1105 lines
37 KiB
Java
1105 lines
37 KiB
Java
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/*
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* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation. Oracle designates this
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* particular file as subject to the "Classpath" exception as provided
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* by Oracle in the LICENSE file that accompanied this code.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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package sun.nio.ch;
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import cli.Microsoft.Win32.SafeHandles.SafeFileHandle;
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import cli.System.IntPtr;
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import cli.System.IO.FileStream;
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import cli.System.Runtime.InteropServices.DllImportAttribute;
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import java.io.FileDescriptor;
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import java.io.IOException;
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import java.nio.ByteBuffer;
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import java.nio.MappedByteBuffer;
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import java.nio.channels.*;
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import java.util.ArrayList;
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import java.util.List;
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import java.security.AccessController;
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import sun.misc.Cleaner;
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import sun.misc.IoTrace;
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import sun.security.action.GetPropertyAction;
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public class FileChannelImpl
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extends FileChannel
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{
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private static final boolean win32 = ikvm.internal.Util.WINDOWS;
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// Memory allocation size for mapping buffers
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private static final long allocationGranularity = 64 * 1024; // HACK we're using a hard coded value here that works on all mainstream platforms
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// Used to make native read and write calls
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private final FileDispatcher nd;
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// File descriptor
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private final FileDescriptor fd;
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// File access mode (immutable)
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private final boolean writable;
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private final boolean readable;
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private final boolean append;
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// Required to prevent finalization of creating stream (immutable)
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private final Object parent;
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// The path of the referenced file (null if the parent stream is created with a file descriptor)
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private final String path;
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// Thread-safe set of IDs of native threads, for signalling
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private final NativeThreadSet threads = new NativeThreadSet(2);
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// Lock for operations involving position and size
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private final Object positionLock = new Object();
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private FileChannelImpl(FileDescriptor fd, String path, boolean readable,
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boolean writable, boolean append, Object parent)
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{
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this.fd = fd;
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this.readable = readable;
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this.writable = writable;
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this.append = append;
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this.parent = parent;
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this.path = path;
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this.nd = new FileDispatcherImpl(append);
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}
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// Used by FileInputStream.getChannel() and RandomAccessFile.getChannel()
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public static FileChannel open(FileDescriptor fd, String path,
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boolean readable, boolean writable,
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Object parent)
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{
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return new FileChannelImpl(fd, path, readable, writable, false, parent);
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}
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// Used by FileOutputStream.getChannel
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public static FileChannel open(FileDescriptor fd, String path,
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boolean readable, boolean writable,
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boolean append, Object parent)
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{
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return new FileChannelImpl(fd, path, readable, writable, append, parent);
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}
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private void ensureOpen() throws IOException {
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if (!isOpen())
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throw new ClosedChannelException();
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}
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// -- Standard channel operations --
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protected void implCloseChannel() throws IOException {
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// Release and invalidate any locks that we still hold
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if (fileLockTable != null) {
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for (FileLock fl: fileLockTable.removeAll()) {
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synchronized (fl) {
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if (fl.isValid()) {
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nd.release(fd, fl.position(), fl.size());
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((FileLockImpl)fl).invalidate();
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}
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}
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}
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}
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nd.preClose(fd);
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threads.signalAndWait();
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if (parent != null) {
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// Close the fd via the parent stream's close method. The parent
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// will reinvoke our close method, which is defined in the
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// superclass AbstractInterruptibleChannel, but the isOpen logic in
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// that method will prevent this method from being reinvoked.
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//
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((java.io.Closeable)parent).close();
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} else {
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nd.close(fd);
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}
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}
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public int read(ByteBuffer dst) throws IOException {
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ensureOpen();
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if (!readable)
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throw new NonReadableChannelException();
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synchronized (positionLock) {
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int n = 0;
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int ti = -1;
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Object traceContext = IoTrace.fileReadBegin(path);
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try {
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begin();
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ti = threads.add();
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if (!isOpen())
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return 0;
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do {
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n = IOUtil.read(fd, dst, -1, nd, positionLock);
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} while ((n == IOStatus.INTERRUPTED) && isOpen());
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return IOStatus.normalize(n);
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} finally {
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threads.remove(ti);
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IoTrace.fileReadEnd(traceContext, n > 0 ? n : 0);
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end(n > 0);
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assert IOStatus.check(n);
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}
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}
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}
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public long read(ByteBuffer[] dsts, int offset, int length)
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throws IOException
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{
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if ((offset < 0) || (length < 0) || (offset > dsts.length - length))
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throw new IndexOutOfBoundsException();
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ensureOpen();
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if (!readable)
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throw new NonReadableChannelException();
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synchronized (positionLock) {
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long n = 0;
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int ti = -1;
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Object traceContext = IoTrace.fileReadBegin(path);
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try {
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begin();
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ti = threads.add();
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if (!isOpen())
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return 0;
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do {
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n = IOUtil.read(fd, dsts, offset, length, nd);
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} while ((n == IOStatus.INTERRUPTED) && isOpen());
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return IOStatus.normalize(n);
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} finally {
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threads.remove(ti);
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IoTrace.fileReadEnd(traceContext, n > 0 ? n : 0);
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end(n > 0);
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assert IOStatus.check(n);
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}
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}
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}
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public int write(ByteBuffer src) throws IOException {
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ensureOpen();
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if (!writable)
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throw new NonWritableChannelException();
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synchronized (positionLock) {
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int n = 0;
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int ti = -1;
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Object traceContext = IoTrace.fileWriteBegin(path);
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try {
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begin();
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ti = threads.add();
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if (!isOpen())
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return 0;
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do {
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n = IOUtil.write(fd, src, -1, nd, positionLock);
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} while ((n == IOStatus.INTERRUPTED) && isOpen());
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return IOStatus.normalize(n);
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} finally {
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threads.remove(ti);
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end(n > 0);
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IoTrace.fileWriteEnd(traceContext, n > 0 ? n : 0);
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assert IOStatus.check(n);
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}
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}
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}
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public long write(ByteBuffer[] srcs, int offset, int length)
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throws IOException
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{
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if ((offset < 0) || (length < 0) || (offset > srcs.length - length))
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throw new IndexOutOfBoundsException();
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ensureOpen();
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if (!writable)
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throw new NonWritableChannelException();
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synchronized (positionLock) {
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long n = 0;
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int ti = -1;
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Object traceContext = IoTrace.fileWriteBegin(path);
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try {
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begin();
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ti = threads.add();
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if (!isOpen())
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return 0;
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do {
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n = IOUtil.write(fd, srcs, offset, length, nd);
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} while ((n == IOStatus.INTERRUPTED) && isOpen());
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return IOStatus.normalize(n);
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} finally {
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threads.remove(ti);
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IoTrace.fileWriteEnd(traceContext, n > 0 ? n : 0);
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end(n > 0);
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assert IOStatus.check(n);
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}
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}
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}
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// -- Other operations --
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public long position() throws IOException {
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ensureOpen();
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synchronized (positionLock) {
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long p = -1;
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int ti = -1;
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try {
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begin();
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ti = threads.add();
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if (!isOpen())
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return 0;
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do {
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// in append-mode then position is advanced to end before writing
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p = (append) ? nd.size(fd) : position0(fd, -1);
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} while ((p == IOStatus.INTERRUPTED) && isOpen());
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return IOStatus.normalize(p);
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} finally {
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threads.remove(ti);
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end(p > -1);
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assert IOStatus.check(p);
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}
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}
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}
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public FileChannel position(long newPosition) throws IOException {
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ensureOpen();
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if (newPosition < 0)
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throw new IllegalArgumentException();
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synchronized (positionLock) {
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long p = -1;
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int ti = -1;
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try {
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begin();
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ti = threads.add();
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if (!isOpen())
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return null;
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do {
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p = position0(fd, newPosition);
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} while ((p == IOStatus.INTERRUPTED) && isOpen());
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return this;
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} finally {
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threads.remove(ti);
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end(p > -1);
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assert IOStatus.check(p);
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}
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}
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}
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|
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public long size() throws IOException {
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ensureOpen();
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synchronized (positionLock) {
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long s = -1;
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int ti = -1;
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try {
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begin();
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ti = threads.add();
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if (!isOpen())
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return -1;
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do {
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s = nd.size(fd);
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} while ((s == IOStatus.INTERRUPTED) && isOpen());
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return IOStatus.normalize(s);
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|
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} finally {
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|
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threads.remove(ti);
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end(s > -1);
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|
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assert IOStatus.check(s);
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}
|
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|
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}
|
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|
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}
|
||
|
|
|
||
|
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public FileChannel truncate(long size) throws IOException {
|
||
|
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ensureOpen();
|
||
|
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if (size < 0)
|
||
|
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throw new IllegalArgumentException();
|
||
|
|
if (size > size())
|
||
|
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return this;
|
||
|
|
if (!writable)
|
||
|
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throw new NonWritableChannelException();
|
||
|
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synchronized (positionLock) {
|
||
|
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int rv = -1;
|
||
|
|
long p = -1;
|
||
|
|
int ti = -1;
|
||
|
|
try {
|
||
|
|
begin();
|
||
|
|
ti = threads.add();
|
||
|
|
if (!isOpen())
|
||
|
|
return null;
|
||
|
|
|
||
|
|
// get current position
|
||
|
|
do {
|
||
|
|
p = position0(fd, -1);
|
||
|
|
} while ((p == IOStatus.INTERRUPTED) && isOpen());
|
||
|
|
if (!isOpen())
|
||
|
|
return null;
|
||
|
|
assert p >= 0;
|
||
|
|
|
||
|
|
// truncate file
|
||
|
|
do {
|
||
|
|
rv = nd.truncate(fd, size);
|
||
|
|
} while ((rv == IOStatus.INTERRUPTED) && isOpen());
|
||
|
|
if (!isOpen())
|
||
|
|
return null;
|
||
|
|
|
||
|
|
// [IKVM] in append mode we're not allowed to seek backwards, but the atomic append will honor the new file size
|
||
|
|
if (append)
|
||
|
|
return this;
|
||
|
|
|
||
|
|
// set position to size if greater than size
|
||
|
|
if (p > size)
|
||
|
|
p = size;
|
||
|
|
do {
|
||
|
|
rv = (int)position0(fd, p);
|
||
|
|
} while ((rv == IOStatus.INTERRUPTED) && isOpen());
|
||
|
|
return this;
|
||
|
|
} finally {
|
||
|
|
threads.remove(ti);
|
||
|
|
end(rv > -1);
|
||
|
|
assert IOStatus.check(rv);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
public void force(boolean metaData) throws IOException {
|
||
|
|
ensureOpen();
|
||
|
|
int rv = -1;
|
||
|
|
int ti = -1;
|
||
|
|
try {
|
||
|
|
begin();
|
||
|
|
ti = threads.add();
|
||
|
|
if (!isOpen())
|
||
|
|
return;
|
||
|
|
do {
|
||
|
|
rv = nd.force(fd, metaData);
|
||
|
|
} while ((rv == IOStatus.INTERRUPTED) && isOpen());
|
||
|
|
} finally {
|
||
|
|
threads.remove(ti);
|
||
|
|
end(rv > -1);
|
||
|
|
assert IOStatus.check(rv);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
private long transferToArbitraryChannel(long position, int icount,
|
||
|
|
WritableByteChannel target)
|
||
|
|
throws IOException
|
||
|
|
{
|
||
|
|
// Untrusted target: Use a newly-erased buffer
|
||
|
|
int c = Math.min(icount, TRANSFER_SIZE);
|
||
|
|
ByteBuffer bb = ByteBuffer.allocate(c);
|
||
|
|
long tw = 0; // Total bytes written
|
||
|
|
long pos = position;
|
||
|
|
try {
|
||
|
|
while (tw < icount) {
|
||
|
|
bb.limit(Math.min((int)(icount - tw), TRANSFER_SIZE));
|
||
|
|
int nr = read(bb, pos);
|
||
|
|
if (nr <= 0)
|
||
|
|
break;
|
||
|
|
bb.flip();
|
||
|
|
// ## Bug: Will block writing target if this channel
|
||
|
|
// ## is asynchronously closed
|
||
|
|
int nw = target.write(bb);
|
||
|
|
tw += nw;
|
||
|
|
if (nw != nr)
|
||
|
|
break;
|
||
|
|
pos += nw;
|
||
|
|
bb.clear();
|
||
|
|
}
|
||
|
|
return tw;
|
||
|
|
} catch (IOException x) {
|
||
|
|
if (tw > 0)
|
||
|
|
return tw;
|
||
|
|
throw x;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
public long transferTo(long position, long count,
|
||
|
|
WritableByteChannel target)
|
||
|
|
throws IOException
|
||
|
|
{
|
||
|
|
ensureOpen();
|
||
|
|
if (!target.isOpen())
|
||
|
|
throw new ClosedChannelException();
|
||
|
|
if (!readable)
|
||
|
|
throw new NonReadableChannelException();
|
||
|
|
if (target instanceof FileChannelImpl &&
|
||
|
|
!((FileChannelImpl)target).writable)
|
||
|
|
throw new NonWritableChannelException();
|
||
|
|
if ((position < 0) || (count < 0))
|
||
|
|
throw new IllegalArgumentException();
|
||
|
|
long sz = size();
|
||
|
|
if (position > sz)
|
||
|
|
return 0;
|
||
|
|
int icount = (int)Math.min(count, Integer.MAX_VALUE);
|
||
|
|
if ((sz - position) < icount)
|
||
|
|
icount = (int)(sz - position);
|
||
|
|
|
||
|
|
// Slow path for untrusted targets
|
||
|
|
return transferToArbitraryChannel(position, icount, target);
|
||
|
|
}
|
||
|
|
|
||
|
|
private long transferFromFileChannel(FileChannelImpl src,
|
||
|
|
long position, long count)
|
||
|
|
throws IOException
|
||
|
|
{
|
||
|
|
if (!src.readable)
|
||
|
|
throw new NonReadableChannelException();
|
||
|
|
return transferFromArbitraryChannel(src, position, count);
|
||
|
|
}
|
||
|
|
|
||
|
|
private static final int TRANSFER_SIZE = 8192;
|
||
|
|
|
||
|
|
private long transferFromArbitraryChannel(ReadableByteChannel src,
|
||
|
|
long position, long count)
|
||
|
|
throws IOException
|
||
|
|
{
|
||
|
|
// Untrusted target: Use a newly-erased buffer
|
||
|
|
int c = (int)Math.min(count, TRANSFER_SIZE);
|
||
|
|
ByteBuffer bb = ByteBuffer.allocate(c);
|
||
|
|
long tw = 0; // Total bytes written
|
||
|
|
long pos = position;
|
||
|
|
try {
|
||
|
|
while (tw < count) {
|
||
|
|
bb.limit((int)Math.min((count - tw), (long)TRANSFER_SIZE));
|
||
|
|
// ## Bug: Will block reading src if this channel
|
||
|
|
// ## is asynchronously closed
|
||
|
|
int nr = src.read(bb);
|
||
|
|
if (nr <= 0)
|
||
|
|
break;
|
||
|
|
bb.flip();
|
||
|
|
int nw = write(bb, pos);
|
||
|
|
tw += nw;
|
||
|
|
if (nw != nr)
|
||
|
|
break;
|
||
|
|
pos += nw;
|
||
|
|
bb.clear();
|
||
|
|
}
|
||
|
|
return tw;
|
||
|
|
} catch (IOException x) {
|
||
|
|
if (tw > 0)
|
||
|
|
return tw;
|
||
|
|
throw x;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
public long transferFrom(ReadableByteChannel src,
|
||
|
|
long position, long count)
|
||
|
|
throws IOException
|
||
|
|
{
|
||
|
|
ensureOpen();
|
||
|
|
if (!src.isOpen())
|
||
|
|
throw new ClosedChannelException();
|
||
|
|
if (!writable)
|
||
|
|
throw new NonWritableChannelException();
|
||
|
|
if ((position < 0) || (count < 0))
|
||
|
|
throw new IllegalArgumentException();
|
||
|
|
if (position > size())
|
||
|
|
return 0;
|
||
|
|
if (src instanceof FileChannelImpl)
|
||
|
|
return transferFromFileChannel((FileChannelImpl)src,
|
||
|
|
position, count);
|
||
|
|
|
||
|
|
return transferFromArbitraryChannel(src, position, count);
|
||
|
|
}
|
||
|
|
|
||
|
|
public int read(ByteBuffer dst, long position) throws IOException {
|
||
|
|
if (dst == null)
|
||
|
|
throw new NullPointerException();
|
||
|
|
if (position < 0)
|
||
|
|
throw new IllegalArgumentException("Negative position");
|
||
|
|
if (!readable)
|
||
|
|
throw new NonReadableChannelException();
|
||
|
|
ensureOpen();
|
||
|
|
int n = 0;
|
||
|
|
int ti = -1;
|
||
|
|
Object traceContext = IoTrace.fileReadBegin(path);
|
||
|
|
try {
|
||
|
|
begin();
|
||
|
|
ti = threads.add();
|
||
|
|
if (!isOpen())
|
||
|
|
return -1;
|
||
|
|
do {
|
||
|
|
n = IOUtil.read(fd, dst, position, nd, positionLock);
|
||
|
|
} while ((n == IOStatus.INTERRUPTED) && isOpen());
|
||
|
|
return IOStatus.normalize(n);
|
||
|
|
} finally {
|
||
|
|
threads.remove(ti);
|
||
|
|
IoTrace.fileReadEnd(traceContext, n > 0 ? n : 0);
|
||
|
|
end(n > 0);
|
||
|
|
assert IOStatus.check(n);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
public int write(ByteBuffer src, long position) throws IOException {
|
||
|
|
if (src == null)
|
||
|
|
throw new NullPointerException();
|
||
|
|
if (position < 0)
|
||
|
|
throw new IllegalArgumentException("Negative position");
|
||
|
|
if (!writable)
|
||
|
|
throw new NonWritableChannelException();
|
||
|
|
ensureOpen();
|
||
|
|
int n = 0;
|
||
|
|
int ti = -1;
|
||
|
|
Object traceContext = IoTrace.fileWriteBegin(path);
|
||
|
|
try {
|
||
|
|
begin();
|
||
|
|
ti = threads.add();
|
||
|
|
if (!isOpen())
|
||
|
|
return -1;
|
||
|
|
do {
|
||
|
|
n = IOUtil.write(fd, src, position, nd, positionLock);
|
||
|
|
} while ((n == IOStatus.INTERRUPTED) && isOpen());
|
||
|
|
return IOStatus.normalize(n);
|
||
|
|
} finally {
|
||
|
|
threads.remove(ti);
|
||
|
|
end(n > 0);
|
||
|
|
IoTrace.fileWriteEnd(traceContext, n > 0 ? n : 0);
|
||
|
|
assert IOStatus.check(n);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
// -- Memory-mapped buffers --
|
||
|
|
|
||
|
|
private static class Unmapper
|
||
|
|
implements Runnable
|
||
|
|
{
|
||
|
|
// may be required to close file
|
||
|
|
private static final NativeDispatcher nd = new FileDispatcherImpl();
|
||
|
|
|
||
|
|
// keep track of mapped buffer usage
|
||
|
|
static volatile int count;
|
||
|
|
static volatile long totalSize;
|
||
|
|
static volatile long totalCapacity;
|
||
|
|
|
||
|
|
private volatile long address;
|
||
|
|
private final long size;
|
||
|
|
private final int cap;
|
||
|
|
private final FileDescriptor fd;
|
||
|
|
|
||
|
|
private Unmapper(long address, long size, int cap,
|
||
|
|
FileDescriptor fd)
|
||
|
|
{
|
||
|
|
assert (address != 0);
|
||
|
|
this.address = address;
|
||
|
|
this.size = size;
|
||
|
|
this.cap = cap;
|
||
|
|
this.fd = fd;
|
||
|
|
|
||
|
|
synchronized (Unmapper.class) {
|
||
|
|
count++;
|
||
|
|
totalSize += size;
|
||
|
|
totalCapacity += cap;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
public void run() {
|
||
|
|
if (address == 0)
|
||
|
|
return;
|
||
|
|
unmap0(address, size);
|
||
|
|
address = 0;
|
||
|
|
|
||
|
|
// if this mapping has a valid file descriptor then we close it
|
||
|
|
if (fd.valid()) {
|
||
|
|
try {
|
||
|
|
nd.close(fd);
|
||
|
|
} catch (IOException ignore) {
|
||
|
|
// nothing we can do
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
synchronized (Unmapper.class) {
|
||
|
|
count--;
|
||
|
|
totalSize -= size;
|
||
|
|
totalCapacity -= cap;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
private static void unmap(MappedByteBuffer bb) {
|
||
|
|
Cleaner cl = ((DirectBuffer)bb).cleaner();
|
||
|
|
if (cl != null)
|
||
|
|
cl.clean();
|
||
|
|
}
|
||
|
|
|
||
|
|
private static final int MAP_RO = 0;
|
||
|
|
private static final int MAP_RW = 1;
|
||
|
|
private static final int MAP_PV = 2;
|
||
|
|
|
||
|
|
public MappedByteBuffer map(MapMode mode, long position, long size)
|
||
|
|
throws IOException
|
||
|
|
{
|
||
|
|
ensureOpen();
|
||
|
|
if (position < 0L)
|
||
|
|
throw new IllegalArgumentException("Negative position");
|
||
|
|
if (size < 0L)
|
||
|
|
throw new IllegalArgumentException("Negative size");
|
||
|
|
if (position + size < 0)
|
||
|
|
throw new IllegalArgumentException("Position + size overflow");
|
||
|
|
if (size > Integer.MAX_VALUE)
|
||
|
|
throw new IllegalArgumentException("Size exceeds Integer.MAX_VALUE");
|
||
|
|
int imode = -1;
|
||
|
|
if (mode == MapMode.READ_ONLY)
|
||
|
|
imode = MAP_RO;
|
||
|
|
else if (mode == MapMode.READ_WRITE)
|
||
|
|
imode = MAP_RW;
|
||
|
|
else if (mode == MapMode.PRIVATE)
|
||
|
|
imode = MAP_PV;
|
||
|
|
assert (imode >= 0);
|
||
|
|
if ((mode != MapMode.READ_ONLY) && !writable)
|
||
|
|
throw new NonWritableChannelException();
|
||
|
|
if (!readable)
|
||
|
|
throw new NonReadableChannelException();
|
||
|
|
|
||
|
|
long addr = -1;
|
||
|
|
int ti = -1;
|
||
|
|
try {
|
||
|
|
begin();
|
||
|
|
ti = threads.add();
|
||
|
|
if (!isOpen())
|
||
|
|
return null;
|
||
|
|
if (size() < position + size) { // Extend file size
|
||
|
|
if (!writable) {
|
||
|
|
throw new IOException("Channel not open for writing " +
|
||
|
|
"- cannot extend file to required size");
|
||
|
|
}
|
||
|
|
int rv;
|
||
|
|
do {
|
||
|
|
rv = nd.truncate(fd, position + size);
|
||
|
|
} while ((rv == IOStatus.INTERRUPTED) && isOpen());
|
||
|
|
}
|
||
|
|
if (size == 0) {
|
||
|
|
addr = 0;
|
||
|
|
// a valid file descriptor is not required
|
||
|
|
FileDescriptor dummy = new FileDescriptor();
|
||
|
|
if ((!writable) || (imode == MAP_RO))
|
||
|
|
return Util.newMappedByteBufferR(0, 0, dummy, null);
|
||
|
|
else
|
||
|
|
return Util.newMappedByteBuffer(0, 0, dummy, null);
|
||
|
|
}
|
||
|
|
|
||
|
|
int pagePosition = (int)(position % allocationGranularity);
|
||
|
|
long mapPosition = position - pagePosition;
|
||
|
|
long mapSize = size + pagePosition;
|
||
|
|
try {
|
||
|
|
// If no exception was thrown from map0, the address is valid
|
||
|
|
addr = map0(imode, mapPosition, mapSize);
|
||
|
|
} catch (OutOfMemoryError x) {
|
||
|
|
// An OutOfMemoryError may indicate that we've exhausted memory
|
||
|
|
// so force gc and re-attempt map
|
||
|
|
System.gc();
|
||
|
|
try {
|
||
|
|
Thread.sleep(100);
|
||
|
|
} catch (InterruptedException y) {
|
||
|
|
Thread.currentThread().interrupt();
|
||
|
|
}
|
||
|
|
try {
|
||
|
|
addr = map0(imode, mapPosition, mapSize);
|
||
|
|
} catch (OutOfMemoryError y) {
|
||
|
|
// After a second OOME, fail
|
||
|
|
throw new IOException("Map failed", y);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// On Windows, and potentially other platforms, we need an open
|
||
|
|
// file descriptor for some mapping operations.
|
||
|
|
FileDescriptor mfd;
|
||
|
|
try {
|
||
|
|
mfd = nd.duplicateForMapping(fd);
|
||
|
|
} catch (IOException ioe) {
|
||
|
|
unmap0(addr, mapSize);
|
||
|
|
throw ioe;
|
||
|
|
}
|
||
|
|
|
||
|
|
assert (IOStatus.checkAll(addr));
|
||
|
|
assert (addr % allocationGranularity == 0);
|
||
|
|
int isize = (int)size;
|
||
|
|
Unmapper um = new Unmapper(addr, mapSize, isize, mfd);
|
||
|
|
if ((!writable) || (imode == MAP_RO)) {
|
||
|
|
return Util.newMappedByteBufferR(isize,
|
||
|
|
addr + pagePosition,
|
||
|
|
mfd,
|
||
|
|
um);
|
||
|
|
} else {
|
||
|
|
return Util.newMappedByteBuffer(isize,
|
||
|
|
addr + pagePosition,
|
||
|
|
mfd,
|
||
|
|
um);
|
||
|
|
}
|
||
|
|
} finally {
|
||
|
|
threads.remove(ti);
|
||
|
|
end(IOStatus.checkAll(addr));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Invoked by sun.management.ManagementFactoryHelper to create the management
|
||
|
|
* interface for mapped buffers.
|
||
|
|
*/
|
||
|
|
public static sun.misc.JavaNioAccess.BufferPool getMappedBufferPool() {
|
||
|
|
return new sun.misc.JavaNioAccess.BufferPool() {
|
||
|
|
@Override
|
||
|
|
public String getName() {
|
||
|
|
return "mapped";
|
||
|
|
}
|
||
|
|
@Override
|
||
|
|
public long getCount() {
|
||
|
|
return Unmapper.count;
|
||
|
|
}
|
||
|
|
@Override
|
||
|
|
public long getTotalCapacity() {
|
||
|
|
return Unmapper.totalCapacity;
|
||
|
|
}
|
||
|
|
@Override
|
||
|
|
public long getMemoryUsed() {
|
||
|
|
return Unmapper.totalSize;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
}
|
||
|
|
|
||
|
|
// -- Locks --
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
// keeps track of locks on this file
|
||
|
|
private volatile FileLockTable fileLockTable;
|
||
|
|
|
||
|
|
// indicates if file locks are maintained system-wide (as per spec)
|
||
|
|
private static boolean isSharedFileLockTable;
|
||
|
|
|
||
|
|
// indicates if the disableSystemWideOverlappingFileLockCheck property
|
||
|
|
// has been checked
|
||
|
|
private static volatile boolean propertyChecked;
|
||
|
|
|
||
|
|
// The lock list in J2SE 1.4/5.0 was local to each FileChannel instance so
|
||
|
|
// the overlap check wasn't system wide when there were multiple channels to
|
||
|
|
// the same file. This property is used to get 1.4/5.0 behavior if desired.
|
||
|
|
private static boolean isSharedFileLockTable() {
|
||
|
|
if (!propertyChecked) {
|
||
|
|
synchronized (FileChannelImpl.class) {
|
||
|
|
if (!propertyChecked) {
|
||
|
|
String value = AccessController.doPrivileged(
|
||
|
|
new GetPropertyAction(
|
||
|
|
"sun.nio.ch.disableSystemWideOverlappingFileLockCheck"));
|
||
|
|
isSharedFileLockTable = ((value == null) || value.equals("false"));
|
||
|
|
propertyChecked = true;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return isSharedFileLockTable;
|
||
|
|
}
|
||
|
|
|
||
|
|
private FileLockTable fileLockTable() throws IOException {
|
||
|
|
if (fileLockTable == null) {
|
||
|
|
synchronized (this) {
|
||
|
|
if (fileLockTable == null) {
|
||
|
|
if (isSharedFileLockTable()) {
|
||
|
|
int ti = threads.add();
|
||
|
|
try {
|
||
|
|
ensureOpen();
|
||
|
|
fileLockTable = FileLockTable.newSharedFileLockTable(this, fd);
|
||
|
|
} finally {
|
||
|
|
threads.remove(ti);
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
fileLockTable = new SimpleFileLockTable();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return fileLockTable;
|
||
|
|
}
|
||
|
|
|
||
|
|
public FileLock lock(long position, long size, boolean shared)
|
||
|
|
throws IOException
|
||
|
|
{
|
||
|
|
ensureOpen();
|
||
|
|
if (shared && !readable)
|
||
|
|
throw new NonReadableChannelException();
|
||
|
|
if (!shared && !writable)
|
||
|
|
throw new NonWritableChannelException();
|
||
|
|
FileLockImpl fli = new FileLockImpl(this, position, size, shared);
|
||
|
|
FileLockTable flt = fileLockTable();
|
||
|
|
flt.add(fli);
|
||
|
|
boolean completed = false;
|
||
|
|
int ti = -1;
|
||
|
|
try {
|
||
|
|
begin();
|
||
|
|
ti = threads.add();
|
||
|
|
if (!isOpen())
|
||
|
|
return null;
|
||
|
|
int n;
|
||
|
|
do {
|
||
|
|
n = nd.lock(fd, true, position, size, shared);
|
||
|
|
} while ((n == FileDispatcher.INTERRUPTED) && isOpen());
|
||
|
|
if (isOpen()) {
|
||
|
|
if (n == FileDispatcher.RET_EX_LOCK) {
|
||
|
|
assert shared;
|
||
|
|
FileLockImpl fli2 = new FileLockImpl(this, position, size,
|
||
|
|
false);
|
||
|
|
flt.replace(fli, fli2);
|
||
|
|
fli = fli2;
|
||
|
|
}
|
||
|
|
completed = true;
|
||
|
|
}
|
||
|
|
} finally {
|
||
|
|
if (!completed)
|
||
|
|
flt.remove(fli);
|
||
|
|
threads.remove(ti);
|
||
|
|
try {
|
||
|
|
end(completed);
|
||
|
|
} catch (ClosedByInterruptException e) {
|
||
|
|
throw new FileLockInterruptionException();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return fli;
|
||
|
|
}
|
||
|
|
|
||
|
|
public FileLock tryLock(long position, long size, boolean shared)
|
||
|
|
throws IOException
|
||
|
|
{
|
||
|
|
ensureOpen();
|
||
|
|
if (shared && !readable)
|
||
|
|
throw new NonReadableChannelException();
|
||
|
|
if (!shared && !writable)
|
||
|
|
throw new NonWritableChannelException();
|
||
|
|
FileLockImpl fli = new FileLockImpl(this, position, size, shared);
|
||
|
|
FileLockTable flt = fileLockTable();
|
||
|
|
flt.add(fli);
|
||
|
|
int result;
|
||
|
|
|
||
|
|
int ti = threads.add();
|
||
|
|
try {
|
||
|
|
try {
|
||
|
|
ensureOpen();
|
||
|
|
result = nd.lock(fd, false, position, size, shared);
|
||
|
|
} catch (IOException e) {
|
||
|
|
flt.remove(fli);
|
||
|
|
throw e;
|
||
|
|
}
|
||
|
|
if (result == FileDispatcher.NO_LOCK) {
|
||
|
|
flt.remove(fli);
|
||
|
|
return null;
|
||
|
|
}
|
||
|
|
if (result == FileDispatcher.RET_EX_LOCK) {
|
||
|
|
assert shared;
|
||
|
|
FileLockImpl fli2 = new FileLockImpl(this, position, size,
|
||
|
|
false);
|
||
|
|
flt.replace(fli, fli2);
|
||
|
|
return fli2;
|
||
|
|
}
|
||
|
|
return fli;
|
||
|
|
} finally {
|
||
|
|
threads.remove(ti);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void release(FileLockImpl fli) throws IOException {
|
||
|
|
int ti = threads.add();
|
||
|
|
try {
|
||
|
|
ensureOpen();
|
||
|
|
nd.release(fd, fli.position(), fli.size());
|
||
|
|
} finally {
|
||
|
|
threads.remove(ti);
|
||
|
|
}
|
||
|
|
assert fileLockTable != null;
|
||
|
|
fileLockTable.remove(fli);
|
||
|
|
}
|
||
|
|
|
||
|
|
// -- File lock support --
|
||
|
|
|
||
|
|
/**
|
||
|
|
* A simple file lock table that maintains a list of FileLocks obtained by a
|
||
|
|
* FileChannel. Use to get 1.4/5.0 behaviour.
|
||
|
|
*/
|
||
|
|
private static class SimpleFileLockTable extends FileLockTable {
|
||
|
|
// synchronize on list for access
|
||
|
|
private final List<FileLock> lockList = new ArrayList<FileLock>(2);
|
||
|
|
|
||
|
|
public SimpleFileLockTable() {
|
||
|
|
}
|
||
|
|
|
||
|
|
private void checkList(long position, long size)
|
||
|
|
throws OverlappingFileLockException
|
||
|
|
{
|
||
|
|
assert Thread.holdsLock(lockList);
|
||
|
|
for (FileLock fl: lockList) {
|
||
|
|
if (fl.overlaps(position, size)) {
|
||
|
|
throw new OverlappingFileLockException();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
public void add(FileLock fl) throws OverlappingFileLockException {
|
||
|
|
synchronized (lockList) {
|
||
|
|
checkList(fl.position(), fl.size());
|
||
|
|
lockList.add(fl);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
public void remove(FileLock fl) {
|
||
|
|
synchronized (lockList) {
|
||
|
|
lockList.remove(fl);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
public List<FileLock> removeAll() {
|
||
|
|
synchronized(lockList) {
|
||
|
|
List<FileLock> result = new ArrayList<FileLock>(lockList);
|
||
|
|
lockList.clear();
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
public void replace(FileLock fl1, FileLock fl2) {
|
||
|
|
synchronized (lockList) {
|
||
|
|
lockList.remove(fl1);
|
||
|
|
lockList.add(fl2);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// -- Native methods --
|
||
|
|
|
||
|
|
// Creates a new mapping
|
||
|
|
private long map0(int prot, long position, long length) throws IOException
|
||
|
|
{
|
||
|
|
FileStream fs = (FileStream)fd.getStream();
|
||
|
|
if (win32)
|
||
|
|
return mapViewOfFileWin32(fs, prot, position, length);
|
||
|
|
else
|
||
|
|
return mapViewOfFilePosix(fs, prot, position, length);
|
||
|
|
}
|
||
|
|
|
||
|
|
@cli.System.Security.SecuritySafeCriticalAttribute.Annotation
|
||
|
|
private static long mapViewOfFileWin32(FileStream fs, int prot, long position, long length) throws IOException
|
||
|
|
{
|
||
|
|
try
|
||
|
|
{
|
||
|
|
int PAGE_READONLY = 2;
|
||
|
|
int PAGE_READWRITE = 4;
|
||
|
|
int PAGE_WRITECOPY = 8;
|
||
|
|
|
||
|
|
int FILE_MAP_WRITE = 2;
|
||
|
|
int FILE_MAP_READ = 4;
|
||
|
|
int FILE_MAP_COPY = 1;
|
||
|
|
|
||
|
|
int fileProtect;
|
||
|
|
int mapAccess;
|
||
|
|
|
||
|
|
switch (prot)
|
||
|
|
{
|
||
|
|
case MAP_RO:
|
||
|
|
fileProtect = PAGE_READONLY;
|
||
|
|
mapAccess = FILE_MAP_READ;
|
||
|
|
break;
|
||
|
|
case MAP_RW:
|
||
|
|
fileProtect = PAGE_READWRITE;
|
||
|
|
mapAccess = FILE_MAP_WRITE;
|
||
|
|
break;
|
||
|
|
case MAP_PV:
|
||
|
|
fileProtect = PAGE_WRITECOPY;
|
||
|
|
mapAccess = FILE_MAP_COPY;
|
||
|
|
break;
|
||
|
|
default:
|
||
|
|
throw new Error();
|
||
|
|
}
|
||
|
|
|
||
|
|
long maxSize = length + position;
|
||
|
|
SafeFileHandle hFileMapping = CreateFileMapping(fs.get_SafeFileHandle(), IntPtr.Zero, fileProtect, (int)(maxSize >> 32), (int)maxSize, null);
|
||
|
|
int err = cli.System.Runtime.InteropServices.Marshal.GetLastWin32Error();
|
||
|
|
if (hFileMapping.get_IsInvalid())
|
||
|
|
{
|
||
|
|
throw new IOException("Win32 error " + err);
|
||
|
|
}
|
||
|
|
IntPtr p = MapViewOfFile(hFileMapping, mapAccess, (int)(position >> 32), (int)position, IntPtr.op_Explicit(length));
|
||
|
|
err = cli.System.Runtime.InteropServices.Marshal.GetLastWin32Error();
|
||
|
|
hFileMapping.Close();
|
||
|
|
if (p.Equals(IntPtr.Zero))
|
||
|
|
{
|
||
|
|
if (err == 8 /*ERROR_NOT_ENOUGH_MEMORY*/)
|
||
|
|
{
|
||
|
|
throw new OutOfMemoryError("Map failed");
|
||
|
|
}
|
||
|
|
throw new IOException("Win32 error " + err);
|
||
|
|
}
|
||
|
|
cli.System.GC.AddMemoryPressure(length);
|
||
|
|
return p.ToInt64();
|
||
|
|
}
|
||
|
|
finally
|
||
|
|
{
|
||
|
|
cli.System.GC.KeepAlive(fs);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
@cli.System.Security.SecuritySafeCriticalAttribute.Annotation
|
||
|
|
private static long mapViewOfFilePosix(FileStream fs, int prot, long position, long length) throws IOException
|
||
|
|
{
|
||
|
|
byte writeable = prot != MAP_RO ? (byte)1 : (byte)0;
|
||
|
|
byte copy_on_write = prot == MAP_PV ? (byte)1 : (byte)0;
|
||
|
|
IntPtr p = ikvm_mmap(fs.get_SafeFileHandle(), writeable, copy_on_write, position, (int)length);
|
||
|
|
cli.System.GC.KeepAlive(fs);
|
||
|
|
// HACK ikvm_mmap should really be changed to return a null pointer on failure,
|
||
|
|
// instead of whatever MAP_FAILED is defined to on the particular system we're running on,
|
||
|
|
// common values for MAP_FAILED are 0 and -1, so we test for these.
|
||
|
|
if (p.Equals(IntPtr.Zero) || p.Equals(new IntPtr(-1)))
|
||
|
|
{
|
||
|
|
throw new IOException("file mapping failed");
|
||
|
|
}
|
||
|
|
cli.System.GC.AddMemoryPressure(length);
|
||
|
|
return p.ToInt64();
|
||
|
|
}
|
||
|
|
|
||
|
|
@DllImportAttribute.Annotation(value="kernel32", SetLastError=true)
|
||
|
|
private static native SafeFileHandle CreateFileMapping(SafeFileHandle hFile, IntPtr lpAttributes, int flProtect, int dwMaximumSizeHigh, int dwMaximumSizeLow, String lpName);
|
||
|
|
|
||
|
|
@DllImportAttribute.Annotation(value="kernel32", SetLastError=true)
|
||
|
|
private static native IntPtr MapViewOfFile(SafeFileHandle hFileMapping, int dwDesiredAccess, int dwFileOffsetHigh, int dwFileOffsetLow, IntPtr dwNumberOfBytesToMap);
|
||
|
|
|
||
|
|
@DllImportAttribute.Annotation("kernel32")
|
||
|
|
private static native int UnmapViewOfFile(IntPtr lpBaseAddress);
|
||
|
|
|
||
|
|
@DllImportAttribute.Annotation("ikvm-native")
|
||
|
|
private static native int ikvm_munmap(IntPtr address, int size);
|
||
|
|
|
||
|
|
@DllImportAttribute.Annotation("ikvm-native")
|
||
|
|
private static native IntPtr ikvm_mmap(SafeFileHandle handle, byte writeable, byte copy_on_write, long position, int size);
|
||
|
|
|
||
|
|
// Removes an existing mapping
|
||
|
|
@cli.System.Security.SecuritySafeCriticalAttribute.Annotation
|
||
|
|
static int unmap0(long address, long length)
|
||
|
|
{
|
||
|
|
if (win32)
|
||
|
|
UnmapViewOfFile(IntPtr.op_Explicit(address));
|
||
|
|
else
|
||
|
|
ikvm_munmap(IntPtr.op_Explicit(address), (int)length);
|
||
|
|
cli.System.GC.RemoveMemoryPressure(length);
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Sets or reports this file's position
|
||
|
|
// If offset is -1, the current position is returned
|
||
|
|
// otherwise the position is set to offset
|
||
|
|
private static long position0(FileDescriptor fd, long offset) throws IOException
|
||
|
|
{
|
||
|
|
if (offset == -1)
|
||
|
|
{
|
||
|
|
return fd.getFilePointer();
|
||
|
|
}
|
||
|
|
fd.seek(offset);
|
||
|
|
return offset;
|
||
|
|
}
|
||
|
|
}
|