#ifndef KSTD_ALLOCATOR_H_
#define KSTD_ALLOCATOR_H_// 这个头文件包含一个模板类 allocator，用于管理内存的分配、释放，对象的构造、析构
// 暂不支持标准库容器 todo::支持萃取#include <new>      // placement new
#include <cstddef>  // ptrdiff_t size_t
#include <cstdlib>  // exit
#include <climits>  // UINT_MAX
#include <iostream> // cerrnamespace kstd
{/*new 处理函数set_new_handler()是为分配函数在凡是内存分配尝试失败时调用的函数。其目的是三件事之一：1) 令更多内存可用2) 终止程序（例如通过调用 std::terminate3) 抛出 std::bad_alloc 或自 std::bad_alloc 导出的类型的异常。*///创建内存template <class T>inline T *_allocate(ptrdiff_t size, T *){// set_new_handler(0);// there are no arguments to ‘set_new_handler’// that depend on a template parameter, so a declaration of//‘set_new_handler’ must be available [-fpermissive]T *tmp = (T *)(::operator new((size_t)(size * sizeof(T))));if (!tmp){std::cerr << "out of memory" << std::endl;exit(1);}return tmp;}//销毁内存template <class T>inline void _deallocate(T *buffer){::operator delete(buffer);}//构造函数 placement newtemplate <class T1, class T2>inline void _construct(T1 *p, const T2 &value){new (p) T1(value);}template <class T>inline void _construct(T* ptr){new (ptr) T;}//析构template <class T>inline void _destroy(T *ptr){ptr->~T();}// 模板类：allocator// 模板函数代表数据类型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;public:static pointer allocate(size_type n, const void *hint = 0){return _allocate((difference_type)n, (pointer)0);}static void deallocate(pointer ptr);static void construct(pointer ptr, const_reference value);static void construct(pointer ptr);static void destroy(pointer ptr);};template <class T>void allocator<T>::deallocate(pointer ptr){_deallocate(ptr);}template <class T>void allocator<T>::construct(pointer ptr, const_reference value){_construct(ptr, value);}template <class T>void allocator<T>::construct(pointer ptr){_construct(ptr);}template <class T>void allocator<T>::destroy(pointer ptr){_destroy(ptr);}} // namespace kstd
#endif // KSTD_ALLOCATOR_H_