summaryrefslogtreecommitdiff
path: root/Lib/uu.py
blob: 9b1e5e607207f789deec21efa1a19fb8a5f7a788 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
#! /usr/bin/env python3

# Copyright 1994 by Lance Ellinghouse
# Cathedral City, California Republic, United States of America.
#                        All Rights Reserved
# Permission to use, copy, modify, and distribute this software and its
# documentation for any purpose and without fee is hereby granted,
# provided that the above copyright notice appear in all copies and that
# both that copyright notice and this permission notice appear in
# supporting documentation, and that the name of Lance Ellinghouse
# not be used in advertising or publicity pertaining to distribution
# of the software without specific, written prior permission.
# LANCE ELLINGHOUSE DISCLAIMS ALL WARRANTIES WITH REGARD TO
# THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
# FITNESS, IN NO EVENT SHALL LANCE ELLINGHOUSE CENTRUM BE LIABLE
# FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#
# Modified by Jack Jansen, CWI, July 1995:
# - Use binascii module to do the actual line-by-line conversion
#   between ascii and binary. This results in a 1000-fold speedup. The C
#   version is still 5 times faster, though.
# - Arguments more compliant with python standard

"""Implementation of the UUencode and UUdecode functions.

encode(in_file, out_file [,name, mode], *, backtick=False)
decode(in_file [, out_file, mode, quiet])
"""

import binascii
import os
import sys

__all__ = ["Error", "encode", "decode"]

class Error(Exception):
    pass

def encode(in_file, out_file, name=None, mode=None, *, backtick=False):
    """Uuencode file"""
    #
    # If in_file is a pathname open it and change defaults
    #
    opened_files = []
    try:
        if in_file == '-':
            in_file = sys.stdin.buffer
        elif isinstance(in_file, str):
            if name is None:
                name = os.path.basename(in_file)
            if mode is None:
                try:
                    mode = os.stat(in_file).st_mode
                except AttributeError:
                    pass
            in_file = open(in_file, 'rb')
            opened_files.append(in_file)
        #
        # Open out_file if it is a pathname
        #
        if out_file == '-':
            out_file = sys.stdout.buffer
        elif isinstance(out_file, str):
            out_file = open(out_file, 'wb')
            opened_files.append(out_file)
        #
        # Set defaults for name and mode
        #
        if name is None:
            name = '-'
        if mode is None:
            mode = 0o666
        #
        # Write the data
        #
        out_file.write(('begin %o %s\n' % ((mode & 0o777), name)).encode("ascii"))
        data = in_file.read(45)
        while len(data) > 0:
            out_file.write(binascii.b2a_uu(data, backtick=backtick))
            data = in_file.read(45)
        if backtick:
            out_file.write(b'`\nend\n')
        else:
            out_file.write(b' \nend\n')
    finally:
        for f in opened_files:
            f.close()


def decode(in_file, out_file=None, mode=None, quiet=False):
    """Decode uuencoded file"""
    #
    # Open the input file, if needed.
    #
    opened_files = []
    if in_file == '-':
        in_file = sys.stdin.buffer
    elif isinstance(in_file, str):
        in_file = open(in_file, 'rb')
        opened_files.append(in_file)

    try:
        #
        # Read until a begin is encountered or we've exhausted the file
        #
        while True:
            hdr = in_file.readline()
            if not hdr:
                raise Error('No valid begin line found in input file')
            if not hdr.startswith(b'begin'):
                continue
            hdrfields = hdr.split(b' ', 2)
            if len(hdrfields) == 3 and hdrfields[0] == b'begin':
                try:
                    int(hdrfields[1], 8)
                    break
                except ValueError:
                    pass
        if out_file is None:
            # If the filename isn't ASCII, what's up with that?!?
            out_file = hdrfields[2].rstrip(b' \t\r\n\f').decode("ascii")
            if os.path.exists(out_file):
                raise Error('Cannot overwrite existing file: %s' % out_file)
        if mode is None:
            mode = int(hdrfields[1], 8)
        #
        # Open the output file
        #
        if out_file == '-':
            out_file = sys.stdout.buffer
        elif isinstance(out_file, str):
            fp = open(out_file, 'wb')
            os.chmod(out_file, mode)
            out_file = fp
            opened_files.append(out_file)
        #
        # Main decoding loop
        #
        s = in_file.readline()
        while s and s.strip(b' \t\r\n\f') != b'end':
            try:
                data = binascii.a2b_uu(s)
            except binascii.Error as v:
                # Workaround for broken uuencoders by /Fredrik Lundh
                nbytes = (((s[0]-32) & 63) * 4 + 5) // 3
                data = binascii.a2b_uu(s[:nbytes])
                if not quiet:
                    sys.stderr.write("Warning: %s\n" % v)
            out_file.write(data)
            s = in_file.readline()
        if not s:
            raise Error('Truncated input file')
    finally:
        for f in opened_files:
            f.close()

def test():
    """uuencode/uudecode main program"""

    import optparse
    parser = optparse.OptionParser(usage='usage: %prog [-d] [-t] [input [output]]')
    parser.add_option('-d', '--decode', dest='decode', help='Decode (instead of encode)?', default=False, action='store_true')
    parser.add_option('-t', '--text', dest='text', help='data is text, encoded format unix-compatible text?', default=False, action='store_true')

    (options, args) = parser.parse_args()
    if len(args) > 2:
        parser.error('incorrect number of arguments')
        sys.exit(1)

    # Use the binary streams underlying stdin/stdout
    input = sys.stdin.buffer
    output = sys.stdout.buffer
    if len(args) > 0:
        input = args[0]
    if len(args) > 1:
        output = args[1]

    if options.decode:
        if options.text:
            if isinstance(output, str):
                output = open(output, 'wb')
            else:
                print(sys.argv[0], ': cannot do -t to stdout')
                sys.exit(1)
        decode(input, output)
    else:
        if options.text:
            if isinstance(input, str):
                input = open(input, 'rb')
            else:
                print(sys.argv[0], ': cannot do -t from stdin')
                sys.exit(1)
        encode(input, output)

if __name__ == '__main__':
    test()