1 /*

     2  *    Copyright 2007-2008 Intel Corporation

     3  * 

     4  *    Licensed under the Apache License, Version 2.0 (the "License");

     5  *    you may not use this file except in compliance with the License.

     6  *    You may obtain a copy of the License at

     7  * 

     8  *        http://www.apache.org/licenses/LICENSE-2.0

     9  * 

    10  *    Unless required by applicable law or agreed to in writing, software

    11  *    distributed under the License is distributed on an "AS IS" BASIS,

    12  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

    13  *    See the License for the specific language governing permissions and

    14  *    limitations under the License.

    15  */

    16 

    17 #ifndef _BUNDLEINFOCACHE_H_

    18 #define _BUNDLEINFOCACHE_H_

    19 

    20 #include <oasys/debug/Logger.h>

    21 #include <oasys/util/Cache.h>

    22 #include <oasys/util/CacheCapacityHelper.h>

    23 #include "Bundle.h"

    24 #include "GbofId.h"

    25 

    26 namespace dtn {

    27 

    28 /**

    29  * Utility class for maintain a cache of recently received bundles,

    30  * indexed by GbofId. Used for routers to detect redundant BundleInfos

    31  * and to avoid duplicate deliveries to registrations.

    32  */

    33 class BundleInfoCache {

    34 public:

    35     /**

    36      * Constructor that takes the logpath and the number of entries to

    37      * maintain in the cache.

    38      */

    39     BundleInfoCache(const std::string& logpath, size_t capacity);

    40     

    41     /**

    42      * Try to add the bundle to the cache. If it already exists in the

    43      * cache, adding it again fails, and the method returns false.

    44      */

    45     bool add_entry(const Bundle* bundle, const EndpointID& prevhop);

    46 

    47     /**

    48      * Check if the given bundle is in the cache, returning the EID of

    49      * the node from which it arrived (if known).

    50      */

    51     bool lookup(const Bundle* bundle, EndpointID* prevhop);

    52 

    53     /**

    54      * Flush the cache.

    55      */

    56     void evict_all();

    57 

    58 protected:

    59     typedef oasys::CacheCapacityHelper<GbofId, EndpointID> CacheCapacityHelper;

    60     typedef oasys::Cache<GbofId, EndpointID, CacheCapacityHelper> Cache;

    61     Cache cache_;

    62 };

    63 

    64 } // namespace dtn

    65 

    66 

    67 #endif /* _BUNDLEINFOCACHE_H_ */