Python os.stat() Examples

def mounts(self, detectdev=False):
        mounts = []
        with open('/proc/mounts', 'r') as f:
            for line in f:
                dev, path, fstype = line.split()[0:3]
                if fstype in ('ext2', 'ext3', 'ext4', 'xfs',
                              'jfs', 'reiserfs', 'btrfs',
                              'simfs'): # simfs: filesystem in OpenVZ
                    if not os.path.isdir(path): continue
                    mounts.append({'dev': dev, 'path': path, 'fstype': fstype})
        for mount in mounts:
            stat = os.statvfs(mount['path'])
            total = stat.f_blocks*stat.f_bsize
            free = stat.f_bfree*stat.f_bsize
            used = (stat.f_blocks-stat.f_bfree)*stat.f_bsize
            mount['total'] = b2h(total)
            mount['free'] = b2h(free)
            mount['used'] = b2h(used)
            mount['used_rate'] = div_percent(used, total)
            if detectdev:
                dev = os.stat(mount['path']).st_dev
                mount['major'], mount['minor'] = os.major(dev), os.minor(dev)
        return mounts 

def _warn_unsafe_extraction_path(path):
        """
        If the default extraction path is overridden and set to an insecure
        location, such as /tmp, it opens up an opportunity for an attacker to
        replace an extracted file with an unauthorized payload. Warn the user
        if a known insecure location is used.

        See Distribute #375 for more details.
        """
        if os.name == 'nt' and not path.startswith(os.environ['windir']):
            # On Windows, permissions are generally restrictive by default
            #  and temp directories are not writable by other users, so
            #  bypass the warning.
            return
        mode = os.stat(path).st_mode
        if mode & stat.S_IWOTH or mode & stat.S_IWGRP:
            msg = ("%s is writable by group/others and vulnerable to attack "
                "when "
                "used with get_resource_filename. Consider a more secure "
                "location (set with .set_extraction_path or the "
                "PYTHON_EGG_CACHE environment variable)." % path)
            warnings.warn(msg, UserWarning) 

def copy_from_host(module):
    compress = module.params.get('compress')
    src = module.params.get('src')

    if not os.path.exists(src):
        module.fail_json(msg="file not found: {}".format(src))
    if not os.access(src, os.R_OK):
        module.fail_json(msg="file is not readable: {}".format(src))

    mode = oct(os.stat(src).st_mode & 0o777)

    with open(src, 'rb') as f:
        raw_data = f.read()

    sha1 = hashlib.sha1(raw_data).hexdigest()
    data = zlib.compress(raw_data) if compress else raw_data

    module.exit_json(content=base64.b64encode(data), sha1=sha1, mode=mode,
                     source=src) 

def check_is_readonly(self, fname):
        """
        Return `True` if @fname is read-only on the filesystem.

        @fname
          Path to a file.
        """
        if not fname:
            return

        try:
            mode = os.stat(fname)
            read_only = (stat.S_IMODE(mode.st_mode) & stat.S_IWUSR != stat.S_IWUSR)
        except FileNotFoundError:
            return

        return read_only 

def place_data_on_block_device(blk_device, data_src_dst):
    """Migrate data in data_src_dst to blk_device and then remount."""
    # mount block device into /mnt
    mount(blk_device, '/mnt')
    # copy data to /mnt
    copy_files(data_src_dst, '/mnt')
    # umount block device
    umount('/mnt')
    # Grab user/group ID's from original source
    _dir = os.stat(data_src_dst)
    uid = _dir.st_uid
    gid = _dir.st_gid
    # re-mount where the data should originally be
    # TODO: persist is currently a NO-OP in core.host
    mount(blk_device, data_src_dst, persist=True)
    # ensure original ownership of new mount.
    os.chown(data_src_dst, uid, gid) 

def copyfile(src, dst):
    """Copy data from src to dst"""
    if _samefile(src, dst):
        raise Error("`%s` and `%s` are the same file" % (src, dst))

    for fn in [src, dst]:
        try:
            st = os.stat(fn)
        except OSError:
            # File most likely does not exist
            pass
        else:
            # XXX What about other special files? (sockets, devices...)
            if stat.S_ISFIFO(st.st_mode):
                raise SpecialFileError("`%s` is a named pipe" % fn)

    with open(src, 'rb') as fsrc:
        with open(dst, 'wb') as fdst:
            copyfileobj(fsrc, fdst) 

def newer(self, source, target):
        """Tell if the target is newer than the source.

        Returns true if 'source' exists and is more recently modified than
        'target', or if 'source' exists and 'target' doesn't.

        Returns false if both exist and 'target' is the same age or younger
        than 'source'. Raise PackagingFileError if 'source' does not exist.

        Note that this test is not very accurate: files created in the same
        second will have the same "age".
        """
        if not os.path.exists(source):
            raise DistlibException("file '%r' does not exist" %
                                   os.path.abspath(source))
        if not os.path.exists(target):
            return True

        return os.stat(source).st_mtime > os.stat(target).st_mtime 

def postprocess(self, tempname, filename):
        """Perform any platform-specific postprocessing of `tempname`

        This is where Mac header rewrites should be done; other platforms don't
        have anything special they should do.

        Resource providers should call this method ONLY after successfully
        extracting a compressed resource.  They must NOT call it on resources
        that are already in the filesystem.

        `tempname` is the current (temporary) name of the file, and `filename`
        is the name it will be renamed to by the caller after this routine
        returns.
        """

        if os.name == 'posix':
            # Make the resource executable
            mode = ((os.stat(tempname).st_mode) | 0o555) & 0o7777
            os.chmod(tempname, mode) 

def _warn_unsafe_extraction_path(path):
        """
        If the default extraction path is overridden and set to an insecure
        location, such as /tmp, it opens up an opportunity for an attacker to
        replace an extracted file with an unauthorized payload. Warn the user
        if a known insecure location is used.

        See Distribute #375 for more details.
        """
        if os.name == 'nt' and not path.startswith(os.environ['windir']):
            # On Windows, permissions are generally restrictive by default
            #  and temp directories are not writable by other users, so
            #  bypass the warning.
            return
        mode = os.stat(path).st_mode
        if mode & stat.S_IWOTH or mode & stat.S_IWGRP:
            msg = ("%s is writable by group/others and vulnerable to attack "
                "when "
                "used with get_resource_filename. Consider a more secure "
                "location (set with .set_extraction_path or the "
                "PYTHON_EGG_CACHE environment variable)." % path)
            warnings.warn(msg, UserWarning) 

def postprocess(self, tempname, filename):
        """Perform any platform-specific postprocessing of `tempname`

        This is where Mac header rewrites should be done; other platforms don't
        have anything special they should do.

        Resource providers should call this method ONLY after successfully
        extracting a compressed resource.  They must NOT call it on resources
        that are already in the filesystem.

        `tempname` is the current (temporary) name of the file, and `filename`
        is the name it will be renamed to by the caller after this routine
        returns.
        """

        if os.name == 'posix':
            # Make the resource executable
            mode = ((os.stat(tempname).st_mode) | 0o555) & 0o7777
            os.chmod(tempname, mode) 

def unpack_and_compile(self, egg_path, destination):
        to_compile = []
        to_chmod = []

        def pf(src, dst):
            if dst.endswith('.py') and not src.startswith('EGG-INFO/'):
                to_compile.append(dst)
            elif dst.endswith('.dll') or dst.endswith('.so'):
                to_chmod.append(dst)
            self.unpack_progress(src, dst)
            return not self.dry_run and dst or None

        unpack_archive(egg_path, destination, pf)
        self.byte_compile(to_compile)
        if not self.dry_run:
            for f in to_chmod:
                mode = ((os.stat(f)[stat.ST_MODE]) | 0o555) & 0o7755
                chmod(f, mode) 

def commonprefix(m):
    "Given a list of pathnames, returns the longest common leading component"
    if not m: return ''
    # Some people pass in a list of pathname parts to operate in an OS-agnostic
    # fashion; don't try to translate in that case as that's an abuse of the
    # API and they are already doing what they need to be OS-agnostic and so
    # they most likely won't be using an os.PathLike object in the sublists.
    if not isinstance(m[0], (list, tuple)):
        m = tuple(map(os.fspath, m))
    s1 = min(m)
    s2 = max(m)
    for i, c in enumerate(s1):
        if c != s2[i]:
            return s1[:i]
    return s1

# Are two stat buffers (obtained from stat, fstat or lstat)
# describing the same file? 

def serve(self, request, path):
        # the following code is largely borrowed from `django.views.static.serve`
        # and django-filetransfers: filetransfers.backends.default
        fullpath = os.path.join(settings.PRIVATE_MEDIA_ROOT, path)
        if not os.path.exists(fullpath):
            raise Http404('"{0}" does not exist'.format(fullpath))
        # Respect the If-Modified-Since header.
        statobj = os.stat(fullpath)
        content_type = mimetypes.guess_type(fullpath)[0] or 'application/octet-stream'
        if not was_modified_since(request.META.get('HTTP_IF_MODIFIED_SINCE'),
                                  statobj[stat.ST_MTIME], statobj[stat.ST_SIZE]):
            return HttpResponseNotModified(content_type=content_type)
        response = HttpResponse(open(fullpath, 'rb').read(), content_type=content_type)
        response["Last-Modified"] = http_date(statobj[stat.ST_MTIME])
        # filename = os.path.basename(path)
        # response['Content-Disposition'] = smart_str(u'attachment; filename={0}'.format(filename))
        return response 

def copyfile(src, dst):
    """Copy data from src to dst"""
    if _samefile(src, dst):
        raise Error("`%s` and `%s` are the same file" % (src, dst))

    for fn in [src, dst]:
        try:
            st = os.stat(fn)
        except OSError:
            # File most likely does not exist
            pass
        else:
            # XXX What about other special files? (sockets, devices...)
            if stat.S_ISFIFO(st.st_mode):
                raise SpecialFileError("`%s` is a named pipe" % fn)

    with open(src, 'rb') as fsrc:
        with open(dst, 'wb') as fdst:
            copyfileobj(fsrc, fdst) 

def _warn_unsafe_extraction_path(path):
        """
        If the default extraction path is overridden and set to an insecure
        location, such as /tmp, it opens up an opportunity for an attacker to
        replace an extracted file with an unauthorized payload. Warn the user
        if a known insecure location is used.

        See Distribute #375 for more details.
        """
        if os.name == 'nt' and not path.startswith(os.environ['windir']):
            # On Windows, permissions are generally restrictive by default
            #  and temp directories are not writable by other users, so
            #  bypass the warning.
            return
        mode = os.stat(path).st_mode
        if mode & stat.S_IWOTH or mode & stat.S_IWGRP:
            msg = ("%s is writable by group/others and vulnerable to attack "
                "when "
                "used with get_resource_filename. Consider a more secure "
                "location (set with .set_extraction_path or the "
                "PYTHON_EGG_CACHE environment variable)." % path)
            warnings.warn(msg, UserWarning) 

def postprocess(self, tempname, filename):
        """Perform any platform-specific postprocessing of `tempname`

        This is where Mac header rewrites should be done; other platforms don't
        have anything special they should do.

        Resource providers should call this method ONLY after successfully
        extracting a compressed resource.  They must NOT call it on resources
        that are already in the filesystem.

        `tempname` is the current (temporary) name of the file, and `filename`
        is the name it will be renamed to by the caller after this routine
        returns.
        """

        if os.name == 'posix':
            # Make the resource executable
            mode = ((os.stat(tempname).st_mode) | 0o555) & 0o7777
            os.chmod(tempname, mode) 

def postprocess(self, tempname, filename):
        """Perform any platform-specific postprocessing of `tempname`

        This is where Mac header rewrites should be done; other platforms don't
        have anything special they should do.

        Resource providers should call this method ONLY after successfully
        extracting a compressed resource.  They must NOT call it on resources
        that are already in the filesystem.

        `tempname` is the current (temporary) name of the file, and `filename`
        is the name it will be renamed to by the caller after this routine
        returns.
        """

        if os.name == 'posix':
            # Make the resource executable
            mode = ((os.stat(tempname).st_mode) | 0o555) & 0o7777
            os.chmod(tempname, mode) 

def unpack_and_compile(self, egg_path, destination):
        to_compile = []
        to_chmod = []

        def pf(src, dst):
            if dst.endswith('.py') and not src.startswith('EGG-INFO/'):
                to_compile.append(dst)
            elif dst.endswith('.dll') or dst.endswith('.so'):
                to_chmod.append(dst)
            self.unpack_progress(src, dst)
            return not self.dry_run and dst or None

        unpack_archive(egg_path, destination, pf)
        self.byte_compile(to_compile)
        if not self.dry_run:
            for f in to_chmod:
                mode = ((os.stat(f)[stat.ST_MODE]) | 0o555) & 0o7755
                chmod(f, mode) 

def place_data_on_block_device(blk_device, data_src_dst):
    """Migrate data in data_src_dst to blk_device and then remount."""
    # mount block device into /mnt
    mount(blk_device, '/mnt')
    # copy data to /mnt
    copy_files(data_src_dst, '/mnt')
    # umount block device
    umount('/mnt')
    # Grab user/group ID's from original source
    _dir = os.stat(data_src_dst)
    uid = _dir.st_uid
    gid = _dir.st_gid
    # re-mount where the data should originally be
    # TODO: persist is currently a NO-OP in core.host
    mount(blk_device, data_src_dst, persist=True)
    # ensure original ownership of new mount.
    os.chown(data_src_dst, uid, gid) 

def place_data_on_block_device(blk_device, data_src_dst):
    """Migrate data in data_src_dst to blk_device and then remount."""
    # mount block device into /mnt
    mount(blk_device, '/mnt')
    # copy data to /mnt
    copy_files(data_src_dst, '/mnt')
    # umount block device
    umount('/mnt')
    # Grab user/group ID's from original source
    _dir = os.stat(data_src_dst)
    uid = _dir.st_uid
    gid = _dir.st_gid
    # re-mount where the data should originally be
    # TODO: persist is currently a NO-OP in core.host
    mount(blk_device, data_src_dst, persist=True)
    # ensure original ownership of new mount.
    os.chown(data_src_dst, uid, gid) 

def _write_symlink(self, zf, link_target, link_path):
        """Package symlinks with appropriate zipfile metadata."""
        info = zipfile.ZipInfo()
        info.filename = link_path
        info.create_system = 3
        # Magic code for symlinks / py2/3 compat
        # 27166663808 = (stat.S_IFLNK | 0755) << 16
        info.external_attr = 2716663808
        zf.writestr(info, link_target) 

def Send_File_Client():
    sendSock = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
    sendSock.connect(ADDR)

    fhead=struct.pack('IdI',1,float(time.time()),os.stat(filename).st_size)
    print(fhead)
    sendSock.send(fhead)
    fp = open(filename,'rb')

    while 1:
        filedata = fp.read(BUFSIZE)
        if not filedata: 
            break
        sendSock.send(filedata)
    
    '''
    print u"?????????????...\n"

    fp.close()
    sendSock.close()
    print u"?????...\n" 

    ''' 

def maybe_download_and_extract():
  """Download and extract the tarball from Alex's website."""
  dest_directory = FLAGS.data_dir
  if not os.path.exists(dest_directory):
    os.makedirs(dest_directory)
  filename = DATA_URL.split('/')[-1]
  filepath = os.path.join(dest_directory, filename)
  if not os.path.exists(filepath):
    def _progress(count, block_size, total_size):
      sys.stdout.write('\r>> Downloading %s %.1f%%' % (filename,
          float(count * block_size) / float(total_size) * 100.0))
      sys.stdout.flush()
    filepath, _ = urllib.request.urlretrieve(DATA_URL, filepath,
                                             reporthook=_progress)
    print()
    statinfo = os.stat(filepath)
    print('Successfully downloaded', filename, statinfo.st_size, 'bytes.')
    tarfile.open(filepath, 'r:gz').extractall(dest_directory) 

def maybe_download_and_extract():
  """Download and extract the tarball from Alex's website."""
  dest_directory = FLAGS.data_dir
  if not os.path.exists(dest_directory):
    os.makedirs(dest_directory)
  filename = DATA_URL.split('/')[-1]
  filepath = os.path.join(dest_directory, filename)
  if not os.path.exists(filepath):
    def _progress(count, block_size, total_size):
      sys.stdout.write('\r>> Downloading %s %.1f%%' % (filename,
          float(count * block_size) / float(total_size) * 100.0))
      sys.stdout.flush()
    filepath, _ = urllib.request.urlretrieve(DATA_URL, filepath,
                                             reporthook=_progress)
    print()
    statinfo = os.stat(filepath)
    print('Successfully downloaded', filename, statinfo.st_size, 'bytes.')
    tarfile.open(filepath, 'r:gz').extractall(dest_directory) 

def checkcache(filename=None):
    """Discard cache entries that are out of date.
    (This is not checked upon each call!)"""

    if filename is None:
        filenames = cache.keys()
    else:
        if filename in cache:
            filenames = [filename]
        else:
            return

    for filename in filenames:
        size, mtime, lines, fullname = cache[filename]
        if mtime is None:
            continue   # no-op for files loaded via a __loader__
        try:
            stat = os.stat(fullname)
        except os.error:
            del cache[filename]
            continue
        if size != stat.st_size or mtime != stat.st_mtime:
            del cache[filename] 

def newer(source, target):
    """Tells if the target is newer than the source.

    Return true if 'source' exists and is more recently modified than
    'target', or if 'source' exists and 'target' doesn't.

    Return false if both exist and 'target' is the same age or younger
    than 'source'. Raise DistutilsFileError if 'source' does not exist.

    Note that this test is not very accurate: files created in the same second
    will have the same "age".
    """
    if not os.path.exists(source):
        raise DistutilsFileError("file '%s' does not exist" %
                                 os.path.abspath(source))
    if not os.path.exists(target):
        return True

    return os.stat(source).st_mtime > os.stat(target).st_mtime 

def load_stats(self, arg):
        if not arg:  self.stats = {}
        elif isinstance(arg, basestring):
            f = open(arg, 'rb')
            self.stats = marshal.load(f)
            f.close()
            try:
                file_stats = os.stat(arg)
                arg = time.ctime(file_stats.st_mtime) + "    " + arg
            except:  # in case this is not unix
                pass
            self.files = [ arg ]
        elif hasattr(arg, 'create_stats'):
            arg.create_stats()
            self.stats = arg.stats
            arg.stats = {}
        if not self.stats:
            raise TypeError,  "Cannot create or construct a %r object from '%r''" % (
                              self.__class__, arg)
        return 

def synopsis(filename, cache={}):
    """Get the one-line summary out of a module file."""
    mtime = os.stat(filename).st_mtime
    lastupdate, result = cache.get(filename, (0, None))
    if lastupdate < mtime:
        info = inspect.getmoduleinfo(filename)
        try:
            file = open(filename)
        except IOError:
            # module can't be opened, so skip it
            return None
        if info and 'b' in info[2]: # binary modules have to be imported
            try: module = imp.load_module('__temp__', file, filename, info[1:])
            except: return None
            result = (module.__doc__ or '').splitlines()[0]
            del sys.modules['__temp__']
        else: # text modules can be directly examined
            result = source_synopsis(file)
            file.close()
        cache[filename] = (mtime, result)
    return result 

def listsubfolders(self, name):
        """Return the names of the subfolders in a given folder
        (prefixed with the given folder name)."""
        fullname = os.path.join(self.path, name)
        # Get the link count so we can avoid listing folders
        # that have no subfolders.
        nlinks = os.stat(fullname).st_nlink
        if nlinks <= 2:
            return []
        subfolders = []
        subnames = os.listdir(fullname)
        for subname in subnames:
            fullsubname = os.path.join(fullname, subname)
            if os.path.isdir(fullsubname):
                name_subname = os.path.join(name, subname)
                subfolders.append(name_subname)
                # Stop looking for subfolders when
                # we've seen them all
                nlinks = nlinks - 1
                if nlinks <= 2:
                    break
        subfolders.sort()
        return subfolders 

def copyfile(src, dst):
    """Copy data from src to dst"""
    if _samefile(src, dst):
        raise Error("`%s` and `%s` are the same file" % (src, dst))

    for fn in [src, dst]:
        try:
            st = os.stat(fn)
        except OSError:
            # File most likely does not exist
            pass
        else:
            # XXX What about other special files? (sockets, devices...)
            if stat.S_ISFIFO(st.st_mode):
                raise SpecialFileError("`%s` is a named pipe" % fn)

    with open(src, 'rb') as fsrc:
        with open(dst, 'wb') as fdst:
            copyfileobj(fsrc, fdst) 

def get_latest_data_subdir(pattern=None, take=-1):
    def get_date(f):
        return os.stat(os.path.join(BASE_DATA_DIR, f)).st_mtime

    try:
        dirs = next(os.walk(BASE_DATA_DIR))[1]
    except StopIteration:
        return None

    if pattern is not None:
        dirs = (d for d in dirs if pattern in d)

    dirs = list(sorted(dirs, key=get_date))
    if len(dirs) == 0:
        return None

    return dirs[take] 

def filemetadata(filename):
    # type: (str) -> Optional[FileMeta]
    p_filename = which(filename)
    if p_filename is None:
        return None
    filename = p_filename
    s = os.stat(filename)
    if filename != sys.executable:
        result = run_executable(filename, ['--version'])
        versionstring = result.stdout
    else:
        # filename is the Python interpreter itself
        versionstring = bytestr(sys.version)
    return FileMeta(filename, s.st_size, s.st_mtime, filesha(filename), versionstring)

# ---------------------------------------------------------------------- 

def handle(self, *args, **options):
        commit_msg_path = os.path.join(self.HOOK_PATH, 'commit-msg')

        hook_exists = os.path.exists(commit_msg_path)

        if hook_exists:
            with open(commit_msg_path, 'r') as fp:
                hook_content = fp.read()
        else:
            hook_content = '#!/usr/bin/env bash\n\n'

        if 'ZERODOWNTIME_COMMIT_MSG_HOOK' not in hook_content:
            hook_content += COMMIT_MSG_HOOK

            with open(commit_msg_path, 'w') as fp:
                fp.write(hook_content)

            st = os.stat(commit_msg_path)
            os.chmod(commit_msg_path, st.st_mode | stat.S_IEXEC) 

def _clean_upgrade(binary_ok, binary_path, path, temp_path):
    if binary_ok:
        import stat
        # save the permissions from the current binary
        old_stat = os.stat(binary_path)
        # rename the current binary in order to replace it with the latest
        os.rename(binary_path, path + "/old")
        os.rename(temp_path, binary_path)
        # set the same permissions that had the previous binary
        os.chmod(binary_path, old_stat.st_mode | stat.S_IEXEC)
        # delete the old binary
        os.remove(path + "/old")
        print("mongoaudit updated, restarting...")
        os.execl(binary_path, binary_path, *sys.argv)
    else:
        os.remove(temp_path)
        print("couldn't download the latest binary") 

def handle_ref_error(self):
        try:
            if os.stat(self.ref).st_size>0:
                with open(self.ref) as f:
                    for i in range(2):
                        line=f.next().strip()
                        if i == 0 and line[0]!='>':
                            return QtGui.QMessageBox.question(self, 'Error !', 'Please check your input reference !',
                            QtGui.QMessageBox.Ok)
                        if i == 1 and len(re.findall("[^ATGCN]", line.upper()))>0:
                            return QtGui.QMessageBox.question(self, 'Error !', 'Please check your input reference !',
                            QtGui.QMessageBox.Ok)
            else:
                return QtGui.QMessageBox.question(self, 'Warning !', 'The selected reference file is empty, please check !',
                QtGui.QMessageBox.Ok)
        except:
            return QtGui.QMessageBox.question(self, 'Error !', 'Please input a reference file !',
            QtGui.QMessageBox.Ok) 

def find_INSTALL(Makefile, flags):
    '''
    See the doc-string for find_prefix as well.
    
    Sets Makefile['INSTALL'] if needed.
    
    $(INSTALL) is normally "install", but on Solares it needs to be
    "/usr/ucb/install".
    '''
    if 'INSTALL' not in Makefile:
        trywith = [
            '/usr/ucb/install'
        ]
        for install in trywith:
            try:
                os.stat(install)
            except:
                continue
            if flags['v']:
                sys.stdout.write('Using "' + install + '" as `install`\n.')
            Makefile['INSTALL'] = install
            return False
        Makefile['INSTALL'] = 'install'
        return False 

def __hashEntry(self, prefix, entry, s):
        if stat.S_ISREG(s.st_mode):
            digest = self.__index.check(prefix, entry, s, hashFile)
        elif stat.S_ISDIR(s.st_mode):
            digest = self.__hashDir(prefix, entry)
        elif stat.S_ISLNK(s.st_mode):
            digest = self.__index.check(prefix, entry, s, DirHasher.__hashLink)
        elif stat.S_ISBLK(s.st_mode) or stat.S_ISCHR(s.st_mode):
            digest = struct.pack("<L", s.st_rdev)
        elif stat.S_ISFIFO(s.st_mode):
            digest = b''
        else:
            digest = b''
            logging.getLogger(__name__).warning("Unknown file: %s", entry)

        return digest 

def download(url, filename):
    """Download .su3 file, return True on success"""
    USER_AGENT = "Wget/1.11.4"

    url = "{}i2pseeds.su3".format(url)
    req = urllib.request.Request(url, headers={"User-Agent": USER_AGENT})

    try:
        with urllib.request.urlopen(req) as resp:
            with open(filename, 'wb') as f:
                f.write(resp.read())

        if os.stat(filename).st_size > 0:
            return True
        else:
            return False
    except URLError as e:
        return False 

def assert_file_contents_equal(a, b):
    '''
    Assert that two files have the same size and hash.
    '''
    def generate_error_message(a, b):
        '''
        This creates the error message for the assertion error
        '''
        size_a = os.stat(a).st_size
        size_b = os.stat(b).st_size
        if size_a == size_b:
            return "Files have the same size but different contents"
        else:
            return "Files have different sizes: a:%d b: %d" % (size_a, size_b)

    assert file_digest(a) == file_digest(b), generate_error_message(a, b) 

def assert_file_contents_equal(a, b):
    '''
    Assert that two files have the same size and hash.
    '''
    def generate_error_message(a, b):
        '''
        This creates the error message for the assertion error
        '''
        size_a = os.stat(a).st_size
        size_b = os.stat(b).st_size
        if size_a == size_b:
            return "Files have the same size but different contents"
        else:
            return "Files have different sizes: a:%d b: %d" % (size_a, size_b)

    assert file_digest(a) == file_digest(b), generate_error_message(a, b) 

def maybe_download_and_extract(dir_path, url_name, is_tarfile=False, is_zipfile=False):
    if not os.path.exists(dir_path):
        os.makedirs(dir_path)
    filename = url_name.split('/')[-1]
    filepath = os.path.join(dir_path, filename)
    if not os.path.exists(filepath):
        def _progress(count, block_size, total_size):
            sys.stdout.write(
                '\r>> Downloading %s %.1f%%' % (filename, float(count * block_size) / float(total_size) * 100.0))
            sys.stdout.flush()

        filepath, _ = urllib.request.urlretrieve(url_name, filepath, reporthook=_progress)
        print()
        statinfo = os.stat(filepath)
        print('Succesfully downloaded', filename, statinfo.st_size, 'bytes.')
        if is_tarfile:
            tarfile.open(filepath, 'r:gz').extractall(dir_path)
        elif is_zipfile:
            with zipfile.ZipFile(filepath) as zf:
                zip_dir = zf.namelist()[0]
                zf.extractall(dir_path) 

def cached_data_age(self, name):
        """Return age of data cached at `name` in seconds or 0 if
        cache doesn't exist

        :param name: name of datastore
        :type name: ``unicode``
        :returns: age of datastore in seconds
        :rtype: ``int``

        """

        cache_path = self.cachefile('%s.%s' % (name, self.cache_serializer))

        if not os.path.exists(cache_path):
            return 0

        return time.time() - os.stat(cache_path).st_mtime 

def cached_data_age(self, name):
        """Return age of data cached at `name` in seconds or 0 if
        cache doesn't exist

        :param name: name of datastore
        :type name: ``unicode``
        :returns: age of datastore in seconds
        :rtype: ``int``

        """

        cache_path = self.cachefile('%s.%s' % (name, self.cache_serializer))

        if not os.path.exists(cache_path):
            return 0

        return time.time() - os.stat(cache_path).st_mtime 

def _warn_unsafe_extraction_path(path):
        """
        If the default extraction path is overridden and set to an insecure
        location, such as /tmp, it opens up an opportunity for an attacker to
        replace an extracted file with an unauthorized payload. Warn the user
        if a known insecure location is used.

        See Distribute #375 for more details.
        """
        if os.name == 'nt' and not path.startswith(os.environ['windir']):
            # On Windows, permissions are generally restrictive by default
            #  and temp directories are not writable by other users, so
            #  bypass the warning.
            return
        mode = os.stat(path).st_mode
        if mode & stat.S_IWOTH or mode & stat.S_IWGRP:
            msg = ("%s is writable by group/others and vulnerable to attack "
                "when "
                "used with get_resource_filename. Consider a more secure "
                "location (set with .set_extraction_path or the "
                "PYTHON_EGG_CACHE environment variable)." % path)
            warnings.warn(msg, UserWarning) 

def seek(self, offset, whence=os.SEEK_SET):
            """Similar to 'seek' of file descriptor; works only for
            regular files.
            """
            if whence == os.SEEK_SET:
                self._overlap.Offset = offset
            elif whence == os.SEEK_CUR:
                self._overlap.Offset += offset
            else:
                assert whence == os.SEEK_END
                if isinstance(self._path, str):
                    sb = os.stat(self._path)
                    self._overlap.Offset = sb.st_size + offset
                else:
                    self._overlap.Offset = offset 

def seek(self, offset, whence=os.SEEK_SET):
            """Similar to 'seek' of file descriptor; works only for
            regular files.
            """
            if whence == os.SEEK_SET:
                self._overlap.Offset = offset
            elif whence == os.SEEK_CUR:
                self._overlap.Offset += offset
            else:
                assert whence == os.SEEK_END
                if isinstance(self._path, str):
                    sb = os.stat(self._path)
                    self._overlap.Offset = sb.st_size + offset
                else:
                    self._overlap.Offset = offset 

def is_block_device(path):
    '''
    Confirm device at path is a valid block device node.

    :returns: boolean: True if path is a block device, False if not.
    '''
    if not os.path.exists(path):
        return False
    return S_ISBLK(os.stat(path).st_mode) 

def maybe_download(filename, work_directory):
  """Download the data from Yann's website, unless it's already here."""
  if not os.path.exists(work_directory):
    os.mkdir(work_directory)
  filepath = os.path.join(work_directory, filename)
  if not os.path.exists(filepath):
    filepath, _ = urllib.request.urlretrieve(SOURCE_URL + filename, filepath)
    statinfo = os.stat(filepath)
    print('Succesfully downloaded', filename, statinfo.st_size, 'bytes.')
  return filepath 

def maybe_download(filename, work_directory):
  """Download the data from Yann's website, unless it's already here."""
  if not os.path.exists(work_directory):
    os.mkdir(work_directory)
  filepath = os.path.join(work_directory, filename)
  if not os.path.exists(filepath):
    filepath, _ = urllib.request.urlretrieve(SOURCE_URL + filename, filepath)
    statinfo = os.stat(filepath)
    print('Succesfully downloaded', filename, statinfo.st_size, 'bytes.')
  return filepath 

def cached_data_age(self, name):
        """Return age in seconds of cache `name` or 0 if cache doesn't exist.

        :param name: name of datastore
        :type name: ``unicode``
        :returns: age of datastore in seconds
        :rtype: ``int``

        """
        cache_path = self.cachefile('%s.%s' % (name, self.cache_serializer))

        if not os.path.exists(cache_path):
            return 0

        return time.time() - os.stat(cache_path).st_mtime