Fix random crashes in ArchiveCollector

This was a hard one, actually. Since we only returned a pointer from the
ArchiveCollector, it worked _most_ of the time, but crashed at random
when the view was reading the tree while the collector was updating it.

So create a working copy constructor for SmRootItem and return a copy of
the the tree when the collector is done.

I bet that's also the reason for the random crashes in the filesystem
view.

1 files changed, 23 insertions, 9 deletions

diff --git a/archivemodel.cpp b/archivemodel.cpp
index b0a6941..86a478e 100644
--- a/archivemodel.cpp
+++ b/archivemodel.cpp
@@ -5,8 +5,8 @@
   2 of the License, or (at your option) any later version.
 */
 
-#include <QSqlError>
 #include <QSqlQuery>
+#include <QSqlError>
 #include <QFile>
 #include <QSettings>
 #include <QMutexLocker>
@@ -102,7 +102,9 @@ bool ArchiveModel::setData(const QModelIndex &idx, const QVariant &value, int ro
     QVariant id = item->data(GenericId);
     updateQuery.bindValue(":value", value);
     updateQuery.bindValue(":id", id);
+    mDb.transaction();
     if(updateQuery.exec()){
+        mDb.commit();
         item->setData(Name, value);
         emit dataChanged(idx, idx);
         if(nodeType == SeriesNode){
@@ -110,8 +112,8 @@ bool ArchiveModel::setData(const QModelIndex &idx, const QVariant &value, int ro
             return true;
         }
         writeCache(mOrder, root());
-        return true;
     }else{
+        mDb.rollback();
         emitDatabaseError(updateQuery.lastError());
     }
     return false;
@@ -226,22 +228,23 @@ void ArchiveModel::setOrder(const QString &order){
 void ArchiveModel::refresh(){
     emit message(tr("Reading archive data..."));
     foreach(ArchiveCollector *c, mCollectors){
-        c->start();
+        if(!c->isRunning()){
+            c->start();
+        }
     }
 }
 
 void ArchiveModel::collectorFinished(QObject *thread){
     QMutexLocker l(&mDoneMx);
     ArchiveCollector *t = qobject_cast<ArchiveCollector*>(thread);
-    Q_ASSERT(t);
-    SmTreeItem *item = t->rootItem();
+    SmTreeItem *rootCopy = t->rootItem();
     int sortOrder = t->sortOrder();
     if(sortOrder == mOrder){
         emit collectorAboutToBeDone();
-        setRoot(item);
+        setRoot(rootCopy);
         emit collectorDone();
     }
-    writeCache(sortOrder, item);
+    writeCache(sortOrder, rootCopy);
     QString sortOrderName = mAvailableOrders.key(sortOrder);
     QString msg = QString("Done reading %1").arg(sortOrderName);
     emit message(msg);
@@ -353,14 +356,24 @@ const QString ArchiveModel::cacheFile(int o) const{
     return cacheFile;
 }
 
-ArchiveCollector::ArchiveCollector(int numFields, int order, QObject *parent) : QThread(parent), mNumFields(numFields), mSortOrder(order) {
+ArchiveCollector::ArchiveCollector(int numFields, int order, QObject *parent) : QThread(parent), mRootItem(0), mNumFields(numFields), mSortOrder(order) {
     QString dbName = QString("%1").arg((qint64(this)));
     mDb = QSqlDatabase::cloneDatabase(QSqlDatabase::database("treedb"), dbName);
     mDb.open();
-    mRootItem = new SmTreeItem(numFields);
+    //mRootItem = new SmTreeItem(numFields);
+}
+
+SmTreeItem *ArchiveCollector::rootItem(){
+    mAccessMx.lock();
+    SmTreeItem *retval = new SmTreeItem(*mRootItem);
+    mAccessMx.unlock();
+    return retval;
 }
 
 void ArchiveCollector::run(){
+    mAccessMx.lock();
+    delete mRootItem;
+    mRootItem = new SmTreeItem(mNumFields);
     switch (mSortOrder){
         case ArchiveModel::SeriesName:
             populateBySeriesName();
@@ -374,6 +387,7 @@ void ArchiveCollector::run(){
         default:
             return;
     }
+    mAccessMx.unlock();
 }
 
 void ArchiveCollector::populateBySeriesName() {