OOP-in-C

My rules for OOP in C

typedef struct Base Base;
typedef struct Subclass Subclass;
typedef void AbstractBase;
typedef void AbstractSubclass;

struct Base{
  const char *name;
};

struct SubClass{
  Base Base;           //first field is the Object it extends (its super class) it has the same name as the type.
  double extraField;
};


AbstractBase *Base_create(unsigned int size){
   return malloc(size==0?sizeof(Base):size);
}

AbstractBase *Subclass_create(unsigned int size){
   return Base_create(size==0?sizeof(Subclass):size);
}

const char *  Base_getName(Base *base){
   return base->name;
}

bool Subclass_nameIsJohn (Subclass *subclass){
   //call function with "Subclass" as "Base"
   const char *myName = Base_getName(&subclass->Base);
   
   return strcmp(myName,"John")==0;
}

// Base *myBase = (Base *)mySubclassObject
// is the same as
// Base *myBase = &mySubclassObject->Base;