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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
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*
* 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.
*
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package jdk.jfr.internal.consumer;
import java.io.DataInput;
import java.io.EOFException;
import java.io.File;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.file.Path;
public final class RecordingInput implements DataInput, AutoCloseable {
private final static int DEFAULT_BLOCK_SIZE = 64_000;
private static final class Block {
private byte[] bytes = new byte[0];
private long blockPosition;
private long blockPositionEnd;
boolean contains(long position) {
return position >= blockPosition && position < blockPositionEnd;
}
public void read(RandomAccessFile file, int amount) throws IOException {
blockPosition = file.getFilePointer();
// reuse byte array, if possible
if (amount > bytes.length) {
bytes = new byte[amount];
}
this.blockPositionEnd = blockPosition + amount;
file.readFully(bytes, 0, amount);
}
public byte get(long position) {
return bytes[(int) (position - blockPosition)];
}
public void reset() {
blockPosition = 0;
blockPositionEnd = 0;
}
}
private final int blockSize;
private final FileAccess fileAccess;
private RandomAccessFile file;
private String filename;
private Block currentBlock = new Block();
private Block previousBlock = new Block();
private long position;
private long size = -1; // Fail fast if setSize(...) has not been called
// before parsing
RecordingInput(File f, FileAccess fileAccess, int blockSize) throws IOException {
this.blockSize = blockSize;
this.fileAccess = fileAccess;
initialize(f);
}
private void initialize(File f) throws IOException {
this.filename = fileAccess.getAbsolutePath(f);
this.file = fileAccess.openRAF(f, "r");
this.position = 0;
this.size = -1;
this.currentBlock.reset();
previousBlock.reset();
if (fileAccess.length(f) < 8) {
throw new IOException("Not a valid Flight Recorder file. File length is only " + fileAccess.length(f) + " bytes.");
}
}
public RecordingInput(File f, FileAccess fileAccess) throws IOException {
this(f, fileAccess, DEFAULT_BLOCK_SIZE);
}
void positionPhysical(long position) throws IOException {
file.seek(position);
}
byte readPhysicalByte() throws IOException {
return file.readByte();
}
long readPhysicalLong() throws IOException {
return file.readLong();
}
@Override
public final byte readByte() throws IOException {
if (!currentBlock.contains(position)) {
position(position);
}
return currentBlock.get(position++);
}
@Override
public final void readFully(byte[] dest, int offset, int length) throws IOException {
// TODO: Optimize, use Arrays.copy if all bytes are in current block
// array
for (int i = 0; i < length; i++) {
dest[i + offset] = readByte();
}
}
@Override
public final void readFully(byte[] dst) throws IOException {
readFully(dst, 0, dst.length);
}
short readRawShort() throws IOException {
// copied from java.io.Bits
byte b0 = readByte();
byte b1 = readByte();
return (short) ((b1 & 0xFF) + (b0 << 8));
}
@Override
public double readDouble() throws IOException {
// copied from java.io.Bits
return Double.longBitsToDouble(readRawLong());
}
@Override
public float readFloat() throws IOException {
// copied from java.io.Bits
return Float.intBitsToFloat(readRawInt());
}
int readRawInt() throws IOException {
// copied from java.io.Bits
byte b0 = readByte();
byte b1 = readByte();
byte b2 = readByte();
byte b3 = readByte();
return ((b3 & 0xFF)) + ((b2 & 0xFF) << 8) + ((b1 & 0xFF) << 16) + ((b0) << 24);
}
long readRawLong() throws IOException {
// copied from java.io.Bits
byte b0 = readByte();
byte b1 = readByte();
byte b2 = readByte();
byte b3 = readByte();
byte b4 = readByte();
byte b5 = readByte();
byte b6 = readByte();
byte b7 = readByte();
return ((b7 & 0xFFL)) + ((b6 & 0xFFL) << 8) + ((b5 & 0xFFL) << 16) + ((b4 & 0xFFL) << 24) + ((b3 & 0xFFL) << 32) + ((b2 & 0xFFL) << 40) + ((b1 & 0xFFL) << 48) + (((long) b0) << 56);
}
public final long position() {
return position;
}
public final void position(long newPosition) throws IOException {
if (!currentBlock.contains(newPosition)) {
if (!previousBlock.contains(newPosition)) {
if (newPosition > size) {
throw new EOFException("Trying to read at " + newPosition + ", but file is only " + size + " bytes.");
}
long blockStart = trimToFileSize(calculateBlockStart(newPosition));
file.seek(blockStart);
// trim amount to file size
long amount = Math.min(size - blockStart, blockSize);
previousBlock.read(file, (int) amount);
}
// swap previous and current
Block tmp = currentBlock;
currentBlock = previousBlock;
previousBlock = tmp;
}
position = newPosition;
}
private final long trimToFileSize(long position) throws IOException {
return Math.min(size(), Math.max(0, position));
}
private final long calculateBlockStart(long newPosition) {
// align to end of current block
if (currentBlock.contains(newPosition - blockSize)) {
return currentBlock.blockPosition + currentBlock.bytes.length;
}
// align before current block
if (currentBlock.contains(newPosition + blockSize)) {
return currentBlock.blockPosition - blockSize;
}
// not near current block, pick middle
return newPosition - blockSize / 2;
}
long size() {
return size;
}
@Override
public void close() throws IOException {
file.close();
}
@Override
public final int skipBytes(int n) throws IOException {
long position = position();
position(position + n);
return (int) (position() - position);
}
@Override
public final boolean readBoolean() throws IOException {
return readByte() != 0;
}
@Override
public int readUnsignedByte() throws IOException {
return readByte() & 0x00FF;
}
@Override
public int readUnsignedShort() throws IOException {
return readShort() & 0xFFFF;
}
@Override
public final String readLine() throws IOException {
throw new UnsupportedOperationException();
}
// NOTE, this method should really be called readString
// but can't be renamed without making RecordingInput a
// public class.
//
// This method DOES Not read as expected (s2 + utf8 encoded character)
// instead it read:
// byte encoding
// int size
// data (byte or char)
//
// where encoding
//
// 0, means null
// 1, means UTF8 encoded byte array
// 2, means char array
// 3, means latin-1 (ISO-8859-1) encoded byte array
// 4, means ""
@Override
public String readUTF() throws IOException {
throw new UnsupportedOperationException("Use StringParser");
}
@Override
public char readChar() throws IOException {
return (char) readLong();
}
@Override
public short readShort() throws IOException {
return (short) readLong();
}
@Override
public int readInt() throws IOException {
return (int) readLong();
}
@Override
public long readLong() throws IOException {
final byte[] bytes = currentBlock.bytes;
final int index = (int) (position - currentBlock.blockPosition);
if (index + 8 < bytes.length && index >= 0) {
byte b0 = bytes[index];
long ret = (b0 & 0x7FL);
if (b0 >= 0) {
position += 1;
return ret;
}
int b1 = bytes[index + 1];
ret += (b1 & 0x7FL) << 7;
if (b1 >= 0) {
position += 2;
return ret;
}
int b2 = bytes[index + 2];
ret += (b2 & 0x7FL) << 14;
if (b2 >= 0) {
position += 3;
return ret;
}
int b3 = bytes[index + 3];
ret += (b3 & 0x7FL) << 21;
if (b3 >= 0) {
position += 4;
return ret;
}
int b4 = bytes[index + 4];
ret += (b4 & 0x7FL) << 28;
if (b4 >= 0) {
position += 5;
return ret;
}
int b5 = bytes[index + 5];
ret += (b5 & 0x7FL) << 35;
if (b5 >= 0) {
position += 6;
return ret;
}
int b6 = bytes[index + 6];
ret += (b6 & 0x7FL) << 42;
if (b6 >= 0) {
position += 7;
return ret;
}
int b7 = bytes[index + 7];
ret += (b7 & 0x7FL) << 49;
if (b7 >= 0) {
position += 8;
return ret;
}
int b8 = bytes[index + 8];// read last byte raw
position += 9;
return ret + (((long) (b8 & 0XFF)) << 56);
} else {
return readLongSlow();
}
}
private long readLongSlow() throws IOException {
byte b0 = readByte();
long ret = (b0 & 0x7FL);
if (b0 >= 0) {
return ret;
}
int b1 = readByte();
ret += (b1 & 0x7FL) << 7;
if (b1 >= 0) {
return ret;
}
int b2 = readByte();
ret += (b2 & 0x7FL) << 14;
if (b2 >= 0) {
return ret;
}
int b3 = readByte();
ret += (b3 & 0x7FL) << 21;
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