#include <stdlib.h>
#include <string.h>
#include <stdio.h>
//------------- Person --------------
typedef struct Person {
void* derived_obj;
char* name;
void (*life)(struct Person*);
void (*live)(struct Person*);
void (*delete)(struct Person*);
} Person;
void Person_life(Person* p) {
printf("As a person, I'm %s, the life is colorfull\n", p->name);
}
void Person_live(Person* p) {
printf("As a person, I'm %s, I'd like to live in city\n", p->name);
}
void delete_Person(Person* p) {
free(p->name);
free(p);
}
Person* new_Person(const char* name) {
Person* p = (Person*)malloc(sizeof(Person));
int name_len = (int)strlen(name) + 1;
p->name = (char*)malloc(name_len);
p->life = Person_life;
p->live = Person_live;
p->derived_obj = NULL;
p->delete = delete_Person;
memcpy(p->name, name, name_len);
return p;
}
//------------- Employee --------------
typedef struct Employee {
Person* base_obj;
int id;
void (*work)(struct Person*);
} Employee;
void Employee_live(Person* p) {
printf("As an employee(id:%d), I'm %s, I'd like to live near by company\n", ((Employee*)p->derived_obj)->id, p->name);
}
void Employee_work(Person* p) {
printf("As an employee(id:%d), I'm %s, I'll try my best to work\n", ((Employee*)p->derived_obj)->id, p->name);
}
void delete_Employee(Person* p) {
Employee* e = (Employee*)p->derived_obj;
delete_Person(p);
free(e);
}
Employee* new_Employee(const char* name, int id) {
Employee* e = (Employee*)malloc(sizeof(Employee));
e->base_obj = new_Person(name);
e->base_obj->derived_obj = e;
e->base_obj->delete = delete_Employee;
e->base_obj->live = Employee_live;
e->id = id;
e->work = Employee_work;
return e;
}
#define DYNAMIC_CAST(p, TYPE) ((TYPE*)p->derived_obj)
#define STATIC_CAST(p, TYPE) ((TYPE*)p->base_obj)
int main(int argc, const char* argv[]) {
Person* p = new_Person("bacoo");
Person* e = STATIC_CAST(new_Employee("lily", 33), Person);
printf("\n------ Person ------\n");
p->life(p);
p->live(p);
printf("\n------ Employee ------\n");
e->life(e); //inherit Person::life
e->live(e); //override Person::live
DYNAMIC_CAST(e, Employee)->work(e); //new method Employee::work
p->delete(p);
e->delete(e);
return 0;
}