1 /*
   2  * Copyright (c) 2001, 2009, 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 sun.nio.ch;
  27 
  28 import java.io.IOException;
  29 import java.nio.channels.*;
  30 import java.nio.channels.spi.*;
  31 import java.util.*;
  32 import sun.misc.*;
  33 
  34 
  35 /**
  36  * An implementation of Selector for Solaris.
  37  */
  38 
  39 class PollSelectorImpl
  40     extends AbstractPollSelectorImpl
  41 {
  42 
  43     // File descriptors used for interrupt
  44     private int fd0;
  45     private int fd1;
  46 
  47     // Lock for interrupt triggering and clearing
  48     private Object interruptLock = new Object();
  49     private boolean interruptTriggered = false;
  50 
  51     /**
  52      * Package private constructor called by factory method in
  53      * the abstract superclass Selector.
  54      */
  55     PollSelectorImpl(SelectorProvider sp) {
  56         super(sp, 1, 1);
  57         long pipeFds = IOUtil.makePipe(false);
  58         fd0 = (int) (pipeFds >>> 32);
  59         fd1 = (int) pipeFds;
  60         pollWrapper = new PollArrayWrapper(INIT_CAP);
  61         pollWrapper.initInterrupt(fd0, fd1);
  62         channelArray = new SelectionKeyImpl[INIT_CAP];
  63     }
  64 
  65     protected int doSelect(long timeout)
  66         throws IOException
  67     {
  68         if (channelArray == null)
  69             throw new ClosedSelectorException();
  70         processDeregisterQueue();
  71         try {
  72             begin();
  73             pollWrapper.poll(totalChannels, 0, timeout);
  74         } finally {
  75             end();
  76         }
  77         processDeregisterQueue();
  78         int numKeysUpdated = updateSelectedKeys();
  79         if (pollWrapper.getReventOps(0) != 0) {
  80             // Clear the wakeup pipe
  81             pollWrapper.putReventOps(0, 0);
  82             synchronized (interruptLock) {
  83                 IOUtil.drain(fd0);
  84                 interruptTriggered = false;
  85             }
  86         }
  87         return numKeysUpdated;
  88     }
  89 
  90     protected void implCloseInterrupt() throws IOException {
  91         // prevent further wakeup
  92         synchronized (interruptLock) {
  93             interruptTriggered = true;
  94         }
  95         FileDispatcherImpl.closeIntFD(fd0);
  96         FileDispatcherImpl.closeIntFD(fd1);
  97         fd0 = -1;
  98         fd1 = -1;
  99         pollWrapper.release(0);
 100     }
 101 
 102     public Selector wakeup() {
 103         synchronized (interruptLock) {
 104             if (!interruptTriggered) {
 105                 pollWrapper.interrupt();
 106                 interruptTriggered = true;
 107             }
 108         }
 109         return this;
 110     }
 111 
 112 }