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- /* mbed USBHost Library
- * Copyright (c) 2006-2013 ARM Limited
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
- #ifndef MTXCIRCBUFFER_H
- #define MTXCIRCBUFFER_H
-
- #include "stdint.h"
- #include "rtos.h"
-
- //Mutex protected circular buffer
- template<typename T, int size>
- class MtxCircBuffer {
- public:
-
- MtxCircBuffer() {
- write = 0;
- read = 0;
- }
-
- bool isFull() {
- mtx.lock();
- bool r = (((write + 1) % size) == read);
- mtx.unlock();
- return r;
- }
-
- bool isEmpty() {
- mtx.lock();
- bool r = (read == write);
- mtx.unlock();
- return r;
- }
-
- void flush() {
- write = 0;
- read = 0;
- }
-
- void queue(T k) {
- mtx.lock();
- while (((write + 1) % size) == read) {
- mtx.unlock();
- Thread::wait(10);
- mtx.lock();
- }
- buf[write++] = k;
- write %= size;
- mtx.unlock();
- }
-
- uint16_t available() {
- mtx.lock();
- uint16_t a = (write >= read) ? (write - read) : (size - read + write);
- mtx.unlock();
- return a;
- }
-
- bool dequeue(T * c) {
- mtx.lock();
- bool empty = (read == write);
- if (!empty) {
- *c = buf[read++];
- read %= size;
- }
- mtx.unlock();
- return (!empty);
- }
-
- private:
- volatile uint16_t write;
- volatile uint16_t read;
- volatile T buf[size];
- Mutex mtx;
- };
-
- #endif
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