1 /*
   2  * Copyright (c) 2001, 2015, 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         try {
  61             pollWrapper = new PollArrayWrapper(INIT_CAP);
  62             pollWrapper.initInterrupt(fd0, fd1);
  63             channelArray = new SelectionKeyImpl[INIT_CAP];
  64         } catch (Throwable t) {
  65             try {
  66                 FileDispatcherImpl.closeIntFD(fd0);
  67             } catch (IOException ioe0) {
  68                 t.addSuppressed(ioe0);
  69             }
  70             try {
  71                 FileDispatcherImpl.closeIntFD(fd1);
  72             } catch (IOException ioe1) {
  73                 t.addSuppressed(ioe1);
  74             }
  75             throw t;
  76         }
  77     }
  78 
  79     protected int doSelect(long timeout)
  80         throws IOException
  81     {
  82         if (channelArray == null)
  83             throw new ClosedSelectorException();
  84         processDeregisterQueue();
  85         try {
  86             begin();
  87             pollWrapper.poll(totalChannels, 0, timeout);
  88         } finally {
  89             end();
  90         }
  91         processDeregisterQueue();
  92         int numKeysUpdated = updateSelectedKeys();
  93         if (pollWrapper.getReventOps(0) != 0) {
  94             // Clear the wakeup pipe
  95             pollWrapper.putReventOps(0, 0);
  96             synchronized (interruptLock) {
  97                 IOUtil.drain(fd0);
  98                 interruptTriggered = false;
  99             }
 100         }
 101         return numKeysUpdated;
 102     }
 103 
 104     protected void implCloseInterrupt() throws IOException {
 105         // prevent further wakeup
 106         synchronized (interruptLock) {
 107             interruptTriggered = true;
 108         }
 109         FileDispatcherImpl.closeIntFD(fd0);
 110         FileDispatcherImpl.closeIntFD(fd1);
 111         fd0 = -1;
 112         fd1 = -1;
 113         pollWrapper.release(0);
 114     }
 115 
 116     public Selector wakeup() {
 117         synchronized (interruptLock) {
 118             if (!interruptTriggered) {
 119                 pollWrapper.interrupt();
 120                 interruptTriggered = true;
 121             }
 122         }
 123         return this;
 124     }
 125 
 126 }