Implemented C++11 stype wrapper and example.

extras/cpp11/include/mutex.hpp

@@ -0,0 +1,96 @@
+/* --------------------------------------------------------------------------*\
+ * 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_
+