def from_stream(cls, stream, offset=None):
"""Creates a :class:`SHITEMID` from a stream.
:type stream: :class:`lf.dec.IStream`
:param stream: A stream that contains the structure.
:type offset: ``int``
:param offset: The start of the structure in :attr:`stream`
:rtype: :class:`SHITEMID`
:returns: The corresponding :class:`SHITEMID` object.
"""
if offset is not None:
stream.seek(offset, SEEK_SET)
# end if
data = stream.read(2)
if len(data) < 2:
return cls((len(data), 0, None))
# end if
size = uint16_le.from_buffer_copy(data).value
if size <= 2:
return cls((2, size, None))
# end if
data_size = size - 2
data = stream.read(data_size)
return cls((len(data) + 2, size, data))
def from_stream(cls, stream, offset=None):
"""Creates a :class:`SHITEMID` from a stream.
:type stream: :class:`lf.dec.IStream`
:param stream: A stream that contains the structure.
:type offset: ``int``
:param offset: The start of the structure in :attr:`stream`
:rtype: :class:`SHITEMID`
:returns: The corresponding :class:`SHITEMID` object.
"""
if offset is not None:
stream.seek(offset, SEEK_SET)
# end if
data = stream.read(2)
if len(data) < 2:
return cls((len(data), 0, None))
# end if
size = uint16_le.from_buffer_copy(data).value
if size <= 2:
return cls((2, size, None))
# end if
data_size = size - 2
data = stream.read(data_size)
return cls((len(data) + 2, size, data))
def uint16_le(self, offset=None):
""" Reads an unsigned 16-bit integer (little endian).
:type offset: :class:`int` or :keyword:`None`
:param offset: The start of the integer.
:except ValueError: if :attr:`stream` (starting at :attr:`offset` is
too small.)
:rtype: :class:`int`
:returns: The corresponding value.
"""
if offset is not None:
self.stream.seek(offset, SEEK_SET)
# end if
return uint16_le.from_buffer_copy(self.stream.read(2)).value
