QFileInfoGatherer: Make it possible to turn off file watching

Add a boolean watch property and delay-create the file system watcher
in watchPaths(). De-inline the watchedFiles(), watchedDirectories(),
watchPaths(), unwatchPaths() helpers and a check for the watcher.

Task-number: QTBUG-76493
Change-Id: Ie02ac496c8c0246be62bc67ff7e0fcdb990b5ca6
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

1 files changed, 13 insertions, 7 deletions

diff --git a/src/widgets/dialogs/qfileinfogatherer_p.h b/src/widgets/dialogs/qfileinfogatherer_p.h
index 829c620c1e..3d30a98d04 100644
--- a/src/widgets/dialogs/qfileinfogatherer_p.h
+++ b/src/widgets/dialogs/qfileinfogatherer_p.h
@@ -169,12 +169,13 @@ public:
     explicit QFileInfoGatherer(QObject *parent = nullptr);
     ~QFileInfoGatherer();
 
-#if QT_CONFIG(filesystemwatcher) && defined(Q_OS_WIN)
-    QStringList watchedFiles() const            { return watcher->files(); }
-    QStringList watchedDirectories() const      { return watcher->directories(); }
-    void watchPaths(const QStringList &paths)   { watcher->addPaths(paths); }
-    void unwatchPaths(const QStringList &paths) { watcher->removePaths(paths); }
-#endif // filesystemwatcher && Q_OS_WIN
+    QStringList watchedFiles() const;
+    QStringList watchedDirectories() const;
+    void watchPaths(const QStringList &paths);
+    void unwatchPaths(const QStringList &paths);
+
+    bool isWatching() const;
+    void setWatching(bool v);
 
     // only callable from this->thread():
     void clear();
@@ -201,6 +202,8 @@ private:
     void fetch(const QFileInfo &info, QElapsedTimer &base, bool &firstTime, QVector<QPair<QString, QFileInfo> > &updatedFiles, const QString &path);
 
 private:
+    void createWatcher();
+
     mutable QMutex mutex;
     // begin protected by mutex
     QWaitCondition condition;
@@ -210,13 +213,16 @@ private:
     QAtomicInt abort;
 
 #if QT_CONFIG(filesystemwatcher)
-    QFileSystemWatcher *watcher = nullptr;
+    QFileSystemWatcher *m_watcher = nullptr;
 #endif
     QFileIconProvider *m_iconProvider; // not accessed by run()
     QFileIconProvider defaultProvider;
 #ifdef Q_OS_WIN
     bool m_resolveSymlinks = true; // not accessed by run()
 #endif
+#if QT_CONFIG(filesystemwatcher)
+    bool m_watching = true;
+#endif
 };
 
 QT_END_NAMESPACE