1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
|
// SPDX-FileCopyrightText: 2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
//
// SPDX-License-Identifier: MIT
/*
* This example shows how to dequeue nodes from a wfcqueue.
*/
#include <stdio.h>
#include <stdlib.h>
#include <urcu/wfcqueue.h> /* Wait-free concurrent queue */
#include <urcu/compiler.h> /* For CAA_ARRAY_SIZE */
/*
* Nodes populated into the queue.
*/
struct mynode {
int value; /* Node content */
struct cds_wfcq_node node; /* Chaining in queue */
};
int main(void)
{
int values[] = { -5, 42, 36, 24, };
struct cds_wfcq_head myqueue_head; /* Queue head */
struct cds_wfcq_tail myqueue_tail; /* Queue tail */
unsigned int i;
int ret = 0;
cds_wfcq_init(&myqueue_head, &myqueue_tail);
/*
* Enqueue nodes.
*/
for (i = 0; i < CAA_ARRAY_SIZE(values); i++) {
struct mynode *node;
node = malloc(sizeof(*node));
if (!node) {
ret = -1;
goto end;
}
cds_wfcq_node_init(&node->node);
node->value = values[i];
cds_wfcq_enqueue(&myqueue_head, &myqueue_tail,
&node->node);
}
/*
* Dequeue each node from the queue. Those will be dequeued from
* the oldest (first enqueued) to the newest (last enqueued).
*/
printf("dequeued content:");
for (;;) {
struct cds_wfcq_node *qnode;
struct mynode *node;
qnode = cds_wfcq_dequeue_blocking(&myqueue_head, &myqueue_tail);
if (!qnode) {
break; /* Queue is empty. */
}
/* Getting the container structure from the node */
node = caa_container_of(qnode, struct mynode, node);
printf(" %d", node->value);
free(node);
}
printf("\n");
end:
cds_wfcq_destroy(&myqueue_head, &myqueue_tail);
return ret;
}
|
