Pedro Correia / mbed-dev

mbed library sources. Supersedes mbed-src.

Fork of mbed-dev by mbed official

platform/CircularBuffer.h@180:96ed750bd169, 2018-01-17 (annotated)

Committer:
Anna Bridge
Date:
Wed Jan 17 15:23:54 2018 +0000
Revision:
180:96ed750bd169
Parent:
178:79309dc6340a
Child:
184:08ed48f1de7f
mbed-dev libray. Release version 158

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 149:156823d33999 1 /* mbed Microcontroller Library
<> 149:156823d33999 2 * Copyright (c) 2015 ARM Limited
<> 149:156823d33999 3 *
<> 149:156823d33999 4 * Licensed under the Apache License, Version 2.0 (the "License");
<> 149:156823d33999 5 * you may not use this file except in compliance with the License.
<> 149:156823d33999 6 * You may obtain a copy of the License at
<> 149:156823d33999 7 *
<> 149:156823d33999 8 * http://www.apache.org/licenses/LICENSE-2.0
<> 149:156823d33999 9 *
<> 149:156823d33999 10 * Unless required by applicable law or agreed to in writing, software
<> 149:156823d33999 11 * distributed under the License is distributed on an "AS IS" BASIS,
<> 149:156823d33999 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 149:156823d33999 13 * See the License for the specific language governing permissions and
<> 149:156823d33999 14 * limitations under the License.
<> 149:156823d33999 15 */
<> 149:156823d33999 16 #ifndef MBED_CIRCULARBUFFER_H
<> 149:156823d33999 17 #define MBED_CIRCULARBUFFER_H
<> 149:156823d33999 18
<> 160:d5399cc887bb 19 #include "platform/mbed_critical.h"
<> 149:156823d33999 20
<> 149:156823d33999 21 namespace mbed {
<> 149:156823d33999 22 /** \addtogroup platform */
AnnaBridge 178:79309dc6340a 23 /** @{*/
AnnaBridge 178:79309dc6340a 24 /**
AnnaBridge 178:79309dc6340a 25 * \defgroup platform_CircularBuffer CircularBuffer functions
AnnaBridge 178:79309dc6340a 26 * @{
AnnaBridge 178:79309dc6340a 27 */
<> 149:156823d33999 28
<> 149:156823d33999 29 /** Templated Circular buffer class
<> 149:156823d33999 30 *
AnnaBridge 167:e84263d55307 31 * @note Synchronization level: Interrupt safe
<> 149:156823d33999 32 */
<> 149:156823d33999 33 template<typename T, uint32_t BufferSize, typename CounterType = uint32_t>
<> 149:156823d33999 34 class CircularBuffer {
<> 149:156823d33999 35 public:
<> 149:156823d33999 36 CircularBuffer() : _head(0), _tail(0), _full(false) {
<> 149:156823d33999 37 }
<> 149:156823d33999 38
<> 149:156823d33999 39 ~CircularBuffer() {
<> 149:156823d33999 40 }
<> 149:156823d33999 41
<> 149:156823d33999 42 /** Push the transaction to the buffer. This overwrites the buffer if it's
<> 149:156823d33999 43 * full
<> 149:156823d33999 44 *
<> 149:156823d33999 45 * @param data Data to be pushed to the buffer
<> 149:156823d33999 46 */
<> 149:156823d33999 47 void push(const T& data) {
<> 149:156823d33999 48 core_util_critical_section_enter();
<> 149:156823d33999 49 if (full()) {
<> 149:156823d33999 50 _tail++;
<> 149:156823d33999 51 _tail %= BufferSize;
<> 149:156823d33999 52 }
<> 149:156823d33999 53 _pool[_head++] = data;
<> 149:156823d33999 54 _head %= BufferSize;
<> 149:156823d33999 55 if (_head == _tail) {
<> 149:156823d33999 56 _full = true;
<> 149:156823d33999 57 }
<> 149:156823d33999 58 core_util_critical_section_exit();
<> 149:156823d33999 59 }
<> 149:156823d33999 60
<> 149:156823d33999 61 /** Pop the transaction from the buffer
<> 149:156823d33999 62 *
<> 149:156823d33999 63 * @param data Data to be pushed to the buffer
<> 149:156823d33999 64 * @return True if the buffer is not empty and data contains a transaction, false otherwise
<> 149:156823d33999 65 */
<> 149:156823d33999 66 bool pop(T& data) {
<> 149:156823d33999 67 bool data_popped = false;
<> 149:156823d33999 68 core_util_critical_section_enter();
<> 149:156823d33999 69 if (!empty()) {
<> 149:156823d33999 70 data = _pool[_tail++];
<> 149:156823d33999 71 _tail %= BufferSize;
<> 149:156823d33999 72 _full = false;
<> 149:156823d33999 73 data_popped = true;
<> 149:156823d33999 74 }
<> 149:156823d33999 75 core_util_critical_section_exit();
<> 149:156823d33999 76 return data_popped;
<> 149:156823d33999 77 }
<> 149:156823d33999 78
<> 149:156823d33999 79 /** Check if the buffer is empty
<> 149:156823d33999 80 *
<> 149:156823d33999 81 * @return True if the buffer is empty, false if not
<> 149:156823d33999 82 */
AnnaBridge 167:e84263d55307 83 bool empty() const {
<> 149:156823d33999 84 core_util_critical_section_enter();
<> 149:156823d33999 85 bool is_empty = (_head == _tail) && !_full;
<> 149:156823d33999 86 core_util_critical_section_exit();
<> 149:156823d33999 87 return is_empty;
<> 149:156823d33999 88 }
<> 149:156823d33999 89
<> 149:156823d33999 90 /** Check if the buffer is full
<> 149:156823d33999 91 *
<> 149:156823d33999 92 * @return True if the buffer is full, false if not
<> 149:156823d33999 93 */
AnnaBridge 167:e84263d55307 94 bool full() const {
<> 149:156823d33999 95 core_util_critical_section_enter();
<> 149:156823d33999 96 bool full = _full;
<> 149:156823d33999 97 core_util_critical_section_exit();
<> 149:156823d33999 98 return full;
<> 149:156823d33999 99 }
<> 149:156823d33999 100
<> 149:156823d33999 101 /** Reset the buffer
<> 149:156823d33999 102 *
<> 149:156823d33999 103 */
<> 149:156823d33999 104 void reset() {
<> 149:156823d33999 105 core_util_critical_section_enter();
<> 149:156823d33999 106 _head = 0;
<> 149:156823d33999 107 _tail = 0;
<> 149:156823d33999 108 _full = false;
<> 149:156823d33999 109 core_util_critical_section_exit();
<> 149:156823d33999 110 }
<> 149:156823d33999 111
Anna Bridge 180:96ed750bd169 112 /** Get the number of elements currently stored in the circular_buffer */
Anna Bridge 180:96ed750bd169 113 CounterType size() const {
Anna Bridge 180:96ed750bd169 114 core_util_critical_section_enter();
Anna Bridge 180:96ed750bd169 115 CounterType elements;
Anna Bridge 180:96ed750bd169 116 if (!_full) {
Anna Bridge 180:96ed750bd169 117 if (_head < _tail) {
Anna Bridge 180:96ed750bd169 118 elements = BufferSize + _head - _tail;
Anna Bridge 180:96ed750bd169 119 } else {
Anna Bridge 180:96ed750bd169 120 elements = _head - _tail;
Anna Bridge 180:96ed750bd169 121 }
Anna Bridge 180:96ed750bd169 122 } else {
Anna Bridge 180:96ed750bd169 123 elements = BufferSize;
Anna Bridge 180:96ed750bd169 124 }
Anna Bridge 180:96ed750bd169 125 core_util_critical_section_exit();
Anna Bridge 180:96ed750bd169 126 return elements;
Anna Bridge 180:96ed750bd169 127 }
Anna Bridge 180:96ed750bd169 128
<> 149:156823d33999 129 private:
<> 149:156823d33999 130 T _pool[BufferSize];
<> 149:156823d33999 131 volatile CounterType _head;
<> 149:156823d33999 132 volatile CounterType _tail;
<> 149:156823d33999 133 volatile bool _full;
<> 149:156823d33999 134 };
<> 149:156823d33999 135
AnnaBridge 178:79309dc6340a 136 /**@}*/
AnnaBridge 178:79309dc6340a 137
AnnaBridge 178:79309dc6340a 138 /**@}*/
AnnaBridge 178:79309dc6340a 139
<> 149:156823d33999 140 }
<> 149:156823d33999 141
<> 149:156823d33999 142 #endif
<> 149:156823d33999 143