BlockGuardOs.java revision 78c7cc547101002b9f9043cf3845970719d1bda8 
1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package libcore.io;
18
19import dalvik.system.BlockGuard;
20import java.io.FileDescriptor;
21import java.nio.ByteBuffer;
22import static libcore.io.OsConstants.*;
23
24/**
25 * Informs BlockGuard of any activity it should be aware of.
26 */
27public class BlockGuardOs extends ForwardingOs {
28    public BlockGuardOs(Os os) {
29        super(os);
30    }
31
32    public void fdatasync(FileDescriptor fd) throws ErrnoException {
33        BlockGuard.getThreadPolicy().onWriteToDisk();
34        os.fdatasync(fd);
35    }
36
37    public void fsync(FileDescriptor fd) throws ErrnoException {
38        BlockGuard.getThreadPolicy().onWriteToDisk();
39        os.fsync(fd);
40    }
41
42    public void ftruncate(FileDescriptor fd, long length) throws ErrnoException {
43        BlockGuard.getThreadPolicy().onWriteToDisk();
44        os.ftruncate(fd, length);
45    }
46
47    public FileDescriptor open(String path, int flags, int mode) throws ErrnoException {
48        BlockGuard.getThreadPolicy().onReadFromDisk();
49        if ((mode & O_ACCMODE) != O_RDONLY) {
50            BlockGuard.getThreadPolicy().onWriteToDisk();
51        }
52        return os.open(path, flags, mode);
53    }
54
55    public int read(FileDescriptor fd, ByteBuffer buffer) throws ErrnoException {
56        BlockGuard.getThreadPolicy().onReadFromDisk();
57        return os.read(fd, buffer);
58    }
59
60    public int read(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount) throws ErrnoException {
61        BlockGuard.getThreadPolicy().onReadFromDisk();
62        return os.read(fd, bytes, byteOffset, byteCount);
63    }
64
65    public int write(FileDescriptor fd, ByteBuffer buffer) throws ErrnoException {
66        BlockGuard.getThreadPolicy().onWriteToDisk();
67        return os.write(fd, buffer);
68    }
69
70    public int write(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount) throws ErrnoException {
71        BlockGuard.getThreadPolicy().onWriteToDisk();
72        return os.write(fd, bytes, byteOffset, byteCount);
73    }
74}
75