Improved temp_folder() function + we will now clean-up the TEMP folder on application...

[mutilities/MUtilities.git] / src / DirLocker.h

diff --git a/src/DirLocker.h b/src/DirLocker.h
new file mode 100644 (file)
index 0000000..f4a683f
--- /dev/null
+++ b/src/DirLocker.h
@@ -0,0 +1,112 @@
+///////////////////////////////////////////////////////////////////////////////
+// MuldeR's Utilities for Qt
+// Copyright (C) 2004-2014 LoRd_MuldeR <MuldeR2@GMX.de>
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+//
+// This library 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
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+//
+// http://www.gnu.org/licenses/lgpl-2.1.txt
+//////////////////////////////////////////////////////////////////////////////////
+
+#pragma once
+
+//MUtils
+#include <MUtils/Global.h>
+
+//StdLib
+#include <stdexcept>
+
+//Qt
+#include <QString>
+#include <QFile>
+
+///////////////////////////////////////////////////////////////////////////////
+// Directory Locker
+///////////////////////////////////////////////////////////////////////////////
+
+namespace MUtils
+{
+       namespace Internal
+       {
+               class DirLockException : public std::runtime_error
+               {
+               public:
+                       DirLockException(const char *const message)
+                       :
+                               std::runtime_error(message)
+                       {
+                       }
+               };
+
+               class DirLock
+               {
+               public:
+                       DirLock(const QString dirPath)
+                       :
+                               m_dirPath(dirPath)
+                       {
+                               if(m_dirPath.isEmpty())
+                               {
+                                       throw DirLockException("Path must not be empty!");
+                               }
+                               const QByteArray testData = QByteArray(TEST_DATA);
+                               bool okay = false;
+                               for(int i = 0; i < 32; i++)
+                               {
+                                       m_lockFile.reset(new QFile(QString("%1/~%2.lck").arg(m_dirPath, MUtils::rand_str())));
+                                       if(m_lockFile->open(QIODevice::WriteOnly | QIODevice::Truncate))
+                                       {
+                                               if(m_lockFile->write(testData) >= testData.size())
+                                               {
+                                                       okay = true;
+                                                       break;
+                                               }
+                                               m_lockFile->remove();
+                                       }
+                               }
+                               if(!okay)
+                               {
+                                       throw DirLockException("Locking has failed!");
+                               }
+                       }
+
+                       ~DirLock(void)
+                       {
+                               if(!m_lockFile.isNull())
+                               {
+                                       m_lockFile->remove();
+                               }
+                               for(int i = 0; i < 8; i++)
+                               {
+                                       if(MUtils::remove_directory(m_dirPath))
+                                       {
+                                               break;
+                                       }
+                               }
+                       }
+
+                       inline const QString &path(void) const
+                       {
+                               return m_dirPath;
+                       }
+
+               private:
+                       static const char *const TEST_DATA;
+                       const QString m_dirPath;
+                       QScopedPointer<QFile> m_lockFile;
+               };
+
+               const char *const DirLock::TEST_DATA = "7QtDxPWotHGQYv1xHyQHFKjTB5u5VYKHE20NMDAgLRYoy16CZN7mEYijbjCJpORnoBbtHCzqyy1a6BLCMMiTUZpLzgjg4qnN505egUBqk3wMhPsYjFpkng9i37mWd1iF";
+       }
+}