/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.hadoop.hbase.io.util;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.util.Pair;
import com.google.common.base.Preconditions;
/*
* It seems like as soon as somebody sets himself to the task of creating VInt encoding, his mind
* blanks out for a split-second and he starts the work by wrapping it in the most convoluted
* interface he can come up with. Custom streams that allocate memory, DataOutput that is only used
* to write single bytes... We operate on simple streams. Thus, we are going to have a simple
* implementation copy-pasted from protobuf Coded*Stream.
*/
@InterfaceAudience.Private
public class StreamUtils {
public static void writeRawVInt32(OutputStream output, int value) throws IOException {
while (true) {
if ((value & ~0x7F) == 0) {
output.write(value);
return;
} else {
output.write((value & 0x7F) | 0x80);
value >>>= 7;
}
}
}
public static int readRawVarint32(InputStream input) throws IOException {
byte tmp = (byte) input.read();
if (tmp >= 0) {
return tmp;
}
int result = tmp & 0x7f;
if ((tmp = (byte) input.read()) >= 0) {
result |= tmp << 7;
} else {
result |= (tmp & 0x7f) << 7;
if ((tmp = (byte) input.read()) >= 0) {
result |= tmp << 14;
} else {
result |= (tmp & 0x7f) << 14;
if ((tmp = (byte) input.read()) >= 0) {
result |= tmp << 21;
} else {
result |= (tmp & 0x7f) << 21;
result |= (tmp = (byte) input.read()) << 28;
if (tmp < 0) {
// Discard upper 32 bits.
for (int i = 0; i < 5; i++) {
if (input.read() >= 0) {
return result;
}
}
throw new IOException("Malformed varint");
}
}
}
}
return result;
}
public static int readRawVarint32(ByteBuffer input) throws IOException {
byte tmp = input.get();
if (tmp >= 0) {
return tmp;
}
int result = tmp & 0x7f;
if ((tmp = input.get()) >= 0) {
result |= tmp << 7;
} else {
result |= (tmp & 0x7f) << 7;
if ((tmp = input.get()) >= 0) {
result |= tmp << 14;
} else {
result |= (tmp & 0x7f) << 14;
if ((tmp = input.get()) >= 0) {
result |= tmp << 21;
} else {
result |= (tmp & 0x7f) << 21;
result |= (tmp = input.get()) << 28;
if (tmp < 0) {
// Discard upper 32 bits.
for (int i = 0; i < 5; i++) {
if (input.get() >= 0) {
return result;
}
}
throw new IOException("Malformed varint");
}
}
}
}
return result;
}
/**
* Reads a varInt value stored in an array.
*
* @param input
* Input array where the varInt is available
* @param offset
* Offset in the input array where varInt is available
* @return A pair of integers in which first value is the actual decoded varInt value and second
* value as number of bytes taken by this varInt for it's storage in the input array.
* @throws IOException
*/
public static Pair<Integer, Integer> readRawVarint32(byte[] input, int offset) throws IOException {
int newOffset = offset;
byte tmp = input[newOffset++];
if (tmp >= 0) {
return new Pair<Integer, Integer>((int) tmp, newOffset - offset);
}
int result = tmp & 0x7f;
tmp = input[newOffset++];
if (tmp >= 0) {
result |= tmp << 7;
} else {
result |= (tmp & 0x7f) << 7;
tmp = input[newOffset++];
if (tmp >= 0) {
result |= tmp << 14;
} else {
result |= (tmp & 0x7f) << 14;
tmp = input[newOffset++];
if (tmp >= 0) {
result |= tmp << 21;
} else {
result |= (tmp & 0x7f) << 21;
tmp = input[newOffset++];
result |= tmp << 28;
if (tmp < 0) {
// Discard upper 32 bits.
for (int i = 0; i < 5; i++) {
tmp = input[newOffset++];
if (tmp >= 0) {
return new Pair<Integer, Integer>(result, newOffset - offset);
}
}
throw new IOException("Malformed varint");
}
}
}
}
return new Pair<Integer, Integer>(result, newOffset - offset);
}
public static short toShort(byte hi, byte lo) {
short s = (short) (((hi & 0xFF) << 8) | (lo & 0xFF));
Preconditions.checkArgument(s >= 0);
return s;
}
public static void writeShort(OutputStream out, short v) throws IOException {
Preconditions.checkArgument(v >= 0);
out.write((byte) (0xff & (v >> 8)));
out.write((byte) (0xff & v));
}
public static void writeInt(OutputStream out, int v) throws IOException {
out.write((byte) (0xff & (v >> 24)));
out.write((byte) (0xff & (v >> 16)));
out.write((byte) (0xff & (v >> 8)));
out.write((byte) (0xff & v));
}
public static void writeLong(OutputStream out, long v) throws IOException {
out.write((byte) (0xff & (v >> 56)));
out.write((byte) (0xff & (v >> 48)));
out.write((byte) (0xff & (v >> 40)));
out.write((byte) (0xff & (v >> 32)));
out.write((byte) (0xff & (v >> 24)));
out.write((byte) (0xff & (v >> 16)));
out.write((byte) (0xff & (v >> 8)));
out.write((byte) (0xff & v));
}
}