Reintroduce C++ support and add usage tests for C++ (#4)

Reviewed-on: #4
Co-authored-by: Abdelrahman <said.abdelrahman89@gmail.com>
Co-committed-by: Abdelrahman <said.abdelrahman89@gmail.com>

src/common/assert/assert.h

@@ -1,10 +1,18 @@
 // vim:fileencoding=utf-8:foldmethod=marker
 
+#ifndef WAPP_ASSERT_H
+#define WAPP_ASSERT_H
+
 #include "../aliases/aliases.h"
+#include "../platform/platform.h"
 #include <stdio.h>
 #include <stdlib.h>
 #include <inttypes.h>
 
+#ifdef WAPP_PLATFORM_CPP
+BEGIN_C_LINKAGE
+#endif // !WAPP_PLATFORM_CPP
+
 #define wapp_static_assert(EXPR, MSG) extern char ASSERTION_FAILED[EXPR ? 1 : -1]
 #define wapp_runtime_assert(EXPR, MSG) __wapp_runtime_assert(EXPR, MSG)
 
@@ -25,3 +33,9 @@
     abort();                                                                          \
   }                                                                                   \
 } while(false)
+
+#ifdef WAPP_PLATFORM_CPP
+END_C_LINKAGE
+#endif // !WAPP_PLATFORM_CPP
+
+#endif // !WAPP_ASSERT_H