[C++] Add C++ interface for RT-Thread kernel.

components/cplusplus/Semaphore.h

@@ -0,0 +1,56 @@
+/*
+ * File      : Semaphore.h
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2016, RT-Thread Development Team
+ *
+ *  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 of the License, 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; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2016/10/1      Bernard      The first version
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include <rtthread.h>
+
+namespace rtthread {
+
+/** The Semaphore class is used to manage and protect access to a set of shared resources. */
+class Semaphore
+{
+public:
+    /** Create and Initialize a Semaphore object used for managing resources.
+      @param number of available resources; maximum index value is (count-1).
+    */
+    Semaphore(const char *name = "sem", int32_t count = 0);
+    ~Semaphore();
+
+    /** Wait until a Semaphore resource becomes available.
+      @param   millisec  timeout value or 0 in case of no time-out.
+      @return  true on success.
+    */
+    bool wait(int32_t millisec = -1);
+
+    /** Release a Semaphore resource that was obtain with Semaphore::wait.
+    */
+    void release(void);
+
+private:
+    struct rt_semaphore mID;
+};
+
+}