5 stack_grow(struct stack *st, size_t new_size)
9 if (st->asize >= new_size)
12 new_st = realloc(st->item, new_size * sizeof(void *));
16 memset(new_st + st->asize, 0x0,
17 (new_size - st->asize) * sizeof(void *));
22 if (st->size > new_size)
29 stack_free(struct stack *st)
42 stack_init(struct stack *st, size_t initial_size)
51 return stack_grow(st, initial_size);
55 stack_pop(struct stack *st)
60 return st->item[--st->size];
64 stack_push(struct stack *st, void *item)
66 if (stack_grow(st, st->size * 2) < 0)
69 st->item[st->size++] = item;
74 stack_top(struct stack *st)
79 return st->item[st->size - 1];