C语言实现的基本操作——栈

#define ERROR 0
#define TRUE 1
#define FALSE 0
#define OK 1
#define EQUAL 1
#define OVERFLOW -1
#define STACK_INIT_SIZE 100   //存储空间初始化分配量
#define STACKINCREMENT 10     //存储空间分配增量

typedef int Status;

typedef struct
{
  SElemType *base;
  SElemType *top;  //栈顶指针
  int stacksize;
}SqStack,*pSqStack;

Status InitStack(SqStack  **S);  //初始化
Status DestroyStack(SqStack *S);
Status ClearStack(SqStack *S);
Status StackEmpty(SqStack S); //判断栈是否为空
int StackLength(SqStack S); //返回栈的长度
Status GetTop(SqStack S,SElemType *e); //用e返回栈顶元素
Status Push(SqStack *S,SElemType e);  //向栈订插入元素
Status Pop(SqStack *S,SElemType *e); //出栈
Status StackTraverse(SqStack S,Status (*visit)());  //从栈底到栈顶对栈S中每个元素调用函数visit()

Status InitStack(SqStack **S)
{
  (*S)=(SqStack *)malloc(sizeof(SqStack));
  (*S)->base=(SElemType *)malloc(STACK_INIT_SIZE *sizeof(SElemType));
  if(!(*S)->base)exit(OVERFLOW);
  (*S)->top=(*S)->base;
  (*S)->stacksize=STACK_INIT_SIZE;
  return OK;
}

Status DestroyStack(SqStack *S)
{
 free(S->base);
 free(S);
}

Status ClearStack(SqStack *S)
{
  S->top=S->base;
}

Status StackEmpty(SqStack S)
{
  if(S.top==S.base) return TRUE;
  else
    return FALSE;
}

int StackLength(SqStack S)
{
  int i;
  SElemType *p;
  i=0;
  p=S.top;
  while(p!=S.base)
    {p++;
     i++;
    }
}

Status GetTop(SqStack S,SElemType *e)
{
  if(S.top==S.base) return ERROR;
  *e=*(S.top-1);
  return OK;
}

Status Push(SqStack *S,SElemType e)
{
  if(S->top - S->base>=S->stacksize)
   { S->base=(SElemType *) realloc(S->base,
    (S->stacksize + STACKINCREMENT) * sizeof(SElemType));
     if(!S->base)exit(OVERFLOW);
     S->top=S->base+S->stacksize;
     S->stacksize += STACKINCREMENT;
   }
  *(S->top++)=e;
  return OK;
}

Status Pop(SqStack *S,SElemType *e)
{
  if(S->top==S->base) return ERROR;
  *e=*--S->top;
  return OK;
}

Status StackTraverse(SqStack S,Status (*visit)())
{
  while(S.top!=S.base)
     visit(*(--S.top));
}