EL4121 Embedded System / mbed-os

mbed-os

Dependents:   cobaLCDJoyMotor_Thread odometry_omni_3roda_v3 odometry_omni_3roda_v1 odometry_omni_3roda_v2 ... more

platform/CircularBuffer.h@0:b74591d5ab33, 2017-12-11 (annotated)

Committer:
be_bryan
Date:
Mon Dec 11 17:54:04 2017 +0000
Revision:
0:b74591d5ab33
motor ++

Who changed what in which revision?

UserRevisionLine numberNew contents of line
be_bryan 0:b74591d5ab33 1 /* mbed Microcontroller Library
be_bryan 0:b74591d5ab33 2 * Copyright (c) 2015 ARM Limited
be_bryan 0:b74591d5ab33 3 *
be_bryan 0:b74591d5ab33 4 * Licensed under the Apache License, Version 2.0 (the "License");
be_bryan 0:b74591d5ab33 5 * you may not use this file except in compliance with the License.
be_bryan 0:b74591d5ab33 6 * You may obtain a copy of the License at
be_bryan 0:b74591d5ab33 7 *
be_bryan 0:b74591d5ab33 8 * http://www.apache.org/licenses/LICENSE-2.0
be_bryan 0:b74591d5ab33 9 *
be_bryan 0:b74591d5ab33 10 * Unless required by applicable law or agreed to in writing, software
be_bryan 0:b74591d5ab33 11 * distributed under the License is distributed on an "AS IS" BASIS,
be_bryan 0:b74591d5ab33 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
be_bryan 0:b74591d5ab33 13 * See the License for the specific language governing permissions and
be_bryan 0:b74591d5ab33 14 * limitations under the License.
be_bryan 0:b74591d5ab33 15 */
be_bryan 0:b74591d5ab33 16 #ifndef MBED_CIRCULARBUFFER_H
be_bryan 0:b74591d5ab33 17 #define MBED_CIRCULARBUFFER_H
be_bryan 0:b74591d5ab33 18
be_bryan 0:b74591d5ab33 19 #include "platform/mbed_critical.h"
be_bryan 0:b74591d5ab33 20
be_bryan 0:b74591d5ab33 21 namespace mbed {
be_bryan 0:b74591d5ab33 22 /** \addtogroup platform */
be_bryan 0:b74591d5ab33 23 /** @{*/
be_bryan 0:b74591d5ab33 24 /**
be_bryan 0:b74591d5ab33 25 * \defgroup platform_CircularBuffer CircularBuffer functions
be_bryan 0:b74591d5ab33 26 * @{
be_bryan 0:b74591d5ab33 27 */
be_bryan 0:b74591d5ab33 28
be_bryan 0:b74591d5ab33 29 /** Templated Circular buffer class
be_bryan 0:b74591d5ab33 30 *
be_bryan 0:b74591d5ab33 31 * @note Synchronization level: Interrupt safe
be_bryan 0:b74591d5ab33 32 */
be_bryan 0:b74591d5ab33 33 template<typename T, uint32_t BufferSize, typename CounterType = uint32_t>
be_bryan 0:b74591d5ab33 34 class CircularBuffer {
be_bryan 0:b74591d5ab33 35 public:
be_bryan 0:b74591d5ab33 36 CircularBuffer() : _head(0), _tail(0), _full(false) {
be_bryan 0:b74591d5ab33 37 }
be_bryan 0:b74591d5ab33 38
be_bryan 0:b74591d5ab33 39 ~CircularBuffer() {
be_bryan 0:b74591d5ab33 40 }
be_bryan 0:b74591d5ab33 41
be_bryan 0:b74591d5ab33 42 /** Push the transaction to the buffer. This overwrites the buffer if it's
be_bryan 0:b74591d5ab33 43 * full
be_bryan 0:b74591d5ab33 44 *
be_bryan 0:b74591d5ab33 45 * @param data Data to be pushed to the buffer
be_bryan 0:b74591d5ab33 46 */
be_bryan 0:b74591d5ab33 47 void push(const T& data) {
be_bryan 0:b74591d5ab33 48 core_util_critical_section_enter();
be_bryan 0:b74591d5ab33 49 if (full()) {
be_bryan 0:b74591d5ab33 50 _tail++;
be_bryan 0:b74591d5ab33 51 _tail %= BufferSize;
be_bryan 0:b74591d5ab33 52 }
be_bryan 0:b74591d5ab33 53 _pool[_head++] = data;
be_bryan 0:b74591d5ab33 54 _head %= BufferSize;
be_bryan 0:b74591d5ab33 55 if (_head == _tail) {
be_bryan 0:b74591d5ab33 56 _full = true;
be_bryan 0:b74591d5ab33 57 }
be_bryan 0:b74591d5ab33 58 core_util_critical_section_exit();
be_bryan 0:b74591d5ab33 59 }
be_bryan 0:b74591d5ab33 60
be_bryan 0:b74591d5ab33 61 /** Pop the transaction from the buffer
be_bryan 0:b74591d5ab33 62 *
be_bryan 0:b74591d5ab33 63 * @param data Data to be pushed to the buffer
be_bryan 0:b74591d5ab33 64 * @return True if the buffer is not empty and data contains a transaction, false otherwise
be_bryan 0:b74591d5ab33 65 */
be_bryan 0:b74591d5ab33 66 bool pop(T& data) {
be_bryan 0:b74591d5ab33 67 bool data_popped = false;
be_bryan 0:b74591d5ab33 68 core_util_critical_section_enter();
be_bryan 0:b74591d5ab33 69 if (!empty()) {
be_bryan 0:b74591d5ab33 70 data = _pool[_tail++];
be_bryan 0:b74591d5ab33 71 _tail %= BufferSize;
be_bryan 0:b74591d5ab33 72 _full = false;
be_bryan 0:b74591d5ab33 73 data_popped = true;
be_bryan 0:b74591d5ab33 74 }
be_bryan 0:b74591d5ab33 75 core_util_critical_section_exit();
be_bryan 0:b74591d5ab33 76 return data_popped;
be_bryan 0:b74591d5ab33 77 }
be_bryan 0:b74591d5ab33 78
be_bryan 0:b74591d5ab33 79 /** Check if the buffer is empty
be_bryan 0:b74591d5ab33 80 *
be_bryan 0:b74591d5ab33 81 * @return True if the buffer is empty, false if not
be_bryan 0:b74591d5ab33 82 */
be_bryan 0:b74591d5ab33 83 bool empty() const {
be_bryan 0:b74591d5ab33 84 core_util_critical_section_enter();
be_bryan 0:b74591d5ab33 85 bool is_empty = (_head == _tail) && !_full;
be_bryan 0:b74591d5ab33 86 core_util_critical_section_exit();
be_bryan 0:b74591d5ab33 87 return is_empty;
be_bryan 0:b74591d5ab33 88 }
be_bryan 0:b74591d5ab33 89
be_bryan 0:b74591d5ab33 90 /** Check if the buffer is full
be_bryan 0:b74591d5ab33 91 *
be_bryan 0:b74591d5ab33 92 * @return True if the buffer is full, false if not
be_bryan 0:b74591d5ab33 93 */
be_bryan 0:b74591d5ab33 94 bool full() const {
be_bryan 0:b74591d5ab33 95 core_util_critical_section_enter();
be_bryan 0:b74591d5ab33 96 bool full = _full;
be_bryan 0:b74591d5ab33 97 core_util_critical_section_exit();
be_bryan 0:b74591d5ab33 98 return full;
be_bryan 0:b74591d5ab33 99 }
be_bryan 0:b74591d5ab33 100
be_bryan 0:b74591d5ab33 101 /** Reset the buffer
be_bryan 0:b74591d5ab33 102 *
be_bryan 0:b74591d5ab33 103 */
be_bryan 0:b74591d5ab33 104 void reset() {
be_bryan 0:b74591d5ab33 105 core_util_critical_section_enter();
be_bryan 0:b74591d5ab33 106 _head = 0;
be_bryan 0:b74591d5ab33 107 _tail = 0;
be_bryan 0:b74591d5ab33 108 _full = false;
be_bryan 0:b74591d5ab33 109 core_util_critical_section_exit();
be_bryan 0:b74591d5ab33 110 }
be_bryan 0:b74591d5ab33 111
be_bryan 0:b74591d5ab33 112 /** Get the number of elements currently stored in the circular_buffer */
be_bryan 0:b74591d5ab33 113 CounterType size() const {
be_bryan 0:b74591d5ab33 114 core_util_critical_section_enter();
be_bryan 0:b74591d5ab33 115 CounterType elements;
be_bryan 0:b74591d5ab33 116 if (!_full) {
be_bryan 0:b74591d5ab33 117 if (_head < _tail) {
be_bryan 0:b74591d5ab33 118 elements = BufferSize + _head - _tail;
be_bryan 0:b74591d5ab33 119 } else {
be_bryan 0:b74591d5ab33 120 elements = _head - _tail;
be_bryan 0:b74591d5ab33 121 }
be_bryan 0:b74591d5ab33 122 } else {
be_bryan 0:b74591d5ab33 123 elements = BufferSize;
be_bryan 0:b74591d5ab33 124 }
be_bryan 0:b74591d5ab33 125 core_util_critical_section_exit();
be_bryan 0:b74591d5ab33 126 return elements;
be_bryan 0:b74591d5ab33 127 }
be_bryan 0:b74591d5ab33 128
be_bryan 0:b74591d5ab33 129 private:
be_bryan 0:b74591d5ab33 130 T _pool[BufferSize];
be_bryan 0:b74591d5ab33 131 volatile CounterType _head;
be_bryan 0:b74591d5ab33 132 volatile CounterType _tail;
be_bryan 0:b74591d5ab33 133 volatile bool _full;
be_bryan 0:b74591d5ab33 134 };
be_bryan 0:b74591d5ab33 135
be_bryan 0:b74591d5ab33 136 /**@}*/
be_bryan 0:b74591d5ab33 137
be_bryan 0:b74591d5ab33 138 /**@}*/
be_bryan 0:b74591d5ab33 139
be_bryan 0:b74591d5ab33 140 }
be_bryan 0:b74591d5ab33 141
be_bryan 0:b74591d5ab33 142 #endif
be_bryan 0:b74591d5ab33 143