<?xml version="1.0" encoding="iso-8859-1"?>
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<title>Qt 4.3: peerwireclient.cpp Example File (network/torrent/peerwireclient.cpp)</title>
<link href="classic.css" rel="stylesheet" type="text/css" />
</head>
<body>
<table border="0" cellpadding="0" cellspacing="0" width="100%">
<tr>
<td align="left" valign="top" width="32"><a href="http://www.trolltech.com/products/qt"><img src="images/qt-logo.png" align="left" width="32" height="32" border="0" /></a></td>
<td width="1"> </td><td class="postheader" valign="center"><a href="index.html"><font color="#004faf">Home</font></a> · <a href="classes.html"><font color="#004faf">All Classes</font></a> · <a href="mainclasses.html"><font color="#004faf">Main Classes</font></a> · <a href="groups.html"><font color="#004faf">Grouped Classes</font></a> · <a href="modules.html"><font color="#004faf">Modules</font></a> · <a href="functions.html"><font color="#004faf">Functions</font></a></td>
<td align="right" valign="top" width="230"><a href="http://www.trolltech.com"><img src="images/trolltech-logo.png" align="right" width="203" height="32" border="0" /></a></td></tr></table><h1 align="center">peerwireclient.cpp Example File<br /><sup><sup>network/torrent/peerwireclient.cpp</sup></sup></h1>
<pre><span class="comment"> /****************************************************************************
**
** Copyright (C) 2004-2008 Trolltech ASA. All rights reserved.
**
** This file is part of the example classes of the Qt Toolkit.
**
** This file may be used under the terms of the GNU General Public
** License versions 2.0 or 3.0 as published by the Free Software
** Foundation and appearing in the files LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Alternatively you may (at
** your option) use any later version of the GNU General Public
** License if such license has been publicly approved by Trolltech ASA
** (or its successors, if any) and the KDE Free Qt Foundation. In
** addition, as a special exception, Trolltech gives you certain
** additional rights. These rights are described in the Trolltech GPL
** Exception version 1.1, which can be found at
** http://www.trolltech.com/products/qt/gplexception/ and in the file
** GPL_EXCEPTION.txt in this package.
**
** Please review the following information to ensure GNU General
** Public Licensing requirements will be met:
** http://trolltech.com/products/qt/licenses/licensing/opensource/. If
** you are unsure which license is appropriate for your use, please
** review the following information:
** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
** or contact the sales department at sales@trolltech.com.
**
** In addition, as a special exception, Trolltech, as the sole
** copyright holder for Qt Designer, grants users of the Qt/Eclipse
** Integration plug-in the right for the Qt/Eclipse Integration to
** link to functionality provided by Qt Designer and its related
** libraries.
**
** This file is provided "AS IS" with NO WARRANTY OF ANY KIND,
** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE. Trolltech reserves all rights not expressly
** granted herein.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
****************************************************************************/</span>
#include "peerwireclient.h"
#include <QHostAddress>
#include <QTimerEvent>
static const int PendingRequestTimeout = 60 * 1000;
static const int ClientTimeout = 120 * 1000;
static const int ConnectTimeout = 60 * 1000;
static const int KeepAliveInterval = 30 * 1000;
static const int RateControlTimerDelay = 2000;
static const int MinimalHeaderSize = 48;
static const int FullHeaderSize = 68;
static const char ProtocolId[] = "BitTorrent protocol";
static const char ProtocolIdSize = 19;
<span class="comment"> //</span> Reads a 32bit unsigned int from data in network order.
static inline quint32 fromNetworkData(const char *data)
{
const unsigned char *udata = (const unsigned char *)data;
return (quint32(udata[0]) << 24)
| (quint32(udata[1]) << 16)
| (quint32(udata[2]) << 8)
| (quint32(udata[3]));
}
<span class="comment"> //</span> Writes a 32bit unsigned int from num to data in network order.
static inline void toNetworkData(quint32 num, char *data)
{
unsigned char *udata = (unsigned char *)data;
udata[3] = (num & 0xff);
udata[2] = (num & 0xff00) >> 8;
udata[1] = (num & 0xff0000) >> 16;
udata[0] = (num & 0xff000000) >> 24;
}
<span class="comment"> //</span> Constructs an unconnected PeerWire client and starts the connect timer.
PeerWireClient::PeerWireClient(const QByteArray &peerId, QObject *parent)
: QTcpSocket(parent), pendingBlockSizes(0),
pwState(ChokingPeer | ChokedByPeer), receivedHandShake(false), gotPeerId(false),
sentHandShake(false), nextPacketLength(-1), pendingRequestTimer(0), invalidateTimeout(false),
keepAliveTimer(0), torrentPeer(0)
{
memset(uploadSpeedData, 0, sizeof(uploadSpeedData));
memset(downloadSpeedData, 0, sizeof(downloadSpeedData));
transferSpeedTimer = startTimer(RateControlTimerDelay);
timeoutTimer = startTimer(ConnectTimeout);
peerIdString = peerId;
connect(this, SIGNAL(readyRead()), this, SIGNAL(readyToTransfer()));
connect(this, SIGNAL(connected()), this, SIGNAL(readyToTransfer()));
connect(&socket, SIGNAL(connected()),
this, SIGNAL(connected()));
connect(&socket, SIGNAL(readyRead()),
this, SIGNAL(readyRead()));
connect(&socket, SIGNAL(disconnected()),
this, SIGNAL(disconnected()));
connect(&socket, SIGNAL(error(QAbstractSocket::SocketError)),
this, SIGNAL(error(QAbstractSocket::SocketError)));
connect(&socket, SIGNAL(bytesWritten(qint64)),
this, SIGNAL(bytesWritten(qint64)));
connect(&socket, SIGNAL(stateChanged(QAbstractSocket::SocketState)),
this, SLOT(socketStateChanged(QAbstractSocket::SocketState)));
}
<span class="comment"> //</span> Registers the peer ID and SHA1 sum of the torrent, and initiates
<span class="comment"> //</span> the handshake.
void PeerWireClient::initialize(const QByteArray &infoHash, int pieceCount)
{
this->infoHash = infoHash;
peerPieces.resize(pieceCount);
if (!sentHandShake)
sendHandShake();
}
void PeerWireClient::setPeer(TorrentPeer *peer)
{
torrentPeer = peer;
}
TorrentPeer *PeerWireClient::peer() const
{
return torrentPeer;
}
QBitArray PeerWireClient::availablePieces() const
{
return peerPieces;
}
QList<TorrentBlock> PeerWireClient::incomingBlocks() const
{
return incoming;
}
<span class="comment"> //</span> Sends a "choke" message, asking the peer to stop requesting blocks.
void PeerWireClient::chokePeer()
{
const char message[] = {0, 0, 0, 1, 0};
write(message, sizeof(message));
pwState |= ChokingPeer;
<span class="comment">//</span> After receiving a choke message, the peer will assume all
<span class="comment">//</span> pending requests are lost.
pendingBlocks.clear();
pendingBlockSizes = 0;
}
<span class="comment"> //</span> Sends an "unchoke" message, allowing the peer to start/resume
<span class="comment"> //</span> requesting blocks.
void PeerWireClient::unchokePeer()
{
const char message[] = {0, 0, 0, 1, 1};
write(message, sizeof(message));
pwState &= ~ChokingPeer;
if (pendingRequestTimer)
killTimer(pendingRequestTimer);
}
<span class="comment"> //</span> Sends a "keep-alive" message to prevent the peer from closing
<span class="comment"> //</span> the connection when there's no activity
void PeerWireClient::sendKeepAlive()
{
const char message[] = {0, 0, 0, 0};
write(message, sizeof(message));
}
<span class="comment"> //</span> Sends an "interested" message, informing the peer that it has got
<span class="comment"> //</span> pieces that we'd like to download.
void PeerWireClient::sendInterested()
{
const char message[] = {0, 0, 0, 1, 2};
write(message, sizeof(message));
pwState |= InterestedInPeer;
<span class="comment">//</span> After telling the peer that we're interested, we expect to get
<span class="comment">//</span> unchoked within a certain timeframe; otherwise we'll drop the
<span class="comment">//</span> connection.
if (pendingRequestTimer)
killTimer(pendingRequestTimer);
pendingRequestTimer = startTimer(PendingRequestTimeout);
}
<span class="comment"> //</span> Sends a "not interested" message, informing the peer that it does
<span class="comment"> //</span> not have any pieces that we'd like to download.
void PeerWireClient::sendNotInterested()
{
const char message[] = {0, 0, 0, 1, 3};
write(message, sizeof(message));
pwState &= ~InterestedInPeer;
}
<span class="comment"> //</span> Sends a piece notification / a "have" message, informing the peer
<span class="comment"> //</span> that we have just downloaded a new piece.
void PeerWireClient::sendPieceNotification(int piece)
{
if (!sentHandShake)
sendHandShake();
char message[] = {0, 0, 0, 5, 4, 0, 0, 0, 0};
toNetworkData(piece, &message[5]);
write(message, sizeof(message));
}
<span class="comment"> //</span> Sends the complete list of pieces that we have downloaded.
void PeerWireClient::sendPieceList(const QBitArray &bitField)
{
<span class="comment">//</span> The bitfield message may only be sent immediately after the
<span class="comment">//</span> handshaking sequence is completed, and before any other
<span class="comment">//</span> messages are sent.
if (!sentHandShake)
sendHandShake();
<span class="comment">//</span> Don't send the bitfield if it's all zeros.
if (bitField.count(true) == 0)
return;
int bitFieldSize = bitField.size();
int size = (bitFieldSize + 7) / 8;
QByteArray bits(size, '\0');
for (int i = 0; i < bitFieldSize; ++i) {
if (bitField.testBit(i)) {
quint32 byte = quint32(i) / 8;
quint32 bit = quint32(i) % 8;
bits[byte] = uchar(bits.at(byte)) | (1 << (7 - bit));
}
}
char message[] = {0, 0, 0, 1, 5};
toNetworkData(bits.size() + 1, &message[0]);
write(message, sizeof(message));
write(bits);
}
<span class="comment"> //</span> Sends a request for a block.
void PeerWireClient::requestBlock(int piece, int offset, int length)
{
char message[] = {0, 0, 0, 1, 6};
toNetworkData(13, &message[0]);
write(message, sizeof(message));
char numbers[4 * 3];
toNetworkData(piece, &numbers[0]);
toNetworkData(offset, &numbers[4]);
toNetworkData(length, &numbers[8]);
write(numbers, sizeof(numbers));
incoming << TorrentBlock(piece, offset, length);
<span class="comment">//</span> After requesting a block, we expect the block to be sent by the
<span class="comment">//</span> other peer within a certain number of seconds. Otherwise, we
<span class="comment">//</span> drop the connection.
if (pendingRequestTimer)
killTimer(pendingRequestTimer);
pendingRequestTimer = startTimer(PendingRequestTimeout);
}
<span class="comment"> //</span> Cancels a request for a block.
void PeerWireClient::cancelRequest(int piece, int offset, int length)
{
char message[] = {0, 0, 0, 1, 8};
toNetworkData(13, &message[0]);
write(message, sizeof(message));
char numbers[4 * 3];
toNetworkData(piece, &numbers[0]);
toNetworkData(offset, &numbers[4]);
toNetworkData(length, &numbers[8]);
write(numbers, sizeof(numbers));
incoming.removeAll(TorrentBlock(piece, offset, length));
}
<span class="comment"> //</span> Sends a block to the peer.
void PeerWireClient::sendBlock(int piece, int offset, const QByteArray &data)
{
QByteArray block;
char message[] = {0, 0, 0, 1, 7};
toNetworkData(9 + data.size(), &message[0]);
block += QByteArray(message, sizeof(message));
char numbers[4 * 2];
toNetworkData(piece, &numbers[0]);
toNetworkData(offset, &numbers[4]);
block += QByteArray(numbers, sizeof(numbers));
block += data;
BlockInfo blockInfo;
blockInfo.pieceIndex = piece;
blockInfo.offset = offset;
blockInfo.length = data.size();
blockInfo.block = block;
pendingBlocks << blockInfo;
pendingBlockSizes += block.size();
if (pendingBlockSizes > 32 * 16384) {
chokePeer();
unchokePeer();
return;
}
emit readyToTransfer();
}
<span class="comment"> //</span> Attempts to write 'bytes' bytes to the socket from the buffer.
<span class="comment"> //</span> This is used by RateController, which precisely controls how much
<span class="comment"> //</span> each client can write.
qint64 PeerWireClient::writeToSocket(qint64 bytes)
{
qint64 totalWritten = 0;
do {
if (outgoingBuffer.isEmpty() && !pendingBlocks.isEmpty()) {
BlockInfo block = pendingBlocks.takeFirst();
pendingBlockSizes -= block.length;
outgoingBuffer += block.block;
}
qint64 written = socket.write(outgoingBuffer.constData(),
qMin<qint64>(bytes - totalWritten, outgoingBuffer.size()));
if (written <= 0)
return totalWritten ? totalWritten : written;
totalWritten += written;
uploadSpeedData[0] += written;
outgoingBuffer.remove(0, written);
} while (totalWritten < bytes && (!outgoingBuffer.isEmpty() || !pendingBlocks.isEmpty()));
return totalWritten;
}
<span class="comment"> //</span> Attempts to read at most 'bytes' bytes from the socket.
qint64 PeerWireClient::readFromSocket(qint64 bytes)
{
char buffer[1024];
qint64 totalRead = 0;
do {
qint64 bytesRead = socket.read(buffer, qMin<qint64>(sizeof(buffer), bytes - totalRead));
if (bytesRead <= 0)
break;
qint64 oldSize = incomingBuffer.size();
incomingBuffer.resize(oldSize + bytesRead);
memcpy(incomingBuffer.data() + oldSize, buffer, bytesRead);
totalRead += bytesRead;
} while (totalRead < bytes);
if (totalRead > 0) {
downloadSpeedData[0] += totalRead;
emit bytesReceived(totalRead);
processIncomingData();
}
return totalRead;
}
<span class="comment"> //</span> Returns the average number of bytes per second this client is
<span class="comment"> //</span> downloading.
qint64 PeerWireClient::downloadSpeed() const
{
qint64 sum = 0;
for (unsigned int i = 0; i < sizeof(downloadSpeedData) / sizeof(qint64); ++i)
sum += downloadSpeedData[i];
return sum / (8 * 2);
}
<span class="comment"> //</span> Returns the average number of bytes per second this client is
<span class="comment"> //</span> uploading.
qint64 PeerWireClient::uploadSpeed() const
{
qint64 sum = 0;
for (unsigned int i = 0; i < sizeof(uploadSpeedData) / sizeof(qint64); ++i)
sum += uploadSpeedData[i];
return sum / (8 * 2);
}
void PeerWireClient::setReadBufferSize(int size)
{
socket.setReadBufferSize(size);
}
bool PeerWireClient::canTransferMore() const
{
return bytesAvailable() > 0 || socket.bytesAvailable() > 0
|| !outgoingBuffer.isEmpty() || !pendingBlocks.isEmpty();
}
void PeerWireClient::connectToHostImplementation(const QString &hostName,
quint16 port, OpenMode openMode)
{
setOpenMode(openMode);
socket.connectToHost(hostName, port, openMode);
}
void PeerWireClient::diconnectFromHostImplementation()
{
socket.disconnectFromHost();
}
void PeerWireClient::timerEvent(QTimerEvent *event)
{
if (event->timerId() == transferSpeedTimer) {
<span class="comment">//</span> Rotate the upload / download records.
for (int i = 6; i >= 0; --i) {
uploadSpeedData[i + 1] = uploadSpeedData[i];
downloadSpeedData[i + 1] = downloadSpeedData[i];
}
uploadSpeedData[0] = 0;
downloadSpeedData[0] = 0;
} else if (event->timerId() == timeoutTimer) {
<span class="comment">//</span> Disconnect if we timed out; otherwise the timeout is
<span class="comment">//</span> restarted.
if (invalidateTimeout) {
invalidateTimeout = false;
} else {
abort();
}
} else if (event->timerId() == pendingRequestTimer) {
abort();
} else if (event->timerId() == keepAliveTimer) {
sendKeepAlive();
}
QTcpSocket::timerEvent(event);
}
<span class="comment"> //</span> Sends the handshake to the peer.
void PeerWireClient::sendHandShake()
{
sentHandShake = true;
<span class="comment">//</span> Restart the timeout
if (timeoutTimer)
killTimer(timeoutTimer);
timeoutTimer = startTimer(ClientTimeout);
<span class="comment">//</span> Write the 68 byte PeerWire handshake.
write(&ProtocolIdSize, 1);
write(ProtocolId, ProtocolIdSize);
write(QByteArray(8, '\0'));
write(infoHash);
write(peerIdString);
}
void PeerWireClient::processIncomingData()
{
invalidateTimeout = true;
if (!receivedHandShake) {
<span class="comment">//</span> Check that we received enough data
if (bytesAvailable() < MinimalHeaderSize)
return;
<span class="comment">//</span> Sanity check the protocol ID
QByteArray id = read(ProtocolIdSize + 1);
if (id.at(0) != ProtocolIdSize || !id.mid(1).startsWith(ProtocolId)) {
abort();
return;
}
<span class="comment">//</span> Discard 8 reserved bytes, then read the info hash and peer ID
(void) read(8);
<span class="comment">//</span> Read infoHash
QByteArray peerInfoHash = read(20);
if (!infoHash.isEmpty() && peerInfoHash != infoHash) {
abort();
return;
}
emit infoHashReceived(peerInfoHash);
if (infoHash.isEmpty()) {
abort();
return;
}
<span class="comment">//</span> Send handshake
if (!sentHandShake)
sendHandShake();
receivedHandShake = true;
}
<span class="comment">//</span> Handle delayed peer id arrival
if (!gotPeerId) {
if (bytesAvailable() < 20)
return;
gotPeerId = true;
if (read(20) == peerIdString) {
<span class="comment">//</span> We connected to ourself
abort();
return;
}
}
<span class="comment">//</span> Initialize keep-alive timer
if (!keepAliveTimer)
keepAliveTimer = startTimer(KeepAliveInterval);
do {
<span class="comment">//</span> Find the packet length
if (nextPacketLength == -1) {
if (bytesAvailable() < 4)
return;
char tmp[4];
read(tmp, sizeof(tmp));
nextPacketLength = fromNetworkData(tmp);
if (nextPacketLength < 0 || nextPacketLength > 200000) {
<span class="comment">//</span> Prevent DoS
abort();
return;
}
}
<span class="comment">//</span> KeepAlive
if (nextPacketLength == 0) {
nextPacketLength = -1;
continue;
}
<span class="comment">//</span> Wait with parsing until the whole packet has been received
if (bytesAvailable() < nextPacketLength)
return;
<span class="comment">//</span> Read the packet
QByteArray packet = read(nextPacketLength);
if (packet.size() != nextPacketLength) {
abort();
return;
}
switch (packet.at(0)) {
case ChokePacket:
<span class="comment">//</span> We have been choked.
pwState |= ChokedByPeer;
incoming.clear();
if (pendingRequestTimer)
killTimer(pendingRequestTimer);
emit choked();
break;
case UnchokePacket:
<span class="comment">//</span> We have been unchoked.
pwState &= ~ChokedByPeer;
emit unchoked();
break;
case InterestedPacket:
<span class="comment">//</span> The peer is interested in downloading.
pwState |= PeerIsInterested;
emit interested();
break;
case NotInterestedPacket:
<span class="comment">//</span> The peer is not interested in downloading.
pwState &= ~PeerIsInterested;
emit notInterested();
break;
case HavePacket: {
<span class="comment">//</span> The peer has a new piece available.
quint32 index = fromNetworkData(&packet.data()[1]);
if (index < quint32(peerPieces.size())) {
<span class="comment">//</span> Only accept indexes within the valid range.
peerPieces.setBit(int(index));
}
emit piecesAvailable(availablePieces());
break;
}
case BitFieldPacket:
<span class="comment">//</span> The peer has the following pieces available.
for (int i = 1; i < packet.size(); ++i) {
for (int bit = 0; bit < 8; ++bit) {
if (packet.at(i) & (1 << (7 - bit))) {
int bitIndex = int(((i - 1) * 8) + bit);
if (bitIndex >= 0 && bitIndex < peerPieces.size()) {
<span class="comment">//</span> Occasionally, broken clients claim to have
<span class="comment">//</span> pieces whose index is outside the valid range.
<span class="comment">//</span> The most common mistake is the index == size
<span class="comment">//</span> case.
peerPieces.setBit(bitIndex);
}
}
}
}
emit piecesAvailable(availablePieces());
break;
case RequestPacket: {
<span class="comment">//</span> The peer requests a block.
quint32 index = fromNetworkData(&packet.data()[1]);
quint32 begin = fromNetworkData(&packet.data()[5]);
quint32 length = fromNetworkData(&packet.data()[9]);
emit blockRequested(int(index), int(begin), int(length));
break;
}
case PiecePacket: {
int index = int(fromNetworkData(&packet.data()[1]));
int begin = int(fromNetworkData(&packet.data()[5]));
incoming.removeAll(TorrentBlock(index, begin, packet.size() - 9));
<span class="comment">//</span> The peer sends a block.
emit blockReceived(index, begin, packet.mid(9));
<span class="comment">//</span> Kill the pending block timer.
if (pendingRequestTimer) {
killTimer(pendingRequestTimer);
pendingRequestTimer = 0;
}
break;
}
case CancelPacket: {
<span class="comment">//</span> The peer cancels a block request.
quint32 index = fromNetworkData(&packet.data()[1]);
quint32 begin = fromNetworkData(&packet.data()[5]);
quint32 length = fromNetworkData(&packet.data()[9]);
for (int i = 0; i < pendingBlocks.size(); ++i) {
const BlockInfo &blockInfo = pendingBlocks.at(i);
if (blockInfo.pieceIndex == int(index)
&& blockInfo.offset == int(begin)
&& blockInfo.length == int(length)) {
pendingBlocks.removeAt(i);
break;
}
}
break;
}
default:
<span class="comment">//</span> Unsupported packet type; just ignore it.
break;
}
nextPacketLength = -1;
} while (bytesAvailable() > 0);
}
void PeerWireClient::socketStateChanged(QAbstractSocket::SocketState state)
{
setLocalAddress(socket.localAddress());
setLocalPort(socket.localPort());
setPeerName(socket.peerName());
setPeerAddress(socket.peerAddress());
setPeerPort(socket.peerPort());
setSocketState(state);
}
qint64 PeerWireClient::readData(char *data, qint64 size)
{
int n = qMin<int>(size, incomingBuffer.size());
memcpy(data, incomingBuffer.constData(), n);
incomingBuffer.remove(0, n);
return n;
}
qint64 PeerWireClient::readLineData(char *data, qint64 maxlen)
{
return QIODevice::readLineData(data, maxlen);
}
qint64 PeerWireClient::writeData(const char *data, qint64 size)
{
int oldSize = outgoingBuffer.size();
outgoingBuffer.resize(oldSize + size);
memcpy(outgoingBuffer.data() + oldSize, data, size);
emit readyToTransfer();
return size;
}</pre>
<p /><address><hr /><div align="center">
<table width="100%" cellspacing="0" border="0"><tr class="address">
<td width="30%">Copyright © 2008 <a href="trolltech.html">Trolltech</a></td>
<td width="40%" align="center"><a href="trademarks.html">Trademarks</a></td>
<td width="30%" align="right"><div align="right">Qt 4.3.4</div></td>
</tr></table></div></address></body>
</html>
distrib
>
Mandriva
>
2008.1
>
x86_64
>
media
>
main-release
>
by-pkgid
>
c5a68a1bfbb41dd7ab32131d8bbca747
>
files
>
1669
