cpython/Lib/encodings/utf_16.py

62 lines
1.8 KiB
Python

""" Python 'utf-16' Codec
Written by Marc-Andre Lemburg (mal@lemburg.com).
(c) Copyright CNRI, All Rights Reserved. NO WARRANTY.
"""
import codecs, sys
### Codec APIs
class Codec(codecs.Codec):
# Note: Binding these as C functions will result in the class not
# converting them to methods. This is intended.
encode = codecs.utf_16_encode
decode = codecs.utf_16_decode
class StreamWriter(Codec,codecs.StreamWriter):
def __init__(self, stream, errors='strict'):
self.bom_written = 0
codecs.StreamWriter.__init__(self, stream, errors)
def write(self, data):
result = codecs.StreamWriter.write(self, data)
if not self.bom_written:
self.bom_written = 1
if sys.byteorder == 'little':
self.encode = codecs.utf_16_le_encode
else:
self.encode = codecs.utf_16_be_encode
return result
class StreamReader(Codec,codecs.StreamReader):
def __init__(self, stream, errors='strict'):
self.bom_read = 0
codecs.StreamReader.__init__(self, stream, errors)
def read(self, size=-1):
if not self.bom_read:
signature = self.stream.read(2)
if signature == codecs.BOM_BE:
self.decode = codecs.utf_16_be_decode
elif signature == codecs.BOM_LE:
self.decode = codecs.utf_16_le_decode
else:
raise UnicodeError,"UTF-16 stream does not start with BOM"
if size > 2:
size -= 2
elif size >= 0:
size = 0
self.bom_read = 1
return codecs.StreamReader.read(self, size)
### encodings module API
def getregentry():
return (Codec.encode,Codec.decode,StreamReader,StreamWriter)