use Config::Std;
use Readonly;
Readonly my $DEFAULT_LOG_LEVEL   => q{warn};
Readonly my $DEFAULT_LOG_FILE    => $PROGRAM_NAME . q{.log};
Readonly my $DEFAULT_CONFIG_FILE => $PROGRAM_NAME . q{.cfg};
read_config $DEFAULT_CONFIG_FILE => my %config;

use Log::StdLog {
    level => ($config{'log'}{'level'} || $DEFAULT_LOG_LEVEL), 
    file  => ($config{'log'}{'file' } || $DEFAULT_LOG_FILE )
};