flexible bruteforcer skeleton in Golang

bruteforce.go

package main

import "fmt"

type state struct {
	digit    [2]int
	negative bool
}

const MAX_NUMBER = 16

// returns a function that manipulates the digit at given pos
func digitManipulator(pos int) func(*state) bool {
	return func(s *state) bool {
		s.digit[pos]++
		if s.digit[pos] == MAX_NUMBER {
			s.digit[pos] = 0
			return true
		}
		return false
	}
}

func manipulateNegative(s *state) bool {
	s.negative = !s.negative

	// stop when negative once again becomes false
	return !s.negative
}

// controls the order in which state is manipulated
var stateManipulators = []func(*state) bool{
	digitManipulator(1), // 2nd digit
	digitManipulator(0), // 1st digit
	manipulateNegative,  // sign
}

// manipulates the state
func nextState(s *state) bool {
	i := 0
	for ; i < len(stateManipulators); i++ {
		if !stateManipulators[i](s) {
			break
		}
	}

	return i == len(stateManipulators)
}

func stateFormatter(s *state) string {
	const c = "0123456789abcdef"
	sign := ""
	if s.negative {
		sign = "-"
	}
	return sign + string(c[s.digit[0]]) + string(c[s.digit[1]])
}

func main() {
	s := &state{} // initial state

	for {
		//fmt.Printf("%v\n", s)
		fmt.Println(stateFormatter(s))
		if nextState(s) {
			break
		}
	}

	fmt.Println("finished.")
}