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?
User | Revision | Line number | New contents of line |
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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 |