1 /*
2 * Copyright (c) 2019, Nordic Semiconductor ASA
3 * All rights reserved.
4 *
5 * SPDX-License-Identifier: BSD-3-Clause
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright notice, this
11 * list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
18 * contributors may be used to endorse or promote products derived from this
19 * software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
22 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY, AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
25 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 * POSSIBILITY OF SUCH DAMAGE.
32 *
33 */
34
35 /**
36 * @brief Module implementing simple FIFO queue.
37 */
38
39 #include "nrf_802154_assert.h"
40
41 #include "nrf_802154_queue.h"
42
increment_modulo(uint8_t v,uint8_t wrap_at_value)43 static inline uint8_t increment_modulo(uint8_t v, uint8_t wrap_at_value)
44 {
45 v++;
46
47 if (v >= wrap_at_value)
48 {
49 v = 0U;
50 }
51
52 return v;
53 }
54
idx2ptr(const nrf_802154_queue_t * p_queue,size_t idx)55 static inline void * idx2ptr(const nrf_802154_queue_t * p_queue, size_t idx)
56 {
57 return ((uint8_t *)(p_queue->p_memory)) + idx * p_queue->item_size;
58 }
59
nrf_802154_queue_init(nrf_802154_queue_t * p_queue,void * p_memory,size_t memory_size,size_t item_size)60 void nrf_802154_queue_init(nrf_802154_queue_t * p_queue,
61 void * p_memory,
62 size_t memory_size,
63 size_t item_size)
64 {
65 NRF_802154_ASSERT(p_queue != NULL);
66 NRF_802154_ASSERT(p_memory != NULL);
67 NRF_802154_ASSERT(item_size != 0U);
68
69 /* Due uint8_t type of nrf_802154_queue_t::item_size */
70 NRF_802154_ASSERT(item_size <= UINT8_MAX);
71
72 size_t capacity = memory_size / item_size;
73
74 /* Due simplified design, one entry in p_memory array is lost,
75 * see nrf_802154_queue_is_empty and nrf_802154_queue_is_full */
76 NRF_802154_ASSERT(capacity >= 2U);
77
78 /* Due uint8_t type of nrf_802154_queue_t::capacity */
79 NRF_802154_ASSERT(capacity <= UINT8_MAX);
80
81 p_queue->p_memory = p_memory;
82 p_queue->capacity = capacity;
83 p_queue->item_size = item_size;
84 p_queue->wridx = 0U;
85 p_queue->rdidx = 0U;
86 }
87
nrf_802154_queue_push_begin(const nrf_802154_queue_t * p_queue)88 void * nrf_802154_queue_push_begin(const nrf_802154_queue_t * p_queue)
89 {
90 return idx2ptr(p_queue, p_queue->wridx);
91 }
92
nrf_802154_queue_push_commit(nrf_802154_queue_t * p_queue)93 void nrf_802154_queue_push_commit(nrf_802154_queue_t * p_queue)
94 {
95 p_queue->wridx = increment_modulo(p_queue->wridx, p_queue->capacity);
96 }
97
nrf_802154_queue_pop_begin(const nrf_802154_queue_t * p_queue)98 void * nrf_802154_queue_pop_begin(const nrf_802154_queue_t * p_queue)
99 {
100 return idx2ptr(p_queue, p_queue->rdidx);
101 }
102
nrf_802154_queue_pop_commit(nrf_802154_queue_t * p_queue)103 void nrf_802154_queue_pop_commit(nrf_802154_queue_t * p_queue)
104 {
105 p_queue->rdidx = increment_modulo(p_queue->rdidx, p_queue->capacity);
106 }
107
nrf_802154_queue_is_full(const nrf_802154_queue_t * p_queue)108 bool nrf_802154_queue_is_full(const nrf_802154_queue_t * p_queue)
109 {
110 size_t wridx;
111
112 wridx = increment_modulo(p_queue->wridx, p_queue->capacity);
113
114 return (p_queue->rdidx == wridx);
115 }
116
