/**
* Copyright 2012 Nikita Koksharov
*
* 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 com.corundumstudio.socketio.protocol;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufAllocator;
import io.netty.buffer.ByteBufOutputStream;
import io.netty.buffer.Unpooled;
import io.netty.handler.codec.base64.Base64;
import io.netty.handler.codec.base64.Base64Dialect;
import io.netty.util.CharsetUtil;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Queue;
import com.corundumstudio.socketio.Configuration;
public class PacketEncoder {
private static final byte[] BINARY_HEADER = "b4".getBytes(CharsetUtil.UTF_8);
private static final byte[] B64_DELIMITER = new byte[] {':'};
private static final byte[] JSONP_HEAD = "___eio[".getBytes(CharsetUtil.UTF_8);
private static final byte[] JSONP_START = "]('".getBytes(CharsetUtil.UTF_8);
private static final byte[] JSONP_END = "');".getBytes(CharsetUtil.UTF_8);
private final JsonSupport jsonSupport;
private final Configuration configuration;
public PacketEncoder(Configuration configuration, JsonSupport jsonSupport) {
this.jsonSupport = jsonSupport;
this.configuration = configuration;
}
public JsonSupport getJsonSupport() {
return jsonSupport;
}
public ByteBuf allocateBuffer(ByteBufAllocator allocator) {
if (configuration.isPreferDirectBuffer()) {
return allocator.ioBuffer();
}
return allocator.heapBuffer();
}
public void encodeJsonP(Integer jsonpIndex, Queue<Packet> packets, ByteBuf out, ByteBufAllocator allocator, int limit) throws IOException {
boolean jsonpMode = jsonpIndex != null;
ByteBuf buf = allocateBuffer(allocator);
int i = 0;
while (true) {
Packet packet = packets.poll();
if (packet == null || i == limit) {
break;
}
ByteBuf packetBuf = allocateBuffer(allocator);
encodePacket(packet, packetBuf, allocator, true);
int packetSize = packetBuf.writerIndex();
buf.writeBytes(toChars(packetSize));
buf.writeBytes(B64_DELIMITER);
buf.writeBytes(packetBuf);
packetBuf.release();
i++;
for (ByteBuf attachment : packet.getAttachments()) {
ByteBuf encodedBuf = Base64.encode(attachment, Base64Dialect.URL_SAFE);
buf.writeBytes(toChars(encodedBuf.readableBytes() + 2));
buf.writeBytes(B64_DELIMITER);
buf.writeBytes(BINARY_HEADER);
buf.writeBytes(encodedBuf);
}
}
if (jsonpMode) {
out.writeBytes(JSONP_HEAD);
out.writeBytes(toChars(jsonpIndex));
out.writeBytes(JSONP_START);
}
processUtf8(buf, out, jsonpMode);
buf.release();
if (jsonpMode) {
out.writeBytes(JSONP_END);
}
}
private void processUtf8(ByteBuf in, ByteBuf out, boolean jsonpMode) {
while (in.isReadable()) {
short value = (short) (in.readByte() & 0xFF);
if (value >>> 7 == 0) {
if (jsonpMode && (value == '\\' || value == '\'')) {
out.writeByte('\\');
}
out.writeByte(value);
} else {
out.writeByte(((value >>> 6) | 0xC0));
out.writeByte(((value & 0x3F) | 0x80));
}
}
}
public void encodePackets(Queue<Packet> packets, ByteBuf buffer, ByteBufAllocator allocator, int limit) throws IOException {
int i = 0;
while (true) {
Packet packet = packets.poll();
if (packet == null || i == limit) {
break;
}
encodePacket(packet, buffer, allocator, false);
i++;
for (ByteBuf attachment : packet.getAttachments()) {
buffer.writeByte(1);
buffer.writeBytes(longToBytes(attachment.readableBytes() + 1));
buffer.writeByte(0xff);
buffer.writeByte(4);
buffer.writeBytes(attachment);
}
}
}
private byte toChar(int number) {
return (byte) (number ^ 0x30);
}
static final char[] DigitTens = {'0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '1', '1', '1', '1',
'1', '1', '1', '1', '1', '1', '2', '2', '2', '2', '2', '2', '2', '2', '2', '2', '3', '3', '3',
'3', '3', '3', '3', '3', '3', '3', '4', '4', '4', '4', '4', '4', '4', '4', '4', '4', '5', '5',
'5', '5', '5', '5', '5', '5', '5', '5', '6', '6', '6', '6', '6', '6', '6', '6', '6', '6', '7',
'7', '7', '7', '7', '7', '7', '7', '7', '7', '8', '8', '8', '8', '8', '8', '8', '8', '8', '8',
'9', '9', '9', '9', '9', '9', '9', '9', '9', '9',};
static final char[] DigitOnes = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3',
'4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2',
'3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1',
'2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0',
'1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',};
static final char[] digits = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e',
'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x',
'y', 'z'};
static final int[] sizeTable = {9, 99, 999, 9999, 99999, 999999, 9999999, 99999999, 999999999,
Integer.MAX_VALUE};
// Requires positive x
static int stringSize(long x) {
for (int i = 0;; i++)
if (x <= sizeTable[i])
return i + 1;
}
static void getChars(long i, int index, byte[] buf) {
long q, r;
int charPos = index;
byte sign = 0;
if (i < 0) {
sign = '-';
i = -i;
}
// Generate two digits per iteration
while (i >= 65536) {
q = i / 100;
// really: r = i - (q * 100);
r = i - ((q << 6) + (q << 5) + (q << 2));
i = q;
buf[--charPos] = (byte) DigitOnes[(int)r];
buf[--charPos] = (byte) DigitTens[(int)r];
}
// Fall thru to fast mode for smaller numbers
// assert(i <= 65536, i);
for (;;) {
q = (i * 52429) >>> (16 + 3);
r = i - ((q << 3) + (q << 1)); // r = i-(q*10) ...
buf[--charPos] = (byte) digits[(int)r];
i = q;
if (i == 0)
break;
}
if (sign != 0) {
buf[--charPos] = sign;
}
}
public static byte[] toChars(long i) {
int size = (i < 0) ? stringSize(-i) + 1 : stringSize(i);
byte[] buf = new byte[size];
getChars(i, size, buf);
return buf;
}
public static byte[] longToBytes(long number) {
// TODO optimize
int length = (int)(Math.log10(number)+1);
byte[] res = new byte[length];
int i = length;
while (number > 0) {
res[--i] = (byte) (number % 10);
number = number / 10;
}
return res;
}
public void encodePacket(Packet packet, ByteBuf buffer, ByteBufAllocator allocator, boolean binary) throws IOException {
ByteBuf buf = buffer;
if (!binary) {
buf = allocateBuffer(allocator);
}
byte type = toChar(packet.getType().getValue());
buf.writeByte(type);
try {
switch (packet.getType()) {
case PONG: {
buf.writeBytes(packet.getData().toString().getBytes(CharsetUtil.UTF_8));
break;
}
case OPEN: {
ByteBufOutputStream out = new ByteBufOutputStream(buf);
jsonSupport.writeValue(out, packet.getData());
break;
}
case MESSAGE: {
ByteBuf encBuf = null;
if (packet.getSubType() == PacketType.ERROR) {
encBuf = allocateBuffer(allocator);
ByteBufOutputStream out = new ByteBufOutputStream(encBuf);
jsonSupport.writeValue(out, packet.getData());
}
if (packet.getSubType() == PacketType.EVENT
|| packet.getSubType() == PacketType.ACK) {
List<Object> values = new ArrayList<Object>();
if (packet.getSubType() == PacketType.EVENT) {
values.add(packet.getName());
}
encBuf = allocateBuffer(allocator);
List<Object> args = packet.getData();
values.addAll(args);
ByteBufOutputStream out = new ByteBufOutputStream(encBuf);
jsonSupport.writeValue(out, values);
if (!jsonSupport.getArrays().isEmpty()) {
packet.initAttachments(jsonSupport.getArrays().size());
for (byte[] array : jsonSupport.getArrays()) {
packet.addAttachment(Unpooled.wrappedBuffer(array));
}
packet.setSubType(PacketType.BINARY_EVENT);
}
}
byte subType = toChar(packet.getSubType().getValue());
buf.writeByte(subType);
if (packet.hasAttachments()) {
byte[] ackId = toChars(packet.getAttachments().size());
buf.writeBytes(ackId);
buf.writeByte('-');
}
if (packet.getSubType() == PacketType.CONNECT) {
if (!packet.getNsp().isEmpty()) {
buf.writeBytes(packet.getNsp().getBytes(CharsetUtil.UTF_8));
}
} else {
if (!packet.getNsp().isEmpty()) {
buf.writeBytes(packet.getNsp().getBytes(CharsetUtil.UTF_8));
buf.writeByte(',');
}
}
if (packet.getAckId() != null) {
byte[] ackId = toChars(packet.getAckId());
buf.writeBytes(ackId);
}
if (encBuf != null) {
buf.writeBytes(encBuf);
encBuf.release();
}
break;
}
}
} finally {
// we need to write a buffer in any case
if (!binary) {
buffer.writeByte(0);
int length = buf.writerIndex();
buffer.writeBytes(longToBytes(length));
buffer.writeByte(0xff);
buffer.writeBytes(buf);
buf.release();
}
}
}
public static int find(ByteBuf buffer, ByteBuf searchValue) {
for (int i = buffer.readerIndex(); i < buffer.readerIndex() + buffer.readableBytes(); i++) {
if (isValueFound(buffer, i, searchValue)) {
return i;
}
}
return -1;
}
private static boolean isValueFound(ByteBuf buffer, int index, ByteBuf search) {
for (int i = 0; i < search.readableBytes(); i++) {
if (buffer.getByte(index + i) != search.getByte(i)) {
return false;
}
}
return true;
}
}