diff options
Diffstat (limited to 'metis/ccnx/forwarder/metis/content_store/metis_TimeOrderedList.c')
-rw-r--r-- | metis/ccnx/forwarder/metis/content_store/metis_TimeOrderedList.c | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/metis/ccnx/forwarder/metis/content_store/metis_TimeOrderedList.c b/metis/ccnx/forwarder/metis/content_store/metis_TimeOrderedList.c new file mode 100644 index 00000000..55054c59 --- /dev/null +++ b/metis/ccnx/forwarder/metis/content_store/metis_TimeOrderedList.c @@ -0,0 +1,103 @@ +/* + * Copyright (c) 2017 Cisco and/or its affiliates. + * Licensed 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. + */ + + +#include <config.h> +#include <LongBow/runtime.h> + +#include <ccnx/forwarder/metis/content_store/metis_TimeOrderedList.h> + +#include <parc/algol/parc_Object.h> +#include <parc/algol/parc_TreeRedBlack.h> + +/** + * A list of MetisContentStoreEntrys, kept in sorted order by time. The ordering is calculated by a + * key compare function (e.g. {@link MetisTimeOrderList_KeyCompare}), passed in. + * + * This container does not hold references to the objects that it contains. In other words, it does not Acquire() + * the MetisMessages that are placed in it. That reference count is managed by the owning ContentStore. This is + * purely an index, and provides an easy to way index MetisMessages based on a specified time value. Typically, + * that would be their Recommended Cache Time, or Expiration Time. + * + * It maintains a tree, sorted by the time values passed in to the Add() function. It does not manage capacity, + * and can grow uncontrollably if the owning ContentStore does not manage it. Items are indexed first by time, then + * address of the MetisMessage (just as a distringuishing attribute). This allows us to store multiple items with + * the same expiration time. + */ + +struct metis_timeordered_list { + PARCTreeRedBlack *timeOrderedTree; +}; + +static void +_finalRelease(MetisTimeOrderedList **listP) +{ + MetisTimeOrderedList *list = *listP; + parcTreeRedBlack_Destroy(&list->timeOrderedTree); +} + +parcObject_ExtendPARCObject(MetisTimeOrderedList, _finalRelease, NULL, NULL, NULL, NULL, NULL, NULL); + +parcObject_ImplementAcquire(metisTimeOrderedList, MetisTimeOrderedList); + +parcObject_ImplementRelease(metisTimeOrderedList, MetisTimeOrderedList); + + +MetisTimeOrderedList * +metisTimeOrderedList_Create(MetisTimeOrderList_KeyCompare *keyCompareFunction) +{ + MetisTimeOrderedList *result = parcObject_CreateInstance(MetisTimeOrderedList); + if (NULL != result) { + result->timeOrderedTree = parcTreeRedBlack_Create(keyCompareFunction, // keyCompare + NULL, // keyFree + NULL, // keyCopy + NULL, // valueEquals + NULL, // valueFree + NULL); // valueCopy + } + return result; +} + +void +metisTimeOrderedList_Add(MetisTimeOrderedList *list, MetisContentStoreEntry *entry) +{ + parcTreeRedBlack_Insert(list->timeOrderedTree, entry, entry); +} + +MetisContentStoreEntry * +metisTimeOrderedList_GetOldest(MetisTimeOrderedList *list) +{ + return parcTreeRedBlack_FirstKey(list->timeOrderedTree); +} + +bool +metisTimeOrderedList_Remove(MetisTimeOrderedList *list, MetisContentStoreEntry *storeEntry) +{ + bool result = false; + + MetisContentStoreEntry *entry = (MetisContentStoreEntry *) parcTreeRedBlack_Remove(list->timeOrderedTree, storeEntry); + if (entry != NULL) { + result = true; + } + return result; +} + +size_t +metisTimeOrderedList_Length(MetisTimeOrderedList *list) +{ + return (size_t) parcTreeRedBlack_Size(list->timeOrderedTree); +} + + |