1 /* 2 * Copyright (c) 2017, 2023, 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 package sun.nio.ch; 26 27 import java.io.IOException; 28 import static sun.nio.ch.KQueue.*; 29 30 /** 31 * Poller implementation based on the kqueue facility. 32 */ 33 class KQueuePoller extends Poller { 34 private final int kqfd; 35 private final int filter; 36 private final int maxEvents; 37 private final long address; 38 39 KQueuePoller(boolean subPoller, boolean read) throws IOException { 40 this.kqfd = KQueue.create(); 41 this.filter = (read) ? EVFILT_READ : EVFILT_WRITE; 42 this.maxEvents = (subPoller) ? 64 : 512; 43 this.address = KQueue.allocatePollArray(maxEvents); 44 } 45 46 @Override 47 int fdVal() { 48 return kqfd; 49 } 50 51 @Override 52 void implRegister(int fdVal) throws IOException { 53 int err = KQueue.register(kqfd, fdVal, filter, (EV_ADD|EV_ONESHOT)); 54 if (err != 0) 55 throw new IOException("kevent failed: " + err); 56 } 57 58 @Override 59 void implDeregister(int fdVal, boolean polled) { 60 // event was deleted if already polled 61 if (!polled) { 62 KQueue.register(kqfd, fdVal, filter, EV_DELETE); 63 } 64 } 65 66 @Override 67 int poll(int timeout) throws IOException { 68 int n = KQueue.poll(kqfd, address, maxEvents, timeout); 69 int i = 0; 70 while (i < n) { 71 long keventAddress = KQueue.getEvent(address, i); 72 int fdVal = KQueue.getDescriptor(keventAddress); 73 polled(fdVal); 74 i++; 75 } 76 return n; 77 } 78 }