1 /*
2  * Copyright (C) 2007 - 2019 Xilinx, Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without modification,
6  * are permitted provided that the following conditions are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright notice,
9  *    this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright notice,
11  *    this list of conditions and the following disclaimer in the documentation
12  *    and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
17  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
19  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
21  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
24  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
25  * OF SUCH DAMAGE.
26  *
27  * This file is part of the lwIP TCP/IP stack.
28  *
29  */
30 
31 #include <stdlib.h>
32 
33 #include "netif/xpqueue.h"
34 #include "xil_printf.h"
35 
36 #define NUM_QUEUES    2
37 
38 pq_queue_t pq_queue[NUM_QUEUES];
39 
40 pq_queue_t *
pq_create_queue()41 pq_create_queue()
42 {
43     static int i;
44     pq_queue_t *q = NULL;
45 
46     if (i >= NUM_QUEUES) {
47         xil_printf("ERR: Max Queues allocated\n\r");
48         return q;
49     }
50 
51     q = &pq_queue[i++];
52 
53     if (!q)
54         return q;
55 
56     q->head = q->tail = q->len = 0;
57 
58     return q;
59 }
60 
61 int
pq_enqueue(pq_queue_t * q,void * p)62 pq_enqueue(pq_queue_t *q, void *p)
63 {
64     if (q->len == PQ_QUEUE_SIZE)
65         return -1;
66 
67     q->data[q->head] = p;
68     q->head = (q->head + 1)%PQ_QUEUE_SIZE;
69     q->len++;
70 
71     return 0;
72 }
73 
74 void*
pq_dequeue(pq_queue_t * q)75 pq_dequeue(pq_queue_t *q)
76 {
77     int ptail;
78 
79     if (q->len == 0)
80         return NULL;
81 
82     ptail = q->tail;
83     q->tail = (q->tail + 1)%PQ_QUEUE_SIZE;
84     q->len--;
85 
86     return q->data[ptail];
87 }
88 
89 int
pq_qlength(pq_queue_t * q)90 pq_qlength(pq_queue_t *q)
91 {
92     return q->len;
93 }
94