Merge pull request #19 from hhuOS/pr/c++-compat

doomgeneric.h: Make interface compatible with C++

Author: ozkl

doomgeneric/doomgeneric.h

@@ -26,6 +26,10 @@ typedef uint32_t pixel_t;
 
 extern pixel_t* DG_ScreenBuffer;
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 void doomgeneric_Create(int argc, char **argv);
 void doomgeneric_Tick();
 
@@ -38,4 +42,8 @@ uint32_t DG_GetTicksMs();
 int DG_GetKey(int* pressed, unsigned char* key);
 void DG_SetWindowTitle(const char * title);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif //DOOM_GENERIC