esp-open-rtos/extras/cpp11/include/mutex.hpp
2017-09-28 17:55:54 +02:00

96 lines
3.2 KiB
C++

/* --------------------------------------------------------------------------*\
* Copyright 2017 Florian Eich <florian.eich@gmail.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE./ limitations under the License.
\* --------------------------------------------------------------------------*/
#ifndef ESP_OPEN_RTOS_EXTRAS_CPP11_MUTEX_HPP_
#define ESP_OPEN_RTOS_EXTRAS_CPP11_MUTEX_HPP_
#include "FreeRTOS.h"
#include "semphr.h"
namespace cxx {
/*!
* \brief Wrapper for FreeRTOS SemaphoreHande_t.
*/
class mutex
{
public:
/*!
* \brief Default constructor for mutex class.
*/
mutex() : _mutex(xSemaphoreCreateMutex()) {}
// Disable copy construction and assigment.
mutex(const mutex &) = delete;
mutex & operator=(const mutex &) = delete;
/*!
* \brief Destructor for mutex class releases underlying resource actively.
*/
~mutex() { vQueueDelete(_mutex); }
/*!
* \brief Check if mutex is usable.
* \returns boolean: true if usable.
*/
bool usable() const { return _mutex != nullptr; }
/*!
* \brief Try locking mutex with no timeout.
* \returns boolean: true if successfully locked.
*/
bool try_lock() { return xSemaphoreTake(_mutex, portMAX_DELAY) == pdTRUE; }
/*!
* \brief Try locking mutex with timeout.
* \param ms Timeout delay in milliseconds.
* \returns boolean: true if successfully locked.
*/
bool try_lock(const unsigned long ms) {
return xSemaphoreTake(_mutex, ms / portTICK_PERIOD_MS) == pdTRUE;
}
/*!
* \brief Unlock mutex.
* \returns boolean: true if successfully unlocked.
*/
bool unlock() { return xSemaphoreGive(_mutex) == pdTRUE; }
private:
SemaphoreHandle_t _mutex;
};
} // namespace cxx
#endif // ESP_OPEN_RTOS_EXTRAS_CPP11_MUTEX_HPP_