cam_queue.h revision 7f47f6bd7178f8bf54cf78a003a52c3f4585158c 
1/* Copyright (c) 2012, 2016, The Linux Foundation. All rights reserved.
2 *
3 * Redistribution and use in source and binary forms, with or without
4 * modification, are permitted provided that the following conditions are
5 * met:
6 *     * Redistributions of source code must retain the above copyright
7 *       notice, this list of conditions and the following disclaimer.
8 *     * Redistributions in binary form must reproduce the above
9 *       copyright notice, this list of conditions and the following
10 *       disclaimer in the documentation and/or other materials provided
11 *       with the distribution.
12 *     * Neither the name of The Linux Foundation nor the names of its
13 *       contributors may be used to endorse or promote products derived
14 *       from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
23 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
25 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
26 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 */
29
30// System dependencies
31#include <pthread.h>
32
33// Camera dependencies
34#include "cam_list.h"
35
36typedef struct {
37    struct cam_list list;
38    void *data;
39} cam_node_t;
40
41typedef struct {
42    cam_node_t head; /* dummy head */
43    uint32_t size;
44    pthread_mutex_t lock;
45} cam_queue_t;
46
47static inline int32_t cam_queue_init(cam_queue_t *queue)
48{
49    pthread_mutex_init(&queue->lock, NULL);
50    cam_list_init(&queue->head.list);
51    queue->size = 0;
52    return 0;
53}
54
55static inline int32_t cam_queue_enq(cam_queue_t *queue, void *data)
56{
57    cam_node_t *node =
58        (cam_node_t *)malloc(sizeof(cam_node_t));
59    if (NULL == node) {
60        return -1;
61    }
62
63    memset(node, 0, sizeof(cam_node_t));
64    node->data = data;
65
66    pthread_mutex_lock(&queue->lock);
67    cam_list_add_tail_node(&node->list, &queue->head.list);
68    queue->size++;
69    pthread_mutex_unlock(&queue->lock);
70
71    return 0;
72}
73
74static inline void *cam_queue_deq(cam_queue_t *queue)
75{
76    cam_node_t *node = NULL;
77    void *data = NULL;
78    struct cam_list *head = NULL;
79    struct cam_list *pos = NULL;
80
81    pthread_mutex_lock(&queue->lock);
82    head = &queue->head.list;
83    pos = head->next;
84    if (pos != head) {
85        node = member_of(pos, cam_node_t, list);
86        cam_list_del_node(&node->list);
87        queue->size--;
88    }
89    pthread_mutex_unlock(&queue->lock);
90
91    if (NULL != node) {
92        data = node->data;
93        free(node);
94    }
95
96    return data;
97}
98
99static inline int32_t cam_queue_flush(cam_queue_t *queue)
100{
101    cam_node_t *node = NULL;
102    struct cam_list *head = NULL;
103    struct cam_list *pos = NULL;
104
105    pthread_mutex_lock(&queue->lock);
106    head = &queue->head.list;
107    pos = head->next;
108
109    while(pos != head) {
110        node = member_of(pos, cam_node_t, list);
111        pos = pos->next;
112        cam_list_del_node(&node->list);
113        queue->size--;
114
115        /* TODO later to consider ptr inside data */
116        /* for now we only assume there is no ptr inside data
117         * so we free data directly */
118        if (NULL != node->data) {
119            free(node->data);
120        }
121        free(node);
122
123    }
124    queue->size = 0;
125    pthread_mutex_unlock(&queue->lock);
126    return 0;
127}
128
129static inline int32_t cam_queue_deinit(cam_queue_t *queue)
130{
131    cam_queue_flush(queue);
132    pthread_mutex_destroy(&queue->lock);
133    return 0;
134}
135