Author: tabish
Date: Fri Jan 30 18:44:02 2009
New Revision: 739372
URL: http://svn.apache.org/viewvc?rev=739372&view=rev
Log:
Adds an AtomicReference to decaf's atomic package to allow for safe pointer
exchange.
Added:
activemq/activemq-cpp/trunk/src/main/decaf/util/concurrent/atomic/AtomicReference.h
(with props)
Added:
activemq/activemq-cpp/trunk/src/main/decaf/util/concurrent/atomic/AtomicReference.h
URL:
http://svn.apache.org/viewvc/activemq/activemq-cpp/trunk/src/main/decaf/util/concurrent/atomic/AtomicReference.h?rev=739372&view=auto
==============================================================================
---
activemq/activemq-cpp/trunk/src/main/decaf/util/concurrent/atomic/AtomicReference.h
(added)
+++
activemq/activemq-cpp/trunk/src/main/decaf/util/concurrent/atomic/AtomicReference.h
Fri Jan 30 18:44:02 2009
@@ -0,0 +1,100 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _DECAF_UTIL_CONCURRENT_ATOMIC_ATOMICREFERENCE_H_
+#define _DECAF_UTIL_CONCURRENT_ATOMIC_ATOMICREFERENCE_H_
+
+#include <decaf/util/Config.h>
+#include <decaf/lang/Long.h>
+#include <apr_atomic.h>
+
+namespace decaf {
+namespace util {
+namespace concurrent {
+namespace atomic {
+
+ /**
+ * An Pointer reference that may be updated atomically.
+ */
+ template< typename T >
+ class DECAF_API AtomicReference {
+
+ volatile void* value;
+
+ public:
+
+ AtomicReference() : value( NULL ) {}
+ AtomicReference( T* value ) : value( (void*)value ) {}
+
+ virtual ~AtomicReference() {}
+
+ /**
+ * Gets the Current Value.
+ * @return the current value of this Reference.
+ */
+ T* get() const {
+ return (T*)value;
+ }
+
+ /**
+ * Sets the Current value of this Reference.
+ *
+ * @param newValue
+ * The new Value of this Reference.
+ */
+ void set( T* newValue ) {
+ apr_atomic_xchgptr( &this->value, (void*)newValue );
+ }
+
+ /**
+ * Atomically sets the value to the given updated value if the current
value ==
+ * the expected value.
+ *
+ * @param expect - the expected value
+ * @param update - the new value
+ *
+ * @return true if successful. False return indicates that the actual
value was
+ * not equal to the expected value.
+ */
+ bool compareAndSet( T* expect, T* update ) {
+ return apr_atomic_casptr( &this->value, (void*)update,
(void*)expect ) == (void*)expect;
+ }
+
+ /**
+ * Atomically sets to the given value and returns the old value.
+ *
+ * @param newValue- the new value
+ *
+ * @return the previous value.
+ */
+ T* getAndSet( T* newValue ) {
+ return (T*)apr_atomic_xchgptr( &this->value, (void*)newValue );
+ }
+
+ /**
+ * Returns the String representation of the current value.
+ * @returns string representation of the current value.
+ */
+ std::string toString() const {
+ return decaf::lang::Long::toString( (long long)this->value );
+ }
+
+ };
+
+}}}}
+
+#endif /*_DECAF_UTIL_CONCURRENT_ATOMIC_ATOMICREFERENCE_H_*/
Propchange:
activemq/activemq-cpp/trunk/src/main/decaf/util/concurrent/atomic/AtomicReference.h
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svn:eol-style = native
