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Breadcrumbs go here --> </ul> </div> <div class="toolbuttons toolblock"> <ul> <li id="smallA" class="t_button">A</li> <li id="medA" class="t_button active">A</li> <li id="bigA" class="t_button">A</li> <li id="print" class="t_button"><a href="javascript:this.print();"> <span>Print</span></a></li> </ul> </div> </div> <div class="content mainContent"> <h1 class="title">ratecontroller.cpp Example File</h1> <span class="small-subtitle">network/torrent/ratecontroller.cpp</span> <!-- $$$network/torrent/ratecontroller.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2015 The Qt Company Ltd. ** Contact: http://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** You may use this file under the terms of the BSD license as follows: ** ** "Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions are ** met: ** * Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** * Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in ** the documentation and/or other materials provided with the ** distribution. ** * Neither the name of The Qt Company Ltd nor the names of its ** contributors may be used to endorse or promote products derived ** from this software without specific prior written permission. ** ** ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="preprocessor">#include "peerwireclient.h"</span> <span class="preprocessor">#include "ratecontroller.h"</span> <span class="preprocessor">#include <QtCore></span> Q_GLOBAL_STATIC(RateController<span class="operator">,</span> rateController) RateController <span class="operator">*</span>RateController<span class="operator">::</span>instance() { <span class="keyword">return</span> rateController(); } <span class="type">void</span> RateController<span class="operator">::</span>addSocket(PeerWireClient <span class="operator">*</span>socket) { connect(socket<span class="operator">,</span> SIGNAL(readyToTransfer())<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(scheduleTransfer())); socket<span class="operator">-</span><span class="operator">></span>setReadBufferSize(downLimit <span class="operator">*</span> <span class="number">4</span>); sockets <span class="operator"><</span><span class="operator"><</span> socket; scheduleTransfer(); } <span class="type">void</span> RateController<span class="operator">::</span>removeSocket(PeerWireClient <span class="operator">*</span>socket) { disconnect(socket<span class="operator">,</span> SIGNAL(readyToTransfer())<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(scheduleTransfer())); socket<span class="operator">-</span><span class="operator">></span>setReadBufferSize(<span class="number">0</span>); sockets<span class="operator">.</span>remove(socket); } <span class="type">void</span> RateController<span class="operator">::</span>setDownloadLimit(<span class="type">int</span> bytesPerSecond) { downLimit <span class="operator">=</span> bytesPerSecond; foreach (PeerWireClient <span class="operator">*</span>socket<span class="operator">,</span> sockets) socket<span class="operator">-</span><span class="operator">></span>setReadBufferSize(downLimit <span class="operator">*</span> <span class="number">4</span>); } <span class="type">void</span> RateController<span class="operator">::</span>scheduleTransfer() { <span class="keyword">if</span> (transferScheduled) <span class="keyword">return</span>; transferScheduled <span class="operator">=</span> <span class="keyword">true</span>; <span class="type"><a href="qtimer.html">QTimer</a></span><span class="operator">::</span>singleShot(<span class="number">50</span><span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(transfer())); } <span class="type">void</span> RateController<span class="operator">::</span>transfer() { transferScheduled <span class="operator">=</span> <span class="keyword">false</span>; <span class="keyword">if</span> (sockets<span class="operator">.</span>isEmpty()) <span class="keyword">return</span>; <span class="type">int</span> msecs <span class="operator">=</span> <span class="number">1000</span>; <span class="keyword">if</span> (<span class="operator">!</span>stopWatch<span class="operator">.</span>isNull()) msecs <span class="operator">=</span> <a href="qtglobal.html#qMin">qMin</a>(msecs<span class="operator">,</span> stopWatch<span class="operator">.</span>elapsed()); <span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span> bytesToWrite <span class="operator">=</span> (upLimit <span class="operator">*</span> msecs) <span class="operator">/</span> <span class="number">1000</span>; <span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span> bytesToRead <span class="operator">=</span> (downLimit <span class="operator">*</span> msecs) <span class="operator">/</span> <span class="number">1000</span>; <span class="keyword">if</span> (bytesToWrite <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span> <span class="operator">&</span><span class="operator">&</span> bytesToRead <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span>) { scheduleTransfer(); <span class="keyword">return</span>; } <span class="type"><a href="qset.html">QSet</a></span><span class="operator"><</span>PeerWireClient <span class="operator">*</span><span class="operator">></span> pendingSockets; foreach (PeerWireClient <span class="operator">*</span>client<span class="operator">,</span> sockets) { <span class="keyword">if</span> (client<span class="operator">-</span><span class="operator">></span>canTransferMore()) pendingSockets <span class="operator"><</span><span class="operator"><</span> client; } <span class="keyword">if</span> (pendingSockets<span class="operator">.</span>isEmpty()) <span class="keyword">return</span>; stopWatch<span class="operator">.</span>start(); <span class="type">bool</span> canTransferMore; <span class="keyword">do</span> { canTransferMore <span class="operator">=</span> <span class="keyword">false</span>; <span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span> writeChunk <span class="operator">=</span> <a href="qtglobal.html#qMax">qMax</a><span class="operator"><</span><span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span><span class="operator">></span>(<span class="number">1</span><span class="operator">,</span> bytesToWrite <span class="operator">/</span> pendingSockets<span class="operator">.</span>size()); <span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span> readChunk <span class="operator">=</span> <a href="qtglobal.html#qMax">qMax</a><span class="operator"><</span><span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span><span class="operator">></span>(<span class="number">1</span><span class="operator">,</span> bytesToRead <span class="operator">/</span> pendingSockets<span class="operator">.</span>size()); <span class="type"><a href="qsetiterator.html">QSetIterator</a></span><span class="operator"><</span>PeerWireClient <span class="operator">*</span><span class="operator">></span> it(pendingSockets); <span class="keyword">while</span> (it<span class="operator">.</span>hasNext() <span class="operator">&</span><span class="operator">&</span> (bytesToWrite <span class="operator">></span> <span class="number">0</span> <span class="operator">|</span><span class="operator">|</span> bytesToRead <span class="operator">></span> <span class="number">0</span>)) { PeerWireClient <span class="operator">*</span>socket <span class="operator">=</span> it<span class="operator">.</span>next(); <span class="keyword">if</span> (socket<span class="operator">-</span><span class="operator">></span>state() <span class="operator">!</span><span class="operator">=</span> <span class="type"><a href="qabstractsocket.html">QAbstractSocket</a></span><span class="operator">::</span>ConnectedState) { pendingSockets<span class="operator">.</span>remove(socket); <span class="keyword">continue</span>; } <span class="type">bool</span> dataTransferred <span class="operator">=</span> <span class="keyword">false</span>; <span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span> available <span class="operator">=</span> <a href="qtglobal.html#qMin">qMin</a><span class="operator"><</span><span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span><span class="operator">></span>(socket<span class="operator">-</span><span class="operator">></span>socketBytesAvailable()<span class="operator">,</span> readChunk); <span class="keyword">if</span> (available <span class="operator">></span> <span class="number">0</span>) { <span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span> readBytes <span class="operator">=</span> socket<span class="operator">-</span><span class="operator">></span>readFromSocket(<a href="qtglobal.html#qMin">qMin</a><span class="operator"><</span><span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span><span class="operator">></span>(available<span class="operator">,</span> bytesToRead)); <span class="keyword">if</span> (readBytes <span class="operator">></span> <span class="number">0</span>) { bytesToRead <span class="operator">-</span><span class="operator">=</span> readBytes; dataTransferred <span class="operator">=</span> <span class="keyword">true</span>; } } <span class="keyword">if</span> (upLimit <span class="operator">*</span> <span class="number">2</span> <span class="operator">></span> socket<span class="operator">-</span><span class="operator">></span>bytesToWrite()) { <span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span> chunkSize <span class="operator">=</span> <a href="qtglobal.html#qMin">qMin</a><span class="operator"><</span><span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span><span class="operator">></span>(writeChunk<span class="operator">,</span> bytesToWrite); <span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span> toWrite <span class="operator">=</span> <a href="qtglobal.html#qMin">qMin</a>(upLimit <span class="operator">*</span> <span class="number">2</span> <span class="operator">-</span> socket<span class="operator">-</span><span class="operator">></span>bytesToWrite()<span class="operator">,</span> chunkSize); <span class="keyword">if</span> (toWrite <span class="operator">></span> <span class="number">0</span>) { <span class="type"><a href="qtglobal.html#qint64-typedef">qint64</a></span> writtenBytes <span class="operator">=</span> socket<span class="operator">-</span><span class="operator">></span>writeToSocket(toWrite); <span class="keyword">if</span> (writtenBytes <span class="operator">></span> <span class="number">0</span>) { bytesToWrite <span class="operator">-</span><span class="operator">=</span> writtenBytes; dataTransferred <span class="operator">=</span> <span class="keyword">true</span>; } } } <span class="keyword">if</span> (dataTransferred <span class="operator">&</span><span class="operator">&</span> socket<span class="operator">-</span><span class="operator">></span>canTransferMore()) canTransferMore <span class="operator">=</span> <span class="keyword">true</span>; <span class="keyword">else</span> pendingSockets<span class="operator">.</span>remove(socket); } } <span class="keyword">while</span> (canTransferMore <span class="operator">&</span><span class="operator">&</span> (bytesToWrite <span class="operator">></span> <span class="number">0</span> <span class="operator">|</span><span class="operator">|</span> bytesToRead <span class="operator">></span> <span class="number">0</span>) <span class="operator">&</span><span class="operator">&</span> <span class="operator">!</span>pendingSockets<span class="operator">.</span>isEmpty()); <span class="keyword">if</span> (canTransferMore <span class="operator">|</span><span class="operator">|</span> bytesToWrite <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span> <span class="operator">|</span><span class="operator">|</span> bytesToRead <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span>) scheduleTransfer(); }</pre> </div> <!-- @@@network/torrent/ratecontroller.cpp --> </div> </div> </div> <div class="ft"> <span></span> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2015 The Qt Company Ltd. 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