bit operations of two numbers

bit

#!/bin/bash

usage()
{
        echo "bit operations of two numbers"
        echo
        echo "Usage: $(basename $0) NUM1 OPS NUM2 [d]"
        echo "OPS: a(&, and), o(|, or), x(^, xor), l(<<, left), r(>>, right)"
        echo "d means result will be dec, default is hex"
        exit
}

if [ "$#" -lt 3 ] || [ "$#" -gt 4 ] || [[ "$2" != [aoxlr] ]]; then
        usage
fi

if [ "$4" = "d" ]; then
        echo -n "dec: "
        if [ "$2" = "a" ]; then
                printf '%d\n' "$(( $1 & $3 ))"
        elif [ "$2" = "o" ]; then
                printf '%d\n' "$(( $1 | $3 ))"
        elif [ "$2" = "x" ]; then
                printf '%d\n' "$(( $1 ^ $3 ))"
        elif [ "$2" = "l" ]; then
                printf '%d\n' "$(( $1 << $3 ))"
        elif [ "$2" = "r" ]; then
                printf '%d\n' "$(( $1 >> $3 ))"
        fi
elif [ "$4" = "" ]; then
        echo -n "hex: "
        if [ "$2" = "a" ]; then
                printf '%X\n' "$(( $1 & $3 ))"
        elif [ "$2" = "o" ]; then
                printf '%X\n' "$(( $1 | $3 ))"
        elif [ "$2" = "x" ]; then
                printf '%X\n' "$(( $1 ^ $3 ))"
        elif [ "$2" = "l" ]; then
                printf '%X\n' "$(( $1 << $3 ))"
        elif [ "$2" = "r" ]; then
                printf '%X\n' "$(( $1 >> $3 ))"
        fi
else
        usage
fi