > 0) || (n == IOStatus.UNAVAILABLE));
assert IOStatus.check(n);
}
}
}
private int send(FileDescriptor fd, ByteBuffer src, SocketAddress target)
throws IOException
{
if (src instanceof DirectBuffer)
return sendFromNativeBuffer(fd, src, target);
// Substitute a native buffer
int pos = src.position();
int lim = src.limit();
assert (pos <= lim);
int rem = (pos <= lim ? lim - pos : 0);
ByteBuffer bb = null;
try {
bb = Util.getTemporaryDirectBuffer(rem);
bb.put(src);
bb.flip();
// Do not update src until we see how many bytes were written
src.position(pos);
int n = sendFromNativeBuffer(fd, bb, target);
if (n > 0) {
// now update src
src.position(pos + n);
}
return n;
} finally {
Util.releaseTemporaryDirectBuffer(bb);
}
}
private int sendFromNativeBuffer(FileDescriptor fd, ByteBuffer bb,
SocketAddress target)
throws IOException
{
int pos = bb.position();
int lim = bb.limit();
assert (pos <= lim);
int rem = (pos <= lim ? lim - pos : 0);
int written = send0(fd, ((DirectBuffer)bb).address() + pos,
rem, target);
if (written > 0)
bb.position(pos + written);
return written;
}
public int read(ByteBuffer buf) throws IOException {
if (buf == null)
throw new NullPointerException();
synchronized (readLock) {
synchronized (stateLock) {
ensureOpen();
if (!isConnected())
throw new NotYetConnectedException();
}
int n = 0;
try {
begin();
if (!isOpen())
return 0;
readerThread = NativeThread.current();
do {
n = IOUtil.read(fd, buf, -1, nd, readLock);
} while ((n == IOStatus.INTERRUPTED) && isOpen());
return IOStatus.normalize(n);
} finally {
readerThread = 0;
end((n > 0) || (n == IOStatus.UNAVAILABLE));
assert IOStatus.check(n);
}
}
}
private long read0(ByteBuffer[] bufs) throws IOException {
if (bufs == null)
throw new NullPointerException();
synchronized (readLock) {
synchronized (stateLock) {
ensureOpen();
if (!isConnected())
throw new NotYetConnectedException();
}
long n = 0;
try {
begin();
if (!isOpen())
return 0;
readerThread = NativeThread.current();
do {
n = IOUtil.read(fd, bufs, nd);
} while ((n == IOStatus.INTERRUPTED) && isOpen());
return IOStatus.normalize(n);
} finally {
readerThread = 0;
end((n > 0) || (n == IOStatus.UNAVAILABLE));
assert IOStatus.check(n);
}
}
}
public long read(ByteBuffer[] dsts, int offset, int length)
throws IOException
{
if ((offset < 0) || (length < 0) || (offset > dsts.length - length))
throw new IndexOutOfBoundsException();
// ## Fix IOUtil.write so that we can avoid this array copy
return read0(Util.subsequence(dsts, offset, length));
}
public int write(ByteBuffer buf) throws IOException {
if (buf == null)
throw new NullPointerException();
synchronized (writeLock) {
synchronized (stateLock) {
ensureOpen();
if (!isConnected())
throw new NotYetConnectedException();
}
int n = 0;
try {
begin();
if (!isOpen())
return 0;
writerThread = NativeThread.current();
do {
n = IOUtil.write(fd, buf, -1, nd, writeLock);
} while ((n == IOStatus.INTERRUPTED) && isOpen());
return IOStatus.normalize(n);
} finally {
writerThread = 0;
end((n > 0) || (n == IOStatus.UNAVAILABLE));
assert IOStatus.check(n);
}
}
}
private long write0(ByteBuffer[] bufs) throws IOException {
if (bufs == null)
throw new NullPointerException();
synchronized (writeLock) {
synchronized (stateLock) {
ensureOpen();
if (!isConnected())
throw new NotYetConnectedException();
}
long n = 0;
try {
begin();
if (!isOpen())
return 0;
writerThread = NativeThread.current();
do {
n = IOUtil.write(fd, bufs, nd);
} while ((n == IOStatus.INTERRUPTED) && isOpen());
return IOStatus.normalize(n);
} finally {
writerThread = 0;
end((n > 0) || (n == IOStatus.UNAVAILABLE));
assert IOStatus.check(n);
}
}
}
public long write(ByteBuffer[] srcs, int offset, int length)
throws IOException
{
if ((offset < 0) || (length < 0) || (offset > srcs.length - length))
throw new IndexOutOfBoundsException();
// ## Fix IOUtil.write so that we can avoid this array copy
return write0(Util.subsequence(srcs, offset, length));
}
protected void implConfigureBlocking(boolean block) throws IOException {
IOUtil.configureBlocking(fd, block);
}
public SocketOpts options() {
synchronized (stateLock) {
if (options == null) {
SocketOptsImpl.Dispatcher d
= new SocketOptsImpl.Dispatcher() {
int getInt(int opt) throws IOException {
return Net.getIntOption(fd, opt);
}
void setInt(int opt, int arg)
throws IOException
{
Net.setIntOption(fd, opt, arg);
}
};
options = new SocketOptsImpl.IP(d);
}
return options;
}
}
public boolean isBound() {
return Net.localPortNumber(fd) != 0;
}
public SocketAddress localAddress() {
synchronized (stateLock) {
if (isConnected() && (localAddress == null)) {
// Socket was not bound before connecting,
// so ask what the address turned out to be
localAddress = Net.localAddress(fd);
}
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
InetSocketAddress isa = (InetSocketAddress)localAddress;
sm.checkConnect(isa.getAddress().getHostAddress(), -1);
}
return localAddress;
}
}
public SocketAddress remoteAddress() {
synchronized (stateLock) {
return remoteAddress;
}
}
public void bind(SocketAddress local) throws IOException {
synchronized (readLock) {
synchronized (writeLock) {
synchronized (stateLock) {
ensureOpen();
if (isBound())
throw new AlreadyBoundException();
InetSocketAddress isa = Net.checkAddress(local);
SecurityManager sm = System.getSecurityManager();
if (sm != null)
sm.checkListen(isa.getPort());
Net.bind(fd, isa.getAddress(), isa.getPort());
localAddress = Net.localAddress(fd);
}
}
}
}
public boolean isConnected() {
synchronized (stateLock) {
return (state == ST_CONNECTED);
}
}
void ensureOpenAndUnconnected() throws IOException { // package-private
synchronized (stateLock) {
if (!isOpen())
throw new ClosedChannelException();
if (state != ST_UNCONNECTED)
throw new IllegalStateException("Connect already invoked");
}
}
public DatagramChannel connect(SocketAddress sa) throws IOException {
int trafficClass = 0;
int localPort = 0;
synchronized(readLock) {
synchronized(writeLock) {
synchronized (stateLock) {
ensureOpenAndUnconnected();
InetSocketAddress isa = Net.checkAddress(sa);
SecurityManager sm = System.getSecurityManager();
if (sm != null)
sm.checkConnect(isa.getAddress().getHostAddress(),
isa.getPort());
int n = Net.connect(fd,
isa.getAddress(),
isa.getPort(),
trafficClass);
if (n <= 0)
throw new Error(); // Can't happen
// Connection succeeded; disallow further invocation
state = ST_CONNECTED;
remoteAddress = sa;
sender = isa;
cachedSenderInetAddress = isa.getAddress();
cachedSenderPort = isa.getPort();
}
}
}
return this;
}
public DatagramChannel disconnect() throws IOException {
synchronized(readLock) {
synchronized(writeLock) {
synchronized (stateLock) {
if (!isConnected() || !isOpen())
return this;
InetSocketAddress isa = (InetSocketAddress)remoteAddress;
SecurityManager sm = System.getSecurityManager();
if (sm != null)
sm.checkConnect(isa.getAddress().getHostAddress(),
isa.getPort());
disconnect0(fd);
remoteAddress = null;
state = ST_UNCONNECTED;
}
}
}
return this;
}
protected void implCloseSelectableChannel() throws IOException {
synchronized (stateLock) {
nd.preClose(fd);
long th;
if ((th = readerThread) != 0)
NativeThread.signal(th);
if ((th = writerThread) != 0)
NativeThread.signal(th);
if (!isRegistered())
kill();
}
}
public void kill() throws IOException {
synchronized (stateLock) {
if (state == ST_KILLED)
return;
if (state == ST_UNINITIALIZED) {
state = ST_KILLED;
return;
}
assert !isOpen() && !isRegistered();
nd.close(fd);
state = ST_KILLED;
}
}
protected void finalize() throws IOException {
// fd is null if constructor threw exception
if (fd != null)
close();
}
/**
* Translates native poll revent set into a ready operation set
*/
public boolean translateReadyOps(int ops, int initialOps,
SelectionKeyImpl sk) {
int intOps = sk.nioInterestOps(); // Do this just once, it synchronizes
int oldOps = sk.nioReadyOps();
int newOps = initialOps;
if ((ops & PollArrayWrapper.POLLNVAL) != 0) {
// This should only happen if this channel is pre-closed while a
// selection operation is in progress
// ## Throw an error if this channel has not been pre-closed
return false;
}
if ((ops & (PollArrayWrapper.POLLERR
| PollArrayWrapper.POLLHUP)) != 0) {
newOps = intOps;
sk.nioReadyOps(newOps);
return (newOps & ~oldOps) != 0;
}
if (((ops & PollArrayWrapper.POLLIN) != 0) &&
((intOps & SelectionKey.OP_READ) != 0))
newOps |= SelectionKey.OP_READ;
if (((ops & PollArrayWrapper.POLLOUT) != 0) &&
((intOps & SelectionKey.OP_WRITE) != 0))
newOps |= SelectionKey.OP_WRITE;
sk.nioReadyOps(newOps);
return (newOps & ~oldOps) != 0;
}
public boolean translateAndUpdateReadyOps(int ops, SelectionKeyImpl sk) {
return translateReadyOps(ops, sk.nioReadyOps(), sk);
}
public boolean translateAndSetReadyOps(int ops, SelectionKeyImpl sk) {
return translateReadyOps(ops, 0, sk);
}
/**
* Translates an interest operation set into a native poll event set
*/
public void translateAndSetInterestOps(int ops, SelectionKeyImpl sk) {
int newOps = 0;
if ((ops & SelectionKey.OP_READ) != 0)
newOps |= PollArrayWrapper.POLLIN;
if ((ops & SelectionKey.OP_WRITE) != 0)
newOps |= PollArrayWrapper.POLLOUT;
if ((ops & SelectionKey.OP_CONNECT) != 0)
newOps |= PollArrayWrapper.POLLIN;
sk.selector.putEventOps(sk, newOps);
}
public FileDescriptor getFD() {
return fd;
}
public int getFDVal() {
return fdVal;
}
// -- Native methods --
private static native void initIDs();
private static native void disconnect0(FileDescriptor fd)
throws IOException;
private native int receive0(FileDescriptor fd, long address, int len,
boolean connected)
throws IOException;
private native int send0(FileDescriptor fd, long address, int len,
SocketAddress sa)
throws IOException;
static {
Util.load();
initIDs();
}
}