2 * Licensed to the University Corporation for Advanced Internet
3 * Development, Inc. (UCAID) under one or more contributor license
4 * agreements. See the NOTICE file distributed with this work for
5 * additional information regarding copyright ownership.
7 * UCAID licenses this file to you under the Apache License,
8 * Version 2.0 (the "License"); you may not use this file except
9 * in compliance with the License. You may obtain a copy of the
12 * http://www.apache.org/licenses/LICENSE-2.0
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
17 * either express or implied. See the License for the specific
18 * language governing permissions and limitations under the License.
22 * @file xmltooling/Lockable.h
24 * Locking abstraction.
27 #ifndef __xmltooling_lockable_h__
28 #define __xmltooling_lockable_h__
30 #include <xmltooling/base.h>
32 namespace xmltooling {
35 * Abstract mixin interface for interfaces that support locking
37 class XMLTOOL_API Lockable
45 * Lock the associated object for exclusive access.
47 * @return a pointer to the object being locked
49 virtual Lockable* lock()=0;
52 * Unlock the associated object from exclusive access.
54 virtual void unlock()=0;
58 * RAII wrapper for lockable objects to ensure lock release
60 class XMLTOOL_API Locker
62 MAKE_NONCOPYABLE(Locker);
65 * Optionally locks an object and stores it for later release.
67 * @param lockee pointer to an object to hold, and optionally lock
68 * @param lock true iff object is not yet locked
70 Locker(Lockable* lockee=nullptr, bool lock=true);
73 * Optionally locks an object and stores it for later release.
74 * If an object is already held, it is unlocked and detached.
76 * @param lockee pointer to an object to hold, and optionally lock
77 * @param lock true iff object is not yet locked
79 void assign(Lockable* lockee=nullptr, bool lock=true);
82 * Destructor releases lock on held pointer, if any.
92 #endif /* __xmltooling_lockable_h__ */