hex

#! /usr/bin/python
# vim: set fileencoding=utf-8 tabstop=4 shiftwidth=4 :
# hex (Python script) -- Print decoded hex string
#
# Version:   1.0
# Copyright: (c)2018 Alastair Irvine <alastair@plug.org.au>
# Keywords:  hex decode
# Notice:    
# Licence:   This file is released under the GNU General Public License
#
'''Description: Decodes the command-line parameter, or stdin
  
Usage:   hex [ -n | -s <sep> ] [ <string> ]
Options:
  
'''
# Licence details:
#     This program is free software; you can redistribute it and/or modify
#     it under the terms of the GNU General Public License as published by
#     the Free Software Foundation; either version 2 of the License, or (at
#     your option) any later version.
#
#     See http://www.gnu.org/licenses/gpl-2.0.html for more information.
#
#     You can find the complete text of the GPLv2 in the file
#     /usr/share/common-licenses/GPL-2 on Debian systems.
#     Or see the file COPYING in the same directory as this program.
#
#
# TO-DO:
#   + special last-line handling for sep

from __future__ import print_function
import sys
import getopt
import sys, binascii


self="hex"
allowed_options='hdns:'
allowed_long_options=['help', 'nosep', 'sep=']


# *** CLASSES ***

# *** FUNCTIONS ***
def show_help(dest=sys.stdout):
    print(__doc__.rstrip(), file=dest)


def report_error(msg):
    print(self + ": Error: " + msg, file=sys.stderr)


def report_warning(msg):
    print(self + ": Warning: " + msg, file=sys.stderr)


def report_notice(msg):
    print(self + ": Notice: " + msg, file=sys.stderr)


def process(source, sep = None):
    for line in source:
        if sep is False or sep is None:
            print(binascii.unhexlify(line))
        else:
            print(binascii.unhexlify(line), end=sep)


# *** MAINLINE ***
if __name__ == '__main__':
    # == Command-line parsing ==
    # -- defaults --
    debug = 0

    # -- option handling --
    try:
        optlist, args = getopt.getopt(sys.argv[1:], allowed_options, allowed_long_options)
    except getopt.GetoptError as e:
        report_error(e)
        sys.exit(1)

    # Create a special dict object that defaults to False for unspecified options
    from collections import defaultdict
    params = defaultdict(bool)

    for option, opt_arg in optlist:
        if option in ("--nosep", "-n"):
            params["sep"] = ""
        elif option in ("--sep", "-s"):
            params["sep"] = opt_arg
        elif option == "-d":
            debug += 1
        elif option == "-h" or option == "--help":
            show_help()
            sys.exit(0)

    # -- argument checking --
    ## if len(args) not in (2, 3):
    ##     report_error("Invalid command-line parameters.")
    ##     print("", file=sys.stderr)
    ##     show_help(sys.stderr)
    ##     sys.exit(1)

    # -- argument handling --
    if len(args) == 0:
        source = (l.rstrip() for l in sys.stdin)
    else:
        source = iter(args)

    process(source, params["sep"])