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Diffstat (limited to 'rubbos/app/httpd-2.0.64/modules/experimental/cache_pqueue.h')
| -rw-r--r-- | rubbos/app/httpd-2.0.64/modules/experimental/cache_pqueue.h | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/rubbos/app/httpd-2.0.64/modules/experimental/cache_pqueue.h b/rubbos/app/httpd-2.0.64/modules/experimental/cache_pqueue.h new file mode 100644 index 00000000..19709764 --- /dev/null +++ b/rubbos/app/httpd-2.0.64/modules/experimental/cache_pqueue.h @@ -0,0 +1,160 @@ +/* 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 CACHE_PQUEUE_H +#define CACHE_PQUEUE_H + +#include <apr.h> +#include <apr_errno.h> + +#if APR_HAVE_STDIO_H +#include <stdio.h> +#endif + +#ifdef __cplusplus +extern "C" { +#endif + +/** the cache priority queue handle */ +typedef struct cache_pqueue_t cache_pqueue_t; + +/** + * callback function to assign a priority for a element + * @param a the element + * @return the score (the lower the score the longer it is kept int the queue) + */ +typedef long (*cache_pqueue_set_priority)(long queue_clock, void *a); +typedef long (*cache_pqueue_get_priority)(void *a); + +/** callback function to get a position of a element */ +typedef apr_ssize_t (*cache_pqueue_getpos)(void *a); + +/** + * callback function to set a position of a element + * @param a the element + * @param pos the position to set it to + */ +typedef void (*cache_pqueue_setpos)(void *a, apr_ssize_t pos); + +/** debug callback function to print a entry */ +typedef void (*cache_pqueue_print_entry)(FILE *out, void *a); + +/** + * initialize the queue + * + * @param n the initial estimate of the number of queue items for which memory + * should be preallocated + * @param pri the callback function to run to assign a score to a element + * @param get the callback function to get the current element's position + * @param set the callback function to set the current element's position + * + * @Return the handle or NULL for insufficent memory + */ +cache_pqueue_t *cache_pq_init(apr_ssize_t n, + cache_pqueue_get_priority pri, + cache_pqueue_getpos get, + cache_pqueue_setpos set); +/** + * free all memory used by the queue + * @param q the queue + */ +void cache_pq_free(cache_pqueue_t *q); +/** + * return the size of the queue. + * @param q the queue + */ +apr_ssize_t cache_pq_size(cache_pqueue_t *q); + +/** + * insert an item into the queue. + * @param q the queue + * @param d the item + * @return APR_SUCCESS on success + */ +apr_status_t cache_pq_insert(cache_pqueue_t *q, void *d); + +/* + * move a existing entry to a different priority + * @param q the queue + * @param old the old priority + * @param d the entry + */ +void cache_pq_change_priority(cache_pqueue_t *q, + long old_priority, + long new_priority, + void *d); + +/** + * pop the highest-ranking item from the queue. + * @param p the queue + * @param d where to copy the entry to + * @return NULL on error, otherwise the entry + */ +void *cache_pq_pop(cache_pqueue_t *q); + +/** + * remove an item from the queue. + * @param p the queue + * @param d the entry + * @return APR_SUCCESS on success + */ +apr_status_t cache_pq_remove(cache_pqueue_t *q, void *d); + +/** + * access highest-ranking item without removing it. + * @param q the queue + * @param d the entry + * @return NULL on error, otherwise the entry + */ +void *cache_pq_peek(cache_pqueue_t *q); + +/** + * print the queue + * @internal + * DEBUG function only + * @param q the queue + * @param out the output handle + * @param the callback function to print the entry + */ +void cache_pq_print(cache_pqueue_t *q, + FILE *out, + cache_pqueue_print_entry print); + +/** + * dump the queue and it's internal structure + * @internal + * debug function only + * @param q the queue + * @param out the output handle + * @param the callback function to print the entry + */ +void cache_pq_dump(cache_pqueue_t *q, + FILE *out, + cache_pqueue_print_entry print); + +/** + * checks that the pq is in the right order, etc + * @internal + * debug function only + * @param q the queue + */ +int cache_pq_is_valid(cache_pqueue_t *q); + +#ifdef __cplusplus +} +#endif + +#endif /* !CACHE_PQUEUE_H */ |