Ganesh Subramaniam / USBHost

USBHost library

Dependencies:   FATFileSystem

Dependents:   Project RoboticsCatAndMouse_HumanDriver RoboticsCatAndMouse_AutonomousDriver

Fork of USBHost by mbed official

USBHostSerial/MtxCircBuffer.h@0:a554658735bf, 2013-03-06 (annotated)

Committer:
mbed_official
Date:
Wed Mar 06 16:27:14 2013 +0000
Revision:
0:a554658735bf
Child:
4:b320d68e98e7
first commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 0:a554658735bf 1 /* Copyright (c) 2010-2011 mbed.org, MIT License
mbed_official 0:a554658735bf 2 *
mbed_official 0:a554658735bf 3 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
mbed_official 0:a554658735bf 4 * and associated documentation files (the "Software"), to deal in the Software without
mbed_official 0:a554658735bf 5 * restriction, including without limitation the rights to use, copy, modify, merge, publish,
mbed_official 0:a554658735bf 6 * distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
mbed_official 0:a554658735bf 7 * Software is furnished to do so, subject to the following conditions:
mbed_official 0:a554658735bf 8 *
mbed_official 0:a554658735bf 9 * The above copyright notice and this permission notice shall be included in all copies or
mbed_official 0:a554658735bf 10 * substantial portions of the Software.
mbed_official 0:a554658735bf 11 *
mbed_official 0:a554658735bf 12 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
mbed_official 0:a554658735bf 13 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
mbed_official 0:a554658735bf 14 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
mbed_official 0:a554658735bf 15 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
mbed_official 0:a554658735bf 16 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
mbed_official 0:a554658735bf 17 */
mbed_official 0:a554658735bf 18
mbed_official 0:a554658735bf 19 #ifndef MTXCIRCBUFFER_H
mbed_official 0:a554658735bf 20 #define MTXCIRCBUFFER_H
mbed_official 0:a554658735bf 21
mbed_official 0:a554658735bf 22 #include "stdint.h"
mbed_official 0:a554658735bf 23 #include "rtos.h"
mbed_official 0:a554658735bf 24
mbed_official 0:a554658735bf 25 //Mutex protected circular buffer
mbed_official 0:a554658735bf 26 template<typename T, int size>
mbed_official 0:a554658735bf 27 class MtxCircBuffer {
mbed_official 0:a554658735bf 28 public:
mbed_official 0:a554658735bf 29
mbed_official 0:a554658735bf 30 MtxCircBuffer() {
mbed_official 0:a554658735bf 31 write = 0;
mbed_official 0:a554658735bf 32 read = 0;
mbed_official 0:a554658735bf 33 }
mbed_official 0:a554658735bf 34
mbed_official 0:a554658735bf 35 bool isFull() {
mbed_official 0:a554658735bf 36 mtx.lock();
mbed_official 0:a554658735bf 37 bool r = (((write + 1) % size) == read);
mbed_official 0:a554658735bf 38 mtx.unlock();
mbed_official 0:a554658735bf 39 return r;
mbed_official 0:a554658735bf 40 }
mbed_official 0:a554658735bf 41
mbed_official 0:a554658735bf 42 bool isEmpty() {
mbed_official 0:a554658735bf 43 mtx.lock();
mbed_official 0:a554658735bf 44 bool r = (read == write);
mbed_official 0:a554658735bf 45 mtx.unlock();
mbed_official 0:a554658735bf 46 return r;
mbed_official 0:a554658735bf 47 }
mbed_official 0:a554658735bf 48
mbed_official 0:a554658735bf 49 void queue(T k) {
mbed_official 0:a554658735bf 50 mtx.lock();
mbed_official 0:a554658735bf 51 while (((write + 1) % size) == read) {
mbed_official 0:a554658735bf 52 mtx.unlock();
mbed_official 0:a554658735bf 53 Thread::wait(10);
mbed_official 0:a554658735bf 54 mtx.lock();
mbed_official 0:a554658735bf 55 }
mbed_official 0:a554658735bf 56 buf[write++] = k;
mbed_official 0:a554658735bf 57 write %= size;
mbed_official 0:a554658735bf 58 mtx.unlock();
mbed_official 0:a554658735bf 59 }
mbed_official 0:a554658735bf 60
mbed_official 0:a554658735bf 61 uint16_t available() {
mbed_official 0:a554658735bf 62 mtx.lock();
mbed_official 0:a554658735bf 63 uint16_t a = (write >= read) ? (write - read) : (size - read + write);
mbed_official 0:a554658735bf 64 mtx.unlock();
mbed_official 0:a554658735bf 65 return a;
mbed_official 0:a554658735bf 66 }
mbed_official 0:a554658735bf 67
mbed_official 0:a554658735bf 68 bool dequeue(T * c) {
mbed_official 0:a554658735bf 69 mtx.lock();
mbed_official 0:a554658735bf 70 bool empty = (read == write);
mbed_official 0:a554658735bf 71 if (!empty) {
mbed_official 0:a554658735bf 72 *c = buf[read++];
mbed_official 0:a554658735bf 73 read %= size;
mbed_official 0:a554658735bf 74 }
mbed_official 0:a554658735bf 75 mtx.unlock();
mbed_official 0:a554658735bf 76 return (!empty);
mbed_official 0:a554658735bf 77 }
mbed_official 0:a554658735bf 78
mbed_official 0:a554658735bf 79 private:
mbed_official 0:a554658735bf 80 volatile uint16_t write;
mbed_official 0:a554658735bf 81 volatile uint16_t read;
mbed_official 0:a554658735bf 82 volatile T buf[size];
mbed_official 0:a554658735bf 83 Mutex mtx;
mbed_official 0:a554658735bf 84 };
mbed_official 0:a554658735bf 85
mbed_official 0:a554658735bf 86 #endif
mbed_official 0:a554658735bf 87
mbed_official 0:a554658735bf 88