portapack-mayhem/firmware/common/message_queue.hpp
Jared Boone 035ec84f04 Wrap MessageQueue.push() with mutex.
This addresses issue #61, occasional FIFO/data corruption. With the mutex, any thread on one core can write to the FIFO. But still, only one thread on one core should read from the FIFO.
2015-08-26 14:18:03 -07:00

93 lines
2.0 KiB
C++

/*
* Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
*
* This file is part of PortaPack.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifndef __MESSAGE_QUEUE_H__
#define __MESSAGE_QUEUE_H__
#include <cstdint>
#include "message.hpp"
#include "fifo.hpp"
#include "lpc43xx_cpp.hpp"
using namespace lpc43xx;
#include <ch.h>
template<size_t K>
class MessageQueue {
public:
MessageQueue() {
chMtxInit(&mutex_write);
}
template<typename T>
bool push(const T& message) {
static_assert(sizeof(T) <= Message::MAX_SIZE, "Message::MAX_SIZE too small for message type");
static_assert(std::is_base_of<Message, T>::value, "type is not based on Message");
return push(&message, sizeof(message));
}
size_t pop(void* const buf, const size_t len) {
return fifo.out_r(buf, len);
}
size_t len() const {
return fifo.len();
}
bool is_empty() const {
return fifo.is_empty();
}
private:
FIFO<uint8_t, K> fifo;
Mutex mutex_write;
bool push(const void* const buf, const size_t len) {
chMtxLock(&mutex_write);
const auto result = fifo.in_r(buf, len);
chMtxUnlock();
const bool success = (result == len);
if( success ) {
signal();
}
return success;
}
#if defined(LPC43XX_M0)
void signal() {
creg::m0apptxevent::assert();
}
#endif
#if defined(LPC43XX_M4)
void signal() {
creg::m4txevent::assert();
}
#endif
};
#endif/*__MESSAGE_QUEUE_H__*/