AirTV-Qt/qtsingleapplication/src/qtlocalpeer.cpp

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  39
  40
  41 #include "qtlocalpeer.h"
  42 #include <QtCore/QCoreApplication>
  43 #include <QtCore/QTime>
  44
  45 #if defined(Q_OS_WIN)
  46 #include <QtCore/QLibrary>
  47 #include <QtCore/qt_windows.h>
  48 typedef BOOL(WINAPI*PProcessIdToSessionId)(DWORD,DWORD*);
  49 static PProcessIdToSessionId pProcessIdToSessionId = 0;
  50 #endif
  51 #if defined(Q_OS_UNIX)
  52 #include <time.h>
  53 #endif
  54
  55 namespace QtLP_Private {
  56 #include "qtlockedfile.cpp"
  57 #if defined(Q_OS_WIN)
  58 #include "qtlockedfile_win.cpp"
  59 #else
  60 #include "qtlockedfile_unix.cpp"
  61 #endif
  62 }
  63
  64 const char* QtLocalPeer::ack = "ack";
  65
  66 QtLocalPeer::QtLocalPeer(QObject* parent, const QString &appId)
  67     : QObject(parent), id(appId)
  68 {
  69     QString prefix = id;
  70     if (id.isEmpty()) {
  71         id = QCoreApplication::applicationFilePath();
  72 #if defined(Q_OS_WIN)
  73         id = id.toLower();
  74 #endif
  75         prefix = id.section(QLatin1Char('/'), -1);
  76     }
  77     prefix.remove(QRegExp("[^a-zA-Z]"));
  78     prefix.truncate(6);
  79
  80     QByteArray idc = id.toUtf8();
  81     quint16 idNum = qChecksum(idc.constData(), idc.size());
  82     socketName = QLatin1String("qtsingleapp-") + prefix
  83                  + QLatin1Char('-') + QString::number(idNum, 16);
  84
  85 #if defined(Q_OS_WIN)
  86     if (!pProcessIdToSessionId) {
  87         QLibrary lib("kernel32");
  88         pProcessIdToSessionId = (PProcessIdToSessionId)lib.resolve("ProcessIdToSessionId");
  89     }
  90     if (pProcessIdToSessionId) {
  91         DWORD sessionId = 0;
  92         pProcessIdToSessionId(GetCurrentProcessId(), &sessionId);
  93         socketName += QLatin1Char('-') + QString::number(sessionId, 16);
  94     }
  95 #else
  96     socketName += QLatin1Char('-') + QString::number(::getuid(), 16);
  97 #endif
  98
  99     server = new QLocalServer(this);
 100     QString lockName = QDir(QDir::tempPath()).absolutePath()
 101                        + QLatin1Char('/') + socketName
 102                        + QLatin1String("-lockfile");
 103     lockFile.setFileName(lockName);
 104     lockFile.open(QIODevice::ReadWrite);
 105 }
 106
 107
 108
 109 bool QtLocalPeer::isClient()
 110 {
 111     if (lockFile.isLocked())
 112         return false;
 113
 114     if (!lockFile.lock(QtLP_Private::QtLockedFile::WriteLock, false))
 115         return true;
 116
 117     bool res = server->listen(socketName);
 118 #if defined(Q_OS_UNIX) && (QT_VERSION >= QT_VERSION_CHECK(4,5,0))
 119     // ### Workaround
 120     if (!res && server->serverError() == QAbstractSocket::AddressInUseError) {
 121         QFile::remove(QDir::cleanPath(QDir::tempPath())+QLatin1Char('/')+socketName);
 122         res = server->listen(socketName);
 123     }
 124 #endif
 125     if (!res)
 126         qWarning("QtSingleCoreApplication: listen on local socket failed, %s", qPrintable(server->errorString()));
 127     QObject::connect(server, SIGNAL(newConnection()), SLOT(receiveConnection()));
 128     return false;
 129 }
 130
 131
 132 bool QtLocalPeer::sendMessage(const QString &message, int timeout)
 133 {
 134     if (!isClient())
 135         return false;
 136
 137     QLocalSocket socket;
 138     bool connOk = false;
 139     for(int i = 0; i < 2; i++) {
 140         // Try twice, in case the other instance is just starting up
 141         socket.connectToServer(socketName);
 142         connOk = socket.waitForConnected(timeout/2);
 143         if (connOk || i)
 144             break;
 145         int ms = 250;
 146 #if defined(Q_OS_WIN)
 147         Sleep(DWORD(ms));
 148 #else
 149         struct timespec ts = { ms / 1000, (ms % 1000) * 1000 * 1000 };
 150         nanosleep(&ts, NULL);
 151 #endif
 152     }
 153     if (!connOk)
 154         return false;
 155
 156     QByteArray uMsg(message.toUtf8());
 157     QDataStream ds(&socket);
 158     ds.writeBytes(uMsg.constData(), uMsg.size());
 159     bool res = socket.waitForBytesWritten(timeout);
 160     if (res) {
 161         res &= socket.waitForReadyRead(timeout);   // wait for ack
 162         if (res)
 163             res &= (socket.read(qstrlen(ack)) == ack);
 164     }
 165     return res;
 166 }
 167
 168
 169 void QtLocalPeer::receiveConnection()
 170 {
 171     QLocalSocket* socket = server->nextPendingConnection();
 172     if (!socket)
 173         return;
 174
 175     while (socket->bytesAvailable() < (int)sizeof(quint32))
 176         socket->waitForReadyRead();
 177     QDataStream ds(socket);
 178     QByteArray uMsg;
 179     quint32 remaining;
 180     ds >> remaining;
 181     uMsg.resize(remaining);
 182     int got = 0;
 183     char* uMsgBuf = uMsg.data();
 184     do {
 185         got = ds.readRawData(uMsgBuf, remaining);
 186         remaining -= got;
 187         uMsgBuf += got;
 188     } while (remaining && got >= 0 && socket->waitForReadyRead(2000));
 189     if (got < 0) {
 190         qWarning("QtLocalPeer: Message reception failed %s", socket->errorString().toLatin1().constData());
 191         delete socket;
 192         return;
 193     }
 194     QString message(QString::fromUtf8(uMsg));
 195     socket->write(ack, qstrlen(ack));
 196     socket->waitForBytesWritten(1000);
 197     delete socket;
 198     emit messageReceived(message); //### (might take a long time to return)
 199 }