CircBuffer.h

00001 /* Copyright (c) 2010-2011 mbed.org, MIT License
00002 *
00003 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
00004 * and associated documentation files (the "Software"), to deal in the Software without
00005 * restriction, including without limitation the rights to use, copy, modify, merge, publish,
00006 * distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
00007 * Software is furnished to do so, subject to the following conditions:
00008 *
00009 * The above copyright notice and this permission notice shall be included in all copies or
00010 * substantial portions of the Software.
00011 *
00012 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
00013 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00014 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
00015 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00016 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00017 */
00018 
00019 #ifndef CIRCBUFFER_H
00020 #define CIRCBUFFER_H
00021 #include "pinscape.h"
00022 
00023 template <class T>
00024 class CircBuffer {
00025 public:
00026     CircBuffer(int length) {
00027         write = 0;
00028         read = 0;
00029         size = length + 1;
00030         buf = new T[size];
00031     };
00032 
00033     ~CircBuffer() {
00034         delete [] buf;
00035      }
00036 
00037     bool isFull() {
00038         return ((write + 1) % size == read);
00039     };
00040 
00041     bool isEmpty() {
00042         return (read == write);
00043     };
00044 
00045     void queue(T k) {
00046         if (isFull()) {
00047             read++;
00048             read %= size;
00049         }
00050         buf[write++] = k;
00051         write %= size;
00052     }
00053 
00054     uint16_t available() {
00055         return (write >= read) ? write - read : size - read + write;
00056     };
00057 
00058     bool dequeue(T * c) {
00059         bool empty = isEmpty();
00060         if (!empty) {
00061             *c = buf[read++];
00062             read %= size;
00063         }
00064         return(!empty);
00065     };
00066 
00067 private:
00068     volatile uint16_t write;
00069     volatile uint16_t read;
00070     uint16_t size;
00071     T * buf;
00072 };
00073 
00074 #endif