1 /*
2 * Copyright (c) 1995, 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 java.net;
27
28 import java.io.FileDescriptor;
29 import java.io.IOException;
30 import java.io.InputStream;
31 import java.io.OutputStream;
32
33 import java.security.AccessController;
34 import java.security.PrivilegedActionException;
35 import java.security.PrivilegedExceptionAction;
36 import java.util.Collections;
37 import java.util.HashSet;
38 import java.util.Objects;
39 import java.util.Set;
40
41 import sun.net.ConnectionResetException;
42 import sun.net.NetHooks;
43 import sun.net.PlatformSocketImpl;
44 import sun.net.ResourceManager;
45 import sun.net.ext.ExtendedSocketOptions;
46 import sun.net.util.IPAddressUtil;
47 import sun.net.util.SocketExceptions;
48
49 /**
50 * Default Socket Implementation. This implementation does
51 * not implement any security checks.
52 * Note this class should <b>NOT</b> be public.
53 *
54 * @author Steven B. Byrne
55 */
56 abstract class AbstractPlainSocketImpl extends SocketImpl implements PlatformSocketImpl {
57 /* instance variable for SO_TIMEOUT */
58 int timeout; // timeout in millisec
59 // traffic class
60 private int trafficClass;
61
62 private boolean shut_rd = false;
63 private boolean shut_wr = false;
64
65 private SocketInputStream socketInputStream = null;
66 private SocketOutputStream socketOutputStream = null;
67
68 /* number of threads using the FileDescriptor */
69 protected int fdUseCount = 0;
70
71 /* lock when increment/decrementing fdUseCount */
72 protected final Object fdLock = new Object();
73
74 /* indicates a close is pending on the file descriptor */
75 protected boolean closePending = false;
76
77 /* indicates connection reset state */
78 private volatile boolean connectionReset;
79
80 /* indicates whether impl is bound */
81 boolean isBound;
82
83 /* indicates whether impl is connected */
84 volatile boolean isConnected;
85
86 /* whether this Socket is a stream (TCP) socket or not (UDP)
87 */
88 protected boolean stream;
89
90 /* whether this is a server or not */
91 final boolean isServer;
92
93 /**
94 * Load net library into runtime.
95 */
96 static {
97 jdk.internal.loader.BootLoader.loadLibrary("net");
98 }
99
100 private static volatile boolean checkedReusePort;
101 private static volatile boolean isReusePortAvailable;
102
103 /**
104 * Tells whether SO_REUSEPORT is supported.
105 */
106 static boolean isReusePortAvailable() {
107 if (!checkedReusePort) {
108 isReusePortAvailable = isReusePortAvailable0();
109 checkedReusePort = true;
110 }
111 return isReusePortAvailable;
112 }
113
114 AbstractPlainSocketImpl(boolean isServer) {
115 this.isServer = isServer;
116 }
117
118 /**
119 * Creates a socket with a boolean that specifies whether this
120 * is a stream socket (true) or an unconnected UDP socket (false).
121 */
122 protected synchronized void create(boolean stream) throws IOException {
123 this.stream = stream;
124 if (!stream) {
125 ResourceManager.beforeUdpCreate();
126 // only create the fd after we know we will be able to create the socket
127 fd = new FileDescriptor();
128 try {
129 socketCreate(false);
130 SocketCleanable.register(fd, false);
131 } catch (IOException ioe) {
132 ResourceManager.afterUdpClose();
133 fd = null;
134 throw ioe;
135 }
136 } else {
137 fd = new FileDescriptor();
138 socketCreate(true);
139 SocketCleanable.register(fd, true);
140 }
141 }
142
143 /**
144 * Creates a socket and connects it to the specified port on
145 * the specified host.
146 * @param host the specified host
147 * @param port the specified port
148 */
149 protected void connect(String host, int port)
150 throws UnknownHostException, IOException
151 {
152 boolean connected = false;
153 try {
154 InetAddress address = InetAddress.getByName(host);
155 // recording this.address as supplied by caller before calling connect
156 this.address = address;
157 this.port = port;
158 if (address.isLinkLocalAddress()) {
159 address = IPAddressUtil.toScopedAddress(address);
160 }
161
162 connectToAddress(address, port, timeout);
163 connected = true;
164 } finally {
165 if (!connected) {
166 try {
167 close();
168 } catch (IOException ioe) {
169 /* Do nothing. If connect threw an exception then
170 it will be passed up the call stack */
171 }
172 }
173 isConnected = connected;
174 }
175 }
176
177 /**
178 * Creates a socket and connects it to the specified address on
179 * the specified port.
180 * @param address the address
181 * @param port the specified port
182 */
183 protected void connect(InetAddress address, int port) throws IOException {
184 // recording this.address as supplied by caller before calling connect
185 this.address = address;
186 this.port = port;
187 if (address.isLinkLocalAddress()) {
188 address = IPAddressUtil.toScopedAddress(address);
189 }
190
191 try {
192 connectToAddress(address, port, timeout);
193 isConnected = true;
194 return;
195 } catch (IOException e) {
196 // everything failed
197 close();
198 throw e;
199 }
200 }
201
202 /**
203 * Creates a socket and connects it to the specified address on
204 * the specified port.
205 * @param address the address
206 * @param timeout the timeout value in milliseconds, or zero for no timeout.
207 * @throws IOException if connection fails
208 * @throws IllegalArgumentException if address is null or is a
209 * SocketAddress subclass not supported by this socket
210 * @since 1.4
211 */
212 protected void connect(SocketAddress address, int timeout)
213 throws IOException {
214 boolean connected = false;
215 try {
216 if (address == null || !(address instanceof InetSocketAddress))
217 throw new IllegalArgumentException("unsupported address type");
218 InetSocketAddress addr = (InetSocketAddress) address;
219 if (addr.isUnresolved())
220 throw new UnknownHostException(addr.getHostName());
221 // recording this.address as supplied by caller before calling connect
222 InetAddress ia = addr.getAddress();
223 this.address = ia;
224 this.port = addr.getPort();
225 if (ia.isLinkLocalAddress()) {
226 ia = IPAddressUtil.toScopedAddress(ia);
227 }
228 connectToAddress(ia, port, timeout);
229 connected = true;
230 } finally {
231 if (!connected) {
232 try {
233 close();
234 } catch (IOException ioe) {
235 /* Do nothing. If connect threw an exception then
236 it will be passed up the call stack */
237 }
238 }
239 isConnected = connected;
240 }
241 }
242
243 private void connectToAddress(InetAddress address, int port, int timeout) throws IOException {
244 if (address.isAnyLocalAddress()) {
245 doConnect(InetAddress.getLocalHost(), port, timeout);
246 } else {
247 doConnect(address, port, timeout);
248 }
249 }
250
251 public void setOption(int opt, Object val) throws SocketException {
252 if (isClosedOrPending()) {
253 throw new SocketException("Socket Closed");
254 }
255 boolean on = true;
256 switch (opt) {
257 /* check type safety b4 going native. These should never
258 * fail, since only java.Socket* has access to
259 * PlainSocketImpl.setOption().
260 */
261 case SO_LINGER:
262 if (val == null || (!(val instanceof Integer) && !(val instanceof Boolean)))
263 throw new SocketException("Bad parameter for option");
264 if (val instanceof Boolean) {
265 /* true only if disabling - enabling should be Integer */
266 on = false;
267 }
268 break;
269 case SO_TIMEOUT:
270 if (val == null || (!(val instanceof Integer)))
271 throw new SocketException("Bad parameter for SO_TIMEOUT");
272 int tmp = ((Integer) val).intValue();
273 if (tmp < 0)
274 throw new IllegalArgumentException("timeout < 0");
275 timeout = tmp;
276 break;
277 case IP_TOS:
278 if (val == null || !(val instanceof Integer)) {
279 throw new SocketException("bad argument for IP_TOS");
280 }
281 trafficClass = ((Integer)val).intValue();
282 break;
283 case SO_BINDADDR:
284 throw new SocketException("Cannot re-bind socket");
285 case TCP_NODELAY:
286 if (val == null || !(val instanceof Boolean))
287 throw new SocketException("bad parameter for TCP_NODELAY");
288 on = ((Boolean)val).booleanValue();
289 break;
290 case SO_SNDBUF:
291 case SO_RCVBUF:
292 if (val == null || !(val instanceof Integer) ||
293 !(((Integer)val).intValue() > 0)) {
294 throw new SocketException("bad parameter for SO_SNDBUF " +
295 "or SO_RCVBUF");
296 }
297 break;
298 case SO_KEEPALIVE:
299 if (val == null || !(val instanceof Boolean))
300 throw new SocketException("bad parameter for SO_KEEPALIVE");
301 on = ((Boolean)val).booleanValue();
302 break;
303 case SO_OOBINLINE:
304 if (val == null || !(val instanceof Boolean))
305 throw new SocketException("bad parameter for SO_OOBINLINE");
306 on = ((Boolean)val).booleanValue();
307 break;
308 case SO_REUSEADDR:
309 if (val == null || !(val instanceof Boolean))
310 throw new SocketException("bad parameter for SO_REUSEADDR");
311 on = ((Boolean)val).booleanValue();
312 break;
313 case SO_REUSEPORT:
314 if (val == null || !(val instanceof Boolean))
315 throw new SocketException("bad parameter for SO_REUSEPORT");
316 if (!supportedOptions().contains(StandardSocketOptions.SO_REUSEPORT))
317 throw new UnsupportedOperationException("unsupported option");
318 on = ((Boolean)val).booleanValue();
319 break;
320 default:
321 throw new SocketException("unrecognized TCP option: " + opt);
322 }
323 socketSetOption(opt, on, val);
324 }
325 public Object getOption(int opt) throws SocketException {
326 if (isClosedOrPending()) {
327 throw new SocketException("Socket Closed");
328 }
329 if (opt == SO_TIMEOUT) {
330 return timeout;
331 }
332 int ret = 0;
333 /*
334 * The native socketGetOption() knows about 3 options.
335 * The 32 bit value it returns will be interpreted according
336 * to what we're asking. A return of -1 means it understands
337 * the option but its turned off. It will raise a SocketException
338 * if "opt" isn't one it understands.
339 */
340
341 switch (opt) {
342 case TCP_NODELAY:
343 ret = socketGetOption(opt, null);
344 return Boolean.valueOf(ret != -1);
345 case SO_OOBINLINE:
346 ret = socketGetOption(opt, null);
347 return Boolean.valueOf(ret != -1);
348 case SO_LINGER:
349 ret = socketGetOption(opt, null);
350 return (ret == -1) ? Boolean.FALSE: (Object)(ret);
351 case SO_REUSEADDR:
352 ret = socketGetOption(opt, null);
353 return Boolean.valueOf(ret != -1);
354 case SO_BINDADDR:
355 InetAddressContainer in = new InetAddressContainer();
356 ret = socketGetOption(opt, in);
357 return in.addr;
358 case SO_SNDBUF:
359 case SO_RCVBUF:
360 ret = socketGetOption(opt, null);
361 return ret;
362 case IP_TOS:
363 try {
364 ret = socketGetOption(opt, null);
365 if (ret == -1) { // ipv6 tos
366 return trafficClass;
367 } else {
368 return ret;
369 }
370 } catch (SocketException se) {
371 // TODO - should make better effort to read TOS or TCLASS
372 return trafficClass; // ipv6 tos
373 }
374 case SO_KEEPALIVE:
375 ret = socketGetOption(opt, null);
376 return Boolean.valueOf(ret != -1);
377 case SO_REUSEPORT:
378 if (!supportedOptions().contains(StandardSocketOptions.SO_REUSEPORT)) {
379 throw new UnsupportedOperationException("unsupported option");
380 }
381 ret = socketGetOption(opt, null);
382 return Boolean.valueOf(ret != -1);
383 // should never get here
384 default:
385 return null;
386 }
387 }
388
389 static final ExtendedSocketOptions extendedOptions =
390 ExtendedSocketOptions.getInstance();
391
392 private static final Set<SocketOption<?>> clientSocketOptions = clientSocketOptions();
393 private static final Set<SocketOption<?>> serverSocketOptions = serverSocketOptions();
394
395 private static Set<SocketOption<?>> clientSocketOptions() {
396 HashSet<SocketOption<?>> options = new HashSet<>();
397 options.add(StandardSocketOptions.SO_KEEPALIVE);
398 options.add(StandardSocketOptions.SO_SNDBUF);
399 options.add(StandardSocketOptions.SO_RCVBUF);
400 options.add(StandardSocketOptions.SO_REUSEADDR);
401 options.add(StandardSocketOptions.SO_LINGER);
402 options.add(StandardSocketOptions.IP_TOS);
403 options.add(StandardSocketOptions.TCP_NODELAY);
404 if (isReusePortAvailable())
405 options.add(StandardSocketOptions.SO_REUSEPORT);
406 options.addAll(ExtendedSocketOptions.clientSocketOptions());
407 return Collections.unmodifiableSet(options);
408 }
409
410 private static Set<SocketOption<?>> serverSocketOptions() {
411 HashSet<SocketOption<?>> options = new HashSet<>();
412 options.add(StandardSocketOptions.SO_RCVBUF);
413 options.add(StandardSocketOptions.SO_REUSEADDR);
414 options.add(StandardSocketOptions.IP_TOS);
415 if (isReusePortAvailable())
416 options.add(StandardSocketOptions.SO_REUSEPORT);
417 options.addAll(ExtendedSocketOptions.serverSocketOptions());
418 return Collections.unmodifiableSet(options);
419 }
420
421 @Override
422 protected Set<SocketOption<?>> supportedOptions() {
423 if (isServer)
424 return serverSocketOptions;
425 else
426 return clientSocketOptions;
427 }
428
429 @Override
430 protected <T> void setOption(SocketOption<T> name, T value) throws IOException {
431 Objects.requireNonNull(name);
432 if (!supportedOptions().contains(name))
433 throw new UnsupportedOperationException("'" + name + "' not supported");
434
435 if (!name.type().isInstance(value))
436 throw new IllegalArgumentException("Invalid value '" + value + "'");
437
438 if (isClosedOrPending())
439 throw new SocketException("Socket closed");
440
441 if (name == StandardSocketOptions.SO_KEEPALIVE) {
442 setOption(SocketOptions.SO_KEEPALIVE, value);
443 } else if (name == StandardSocketOptions.SO_SNDBUF) {
444 if (((Integer)value).intValue() < 0)
445 throw new IllegalArgumentException("Invalid send buffer size:" + value);
446 setOption(SocketOptions.SO_SNDBUF, value);
447 } else if (name == StandardSocketOptions.SO_RCVBUF) {
448 if (((Integer)value).intValue() < 0)
449 throw new IllegalArgumentException("Invalid recv buffer size:" + value);
450 setOption(SocketOptions.SO_RCVBUF, value);
451 } else if (name == StandardSocketOptions.SO_REUSEADDR) {
452 setOption(SocketOptions.SO_REUSEADDR, value);
453 } else if (name == StandardSocketOptions.SO_REUSEPORT) {
454 setOption(SocketOptions.SO_REUSEPORT, value);
455 } else if (name == StandardSocketOptions.SO_LINGER ) {
456 if (((Integer)value).intValue() < 0)
457 setOption(SocketOptions.SO_LINGER, false);
458 else
459 setOption(SocketOptions.SO_LINGER, value);
460 } else if (name == StandardSocketOptions.IP_TOS) {
461 int i = ((Integer)value).intValue();
462 if (i < 0 || i > 255)
463 throw new IllegalArgumentException("Invalid IP_TOS value: " + value);
464 setOption(SocketOptions.IP_TOS, value);
465 } else if (name == StandardSocketOptions.TCP_NODELAY) {
466 setOption(SocketOptions.TCP_NODELAY, value);
467 } else if (extendedOptions.isOptionSupported(name)) {
468 extendedOptions.setOption(fd, name, value);
469 } else {
470 throw new AssertionError("unknown option: " + name);
471 }
472 }
473
474 @Override
475 @SuppressWarnings("unchecked")
476 protected <T> T getOption(SocketOption<T> name) throws IOException {
477 Objects.requireNonNull(name);
478 if (!supportedOptions().contains(name))
479 throw new UnsupportedOperationException("'" + name + "' not supported");
480
481 if (isClosedOrPending())
482 throw new SocketException("Socket closed");
483
484 if (name == StandardSocketOptions.SO_KEEPALIVE) {
485 return (T)getOption(SocketOptions.SO_KEEPALIVE);
486 } else if (name == StandardSocketOptions.SO_SNDBUF) {
487 return (T)getOption(SocketOptions.SO_SNDBUF);
488 } else if (name == StandardSocketOptions.SO_RCVBUF) {
489 return (T)getOption(SocketOptions.SO_RCVBUF);
490 } else if (name == StandardSocketOptions.SO_REUSEADDR) {
491 return (T)getOption(SocketOptions.SO_REUSEADDR);
492 } else if (name == StandardSocketOptions.SO_REUSEPORT) {
493 return (T)getOption(SocketOptions.SO_REUSEPORT);
494 } else if (name == StandardSocketOptions.SO_LINGER) {
495 Object value = getOption(SocketOptions.SO_LINGER);
496 if (value instanceof Boolean) {
497 assert ((Boolean)value).booleanValue() == false;
498 value = -1;
499 }
500 return (T)value;
501 } else if (name == StandardSocketOptions.IP_TOS) {
502 return (T)getOption(SocketOptions.IP_TOS);
503 } else if (name == StandardSocketOptions.TCP_NODELAY) {
504 return (T)getOption(SocketOptions.TCP_NODELAY);
505 } else if (extendedOptions.isOptionSupported(name)) {
506 return (T) extendedOptions.getOption(fd, name);
507 } else {
508 throw new AssertionError("unknown option: " + name);
509 }
510 }
511
512 /**
513 * The workhorse of the connection operation. Tries several times to
514 * establish a connection to the given <host, port>. If unsuccessful,
515 * throws an IOException indicating what went wrong.
516 */
517
518 synchronized void doConnect(InetAddress address, int port, int timeout) throws IOException {
519 synchronized (fdLock) {
520 if (!closePending && !isBound) {
521 NetHooks.beforeTcpConnect(fd, address, port);
522 }
523 }
524 try {
525 acquireFD();
526 try {
527 socketConnect(address, port, timeout);
528 /* socket may have been closed during poll/select */
529 synchronized (fdLock) {
530 if (closePending) {
531 throw new SocketException ("Socket closed");
532 }
533 }
534 } finally {
535 releaseFD();
536 }
537 } catch (IOException e) {
538 close();
539 throw SocketExceptions.of(e, new InetSocketAddress(address, port));
540 }
541 }
542
543 /**
544 * Binds the socket to the specified address of the specified local port.
545 * @param address the address
546 * @param lport the port
547 */
548 protected synchronized void bind(InetAddress address, int lport)
549 throws IOException
550 {
551 synchronized (fdLock) {
552 if (!closePending && !isBound) {
553 NetHooks.beforeTcpBind(fd, address, lport);
554 }
555 }
556 if (address.isLinkLocalAddress()) {
557 address = IPAddressUtil.toScopedAddress(address);
558 }
559 socketBind(address, lport);
560 isBound = true;
561 }
562
563 /**
564 * Listens, for a specified amount of time, for connections.
565 * @param count the amount of time to listen for connections
566 */
567 protected synchronized void listen(int count) throws IOException {
568 socketListen(count);
569 }
570
571 /**
572 * Accepts connections.
573 * @param si the socket impl
574 */
575 protected void accept(SocketImpl si) throws IOException {
576 si.fd = new FileDescriptor();
577 acquireFD();
578 try {
579 socketAccept(si);
580 } finally {
581 releaseFD();
582 }
583 SocketCleanable.register(si.fd, true);
584 }
585
586 /**
587 * Gets an InputStream for this socket.
588 */
589 protected synchronized InputStream getInputStream() throws IOException {
590 synchronized (fdLock) {
591 if (isClosedOrPending())
592 throw new IOException("Socket Closed");
593 if (shut_rd)
594 throw new IOException("Socket input is shutdown");
595 if (socketInputStream == null) {
596 PrivilegedExceptionAction<SocketInputStream> pa = () -> new SocketInputStream(this);
597 try {
598 socketInputStream = AccessController.doPrivileged(pa);
599 } catch (PrivilegedActionException e) {
600 throw (IOException) e.getCause();
601 }
602 }
603 }
604 return socketInputStream;
605 }
606
607 void setInputStream(SocketInputStream in) {
608 socketInputStream = in;
609 }
610
611 /**
612 * Gets an OutputStream for this socket.
613 */
614 protected synchronized OutputStream getOutputStream() throws IOException {
615 synchronized (fdLock) {
616 if (isClosedOrPending())
617 throw new IOException("Socket Closed");
618 if (shut_wr)
619 throw new IOException("Socket output is shutdown");
620 if (socketOutputStream == null) {
621 PrivilegedExceptionAction<SocketOutputStream> pa = () -> new SocketOutputStream(this);
622 try {
623 socketOutputStream = AccessController.doPrivileged(pa);
624 } catch (PrivilegedActionException e) {
625 throw (IOException) e.getCause();
626 }
627 }
628 }
629 return socketOutputStream;
630 }
631
632 void setFileDescriptor(FileDescriptor fd) {
633 this.fd = fd;
634 }
635
636 void setAddress(InetAddress address) {
637 this.address = address;
638 }
639
640 void setPort(int port) {
641 this.port = port;
642 }
643
644 void setLocalPort(int localport) {
645 this.localport = localport;
646 }
647
648 /**
649 * Returns the number of bytes that can be read without blocking.
650 */
651 protected synchronized int available() throws IOException {
652 if (isClosedOrPending()) {
653 throw new IOException("Stream closed.");
654 }
655
656 /*
657 * If connection has been reset or shut down for input, then return 0
658 * to indicate there are no buffered bytes.
659 */
660 if (isConnectionReset() || shut_rd) {
661 return 0;
662 }
663
664 /*
665 * If no bytes available and we were previously notified
666 * of a connection reset then we move to the reset state.
667 *
668 * If are notified of a connection reset then check
669 * again if there are bytes buffered on the socket.
670 */
671 int n = 0;
672 try {
673 n = socketAvailable();
674 } catch (ConnectionResetException exc1) {
675 setConnectionReset();
676 }
677 return n;
678 }
679
680 /**
681 * Closes the socket.
682 */
683 protected void close() throws IOException {
684 synchronized(fdLock) {
685 if (fd != null) {
686 if (fdUseCount == 0) {
687 if (closePending) {
688 return;
689 }
690 closePending = true;
691 /*
692 * We close the FileDescriptor in two-steps - first the
693 * "pre-close" which closes the socket but doesn't
694 * release the underlying file descriptor. This operation
695 * may be lengthy due to untransmitted data and a long
696 * linger interval. Once the pre-close is done we do the
697 * actual socket to release the fd.
698 */
699 try {
700 socketPreClose();
701 } finally {
702 socketClose();
703 }
704 fd = null;
705 return;
706 } else {
707 /*
708 * If a thread has acquired the fd and a close
709 * isn't pending then use a deferred close.
710 * Also decrement fdUseCount to signal the last
711 * thread that releases the fd to close it.
712 */
713 if (!closePending) {
714 closePending = true;
715 fdUseCount--;
716 socketPreClose();
717 }
718 }
719 }
720 }
721 }
722
723 void reset() {
724 throw new InternalError("should not get here");
725 }
726
727 /**
728 * Shutdown read-half of the socket connection;
729 */
730 protected void shutdownInput() throws IOException {
731 if (fd != null) {
732 socketShutdown(SHUT_RD);
733 if (socketInputStream != null) {
734 socketInputStream.setEOF(true);
735 }
736 shut_rd = true;
737 }
738 }
739
740 /**
741 * Shutdown write-half of the socket connection;
742 */
743 protected void shutdownOutput() throws IOException {
744 if (fd != null) {
745 socketShutdown(SHUT_WR);
746 shut_wr = true;
747 }
748 }
749
750 protected boolean supportsUrgentData () {
751 return true;
752 }
753
754 protected void sendUrgentData (int data) throws IOException {
755 if (fd == null) {
756 throw new IOException("Socket Closed");
757 }
758 socketSendUrgentData (data);
759 }
760
761 /*
762 * "Acquires" and returns the FileDescriptor for this impl
763 *
764 * A corresponding releaseFD is required to "release" the
765 * FileDescriptor.
766 */
767 FileDescriptor acquireFD() {
768 synchronized (fdLock) {
769 fdUseCount++;
770 return fd;
771 }
772 }
773
774 /*
775 * "Release" the FileDescriptor for this impl.
776 *
777 * If the use count goes to -1 then the socket is closed.
778 */
779 void releaseFD() {
780 synchronized (fdLock) {
781 fdUseCount--;
782 if (fdUseCount == -1) {
783 if (fd != null) {
784 try {
785 socketClose();
786 } catch (IOException e) {
787 } finally {
788 fd = null;
789 }
790 }
791 }
792 }
793 }
794
795 boolean isConnectionReset() {
796 return connectionReset;
797 }
798
799 void setConnectionReset() {
800 connectionReset = true;
801 }
802
803 /*
804 * Return true if already closed or close is pending
805 */
806 public boolean isClosedOrPending() {
807 /*
808 * Lock on fdLock to ensure that we wait if a
809 * close is in progress.
810 */
811 synchronized (fdLock) {
812 if (closePending || (fd == null)) {
813 return true;
814 } else {
815 return false;
816 }
817 }
818 }
819
820 /*
821 * Return the current value of SO_TIMEOUT
822 */
823 public int getTimeout() {
824 return timeout;
825 }
826
827 /*
828 * "Pre-close" a socket by dup'ing the file descriptor - this enables
829 * the socket to be closed without releasing the file descriptor.
830 */
831 private void socketPreClose() throws IOException {
832 socketClose0(true);
833 }
834
835 /*
836 * Close the socket (and release the file descriptor).
837 */
838 protected void socketClose() throws IOException {
839 SocketCleanable.unregister(fd);
840 try {
841 socketClose0(false);
842 } finally {
843 if (!stream) {
844 ResourceManager.afterUdpClose();
845 }
846 }
847 }
848
849 abstract void socketCreate(boolean stream) throws IOException;
850 abstract void socketConnect(InetAddress address, int port, int timeout)
851 throws IOException;
852 abstract void socketBind(InetAddress address, int port)
853 throws IOException;
854 abstract void socketListen(int count)
855 throws IOException;
856 abstract void socketAccept(SocketImpl s)
857 throws IOException;
858 abstract int socketAvailable()
859 throws IOException;
860 abstract void socketClose0(boolean useDeferredClose)
861 throws IOException;
862 abstract void socketShutdown(int howto)
863 throws IOException;
864 abstract void socketSetOption(int cmd, boolean on, Object value)
865 throws SocketException;
866 abstract int socketGetOption(int opt, Object iaContainerObj) throws SocketException;
867 abstract void socketSendUrgentData(int data)
868 throws IOException;
869
870 public static final int SHUT_RD = 0;
871 public static final int SHUT_WR = 1;
872
873 private static native boolean isReusePortAvailable0();
874 }