Some NULL-safety changes.

10 files changed, 93 insertions, 40 deletions

diff --git a/src/dlgcoverartfullsize.cpp b/src/dlgcoverartfullsize.cpp
index bb3a05743d..debd0bc480 100644
--- a/src/dlgcoverartfullsize.cpp
+++ b/src/dlgcoverartfullsize.cpp
@@ -20,6 +20,10 @@ void DlgCoverArtFullSize::init(CoverInfo info) {
     }
 
     CoverArtCache* cache = CoverArtCache::instance();
+    if (cache == NULL) {
+        return;
+    }
+
     if (info.coverLocation.isEmpty()) {
         info.coverLocation = cache->trackInDBHash(info.trackId);
     }
diff --git a/src/dlgtrackinfo.cpp b/src/dlgtrackinfo.cpp
index 29cc411d10..d8dd78bff9 100644
--- a/src/dlgtrackinfo.cpp
+++ b/src/dlgtrackinfo.cpp
@@ -80,8 +80,11 @@ void DlgTrackInfo::init(){
         m_bpmTapFilter[i] = 0.0f;
     }
 
-    connect(CoverArtCache::instance(), SIGNAL(pixmapFound(int, QPixmap)),
-            this, SLOT(slotPixmapFound(int, QPixmap)));
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache != NULL) {
+        connect(pCache, SIGNAL(pixmapFound(int, QPixmap)),
+                this, SLOT(slotPixmapFound(int, QPixmap)));
+    }
     connect(m_pWCoverArtLabel,
             SIGNAL(coverLocationUpdated(const QString&, const QString&, QPixmap)),
             this,
@@ -187,7 +190,10 @@ void DlgTrackInfo::loadTrack(TrackPointer pTrack, CoverInfo info) {
     connect(pTrack.data(), SIGNAL(changed(TrackInfoObject*)),
             this, SLOT(updateTrackMetadata()));
 
-    CoverArtCache::instance()->requestPixmap(info);
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache != NULL) {
+        pCache->requestPixmap(info);
+    }
 }
 
 void DlgTrackInfo::slotPixmapFound(int trackId, QPixmap pixmap) {
@@ -365,7 +371,12 @@ void DlgTrackInfo::saveTrack() {
         m_pLoadedTrack->removeCue(pCue);
     }
 
-    bool res = CoverArtCache::instance()->changeCoverArt(
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache == NULL) {
+        return;
+    }
+
+    bool res = pCache->changeCoverArt(
         m_pLoadedTrack->getId(), m_loadedCover.coverLocation);
 
     if (!res) {
diff --git a/src/library/coverartcache.cpp b/src/library/coverartcache.cpp
index c039729e96..cddea8327f 100644
--- a/src/library/coverartcache.cpp
+++ b/src/library/coverartcache.cpp
@@ -51,7 +51,7 @@ QString CoverArtCache::trackInDBHash(int trackId) {
 
 bool CoverArtCache::changeCoverArt(int trackId,
                                    const QString& newCoverLocation) {
-    if (trackId < 1) {
+    if (trackId < 1 || m_pCoverArtDAO == NULL || m_pTrackDAO == NULL) {
         return false;
     }
 
@@ -99,7 +99,7 @@ QPixmap CoverArtCache::requestPixmap(CoverInfo info,
                                      const QSize& croppedSize,
                                      const bool onlyCached,
                                      const bool issueRepaint) {
-    if (info.trackId < 1) {
+    if (info.trackId < 1 || m_pCoverArtDAO == NULL) {
         return QPixmap();
     }
 
diff --git a/src/library/coverartdelegate.cpp b/src/library/coverartdelegate.cpp
index a619b06681..3b9104a514 100644
--- a/src/library/coverartdelegate.cpp
+++ b/src/library/coverartdelegate.cpp
@@ -1,16 +1,19 @@
-#include <QPainter>
-
 #include "library/coverartdelegate.h"
+#include "library/coverartcache.h"
 #include "library/dao/trackdao.h"
 
 CoverArtDelegate::CoverArtDelegate(QObject *parent)
         : QStyledItemDelegate(parent),
-          m_pCoverCache(CoverArtCache::instance()),
           m_bOnlyCachedCover(false),
-          m_sDefaultCover(m_pCoverCache->getDefaultCoverLocation()),
           m_iCoverLocationColumn(-1),
           m_iCoverHashColumn(-1),
+          m_iTrackLocationColumn(-1),
           m_iIdColumn(-1) {
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache != NULL) {
+        m_sDefaultCover = pCache->getDefaultCoverLocation();
+    }
+
     // This assumes that the parent is wtracktableview
     connect(parent, SIGNAL(onlyCachedCoverArt(bool)),
             this, SLOT(slotOnlyCachedCoverArt(bool)));
@@ -63,6 +66,11 @@ void CoverArtDelegate::paint(QPainter *painter,
     QString coverLocation = index.sibling(
         index.row(), m_iCoverLocationColumn).data().toString();
 
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache == NULL) {
+        return;
+    }
+
     // drawing only an existing cover_art,
     // otherwise leave it blank...
     if (coverLocation != m_sDefaultCover) {
@@ -74,11 +82,12 @@ void CoverArtDelegate::paint(QPainter *painter,
         info.trackLocation = index.sibling(
             index.row(), m_iTrackLocationColumn).data().toString();
         QSize coverSize(100, option.rect.height());
-        QPixmap pixmap = m_pCoverCache->requestPixmap(info, coverSize,
-                                                      m_bOnlyCachedCover, true);
+
+        QPixmap pixmap = pCache->requestPixmap(info, coverSize,
+                                               m_bOnlyCachedCover, true);
 
         if (info.coverLocation.isEmpty()) {
-            info.coverLocation = m_pCoverCache->trackInDBHash(info.trackId);
+            info.coverLocation = pCache->trackInDBHash(info.trackId);
         }
 
         if (!pixmap.isNull() && info.coverLocation != m_sDefaultCover) {
diff --git a/src/library/coverartdelegate.h b/src/library/coverartdelegate.h
index 5a5d85c680..cfca4b7f7d 100644
--- a/src/library/coverartdelegate.h
+++ b/src/library/coverartdelegate.h
@@ -1,15 +1,15 @@
 #ifndef COVERARTDELEGATE_H
 #define COVERARTDELEGATE_H
 
+#include <QObject>
+#include <QPainter>
 #include <QStyledItemDelegate>
 #include <QTableView>
 
-#include "library/coverartcache.h"
 #include "library/trackmodel.h"
 
 class CoverArtDelegate : public QStyledItemDelegate {
-  Q_OBJECT
-
+    Q_OBJECT
   public:
     explicit CoverArtDelegate(QObject* parent = NULL);
     virtual ~CoverArtDelegate();
@@ -32,7 +32,6 @@ class CoverArtDelegate : public QStyledItemDelegate {
     void slotOnlyCachedCoverArt(bool b);
 
   private:
-    CoverArtCache* m_pCoverCache;
     bool m_bOnlyCachedCover;
     QString m_sDefaultCover;
     int m_iCoverLocationColumn;
diff --git a/src/mixxx.cpp b/src/mixxx.cpp
index 63f601fe5c..a780d11e39 100644
--- a/src/mixxx.cpp
+++ b/src/mixxx.cpp
@@ -297,10 +297,12 @@ MixxxMainWindow::MixxxMainWindow(QApplication* pApp, const CmdlineArgs& args)
         }
     }
 
-    CoverArtCache::instance()->setCoverArtDAO(
-        &m_pLibrary->getTrackCollection()->getCoverArtDAO());
-    CoverArtCache::instance()->setTrackDAO(
-        &m_pLibrary->getTrackCollection()->getTrackDAO());
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache != NULL) {
+        pCache->setCoverArtDAO(
+            &m_pLibrary->getTrackCollection()->getCoverArtDAO());
+        pCache->setTrackDAO(&m_pLibrary->getTrackCollection()->getTrackDAO());
+    }
 
     // Call inits to invoke all other construction parts
 
diff --git a/src/widget/wcoverart.cpp b/src/widget/wcoverart.cpp
index 082746b258..599f888501 100644
--- a/src/widget/wcoverart.cpp
+++ b/src/widget/wcoverart.cpp
@@ -13,17 +13,19 @@ WCoverArt::WCoverArt(QWidget* parent,
                      TrackCollection* pTrackCollection)
         : QWidget(parent),
           WBaseWidget(this),
-          m_pCoverCache(CoverArtCache::instance()),
           m_bEnableWidget(true),
           m_pMenu(new WCoverArtMenu(this)),
-          m_loadedCover(m_pCoverCache->getDefaultCoverArt()),
-          m_loadedCoverScaled(scaledCoverArt(m_loadedCover)),
           m_trackDAO(pTrackCollection->getTrackDAO()),
           m_pDlgFullSize(new DlgCoverArtFullSize()) {
     setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding);
 
-    connect(m_pCoverCache, SIGNAL(pixmapFound(int, QPixmap)),
-            this, SLOT(slotPixmapFound(int, QPixmap)), Qt::DirectConnection);
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache != NULL) {
+        connect(pCache, SIGNAL(pixmapFound(int, QPixmap)),
+                this, SLOT(slotPixmapFound(int, QPixmap)), Qt::DirectConnection);
+        m_loadedCover = pCache->getDefaultCoverArt();
+        m_loadedCoverScaled = scaledCoverArt(m_loadedCover);
+    }
     connect(m_pMenu,
             SIGNAL(coverLocationUpdated(const QString&, const QString&, QPixmap)),
             this,
@@ -64,7 +66,9 @@ void WCoverArt::slotCoverLocationUpdated(const QString& newLoc,
                                          QPixmap px) {
     Q_UNUSED(oldLoc);
     Q_UNUSED(px);
-    if (!m_pCoverCache->changeCoverArt(m_lastRequestedCover.trackId, newLoc)) {
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache != NULL && !pCache->changeCoverArt(
+            m_lastRequestedCover.trackId, newLoc)) {
         // parent must be NULL - it ensures the use of the default style.
         QMessageBox::warning(NULL, tr("Change Cover Art"),
                              tr("Could not change the cover art."));
@@ -82,8 +86,11 @@ void WCoverArt::slotEnableWidget(bool enable) {
 
 void WCoverArt::slotResetWidget() {
     m_lastRequestedCover = CoverInfo();
-    m_loadedCover = m_pCoverCache->getDefaultCoverArt();
-    m_loadedCoverScaled = scaledCoverArt(m_loadedCover);
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache != NULL) {
+        m_loadedCover = pCache->getDefaultCoverArt();
+        m_loadedCoverScaled = scaledCoverArt(m_loadedCover);
+    }
     update();
 }
 
@@ -103,7 +110,10 @@ void WCoverArt::slotLoadCoverArt(CoverInfo info, bool cachedOnly) {
         return;
     }
     m_lastRequestedCover = info;
-    m_pCoverCache->requestPixmap(info, QSize(0,0), cachedOnly);
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache != NULL) {
+        pCache->requestPixmap(info, QSize(0,0), cachedOnly);
+    }
 }
 
 QPixmap WCoverArt::scaledCoverArt(QPixmap normal) {
@@ -135,7 +145,10 @@ void WCoverArt::resizeEvent(QResizeEvent*) {
         setMaximumHeight(h);
     }
     if (m_lastRequestedCover.trackId < 1) {
-        m_loadedCover = m_pCoverCache->getDefaultCoverArt();
+        CoverArtCache* pCache = CoverArtCache::instance();
+        if (pCache != NULL) {
+            m_loadedCover = pCache->getDefaultCoverArt();
+        }
     }
     m_loadedCoverScaled = scaledCoverArt(m_loadedCover);
 }
diff --git a/src/widget/wcoverart.h b/src/widget/wcoverart.h
index 6e0fa12f42..98ef4b3f7b 100644
--- a/src/widget/wcoverart.h
+++ b/src/widget/wcoverart.h
@@ -42,7 +42,6 @@ class WCoverArt : public QWidget, public WBaseWidget {
   private:
     QPixmap scaledCoverArt(QPixmap normal);
 
-    CoverArtCache* m_pCoverCache;
     bool m_bEnableWidget;
     WCoverArtMenu* m_pMenu;
     QPixmap m_loadedCover;
diff --git a/src/widget/wcoverartmenu.cpp b/src/widget/wcoverartmenu.cpp
index 6cab7e5acd..dc8be5eb94 100644
--- a/src/widget/wcoverartmenu.cpp
+++ b/src/widget/wcoverartmenu.cpp
@@ -51,12 +51,16 @@ void WCoverArtMenu::slotChange() {
         return;
     }
 
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache == NULL) {
+        return;
+    }
+
     // get initial directory (trackdir or coverdir)
     QString initialDir;
     QString trackPath = m_pTrack->getDirectory();
     if (m_coverInfo.coverLocation.isEmpty() ||
-        m_coverInfo.coverLocation == CoverArtCache::instance()
-            ->getDefaultCoverLocation()) {
+            m_coverInfo.coverLocation == pCache->getDefaultCoverLocation()) {
         initialDir = trackPath;
     } else {
         initialDir = m_coverInfo.coverLocation;
@@ -111,14 +115,19 @@ void WCoverArtMenu::slotReload() {
     if (m_coverInfo.trackId < 1) {
         return;
     }
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache == NULL) {
+        return;
+    }
+
     CoverArtDAO::CoverArtInfo info;
     info.trackId = m_pTrack->getId();
     info.album = m_pTrack->getAlbum();
     info.trackDirectory = m_pTrack->getDirectory();
     info.trackLocation = m_pTrack->getLocation();
     info.trackBaseName = QFileInfo(m_pTrack->getFilename()).baseName();
-    CoverArtCache::FutureResult res =
-            CoverArtCache::instance()->searchImage(info, QSize(0,0), false);
+    CoverArtCache::FutureResult res = pCache->searchImage(
+        info, QSize(0,0), false);
     QPixmap px;
     px.convertFromImage(res.img);
     emit(coverLocationUpdated(res.coverLocation, m_coverInfo.coverLocation, px));
@@ -128,7 +137,11 @@ void WCoverArtMenu::slotUnset() {
     if (m_coverInfo.trackId < 1) {
         return;
     }
-    QString newLoc = CoverArtCache::instance()->getDefaultCoverLocation();
-    QPixmap px = CoverArtCache::instance()->getDefaultCoverArt();
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache == NULL) {
+        return;
+    }
+    QString newLoc = pCache->getDefaultCoverLocation();
+    QPixmap px = pCache->getDefaultCoverArt();
     emit(coverLocationUpdated(newLoc, m_coverInfo.coverLocation, px));
 }
diff --git a/src/widget/wtracktableview.cpp b/src/widget/wtracktableview.cpp
index 100c5518f2..d3a759db18 100644
--- a/src/widget/wtracktableview.cpp
+++ b/src/widget/wtracktableview.cpp
@@ -96,8 +96,11 @@ WTrackTableView::WTrackTableView(QWidget * parent,
     connect(this, SIGNAL(scrollValueChanged(int)),
             this, SLOT(slotScrollValueChanged(int)));
 
-    connect(CoverArtCache::instance(), SIGNAL(requestRepaint()),
-            this, SLOT(update()));
+    CoverArtCache* pCache = CoverArtCache::instance();
+    if (pCache != NULL) {
+        connect(pCache, SIGNAL(requestRepaint()),
+                this, SLOT(update()));
+    }
 }
 
 WTrackTableView::~WTrackTableView() {