Safely close database connections and delete backends

Also fix NewClosure leak caused by disconnected object signals

src/qobuz/qobuzbaserequest.cpp

@@ -51,7 +51,7 @@ QobuzBaseRequest::~QobuzBaseRequest() {
 
   while (!replies_.isEmpty()) {
     QNetworkReply *reply = replies_.takeFirst();
-    disconnect(reply, 0, nullptr, 0);
+    disconnect(reply, 0, this, 0);
     if (reply->isRunning()) reply->abort();
     reply->deleteLater();
   }

src/qobuz/qobuzfavoriterequest.cpp

@@ -49,7 +49,7 @@ QobuzFavoriteRequest::~QobuzFavoriteRequest() {
 
   while (!replies_.isEmpty()) {
     QNetworkReply *reply = replies_.takeFirst();
-    disconnect(reply, 0, nullptr, 0);
+    disconnect(reply, 0, this, 0);
     reply->abort();
     reply->deleteLater();
   }

src/qobuz/qobuzrequest.cpp

@@ -77,7 +77,7 @@ QobuzRequest::~QobuzRequest() {
 
   while (!album_cover_replies_.isEmpty()) {
     QNetworkReply *reply = album_cover_replies_.takeFirst();
-    disconnect(reply, 0, nullptr, 0);
+    disconnect(reply, 0, this, 0);
     if (reply->isRunning()) reply->abort();
     reply->deleteLater();
   }

src/qobuz/qobuzservice.cpp

@@ -176,13 +176,35 @@ QobuzService::~QobuzService() {
 
   while (!stream_url_requests_.isEmpty()) {
     QobuzStreamURLRequest *stream_url_req = stream_url_requests_.takeFirst();
-    disconnect(stream_url_req, 0, nullptr, 0);
+    disconnect(stream_url_req, 0, this, 0);
     stream_url_req->deleteLater();
   }
 
-  artists_collection_backend_->deleteLater();
-  albums_collection_backend_->deleteLater();
-  songs_collection_backend_->deleteLater();
+  delete artists_collection_backend_;
+  delete albums_collection_backend_;
+  delete songs_collection_backend_;
+
+}
+
+void QobuzService::Exit() {
+
+  wait_for_exit_ << artists_collection_backend_ << albums_collection_backend_ << songs_collection_backend_;
+
+  connect(artists_collection_backend_, SIGNAL(ExitFinished()), this, SLOT(ExitReceived()));
+  connect(albums_collection_backend_, SIGNAL(ExitFinished()), this, SLOT(ExitReceived()));
+  connect(songs_collection_backend_, SIGNAL(ExitFinished()), this, SLOT(ExitReceived()));
+
+  artists_collection_backend_->ExitAsync();
+  albums_collection_backend_->ExitAsync();
+  songs_collection_backend_->ExitAsync();
+
+}
+
+void QobuzService::ExitReceived() {
+
+  disconnect(sender(), 0, this, 0);
+  wait_for_exit_.removeAll(sender());
+  if (wait_for_exit_.isEmpty()) emit ExitFinished();
 
 }
 
@@ -395,7 +417,7 @@ void QobuzService::TryLogin() {
 void QobuzService::ResetArtistsRequest() {
 
   if (artists_request_.get()) {
-    disconnect(artists_request_.get(), 0, nullptr, 0);
+    disconnect(artists_request_.get(), 0, this, 0);
     disconnect(this, 0, artists_request_.get(), 0);
     artists_request_.reset();
   }
@@ -446,7 +468,7 @@ void QobuzService::ArtistsUpdateProgressReceived(const int id, const int progres
 void QobuzService::ResetAlbumsRequest() {
 
   if (albums_request_.get()) {
-    disconnect(albums_request_.get(), 0, nullptr, 0);
+    disconnect(albums_request_.get(), 0, this, 0);
     disconnect(this, 0, albums_request_.get(), 0);
     albums_request_.reset();
   }
@@ -495,7 +517,7 @@ void QobuzService::AlbumsUpdateProgressReceived(const int id, const int progress
 void QobuzService::ResetSongsRequest() {
 
   if (songs_request_.get()) {
-    disconnect(songs_request_.get(), 0, nullptr, 0);
+    disconnect(songs_request_.get(), 0, this, 0);
     disconnect(this, 0, songs_request_.get(), 0);
     songs_request_.reset();
   }

src/qobuz/qobuzservice.h

@@ -40,6 +40,7 @@
 #include "internet/internetsearch.h"
 #include "settings/qobuzsettingspage.h"
 
+class QThread;
 class Application;
 class NetworkAccessManager;
 class QobuzUrlHandler;
@@ -60,6 +61,7 @@ class QobuzService : public InternetService {
 
   static const Song::Source kSource;
 
+  void Exit();
   void ReloadSettings();
 
   void Logout();
@@ -123,6 +125,7 @@ class QobuzService : public InternetService {
   void ResetSongsRequest();
 
  private slots:
+  void ExitReceived();
   void SendLogin();
   void HandleLoginSSLErrors(QList<QSslError> ssl_errors);
   void HandleAuthReply(QNetworkReply *reply);
@@ -217,6 +220,8 @@ class QobuzService : public InternetService {
 
   QStringList login_errors_;
 
+  QList<QObject*> wait_for_exit_;
+
 };
 
 #endif  // QOBUZSERVICE_H

src/qobuz/qobuzstreamurlrequest.cpp

@@ -54,7 +54,7 @@ QobuzStreamURLRequest::QobuzStreamURLRequest(QobuzService *service, NetworkAcces
 QobuzStreamURLRequest::~QobuzStreamURLRequest() {
 
   if (reply_) {
-    disconnect(reply_, 0, nullptr, 0);
+    disconnect(reply_, 0, this, 0);
     if (reply_->isRunning()) reply_->abort();
     reply_->deleteLater();
   }
@@ -107,7 +107,7 @@ void QobuzStreamURLRequest::GetStreamURL() {
   ++tries_;
 
   if (reply_) {
-    disconnect(reply_, 0, nullptr, 0);
+    disconnect(reply_, 0, this, 0);
     if (reply_->isRunning()) reply_->abort();
     reply_->deleteLater();
   }
@@ -147,7 +147,7 @@ void QobuzStreamURLRequest::GetStreamURL() {
 void QobuzStreamURLRequest::StreamURLReceived() {
 
   if (!reply_) return;
-  disconnect(reply_, 0, nullptr, 0);
+  disconnect(reply_, 0, this, 0);
   reply_->deleteLater();
 
   QByteArray data = GetReplyData(reply_);