third_party_nghttp2/lib/spdylay_pq.h
2012-03-15 23:06:28 +09:00

100 lines
2.8 KiB
C

/*
* Spdylay - SPDY Library
*
* Copyright (c) 2012 Tatsuhiro Tsujikawa
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef SPDYLAY_PQ_H
#define SPDYLAY_PQ_H
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif /* HAVE_CONFIG_H */
#include <spdylay/spdylay.h>
#include "spdylay_int.h"
/* Implementation of priority queue */
typedef struct {
/* The pointer to the pointer to the item stored */
void **q;
/* The number of items sotred */
size_t length;
/* The maximum number of items this pq can store. This is
automatically extended when length is reached to this value. */
size_t capacity;
/* The compare function between items */
spdylay_compar compar;
} spdylay_pq;
/*
* Initializes priority queue |pq| with compare function |cmp|.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* SPDYLAY_ERR_NOMEM
* Out of memory.
*/
int spdylay_pq_init(spdylay_pq *pq, spdylay_compar cmp);
/*
* Deallocates any resources allocated for |pq|. The stored items are
* not freed by this function.
*/
void spdylay_pq_free(spdylay_pq *pq);
/*
* Adds |item| to the priority queue |pq|.
*
* This function returns 0 if it succeds, or one of the following
* negative error codes:
*
* SPDYLAY_ERR_NOMEM
* Out of memory.
*/
int spdylay_pq_push(spdylay_pq *pq, void *item);
/*
* Returns item at the top of the queue |pq|. If the queue is empty,
* this function returns NULL.
*/
void* spdylay_pq_top(spdylay_pq *pq);
/*
* Pops item at the top of the queue |pq|. The popped item is not
* freed by this function.
*/
void spdylay_pq_pop(spdylay_pq *pq);
/*
* Returns nonzero if the queue |pq| is empty.
*/
int spdylay_pq_empty(spdylay_pq *pq);
/*
* Returns the number of items in the queue |pq|.
*/
size_t spdylay_pq_size(spdylay_pq *pq);
#endif /* SPDYLAY_PQ_H */