Dealing with cdio_open failures in CddaDevice constructor

src/CMakeLists.txt

@@ -122,6 +122,7 @@ set(SOURCES
 
   devices/connecteddevice.cpp
   devices/devicedatabasebackend.cpp
+  devices/deviceerror.cpp
   devices/devicelister.cpp
   devices/devicemanager.cpp
   devices/deviceproperties.cpp
@@ -458,6 +459,7 @@ set(HEADERS
 
   devices/connecteddevice.h
   devices/devicedatabasebackend.h
+  devices/deviceerror.h
   devices/devicelister.h
   devices/devicemanager.h
   devices/deviceproperties.h

src/devices/cddadevice.cpp

@@ -17,6 +17,7 @@
 
 #include "cddadevice.h"
 
+#include "deviceerror.h"
 #include "library/librarybackend.h"
 #include "library/librarymodel.h"
 
@@ -41,7 +42,10 @@ CddaDevice::CddaDevice(const QUrl& url, DeviceLister* lister,
           SLOT(SongsDiscovered(SongList)));
   //   connect(&cd_device_, SIGNAL(DiscChanged()), SLOT(DiscChangeDetected()));
   cdio_ = cdio_open(url_.path().toLocal8Bit().constData(), DRIVER_DEVICE);
-  Q_ASSERT(cdio_);  // todo: error handling?
+  if (!cdio_) {
+    throw DeviceError(url.toString(),
+                      "Cannot open device: cdio_open returned nullptr");
+  }
   connect(&disc_changed_timer_, SIGNAL(timeout()), SLOT(CheckDiscChanged()));
   WatchForDiscChanges(watch_for_disc_changes);
 }

src/devices/deviceerror.cpp

@@ -0,0 +1,37 @@
+/* This file is part of Clementine.
+   Copyright 2021, Lukas Prediger <lumip@lumip.de>
+
+   Clementine 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 3 of the License, or
+   (at your option) any later version.
+
+   Clementine 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 Clementine.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "deviceerror.h"
+
+#include <QString>
+
+std::string DeviceError::CreateExceptionMessage(const QString& device_id,
+                                                const QString error_message) {
+  QString exception_message =
+      QString("Error accessing device <%1>").arg(device_id);
+  if (!error_message.isEmpty()) exception_message += ": " + error_message;
+
+  return exception_message.toLocal8Bit().toStdString();
+}
+
+DeviceError::DeviceError(const QString& device_id, const QString& error_message)
+    : std::runtime_error(CreateExceptionMessage(device_id, error_message)) {}
+
+DeviceError::DeviceError(const QString& device_id)
+    : DeviceError(device_id, "") {}
+
+DeviceError::~DeviceError() {}

src/devices/deviceerror.h

@@ -0,0 +1,36 @@
+/* This file is part of Clementine.
+   Copyright 2021, Lukas Prediger <lumip@lumip.de>
+
+   Clementine 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 3 of the License, or
+   (at your option) any later version.
+
+   Clementine 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 Clementine.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef DEVICEERROR_H
+#define DEVICEERROR_H
+
+#include <stdexcept>
+
+class QString;
+
+class DeviceError : public std::runtime_error {
+ private:
+  static std::string CreateExceptionMessage(const QString& device_id,
+                                            const QString error_message);
+
+ public:
+  DeviceError(const QString& device_id);
+  DeviceError(const QString& device_id, const QString& error_message);
+  virtual ~DeviceError();
+};
+
+#endif

src/devices/devicemanager.cpp

@@ -37,6 +37,7 @@
 #include "core/taskmanager.h"
 #include "core/utilities.h"
 #include "devicedatabasebackend.h"
+#include "deviceerror.h"
 #include "deviceinfo.h"
 #include "devicestatefiltermodel.h"
 #include "filesystemdevice.h"
@@ -347,7 +348,7 @@ DeviceInfo* DeviceManager::FindEquivalentDevice(DeviceInfo* info) const {
   return nullptr;
 }
 
-QList<DeviceInfo*> DeviceManager::FindDeviceByUrlSchemes(
+QList<DeviceInfo*> DeviceManager::FindDevicesByUrlSchemes(
     QStringList url_schemes) const {
   QList<DeviceInfo*> matches;
   for (DeviceInfo* device_info : devices_) {
@@ -565,14 +566,19 @@ std::shared_ptr<ConnectedDevice> DeviceManager::Connect(DeviceInfo* info) {
     return ret;
   }
 
-  QMetaObject meta_object = device_classes_.value(device_url.scheme());
-  QObject* instance = meta_object.newInstance(
-      Q_ARG(QUrl, device_url),
-      Q_ARG(DeviceLister*, info->BestBackend()->lister_),
-      Q_ARG(QString, info->BestBackend()->unique_id_),
-      Q_ARG(DeviceManager*, this), Q_ARG(Application*, app_),
-      Q_ARG(int, info->database_id_), Q_ARG(bool, first_time));
-  ret.reset(static_cast<ConnectedDevice*>(instance));
+  try {
+    QMetaObject meta_object = device_classes_.value(device_url.scheme());
+    QObject* instance = meta_object.newInstance(
+        Q_ARG(QUrl, device_url),
+        Q_ARG(DeviceLister*, info->BestBackend()->lister_),
+        Q_ARG(QString, info->BestBackend()->unique_id_),
+        Q_ARG(DeviceManager*, this), Q_ARG(Application*, app_),
+        Q_ARG(int, info->database_id_), Q_ARG(bool, first_time));
+    ret.reset(static_cast<ConnectedDevice*>(instance));
+  } catch (const DeviceError& e) {
+    qLog(Warning) << "Could not create device: " << e.what();
+    return ret;
+  }
 
   if (!ret) {
     qLog(Warning) << "Could not create device for" << device_url.toString();

src/devices/devicemanager.h

@@ -78,7 +78,7 @@ class DeviceManager : public SimpleTreeModel<DeviceInfo> {
   DeviceInfo* FindDeviceById(const QString& id) const;
   DeviceInfo* FindDeviceByUrl(const QList<QUrl>& url) const;
   DeviceInfo* FindEquivalentDevice(DeviceInfo* info) const;
-  QList<DeviceInfo*> FindDeviceByUrlSchemes(QStringList url_schemes) const;
+  QList<DeviceInfo*> FindDevicesByUrlSchemes(QStringList url_schemes) const;
 
   // Actions on devices
   std::shared_ptr<ConnectedDevice> Connect(DeviceInfo* info);

src/ripper/ripcddialog.cpp

@@ -59,7 +59,7 @@ RipCDDialog::RipCDDialog(DeviceManager& device_manager, QWidget* parent)
       ui_(new Ui_RipCDDialog),
       device_manager_(device_manager),
       cdda_devices_(
-          device_manager.FindDeviceByUrlSchemes(CddaDevice::url_schemes())),
+          device_manager.FindDevicesByUrlSchemes(CddaDevice::url_schemes())),
       working_(false),
       cdda_device_(),
       loader_(nullptr) {