src/java.base/solaris/classes/sun/nio/ch/EventPortSelectorImpl.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 2012, 2018, 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 sun.nio.ch;

 import java.io.IOException;
 import java.nio.channels.ClosedSelectorException;
 import java.nio.channels.SelectionKey;
 import java.nio.channels.Selector;
 import java.nio.channels.spi.SelectorProvider;
 import java.util.ArrayDeque;
 import java.util.Deque;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Consumer;

 import static sun.nio.ch.SolarisEventPort.PORT_SOURCE_FD;
 import static sun.nio.ch.SolarisEventPort.PORT_SOURCE_USER;
 import static sun.nio.ch.SolarisEventPort.SIZEOF_PORT_EVENT;
 import static sun.nio.ch.SolarisEventPort.OFFSETOF_EVENTS;
 import static sun.nio.ch.SolarisEventPort.OFFSETOF_SOURCE;
 import static sun.nio.ch.SolarisEventPort.OFFSETOF_OBJECT;
 import static sun.nio.ch.SolarisEventPort.port_create;
 import static sun.nio.ch.SolarisEventPort.port_close;
 import static sun.nio.ch.SolarisEventPort.port_associate;
 import static sun.nio.ch.SolarisEventPort.port_dissociate;
 import static sun.nio.ch.SolarisEventPort.port_getn;
 import static sun.nio.ch.SolarisEventPort.port_send;

 /**
  * Selector implementation based on the Solaris event port mechanism.
  */

 class EventPortSelectorImpl
     extends SelectorImpl
 {
     // maximum number of events to retrive in one call to port_getn
     static final int MAX_EVENTS = Math.min(IOUtil.fdLimit()-1, 1024);

     // port file descriptor
     private final int pfd;

     // the poll array (populated by port_getn)
     private final long pollArrayAddress;
     private final AllocatedNativeObject pollArray;

     // maps file descriptor to selection key, synchronize on selector
     private final Map<Integer, SelectionKeyImpl> fdToKey = new HashMap<>();

     // the last update operation, incremented by processUpdateQueue
     private int lastUpdate;

     // pending new registrations/updates, queued by setEventOps and
     // updateSelectedKeys
     private final Object updateLock = new Object();
     private final Deque<SelectionKeyImpl> updateKeys = new ArrayDeque<>();

     // interrupt triggering and clearing
     private final Object interruptLock = new Object();
     private boolean interruptTriggered;

     EventPortSelectorImpl(SelectorProvider sp) throws IOException {
         super(sp);

         this.pfd = port_create();

         int allocationSize = MAX_EVENTS * SIZEOF_PORT_EVENT;
         this.pollArray = new AllocatedNativeObject(allocationSize, false);
         this.pollArrayAddress = pollArray.address();
     }

     private void ensureOpen() {
         if (!isOpen())
             throw new ClosedSelectorException();
     }

     @Override
     protected int doSelect(Consumer<SelectionKey> action, long timeout)
         throws IOException
     {
         assert Thread.holdsLock(this);

         long to = timeout;
         boolean blocking = (to != 0);
         boolean timedPoll = (to > 0);

         int numEvents;
         processUpdateQueue();
         processDeregisterQueue();
         try {
             begin(blocking);

             do {
                 long startTime = timedPoll ? System.nanoTime() : 0;
                 numEvents = port_getn(pfd, pollArrayAddress, MAX_EVENTS, to);
                 if (numEvents == IOStatus.INTERRUPTED && timedPoll) {
                     // timed poll interrupted so need to adjust timeout
                     long adjust = System.nanoTime() - startTime;
                     to -= TimeUnit.MILLISECONDS.convert(adjust, TimeUnit.NANOSECONDS);
                     if (to <= 0) {
                         // timeout also expired so no retry
                         numEvents = 0;
                     }
                 }
             } while (numEvents == IOStatus.INTERRUPTED);
             assert IOStatus.check(numEvents);

         } finally {
             end(blocking);
         }
         processDeregisterQueue();
         return processPortEvents(numEvents, action);
     }

     /**
      * Process new registrations and changes to the interest ops.
      */
     private void processUpdateQueue() throws IOException {
         assert Thread.holdsLock(this);

         // bump lastUpdate to ensure that the interest ops are changed at most
         // once per bulk update
         lastUpdate++;

         synchronized (updateLock) {
             SelectionKeyImpl ski;
             while ((ski = updateKeys.pollFirst()) != null) {
                 if (ski.isValid()) {
                     int fd = ski.getFDVal();
                     // add to fdToKey if needed
                     SelectionKeyImpl previous = fdToKey.putIfAbsent(fd, ski);
                     assert (previous == null) || (previous == ski);

                     int newEvents = ski.translateInterestOps();
                     if (newEvents != ski.registeredEvents()) {
                         if (newEvents == 0) {
                             port_dissociate(pfd, PORT_SOURCE_FD, fd);
                         } else {
                             port_associate(pfd, PORT_SOURCE_FD, fd, newEvents);
                         }
                         ski.registeredEvents(newEvents);
                     }
                 }
             }
         }
     }

     /**
      * Process the polled events and re-queue the selected keys so the file
      * descriptors are re-associated at the next select operation.
      */
     private int processPortEvents(int numEvents, Consumer<SelectionKey> action)
         throws IOException
     {
         assert Thread.holdsLock(this);

         int numKeysUpdated = 0;
         boolean interrupted = false;

         // Process the polled events while holding the update lock. This allows
         // keys to be queued for ready file descriptors so they can be
         // re-associated at the next select. The selected-key can be updated
         // in this pass.
         synchronized (updateLock) {
             for (int i = 0; i < numEvents; i++) {
                 short source = getSource(i);
                 if (source == PORT_SOURCE_FD) {
                     int fd = getDescriptor(i);
                     SelectionKeyImpl ski = fdToKey.get(fd);
                     if (ski != null) {
                         ski.registeredEvents(0);
                         updateKeys.addLast(ski);

                         // update selected-key set if no action specified
                         if (action == null) {
                             int rOps = getEventOps(i);
                             numKeysUpdated += processReadyEvents(rOps, ski, null);
                         }

                     }
                 } else if (source == PORT_SOURCE_USER) {
                     interrupted = true;
                 } else {
                     assert false;
                 }
             }
         }

         // if an action specified then iterate over the polled events again so
         // that the action is performed without holding the update lock.
         if (action != null) {
             for (int i = 0; i < numEvents; i++) {
                 short source = getSource(i);
                 if (source == PORT_SOURCE_FD) {
                     int fd = getDescriptor(i);
                     SelectionKeyImpl ski = fdToKey.get(fd);
                     if (ski != null) {
                         int rOps = getEventOps(i);
                         numKeysUpdated += processReadyEvents(rOps, ski, action);
                     }
                 }
             }
         }

         if (interrupted) {
             clearInterrupt();
         }
         return numKeysUpdated;
     }

     @Override
     protected void implClose() throws IOException {
         assert !isOpen();
         assert Thread.holdsLock(this);

         // prevent further wakeup
         synchronized (interruptLock) {
             interruptTriggered = true;
         }

         port_close(pfd);
         pollArray.free();
     }

     @Override
     protected void implDereg(SelectionKeyImpl ski) throws IOException {
         assert !ski.isValid();
         assert Thread.holdsLock(this);

         int fd = ski.getFDVal();
         if (fdToKey.remove(fd) != null) {
             if (ski.registeredEvents() != 0) {
                 port_dissociate(pfd, PORT_SOURCE_FD, fd);
                 ski.registeredEvents(0);
             }
         } else {
             assert ski.registeredEvents() == 0;
         }
     }

     @Override
     public void setEventOps(SelectionKeyImpl ski) {
         ensureOpen();
         synchronized (updateLock) {
             updateKeys.addLast(ski);
         }
     }

     @Override
     public Selector wakeup() {
         synchronized (interruptLock) {
             if (!interruptTriggered) {
                 try {
                     port_send(pfd, 0);
                 } catch (IOException ioe) {
                     throw new InternalError(ioe);
                 }
                 interruptTriggered = true;
             }
         }
         return this;
     }

     private void clearInterrupt() throws IOException {
         synchronized (interruptLock) {
             interruptTriggered = false;
         }
     }

     private short getSource(int i) {
         int offset = SIZEOF_PORT_EVENT * i + OFFSETOF_SOURCE;
         return pollArray.getShort(offset);
     }

     private int getEventOps(int i) {
         int offset = SIZEOF_PORT_EVENT * i + OFFSETOF_EVENTS;
         return pollArray.getInt(offset);
     }

     private int getDescriptor(int i) {
         //assert Unsafe.getUnsafe().addressSize() == 8;
         int offset = SIZEOF_PORT_EVENT * i + OFFSETOF_OBJECT;
         return (int) pollArray.getLong(offset);
     }
 }
	/*
	* Copyright (c) 2012, 2018, 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 sun.nio.ch;

	import java.io.IOException;
	import java.nio.channels.ClosedSelectorException;
	import java.nio.channels.SelectionKey;
	import java.nio.channels.Selector;
	import java.nio.channels.spi.SelectorProvider;
	import java.util.ArrayDeque;
	import java.util.Deque;
	import java.util.HashMap;
	import java.util.Map;
	import java.util.concurrent.TimeUnit;
	import java.util.function.Consumer;

	import static sun.nio.ch.SolarisEventPort.PORT_SOURCE_FD;
	import static sun.nio.ch.SolarisEventPort.PORT_SOURCE_USER;
	import static sun.nio.ch.SolarisEventPort.SIZEOF_PORT_EVENT;
	import static sun.nio.ch.SolarisEventPort.OFFSETOF_EVENTS;
	import static sun.nio.ch.SolarisEventPort.OFFSETOF_SOURCE;
	import static sun.nio.ch.SolarisEventPort.OFFSETOF_OBJECT;
	import static sun.nio.ch.SolarisEventPort.port_create;
	import static sun.nio.ch.SolarisEventPort.port_close;
	import static sun.nio.ch.SolarisEventPort.port_associate;
	import static sun.nio.ch.SolarisEventPort.port_dissociate;
	import static sun.nio.ch.SolarisEventPort.port_getn;
	import static sun.nio.ch.SolarisEventPort.port_send;

	/**
	* Selector implementation based on the Solaris event port mechanism.
	*/

	class EventPortSelectorImpl
	extends SelectorImpl
	{
	// maximum number of events to retrive in one call to port_getn
	static final int MAX_EVENTS = Math.min(IOUtil.fdLimit()-1, 1024);

	// port file descriptor
	private final int pfd;

	// the poll array (populated by port_getn)
	private final long pollArrayAddress;
	private final AllocatedNativeObject pollArray;

	// maps file descriptor to selection key, synchronize on selector
	private final Map<Integer, SelectionKeyImpl> fdToKey = new HashMap<>();

	// the last update operation, incremented by processUpdateQueue
	private int lastUpdate;

	// pending new registrations/updates, queued by setEventOps and
	// updateSelectedKeys
	private final Object updateLock = new Object();
	private final Deque<SelectionKeyImpl> updateKeys = new ArrayDeque<>();

	// interrupt triggering and clearing
	private final Object interruptLock = new Object();
	private boolean interruptTriggered;

	EventPortSelectorImpl(SelectorProvider sp) throws IOException {
	super(sp);

	this.pfd = port_create();

	int allocationSize = MAX_EVENTS * SIZEOF_PORT_EVENT;
	this.pollArray = new AllocatedNativeObject(allocationSize, false);
	this.pollArrayAddress = pollArray.address();
	}

	private void ensureOpen() {
	if (!isOpen())
	throw new ClosedSelectorException();
	}

	@Override
	protected int doSelect(Consumer<SelectionKey> action, long timeout)
	throws IOException
	{
	assert Thread.holdsLock(this);

	long to = timeout;
	boolean blocking = (to != 0);
	boolean timedPoll = (to > 0);

	int numEvents;
	processUpdateQueue();
	processDeregisterQueue();
	try {
	begin(blocking);

	do {
	long startTime = timedPoll ? System.nanoTime() : 0;
	numEvents = port_getn(pfd, pollArrayAddress, MAX_EVENTS, to);
	if (numEvents == IOStatus.INTERRUPTED && timedPoll) {
	// timed poll interrupted so need to adjust timeout
	long adjust = System.nanoTime() - startTime;
	to -= TimeUnit.MILLISECONDS.convert(adjust, TimeUnit.NANOSECONDS);
	if (to <= 0) {
	// timeout also expired so no retry
	numEvents = 0;
	}
	}
	} while (numEvents == IOStatus.INTERRUPTED);
	assert IOStatus.check(numEvents);

	} finally {
	end(blocking);
	}
	processDeregisterQueue();
	return processPortEvents(numEvents, action);
	}

	/**
	* Process new registrations and changes to the interest ops.
	*/
	private void processUpdateQueue() throws IOException {
	assert Thread.holdsLock(this);

	// bump lastUpdate to ensure that the interest ops are changed at most
	// once per bulk update
	lastUpdate++;

	synchronized (updateLock) {
	SelectionKeyImpl ski;
	while ((ski = updateKeys.pollFirst()) != null) {
	if (ski.isValid()) {
	int fd = ski.getFDVal();
	// add to fdToKey if needed
	SelectionKeyImpl previous = fdToKey.putIfAbsent(fd, ski);
	assert (previous == null) \|\| (previous == ski);

	int newEvents = ski.translateInterestOps();
	if (newEvents != ski.registeredEvents()) {
	if (newEvents == 0) {
	port_dissociate(pfd, PORT_SOURCE_FD, fd);
	} else {
	port_associate(pfd, PORT_SOURCE_FD, fd, newEvents);
	}
	ski.registeredEvents(newEvents);
	}
	}
	}
	}
	}

	/**
	* Process the polled events and re-queue the selected keys so the file
	* descriptors are re-associated at the next select operation.
	*/
	private int processPortEvents(int numEvents, Consumer<SelectionKey> action)
	throws IOException
	{
	assert Thread.holdsLock(this);

	int numKeysUpdated = 0;
	boolean interrupted = false;

	// Process the polled events while holding the update lock. This allows
	// keys to be queued for ready file descriptors so they can be
	// re-associated at the next select. The selected-key can be updated
	// in this pass.
	synchronized (updateLock) {
	for (int i = 0; i < numEvents; i++) {
	short source = getSource(i);
	if (source == PORT_SOURCE_FD) {
	int fd = getDescriptor(i);
	SelectionKeyImpl ski = fdToKey.get(fd);
	if (ski != null) {
	ski.registeredEvents(0);
	updateKeys.addLast(ski);

	// update selected-key set if no action specified
	if (action == null) {
	int rOps = getEventOps(i);
	numKeysUpdated += processReadyEvents(rOps, ski, null);
	}

	}
	} else if (source == PORT_SOURCE_USER) {
	interrupted = true;
	} else {
	assert false;
	}
	}
	}

	// if an action specified then iterate over the polled events again so
	// that the action is performed without holding the update lock.
	if (action != null) {
	for (int i = 0; i < numEvents; i++) {
	short source = getSource(i);
	if (source == PORT_SOURCE_FD) {
	int fd = getDescriptor(i);
	SelectionKeyImpl ski = fdToKey.get(fd);
	if (ski != null) {
	int rOps = getEventOps(i);
	numKeysUpdated += processReadyEvents(rOps, ski, action);
	}
	}
	}
	}

	if (interrupted) {
	clearInterrupt();
	}
	return numKeysUpdated;
	}

	@Override
	protected void implClose() throws IOException {
	assert !isOpen();
	assert Thread.holdsLock(this);

	// prevent further wakeup
	synchronized (interruptLock) {
	interruptTriggered = true;
	}

	port_close(pfd);
	pollArray.free();
	}

	@Override
	protected void implDereg(SelectionKeyImpl ski) throws IOException {
	assert !ski.isValid();
	assert Thread.holdsLock(this);

	int fd = ski.getFDVal();
	if (fdToKey.remove(fd) != null) {
	if (ski.registeredEvents() != 0) {
	port_dissociate(pfd, PORT_SOURCE_FD, fd);
	ski.registeredEvents(0);
	}
	} else {
	assert ski.registeredEvents() == 0;
	}
	}

	@Override
	public void setEventOps(SelectionKeyImpl ski) {
	ensureOpen();
	synchronized (updateLock) {
	updateKeys.addLast(ski);
	}
	}

	@Override
	public Selector wakeup() {
	synchronized (interruptLock) {
	if (!interruptTriggered) {
	try {
	port_send(pfd, 0);
	} catch (IOException ioe) {
	throw new InternalError(ioe);
	}
	interruptTriggered = true;
	}
	}
	return this;
	}

	private void clearInterrupt() throws IOException {
	synchronized (interruptLock) {
	interruptTriggered = false;
	}
	}

	private short getSource(int i) {
	int offset = SIZEOF_PORT_EVENT * i + OFFSETOF_SOURCE;
	return pollArray.getShort(offset);
	}

	private int getEventOps(int i) {
	int offset = SIZEOF_PORT_EVENT * i + OFFSETOF_EVENTS;
	return pollArray.getInt(offset);
	}

	private int getDescriptor(int i) {
	//assert Unsafe.getUnsafe().addressSize() == 8;
	int offset = SIZEOF_PORT_EVENT * i + OFFSETOF_OBJECT;
	return (int) pollArray.getLong(offset);
	}
	}