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Diffstat (limited to 'kdecore/klockfile.h')
-rw-r--r-- | kdecore/klockfile.h | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/kdecore/klockfile.h b/kdecore/klockfile.h new file mode 100644 index 000000000..b48d09926 --- /dev/null +++ b/kdecore/klockfile.h @@ -0,0 +1,123 @@ +/* + This file is part of the KDE libraries + Copyright (c) 2004 Waldo Bastian <bastian@kde.org> + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License version 2 as published by the Free Software Foundation. + + 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public License + along with this library; see the file COPYING.LIB. If not, write to + the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, + Boston, MA 02110-1301, USA. +*/ + +#ifndef _KLOCKFILE_H_ +#define _KLOCKFILE_H_ + +#include <qstring.h> +#include <qdatetime.h> + +#include <ksharedptr.h> +/** + * The KLockFile class provides NFS safe lockfiles. + * + * @author Waldo Bastian <bastian@kde.org> + * @since 3.3 + */ +class KDECORE_EXPORT KLockFile : public KShared +{ +public: + typedef KSharedPtr<KLockFile> Ptr; + + KLockFile(const QString &file); + + /** + * Destroys the object, releasing the lock if held + **/ + ~KLockFile(); + + /** + * Possible return values of the lock function. + */ + enum LockResult { + /** + * Lock was acquired successfully + */ + LockOK = 0, + + /** + * The lock could not be acquired because it is held by another process + */ + LockFail, + + /** + * The lock could not be acquired due to an error + */ + LockError, + + /** + * A stale lock has been detected + */ + LockStale + }; + + enum LockOptions { + /** + * Return immediately, do not wait for the lock to become available + */ + LockNoBlock = 1, + + /** + * Automatically remove a lock when a lock is detected that is stale + * for more than staleTime() seconds. + */ + LockForce = 2 + }; + + /** + * Attempt to acquire the lock + * + * @param options A set of @ref LockOptions OR'ed together. + */ + LockResult lock(int options=0); + + /** + * Returns whether the lock is held or not + */ + bool isLocked() const; + + /** + * Release the lock + */ + void unlock(); + + /** + * Return the time in seconds after which a lock is considered stale + * The default is 30. + */ + int staleTime() const; + + /** + * Set the time in seconds after which a lock is considered stale + */ + void setStaleTime(int _staleTime); + + /** + * Returns the pid, hostname and appname of the process holding + * the lock after the lock functon has returned with LockStale. + * @returns false if the pid and hostname could not be determined + */ + bool getLockInfo(int &pid, QString &hostname, QString &appname); + +private: + class KLockFilePrivate; + KLockFilePrivate *d; +}; + +#endif |