Sun, 31 Dec 2006 19:27:23 -0500
[svn] There's now an entirely new object hierarchy for handlers, because the
number of corner cases, switches, etc. was starting to get out of hand.
This makes it easier to tell what's going on in a given case.
#!/usr/bin/env python # # x -- Intelligently extract various archive types. # Copyright (c) 2006 Brett Smith <brettcsmith@brettcsmith.org>. # # 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, 5th Floor, Boston, MA, 02111. import errno import logging import mimetypes import optparse import os import stat import subprocess import sys import tempfile from cStringIO import StringIO VERSION = "2.1" VERSION_BANNER = """x version %s Copyright (c) 2006 Brett Smith <brettcsmith@brettcsmith.org> 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.""" % (VERSION,) MATCHING_DIRECTORY = 1 # ONE_DIRECTORY = 2 BOMB = 3 EMPTY = 4 COMPRESSED = 5 mimetypes.encodings_map.setdefault('.bz2', 'bzip2') mimetypes.types_map['.exe'] = 'application/x-msdos-program' def run_command(command, description, stdout=None, stderr=None, stdin=None): process = subprocess.Popen(command, stdin=stdin, stdout=stdout, stderr=stderr) status = process.wait() for pipe in (process.stdout, process.stderr): try: pipe.close() except AttributeError: pass if status != 0: return ("%s error: '%s' returned status code %s" % (description, ' '.join(command), status)) return None class FilenameChecker(object): def __init__(self, original_name): self.original_name = original_name def is_free(self, filename=None): if filename is None: filename = self.original_name return self._is_free(filename) def _is_free(self, filename): return not os.path.exists(filename) def check(self): for suffix in [''] + ['.%s' % (x,) for x in range(1, 10)]: filename = '%s%s' % (self.original_name, suffix) if self.is_free(filename): return filename raise ValueError("all alternatives for name %s taken" % (self.original_name,)) class DirectoryChecker(FilenameChecker): def _is_free(self, filename): try: os.mkdir(filename) except OSError, error: if error.errno == errno.EEXIST: return False raise return True class ExtractorError(Exception): pass class ProcessStreamer(object): def __init__(self, command, stdin, description="checking contents", stderr=None): self.process = subprocess.Popen(command, bufsize=1, stdin=stdin, stdout=subprocess.PIPE, stderr=stderr) self.command = ' '.join(command) self.description = description def __iter__(self): return self def next(self): line = self.process.stdout.readline() if line: return line.rstrip('\n') else: raise StopIteration def stop(self): while self.process.stdout.readline(): pass self.process.stdout.close() status = self.process.wait() if status != 0: raise ExtractorError("%s error: '%s' returned status code %s" % (self.description, self.command, status)) try: self.process.stderr.close() except AttributeError: pass class BaseExtractor(object): decoders = {'bzip2': 'bzcat', 'gzip': 'zcat', 'compress': 'zcat'} name_checker = DirectoryChecker def __init__(self, filename, mimetype, encoding): if encoding and (not self.decoders.has_key(encoding)): raise ValueError("unrecognized encoding %s" % (encoding,)) self.filename = os.path.realpath(filename) self.mimetype = mimetype self.encoding = encoding self.included_archives = [] try: self.archive = open(filename, 'r') except (IOError, OSError), error: raise ExtractorError("could not open %s: %s" % (filename, error.strerror)) if encoding: self.pipe([self.decoders[encoding]], "decoding") self.prepare() def run(self, command, description="extraction", stdout=None, stderr=None, stdin=None): error = run_command(command, description, stdout, stderr, stdin) if error: raise ExtractorError(error) def pipe(self, command, description, stderr=None): output = tempfile.TemporaryFile() self.run(command, description, output, stderr, self.archive) self.archive.close() self.archive = output self.archive.flush() def prepare(self): pass def check_contents(self): archive_type = None filenames = self.get_filenames() try: filename = filenames.next() if extractor_map.has_key(mimetypes.guess_type(filename)[0]): self.included_archives.append(filename) first_part = filename.split('/', 1)[0] + '/' except StopIteration: filenames.stop() return EMPTY for filename in filenames: if extractor_map.has_key(mimetypes.guess_type(filename)[0]): self.included_archives.append(filename) if (archive_type is None) and (not filename.startswith(first_part)): archive_type = BOMB filenames.stop() if archive_type: return archive_type if self.basename() == first_part[:-1]: return MATCHING_DIRECTORY return first_part def basename(self): pieces = os.path.basename(self.filename).split('.') extension = '.' + pieces[-1] if mimetypes.encodings_map.has_key(extension): pieces.pop() extension = '.' + pieces[-1] if (mimetypes.types_map.has_key(extension) or mimetypes.common_types.has_key(extension) or mimetypes.suffix_map.has_key(extension)): pieces.pop() return '.'.join(pieces) def extract(self, path): old_path = os.path.realpath(os.curdir) os.chdir(path) self.archive.seek(0, 0) self.extract_archive() os.chdir(old_path) class TarExtractor(BaseExtractor): def get_filenames(self): self.archive.seek(0, 0) return ProcessStreamer(['tar', '-t'], self.archive) def extract_archive(self): self.run(['tar', '-x'], stdin=self.archive) class ZipExtractor(BaseExtractor): def __init__(self, filename, mimetype, encoding): self.filename = os.path.realpath(filename) self.mimetype = mimetype self.encoding = encoding self.included_archives = [] self.archive = StringIO() def get_filenames(self): self.archive.seek(0, 0) return ProcessStreamer(['zipinfo', '-1', self.filename], None) def extract_archive(self): self.run(['unzip', '-q', self.filename]) class CpioExtractor(BaseExtractor): def get_filenames(self): self.archive.seek(0, 0) return ProcessStreamer(['cpio', '-t'], self.archive, stderr=subprocess.PIPE) def extract_archive(self): self.run(['cpio', '-i', '--make-directories', '--no-absolute-filenames'], stderr=subprocess.PIPE, stdin=self.archive) class RPMExtractor(CpioExtractor): def prepare(self): self.pipe(['rpm2cpio', '-'], "rpm2cpio") def basename(self): pieces = os.path.basename(self.filename).split('.') if len(pieces) == 1: return pieces[0] elif pieces[-1] != 'rpm': return BaseExtractor.basename(self) pieces.pop() if len(pieces) == 1: return pieces[0] elif len(pieces[-1]) < 8: pieces.pop() return '.'.join(pieces) def check_contents(self): CpioExtractor.check_contents(self) return BOMB class DebExtractor(TarExtractor): def prepare(self): self.pipe(['ar', 'p', self.filename, 'data.tar.gz'], "data.tar.gz extraction") self.archive.seek(0, 0) self.pipe(['zcat'], "data.tar.gz decompression") def basename(self): pieces = os.path.basename(self.filename).split('_') if len(pieces) == 1: return pieces[0] last_piece = pieces.pop() if (len(last_piece) > 10) or (not last_piece.endswith('.deb')): return BaseExtractor.basename(self) return '_'.join(pieces) def check_contents(self): TarExtractor.check_contents(self) return BOMB class CompressionExtractor(BaseExtractor): name_checker = FilenameChecker def basename(self): pieces = os.path.basename(self.filename).split('.') extension = '.' + pieces[-1] if mimetypes.encodings_map.has_key(extension): pieces.pop() return '.'.join(pieces) def get_filenames(self): yield self.basename() def check_contents(self): return COMPRESSED def extract(self, path): output = open(path, 'w') self.run(['cat'], "output write", stdin=self.archive, stdout=output) output.close() class BaseHandler(object): def __init__(self, extractor, contents, options): self.logger = logging.getLogger('x-log') self.extractor = extractor self.contents = contents self.options = options ## def extract(self): ## raise NotImplementedError ## checker = self.extractor.name_checker(self.extractor.basename()) ## if self.options.flat: ## self.target = '.' ## return self.do_extract('.') ## elif self.options.overwrite or checker.is_free(): ## self.target = self.extractor.basename() ## return self.overwrite() ## else: ## self.target = checker.check() ## return self.safe_extract() def extract(self): try: self.extractor.extract(self.target) except ExtractorError, error: return str(error) def cleanup(self): raise NotImplementedError if self.options.flat: self.cleanup_files() else: self.cleanup_directory() def cleanup_files(self): for filename in self.extractor.get_filenames(): stat_info = os.stat(filename) perms = stat.S_IRUSR | stat.S_IWUSR if stat.S_ISDIR(stat_info.st_mode): perms |= stat.S_IXUSR os.chmod(filename, stat_info.st_mode | perms) def cleanup_directory(self): command = 'find' status = subprocess.call(['find', self.target, '-type', 'd', '-exec', 'chmod', 'u+rwx', '{}', ';']) if status == 0: command = 'chmod' status = subprocess.call(['chmod', '-R', 'u+rw', self.target]) if status != 0: return "%s returned with exit status %s" % (command, status) # The "where to extract" table, with options and archive types. # This dictates the contents of each can_handle method. # # Flat Overwrite None # File basename basename FilenameChecked # Match . . tempdir + checked # Bomb . basename DirectoryChecked class FlatHandler(BaseHandler): def can_handle(contents, options): return ((options.flat and (contents != COMPRESSED)) or (options.overwrite and (contents == MATCHING_DIRECTORY))) can_handle = staticmethod(can_handle) target = '.' cleanup = BaseHandler.cleanup_files class OverwriteHandler(BaseHandler): def can_handle(contents, options): return ((options.flat and (contents == COMPRESSED)) or (options.overwrite and (contents != MATCHING_DIRECTORY))) can_handle = staticmethod(can_handle) def __init__(self, extractor, contents, options): BaseHandler.__init__(self, extractor, contents, options) self.target = self.extractor.basename() cleanup = BaseHandler.cleanup_directory class MatchHandler(BaseHandler): def can_handle(contents, options): return contents == MATCHING_DIRECTORY can_handle = staticmethod(can_handle) def extract(self): basename = self.extractor.basename() self.target = tempfile.mkdtemp() result = BaseHandler.extract(self) if result is None: tempdir = self.target checker = self.extractor.name_checker(basename) self.target = checker.check() os.rename(os.path.join(tempdir, basename), self.target) os.rmdir(tempdir) return result cleanup = BaseHandler.cleanup_directory class EmptyHandler(object): def can_handle(contents, options): return contents == EMPTY can_handle = staticmethod(can_handle) def __init__(self, extractor, contents, options): pass def extract(self): pass def cleanup(self): pass class BombHandler(BaseHandler): def can_handle(contents, options): return True can_handle = staticmethod(can_handle) def __init__(self, extractor, contents, options): BaseHandler.__init__(self, extractor, contents, options) checker = self.extractor.name_checker(self.extractor.basename()) self.target = checker.check() cleanup = BaseHandler.cleanup_directory ## class BombHandler(BaseHandler): ## def safe_extract(self): ## return self.do_extract(self.target) ## def overwrite(self): ## self.target = self.extractor.basename() ## return self.do_extract(self.target) extractor_map = {'application/x-tar': TarExtractor, 'application/zip': ZipExtractor, 'application/x-msdos-program': ZipExtractor, 'application/x-debian-package': DebExtractor, 'application/x-redhat-package-manager': RPMExtractor, 'application/x-rpm': RPMExtractor, 'application/x-cpio': CpioExtractor} handlers = [FlatHandler, OverwriteHandler, MatchHandler, EmptyHandler, BombHandler] class ExtractorApplication(object): def __init__(self, arguments): self.parse_options(arguments) self.setup_logger() self.successes = [] self.failures = [] def parse_options(self, arguments): parser = optparse.OptionParser( usage="%prog [options] archive [archive2 ...]", description="Intelligent archive extractor", version=VERSION_BANNER ) parser.add_option('-r', '--recursive', dest='recursive', action='store_true', default=False, help='extract archives contained in the ones listed') parser.add_option('-q', '--quiet', dest='quiet', action='count', default=3, help='suppress warning/error messages') parser.add_option('-v', '--verbose', dest='verbose', action='count', default=0, help='be verbose/print debugging information') parser.add_option('-o', '--overwrite', dest='overwrite', action='store_true', default=False, help='overwrite any existing target directory') parser.add_option('-f', '--flat', '--no-directory', dest='flat', action='store_true', default=False, help="don't put contents in their own directory") ## parser.add_option('-n', '--noninteractive', dest='batch', ## action='store_true', default=False, ## help="don't ask how to handle special cases") self.options, filenames = parser.parse_args(arguments) if not filenames: parser.error("you did not list any archives") self.archives = {os.path.realpath(os.curdir): filenames} def setup_logger(self): self.logger = logging.getLogger('x-log') handler = logging.StreamHandler() # WARNING is the default. handler.setLevel(10 * (self.options.quiet - self.options.verbose)) formatter = logging.Formatter("x: %(levelname)s: %(message)s") handler.setFormatter(formatter) self.logger.addHandler(handler) def get_extractor(self): mimetype, encoding = mimetypes.guess_type(self.current_filename) try: extractor = extractor_map[mimetype] except KeyError: if encoding: extractor = CompressionExtractor contents = COMPRESSED else: return "not a known archive type" try: self.current_extractor = extractor(self.current_filename, mimetype, encoding) content = self.current_extractor.check_contents() for handler in handlers: if handler.can_handle(content, self.options): self.current_handler = handler(self.current_extractor, content, self.options) break except ExtractorError, error: return str(error) def recurse(self): if not self.options.recursive: return for filename in self.current_extractor.included_archives: tail_path, basename = os.path.split(filename) directory = os.path.join(self.current_directory, self.current_handler.target, tail_path) self.archives.setdefault(directory, []).append(basename) def report(self, function, *args): error = function(*args) if error: self.logger.error("%s: %s", self.current_filename, error) return False return True def run(self): while self.archives: self.current_directory, filenames = self.archives.popitem() for filename in filenames: os.chdir(self.current_directory) self.current_filename = filename self.cleanup_actions = [] success = self.report(self.get_extractor) if success: for name in 'extract', 'cleanup': success = (self.report(getattr(self.current_handler, name)) and success) self.recurse() if success: self.successes.append(self.current_filename) else: self.failures.append(self.current_filename) if self.failures: return 1 return 0 if __name__ == '__main__': app = ExtractorApplication(sys.argv[1:]) sys.exit(app.run())