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/* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership.
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* The ASF licenses this file to You under the Apache License, Version 2.0
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* (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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#include "apr_general.h"
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#include "mod_cache.h"
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#include "cache_hash.h"
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#include "cache_pqueue.h"
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#include "cache_cache.h"
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struct cache_cache_t {
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apr_size_t current_size;
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cache_pqueue_set_priority set_pri;
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cache_pqueue_get_priority get_pri;
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cache_cache_inc_frequency *inc_entry;
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cache_cache_get_size *size_entry;
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cache_cache_get_key *key_entry;
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cache_cache_free *free_entry;
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CACHE_DECLARE(cache_cache_t *)cache_init(int max_entries,
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cache_pqueue_get_priority get_pri,
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cache_pqueue_set_priority set_pri,
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cache_pqueue_getpos get_pos,
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cache_pqueue_setpos set_pos,
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cache_cache_inc_frequency *inc_entry,
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cache_cache_get_size *size_entry,
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cache_cache_get_key* key_entry,
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cache_cache_free *free_entry)
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tmp = malloc(sizeof(cache_cache_t));
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tmp->max_entries = max_entries;
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tmp->max_size = max_size;
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tmp->current_size = 0;
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tmp->total_purges = 0;
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tmp->get_pri = get_pri;
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tmp->set_pri = set_pri;
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tmp->inc_entry = inc_entry;
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tmp->size_entry = size_entry;
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tmp->key_entry = key_entry;
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tmp->free_entry = free_entry;
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tmp->ht = cache_hash_make(max_entries);
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tmp->pq = cache_pq_init(max_entries, get_pri, get_pos, set_pos);
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CACHE_DECLARE(void) cache_free(cache_cache_t *c)
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cache_hash_free(c->ht);
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CACHE_DECLARE(void*) cache_find(cache_cache_t* c, const char *key)
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e = cache_hash_get(c->ht, key, CACHE_HASH_KEY_STRING);
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CACHE_DECLARE(void) cache_update(cache_cache_t* c, void *entry)
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old_priority = c->set_pri(c->queue_clock, entry);
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new_priority = c->set_pri(c->queue_clock, entry);
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cache_pq_change_priority(c->pq, old_priority, new_priority, entry);
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CACHE_DECLARE(void) cache_insert(cache_cache_t* c, void *entry)
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void *ejected = NULL;
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c->set_pri(c->queue_clock, entry);
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/* FIX: check if priority of bottom item is greater than inserted one */
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while ((cache_pq_size(c->pq) >= c->max_entries) ||
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((c->current_size + c->size_entry(entry)) > c->max_size)) {
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ejected = cache_pq_pop(c->pq);
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/* FIX: If ejected is NULL, we'll segfault here */
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priority = c->get_pri(ejected);
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if (c->queue_clock > priority)
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c->queue_clock = priority;
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cache_hash_set(c->ht,
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c->key_entry(ejected),
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CACHE_HASH_KEY_STRING,
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ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, NULL, "Cache Purge of %s",c->key_entry(ejected));
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c->current_size -= c->size_entry(ejected);
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c->free_entry(ejected);
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c->current_size += c->size_entry(entry);
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cache_pq_insert(c->pq, entry);
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cache_hash_set(c->ht, c->key_entry(entry), CACHE_HASH_KEY_STRING, entry);
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CACHE_DECLARE(void *) cache_pop(cache_cache_t *c)
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entry = cache_pq_pop(c->pq);
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c->current_size -= c->size_entry(entry);
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cache_hash_set(c->ht, c->key_entry(entry), CACHE_HASH_KEY_STRING, NULL);
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CACHE_DECLARE(apr_status_t) cache_remove(cache_cache_t *c, void *entry)
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apr_size_t entry_size = c->size_entry(entry);
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rc = cache_pq_remove(c->pq, entry);
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if (rc != APR_SUCCESS)
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cache_hash_set(c->ht, c->key_entry(entry), CACHE_HASH_KEY_STRING, NULL);
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c->current_size -= entry_size;