1/*
2 * nghttp2 - HTTP/2 C Library
3 *
4 * Copyright (c) 2012 Tatsuhiro Tsujikawa
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining
7 * a copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sublicense, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be
15 * included in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 */
25#include "nghttp2_queue.h"
26
27#include <string.h>
28#include <assert.h>
29
30void nghttp2_queue_init(nghttp2_queue *queue) {
31  queue->front = queue->back = NULL;
32}
33
34void nghttp2_queue_free(nghttp2_queue *queue) {
35  if (!queue) {
36    return;
37  } else {
38    nghttp2_queue_cell *p = queue->front;
39    while (p) {
40      nghttp2_queue_cell *next = p->next;
41      free(p);
42      p = next;
43    }
44  }
45}
46
47int nghttp2_queue_push(nghttp2_queue *queue, void *data) {
48  nghttp2_queue_cell *new_cell =
49      (nghttp2_queue_cell *)malloc(sizeof(nghttp2_queue_cell));
50  if (!new_cell) {
51    return NGHTTP2_ERR_NOMEM;
52  }
53  new_cell->data = data;
54  new_cell->next = NULL;
55  if (queue->back) {
56    queue->back->next = new_cell;
57    queue->back = new_cell;
58
59  } else {
60    queue->front = queue->back = new_cell;
61  }
62  return 0;
63}
64
65void nghttp2_queue_pop(nghttp2_queue *queue) {
66  nghttp2_queue_cell *front = queue->front;
67  assert(front);
68  queue->front = front->next;
69  if (front == queue->back) {
70    queue->back = NULL;
71  }
72  free(front);
73}
74
75void *nghttp2_queue_front(nghttp2_queue *queue) {
76  assert(queue->front);
77  return queue->front->data;
78}
79
80void *nghttp2_queue_back(nghttp2_queue *queue) {
81  assert(queue->back);
82  return queue->back->data;
83}
84
85int nghttp2_queue_empty(nghttp2_queue *queue) { return queue->front == NULL; }
86