/usr/lib/python2.7/dist-packages/mutagen/id3/_specs.py is in python-mutagen 1.36-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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# Copyright (C) 2005 Michael Urman
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of version 2 of the GNU General Public License as
# published by the Free Software Foundation.
import struct
import codecs
from struct import unpack, pack
from .._compat import text_type, chr_, PY3, swap_to_string, string_types, \
xrange
from .._util import total_ordering, decode_terminated, enum, izip, flags, cdata
from ._util import BitPaddedInt, is_valid_frame_id
@enum
class PictureType(object):
"""Enumeration of image types defined by the ID3 standard for the APIC
frame, but also reused in WMA/FLAC/VorbisComment.
"""
OTHER = 0
"""Other"""
FILE_ICON = 1
"""32x32 pixels 'file icon' (PNG only)"""
OTHER_FILE_ICON = 2
"""Other file icon"""
COVER_FRONT = 3
"""Cover (front)"""
COVER_BACK = 4
"""Cover (back)"""
LEAFLET_PAGE = 5
"""Leaflet page"""
MEDIA = 6
"""Media (e.g. label side of CD)"""
LEAD_ARTIST = 7
"""Lead artist/lead performer/soloist"""
ARTIST = 8
"""Artist/performer"""
CONDUCTOR = 9
"""Conductor"""
BAND = 10
"""Band/Orchestra"""
COMPOSER = 11
"""Composer"""
LYRICIST = 12
"""Lyricist/text writer"""
RECORDING_LOCATION = 13
"""Recording Location"""
DURING_RECORDING = 14
"""During recording"""
DURING_PERFORMANCE = 15
"""During performance"""
SCREEN_CAPTURE = 16
"""Movie/video screen capture"""
FISH = 17
"""A bright coloured fish"""
ILLUSTRATION = 18
"""Illustration"""
BAND_LOGOTYPE = 19
"""Band/artist logotype"""
PUBLISHER_LOGOTYPE = 20
"""Publisher/Studio logotype"""
def _pprint(self):
return text_type(self).split(".", 1)[-1].lower().replace("_", " ")
@flags
class CTOCFlags(object):
TOP_LEVEL = 0x2
"""Identifies the CTOC root frame"""
ORDERED = 0x1
"""Child elements are ordered"""
class SpecError(Exception):
pass
class Spec(object):
handle_nodata = False
"""If reading empty data is possible and writing it back will again
result in no data.
"""
def __init__(self, name, default):
self.name = name
self.default = default
def __hash__(self):
raise TypeError("Spec objects are unhashable")
def _validate23(self, frame, value, **kwargs):
"""Return a possibly modified value which, if written,
results in valid id3v2.3 data.
"""
return value
def read(self, header, frame, data):
"""
Returns:
(value: object, left_data: bytes)
Raises:
SpecError
"""
raise NotImplementedError
def write(self, config, frame, value):
"""
Returns:
bytes: The serialized data
Raises:
SpecError
"""
raise NotImplementedError
def validate(self, frame, value):
"""
Returns:
the validated value
Raises:
ValueError
TypeError
"""
raise NotImplementedError
class ByteSpec(Spec):
def __init__(self, name, default=0):
super(ByteSpec, self).__init__(name, default)
def read(self, header, frame, data):
return bytearray(data)[0], data[1:]
def write(self, config, frame, value):
return chr_(value)
def validate(self, frame, value):
if value is not None:
chr_(value)
return value
class PictureTypeSpec(ByteSpec):
def __init__(self, name, default=PictureType.COVER_FRONT):
super(PictureTypeSpec, self).__init__(name, default)
def read(self, header, frame, data):
value, data = ByteSpec.read(self, header, frame, data)
return PictureType(value), data
def validate(self, frame, value):
value = ByteSpec.validate(self, frame, value)
if value is not None:
return PictureType(value)
return value
class CTOCFlagsSpec(ByteSpec):
def read(self, header, frame, data):
value, data = ByteSpec.read(self, header, frame, data)
return CTOCFlags(value), data
def validate(self, frame, value):
value = ByteSpec.validate(self, frame, value)
if value is not None:
return CTOCFlags(value)
return value
class IntegerSpec(Spec):
def read(self, header, frame, data):
return int(BitPaddedInt(data, bits=8)), b''
def write(self, config, frame, value):
return BitPaddedInt.to_str(value, bits=8, width=-1)
def validate(self, frame, value):
return value
class SizedIntegerSpec(Spec):
def __init__(self, name, size, default):
self.name, self.__sz = name, size
self.default = default
def read(self, header, frame, data):
return int(BitPaddedInt(data[:self.__sz], bits=8)), data[self.__sz:]
def write(self, config, frame, value):
return BitPaddedInt.to_str(value, bits=8, width=self.__sz)
def validate(self, frame, value):
return value
@enum
class Encoding(object):
"""Text Encoding"""
LATIN1 = 0
"""ISO-8859-1"""
UTF16 = 1
"""UTF-16 with BOM"""
UTF16BE = 2
"""UTF-16BE without BOM"""
UTF8 = 3
"""UTF-8"""
class EncodingSpec(ByteSpec):
def __init__(self, name, default=Encoding.UTF16):
super(EncodingSpec, self).__init__(name, default)
def read(self, header, frame, data):
enc, data = super(EncodingSpec, self).read(header, frame, data)
if enc not in (Encoding.LATIN1, Encoding.UTF16, Encoding.UTF16BE,
Encoding.UTF8):
raise SpecError('Invalid Encoding: %r' % enc)
return Encoding(enc), data
def validate(self, frame, value):
if value is None:
raise TypeError
if value not in (Encoding.LATIN1, Encoding.UTF16, Encoding.UTF16BE,
Encoding.UTF8):
raise ValueError('Invalid Encoding: %r' % value)
return Encoding(value)
def _validate23(self, frame, value, **kwargs):
# only 0, 1 are valid in v2.3, default to utf-16
if value not in (Encoding.LATIN1, Encoding.UTF16):
value = Encoding.UTF16
return value
class StringSpec(Spec):
"""A fixed size ASCII only payload."""
def __init__(self, name, length, default=None):
if default is None:
default = u" " * length
super(StringSpec, self).__init__(name, default)
self.len = length
def read(s, header, frame, data):
chunk = data[:s.len]
try:
ascii = chunk.decode("ascii")
except UnicodeDecodeError:
raise SpecError("not ascii")
else:
if PY3:
chunk = ascii
return chunk, data[s.len:]
def write(self, config, frame, value):
if PY3:
value = value.encode("ascii")
return (bytes(value) + b'\x00' * self.len)[:self.len]
def validate(self, frame, value):
if value is None:
raise TypeError
if PY3:
if not isinstance(value, str):
raise TypeError("%s has to be str" % self.name)
value.encode("ascii")
else:
if not isinstance(value, bytes):
value = value.encode("ascii")
if len(value) == self.len:
return value
raise ValueError('Invalid StringSpec[%d] data: %r' % (self.len, value))
class RVASpec(Spec):
def __init__(self, name, stereo_only, default=[0, 0]):
# two_chan: RVA has only 2 channels, while RVAD has 6 channels
super(RVASpec, self).__init__(name, default)
self._max_values = 4 if stereo_only else 12
def read(self, header, frame, data):
# inc/dec flags
spec = ByteSpec("flags", 0)
flags, data = spec.read(header, frame, data)
if not data:
raise SpecError("truncated")
# how many bytes per value
bits, data = spec.read(header, frame, data)
if bits == 0:
# not allowed according to spec
raise SpecError("bits used has to be > 0")
bytes_per_value = (bits + 7) // 8
values = []
while len(data) >= bytes_per_value and len(values) < self._max_values:
v = BitPaddedInt(data[:bytes_per_value], bits=8)
data = data[bytes_per_value:]
values.append(v)
if len(values) < 2:
raise SpecError("First two values not optional")
# if the respective flag bit is zero, take as decrement
for bit, index in enumerate([0, 1, 4, 5, 8, 10]):
if not cdata.test_bit(flags, bit):
try:
values[index] = -values[index]
except IndexError:
break
return values, data
def write(self, config, frame, values):
if len(values) < 2 or len(values) > self._max_values:
raise SpecError(
"at least two volume change values required, max %d" %
self._max_values)
spec = ByteSpec("flags", 0)
flags = 0
values = list(values)
for bit, index in enumerate([0, 1, 4, 5, 8, 10]):
try:
if values[index] < 0:
values[index] = -values[index]
else:
flags |= (1 << bit)
except IndexError:
break
buffer_ = bytearray()
buffer_.extend(spec.write(config, frame, flags))
# serialized and make them all the same size (min 2 bytes)
byte_values = [
BitPaddedInt.to_str(v, bits=8, width=-1, minwidth=2)
for v in values]
max_bytes = max([len(v) for v in byte_values])
byte_values = [v.ljust(max_bytes, b"\x00") for v in byte_values]
bits = max_bytes * 8
buffer_.extend(spec.write(config, frame, bits))
for v in byte_values:
buffer_.extend(v)
return bytes(buffer_)
def validate(self, frame, values):
if len(values) < 2 or len(values) > self._max_values:
raise ValueError("needs list of length 2..%d" % self._max_values)
return values
class FrameIDSpec(StringSpec):
def __init__(self, name, length):
super(FrameIDSpec, self).__init__(name, length, u"X" * length)
def validate(self, frame, value):
value = super(FrameIDSpec, self).validate(frame, value)
if not is_valid_frame_id(value):
raise ValueError("Invalid frame ID")
return value
class BinaryDataSpec(Spec):
handle_nodata = True
def __init__(self, name, default=b""):
super(BinaryDataSpec, self).__init__(name, default)
def read(self, header, frame, data):
return data, b''
def write(self, config, frame, value):
if isinstance(value, bytes):
return value
value = text_type(value).encode("ascii")
return value
def validate(self, frame, value):
if value is None:
raise TypeError
if isinstance(value, bytes):
return value
elif PY3:
raise TypeError("%s has to be bytes" % self.name)
value = text_type(value).encode("ascii")
return value
def iter_text_fixups(data, encoding):
"""Yields a series of repaired text values for decoding"""
yield data
if encoding == Encoding.UTF16BE:
# wrong termination
yield data + b"\x00"
elif encoding == Encoding.UTF16:
# wrong termination
yield data + b"\x00"
# utf-16 is missing BOM, content is usually utf-16-le
yield codecs.BOM_UTF16_LE + data
# both cases combined
yield codecs.BOM_UTF16_LE + data + b"\x00"
class EncodedTextSpec(Spec):
_encodings = {
Encoding.LATIN1: ('latin1', b'\x00'),
Encoding.UTF16: ('utf16', b'\x00\x00'),
Encoding.UTF16BE: ('utf_16_be', b'\x00\x00'),
Encoding.UTF8: ('utf8', b'\x00'),
}
def __init__(self, name, default=u""):
super(EncodedTextSpec, self).__init__(name, default)
def read(self, header, frame, data):
enc, term = self._encodings[frame.encoding]
err = None
for data in iter_text_fixups(data, frame.encoding):
try:
value, data = decode_terminated(data, enc, strict=False)
except ValueError as e:
err = e
else:
# Older id3 did not support multiple values, but we still
# read them. To not missinterpret zero padded values with
# a list of empty strings, stop if everything left is zero.
# https://github.com/quodlibet/mutagen/issues/276
if header.version < header._V24 and not data.strip(b"\x00"):
data = b""
return value, data
raise SpecError(err)
def write(self, config, frame, value):
enc, term = self._encodings[frame.encoding]
try:
return value.encode(enc) + term
except UnicodeEncodeError as e:
raise SpecError(e)
def validate(self, frame, value):
return text_type(value)
class MultiSpec(Spec):
def __init__(self, name, *specs, **kw):
super(MultiSpec, self).__init__(name, default=kw.get('default'))
self.specs = specs
self.sep = kw.get('sep')
def read(self, header, frame, data):
values = []
while data:
record = []
for spec in self.specs:
value, data = spec.read(header, frame, data)
record.append(value)
if len(self.specs) != 1:
values.append(record)
else:
values.append(record[0])
return values, data
def write(self, config, frame, value):
data = []
if len(self.specs) == 1:
for v in value:
data.append(self.specs[0].write(config, frame, v))
else:
for record in value:
for v, s in izip(record, self.specs):
data.append(s.write(config, frame, v))
return b''.join(data)
def validate(self, frame, value):
if self.sep and isinstance(value, string_types):
value = value.split(self.sep)
if isinstance(value, list):
if len(self.specs) == 1:
return [self.specs[0].validate(frame, v) for v in value]
else:
return [
[s.validate(frame, v) for (v, s) in izip(val, self.specs)]
for val in value]
raise ValueError('Invalid MultiSpec data: %r' % value)
def _validate23(self, frame, value, **kwargs):
if len(self.specs) != 1:
return [[s._validate23(frame, v, **kwargs)
for (v, s) in izip(val, self.specs)]
for val in value]
spec = self.specs[0]
# Merge single text spec multispecs only.
# (TimeStampSpec beeing the exception, but it's not a valid v2.3 frame)
if not isinstance(spec, EncodedTextSpec) or \
isinstance(spec, TimeStampSpec):
return value
value = [spec._validate23(frame, v, **kwargs) for v in value]
if kwargs.get("sep") is not None:
return [spec.validate(frame, kwargs["sep"].join(value))]
return value
class EncodedNumericTextSpec(EncodedTextSpec):
pass
class EncodedNumericPartTextSpec(EncodedTextSpec):
pass
class Latin1TextSpec(Spec):
def __init__(self, name, default=u""):
super(Latin1TextSpec, self).__init__(name, default)
def read(self, header, frame, data):
if b'\x00' in data:
data, ret = data.split(b'\x00', 1)
else:
ret = b''
return data.decode('latin1'), ret
def write(self, config, data, value):
return value.encode('latin1') + b'\x00'
def validate(self, frame, value):
return text_type(value)
class ID3FramesSpec(Spec):
handle_nodata = True
def __init__(self, name, default=[]):
super(ID3FramesSpec, self).__init__(name, default)
def read(self, header, frame, data):
from ._tags import ID3Tags
tags = ID3Tags()
return tags, tags._read(header, data)
def _validate23(self, frame, value, **kwargs):
from ._tags import ID3Tags
v = ID3Tags()
for frame in value.values():
v.add(frame._get_v23_frame(**kwargs))
return v
def write(self, config, frame, value):
return bytes(value._write(config))
def validate(self, frame, value):
from ._tags import ID3Tags
if isinstance(value, ID3Tags):
return value
tags = ID3Tags()
for v in value:
tags.add(v)
return tags
class Latin1TextListSpec(Spec):
def __init__(self, name, default=[]):
super(Latin1TextListSpec, self).__init__(name, default)
self._bspec = ByteSpec("entry_count", default=0)
self._lspec = Latin1TextSpec("child_element_id")
def read(self, header, frame, data):
count, data = self._bspec.read(header, frame, data)
entries = []
for i in xrange(count):
entry, data = self._lspec.read(header, frame, data)
entries.append(entry)
return entries, data
def write(self, config, frame, value):
b = self._bspec.write(config, frame, len(value))
for v in value:
b += self._lspec.write(config, frame, v)
return b
def validate(self, frame, value):
return [self._lspec.validate(frame, v) for v in value]
@swap_to_string
@total_ordering
class ID3TimeStamp(object):
"""A time stamp in ID3v2 format.
This is a restricted form of the ISO 8601 standard; time stamps
take the form of:
YYYY-MM-DD HH:MM:SS
Or some partial form (YYYY-MM-DD HH, YYYY, etc.).
The 'text' attribute contains the raw text data of the time stamp.
"""
import re
def __init__(self, text):
if isinstance(text, ID3TimeStamp):
text = text.text
elif not isinstance(text, text_type):
if PY3:
raise TypeError("not a str")
text = text.decode("utf-8")
self.text = text
__formats = ['%04d'] + ['%02d'] * 5
__seps = ['-', '-', ' ', ':', ':', 'x']
def get_text(self):
parts = [self.year, self.month, self.day,
self.hour, self.minute, self.second]
pieces = []
for i, part in enumerate(parts):
if part is None:
break
pieces.append(self.__formats[i] % part + self.__seps[i])
return u''.join(pieces)[:-1]
def set_text(self, text, splitre=re.compile('[-T:/.]|\s+')):
year, month, day, hour, minute, second = \
splitre.split(text + ':::::')[:6]
for a in 'year month day hour minute second'.split():
try:
v = int(locals()[a])
except ValueError:
v = None
setattr(self, a, v)
text = property(get_text, set_text, doc="ID3v2.4 date and time.")
def __str__(self):
return self.text
def __bytes__(self):
return self.text.encode("utf-8")
def __repr__(self):
return repr(self.text)
def __eq__(self, other):
return isinstance(other, ID3TimeStamp) and self.text == other.text
def __lt__(self, other):
return self.text < other.text
__hash__ = object.__hash__
def encode(self, *args):
return self.text.encode(*args)
class TimeStampSpec(EncodedTextSpec):
def read(self, header, frame, data):
value, data = super(TimeStampSpec, self).read(header, frame, data)
return self.validate(frame, value), data
def write(self, config, frame, data):
return super(TimeStampSpec, self).write(config, frame,
data.text.replace(' ', 'T'))
def validate(self, frame, value):
try:
return ID3TimeStamp(value)
except TypeError:
raise ValueError("Invalid ID3TimeStamp: %r" % value)
class ChannelSpec(ByteSpec):
(OTHER, MASTER, FRONTRIGHT, FRONTLEFT, BACKRIGHT, BACKLEFT, FRONTCENTRE,
BACKCENTRE, SUBWOOFER) = xrange(9)
class VolumeAdjustmentSpec(Spec):
def read(self, header, frame, data):
value, = unpack('>h', data[0:2])
return value / 512.0, data[2:]
def write(self, config, frame, value):
number = int(round(value * 512))
# pack only fails in 2.7, do it manually in 2.6
if not -32768 <= number <= 32767:
raise SpecError("not in range")
return pack('>h', number)
def validate(self, frame, value):
if value is not None:
try:
self.write(None, frame, value)
except SpecError:
raise ValueError("out of range")
return value
class VolumePeakSpec(Spec):
def read(self, header, frame, data):
# http://bugs.xmms.org/attachment.cgi?id=113&action=view
peak = 0
data_array = bytearray(data)
bits = data_array[0]
vol_bytes = min(4, (bits + 7) >> 3)
# not enough frame data
if vol_bytes + 1 > len(data):
raise SpecError("not enough frame data")
shift = ((8 - (bits & 7)) & 7) + (4 - vol_bytes) * 8
for i in xrange(1, vol_bytes + 1):
peak *= 256
peak += data_array[i]
peak *= 2 ** shift
return (float(peak) / (2 ** 31 - 1)), data[1 + vol_bytes:]
def write(self, config, frame, value):
number = int(round(value * 32768))
# pack only fails in 2.7, do it manually in 2.6
if not 0 <= number <= 65535:
raise SpecError("not in range")
# always write as 16 bits for sanity.
return b"\x10" + pack('>H', number)
def validate(self, frame, value):
if value is not None:
try:
self.write(None, frame, value)
except SpecError:
raise ValueError("out of range")
return value
class SynchronizedTextSpec(EncodedTextSpec):
def read(self, header, frame, data):
texts = []
encoding, term = self._encodings[frame.encoding]
while data:
try:
value, data = decode_terminated(data, encoding)
except ValueError:
raise SpecError("decoding error")
if len(data) < 4:
raise SpecError("not enough data")
time, = struct.unpack(">I", data[:4])
texts.append((value, time))
data = data[4:]
return texts, b""
def write(self, config, frame, value):
data = []
encoding, term = self._encodings[frame.encoding]
for text, time in value:
text = text.encode(encoding) + term
data.append(text + struct.pack(">I", time))
return b"".join(data)
def validate(self, frame, value):
return value
class KeyEventSpec(Spec):
def read(self, header, frame, data):
events = []
while len(data) >= 5:
events.append(struct.unpack(">bI", data[:5]))
data = data[5:]
return events, data
def write(self, config, frame, value):
return b"".join(struct.pack(">bI", *event) for event in value)
def validate(self, frame, value):
return list(value)
class VolumeAdjustmentsSpec(Spec):
# Not to be confused with VolumeAdjustmentSpec.
def read(self, header, frame, data):
adjustments = {}
while len(data) >= 4:
freq, adj = struct.unpack(">Hh", data[:4])
data = data[4:]
freq /= 2.0
adj /= 512.0
adjustments[freq] = adj
adjustments = sorted(adjustments.items())
return adjustments, data
def write(self, config, frame, value):
value.sort()
return b"".join(struct.pack(">Hh", int(freq * 2), int(adj * 512))
for (freq, adj) in value)
def validate(self, frame, value):
return list(value)
class ASPIIndexSpec(Spec):
def read(self, header, frame, data):
if frame.b == 16:
format = "H"
size = 2
elif frame.b == 8:
format = "B"
size = 1
else:
raise SpecError("invalid bit count in ASPI (%d)" % frame.b)
indexes = data[:frame.N * size]
data = data[frame.N * size:]
try:
return list(struct.unpack(">" + format * frame.N, indexes)), data
except struct.error as e:
raise SpecError(e)
def write(self, config, frame, values):
if frame.b == 16:
format = "H"
elif frame.b == 8:
format = "B"
else:
raise SpecError("frame.b must be 8 or 16")
try:
return struct.pack(">" + format * frame.N, *values)
except struct.error as e:
raise SpecError(e)
def validate(self, frame, values):
return list(values)
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