#! /usr/bin/python3 # Copyright (C) 2001-2023 by the Free Software Foundation, Inc. # # 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. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, # USA. """Clean up an .mbox archive file. The archiver looks for Unix-From lines separating messages in an mbox archive file. For compatibility, it specifically looks for lines that start with "From " -- i.e. the letters capital-F, lowercase-r, o, m, space, ignoring everything else on the line. Normally, any lines that start "From " in the body of a message should be escaped such that a > character is actually the first on a line. It is possible though that body lines are not actually escaped. This script attempts to fix these by doing a stricter test of the Unix-From lines. Any lines that start "From " but do not pass this stricter test are escaped with a > character. This in an enhanced version of the standard cleanarch script. It works just like the normal cleanarch but it also looks at lines that look like Date: headers and if they don't have a parseable date close to that of the Unix-from, it replaces the value with the date from the Unix-From. Usage: cleanarch3 [options] inputfile Options: -s n --status=n Print a # character every n messages processed -o file --output=file Write the output mailbox to file. If not specified, stdout is used. -d n --date-skew n n is the number of hours difference between the time in the Date: header and that in the Unix-from within which the Date: header will be accepted as is and not replaced with the Unix-from time. Default is 24 hours. -e encoding --encoding=encoding Specify the character encoding of the input and output files if other than utf-8. -q / --quiet Don't print changed line information to standard error. -n / --dry-run Don't actually output anything. -h / --help Print this message and exit """ import getopt import re import sys import time from email.utils import formatdate, parsedate _fromlinepattern = 'From \\s*[^\\s]+\\s+\\w\\w\\w\\s+\\w\\w\\w\\s+\\d?\\d\\s+\\d?\\d:\\d\\d(:\\d\\d)?(\\s+[^\\s]+)?\\s+\\d\\d\\d\\d\\s*[^\\s]*\\s*$' cre = re.compile(_fromlinepattern) # From RFC 2822, a header field name must contain only characters from 33-126 # inclusive, excluding colon. I.e. from oct 41 to oct 176 less oct 072. fre = re.compile(r'^[\041-\071\073-\176]+:') def usage(code, msg=''): if code: fd = sys.stderr else: fd = sys.stdout print(__doc__, file=fd) if msg: print(msg, file=fd) sys.exit(code) def escape_line(line, lineno, quiet, output, ofile): if output: ofile.write('>' + line) if not quiet: print('Unix-From line changed: {}'.format(lineno), file=sys.stderr) print(line[:-1], file=sys.stderr) def check_date(line, lastfrom, lineno, date_skew, quiet, output): lfdate = parsedate(re.sub(r'^From \s*\S+\s+', '', lastfrom, flags=re.I)) ddate = parsedate(re.sub(r'^Date:\s*', '', line, flags=re.I)) if ddate: try: dsecs = time.mktime(ddate) except (OverflowError, ValueError): dsecs = 0 else: dsecs = 0 # lfdate should be good because it looks like a valid unixfrom lfsecs = time.mktime(lfdate) if abs(dsecs - lfsecs) <= date_skew: if output: sys.stdout.write(line) return # Date: is off. Replace it with unix from date newline = 'Date: ' + formatdate(lfsecs) + '\n' if output: sys.stdout.write(newline) if not quiet: print(f'Date: changed at line {lineno}\n{line}{newline}', file=sys.stderr), def main(): inheader = False try: opts, args = getopt.getopt( sys.argv[1:], 'hqns:o:e:d:', ['help', 'quiet', 'dry-run', 'status=', 'output=', 'encoding=', 'date-skew=']) except getopt.error as msg: usage(1, msg) quiet = False output = True status = -1 oname = '-' encoding = 'utf-8' date_skew = 24 * 60 * 60 for opt, arg in opts: if opt in ('-h', '--help'): usage(0) elif opt in ('-q', '--quiet'): quiet = True elif opt in ('-n', '--dry-run'): output = False elif opt in ('-s', '--status'): try: status = int(arg) except ValueError: usage(1, 'Bad status number: {}'.format(arg)) elif opt in ('-e', '--encoding'): encoding = arg elif opt in ('-o', '--output'): oname = arg elif opt in ('-d', '--date-skew'): try: date_skew = int(arg) * 60 * 60 except ValueError: usage(1, 'Bad date-skew number: {}'.format(arg)) if len(args) == 0: usage(1, 'Input file required') if len(args) > 1: usage(1, 'Only one input file allowed') input = open(args[0], encoding=encoding) if oname == '-': ofile = sys.stdout else: ofile = open(oname, 'w', encoding=encoding) lineno = 0 statuscnt = 0 messages = 0 prevline = None while True: lineno += 1 line = input.readline() if not line: break if line.startswith('From '): if cre.match(line): # This is a real Unix-From line. But it could be a message # /about/ Unix-From lines, so as a second order test, make # sure there's at least one RFC 2822 header following nextline = input.readline() lineno += 1 if not nextline: # It was the last line of the mbox, so it couldn't have # been a Unix-From escape_line(line, lineno, quiet, output, ofile) break fieldname = nextline.split(':', 1) if len(fieldname) < 2 or not fre.match(nextline): # The following line was not a header, so this wasn't a # valid Unix-From escape_line(line, lineno, quiet, output, ofile) if output: ofile.write(nextline) else: # It's a valid Unix-From line messages += 1 lastfrom = line inheader = True if output: # Before we spit out the From_ line, make sure the # previous line was blank. if prevline is not None and prevline != '\n': ofile.write('\n') ofile.write(line) ofile.write(nextline) if status > 0 and (messages % status) == 0: sys.stderr.write('#') statuscnt += 1 if statuscnt > 50: print(file=sys.stderr) statuscnt = 0 else: # This is a bogus Unix-From line escape_line(line, lineno, quiet, output, ofile) else: # Any old line if inheader and line.lower().startswith('date:'): check_date(line, lastfrom, lineno, date_skew, quiet, output) elif output: ofile.write(line) if not line.strip(): inheader = False prevline = line print('{} messages found'.format(messages), file=sys.stderr) if __name__ == '__main__': main()