We have investigated adsorption of a hard-sphere fluid in a slitlike pore with composite walls that permit penetration of fluid particles into the wall body for a given depth. Each of the walls is prepared by quenching of a layer of an ideal gas on a hard wall substrate. Our interest is in the adsorption isotherms and in partitioning of the fluid between random microporous layers of a given thickness and an empty space between these layers. The inhomogeneous replica Ornstein-Zernike equations and the Percus-Yevick approximation in conjunction with the Born-Green-Yvon equation for the density profile are used to study the system. The theoretical predictions are compared with the grand canonical ensemble Monte Carlo simulations. The adsorption isotherms and in-plane correlation functions are evaluated and compared with the reference system. We have shown that the presence of random matrix layers deposited on the pore walls significantly influences the structure of the confined fluid. The adsorption isotherms reflect decreasing penetrability of the fluid into a pore with microporous walls. In-plane correlations for two particles located at a rough wall are stronger than the correlations at a hard wall.