Marco Mayer / Mbed OS Queue

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mbed-os/features/unsupported/USBHost/USBHostSerial/MtxCircBuffer.h@0:6bf0743ece18, 2020-03-28 (annotated)

Committer:
demayer
Date:
Sat Mar 28 15:28:19 2020 +0000
Revision:
0:6bf0743ece18
IMU Thread with an event-queue running parallel to handle tasks like a 5 times blinking LED. Button with interrupt detected.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
demayer 0:6bf0743ece18 1 /* mbed USBHost Library
demayer 0:6bf0743ece18 2 * Copyright (c) 2006-2013 ARM Limited
demayer 0:6bf0743ece18 3 *
demayer 0:6bf0743ece18 4 * Licensed under the Apache License, Version 2.0 (the "License");
demayer 0:6bf0743ece18 5 * you may not use this file except in compliance with the License.
demayer 0:6bf0743ece18 6 * You may obtain a copy of the License at
demayer 0:6bf0743ece18 7 *
demayer 0:6bf0743ece18 8 * http://www.apache.org/licenses/LICENSE-2.0
demayer 0:6bf0743ece18 9 *
demayer 0:6bf0743ece18 10 * Unless required by applicable law or agreed to in writing, software
demayer 0:6bf0743ece18 11 * distributed under the License is distributed on an "AS IS" BASIS,
demayer 0:6bf0743ece18 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
demayer 0:6bf0743ece18 13 * See the License for the specific language governing permissions and
demayer 0:6bf0743ece18 14 * limitations under the License.
demayer 0:6bf0743ece18 15 */
demayer 0:6bf0743ece18 16
demayer 0:6bf0743ece18 17 #ifndef MTXCIRCBUFFER_H
demayer 0:6bf0743ece18 18 #define MTXCIRCBUFFER_H
demayer 0:6bf0743ece18 19
demayer 0:6bf0743ece18 20 #include "stdint.h"
demayer 0:6bf0743ece18 21 #include "rtos.h"
demayer 0:6bf0743ece18 22
demayer 0:6bf0743ece18 23 //Mutex protected circular buffer
demayer 0:6bf0743ece18 24 template<typename T, int size>
demayer 0:6bf0743ece18 25 class MtxCircBuffer {
demayer 0:6bf0743ece18 26 public:
demayer 0:6bf0743ece18 27
demayer 0:6bf0743ece18 28 MtxCircBuffer() {
demayer 0:6bf0743ece18 29 write = 0;
demayer 0:6bf0743ece18 30 read = 0;
demayer 0:6bf0743ece18 31 }
demayer 0:6bf0743ece18 32
demayer 0:6bf0743ece18 33 bool isFull() {
demayer 0:6bf0743ece18 34 mtx.lock();
demayer 0:6bf0743ece18 35 bool r = (((write + 1) % size) == read);
demayer 0:6bf0743ece18 36 mtx.unlock();
demayer 0:6bf0743ece18 37 return r;
demayer 0:6bf0743ece18 38 }
demayer 0:6bf0743ece18 39
demayer 0:6bf0743ece18 40 bool isEmpty() {
demayer 0:6bf0743ece18 41 mtx.lock();
demayer 0:6bf0743ece18 42 bool r = (read == write);
demayer 0:6bf0743ece18 43 mtx.unlock();
demayer 0:6bf0743ece18 44 return r;
demayer 0:6bf0743ece18 45 }
demayer 0:6bf0743ece18 46
demayer 0:6bf0743ece18 47 void flush() {
demayer 0:6bf0743ece18 48 write = 0;
demayer 0:6bf0743ece18 49 read = 0;
demayer 0:6bf0743ece18 50 }
demayer 0:6bf0743ece18 51
demayer 0:6bf0743ece18 52 void queue(T k) {
demayer 0:6bf0743ece18 53 mtx.lock();
demayer 0:6bf0743ece18 54 while (((write + 1) % size) == read) {
demayer 0:6bf0743ece18 55 mtx.unlock();
demayer 0:6bf0743ece18 56 Thread::wait(10);
demayer 0:6bf0743ece18 57 mtx.lock();
demayer 0:6bf0743ece18 58 }
demayer 0:6bf0743ece18 59 buf[write++] = k;
demayer 0:6bf0743ece18 60 write %= size;
demayer 0:6bf0743ece18 61 mtx.unlock();
demayer 0:6bf0743ece18 62 }
demayer 0:6bf0743ece18 63
demayer 0:6bf0743ece18 64 uint16_t available() {
demayer 0:6bf0743ece18 65 mtx.lock();
demayer 0:6bf0743ece18 66 uint16_t a = (write >= read) ? (write - read) : (size - read + write);
demayer 0:6bf0743ece18 67 mtx.unlock();
demayer 0:6bf0743ece18 68 return a;
demayer 0:6bf0743ece18 69 }
demayer 0:6bf0743ece18 70
demayer 0:6bf0743ece18 71 bool dequeue(T * c) {
demayer 0:6bf0743ece18 72 mtx.lock();
demayer 0:6bf0743ece18 73 bool empty = (read == write);
demayer 0:6bf0743ece18 74 if (!empty) {
demayer 0:6bf0743ece18 75 *c = buf[read++];
demayer 0:6bf0743ece18 76 read %= size;
demayer 0:6bf0743ece18 77 }
demayer 0:6bf0743ece18 78 mtx.unlock();
demayer 0:6bf0743ece18 79 return (!empty);
demayer 0:6bf0743ece18 80 }
demayer 0:6bf0743ece18 81
demayer 0:6bf0743ece18 82 private:
demayer 0:6bf0743ece18 83 volatile uint16_t write;
demayer 0:6bf0743ece18 84 volatile uint16_t read;
demayer 0:6bf0743ece18 85 volatile T buf[size];
demayer 0:6bf0743ece18 86 Mutex mtx;
demayer 0:6bf0743ece18 87 };
demayer 0:6bf0743ece18 88
demayer 0:6bf0743ece18 89 #endif