stack_vm/stack.c

62 lines
956 B
C

#include "./stack.h"
stack_t *stack_new(int size, int *result)
{
stack_t *stack = (stack_t *)malloc(sizeof(stack_t));
if (stack == NULL)
{
*result = -1;
return *result;
}
stack->mem = (int *)malloc(sizeof(int) * size);
if (stack->mem == NULL)
{
*result = -1;
return *result;
}
stack->size = size;
stack->cursor = -1;
return stack;
}
int stack_push(stack_t *stack, int value, int *result)
{
if (stack->cursor > stack->size - 1)
{
*result = 2;
return *result;
}
stack->mem[stack->cursor + 1] = value;
stack->cursor++;
return 0;
}
int stack_pop(stack_t *stack, int *result)
{
if (stack->cursor == -1)
{
*result = 1;
return *result;
}
int value = stack->mem[stack->cursor];
stack->cursor--;
return value;
}
int stack_get(stack_t *stack, int pos, int *result)
{
if (pos < 0 || pos >= stack->size)
{
*result = 1;
return *result;
}
return stack->mem[pos];
}