Lib/uu.py

   1 #! /usr/bin/env python
   2
   3 # Copyright 1994 by Lance Ellinghouse
   4 # Cathedral City, California Republic, United States of America.
   5 #                        All Rights Reserved
   6 # Permission to use, copy, modify, and distribute this software and its
   7 # documentation for any purpose and without fee is hereby granted,
   8 # provided that the above copyright notice appear in all copies and that
   9 # both that copyright notice and this permission notice appear in
  10 # supporting documentation, and that the name of Lance Ellinghouse
  11 # not be used in advertising or publicity pertaining to distribution
  12 # of the software without specific, written prior permission.
  13 # LANCE ELLINGHOUSE DISCLAIMS ALL WARRANTIES WITH REGARD TO
  14 # THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
  15 # FITNESS, IN NO EVENT SHALL LANCE ELLINGHOUSE CENTRUM BE LIABLE
  16 # FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  17 # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  18 # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  19 # OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  20 #
  21 # Modified by Jack Jansen, CWI, July 1995:
  22 # - Use binascii module to do the actual line-by-line conversion
  23 #   between ascii and binary. This results in a 1000-fold speedup. The C
  24 #   version is still 5 times faster, though.
  25 # - Arguments more compliant with python standard
  26
  27 """Implementation of the UUencode and UUdecode functions.
  28
  29 encode(in_file, out_file [,name, mode])
  30 decode(in_file [, out_file, mode])
  31 """
  32
  33 import binascii
  34 import os
  35 import string
  36 import sys
  37
  38 Error = 'uu.Error'
  39
  40 def encode(in_file, out_file, name=None, mode=None):
  41     """Uuencode file"""
  42     #
  43     # If in_file is a pathname open it and change defaults
  44     #
  45     if in_file == '-':
  46         in_file = sys.stdin
  47     elif type(in_file) == type(''):
  48         if name == None:
  49             name = os.path.basename(in_file)
  50         if mode == None:
  51             try:
  52                 mode = os.stat(in_file)[0]
  53             except AttributeError:
  54                 pass
  55         in_file = open(in_file, 'rb')
  56     #
  57     # Open out_file if it is a pathname
  58     #
  59     if out_file == '-':
  60         out_file = sys.stdout
  61     elif type(out_file) == type(''):
  62         out_file = open(out_file, 'w')
  63     #
  64     # Set defaults for name and mode
  65     #
  66     if name == None:
  67         name = '-'
  68     if mode == None:
  69         mode = 0666
  70     #
  71     # Write the data
  72     #
  73     out_file.write('begin %o %s\n' % ((mode&0777),name))
  74     str = in_file.read(45)
  75     while len(str) > 0:
  76         out_file.write(binascii.b2a_uu(str))
  77         str = in_file.read(45)
  78     out_file.write(' \nend\n')
  79
  80
  81 def decode(in_file, out_file=None, mode=None):
  82     """Decode uuencoded file"""
  83     #
  84     # Open the input file, if needed.
  85     #
  86     if in_file == '-':
  87         in_file = sys.stdin
  88     elif type(in_file) == type(''):
  89         in_file = open(in_file)
  90     #
  91     # Read until a begin is encountered or we've exhausted the file
  92     #
  93     while 1:
  94         hdr = in_file.readline()
  95         if not hdr:
  96             raise Error, 'No valid begin line found in input file'
  97         if hdr[:5] != 'begin':
  98             continue
  99         hdrfields = string.split(hdr)
 100         if len(hdrfields) == 3 and hdrfields[0] == 'begin':
 101             try:
 102                 string.atoi(hdrfields[1], 8)
 103                 break
 104             except ValueError:
 105                 pass
 106     if out_file == None:
 107         out_file = hdrfields[2]
 108     if mode == None:
 109         mode = string.atoi(hdrfields[1], 8)
 110     #
 111     # Open the output file
 112     #
 113     if out_file == '-':
 114         out_file = sys.stdout
 115     elif type(out_file) == type(''):
 116         fp = open(out_file, 'wb')
 117         try:
 118             os.path.chmod(out_file, mode)
 119         except AttributeError:
 120             pass
 121         out_file = fp
 122     #
 123     # Main decoding loop
 124     #
 125     s = in_file.readline()
 126     while s and s != 'end\n':
 127         try:
 128             data = binascii.a2b_uu(s)
 129         except binascii.Error, v:
 130             # Workaround for broken uuencoders by /Fredrik Lundh
 131             nbytes = (((ord(s[0])-32) & 63) * 4 + 5) / 3
 132             data = binascii.a2b_uu(s[:nbytes])
 133             sys.stderr.write("Warning: %s\n" % str(v))
 134         out_file.write(data)
 135         s = in_file.readline()
 136     if not str:
 137         raise Error, 'Truncated input file'
 138
 139 def test():
 140     """uuencode/uudecode main program"""
 141     import getopt
 142
 143     dopt = 0
 144     topt = 0
 145     input = sys.stdin
 146     output = sys.stdout
 147     ok = 1
 148     try:
 149         optlist, args = getopt.getopt(sys.argv[1:], 'dt')
 150     except getopt.error:
 151         ok = 0
 152     if not ok or len(args) > 2:
 153         print 'Usage:', sys.argv[0], '[-d] [-t] [input [output]]'
 154         print ' -d: Decode (in stead of encode)'
 155         print ' -t: data is text, encoded format unix-compatible text'
 156         sys.exit(1)
 157
 158     for o, a in optlist:
 159         if o == '-d': dopt = 1
 160         if o == '-t': topt = 1
 161
 162     if len(args) > 0:
 163         input = args[0]
 164     if len(args) > 1:
 165         output = args[1]
 166
 167     if dopt:
 168         if topt:
 169             if type(output) == type(''):
 170                 output = open(output, 'w')
 171             else:
 172                 print sys.argv[0], ': cannot do -t to stdout'
 173                 sys.exit(1)
 174         decode(input, output)
 175     else:
 176         if topt:
 177             if type(input) == type(''):
 178                 input = open(input, 'r')
 179             else:
 180                 print sys.argv[0], ': cannot do -t from stdin'
 181                 sys.exit(1)
 182         encode(input, output)
 183
 184 if __name__ == '__main__':
 185     test()