#ifndef _STACK_H_#define _STACK_H_#define STACK_INITIAL_SIZE	256/* Do NOT manipulate the __stack structure directly unless you know what * you are doning. */struct __stack{	char *base;	char *top;	char *end;};typedef struct __stack stack_t;#define stack_push(type, elem, stack) \({															\	(stack)->top + sizeof (type) <= (stack)->end ||			\	__stack_expand(sizeof (type), stack) >= 0 ?				\		*(type *)(stack)->top = (elem),						\		(stack)->top += sizeof (type),						\		(stack)->top - (stack)->base : -1;					\})#define stack_pop(type, stack)	(*(type *)((stack)->top -= sizeof (type)))/*#define stack_push(type, elem, stack) \({																			\	(stack)->top + sizeof (type) <= (stack)->end ||							\		__stack_expand(sizeof (type), stack) >= 0 ?							\	*((type *)(stack)->top)++ = (elem), (stack)->top - (stack)->base : -1;	\})#define stack_pop(type, stack)	(*--(type *)(stack)->top)*/#define stack_top(type, stack)	(*((type *)(stack)->top - 1))#define stack_height(stack)		((stack)->top - (stack)->base)#define stack_empty(stack)		((stack)->base == (stack)->top)#ifdef __cplusplusextern "C"{#endifstack_t *stack_create(unsigned int init_size);void stack_destroy(stack_t *stack);/* Never call the following function directly. */int __stack_expand(unsigned int elem_size, stack_t *stack);#ifdef __cplusplus}#endif#endif