#ifndef OBJECT_H #define OBJECT_H typedef void (*Execute)(struct Object *a_This); typedef struct Object* (*Allocate)(); typedef struct _Object_Vtable {  char *name;  Execute exe; }Object_Vtable; typedef struct _baseCmd {  Object_Vtable vtable; }BaseCmd; // --- for common --- // BaseCmd* new(Allocate newObj); void delete(void * item); // --------------------------// // --- for BaseCmd --- // BaseCmd* NewBaseCmd(); void Exe_BaseCmd(BaseCmd *a_This); // --------------------------// // --- for HomeCmd --- // typedef struct _homeCmd {  Object_Vtable vtable; }HomeCmd; BaseCmd* NewHomeCmd(); void Exe_HomeCmd(HomeCmd *a_This); // --------------------------// #endif

#include "Cloud.h" // --- for common --- // BaseCmd* new(Allocate newObj) {  BaseCmd * obj = newObj();  return obj; } void delete(void * item) {  free(item); } // --------------------------// // --- for BaseCmd --- // BaseCmd* NewBaseCmd() {  BaseCmd * cmd = malloc(sizeof(BaseCmd));  cmd->vtable.name = "Cloud";  cmd->vtable.exe = Exe_BaseCmd;  return cmd; } void Exe_BaseCmd(BaseCmd *a_This) {  printf("do base command = %s/n",a_This->vtable.name); } // --------------------------// // --- for HomeCmd --- // BaseCmd* NewHomeCmd() {  HomeCmd * cmd = malloc(sizeof(HomeCmd));  cmd->vtable.name = "Home";  cmd->vtable.exe = Exe_HomeCmd;  return cmd; } void Exe_HomeCmd(HomeCmd *a_This) {  printf("do home command = %s/n",a_This->vtable.name); } // --------------------------//

#include <stdio.h> #include <stdlib.h> #include "Cloud.h" int main (int argc, const char * argv[]) {  BaseCmd* cmd = new(NewBaseCmd);  cmd->vtable.exe(cmd);  delete(cmd);  BaseCmd* cmd2 = new(NewHomeCmd);  cmd2->vtable.exe(cmd2);  delete(cmd2);     return 0; }