Module to convert a mail message to or from quoted-printable. The
message may consist of several MIME parts in which case each part is
converted independent of the others. Only converts when necessary.
diff --git a/Lib/mimify.py b/Lib/mimify.py
new file mode 100755
index 0000000..1582199
--- /dev/null
+++ b/Lib/mimify.py
@@ -0,0 +1,415 @@
+#!/usr/local/bin/python
+
+'''Mimification and unmimification of mail messages.
+
+decode quoted-printable parts of a mail message or encode using
+quoted-printable.
+
+Usage:
+ mimify(input, output)
+ unmimify(input, output)
+to encode and decode respectively. Input and output may be the name
+of a file or an open file object. Only a readline() method is used
+on the input file, only a write() method is used on the output file.
+When using file names, the input and output file names may be the
+same.
+
+Interactive usage:
+ mimify.py -e [infile [outfile]]
+ mimify.py -d [infile [outfile]]
+to encode and decode respectively. Infile defaults to standard
+input and outfile to standard output.
+'''
+
+# Configure
+MAXLEN = 200 # if lines longer than this, encode as quoted-printable
+CHARSET = 'ISO-8859-1' # default charset for non-US-ASCII mail
+QUOTE = '> ' # string replies are quoted with
+# End configure
+
+import regex, regsub, string
+
+qp = regex.compile('^content-transfer-encoding:[\000-\377]*quoted-printable',
+ regex.casefold)
+mp = regex.compile('^content-type:[\000-\377]*multipart/[\000-\377]*boundary="?\\([^;"\n]*\\)',
+ regex.casefold)
+chrset = regex.compile('^\\(content-type:.*charset="\\)\\(us-ascii\\|iso-8859-[0-9]+\\)\\("[\000-\377]*\\)',
+ regex.casefold)
+he = regex.compile('^-*$')
+mime_code = regex.compile('=\\([0-9a-f][0-9a-f]\\)', regex.casefold)
+mime_head = regex.compile('=\\?iso-8859-1\\?q\\?\\([^?]+\\)\\?=',
+ regex.casefold)
+repl = regex.compile('^subject:[ \t]+re: ', regex.casefold)
+
+class File:
+ '''A simple fake file object that knows about limited
+ read-ahead and boundaries.
+ The only supported method is readline().'''
+
+ def __init__(self, file, boundary):
+ self.file = file
+ self.boundary = boundary
+ self.peek = None
+
+ def readline(self):
+ if self.peek is not None:
+ return ''
+ line = self.file.readline()
+ if not line:
+ return line
+ if self.boundary:
+ if line == self.boundary + '\n':
+ self.peek = line
+ return ''
+ if line == self.boundary + '--\n':
+ self.peek = line
+ return ''
+ return line
+
+class HeaderFile:
+ def __init__(self, file):
+ self.file = file
+ self.peek = None
+
+ def readline(self):
+ if self.peek is not None:
+ line = self.peek
+ self.peek = None
+ else:
+ line = self.file.readline()
+ if not line:
+ return line
+ if he.match(line) >= 0:
+ return line
+ while 1:
+ self.peek = self.file.readline()
+ if len(self.peek) == 0 or \
+ (self.peek[0] != ' ' and self.peek[0] != '\t'):
+ return line
+ line = line + self.peek
+ self.peek = None
+
+def mime_decode(line):
+ '''Decode a single line of quoted-printable text to 8bit.'''
+ newline = ''
+ while 1:
+ i = mime_code.search(line)
+ if i < 0:
+ break
+ newline = newline + line[:i] + \
+ chr(string.atoi(mime_code.group(1), 16))
+ line = line[i+3:]
+ return newline + line
+
+def mime_decode_header(line):
+ '''Decode a header line to 8bit.'''
+ newline = ''
+ while 1:
+ i = mime_head.search(line)
+ if i < 0:
+ break
+ match = mime_head.group(0, 1)
+ newline = newline + line[:i] + mime_decode(match[1])
+ line = line[i + len(match[0]):]
+ return newline + line
+
+def unmimify_part(ifile, ofile):
+ '''Convert a quoted-printable part of a MIME mail message to 8bit.'''
+ multipart = None
+ quoted_printable = 0
+ is_repl = 0
+ if ifile.boundary and ifile.boundary[:2] == QUOTE:
+ prefix = QUOTE
+ else:
+ prefix = ''
+
+ # read header
+ hfile = HeaderFile(ifile)
+ while 1:
+ line = hfile.readline()
+ if not line:
+ return
+ if prefix and line[:len(prefix)] == prefix:
+ line = line[len(prefix):]
+ pref = prefix
+ else:
+ pref = ''
+ line = mime_decode_header(line)
+ if qp.match(line) >= 0:
+ quoted_printable = 1
+ continue # skip this header
+ ofile.write(pref + line)
+ if not prefix and repl.match(line) >= 0:
+ # we're dealing with a reply message
+ is_repl = 1
+ if mp.match(line) >= 0:
+ multipart = '--' + mp.group(1)
+ if he.match(line) >= 0:
+ break
+ if is_repl and (quoted_printable or multipart):
+ is_repl = 0
+
+ # read body
+ while 1:
+ line = ifile.readline()
+ if not line:
+ return
+ line = regsub.gsub(mime_head, '\\1', line)
+ if prefix and line[:len(prefix)] == prefix:
+ line = line[len(prefix):]
+ pref = prefix
+ else:
+ pref = ''
+## if is_repl and len(line) >= 4 and line[:4] == QUOTE+'--' and line[-3:] != '--\n':
+## multipart = line[:-1]
+ while multipart:
+ if line == multipart + '--\n':
+ ofile.write(pref + line)
+ multipart = None
+ line = None
+ break
+ if line == multipart + '\n':
+ ofile.write(pref + line)
+ nifile = File(ifile, multipart)
+ unmimify_part(nifile, ofile)
+ line = nifile.peek
+ continue
+ # not a boundary between parts
+ break
+ if line and quoted_printable:
+ while line[-2:] == '=\n':
+ line = line[:-2]
+ newline = ifile.readline()
+ if newline[:len(QUOTE)] == QUOTE:
+ newline = newline[len(QUOTE):]
+ line = line + newline
+ line = mime_decode(line)
+ if line:
+ ofile.write(pref + line)
+
+def unmimify(infile, outfile):
+ '''Convert quoted-printable parts of a MIME mail message to 8bit.'''
+ if type(infile) == type(''):
+ ifile = open(infile)
+ if type(outfile) == type('') and infile == outfile:
+ import os
+ d, f = os.path.split(infile)
+ os.rename(infile, os.path.join(d, ',' + f))
+ else:
+ ifile = infile
+ if type(outfile) == type(''):
+ ofile = open(outfile, 'w')
+ else:
+ ofile = outfile
+ nifile = File(ifile, None)
+ unmimify_part(nifile, ofile)
+ ofile.flush()
+
+mime_char = regex.compile('[=\240-\377]') # quote these chars in body
+mime_header_char = regex.compile('[=?\240-\377]') # quote these in header
+
+def mime_encode(line, header):
+ '''Code a single line as quoted-printable.
+ If header is set, quote some extra characters.'''
+ if header:
+ reg = mime_header_char
+ else:
+ reg = mime_char
+ newline = ''
+ if len(line) >= 5 and line[:5] == 'From ':
+ # quote 'From ' at the start of a line for stupid mailers
+ newline = string.upper('=%02x' % ord('F'))
+ line = line[1:]
+ while 1:
+ i = reg.search(line)
+ if i < 0:
+ break
+ newline = newline + line[:i] + \
+ string.upper('=%02x' % ord(line[i]))
+ line = line[i+1:]
+ line = newline + line
+
+ newline = ''
+ while len(line) >= 75:
+ i = 73
+ while line[i] == '=' or line[i-1] == '=':
+ i = i - 1
+ i = i + 1
+ newline = newline + line[:i] + '=\n'
+ line = line[i:]
+ return newline + line
+
+mime_header = regex.compile('\\([ \t(]\\)\\([-a-zA-Z0-9_+]*[\240-\377][-a-zA-Z0-9_+\240-\377]*\\)\\([ \t)]\\|$\\)')
+
+def mime_encode_header(line):
+ '''Code a single header line as quoted-printable.'''
+ newline = ''
+ while 1:
+ i = mime_header.search(line)
+ if i < 0:
+ break
+ newline = newline + line[:i] + mime_header.group(1) + \
+ '=?' + CHARSET + '?Q?' + \
+ mime_encode(mime_header.group(2), 1) + \
+ '?=' + mime_header.group(3)
+ line = line[i+len(mime_header.group(0)):]
+ return newline + line
+
+mv = regex.compile('^mime-version:', regex.casefold)
+cte = regex.compile('^content-transfer-encoding:', regex.casefold)
+iso_char = regex.compile('[\240-\377]')
+
+def mimify_part(ifile, ofile, is_mime):
+ '''Convert an 8bit part of a MIME mail message to quoted-printable.'''
+ has_cte = is_qp = 0
+ multipart = None
+ must_quote_body = must_quote_header = has_iso_chars = 0
+
+ header = []
+ header_end = ''
+ message = []
+ message_end = ''
+ # read header
+ hfile = HeaderFile(ifile)
+ while 1:
+ line = hfile.readline()
+ if not line:
+ break
+ if not must_quote_header and iso_char.search(line) >= 0:
+ must_quote_header = 1
+ if mv.match(line) >= 0:
+ is_mime = 1
+ if cte.match(line) >= 0:
+ has_cte = 1
+ if qp.match(line) >= 0:
+ is_qp = 1
+ if mp.match(line) >= 0:
+ multipart = '--' + mp.group(1)
+ if he.match(line) >= 0:
+ header_end = line
+ break
+ header.append(line)
+
+ # read body
+ while 1:
+ line = ifile.readline()
+ if not line:
+ break
+ if multipart:
+ if line == multipart + '--\n':
+ message_end = line
+ break
+ if line == multipart + '\n':
+ message_end = line
+ break
+ if is_qp:
+ while line[-2:] == '=\n':
+ line = line[:-2]
+ newline = ifile.readline()
+ if newline[:len(QUOTE)] == QUOTE:
+ newline = newline[len(QUOTE):]
+ line = line + newline
+ line = mime_decode(line)
+ message.append(line)
+ if not has_iso_chars:
+ if iso_char.search(line) >= 0:
+ has_iso_chars = must_quote_body = 1
+ if not must_quote_body:
+ if len(line) > MAXLEN:
+ must_quote_body = 1
+
+ # convert and output header and body
+ for line in header:
+ if must_quote_header:
+ line = mime_encode_header(line)
+ if chrset.match(line) >= 0:
+ if has_iso_chars:
+ # change us-ascii into iso-8859-1
+ if string.lower(chrset.group(2)) == 'us-ascii':
+ line = chrset.group(1) + \
+ CHARSET + chrset.group(3)
+ else:
+ # change iso-8859-* into us-ascii
+ line = chrset.group(1) + 'us-ascii' + chrset.group(3)
+ if has_cte and cte.match(line) >= 0:
+ line = 'Content-Transfer-Encoding: '
+ if must_quote_body:
+ line = line + 'quoted-printable\n'
+ else:
+ line = line + '7bit\n'
+ ofile.write(line)
+ if (must_quote_header or must_quote_body) and not is_mime:
+ ofile.write('Mime-Version: 1.0\n')
+ ofile.write('Content-Type: text/plain; ')
+ if has_iso_chars:
+ ofile.write('charset="%s"\n' % CHARSET)
+ else:
+ ofile.write('charset="us-ascii"\n')
+ if must_quote_body and not has_cte:
+ ofile.write('Content-Transfer-Encoding: quoted-printable\n')
+ ofile.write(header_end)
+
+ for line in message:
+ if must_quote_body:
+ line = mime_encode(line, 0)
+ ofile.write(line)
+ ofile.write(message_end)
+
+ line = message_end
+ while multipart:
+ if line == multipart + '--\n':
+ return
+ if line == multipart + '\n':
+ nifile = File(ifile, multipart)
+ mimify_part(nifile, ofile, 1)
+ line = nifile.peek
+ ofile.write(line)
+ continue
+
+def mimify(infile, outfile):
+ '''Convert 8bit parts of a MIME mail message to quoted-printable.'''
+ if type(infile) == type(''):
+ ifile = open(infile)
+ if type(outfile) == type('') and infile == outfile:
+ import os
+ d, f = os.path.split(infile)
+ os.rename(infile, os.path.join(d, ',' + f))
+ else:
+ ifile = infile
+ if type(outfile) == type(''):
+ ofile = open(outfile, 'w')
+ else:
+ ofile = outfile
+ nifile = File(ifile, None)
+ mimify_part(nifile, ofile, 0)
+ ofile.flush()
+
+import sys
+if __name__ == '__main__' or (len(sys.argv) > 0 and sys.argv[0] == 'mimify'):
+ import getopt
+ usage = 'Usage: mimify [-l len] -[ed] [infile [outfile]]'
+
+ opts, args = getopt.getopt(sys.argv[1:], 'l:ed')
+ if len(args) not in (0, 1, 2):
+ print usage
+ sys.exit(1)
+ if (('-e', '') in opts) == (('-d', '') in opts):
+ print usage
+ sys.exit(1)
+ for o, a in opts:
+ if o == '-e':
+ encode = mimify
+ elif o == '-d':
+ encode = unmimify
+ elif o == '-l':
+ try:
+ MAXLEN = string.atoi(a)
+ except:
+ print usage
+ sys.exit(1)
+ if len(args) == 0:
+ encode(sys.stdin, sys.stdout)
+ elif len(args) == 1:
+ encode(args[0], sys.stdout)
+ else:
+ encode(args[0], args[1])