1 /*
   2  * Copyright (c) 2001, 2016, 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 
  33 
  34 /**
  35  * An implementation of Selector for Solaris.
  36  */
  37 
  38 class PollSelectorImpl
  39     extends AbstractPollSelectorImpl
  40 {
  41 
  42     // File descriptors used for interrupt
  43     private int fd0;
  44     private int fd1;
  45 
  46     // Lock for interrupt triggering and clearing
  47     private Object interruptLock = new Object();
  48     private boolean interruptTriggered = false;
  49 
  50     /**
  51      * Package private constructor called by factory method in
  52      * the abstract superclass Selector.
  53      */
  54     PollSelectorImpl(SelectorProvider sp) {
  55         super(sp, 1, 1);
  56         long pipeFds = IOUtil.makePipe(false);
  57         fd0 = (int) (pipeFds >>> 32);
  58         fd1 = (int) pipeFds;
  59         try {
  60             pollWrapper = new PollArrayWrapper(INIT_CAP);
  61             pollWrapper.initInterrupt(fd0, fd1);
  62             channelArray = new SelectionKeyImpl[INIT_CAP];
  63         } catch (Throwable t) {
  64             try {
  65                 FileDispatcherImpl.closeIntFD(fd0);
  66             } catch (IOException ioe0) {
  67                 t.addSuppressed(ioe0);
  68             }
  69             try {
  70                 FileDispatcherImpl.closeIntFD(fd1);
  71             } catch (IOException ioe1) {
  72                 t.addSuppressed(ioe1);
  73             }
  74             throw t;
  75         }
  76     }
  77 
  78     protected int doSelect(long timeout)
  79         throws IOException
  80     {
  81         if (channelArray == null)
  82             throw new ClosedSelectorException();
  83         processDeregisterQueue();
  84         try {
  85             begin();
  86             pollWrapper.poll(totalChannels, 0, timeout);
  87         } finally {
  88             end();
  89         }
  90         processDeregisterQueue();
  91         int numKeysUpdated = updateSelectedKeys();
  92         if (pollWrapper.getReventOps(0) != 0) {
  93             // Clear the wakeup pipe
  94             pollWrapper.putReventOps(0, 0);
  95             synchronized (interruptLock) {
  96                 IOUtil.drain(fd0);
  97                 interruptTriggered = false;
  98             }
  99         }
 100         return numKeysUpdated;
 101     }
 102 
 103     protected void implCloseInterrupt() throws IOException {
 104         // prevent further wakeup
 105         synchronized (interruptLock) {
 106             interruptTriggered = true;
 107         }
 108         FileDispatcherImpl.closeIntFD(fd0);
 109         FileDispatcherImpl.closeIntFD(fd1);
 110         fd0 = -1;
 111         fd1 = -1;
 112         pollWrapper.release(0);
 113     }
 114 
 115     public Selector wakeup() {
 116         synchronized (interruptLock) {
 117             if (!interruptTriggered) {
 118                 pollWrapper.interrupt();
 119                 interruptTriggered = true;
 120             }
 121         }
 122         return this;
 123     }
 124 
 125 }