Marco Zecchini / Mbed OS Example_RTOS

Rtos API example

mbed-os/platform/CircularBuffer.h@0:9fca2b23d0ba, 2019-02-23 (annotated)

Committer:
marcozecchini
Date:
Sat Feb 23 12:13:36 2019 +0000
Revision:
0:9fca2b23d0ba
final commit

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marcozecchini 0:9fca2b23d0ba 1 /* mbed Microcontroller Library
marcozecchini 0:9fca2b23d0ba 2 * Copyright (c) 2015 ARM Limited
marcozecchini 0:9fca2b23d0ba 3 *
marcozecchini 0:9fca2b23d0ba 4 * Licensed under the Apache License, Version 2.0 (the "License");
marcozecchini 0:9fca2b23d0ba 5 * you may not use this file except in compliance with the License.
marcozecchini 0:9fca2b23d0ba 6 * You may obtain a copy of the License at
marcozecchini 0:9fca2b23d0ba 7 *
marcozecchini 0:9fca2b23d0ba 8 * http://www.apache.org/licenses/LICENSE-2.0
marcozecchini 0:9fca2b23d0ba 9 *
marcozecchini 0:9fca2b23d0ba 10 * Unless required by applicable law or agreed to in writing, software
marcozecchini 0:9fca2b23d0ba 11 * distributed under the License is distributed on an "AS IS" BASIS,
marcozecchini 0:9fca2b23d0ba 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
marcozecchini 0:9fca2b23d0ba 13 * See the License for the specific language governing permissions and
marcozecchini 0:9fca2b23d0ba 14 * limitations under the License.
marcozecchini 0:9fca2b23d0ba 15 */
marcozecchini 0:9fca2b23d0ba 16 #ifndef MBED_CIRCULARBUFFER_H
marcozecchini 0:9fca2b23d0ba 17 #define MBED_CIRCULARBUFFER_H
marcozecchini 0:9fca2b23d0ba 18
marcozecchini 0:9fca2b23d0ba 19 #include "platform/mbed_critical.h"
marcozecchini 0:9fca2b23d0ba 20
marcozecchini 0:9fca2b23d0ba 21 namespace mbed {
marcozecchini 0:9fca2b23d0ba 22 /** \addtogroup platform */
marcozecchini 0:9fca2b23d0ba 23 /** @{*/
marcozecchini 0:9fca2b23d0ba 24 /**
marcozecchini 0:9fca2b23d0ba 25 * \defgroup platform_CircularBuffer CircularBuffer functions
marcozecchini 0:9fca2b23d0ba 26 * @{
marcozecchini 0:9fca2b23d0ba 27 */
marcozecchini 0:9fca2b23d0ba 28
marcozecchini 0:9fca2b23d0ba 29 /** Templated Circular buffer class
marcozecchini 0:9fca2b23d0ba 30 *
marcozecchini 0:9fca2b23d0ba 31 * @note Synchronization level: Interrupt safe
marcozecchini 0:9fca2b23d0ba 32 */
marcozecchini 0:9fca2b23d0ba 33 template<typename T, uint32_t BufferSize, typename CounterType = uint32_t>
marcozecchini 0:9fca2b23d0ba 34 class CircularBuffer {
marcozecchini 0:9fca2b23d0ba 35 public:
marcozecchini 0:9fca2b23d0ba 36 CircularBuffer() : _head(0), _tail(0), _full(false) {
marcozecchini 0:9fca2b23d0ba 37 }
marcozecchini 0:9fca2b23d0ba 38
marcozecchini 0:9fca2b23d0ba 39 ~CircularBuffer() {
marcozecchini 0:9fca2b23d0ba 40 }
marcozecchini 0:9fca2b23d0ba 41
marcozecchini 0:9fca2b23d0ba 42 /** Push the transaction to the buffer. This overwrites the buffer if it's
marcozecchini 0:9fca2b23d0ba 43 * full
marcozecchini 0:9fca2b23d0ba 44 *
marcozecchini 0:9fca2b23d0ba 45 * @param data Data to be pushed to the buffer
marcozecchini 0:9fca2b23d0ba 46 */
marcozecchini 0:9fca2b23d0ba 47 void push(const T& data) {
marcozecchini 0:9fca2b23d0ba 48 core_util_critical_section_enter();
marcozecchini 0:9fca2b23d0ba 49 if (full()) {
marcozecchini 0:9fca2b23d0ba 50 _tail++;
marcozecchini 0:9fca2b23d0ba 51 _tail %= BufferSize;
marcozecchini 0:9fca2b23d0ba 52 }
marcozecchini 0:9fca2b23d0ba 53 _pool[_head++] = data;
marcozecchini 0:9fca2b23d0ba 54 _head %= BufferSize;
marcozecchini 0:9fca2b23d0ba 55 if (_head == _tail) {
marcozecchini 0:9fca2b23d0ba 56 _full = true;
marcozecchini 0:9fca2b23d0ba 57 }
marcozecchini 0:9fca2b23d0ba 58 core_util_critical_section_exit();
marcozecchini 0:9fca2b23d0ba 59 }
marcozecchini 0:9fca2b23d0ba 60
marcozecchini 0:9fca2b23d0ba 61 /** Pop the transaction from the buffer
marcozecchini 0:9fca2b23d0ba 62 *
marcozecchini 0:9fca2b23d0ba 63 * @param data Data to be pushed to the buffer
marcozecchini 0:9fca2b23d0ba 64 * @return True if the buffer is not empty and data contains a transaction, false otherwise
marcozecchini 0:9fca2b23d0ba 65 */
marcozecchini 0:9fca2b23d0ba 66 bool pop(T& data) {
marcozecchini 0:9fca2b23d0ba 67 bool data_popped = false;
marcozecchini 0:9fca2b23d0ba 68 core_util_critical_section_enter();
marcozecchini 0:9fca2b23d0ba 69 if (!empty()) {
marcozecchini 0:9fca2b23d0ba 70 data = _pool[_tail++];
marcozecchini 0:9fca2b23d0ba 71 _tail %= BufferSize;
marcozecchini 0:9fca2b23d0ba 72 _full = false;
marcozecchini 0:9fca2b23d0ba 73 data_popped = true;
marcozecchini 0:9fca2b23d0ba 74 }
marcozecchini 0:9fca2b23d0ba 75 core_util_critical_section_exit();
marcozecchini 0:9fca2b23d0ba 76 return data_popped;
marcozecchini 0:9fca2b23d0ba 77 }
marcozecchini 0:9fca2b23d0ba 78
marcozecchini 0:9fca2b23d0ba 79 /** Check if the buffer is empty
marcozecchini 0:9fca2b23d0ba 80 *
marcozecchini 0:9fca2b23d0ba 81 * @return True if the buffer is empty, false if not
marcozecchini 0:9fca2b23d0ba 82 */
marcozecchini 0:9fca2b23d0ba 83 bool empty() const {
marcozecchini 0:9fca2b23d0ba 84 core_util_critical_section_enter();
marcozecchini 0:9fca2b23d0ba 85 bool is_empty = (_head == _tail) && !_full;
marcozecchini 0:9fca2b23d0ba 86 core_util_critical_section_exit();
marcozecchini 0:9fca2b23d0ba 87 return is_empty;
marcozecchini 0:9fca2b23d0ba 88 }
marcozecchini 0:9fca2b23d0ba 89
marcozecchini 0:9fca2b23d0ba 90 /** Check if the buffer is full
marcozecchini 0:9fca2b23d0ba 91 *
marcozecchini 0:9fca2b23d0ba 92 * @return True if the buffer is full, false if not
marcozecchini 0:9fca2b23d0ba 93 */
marcozecchini 0:9fca2b23d0ba 94 bool full() const {
marcozecchini 0:9fca2b23d0ba 95 core_util_critical_section_enter();
marcozecchini 0:9fca2b23d0ba 96 bool full = _full;
marcozecchini 0:9fca2b23d0ba 97 core_util_critical_section_exit();
marcozecchini 0:9fca2b23d0ba 98 return full;
marcozecchini 0:9fca2b23d0ba 99 }
marcozecchini 0:9fca2b23d0ba 100
marcozecchini 0:9fca2b23d0ba 101 /** Reset the buffer
marcozecchini 0:9fca2b23d0ba 102 *
marcozecchini 0:9fca2b23d0ba 103 */
marcozecchini 0:9fca2b23d0ba 104 void reset() {
marcozecchini 0:9fca2b23d0ba 105 core_util_critical_section_enter();
marcozecchini 0:9fca2b23d0ba 106 _head = 0;
marcozecchini 0:9fca2b23d0ba 107 _tail = 0;
marcozecchini 0:9fca2b23d0ba 108 _full = false;
marcozecchini 0:9fca2b23d0ba 109 core_util_critical_section_exit();
marcozecchini 0:9fca2b23d0ba 110 }
marcozecchini 0:9fca2b23d0ba 111
marcozecchini 0:9fca2b23d0ba 112 /** Get the number of elements currently stored in the circular_buffer */
marcozecchini 0:9fca2b23d0ba 113 CounterType size() const {
marcozecchini 0:9fca2b23d0ba 114 core_util_critical_section_enter();
marcozecchini 0:9fca2b23d0ba 115 CounterType elements;
marcozecchini 0:9fca2b23d0ba 116 if (!_full) {
marcozecchini 0:9fca2b23d0ba 117 if (_head < _tail) {
marcozecchini 0:9fca2b23d0ba 118 elements = BufferSize + _head - _tail;
marcozecchini 0:9fca2b23d0ba 119 } else {
marcozecchini 0:9fca2b23d0ba 120 elements = _head - _tail;
marcozecchini 0:9fca2b23d0ba 121 }
marcozecchini 0:9fca2b23d0ba 122 } else {
marcozecchini 0:9fca2b23d0ba 123 elements = BufferSize;
marcozecchini 0:9fca2b23d0ba 124 }
marcozecchini 0:9fca2b23d0ba 125 core_util_critical_section_exit();
marcozecchini 0:9fca2b23d0ba 126 return elements;
marcozecchini 0:9fca2b23d0ba 127 }
marcozecchini 0:9fca2b23d0ba 128
marcozecchini 0:9fca2b23d0ba 129 private:
marcozecchini 0:9fca2b23d0ba 130 T _pool[BufferSize];
marcozecchini 0:9fca2b23d0ba 131 volatile CounterType _head;
marcozecchini 0:9fca2b23d0ba 132 volatile CounterType _tail;
marcozecchini 0:9fca2b23d0ba 133 volatile bool _full;
marcozecchini 0:9fca2b23d0ba 134 };
marcozecchini 0:9fca2b23d0ba 135
marcozecchini 0:9fca2b23d0ba 136 /**@}*/
marcozecchini 0:9fca2b23d0ba 137
marcozecchini 0:9fca2b23d0ba 138 /**@}*/
marcozecchini 0:9fca2b23d0ba 139
marcozecchini 0:9fca2b23d0ba 140 }
marcozecchini 0:9fca2b23d0ba 141
marcozecchini 0:9fca2b23d0ba 142 #endif
marcozecchini 0:9fca2b23d0ba 143