unix2dos.py {unix2dos|dos2unix} {dirname|filename}

#! /usr/bin/env python
# coding=utf-8
 
import os
import sys
 
try:
  input = raw_input
except:
  pass
 
def usage():
  print('Usage:')
  print('\t %s' % ('unix2dos.py {unix2dos|dos2unix} {dirname|filename}'))
 
def err_exit(msg):
  if msg: print('%s' % msg)
  usage()
  sys.exit(0)
 
def getfiles(root):
  for dirpath, dirnames, filenames in os.walk(root):
    for filename in filenames:
      yield os.path.join(dirpath, filename)
 
def format_file(file, toformat='unix2dos'):
  print('Formatting %s:\t%s' % (toformat, file))
  if not os.path.isfile(file):
    print('ERROR: %s invalid normal file' % file)
    return
  if toformat == 'unix2dos':
    line_sep = '\r\n'
  else:
    line_sep = '\n'
  with open(file, 'r') as fd:
    tmpfile = open(file+toformat, 'w+b')
    for line in fd:
      line = line.replace('\r', '')
      line = line.replace('\n', '')
      tmpfile.write(line+line_sep)
    tmpfile.close()
    os.rename(file+toformat, file)
 
def uni_format_proc(filename, toformat):
  if not toformat or toformat not in ['unix2dos', 'dos2unix']:
    err_exit('ERROR: %s: Invalid format param' % (toformat))
  if not filename or not os.path.exists(filename):
    err_exit('ERROR: %s: No such file or directory' % (filename))
  if os.path.isfile(filename):
    format_file(filename, toformat)
    return
  if os.path.isdir(filename):
    for file in getfiles(filename):
      uni_format_proc(file, toformat)
 
if __name__ == '__main__':
  if len(sys.argv) != 3:
    err_exit('ERROR: Invalid arguments')
  uni_format_proc(filename=sys.argv[2], toformat=sys.argv[1])