提交 ba8e659e 编写于 作者: C coffeys

7105952: Improve finalisation for FileInputStream/FileOutputStream/RandomAccessFile

Reviewed-by: alanb
上级 08e66185
......@@ -124,7 +124,7 @@ class FileInputStream extends InputStream
throw new NullPointerException();
}
fd = new FileDescriptor();
fd.incrementAndGetUseCount();
fd.attach(this);
open(name);
}
......@@ -164,10 +164,9 @@ class FileInputStream extends InputStream
/*
* FileDescriptor is being shared by streams.
* Ensure that it's GC'ed only when all the streams/channels are done
* using it.
* Register this stream with FileDescriptor tracker.
*/
fd.incrementAndGetUseCount();
fd.attach(this);
}
/**
......@@ -294,27 +293,14 @@ class FileInputStream extends InputStream
closed = true;
}
if (channel != null) {
/*
* Decrement the FD use count associated with the channel
* The use count is incremented whenever a new channel
* is obtained from this stream.
*/
fd.decrementAndGetUseCount();
channel.close();
}
/*
* Decrement the FD use count associated with this stream
*/
int useCount = fd.decrementAndGetUseCount();
/*
* If FileDescriptor is still in use by another stream, we
* will not close it.
*/
if (useCount <= 0) {
close0();
}
fd.closeAll(new Closeable() {
public void close() throws IOException {
close0();
}
});
}
/**
......@@ -328,7 +314,9 @@ class FileInputStream extends InputStream
* @see java.io.FileDescriptor
*/
public final FileDescriptor getFD() throws IOException {
if (fd != null) return fd;
if (fd != null) {
return fd;
}
throw new IOException();
}
......@@ -352,13 +340,6 @@ class FileInputStream extends InputStream
synchronized (this) {
if (channel == null) {
channel = FileChannelImpl.open(fd, true, false, this);
/*
* Increment fd's use count. Invoking the channel's close()
* method will result in decrementing the use count set for
* the channel.
*/
fd.incrementAndGetUseCount();
}
return channel;
}
......@@ -381,7 +362,12 @@ class FileInputStream extends InputStream
*/
protected void finalize() throws IOException {
if ((fd != null) && (fd != FileDescriptor.in)) {
close();
/* if fd is shared, the references in FileDescriptor
* will ensure that finalizer is only called when
* safe to do so. All references using the fd have
* become unreachable. We can call close()
*/
close();
}
}
}
......@@ -197,9 +197,9 @@ class FileOutputStream extends OutputStream
throw new NullPointerException();
}
this.fd = new FileDescriptor();
fd.attach(this);
this.append = append;
fd.incrementAndGetUseCount();
open(name, append);
}
......@@ -237,12 +237,7 @@ class FileOutputStream extends OutputStream
this.fd = fdObj;
this.append = false;
/*
* FileDescriptor is being shared by streams.
* Ensure that it's GC'ed only when all the streams/channels are done
* using it.
*/
fd.incrementAndGetUseCount();
fd.attach(this);
}
/**
......@@ -331,27 +326,14 @@ class FileOutputStream extends OutputStream
}
if (channel != null) {
/*
* Decrement FD use count associated with the channel
* The use count is incremented whenever a new channel
* is obtained from this stream.
*/
fd.decrementAndGetUseCount();
channel.close();
}
/*
* Decrement FD use count associated with this stream
*/
int useCount = fd.decrementAndGetUseCount();
/*
* If FileDescriptor is still in use by another stream, we
* will not close it.
*/
if (useCount <= 0) {
close0();
}
fd.closeAll(new Closeable() {
public void close() throws IOException {
close0();
}
});
}
/**
......@@ -365,7 +347,9 @@ class FileOutputStream extends OutputStream
* @see java.io.FileDescriptor
*/
public final FileDescriptor getFD() throws IOException {
if (fd != null) return fd;
if (fd != null) {
return fd;
}
throw new IOException();
}
......@@ -390,13 +374,6 @@ class FileOutputStream extends OutputStream
synchronized (this) {
if (channel == null) {
channel = FileChannelImpl.open(fd, false, true, append, this);
/*
* Increment fd's use count. Invoking the channel's close()
* method will result in decrementing the use count set for
* the channel.
*/
fd.incrementAndGetUseCount();
}
return channel;
}
......@@ -415,7 +392,12 @@ class FileOutputStream extends OutputStream
if (fd == FileDescriptor.out || fd == FileDescriptor.err) {
flush();
} else {
close();
/* if fd is shared, the references in FileDescriptor
* will ensure that finalizer is only called when
* safe to do so. All references using the fd have
* become unreachable. We can call close()
*/
close();
}
}
}
......
......@@ -229,7 +229,7 @@ public class RandomAccessFile implements DataOutput, DataInput, Closeable {
throw new NullPointerException();
}
fd = new FileDescriptor();
fd.incrementAndGetUseCount();
fd.attach(this);
open(name, imode);
}
......@@ -242,7 +242,9 @@ public class RandomAccessFile implements DataOutput, DataInput, Closeable {
* @see java.io.FileDescriptor
*/
public final FileDescriptor getFD() throws IOException {
if (fd != null) return fd;
if (fd != null) {
return fd;
}
throw new IOException();
}
......@@ -268,17 +270,6 @@ public class RandomAccessFile implements DataOutput, DataInput, Closeable {
synchronized (this) {
if (channel == null) {
channel = FileChannelImpl.open(fd, true, rw, this);
/*
* FileDescriptor could be shared by FileInputStream or
* FileOutputStream.
* Ensure that FD is GC'ed only when all the streams/channels
* are done using it.
* Increment fd's use count. Invoking the channel's close()
* method will result in decrementing the use count set for
* the channel.
*/
fd.incrementAndGetUseCount();
}
return channel;
}
......@@ -577,28 +568,14 @@ public class RandomAccessFile implements DataOutput, DataInput, Closeable {
closed = true;
}
if (channel != null) {
/*
* Decrement FD use count associated with the channel. The FD use
* count is incremented whenever a new channel is obtained from
* this stream.
*/
fd.decrementAndGetUseCount();
channel.close();
}
/*
* Decrement FD use count associated with this stream.
* The count got incremented by FileDescriptor during its construction.
*/
int useCount = fd.decrementAndGetUseCount();
/*
* If FileDescriptor is still in use by another stream, we
* will not close it.
*/
if (useCount <= 0) {
close0();
}
fd.closeAll(new Closeable() {
public void close() throws IOException {
close0();
}
});
}
//
......
/*
* Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 1995, 2011, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
......@@ -25,7 +25,8 @@
package java.io;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.ArrayList;
import java.util.List;
/**
* Instances of the file descriptor class serve as an opaque handle
......@@ -46,12 +47,9 @@ public final class FileDescriptor {
private int fd;
/**
* A counter for tracking the FIS/FOS/RAF instances that
* use this FileDescriptor. The FIS/FOS.finalize() will not release
* the FileDescriptor if it is still under user by a stream.
*/
private AtomicInteger useCount;
private Closeable parent;
private List<Closeable> otherParents;
private boolean closed;
/**
* Constructs an (invalid) FileDescriptor
......@@ -59,12 +57,10 @@ public final class FileDescriptor {
*/
public /**/ FileDescriptor() {
fd = -1;
useCount = new AtomicInteger();
}
private /* */ FileDescriptor(int fd) {
this.fd = fd;
useCount = new AtomicInteger();
}
/**
......@@ -164,13 +160,67 @@ public final class FileDescriptor {
);
}
// package private methods used by FIS, FOS and RAF
/*
* Package private methods to track referents.
* If multiple streams point to the same FileDescriptor, we cycle
* through the list of all referents and call close()
*/
int incrementAndGetUseCount() {
return useCount.incrementAndGet();
/**
* Attach a Closeable to this FD for tracking.
* parent reference is added to otherParents when
* needed to make closeAll simpler.
*/
synchronized void attach(Closeable c) {
if (parent == null) {
// first caller gets to do this
parent = c;
} else if (otherParents == null) {
otherParents = new ArrayList<>();
otherParents.add(parent);
otherParents.add(c);
} else {
otherParents.add(c);
}
}
int decrementAndGetUseCount() {
return useCount.decrementAndGet();
/**
* Cycle through all Closeables sharing this FD and call
* close() on each one.
*
* The caller closeable gets to call close0().
*/
@SuppressWarnings("try")
synchronized void closeAll(Closeable releaser) throws IOException {
if (!closed) {
closed = true;
IOException ioe = null;
try (Closeable c = releaser) {
if (otherParents != null) {
for (Closeable referent : otherParents) {
try {
referent.close();
} catch(IOException x) {
if (ioe == null) {
ioe = x;
} else {
ioe.addSuppressed(x);
}
}
}
}
} catch(IOException ex) {
/*
* If releaser close() throws IOException
* add other exceptions as suppressed.
*/
if (ioe != null)
ex.addSuppressed(ioe);
ioe = ex;
} finally {
if (ioe != null)
throw ioe;
}
}
}
}
/*
* Copyright (c) 2003, 2008, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
......@@ -25,7 +25,8 @@
package java.io;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.ArrayList;
import java.util.List;
/**
* Instances of the file descriptor class serve as an opaque handle
......@@ -45,13 +46,9 @@ public final class FileDescriptor {
private long handle;
/**
* A use counter for tracking the FIS/FOS/RAF instances that
* use this FileDescriptor. The FIS/FOS.finalize() will not release
* the FileDescriptor if it is still under use by any stream.
*/
private AtomicInteger useCount;
private Closeable parent;
private List<Closeable> otherParents;
private boolean closed;
/**
* Constructs an (invalid) FileDescriptor
......@@ -60,7 +57,6 @@ public final class FileDescriptor {
public /**/ FileDescriptor() {
fd = -1;
handle = -1;
useCount = new AtomicInteger();
}
static {
......@@ -168,13 +164,67 @@ public final class FileDescriptor {
return desc;
}
// package private methods used by FIS, FOS and RAF.
/*
* Package private methods to track referents.
* If multiple streams point to the same FileDescriptor, we cycle
* through the list of all referents and call close()
*/
int incrementAndGetUseCount() {
return useCount.incrementAndGet();
/**
* Attach a Closeable to this FD for tracking.
* parent reference is added to otherParents when
* needed to make closeAll simpler.
*/
synchronized void attach(Closeable c) {
if (parent == null) {
// first caller gets to do this
parent = c;
} else if (otherParents == null) {
otherParents = new ArrayList<>();
otherParents.add(parent);
otherParents.add(c);
} else {
otherParents.add(c);
}
}
int decrementAndGetUseCount() {
return useCount.decrementAndGet();
/**
* Cycle through all Closeables sharing this FD and call
* close() on each one.
*
* The caller closeable gets to call close0().
*/
@SuppressWarnings("try")
synchronized void closeAll(Closeable releaser) throws IOException {
if (!closed) {
closed = true;
IOException ioe = null;
try (Closeable c = releaser) {
if (otherParents != null) {
for (Closeable referent : otherParents) {
try {
referent.close();
} catch(IOException x) {
if (ioe == null) {
ioe = x;
} else {
ioe.addSuppressed(x);
}
}
}
}
} catch(IOException ex) {
/*
* If releaser close() throws IOException
* add other exceptions as suppressed.
*/
if (ioe != null)
ex.addSuppressed(ioe);
ioe = ex;
} finally {
if (ioe != null)
throw ioe;
}
}
}
}
/*
* Copyright (c) 2006, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/**
*
* @test
* @bug 6322678
* @summary Test for making sure that fd is closed during
* finalization of a stream, when an associated
* file channel is not available
*/
import java.io.*;
import java.nio.*;
import java.nio.channels.*;
public class FileChannelFDTest {
static byte data[] = new byte[] {48, 49, 50, 51, 52, 53, 54, 55, 56, 57,};
static String inFileName = "fd-in-test.txt";
static String outFileName = "fd-out-test.txt";
static File inFile;
static File outFile;
private static void writeToInFile() throws IOException {
FileOutputStream out = new FileOutputStream(inFile);
out.write(data);
out.close();
}
public static void main(String[] args)
throws Exception {
inFile= new File(System.getProperty("test.dir", "."),
inFileName);
inFile.createNewFile();
inFile.deleteOnExit();
writeToInFile();
outFile = new File(System.getProperty("test.dir", "."),
outFileName);
outFile.createNewFile();
outFile.deleteOnExit();
doFileChannel();
}
private static void doFileChannel() throws Exception {
FileInputStream fis = new FileInputStream(inFile);
FileDescriptor fd = fis.getFD();
FileChannel fc = fis.getChannel();
System.out.println("Created fis:" + fis);
/**
* Encourage the GC
*/
fis = null;
fc = null;
System.gc();
Thread.sleep(500);
if (fd.valid()) {
throw new Exception("Finalizer either didn't run --" +
"try increasing the Thread's sleep time after System.gc();" +
"or the finalizer didn't close the file");
}
System.out.println("File Closed successfully");
System.out.println();
}
}
......@@ -23,10 +23,9 @@
/*
* @test
* @bug 6322678 7082769
* @summary FileInputStream/FileOutputStream/RandomAccessFile allow file descriptor
* to be closed while still in use.
* @run main/othervm FileDescriptorSharing
* @bug 7105952 6322678 7082769
* @summary Improve finalisation for FileInputStream/FileOutputStream/RandomAccessFile
* @run main/othervm Sharing
*/
import java.io.*;
......@@ -34,7 +33,7 @@ import java.nio.channels.FileChannel;
import java.nio.channels.FileLock;
import java.util.concurrent.CountDownLatch;
public class FileDescriptorSharing {
public class Sharing {
final static int numFiles = 10;
volatile static boolean fail;
......@@ -44,11 +43,12 @@ public class FileDescriptorSharing {
TestMultipleFD();
TestIsValid();
MultiThreadedFD();
TestCloseAll();
}
/**
* We shouldn't discard a file descriptor until all streams have
* finished with it
* Finalizer shouldn't discard a file descriptor until all streams have
* finished with it.
*/
private static void TestFinalizer() throws Exception {
FileDescriptor fd = null;
......@@ -96,9 +96,6 @@ public class FileDescriptorSharing {
System.out.print(".");
ret = fis3.read();
}
if(!fd.valid()) {
throw new RuntimeException("TestFinalizer() : FileDescriptor should be valid");
}
} finally {
testFinalizerFile.delete();
}
......@@ -194,23 +191,19 @@ public class FileDescriptorSharing {
} finally {
try {
if (fis != null) fis.close();
if (fos != null) fos.close();
if (!fd.valid()) {
throw new RuntimeException("FileDescriptor should be valid");
}
if (raf != null) raf.close();
if (fd.valid()) {
throw new RuntimeException("close() called and FileDescriptor still valid");
throw new RuntimeException("[FIS close()] FileDescriptor shouldn't be valid");
}
} finally {
if (fos != null) fos.close();
if (raf != null) raf.close();
} finally {
test1.delete();
}
}
/*
* Close out in different order to ensure FD is not
* closed out too early
* Close out in different order to ensure FD is
* closed correctly.
*/
File test2 = new File("test2");
try {
......@@ -221,14 +214,11 @@ public class FileDescriptorSharing {
} finally {
try {
if (raf != null) raf.close();
if (fos != null) fos.close();
if (!fd.valid()) {
throw new RuntimeException("FileDescriptor should be valid");
}
if (fis != null) fis.close();
if (fd.valid()) {
throw new RuntimeException("close() called and FileDescriptor still valid");
throw new RuntimeException("[RAF close()] FileDescriptor shouldn't be valid");
}
if (fos != null) fos.close();
if (fis != null) fis.close();
} finally {
test2.delete();
}
......@@ -244,14 +234,11 @@ public class FileDescriptorSharing {
} finally {
try {
if (fos != null) fos.close();
if (raf != null) raf.close();
if (!fd.valid()) {
throw new RuntimeException("FileDescriptor should be valid");
}
if (fis != null) fis.close();
if (fd.valid()) {
throw new RuntimeException("close() called and FileDescriptor still valid");
throw new RuntimeException("[FOS close()] FileDescriptor shouldn't be valid");
}
if (raf != null) raf.close();
if (fis != null) fis.close();
} finally {
test3.delete();
}
......@@ -259,7 +246,7 @@ public class FileDescriptorSharing {
}
/**
* Test concurrent access to the same fd.useCount field
* Test concurrent access to the same FileDescriptor
*/
private static void MultiThreadedFD() throws Exception {
RandomAccessFile raf = null;
......@@ -293,6 +280,68 @@ public class FileDescriptorSharing {
}
}
/**
* Test closeAll handling in FileDescriptor
*/
private static void TestCloseAll() throws Exception {
File testFile = new File("test");
testFile.deleteOnExit();
RandomAccessFile raf = new RandomAccessFile(testFile, "rw");
FileInputStream fis = new FileInputStream(raf.getFD());
fis.close();
if (raf.getFD().valid()) {
throw new RuntimeException("FD should not be valid.");
}
// Test the suppressed exception handling - FileInputStream
raf = new RandomAccessFile(testFile, "rw");
fis = new FileInputStream(raf.getFD());
BadFileInputStream bfis1 = new BadFileInputStream(raf.getFD());
BadFileInputStream bfis2 = new BadFileInputStream(raf.getFD());
BadFileInputStream bfis3 = new BadFileInputStream(raf.getFD());
// extra test - set bfis3 to null
bfis3 = null;
try {
fis.close();
} catch (IOException ioe) {
ioe.printStackTrace();
if (ioe.getSuppressed().length != 2) {
throw new RuntimeException("[FIS]Incorrect number of suppressed " +
"exceptions received : " + ioe.getSuppressed().length);
}
}
if (raf.getFD().valid()) {
// we should still have closed the FD
// even with the exception.
throw new RuntimeException("[FIS]TestCloseAll : FD still valid.");
}
// Now test with FileOutputStream
raf = new RandomAccessFile(testFile, "rw");
FileOutputStream fos = new FileOutputStream(raf.getFD());
BadFileOutputStream bfos1 = new BadFileOutputStream(raf.getFD());
BadFileOutputStream bfos2 = new BadFileOutputStream(raf.getFD());
BadFileOutputStream bfos3 = new BadFileOutputStream(raf.getFD());
// extra test - set bfos3 to null
bfos3 = null;
try {
fos.close();
} catch (IOException ioe) {
ioe.printStackTrace();
if (ioe.getSuppressed().length != 2) {
throw new RuntimeException("[FOS]Incorrect number of suppressed " +
"exceptions received : " + ioe.getSuppressed().length);
}
}
if (raf.getFD().valid()) {
// we should still have closed the FD
// even with the exception.
throw new RuntimeException("[FOS]TestCloseAll : FD still valid.");
}
}
/**
* A thread which will open and close a number of FileInputStreams and
* FileOutputStreams referencing the same native file descriptor.
......@@ -325,12 +374,35 @@ public class FileDescriptorSharing {
System.out.println("OpenClose encountered IO issue :" + ioe);
fail = true;
} finally {
if (!fd.valid()) { // fd should still be valid given RAF reference
System.out.println("OpenClose: FileDescriptor should be valid");
if (fd.valid()) { // fd should not be valid after first close() call
System.out.println("OpenClose: FileDescriptor shouldn't be valid");
fail = true;
}
done.countDown();
}
}
}
private static class BadFileInputStream extends FileInputStream {
BadFileInputStream(FileDescriptor fd) {
super(fd);
}
public void close() throws IOException {
throw new IOException("Bad close operation");
}
}
private static class BadFileOutputStream extends FileOutputStream {
BadFileOutputStream(FileDescriptor fd) {
super(fd);
}
public void close() throws IOException {
throw new IOException("Bad close operation");
}
}
}
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