LockWatcher: Keep an eye on Windows file locks (#4758)

When a conflict-rename or a temporary-rename fails, notify the
LockWatcher. It'll regularly check whether the file has become
accesible again. When it has, another sync is triggered.

owncloud/enterprise#1288

1 files changed, 51 insertions, 0 deletions

diff --git a/src/gui/lockwatcher.cpp b/src/gui/lockwatcher.cpp
new file mode 100644
index 000000000..7b1247990
--- /dev/null
+++ b/src/gui/lockwatcher.cpp
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) by Christian Kamm <mail@ckamm.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "lockwatcher.h"
+#include "filesystem.h"
+
+#include <QTimer>
+
+using namespace OCC;
+
+static const int check_frequency = 20 * 1000; // ms
+
+LockWatcher::LockWatcher(QObject* parent)
+    : QObject(parent)
+{
+    connect(&_timer, SIGNAL(timeout()),
+            SLOT(checkFiles()));
+    _timer.start(check_frequency);
+}
+
+void LockWatcher::addFile(const QString& path)
+{
+    _watchedPaths.insert(path);
+}
+
+void LockWatcher::checkFiles()
+{
+    QSet<QString> unlocked;
+
+    foreach (const QString& path, _watchedPaths) {
+        if (!FileSystem::isFileLocked(path)) {
+            emit fileUnlocked(path);
+            unlocked.insert(path);
+        }
+    }
+
+    // Doing it this way instead of with a QMutableSetIterator
+    // ensures that calling back into addFile from connected
+    // slots isn't a problem.
+    _watchedPaths.subtract(unlocked);
+}