SGI 標(biāo)準(zhǔn)的空間配置器 std::allocator
// Inclusion of this file is DEPRECATED. This is the original HP
// default allocator. It is provided only for backward compatibility.
//
// DO NOT USE THIS FILE unless you have an old container implementation
// that requires an allocator with the HP-style interface. SGI STL
// uses a different allocator interface. SGI-style allocators are not
// parametrized with respect to the object type; they traffic in void *
// pointers. This file is not included by any other SGI STL header.
template <class T>
inline T* allocate(ptrdiff_t size, T*) {
set_new_handler(0);
T* tmp = (T*)(::operator new((size_t)(size * sizeof(T))));
if (tmp == 0) {
cerr << "out of memory" << endl;
exit(1);
}
return tmp;
}
template <class T>
inline void deallocate(T* buffer) {
::operator delete(buffer);
}
template <class T>
class allocator {
public:
typedef T value_type;
typedef T* pointer;
typedef const T* const_pointer;
typedef T& reference;
typedef const T& const_reference;
typedef size_t size_type;
typedef ptrdiff_t difference_type;
pointer allocate(size_type n) {
return ::allocate((difference_type)n, (pointer)0);
}
void deallocate(pointer p) { ::deallocate(p); }
pointer address(reference x) { return (pointer)&x; }
const_pointer const_address(const_reference x) {
return (const_pointer)&x;
}
size_type init_page_size() {
return max(size_type(1), size_type(4096/sizeof(T)));
}
size_type max_size() const {
return max(size_type(1), size_type(UINT_MAX/sizeof(T)));
}
};
class allocator<void> {
public:
typedef void* pointer;
};
不建議使用遭顶，性能不好晕粪，僅僅是封裝了::operator new 和 ::operator delete
這里需要使用std::alloc
