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/*
* Copyright 2015 Odnoklassniki Ltd, Mail.Ru Group
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package one.nio.mem;
import java.lang.reflect.Constructor;
import one.nio.os.Mem;
import one.nio.serial.DataStream;
import one.nio.util.JavaInternals;
import java.io.Closeable;
import java.io.FileDescriptor;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.nio.ByteOrder;
import java.nio.MappedByteBuffer;
public class MappedFile implements Closeable {
private static final Method force0 = JavaInternals.getMethod(MappedByteBuffer.class, "force0", FileDescriptor.class, long.class, long.class);
private static final int STATE_CLOSED = 0;
private static final int STATE_MALLOC = 1;
private static final int STATE_MMAP = 2;
public static final int MAP_RO = 0;
public static final int MAP_RW = 1;
public static final int MAP_PV = 2;
private final RandomAccessFile file;
private final long addr;
private final long size;
private int mode;
private int state;
public MappedFile(long size) {
this.file = null;
this.addr = DirectMemory.allocateRaw(size);
this.size = size;
this.mode = MAP_RW;
this.state = STATE_MALLOC;
}
public MappedFile(String name, long size) throws IOException {
this(name, size, MAP_RW);
}
public MappedFile(String name, long size, int mode) throws IOException {
this.file = new RandomAccessFile(name, mode == MAP_RW ? "rw" : "r");
try {
if (size == 0) {
size = file.length();
} else if (mode == MAP_RW) {
file.setLength(size);
}
this.addr = map(file, mode, 0, size);
this.size = size;
this.mode = mode;
this.state = STATE_MMAP;
} catch (IOException e) {
file.close();
throw e;
}
}
public void sync() throws IOException {
if (state != STATE_MMAP || mode != MAP_RW) {
return;
}
if (Mem.IS_SUPPORTED) {
int err = Mem.msync(addr, size, Mem.MS_SYNC);
if (err != 0) {
throw new IOException("msync failed: " + err);
}
} else {
try {
force0.invoke(DirectMemory.prototype, file.getFD(), addr, size);
} catch (IllegalAccessException e) {
throw new IllegalStateException(e);
} catch (InvocationTargetException e) {
Throwable target = e.getTargetException();
throw (target instanceof IOException) ? (IOException) target : new IOException(target);
}
}
}
public void makeReadonly() throws IOException {
if (state != STATE_MMAP || mode != MAP_RW) {
throw new IllegalStateException();
}
if (Mem.IS_SUPPORTED) {
int err = Mem.mprotect(addr, size, Mem.PROT_READ);
if (err != 0) {
throw new IOException("mprotect failed: " + err);
}
}
this.mode = MAP_RO;
}
public void close() {
if (state == STATE_MALLOC) {
DirectMemory.freeRaw(addr);
} else if (state == STATE_MMAP) {
unmap(addr, size);
try {
file.close();
} catch (IOException ignore) {
}
}
state = STATE_CLOSED;
}
public final RandomAccessFile getFile() {
return file;
}
public final long getAddr() {
return addr;
}
public final long getSize() {
return size;
}
public int getMode() {
return mode;
}
public DataStream dataStream(ByteOrder order) {
if (ByteOrder.nativeOrder().equals(order)) {
throw new UnsupportedOperationException("Native byte order is not implemeneted");
}
return new DataStream(addr, size);
}
public static long map(RandomAccessFile f, int mode, long start, long size) throws IOException {
if (Mem.IS_SUPPORTED) {
int prot = (mode == MAP_RO) ? Mem.PROT_READ : Mem.PROT_READ | Mem.PROT_WRITE;
int flags = (mode == MAP_PV) ? Mem.MAP_PRIVATE : Mem.MAP_SHARED;
long result = Mem.mmap(0, size, prot, flags, f.getFD(), start);
if (result != -1) {
return result;
}
}
try {
Class> fileChannelImplClass = JavaInternals.getClass("sun.nio.ch.FileChannelImpl");
if (fileChannelImplClass != null) {
Method map0 = JavaInternals.getMethod(
fileChannelImplClass, "map0", int.class, long.class, long.class
);
if (map0 != null) {
return (long) map0.invoke(f.getChannel(), mode, start, size);
}
// Newer JDK has an extra 'sync' argument
map0 = JavaInternals.getMethod(
fileChannelImplClass, "map0", int.class, long.class, long.class, boolean.class
);
if (map0 != null) {
return (long) map0.invoke(f.getChannel(), mode, start, size, false);
}
// Since 19 JDK has an extra 'file descriptor' argument
map0 = JavaInternals.getMethod(
fileChannelImplClass, "map0", FileDescriptor.class, int.class, long.class, long.class, boolean.class
);
if (map0 != null) {
return (long) map0.invoke(f.getChannel(), f.getFD(), mode, start, size, false);
}
}
// JDKs since 20 have the `map0` method moved into the new `FileDispatcherImpl` class as `map`
// In reality, the `static native long map0` method is still available via `UnixFileDispatcherImpl`
// so it is also probed as an alternative (we don't know which one will get removed earlier /shrug)
// See https://github.com/openjdk/jdk/commit/48cc15602b62e81bb179ca9570a1e7d8bbf4d6df
Class> fileDispatcherImplClass = JavaInternals.getClass("sun.nio.ch.FileDispatcherImpl");
if (fileDispatcherImplClass != null) {
Method map0 = JavaInternals.getMethodRecursively(fileDispatcherImplClass,
"map", FileDescriptor.class, int.class, long.class, long.class, boolean.class
);
if (map0 != null) {
Constructor> fileDispatcherImplConstructor = JavaInternals.getConstructor(fileDispatcherImplClass);
if (fileDispatcherImplConstructor != null) {
Object fileDispatcherImpl = fileDispatcherImplConstructor.newInstance();
return (long) map0.invoke(
fileDispatcherImpl,
f.getFD(), mode, start, size, false
);
}
}
}
Class> unixFileDispatcherImplClass = JavaInternals.getClass("sun.nio.ch.UnixFileDispatcherImpl");
if (unixFileDispatcherImplClass != null) {
Method map0 = JavaInternals.getMethod(
unixFileDispatcherImplClass, "map0", FileDescriptor.class, int.class, long.class, long.class, boolean.class
);
if (map0 != null) {
return (long) map0.invoke(null, f.getFD(), mode, start, size, false);
}
// we also probe the non-static `map` method on this class...
map0 = JavaInternals.getMethodRecursively(
unixFileDispatcherImplClass, "map", FileDescriptor.class, int.class, long.class, long.class, boolean.class
);
if (map0 != null) {
Constructor> unixFileDispatcherImplConstructor = JavaInternals.getConstructor(unixFileDispatcherImplClass);
if (unixFileDispatcherImplConstructor != null) {
Object unixFileDispatcherImplObject = unixFileDispatcherImplConstructor.newInstance();
return (long) map0.invoke(unixFileDispatcherImplObject,
f.getFD(), mode, start, size, false
);
}
}
}
throw new IllegalStateException("map0 method not found");
} catch (InvocationTargetException e) {
Throwable target = e.getTargetException();
throw (target instanceof IOException) ? (IOException) target : new IOException(target);
} catch (ReflectiveOperationException e) {
throw new IllegalStateException(e);
}
}
public static void unmap(long start, long size) {
if (Mem.IS_SUPPORTED) {
if (Mem.munmap(start, size) == 0) {
return;
}
}
try {
Class> fileChannelImplClass = JavaInternals.getClass("sun.nio.ch.FileChannelImpl");
if (fileChannelImplClass != null) {
Method unmap0 = JavaInternals.getMethod(fileChannelImplClass, "unmap0", long.class, long.class);
if (unmap0 != null) {
unmap0.invoke(null, start, size);
return;
}
}
// JDKs since 20 have the `unmap0` method moved into the new `FileDispatcherImpl` class as `unmap`
// In reality, the `static native long unmap0` method is still available via `UnixFileDispatcherImpl`
// so it is also probed as an alternative (we don't know which one will get removed earlier /shrug)
// See https://github.com/openjdk/jdk/commit/48cc15602b62e81bb179ca9570a1e7d8bbf4d6df
Class> fileDispatcherImplClass = JavaInternals.getClass("sun.nio.ch.FileDispatcherImpl");
if (fileDispatcherImplClass != null) {
Method unmap0 = JavaInternals.getMethodRecursively(fileDispatcherImplClass, "unmap", long.class, long.class);
if (unmap0 != null) {
Constructor> fileDispatcherImplConstructor = JavaInternals.getConstructor(fileDispatcherImplClass);
if (fileDispatcherImplConstructor != null) {
Object fileDispatcherImpl = fileDispatcherImplConstructor.newInstance();
unmap0.invoke(fileDispatcherImpl, start, size);
return;
}
}
}
Class> unixFileDispatcherImplClass = JavaInternals.getClass("sun.nio.ch.UnixFileDispatcherImpl");
if (unixFileDispatcherImplClass != null) {
Method unmap0 = JavaInternals.getMethod(
unixFileDispatcherImplClass, "map0", FileDescriptor.class, int.class, long.class, long.class, boolean.class
);
if (unmap0 != null) {
unmap0.invoke(null, start, size);
return;
}
// we also probe the non-static `map` method on this class...
unmap0 = JavaInternals.getMethodRecursively(unixFileDispatcherImplClass, "unmap", long.class, long.class);
if (unmap0 != null) {
Constructor> unixFileDispatcherImplConstructor = JavaInternals.getConstructor(unixFileDispatcherImplClass);
if (unixFileDispatcherImplConstructor != null) {
Object unixFileDispatcherImplObject = unixFileDispatcherImplConstructor.newInstance();
unmap0.invoke(unixFileDispatcherImplObject, start, size);
return;
}
}
}
throw new IllegalStateException("unmap0 method not found");
} catch (ReflectiveOperationException e) {
throw new IllegalStateException(e);
}
}
}
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