allow runners to signal that matching should be suspended for them

svn path=/trunk/KDE/kdelibs/; revision=1171157

abstractrunner.cpp

@@ -125,6 +125,10 @@ void AbstractRunner::performMatch(Plasma::RunnerContext &localContext)
     static const int reasonableRunTime = 1500;
     static const int fastEnoughTime = 250;
 
+    if (d->suspendMatching) {
+        return;
+    }
+
     QTime time;
     time.restart();
 
@@ -360,6 +364,21 @@ DataEngine *AbstractRunner::dataEngine(const QString &name) const
     return d->dataEngine(name);
 }
 
+bool AbstractRunner::isMatchingSuspended() const
+{
+    return d->suspendMatching;
+}
+
+void AbstractRunner::suspendMatching(bool suspend)
+{
+    if (d->suspendMatching == suspend) {
+        return;
+    }
+
+    d->suspendMatching = suspend;
+    emit matchingSuspended(suspend);
+}
+
 AbstractRunnerPrivate::AbstractRunnerPrivate(AbstractRunner *r)
     : priority(AbstractRunner::NormalPriority),
       speed(AbstractRunner::NormalSpeed),
@@ -368,8 +387,9 @@ AbstractRunnerPrivate::AbstractRunnerPrivate(AbstractRunner *r)
       runner(r),
       fastRuns(0),
       package(0),
+      defaultSyntax(0),
       hasRunOptions(false),
-      defaultSyntax(0)
+      suspendMatching(false)
 {
 }
 

abstractrunner.h

@@ -63,6 +63,7 @@ class AbstractRunnerPrivate;
 class PLASMA_EXPORT AbstractRunner : public QObject
 {
     Q_OBJECT
+    Q_PROPERTY(bool matchingSuspended READ isMatchingSuspended WRITE suspendMatching NOTIFY matchingSuspended)
 
     public:
         /** Specifies a nominal speed for the runner */
@@ -257,6 +258,13 @@ class PLASMA_EXPORT AbstractRunner : public QObject
          */
         RunnerSyntax *defaultSyntax() const;
 
+        /**
+         * @return true if the runner is currently busy with non-interuptable work, signaling that
+         * new threads should not be created for it at this time
+         * @since 4.6
+         */
+        bool isMatchingSuspended() const;
+
     Q_SIGNALS:
         /**
          * This signal is emitted when matching is about to commence, giving runners
@@ -277,6 +285,13 @@ class PLASMA_EXPORT AbstractRunner : public QObject
          */
         void teardown();
 
+        /**
+         * Emitted when the runner enters or exits match suspension
+         * @see matchingSuspended
+         * @since 4.6
+         */
+        void matchingSuspended(bool suspended);
+
     protected:
         friend class RunnerManager;
         friend class RunnerManagerPrivate;
@@ -286,6 +301,12 @@ class PLASMA_EXPORT AbstractRunner : public QObject
 
         AbstractRunner(QObject *parent, const QVariantList &args);
 
+        /**
+         * Sets whether or not the runner is available for match requests. Useful to
+         * prevent more thread spawning when the thread is in a busy state.
+         */
+        void suspendMatching(bool suspend);
+
         /**
          * Provides access to the runner's configuration object.
          */

private/abstractrunner_p.h

@@ -46,12 +46,13 @@ public:
     KPluginInfo runnerDescription;
     AbstractRunner *runner;
     int fastRuns;
+    QReadWriteLock speedLock;
     Package *package;
     QHash<QString, QAction*> actions;
     QList<RunnerSyntax> syntaxes;
-    bool hasRunOptions;
-    QReadWriteLock speedLock;
     RunnerSyntax *defaultSyntax;
+    bool hasRunOptions : 1;
+    bool suspendMatching : 1;
 };
 
 } // namespace Plasma

runnermanager.cpp

@@ -263,6 +263,7 @@ public:
 
         if (runner) {
             kDebug() << "================= loading runner:" << service->name() << "=================";
+            QObject::connect(runner, SIGNAL(matchingSuspended(bool)), q, SLOT(runnerMatchingSuspended(bool)));
             QMetaObject::invokeMethod(runner, "init");
         }
 
@@ -352,6 +353,32 @@ public:
         QObject::connect(dummy, SIGNAL(done(ThreadWeaver::Job*)), dummy, SLOT(deleteLater()));
     }
 
+    void runnerMatchingSuspended(bool suspended)
+    {
+        if (suspended || !prepped || teardownRequested) {
+            return;
+        }
+
+        AbstractRunner *runner = qobject_cast<AbstractRunner *>(q->sender());
+
+        if (runner) {
+            startJob(runner);
+        }
+    }
+
+    void startJob(AbstractRunner *runner)
+    {
+        if ((runner->ignoredTypes() & context.type()) == 0) {
+            FindMatchesJob *job = new FindMatchesJob(runner, &context, Weaver::instance());
+            QObject::connect(job, SIGNAL(done(ThreadWeaver::Job*)), q, SLOT(jobDone(ThreadWeaver::Job*)));
+            if (runner->speed() == AbstractRunner::SlowSpeed) {
+                job->setDelayTimer(&delayTimer);
+            }
+            Weaver::instance()->enqueue(job);
+            searchJobs.insert(job);
+        }
+    }
+
     // Delay in ms before slow runners are allowed to run
     static const int slowRunDelay = 400;
 
@@ -445,6 +472,7 @@ void RunnerManager::loadRunner(const QString &path)
 {
     if (!d->runners.contains(path)) {
         AbstractRunner *runner = new AbstractRunner(this, path);
+        connect(runner, SIGNAL(matchingSuspended(bool)), this, SLOT(runnerMatchingSuspended(bool)));
         d->runners.insert(path, runner);
     }
 }
@@ -580,12 +608,12 @@ QMimeData * RunnerManager::mimeDataForMatch(const QString &id) const
 QMimeData * RunnerManager::mimeDataForMatch(const QueryMatch &match) const
 {
     AbstractRunner *runner = match.runner();
-    QMimeData * mimeData;
+    QMimeData *mimeData;
     if (runner && QMetaObject::invokeMethod(
             runner,
             "mimeDataForMatch", Qt::DirectConnection,
             Q_RETURN_ARG(QMimeData*, mimeData),
-            Q_ARG(const Plasma::QueryMatch *, & match)
+            Q_ARG(const Plasma::QueryMatch *, &match)
     )) {
         return mimeData;
     }
@@ -689,16 +717,11 @@ void RunnerManager::launchQuery(const QString &untrimmedTerm, const QString &run
     }
 
     foreach (Plasma::AbstractRunner *r, runable) {
-        if ((r->ignoredTypes() & d->context.type()) == 0) {
-//            kDebug() << "launching" << r->name();
-            FindMatchesJob *job = new FindMatchesJob(r, &d->context, Weaver::instance());
-            connect(job, SIGNAL(done(ThreadWeaver::Job*)), this, SLOT(jobDone(ThreadWeaver::Job*)));
-            if (r->speed() == AbstractRunner::SlowSpeed) {
-                job->setDelayTimer(&d->delayTimer);
-            }
-            Weaver::instance()->enqueue(job);
-            d->searchJobs.insert(job);
+        if (r->isMatchingSuspended()) {
+            continue;
         }
+
+        d->startJob(r);
     }
 
     // Start timer to unblock slow runners

runnermanager.h

@@ -290,6 +290,7 @@ class PLASMA_EXPORT RunnerManager : public QObject
         Q_PRIVATE_SLOT(d, void matchesChanged())
         Q_PRIVATE_SLOT(d, void jobDone(ThreadWeaver::Job*))
         Q_PRIVATE_SLOT(d, void unblockJobs())
+        Q_PRIVATE_SLOT(d, void runnerMatchingSuspended(bool))
 
         RunnerManagerPrivate * const d;