new setup/teardown api for runners so we don't hang onto tons of data and live connections when not matching

svn path=/trunk/KDE/kdelibs/; revision=1003355

abstractrunner.h

@@ -244,6 +244,26 @@ class PLASMA_EXPORT AbstractRunner : public QObject
          */
         static QMutex *bigLock();
 
+    Q_SIGNALS:
+        /**
+         * This signal is emitted when matching is about to commence, giving runners
+         * an opportunity to prepare themselves, e.g. loading data sets or preparing
+         * IPC or network connections. This method should be fast so as not to cause
+         * slow downs. Things that take longer or which should be loaded once and
+         * remain extant for the lifespan of the AbstractRunner should be done in init().
+         * @see init()
+         * @since 4.4
+         */
+        void prepare();
+
+        /**
+         * This signal is emitted when a session of matches is complete, giving runners
+         * the opportunity to tear down anything set up as a result of the prepare()
+         * method.
+         * @since 4.4
+         */
+        void teardown();
+
     protected:
         friend class RunnerManager;
         friend class RunnerManagerPrivate;

runnermanager.cpp

@@ -56,7 +56,8 @@ public:
 
     RunnerManagerPrivate(RunnerManager *parent)
       : q(parent),
-        deferredRun(0)
+        deferredRun(0),
+        prepped(false)
     {
         matchChangeTimer.setSingleShot(true);
         delayTimer.setSingleShot(true);
@@ -218,8 +219,9 @@ public:
     QHash<QString, AbstractRunner*> runners;
     QSet<FindMatchesJob*> searchJobs;
     QSet<FindMatchesJob*> oldSearchJobs;
-    bool loadAll;
     KConfigGroup config;
+    bool loadAll : 1;
+    bool prepped : 1;
 };
 
 /*****************************************************
@@ -325,13 +327,39 @@ QList<QAction*> RunnerManager::actionsForMatch(const QueryMatch &match)
     return QList<QAction*>();
 }
 
+void RunnerManager::setupMatchSession()
+{
+    if (d->prepped) {
+        return;
+    }
+
+    foreach (AbstractRunner *runner, d->runners) {
+        emit runner->prepare();
+    }
+}
+
+void RunnerManager::matchSessionComplete()
+{
+    if (!d->prepped) {
+        return;
+    }
+
+    foreach (AbstractRunner *runner, d->runners) {
+        emit runner->teardown();
+    }
+
+    d->prepped = false;
+}
+
 void RunnerManager::launchQuery(const QString &term)
 {
+    setupMatchSession();
     launchQuery(term, QString());
 }
 
 void RunnerManager::launchQuery(const QString &untrimmedTerm, const QString &runnerName)
 {
+    setupMatchSession();
     QString term = untrimmedTerm.trimmed();
 
     if (d->runners.isEmpty()) {

runnermanager.h

@@ -105,6 +105,23 @@ class PLASMA_EXPORT RunnerManager : public QObject
         void reloadConfiguration();
 
     public Q_SLOTS:
+        /**
+         * Call this method when the runners should be prepared for a query session.
+         * Call matchSessionComplete when the query session is finished for the time
+         * being.
+         * @since 4.4
+         * @see matchSessionComplete
+         */
+        void setupMatchSession();
+
+        /**
+         * Call this method when the query session is finished for the time
+         * being.
+         * @since 4.4
+         * @see prepareForMatchSession
+         */
+        void matchSessionComplete();
+
         /**
          * Launch a query, this will create threads and return inmediately.
          * When the information will be available can be known using the