1 /*

     2  *    Copyright 2004-2006 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 _GLOBAL_STORE_H_

    18 #define _GLOBAL_STORE_H_

    19 

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

    21 #include <oasys/debug/Log.h>

    22 #include <oasys/serialize/Serialize.h>

    23 

    24 // forward decl

    25 namespace oasys {

    26 template<typename _Type> class SingleTypeDurableTable;

    27 class DurableStore;

    28 class Mutex;

    29 class StorageConfig;

    30 }

    31 

    32 namespace dtn {

    33 

    34 class Globals;

    35 

    36 /**

    37  * Class for those elements of the router that need to be persistently

    38  * stored but are singleton global values. Examples include the

    39  * running sequence number for bundles and registrations, as well as

    40  * any other persistent configuration settings.

    41  */

    42 class GlobalStore : public oasys::Logger {

    43 public:

    44     static const u_int32_t CURRENT_VERSION;

    45     

    46     /**

    47      * Singleton instance accessor.

    48      */

    49     static GlobalStore* instance() {

    50         if (instance_ == NULL) {

    51             PANIC("GlobalStore::init not called yet");

    52         }

    53         return instance_;

    54     }

    55 

    56     /**

    57      * Boot time initializer

    58      *

    59      */

    60     static int init(const oasys::StorageConfig& cfg, 

    61                     oasys::DurableStore*        store);

    62 

    63     /**

    64      * Constructor.

    65      */

    66     GlobalStore();

    67 

    68     /**

    69      * Real initialization method.

    70      */

    71     int do_init(const oasys::StorageConfig& cfg, 

    72                 oasys::DurableStore*        store);

    73     

    74     /**

    75      * Return true if initialization has completed.

    76      */

    77     static bool initialized() { return (instance_ != NULL); }

    78     

    79     /**

    80      * Destructor.

    81      */

    82     ~GlobalStore();

    83 

    84     /**

    85      * Get a new bundle id, updating the value in the store

    86      *

    87      * (was db_update_bundle_id, db_restore_bundle_id)

    88      */

    89     u_int32_t next_bundleid();

    90     

    91     /**

    92      * Get a new unique registration id, updating the running value in

    93      * the persistent table.

    94      *

    95      * (was db_new_regID, db_update_registration_id,

    96      * db_retable_registration_id)

    97      */

    98     u_int32_t next_regid();

    99 

   100     /**

   101      * Load in the globals.

   102      */

   103     bool load();

   104 

   105     /**

   106      * Close (and flush) the data store.

   107      */

   108     void close();

   109 

   110 protected:

   111     /**

   112      * Update the globals in the store.

   113      */

   114     void update();

   115 

   116     /**

   117      * Calculate a digest of on-disk serialized objects.

   118      */

   119     void calc_digest(u_char* digest);

   120 

   121     bool loaded_;

   122     Globals* globals_;

   123     oasys::SingleTypeDurableTable<Globals>* store_;

   124 

   125     oasys::Mutex* lock_;

   126 

   127     static GlobalStore* instance_; ///< singleton instance

   128 };

   129 } // namespace dtn

   130 

   131 #endif /* _GLOBAL_STORE_H_ */