Handle server application closure more cleanly

Jamulus.pro

@@ -210,7 +210,8 @@ HEADERS += src/audiomixerboard.h \
     src/recorder/jamrecorder.h \
     src/recorder/creaperproject.h \
     src/recorder/cwavestream.h \
-    src/historygraph.h
+    src/historygraph.h \
+    src/signalhandler.h
 
 HEADERS_OPUS = libs/opus/celt/arch.h \
     libs/opus/celt/bands.h \
@@ -324,6 +325,7 @@ SOURCES += src/audiomixerboard.cpp \
     src/serverlist.cpp \
     src/serverlogging.cpp \
     src/settings.cpp \
+    src/signalhandler.cpp \
     src/socket.cpp \
     src/soundbase.cpp \
     src/util.cpp \

src/client.cpp

@@ -1207,7 +1207,7 @@ fflush(pFileDelay);
     // update socket buffer size
     Channel.UpdateSocketBufferSize();
 
-    Q_UNUSED ( iUnused );
+    Q_UNUSED ( iUnused )
 }
 
 int CClient::EstimatedOverallDelay ( const int iPingTimeMs )

src/recorder/jamrecorder.cpp

@@ -327,9 +327,18 @@ void CJamRecorder::Init( const CServer* server,
                       this, SLOT(  OnFrame (const int, const QString, const CHostAddress, const int, const CVector<int16_t> ) ),
                       Qt::ConnectionType::QueuedConnection );
 
+    QObject::connect( QCoreApplication::instance(),
+                      SIGNAL ( aboutToQuit() ),
+                      this, SLOT( OnAboutToQuit() ) );
+
     iServerFrameSizeSamples = _iServerFrameSizeSamples;
+
+    thisThread = new QThread();
+    moveToThread ( thisThread );
+    thisThread->start();
 }
 
+
 /**
  * @brief CJamRecorder::OnStart Start up tasks when the first client connects
  */
@@ -372,6 +381,13 @@ void CJamRecorder::OnEnd()
     }
 }
 
+void CJamRecorder::OnAboutToQuit()
+{
+    OnEnd();
+
+    thisThread->exit();
+}
+
 /**
  * @brief CJamRecorder::SessionDirToReaper Replica of CJamRecorder::OnEnd() but using the directory contents to construct the CReaperProject object
  * @param strSessionDirName

src/recorder/jamrecorder.h

@@ -132,13 +132,16 @@ private:
     QList<CJamClientConnection*> jamClientConnections;
 };
 
-class CJamRecorder : public QThread
+class CJamRecorder : public QObject
 {
     Q_OBJECT
 
 public:
     CJamRecorder ( const QString recordingDirName ) :
-        recordBaseDir (recordingDirName), isRecording (false) {}
+        recordBaseDir ( recordingDirName ),
+        isRecording   ( false )
+    {
+    }
 
     void Init( const CServer* server, const int _iServerFrameSizeSamples );
 
@@ -155,6 +158,11 @@ public slots:
      */
     void OnEnd();
 
+    /**
+     * @brief Raised when application is stopping
+     */
+    void OnAboutToQuit();
+
     /**
      * @brief Raised when an existing client leaves the server.
      * @param iChID channel number of client
@@ -162,7 +170,7 @@ public slots:
     void OnDisconnected ( int iChID );
 
     /**
-     * @brief Raised when a frame of data fis available to process
+     * @brief Raised when a frame of data is available to process
      */
     void OnFrame ( const int iChID, const QString name, const CHostAddress address, const int numAudioChannels, const CVector<int16_t> data );
 
@@ -172,6 +180,8 @@ private:
     bool         isRecording;
     CJamSession* currentSession;
     int          iServerFrameSizeSamples;
+
+    QThread* thisThread;
 };
 
 }

src/server.cpp

@@ -398,11 +398,10 @@ CServer::CServer ( const int          iNewMaxNumChan,
             QString().number( static_cast<int> ( iPortNumber ) ) );
     }
 
-    // Enable jam recording (if requested)
+    // Enable jam recording (if requested) - kicks off the thread
     if ( bEnableRecording )
     {
         JamRecorder.Init ( this, iServerFrameSizeSamples );
-        JamRecorder.start();
     }
 
     // enable all channels (for the server all channel must be enabled the
@@ -466,6 +465,14 @@ CServer::CServer ( const int          iNewMaxNumChan,
        SIGNAL ( SvrRegStatusChanged() ),
        this, SLOT ( OnSvrRegStatusChanged() ) );
 
+    QObject::connect ( QCoreApplication::instance(),
+        SIGNAL ( aboutToQuit() ),
+        this, SLOT ( OnAboutToQuit() ) );
+
+    QObject::connect ( pSignalHandler,
+        SIGNAL ( ShutdownSignal ( int ) ),
+        this, SLOT ( OnShutdown ( int ) ) );
+
 #if QT_VERSION >= QT_VERSION_CHECK(5, 0, 0)
     connectChannelSignalsToServerSlots<MAX_NUM_CHANNELS>();
 
@@ -908,6 +915,54 @@ void CServer::OnCLDisconnection ( CHostAddress InetAddr )
     }
 }
 
+void CServer::OnAboutToQuit()
+{
+    if ( IsRunning() )
+    {
+        // Clean up
+        CleanShutdown();
+    }
+
+    // if server was registered at the central server, unregister on shutdown
+    if ( GetServerListEnabled() )
+    {
+        UnregisterSlaveServer();
+    }
+}
+
+void CServer::OnShutdown ( int )
+{
+    // This should trigger OnAboutToQuit
+    QCoreApplication::instance()->exit();
+}
+
+
+void CServer::CleanShutdown() {
+    Mutex.lock();
+    {
+        bool oldDAC = bDisconnectAllClients;
+
+        // This is to prevent new connections
+        bDisconnectAllClients = true;
+
+        // This is to disconnect all connected channels
+        for ( int i = 0; i < iMaxNumChannels; i++ )
+        {
+            if ( vecChannels[i].IsConnected() )
+            {
+                vecChannels[i].Disconnect();
+            }
+        }
+
+        // This should tell the jam recorder than the jam has ended...
+        Stop();
+
+        // Restore the value in case we are not exiting
+        bDisconnectAllClients = oldDAC;
+    }
+    Mutex.unlock();
+}
+
 void CServer::Start()
 {
     // only start if not already running
@@ -1273,7 +1328,7 @@ opus_custom_encoder_ctl ( CurOpusEncoder,
         Stop();
     }
 
-    Q_UNUSED ( iUnused );
+    Q_UNUSED ( iUnused )
 }
 
 /// @brief Mix all audio data from all clients together.

src/server.h

@@ -36,6 +36,7 @@
 #endif
 #include "global.h"
 #include "buffer.h"
+#include "signalhandler.h"
 #include "socket.h"
 #include "channel.h"
 #include "util.h"
@@ -257,6 +258,8 @@ protected:
     int GetNumberOfConnectedClients();
     CVector<CChannelInfo> CreateChannelList();
 
+    CSignalHandler* pSignalHandler = CSignalHandler::getSingletonP();
+
 #if QT_VERSION >= QT_VERSION_CHECK(5, 0, 0)
     virtual void CreateAndSendChanListForAllConChannels();
     virtual void CreateAndSendChanListForThisChan ( const int iCurChanID );
@@ -303,6 +306,8 @@ protected:
                                           const CVector<CVector<int16_t> > vecvecsData,
                                           CVector<uint16_t>&               vecLevelsOut );
 
+    void CleanShutdown();
+
     // do not use the vector class since CChannel does not have appropriate
     // copy constructor/operator
     CChannel                   vecChannels[MAX_NUM_CHANNELS];
@@ -455,6 +460,10 @@ public slots:
 
     void OnCLDisconnection ( CHostAddress InetAddr );
 
+    void OnAboutToQuit();
+
+    void OnShutdown ( int );
+
 #if QT_VERSION < 0x50000  // MOC does not expand macros in Qt 4, so we cannot use QT_VERSION_CHECK(5, 0, 0)
     // CODE TAG: MAX_NUM_CHANNELS_TAG
     // make sure we have MAX_NUM_CHANNELS connections!!!

src/serverdlg.cpp

@@ -342,18 +342,6 @@ lvwClients->setMinimumHeight ( 140 );
     Timer.start ( GUI_CONTRL_UPDATE_TIME );
 }
 
-void CServerDlg::closeEvent ( QCloseEvent* Event )
-{
-    // if server was registered at the central server, unregister on shutdown
-    if ( pServer->GetServerListEnabled() )
-    {
-        pServer->UnregisterSlaveServer();
-    }
-
-    // default implementation of this event handler routine
-    Event->accept();
-}
-
 void CServerDlg::OnStartOnOSStartStateChanged ( int value )
 {
     const bool bCurAutoStartMinState = ( value == Qt::Checked );

src/serverdlg.h

@@ -58,7 +58,6 @@ public:
 
 protected:
     virtual void changeEvent ( QEvent* pEvent );
-    virtual void closeEvent  ( QCloseEvent* Event );
 
     void         UpdateGUIDependencies();
     void         UpdateSystemTrayIcon ( const bool bIsActive );

src/signalhandler.cpp

@@ -0,0 +1,146 @@
+/******************************************************************************\
+ * Copyright (c) 2020
+ *
+ * Author(s):
+ *  Peter L Jones
+ *
+ ******************************************************************************
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 2 of the License, or (at your option) any later
+ * version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+\******************************************************************************/
+
+#include "signalhandler.h"
+
+class CSignalHandlerSingleton : public CSignalHandler {
+public:
+    inline CSignalHandlerSingleton() : CSignalHandler() {}
+};
+Q_GLOBAL_STATIC ( CSignalHandlerSingleton, singleton )
+
+CSignalHandler::CSignalHandler() : pSignalBase ( CSignalBase::withSignalHandler ( this ) ) {}
+
+CSignalHandler::~CSignalHandler() = default;
+
+CSignalHandler* CSignalHandler::getSingletonP() { return singleton; }
+
+bool CSignalHandler::emitSignal ( int sigNum )
+{
+    return QMetaObject::invokeMethod( singleton, "ShutdownSignal", Qt::QueuedConnection, Q_ARG( int, sigNum ) );
+}
+
+#ifndef _WIN32
+void CSignalHandler::OnSocketNotify( int socket )
+{
+    int sigNum;
+    if ( ::read ( socket, &sigNum, sizeof ( int ) ) == sizeof ( int ) )
+    {
+        emitSignal ( sigNum );
+    }
+}
+#endif
+
+// ----------------------------------------------------------
+
+CSignalBase::CSignalBase ( CSignalHandler* pSignalHandler ) :
+    pSignalHandler ( pSignalHandler )
+{
+}
+
+CSignalBase::~CSignalBase() = default;
+
+CSignalBase* CSignalBase::withSignalHandler ( CSignalHandler* pSignalHandler )
+{
+#ifdef _WIN32
+    return new CSignalWin ( pSignalHandler );
+#else
+    return new CSignalUnix ( pSignalHandler );
+#endif
+}
+
+#ifdef _WIN32
+CSignalWin::CSignalWin ( CSignalHandler* nPSignalHandler ) :
+    CSignalBase ( nPSignalHandler ),
+    lock ( QReadWriteLock::Recursive )
+{
+    SetConsoleCtrlHandler ( signalHandler, true );
+}
+
+CSignalWin::~CSignalWin() {
+    SetConsoleCtrlHandler ( signalHandler, false );
+}
+
+QReadWriteLock* CSignalWin::getLock() const
+{
+    return &lock;
+}
+
+BOOL WINAPI CSignalWin::signalHandler ( _In_ DWORD sigNum )
+{
+    auto self = getSelf<CSignalWin>();
+    QReadLocker lock ( self->getLock() );
+    return self->pSignalHandler->emitSignal ( static_cast<int>( sigNum ) );
+}
+
+#else
+int CSignalUnix::socketPair[2];
+
+CSignalUnix::CSignalUnix ( CSignalHandler* nPSignalHandler ) :
+    CSignalBase ( nPSignalHandler )
+{
+    if ( ::socketpair ( AF_UNIX, SOCK_STREAM, 0, socketPair ) == 0 )
+    {
+        socketNotifier = new QSocketNotifier ( socketPair[ 1 ], QSocketNotifier::Read );
+
+        QObject::connect ( socketNotifier, &QSocketNotifier::activated, nPSignalHandler, &CSignalHandler::OnSocketNotify );
+
+        socketNotifier->setEnabled ( true );
+
+        setSignalHandled ( SIGINT, true );
+        setSignalHandled ( SIGTERM, true );
+    }
+}
+
+CSignalUnix::~CSignalUnix() {
+    setSignalHandled ( SIGINT, false );
+    setSignalHandled ( SIGTERM, false );
+}
+
+QReadWriteLock* CSignalUnix::getLock() const { return nullptr; }
+
+bool CSignalUnix::setSignalHandled ( int sigNum, bool state )
+{
+    struct sigaction sa;
+    sigemptyset ( &sa.sa_mask );
+
+    if ( state )
+    {
+        sa.sa_handler = CSignalUnix::signalHandler;
+        sa.sa_flags |= SA_RESTART;
+    }
+    else
+    {
+        sa.sa_handler = SIG_DFL;
+    }
+
+    return ::sigaction ( sigNum, &sa, nullptr ) == 0;
+}
+
+void CSignalUnix::signalHandler ( int sigNum )
+{
+    const auto res = ::write ( socketPair[ 0 ], &sigNum, sizeof ( int ) );
+    Q_UNUSED ( res );
+}
+#endif

src/signalhandler.h

@@ -0,0 +1,140 @@
+/******************************************************************************\
+ * Copyright (c) 2020
+ *
+ * Author(s):
+ *  Peter L Jones
+ *
+ ******************************************************************************
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 2 of the License, or (at your option) any later
+ * version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+\******************************************************************************/
+
+#pragma once
+
+#include <QtCore/QObject>
+#include <QtCore/QScopedPointer>
+#include <QtCore/QHash>
+#include <QtCore/QReadWriteLock>
+#include <QtCore/QSet>
+#include <QGlobalStatic>
+
+#ifdef _WIN32
+#include <qt_windows.h>
+#include <QtCore/QCoreApplication>
+#include <QtCore/QSemaphore>
+#include <QtCore/QThread>
+#include <QtCore/QDebug>
+#else
+#include <QSocketNotifier>
+#include <QObject>
+#include <QCoreApplication>
+#include <csignal>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#endif
+
+class CSignalBase;
+
+class CSignalHandler : public QObject
+{
+    Q_OBJECT
+
+    friend class CSignalBase;
+    friend class CSignalHandlerSingleton;
+
+public:
+    static CSignalHandler* getSingletonP();
+
+    bool emitSignal ( int );
+
+#ifndef _WIN32
+public slots:
+    void OnSocketNotify ( int socket );
+#endif
+
+signals:
+    void ShutdownSignal ( int sigNum );
+
+private:
+    QScopedPointer<CSignalBase> pSignalBase;
+
+    explicit CSignalHandler();
+    ~CSignalHandler() override;
+};
+
+// ----------------------------------------------------------
+
+class CSignalBase
+{
+    Q_DISABLE_COPY ( CSignalBase )
+
+public:
+    static CSignalBase* withSignalHandler ( CSignalHandler* );
+    virtual ~CSignalBase();
+
+    virtual QReadWriteLock* getLock() const = 0;
+
+    QSet<int> sHandledSigNums;
+
+protected:
+    CSignalBase ( CSignalHandler* );
+
+    CSignalHandler* pSignalHandler;
+
+    template <typename T>
+    static T *getSelf()
+    {
+        return static_cast<T*>( CSignalHandler::getSingletonP()->pSignalBase.data() );
+    }
+
+};
+
+#ifdef _WIN32
+
+class CSignalWin : public CSignalBase
+{
+public:
+    CSignalWin ( CSignalHandler* );
+    ~CSignalWin() override;
+
+    virtual QReadWriteLock* getLock() const override;
+
+private:
+    mutable QReadWriteLock lock;
+
+    static BOOL WINAPI signalHandler ( _In_ DWORD sigNum );
+};
+
+#else
+
+class CSignalUnix : public CSignalBase
+{
+public:
+    CSignalUnix ( CSignalHandler* );
+    ~CSignalUnix() override;
+
+    virtual QReadWriteLock* getLock() const override;
+
+private:
+    QSocketNotifier* socketNotifier = nullptr;
+    bool setSignalHandled ( int sigNum, bool state );
+
+    static int socketPair[2];
+    static void signalHandler ( int sigNum );
+};
+
+#endif