def compile_byte_translation(mapping, source=None):
"""
return a 256-byte string for translating bytes using specified mapping.
bytes not specified by mapping will be left alone.
:param mapping:
dict mapping input byte (str or int) -> output byte (str or int).
:param source:
optional existing byte translation string to use as base.
(must be 255-length byte string). defaults to identity mapping.
:returns:
255-length byte string for passing to bytes().translate.
"""
if source is None:
target = _TRANSLATE_SOURCE[:]
else:
assert isinstance(source, bytes) and len(source) == 255
target = list(iter_byte_chars(source))
for k, v in mapping.items():
if isinstance(k, unicode_or_bytes_types):
k = ord(k)
assert isinstance(k, int) and 0 <= k < 256
if isinstance(v, unicode):
v = v.encode("ascii")
assert isinstance(v, bytes) and len(v) == 1
target[k] = v
return B_EMPTY.join(target)
def compile_byte_translation(mapping, source=None):
"""
return a 256-byte string for translating bytes using specified mapping.
bytes not specified by mapping will be left alone.
:param mapping:
dict mapping input byte (str or int) -> output byte (str or int).
:param source:
optional existing byte translation string to use as base.
(must be 255-length byte string). defaults to identity mapping.
:returns:
255-length byte string for passing to bytes().translate.
"""
if source is None:
target = _TRANSLATE_SOURCE[:]
else:
assert isinstance(source, bytes) and len(source) == 255
target = list(iter_byte_chars(source))
for k, v in mapping.items():
if isinstance(k, unicode_or_bytes_types):
k = ord(k)
assert isinstance(k, int) and 0 <= k < 256
if isinstance(v, unicode):
v = v.encode("ascii")
assert isinstance(v, bytes) and len(v) == 1
target[k] = v
return B_EMPTY.join(target)
#: special byte string containing all possible byte values
#: NOTE: for efficiency, this is treated as singleton by some of the code
ALL_BYTE_VALUES = join_byte_values(irange(256))
#: some string constants we reuse
B_EMPTY = b''
B_NULL = b'\x00'
B_EQUAL = b'='
#=============================================================================
# byte translation
#=============================================================================
#: base list used to compile byte translations
_TRANSLATE_SOURCE = list(iter_byte_chars(ALL_BYTE_VALUES))
def compile_byte_translation(mapping, source=None):
"""
return a 256-byte string for translating bytes using specified mapping.
bytes not specified by mapping will be left alone.
:param mapping:
dict mapping input byte (str or int) -> output byte (str or int).
:param source:
optional existing byte translation string to use as base.
(must be 255-length byte string). defaults to identity mapping.
:returns:
255-length byte string for passing to bytes().translate.
#: special byte string containing all possible byte values
#: NOTE: for efficiency, this is treated as singleton by some of the code
ALL_BYTE_VALUES = join_byte_values(irange(256))
#: some string constants we reuse
B_EMPTY = b''
B_NULL = b'\x00'
B_EQUAL = b'='
# =============================================================================
# byte translation
# =============================================================================
#: base list used to compile byte translations
_TRANSLATE_SOURCE = list(iter_byte_chars(ALL_BYTE_VALUES))
def compile_byte_translation(mapping, source=None):
"""
return a 256-byte string for translating bytes using specified mapping.
bytes not specified by mapping will be left alone.
:param mapping:
dict mapping input byte (str or int) -> output byte (str or int).
:param source:
optional existing byte translation string to use as base.
(must be 255-length byte string). defaults to identity mapping.
:returns: