Пример #1
0
/**
 * [[DefineOwnProperty]] ecma array object's operation
 *
 * See also:
 *          ECMA-262 v5, 8.6.2; ECMA-262 v5, Table 8
 *          ECMA-262 v5, 15.4.5.1
 *
 * @return ecma value
 *         Returned value must be freed with ecma_free_value
 */
ecma_value_t
ecma_op_array_object_define_own_property (ecma_object_t *object_p, /**< the array object */
                                          ecma_string_t *property_name_p, /**< property name */
                                          const ecma_property_descriptor_t *property_desc_p, /**< property descriptor */
                                          bool is_throw) /**< flag that controls failure handling */
{
  if (ecma_string_is_length (property_name_p))
  {
    if (!property_desc_p->is_value_defined)
    {
      return ecma_op_general_object_define_own_property (object_p, property_name_p, property_desc_p, is_throw);
    }

    JERRY_ASSERT (property_desc_p->is_configurable_defined || !property_desc_p->is_configurable);
    JERRY_ASSERT (property_desc_p->is_enumerable_defined || !property_desc_p->is_enumerable);
    JERRY_ASSERT (property_desc_p->is_writable_defined || !property_desc_p->is_writable);

    uint32_t flags = 0;

    if (is_throw)
    {
      flags |= ECMA_ARRAY_OBJECT_SET_LENGTH_FLAG_IS_THROW;
    }

    /* Only the writable and data properties can be modified. */
    if (property_desc_p->is_configurable
        || property_desc_p->is_enumerable
        || property_desc_p->is_get_defined
        || property_desc_p->is_set_defined)
    {
      flags |= ECMA_ARRAY_OBJECT_SET_LENGTH_FLAG_REJECT;
    }

    if (property_desc_p->is_writable_defined)
    {
      flags |= ECMA_ARRAY_OBJECT_SET_LENGTH_FLAG_WRITABLE_DEFINED;
    }

    if (property_desc_p->is_writable)
    {
      flags |= ECMA_ARRAY_OBJECT_SET_LENGTH_FLAG_WRITABLE;
    }

    return ecma_op_array_object_set_length (object_p, property_desc_p->value, flags);
  }

  uint32_t index = ecma_string_get_array_index (property_name_p);

  if (index == ECMA_STRING_NOT_ARRAY_INDEX)
  {
    return ecma_op_general_object_define_own_property (object_p, property_name_p, property_desc_p, is_throw);
  }

  ecma_string_t magic_string_length;
  ecma_init_ecma_length_string (&magic_string_length);

  ecma_property_t *len_prop_p = ecma_find_named_property (object_p, &magic_string_length);
  JERRY_ASSERT (len_prop_p != NULL
                && ECMA_PROPERTY_GET_TYPE (*len_prop_p) == ECMA_PROPERTY_TYPE_NAMEDDATA);

  ecma_property_value_t *len_prop_value_p = ECMA_PROPERTY_VALUE_PTR (len_prop_p);

  bool update_length = (index >= ecma_get_uint32_from_value (len_prop_value_p->value));

  if (update_length && !ecma_is_property_writable (*len_prop_p))
  {
    return ecma_reject (is_throw);
  }

  ecma_value_t completition = ecma_op_general_object_define_own_property (object_p,
                                                                          property_name_p,
                                                                          property_desc_p,
                                                                          false);
  JERRY_ASSERT (ecma_is_value_boolean (completition));

  if (ecma_is_value_false (completition))
  {
    return ecma_reject (is_throw);
  }

  if (update_length)
  {
    ecma_value_assign_uint32 (&len_prop_value_p->value, index + 1);
  }
  return ecma_make_simple_value (ECMA_SIMPLE_VALUE_TRUE);
} /* ecma_op_array_object_define_own_property */
Пример #2
0
/**
 * If the property's name is one of built-in properties of the object
 * that is not instantiated yet, instantiate the property and
 * return pointer to the instantiated property.
 *
 * @return pointer property, if one was instantiated,
 *         NULL - otherwise.
 */
ecma_property_t *
ecma_builtin_try_to_instantiate_property (ecma_object_t *object_p, /**< object */
                                          ecma_string_t *string_p) /**< property's name */
{
  JERRY_ASSERT (ecma_get_object_is_builtin (object_p));

  ecma_extended_object_t *ext_obj_p = (ecma_extended_object_t *) object_p;

  if (ecma_get_object_type (object_p) == ECMA_OBJECT_TYPE_FUNCTION
      && ecma_builtin_function_is_routine (object_p))
  {
    if (ecma_string_is_length (string_p))
    {
      /*
       * Lazy instantiation of 'length' property
       *
       * Note:
       *      We don't need to mark that the property was already lazy instantiated,
       *      as it is non-configurable and so can't be deleted
       */

      ecma_property_t *len_prop_p = ecma_create_named_data_property (object_p,
                                                                     string_p,
                                                                     ECMA_PROPERTY_FIXED);

      ecma_set_named_data_property_value (len_prop_p,
                                          ecma_make_integer_value (ext_obj_p->u.built_in.length));

      JERRY_ASSERT (!ecma_is_property_configurable (len_prop_p));
      return len_prop_p;
    }

    return NULL;
  }

  lit_magic_string_id_t magic_string_id;

  if (!ecma_is_string_magic (string_p, &magic_string_id))
  {
    return NULL;
  }

  ecma_builtin_id_t builtin_id = (ecma_builtin_id_t) ext_obj_p->u.built_in.id;

  JERRY_ASSERT (builtin_id < ECMA_BUILTIN_ID__COUNT);
  JERRY_ASSERT (ecma_builtin_is (object_p, builtin_id));

  const ecma_builtin_property_descriptor_t *property_list_p = ecma_builtin_property_list_references[builtin_id];

  const ecma_builtin_property_descriptor_t *curr_property_p = property_list_p;

  while (curr_property_p->magic_string_id != magic_string_id)
  {
    if (curr_property_p->magic_string_id == LIT_MAGIC_STRING__COUNT)
    {
      return NULL;
    }
    curr_property_p++;
  }

  uint32_t index = (uint32_t) (curr_property_p - property_list_p);

  JERRY_ASSERT (index < 64);

  if (likely (index < 32))
  {
    uint32_t bit_for_index = (uint32_t) 1u << index;

    if (ext_obj_p->u.built_in.instantiated_bitset & bit_for_index)
    {
      /* This property was instantiated before. */
      return NULL;
    }

    ext_obj_p->u.built_in.instantiated_bitset |= bit_for_index;
  }
  else
  {
    uint32_t bit_for_index = (uint32_t) 1u << (index - 32);
    ecma_value_t *mask_prop_p = ecma_find_internal_property (object_p,
                                                             ECMA_INTERNAL_PROPERTY_INSTANTIATED_MASK_32_63);

    uint32_t instantiated_bitset;

    if (mask_prop_p == NULL)
    {
      mask_prop_p = ecma_create_internal_property (object_p, ECMA_INTERNAL_PROPERTY_INSTANTIATED_MASK_32_63);
      instantiated_bitset = 0;
    }
    else
    {
      instantiated_bitset = *mask_prop_p;

      if (instantiated_bitset & bit_for_index)
      {
        /* This property was instantiated before. */
        return NULL;
      }
    }

    *mask_prop_p = (instantiated_bitset | bit_for_index);
  }

  ecma_value_t value = ecma_make_simple_value (ECMA_SIMPLE_VALUE_EMPTY);

  switch (curr_property_p->type)
  {
    case ECMA_BUILTIN_PROPERTY_SIMPLE:
    {
      value = ecma_make_simple_value (curr_property_p->value);
      break;
    }
    case ECMA_BUILTIN_PROPERTY_NUMBER:
    {
      ecma_number_t num = 0.0;

      if (curr_property_p->value < ECMA_BUILTIN_NUMBER_MAX)
      {
        num = curr_property_p->value;
      }
      else if (curr_property_p->value < ECMA_BUILTIN_NUMBER_NAN)
      {
        static const ecma_number_t builtin_number_list[] =
        {
          ECMA_NUMBER_MAX_VALUE,
          ECMA_NUMBER_MIN_VALUE,
          ECMA_NUMBER_E,
          ECMA_NUMBER_PI,
          ECMA_NUMBER_LN10,
          ECMA_NUMBER_LN2,
          ECMA_NUMBER_LOG2E,
          ECMA_NUMBER_LOG10E,
          ECMA_NUMBER_SQRT2,
          ECMA_NUMBER_SQRT_1_2
        };

        num = builtin_number_list[curr_property_p->value - ECMA_BUILTIN_NUMBER_MAX];
      }
      else
      {
        switch (curr_property_p->value)
        {
          case ECMA_BUILTIN_NUMBER_NAN:
          {
            num = ecma_number_make_nan ();
            break;
          }
          case ECMA_BUILTIN_NUMBER_POSITIVE_INFINITY:
          {
            num = ecma_number_make_infinity (false);
            break;
          }
          case ECMA_BUILTIN_NUMBER_NEGATIVE_INFINITY:
          {
            num = ecma_number_make_infinity (true);
            break;
          }
          default:
          {
            JERRY_UNREACHABLE ();
            break;
          }
        }
      }

      value = ecma_make_number_value (num);
      break;
    }
    case ECMA_BUILTIN_PROPERTY_STRING:
    {
      value = ecma_make_string_value (ecma_get_magic_string (curr_property_p->value));
      break;
    }
    case ECMA_BUILTIN_PROPERTY_OBJECT:
    {
      value = ecma_make_object_value (ecma_builtin_get (curr_property_p->value));
      break;
    }
    case ECMA_BUILTIN_PROPERTY_ROUTINE:
    {
      ecma_object_t *func_obj_p;
      func_obj_p = ecma_builtin_make_function_object_for_routine (builtin_id,
                                                                  ECMA_GET_ROUTINE_ID (curr_property_p->value),
                                                                  ECMA_GET_ROUTINE_LENGTH (curr_property_p->value));
      value = ecma_make_object_value (func_obj_p);
      break;
    }
    default:
    {
      JERRY_UNREACHABLE ();
      return NULL;
    }
  }

  ecma_property_t *prop_p = ecma_create_named_data_property (object_p,
                                                             string_p,
                                                             curr_property_p->attributes);

  ecma_set_named_data_property_value (prop_p, value);

  /* Reference count of objects must be decreased. */
  if (ecma_is_value_object (value))
  {
    ecma_free_value (value);
  }

  return prop_p;
} /* ecma_builtin_try_to_instantiate_property */