#!/bin/sh

# This script translates any text into a sequence of hex ASCII codes.

# usual dd/sh intro

PATH=''
dd=/bin/dd
rm=/bin/rm
tmp=/tmp/ascii2hex.$$
trap "$rm -f $tmp.?" 0 1 2 3

false () { return 1 }
true () { return 0 }

# ASCII conversion table

conv09='	'
conv20=' '
conv21='!'
conv22='"'
conv23='#'
conv24='$'
conv25='%'
conv26='&'
conv27="'"
conv28='('
conv29=')'
conv2A='*'
conv2B='+'
conv2C=','
conv2D='-'
conv2E='.'
conv2F='/'
conv30='0'
conv31='1'
conv32='2'
conv33='3'
conv34='4'
conv35='5'
conv36='6'
conv37='7'
conv38='8'
conv39='9'
conv3A=':'
conv3B=';'
conv3C='<'
conv3D='='
conv3E='>'
conv3F='?'
conv40='@'
conv41='A'
conv42='B'
conv43='C'
conv44='D'
conv45='E'
conv46='F'
conv47='G'
conv48='H'
conv49='I'
conv4A='J'
conv4B='K'
conv4C='L'
conv4D='M'
conv4E='N'
conv4F='O'
conv50='P'
conv51='Q'
conv52='R'
conv53='S'
conv54='T'
conv55='U'
conv56='V'
conv57='W'
conv58='X'
conv59='Y'
conv5A='Z'
conv5B='['
conv5C='\'
conv5D=']'
conv5E='^'
conv5F='_'
conv60='`'
conv61='a'
conv62='b'
conv63='c'
conv64='d'
conv65='e'
conv66='f'
conv67='g'
conv68='h'
conv69='i'
conv6A='j'
conv6B='k'
conv6C='l'
conv6D='m'
conv6E='n'
conv6F='o'
conv70='p'
conv71='q'
conv72='r'
conv73='s'
conv74='t'
conv75='u'
conv76='v'
conv77='w'
conv78='x'
conv79='y'
conv7A='z'
conv7B='{'
conv7C='|'
conv7D='}'
conv7E='~'

# create two conversion functions

hex_to_char () {
    eval char='$'conv$1
}

char_to_hex () {
    # I never said anywhere it needs to be fast
    for upper in 0 1 2 3 4 5 6 7
    do
    	for lower in 0 1 2 3 4 5 6 7 8 9 A B C D E F
	do
	    eval char='$'conv$upper$lower
	    case "$char" in
	    	"$1") hex=$upper$lower; return ;;
	    esac
	done
    done
    hex=00
}

# read the text
go=true
while $go
do
    len="`$dd bs=1 count=1 of=$tmp.a 2>&1`"
    case "$len" in
	0*) go=false ;;
	*) char="`$dd if=$tmp.a bs=1 count=1 2>/dev/null`"
	     case "$char" in
		 ?) char_to_hex "$char" ;;
		 *) hex=0A ;;
	     esac
	     echo $hex
	     ;;
    esac
done