Machine controller and machine control method

The machine controller includes: an engine rotation speed increase amount determination section for calculating an amount of increase in an engine speed produced by the first firing of a machine after a restart condition is satisfied; a start failure determination crank-angle change amount determination value setting section for setting a restart failure determination threshold based on the size of the increase in the engine speed; and a restart error determination section for determining a restart error when a crank angle change amount from a first ignition timing of the engine is greater after the satisfaction of the restart condition as the restart error determination threshold, even though a complete combustion of the engine is not determined interrupting a restart operation of the machine, and restarting the restart operation of the engine after a predetermined time period.