1/*
2 * Copyright (c) 2001, 2012, 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
26package sun.nio.ch;
27
28
29/**
30 * Manipulates a native array of pollfd structs.
31 *
32 * @author Mike McCloskey
33 * @since 1.4
34 */
35
36public abstract class AbstractPollArrayWrapper {
37
38    // Miscellaneous constants
39    static final short SIZE_POLLFD   = 8;
40    static final short FD_OFFSET     = 0;
41    static final short EVENT_OFFSET  = 4;
42    static final short REVENT_OFFSET = 6;
43
44    // The poll fd array
45    protected AllocatedNativeObject pollArray;
46
47    // Number of valid entries in the pollArray
48    protected int totalChannels = 0;
49
50    // Base address of the native pollArray
51    protected long pollArrayAddress;
52
53    // Access methods for fd structures
54    int getEventOps(int i) {
55        int offset = SIZE_POLLFD * i + EVENT_OFFSET;
56        return pollArray.getShort(offset);
57    }
58
59    int getReventOps(int i) {
60        int offset = SIZE_POLLFD * i + REVENT_OFFSET;
61        return pollArray.getShort(offset);
62    }
63
64    int getDescriptor(int i) {
65        int offset = SIZE_POLLFD * i + FD_OFFSET;
66        return pollArray.getInt(offset);
67    }
68
69    void putEventOps(int i, int event) {
70        int offset = SIZE_POLLFD * i + EVENT_OFFSET;
71        pollArray.putShort(offset, (short)event);
72    }
73
74    void putReventOps(int i, int revent) {
75        int offset = SIZE_POLLFD * i + REVENT_OFFSET;
76        pollArray.putShort(offset, (short)revent);
77    }
78
79    void putDescriptor(int i, int fd) {
80        int offset = SIZE_POLLFD * i + FD_OFFSET;
81        pollArray.putInt(offset, fd);
82    }
83
84}
85