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 #include <unistd.h>
  45
  46 #if defined(Q_OS_WIN)
  47 #include <QtCore/QLibrary>
  48 #include <QtCore/qt_windows.h>
  49 typedef BOOL(WINAPI*PProcessIdToSessionId)(DWORD,DWORD*);
  50 static PProcessIdToSessionId pProcessIdToSessionId = 0;
  51 #endif
  52 #if defined(Q_OS_UNIX)
  53 #include <time.h>
  54 #endif
  55
  56 namespace QtLP_Private {
  57 #include "qtlockedfile.cpp"
  58 #if defined(Q_OS_WIN)
  59 #include "qtlockedfile_win.cpp"
  60 #else
  61 #include "qtlockedfile_unix.cpp"
  62 #endif
  63 }
  64
  65 const char* QtLocalPeer::ack = "ack";
  66
  67 QtLocalPeer::QtLocalPeer(QObject* parent, const QString &appId)
  68     : QObject(parent), id(appId)
  69 {
  70     QString prefix = id;
  71     if (id.isEmpty()) {
  72         id = QCoreApplication::applicationFilePath();
  73 #if defined(Q_OS_WIN)
  74         id = id.toLower();
  75 #endif
  76         prefix = id.section(QLatin1Char('/'), -1);
  77     }
  78     prefix.remove(QRegExp("[^a-zA-Z]"));
  79     prefix.truncate(6);
  80
  81     QByteArray idc = id.toUtf8();
  82     quint16 idNum = qChecksum(idc.constData(), idc.size());
  83     socketName = QLatin1String("qtsingleapp-") + prefix
  84                  + QLatin1Char('-') + QString::number(idNum, 16);
  85
  86 #if defined(Q_OS_WIN)
  87     if (!pProcessIdToSessionId) {
  88         QLibrary lib("kernel32");
  89         pProcessIdToSessionId = (PProcessIdToSessionId)lib.resolve("ProcessIdToSessionId");
  90     }
  91     if (pProcessIdToSessionId) {
  92         DWORD sessionId = 0;
  93         pProcessIdToSessionId(GetCurrentProcessId(), &sessionId);
  94         socketName += QLatin1Char('-') + QString::number(sessionId, 16);
  95     }
  96 #else
  97     socketName += QLatin1Char('-') + QString::number(::getuid(), 16);
  98 #endif
  99
 100     server = new QLocalServer(this);
 101     QString lockName = QDir(QDir::tempPath()).absolutePath()
 102                        + QLatin1Char('/') + socketName
 103                        + QLatin1String("-lockfile");
 104     lockFile.setFileName(lockName);
 105     lockFile.open(QIODevice::ReadWrite);
 106 }
 107
 108
 109
 110 bool QtLocalPeer::isClient()
 111 {
 112     if (lockFile.isLocked())
 113         return false;
 114
 115     if (!lockFile.lock(QtLP_Private::QtLockedFile::WriteLock, false))
 116         return true;
 117
 118     bool res = server->listen(socketName);
 119 #if defined(Q_OS_UNIX) && (QT_VERSION >= QT_VERSION_CHECK(4,5,0))
 120     // ### Workaround
 121     if (!res && server->serverError() == QAbstractSocket::AddressInUseError) {
 122         QFile::remove(QDir::cleanPath(QDir::tempPath())+QLatin1Char('/')+socketName);
 123         res = server->listen(socketName);
 124     }
 125 #endif
 126     if (!res)
 127         qWarning("QtSingleCoreApplication: listen on local socket failed, %s", qPrintable(server->errorString()));
 128     QObject::connect(server, SIGNAL(newConnection()), SLOT(receiveConnection()));
 129     return false;
 130 }
 131
 132
 133 bool QtLocalPeer::sendMessage(const QString &message, int timeout)
 134 {
 135     if (!isClient())
 136         return false;
 137
 138     QLocalSocket socket;
 139     bool connOk = false;
 140     for(int i = 0; i < 2; i++) {
 141         // Try twice, in case the other instance is just starting up
 142         socket.connectToServer(socketName);
 143         connOk = socket.waitForConnected(timeout/2);
 144         if (connOk || i)
 145             break;
 146         int ms = 250;
 147 #if defined(Q_OS_WIN)
 148         Sleep(DWORD(ms));
 149 #else
 150         struct timespec ts = { ms / 1000, (ms % 1000) * 1000 * 1000 };
 151         nanosleep(&ts, NULL);
 152 #endif
 153     }
 154     if (!connOk)
 155         return false;
 156
 157     QByteArray uMsg(message.toUtf8());
 158     QDataStream ds(&socket);
 159     ds.writeBytes(uMsg.constData(), uMsg.size());
 160     bool res = socket.waitForBytesWritten(timeout);
 161     if (res) {
 162         res &= socket.waitForReadyRead(timeout);   // wait for ack
 163         if (res)
 164             res &= (socket.read(qstrlen(ack)) == ack);
 165     }
 166     return res;
 167 }
 168
 169
 170 void QtLocalPeer::receiveConnection()
 171 {
 172     QLocalSocket* socket = server->nextPendingConnection();
 173     if (!socket)
 174         return;
 175
 176     while (socket->bytesAvailable() < (int)sizeof(quint32))
 177         socket->waitForReadyRead();
 178     QDataStream ds(socket);
 179     QByteArray uMsg;
 180     quint32 remaining;
 181     ds >> remaining;
 182     uMsg.resize(remaining);
 183     int got = 0;
 184     char* uMsgBuf = uMsg.data();
 185     do {
 186         got = ds.readRawData(uMsgBuf, remaining);
 187         remaining -= got;
 188         uMsgBuf += got;
 189     } while (remaining && got >= 0 && socket->waitForReadyRead(2000));
 190     if (got < 0) {
 191         qWarning("QtLocalPeer: Message reception failed %s", socket->errorString().toLatin1().constData());
 192         delete socket;
 193         return;
 194     }
 195     QString message(QString::fromUtf8(uMsg));
 196     socket->write(ack, qstrlen(ack));
 197     socket->waitForBytesWritten(1000);
 198     delete socket;
 199     emit messageReceived(message); //### (might take a long time to return)
 200 }