| /* |
| * nghttp2 - HTTP/2 C 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 NGHTTP2_PQ_H |
| #define NGHTTP2_PQ_H |
| |
| #ifdef HAVE_CONFIG_H |
| # include <config.h> |
| #endif /* HAVE_CONFIG_H */ |
| |
| #include <nghttp2/nghttp2.h> |
| #include "nghttp2_int.h" |
| #include "nghttp2_mem.h" |
| |
| /* Implementation of priority queue */ |
| |
| typedef struct { |
| size_t index; |
| } nghttp2_pq_entry; |
| |
| typedef struct { |
| /* The pointer to the pointer to the item stored */ |
| nghttp2_pq_entry **q; |
| /* Memory allocator */ |
| nghttp2_mem *mem; |
| /* The number of items stored */ |
| 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 less function between items */ |
| nghttp2_less less; |
| } nghttp2_pq; |
| |
| /* |
| * Initializes priority queue |pq| with compare function |cmp|. |
| */ |
| void nghttp2_pq_init(nghttp2_pq *pq, nghttp2_less less, nghttp2_mem *mem); |
| |
| /* |
| * Deallocates any resources allocated for |pq|. The stored items are |
| * not freed by this function. |
| */ |
| void nghttp2_pq_free(nghttp2_pq *pq); |
| |
| /* |
| * Adds |item| to the priority queue |pq|. |
| * |
| * This function returns 0 if it succeeds, or one of the following |
| * negative error codes: |
| * |
| * NGHTTP2_ERR_NOMEM |
| * Out of memory. |
| */ |
| int nghttp2_pq_push(nghttp2_pq *pq, nghttp2_pq_entry *item); |
| |
| /* |
| * Returns item at the top of the queue |pq|. If the queue is empty, |
| * this function returns NULL. |
| */ |
| nghttp2_pq_entry *nghttp2_pq_top(nghttp2_pq *pq); |
| |
| /* |
| * Pops item at the top of the queue |pq|. The popped item is not |
| * freed by this function. |
| */ |
| void nghttp2_pq_pop(nghttp2_pq *pq); |
| |
| /* |
| * Returns nonzero if the queue |pq| is empty. |
| */ |
| int nghttp2_pq_empty(nghttp2_pq *pq); |
| |
| /* |
| * Returns the number of items in the queue |pq|. |
| */ |
| size_t nghttp2_pq_size(nghttp2_pq *pq); |
| |
| typedef int (*nghttp2_pq_item_cb)(nghttp2_pq_entry *item, void *arg); |
| |
| /* |
| * Updates each item in |pq| using function |fun| and re-construct |
| * priority queue. The |fun| must return non-zero if it modifies the |
| * item in a way that it affects ordering in the priority queue. The |
| * |arg| is passed to the 2nd parameter of |fun|. |
| */ |
| void nghttp2_pq_update(nghttp2_pq *pq, nghttp2_pq_item_cb fun, void *arg); |
| |
| /* |
| * Applies |fun| to each item in |pq|. The |arg| is passed as arg |
| * parameter to callback function. This function must not change the |
| * ordering key. If the return value from callback is nonzero, this |
| * function returns 1 immediately without iterating remaining items. |
| * Otherwise this function returns 0. |
| */ |
| int nghttp2_pq_each(nghttp2_pq *pq, nghttp2_pq_item_cb fun, void *arg); |
| |
| /* |
| * Removes |item| from priority queue. |
| */ |
| void nghttp2_pq_remove(nghttp2_pq *pq, nghttp2_pq_entry *item); |
| |
| #endif /* NGHTTP2_PQ_H */ |