mirror of
https://github.com/SickGear/SickGear.git
synced 2024-12-21 10:13:39 +00:00
918 lines
32 KiB
Python
918 lines
32 KiB
Python
from __future__ import absolute_import, division, unicode_literals
|
|
|
|
from six import text_type
|
|
from six.moves import http_client, urllib
|
|
|
|
import codecs
|
|
import re
|
|
from io import BytesIO, StringIO
|
|
|
|
import webencodings
|
|
|
|
from .constants import EOF, spaceCharacters, asciiLetters, asciiUppercase
|
|
from .constants import _ReparseException
|
|
from . import _utils
|
|
|
|
# Non-unicode versions of constants for use in the pre-parser
|
|
spaceCharactersBytes = frozenset([item.encode("ascii") for item in spaceCharacters])
|
|
asciiLettersBytes = frozenset([item.encode("ascii") for item in asciiLetters])
|
|
asciiUppercaseBytes = frozenset([item.encode("ascii") for item in asciiUppercase])
|
|
spacesAngleBrackets = spaceCharactersBytes | frozenset([b">", b"<"])
|
|
|
|
|
|
invalid_unicode_no_surrogate = "[\u0001-\u0008\u000B\u000E-\u001F\u007F-\u009F\uFDD0-\uFDEF\uFFFE\uFFFF\U0001FFFE\U0001FFFF\U0002FFFE\U0002FFFF\U0003FFFE\U0003FFFF\U0004FFFE\U0004FFFF\U0005FFFE\U0005FFFF\U0006FFFE\U0006FFFF\U0007FFFE\U0007FFFF\U0008FFFE\U0008FFFF\U0009FFFE\U0009FFFF\U000AFFFE\U000AFFFF\U000BFFFE\U000BFFFF\U000CFFFE\U000CFFFF\U000DFFFE\U000DFFFF\U000EFFFE\U000EFFFF\U000FFFFE\U000FFFFF\U0010FFFE\U0010FFFF]" # noqa
|
|
|
|
if _utils.supports_lone_surrogates:
|
|
# Use one extra step of indirection and create surrogates with
|
|
# eval. Not using this indirection would introduce an illegal
|
|
# unicode literal on platforms not supporting such lone
|
|
# surrogates.
|
|
assert invalid_unicode_no_surrogate[-1] == "]" and invalid_unicode_no_surrogate.count("]") == 1
|
|
invalid_unicode_re = re.compile(invalid_unicode_no_surrogate[:-1] +
|
|
eval('"\\uD800-\\uDFFF"') + # pylint:disable=eval-used
|
|
"]")
|
|
else:
|
|
invalid_unicode_re = re.compile(invalid_unicode_no_surrogate)
|
|
|
|
non_bmp_invalid_codepoints = {0x1FFFE, 0x1FFFF, 0x2FFFE, 0x2FFFF, 0x3FFFE,
|
|
0x3FFFF, 0x4FFFE, 0x4FFFF, 0x5FFFE, 0x5FFFF,
|
|
0x6FFFE, 0x6FFFF, 0x7FFFE, 0x7FFFF, 0x8FFFE,
|
|
0x8FFFF, 0x9FFFE, 0x9FFFF, 0xAFFFE, 0xAFFFF,
|
|
0xBFFFE, 0xBFFFF, 0xCFFFE, 0xCFFFF, 0xDFFFE,
|
|
0xDFFFF, 0xEFFFE, 0xEFFFF, 0xFFFFE, 0xFFFFF,
|
|
0x10FFFE, 0x10FFFF}
|
|
|
|
ascii_punctuation_re = re.compile("[\u0009-\u000D\u0020-\u002F\u003A-\u0040\u005C\u005B-\u0060\u007B-\u007E]")
|
|
|
|
# Cache for charsUntil()
|
|
charsUntilRegEx = {}
|
|
|
|
|
|
class BufferedStream(object):
|
|
"""Buffering for streams that do not have buffering of their own
|
|
|
|
The buffer is implemented as a list of chunks on the assumption that
|
|
joining many strings will be slow since it is O(n**2)
|
|
"""
|
|
|
|
def __init__(self, stream):
|
|
self.stream = stream
|
|
self.buffer = []
|
|
self.position = [-1, 0] # chunk number, offset
|
|
|
|
def tell(self):
|
|
pos = 0
|
|
for chunk in self.buffer[:self.position[0]]:
|
|
pos += len(chunk)
|
|
pos += self.position[1]
|
|
return pos
|
|
|
|
def seek(self, pos):
|
|
assert pos <= self._bufferedBytes()
|
|
offset = pos
|
|
i = 0
|
|
while len(self.buffer[i]) < offset:
|
|
offset -= len(self.buffer[i])
|
|
i += 1
|
|
self.position = [i, offset]
|
|
|
|
def read(self, bytes):
|
|
if not self.buffer:
|
|
return self._readStream(bytes)
|
|
elif (self.position[0] == len(self.buffer) and
|
|
self.position[1] == len(self.buffer[-1])):
|
|
return self._readStream(bytes)
|
|
else:
|
|
return self._readFromBuffer(bytes)
|
|
|
|
def _bufferedBytes(self):
|
|
return sum([len(item) for item in self.buffer])
|
|
|
|
def _readStream(self, bytes):
|
|
data = self.stream.read(bytes)
|
|
self.buffer.append(data)
|
|
self.position[0] += 1
|
|
self.position[1] = len(data)
|
|
return data
|
|
|
|
def _readFromBuffer(self, bytes):
|
|
remainingBytes = bytes
|
|
rv = []
|
|
bufferIndex = self.position[0]
|
|
bufferOffset = self.position[1]
|
|
while bufferIndex < len(self.buffer) and remainingBytes != 0:
|
|
assert remainingBytes > 0
|
|
bufferedData = self.buffer[bufferIndex]
|
|
|
|
if remainingBytes <= len(bufferedData) - bufferOffset:
|
|
bytesToRead = remainingBytes
|
|
self.position = [bufferIndex, bufferOffset + bytesToRead]
|
|
else:
|
|
bytesToRead = len(bufferedData) - bufferOffset
|
|
self.position = [bufferIndex, len(bufferedData)]
|
|
bufferIndex += 1
|
|
rv.append(bufferedData[bufferOffset:bufferOffset + bytesToRead])
|
|
remainingBytes -= bytesToRead
|
|
|
|
bufferOffset = 0
|
|
|
|
if remainingBytes:
|
|
rv.append(self._readStream(remainingBytes))
|
|
|
|
return b"".join(rv)
|
|
|
|
|
|
def HTMLInputStream(source, **kwargs):
|
|
# Work around Python bug #20007: read(0) closes the connection.
|
|
# http://bugs.python.org/issue20007
|
|
if (isinstance(source, http_client.HTTPResponse) or
|
|
# Also check for addinfourl wrapping HTTPResponse
|
|
(isinstance(source, urllib.response.addbase) and
|
|
isinstance(source.fp, http_client.HTTPResponse))):
|
|
isUnicode = False
|
|
elif hasattr(source, "read"):
|
|
isUnicode = isinstance(source.read(0), text_type)
|
|
else:
|
|
isUnicode = isinstance(source, text_type)
|
|
|
|
if isUnicode:
|
|
encodings = [x for x in kwargs if x.endswith("_encoding")]
|
|
if encodings:
|
|
raise TypeError("Cannot set an encoding with a unicode input, set %r" % encodings)
|
|
|
|
return HTMLUnicodeInputStream(source, **kwargs)
|
|
else:
|
|
return HTMLBinaryInputStream(source, **kwargs)
|
|
|
|
|
|
class HTMLUnicodeInputStream(object):
|
|
"""Provides a unicode stream of characters to the HTMLTokenizer.
|
|
|
|
This class takes care of character encoding and removing or replacing
|
|
incorrect byte-sequences and also provides column and line tracking.
|
|
|
|
"""
|
|
|
|
_defaultChunkSize = 10240
|
|
|
|
def __init__(self, source):
|
|
"""Initialises the HTMLInputStream.
|
|
|
|
HTMLInputStream(source, [encoding]) -> Normalized stream from source
|
|
for use by html5lib.
|
|
|
|
source can be either a file-object, local filename or a string.
|
|
|
|
The optional encoding parameter must be a string that indicates
|
|
the encoding. If specified, that encoding will be used,
|
|
regardless of any BOM or later declaration (such as in a meta
|
|
element)
|
|
|
|
"""
|
|
|
|
if not _utils.supports_lone_surrogates:
|
|
# Such platforms will have already checked for such
|
|
# surrogate errors, so no need to do this checking.
|
|
self.reportCharacterErrors = None
|
|
elif len("\U0010FFFF") == 1:
|
|
self.reportCharacterErrors = self.characterErrorsUCS4
|
|
else:
|
|
self.reportCharacterErrors = self.characterErrorsUCS2
|
|
|
|
# List of where new lines occur
|
|
self.newLines = [0]
|
|
|
|
self.charEncoding = (lookupEncoding("utf-8"), "certain")
|
|
self.dataStream = self.openStream(source)
|
|
|
|
self.reset()
|
|
|
|
def reset(self):
|
|
self.chunk = ""
|
|
self.chunkSize = 0
|
|
self.chunkOffset = 0
|
|
self.errors = []
|
|
|
|
# number of (complete) lines in previous chunks
|
|
self.prevNumLines = 0
|
|
# number of columns in the last line of the previous chunk
|
|
self.prevNumCols = 0
|
|
|
|
# Deal with CR LF and surrogates split over chunk boundaries
|
|
self._bufferedCharacter = None
|
|
|
|
def openStream(self, source):
|
|
"""Produces a file object from source.
|
|
|
|
source can be either a file object, local filename or a string.
|
|
|
|
"""
|
|
# Already a file object
|
|
if hasattr(source, 'read'):
|
|
stream = source
|
|
else:
|
|
stream = StringIO(source)
|
|
|
|
return stream
|
|
|
|
def _position(self, offset):
|
|
chunk = self.chunk
|
|
nLines = chunk.count('\n', 0, offset)
|
|
positionLine = self.prevNumLines + nLines
|
|
lastLinePos = chunk.rfind('\n', 0, offset)
|
|
if lastLinePos == -1:
|
|
positionColumn = self.prevNumCols + offset
|
|
else:
|
|
positionColumn = offset - (lastLinePos + 1)
|
|
return (positionLine, positionColumn)
|
|
|
|
def position(self):
|
|
"""Returns (line, col) of the current position in the stream."""
|
|
line, col = self._position(self.chunkOffset)
|
|
return (line + 1, col)
|
|
|
|
def char(self):
|
|
""" Read one character from the stream or queue if available. Return
|
|
EOF when EOF is reached.
|
|
"""
|
|
# Read a new chunk from the input stream if necessary
|
|
if self.chunkOffset >= self.chunkSize:
|
|
if not self.readChunk():
|
|
return EOF
|
|
|
|
chunkOffset = self.chunkOffset
|
|
char = self.chunk[chunkOffset]
|
|
self.chunkOffset = chunkOffset + 1
|
|
|
|
return char
|
|
|
|
def readChunk(self, chunkSize=None):
|
|
if chunkSize is None:
|
|
chunkSize = self._defaultChunkSize
|
|
|
|
self.prevNumLines, self.prevNumCols = self._position(self.chunkSize)
|
|
|
|
self.chunk = ""
|
|
self.chunkSize = 0
|
|
self.chunkOffset = 0
|
|
|
|
data = self.dataStream.read(chunkSize)
|
|
|
|
# Deal with CR LF and surrogates broken across chunks
|
|
if self._bufferedCharacter:
|
|
data = self._bufferedCharacter + data
|
|
self._bufferedCharacter = None
|
|
elif not data:
|
|
# We have no more data, bye-bye stream
|
|
return False
|
|
|
|
if len(data) > 1:
|
|
lastv = ord(data[-1])
|
|
if lastv == 0x0D or 0xD800 <= lastv <= 0xDBFF:
|
|
self._bufferedCharacter = data[-1]
|
|
data = data[:-1]
|
|
|
|
if self.reportCharacterErrors:
|
|
self.reportCharacterErrors(data)
|
|
|
|
# Replace invalid characters
|
|
data = data.replace("\r\n", "\n")
|
|
data = data.replace("\r", "\n")
|
|
|
|
self.chunk = data
|
|
self.chunkSize = len(data)
|
|
|
|
return True
|
|
|
|
def characterErrorsUCS4(self, data):
|
|
for _ in range(len(invalid_unicode_re.findall(data))):
|
|
self.errors.append("invalid-codepoint")
|
|
|
|
def characterErrorsUCS2(self, data):
|
|
# Someone picked the wrong compile option
|
|
# You lose
|
|
skip = False
|
|
for match in invalid_unicode_re.finditer(data):
|
|
if skip:
|
|
continue
|
|
codepoint = ord(match.group())
|
|
pos = match.start()
|
|
# Pretty sure there should be endianness issues here
|
|
if _utils.isSurrogatePair(data[pos:pos + 2]):
|
|
# We have a surrogate pair!
|
|
char_val = _utils.surrogatePairToCodepoint(data[pos:pos + 2])
|
|
if char_val in non_bmp_invalid_codepoints:
|
|
self.errors.append("invalid-codepoint")
|
|
skip = True
|
|
elif (codepoint >= 0xD800 and codepoint <= 0xDFFF and
|
|
pos == len(data) - 1):
|
|
self.errors.append("invalid-codepoint")
|
|
else:
|
|
skip = False
|
|
self.errors.append("invalid-codepoint")
|
|
|
|
def charsUntil(self, characters, opposite=False):
|
|
""" Returns a string of characters from the stream up to but not
|
|
including any character in 'characters' or EOF. 'characters' must be
|
|
a container that supports the 'in' method and iteration over its
|
|
characters.
|
|
"""
|
|
|
|
# Use a cache of regexps to find the required characters
|
|
try:
|
|
chars = charsUntilRegEx[(characters, opposite)]
|
|
except KeyError:
|
|
if __debug__:
|
|
for c in characters:
|
|
assert(ord(c) < 128)
|
|
regex = "".join(["\\x%02x" % ord(c) for c in characters])
|
|
if not opposite:
|
|
regex = "^%s" % regex
|
|
chars = charsUntilRegEx[(characters, opposite)] = re.compile("[%s]+" % regex)
|
|
|
|
rv = []
|
|
|
|
while True:
|
|
# Find the longest matching prefix
|
|
m = chars.match(self.chunk, self.chunkOffset)
|
|
if m is None:
|
|
# If nothing matched, and it wasn't because we ran out of chunk,
|
|
# then stop
|
|
if self.chunkOffset != self.chunkSize:
|
|
break
|
|
else:
|
|
end = m.end()
|
|
# If not the whole chunk matched, return everything
|
|
# up to the part that didn't match
|
|
if end != self.chunkSize:
|
|
rv.append(self.chunk[self.chunkOffset:end])
|
|
self.chunkOffset = end
|
|
break
|
|
# If the whole remainder of the chunk matched,
|
|
# use it all and read the next chunk
|
|
rv.append(self.chunk[self.chunkOffset:])
|
|
if not self.readChunk():
|
|
# Reached EOF
|
|
break
|
|
|
|
r = "".join(rv)
|
|
return r
|
|
|
|
def unget(self, char):
|
|
# Only one character is allowed to be ungotten at once - it must
|
|
# be consumed again before any further call to unget
|
|
if char is not EOF:
|
|
if self.chunkOffset == 0:
|
|
# unget is called quite rarely, so it's a good idea to do
|
|
# more work here if it saves a bit of work in the frequently
|
|
# called char and charsUntil.
|
|
# So, just prepend the ungotten character onto the current
|
|
# chunk:
|
|
self.chunk = char + self.chunk
|
|
self.chunkSize += 1
|
|
else:
|
|
self.chunkOffset -= 1
|
|
assert self.chunk[self.chunkOffset] == char
|
|
|
|
|
|
class HTMLBinaryInputStream(HTMLUnicodeInputStream):
|
|
"""Provides a unicode stream of characters to the HTMLTokenizer.
|
|
|
|
This class takes care of character encoding and removing or replacing
|
|
incorrect byte-sequences and also provides column and line tracking.
|
|
|
|
"""
|
|
|
|
def __init__(self, source, override_encoding=None, transport_encoding=None,
|
|
same_origin_parent_encoding=None, likely_encoding=None,
|
|
default_encoding="windows-1252", useChardet=True):
|
|
"""Initialises the HTMLInputStream.
|
|
|
|
HTMLInputStream(source, [encoding]) -> Normalized stream from source
|
|
for use by html5lib.
|
|
|
|
source can be either a file-object, local filename or a string.
|
|
|
|
The optional encoding parameter must be a string that indicates
|
|
the encoding. If specified, that encoding will be used,
|
|
regardless of any BOM or later declaration (such as in a meta
|
|
element)
|
|
|
|
"""
|
|
# Raw Stream - for unicode objects this will encode to utf-8 and set
|
|
# self.charEncoding as appropriate
|
|
self.rawStream = self.openStream(source)
|
|
|
|
HTMLUnicodeInputStream.__init__(self, self.rawStream)
|
|
|
|
# Encoding Information
|
|
# Number of bytes to use when looking for a meta element with
|
|
# encoding information
|
|
self.numBytesMeta = 1024
|
|
# Number of bytes to use when using detecting encoding using chardet
|
|
self.numBytesChardet = 100
|
|
# Things from args
|
|
self.override_encoding = override_encoding
|
|
self.transport_encoding = transport_encoding
|
|
self.same_origin_parent_encoding = same_origin_parent_encoding
|
|
self.likely_encoding = likely_encoding
|
|
self.default_encoding = default_encoding
|
|
|
|
# Determine encoding
|
|
self.charEncoding = self.determineEncoding(useChardet)
|
|
assert self.charEncoding[0] is not None
|
|
|
|
# Call superclass
|
|
self.reset()
|
|
|
|
def reset(self):
|
|
self.dataStream = self.charEncoding[0].codec_info.streamreader(self.rawStream, 'replace')
|
|
HTMLUnicodeInputStream.reset(self)
|
|
|
|
def openStream(self, source):
|
|
"""Produces a file object from source.
|
|
|
|
source can be either a file object, local filename or a string.
|
|
|
|
"""
|
|
# Already a file object
|
|
if hasattr(source, 'read'):
|
|
stream = source
|
|
else:
|
|
stream = BytesIO(source)
|
|
|
|
try:
|
|
stream.seek(stream.tell())
|
|
except Exception:
|
|
stream = BufferedStream(stream)
|
|
|
|
return stream
|
|
|
|
def determineEncoding(self, chardet=True):
|
|
# BOMs take precedence over everything
|
|
# This will also read past the BOM if present
|
|
charEncoding = self.detectBOM(), "certain"
|
|
if charEncoding[0] is not None:
|
|
return charEncoding
|
|
|
|
# If we've been overridden, we've been overridden
|
|
charEncoding = lookupEncoding(self.override_encoding), "certain"
|
|
if charEncoding[0] is not None:
|
|
return charEncoding
|
|
|
|
# Now check the transport layer
|
|
charEncoding = lookupEncoding(self.transport_encoding), "certain"
|
|
if charEncoding[0] is not None:
|
|
return charEncoding
|
|
|
|
# Look for meta elements with encoding information
|
|
charEncoding = self.detectEncodingMeta(), "tentative"
|
|
if charEncoding[0] is not None:
|
|
return charEncoding
|
|
|
|
# Parent document encoding
|
|
charEncoding = lookupEncoding(self.same_origin_parent_encoding), "tentative"
|
|
if charEncoding[0] is not None and not charEncoding[0].name.startswith("utf-16"):
|
|
return charEncoding
|
|
|
|
# "likely" encoding
|
|
charEncoding = lookupEncoding(self.likely_encoding), "tentative"
|
|
if charEncoding[0] is not None:
|
|
return charEncoding
|
|
|
|
# Guess with chardet, if available
|
|
if chardet:
|
|
try:
|
|
from chardet.universaldetector import UniversalDetector
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
buffers = []
|
|
detector = UniversalDetector()
|
|
while not detector.done:
|
|
buffer = self.rawStream.read(self.numBytesChardet)
|
|
assert isinstance(buffer, bytes)
|
|
if not buffer:
|
|
break
|
|
buffers.append(buffer)
|
|
detector.feed(buffer)
|
|
detector.close()
|
|
encoding = lookupEncoding(detector.result['encoding'])
|
|
self.rawStream.seek(0)
|
|
if encoding is not None:
|
|
return encoding, "tentative"
|
|
|
|
# Try the default encoding
|
|
charEncoding = lookupEncoding(self.default_encoding), "tentative"
|
|
if charEncoding[0] is not None:
|
|
return charEncoding
|
|
|
|
# Fallback to html5lib's default if even that hasn't worked
|
|
return lookupEncoding("windows-1252"), "tentative"
|
|
|
|
def changeEncoding(self, newEncoding):
|
|
assert self.charEncoding[1] != "certain"
|
|
newEncoding = lookupEncoding(newEncoding)
|
|
if newEncoding is None:
|
|
return
|
|
if newEncoding.name in ("utf-16be", "utf-16le"):
|
|
newEncoding = lookupEncoding("utf-8")
|
|
assert newEncoding is not None
|
|
elif newEncoding == self.charEncoding[0]:
|
|
self.charEncoding = (self.charEncoding[0], "certain")
|
|
else:
|
|
self.rawStream.seek(0)
|
|
self.charEncoding = (newEncoding, "certain")
|
|
self.reset()
|
|
raise _ReparseException("Encoding changed from %s to %s" % (self.charEncoding[0], newEncoding))
|
|
|
|
def detectBOM(self):
|
|
"""Attempts to detect at BOM at the start of the stream. If
|
|
an encoding can be determined from the BOM return the name of the
|
|
encoding otherwise return None"""
|
|
bomDict = {
|
|
codecs.BOM_UTF8: 'utf-8',
|
|
codecs.BOM_UTF16_LE: 'utf-16le', codecs.BOM_UTF16_BE: 'utf-16be',
|
|
codecs.BOM_UTF32_LE: 'utf-32le', codecs.BOM_UTF32_BE: 'utf-32be'
|
|
}
|
|
|
|
# Go to beginning of file and read in 4 bytes
|
|
string = self.rawStream.read(4)
|
|
assert isinstance(string, bytes)
|
|
|
|
# Try detecting the BOM using bytes from the string
|
|
encoding = bomDict.get(string[:3]) # UTF-8
|
|
seek = 3
|
|
if not encoding:
|
|
# Need to detect UTF-32 before UTF-16
|
|
encoding = bomDict.get(string) # UTF-32
|
|
seek = 4
|
|
if not encoding:
|
|
encoding = bomDict.get(string[:2]) # UTF-16
|
|
seek = 2
|
|
|
|
# Set the read position past the BOM if one was found, otherwise
|
|
# set it to the start of the stream
|
|
if encoding:
|
|
self.rawStream.seek(seek)
|
|
return lookupEncoding(encoding)
|
|
else:
|
|
self.rawStream.seek(0)
|
|
return None
|
|
|
|
def detectEncodingMeta(self):
|
|
"""Report the encoding declared by the meta element
|
|
"""
|
|
buffer = self.rawStream.read(self.numBytesMeta)
|
|
assert isinstance(buffer, bytes)
|
|
parser = EncodingParser(buffer)
|
|
self.rawStream.seek(0)
|
|
encoding = parser.getEncoding()
|
|
|
|
if encoding is not None and encoding.name in ("utf-16be", "utf-16le"):
|
|
encoding = lookupEncoding("utf-8")
|
|
|
|
return encoding
|
|
|
|
|
|
class EncodingBytes(bytes):
|
|
"""String-like object with an associated position and various extra methods
|
|
If the position is ever greater than the string length then an exception is
|
|
raised"""
|
|
def __new__(self, value):
|
|
assert isinstance(value, bytes)
|
|
return bytes.__new__(self, value.lower())
|
|
|
|
def __init__(self, value):
|
|
# pylint:disable=unused-argument
|
|
self._position = -1
|
|
|
|
def __iter__(self):
|
|
return self
|
|
|
|
def __next__(self):
|
|
p = self._position = self._position + 1
|
|
if p >= len(self):
|
|
raise StopIteration
|
|
elif p < 0:
|
|
raise TypeError
|
|
return self[p:p + 1]
|
|
|
|
def next(self):
|
|
# Py2 compat
|
|
return self.__next__()
|
|
|
|
def previous(self):
|
|
p = self._position
|
|
if p >= len(self):
|
|
raise StopIteration
|
|
elif p < 0:
|
|
raise TypeError
|
|
self._position = p = p - 1
|
|
return self[p:p + 1]
|
|
|
|
def setPosition(self, position):
|
|
if self._position >= len(self):
|
|
raise StopIteration
|
|
self._position = position
|
|
|
|
def getPosition(self):
|
|
if self._position >= len(self):
|
|
raise StopIteration
|
|
if self._position >= 0:
|
|
return self._position
|
|
else:
|
|
return None
|
|
|
|
position = property(getPosition, setPosition)
|
|
|
|
def getCurrentByte(self):
|
|
return self[self.position:self.position + 1]
|
|
|
|
currentByte = property(getCurrentByte)
|
|
|
|
def skip(self, chars=spaceCharactersBytes):
|
|
"""Skip past a list of characters"""
|
|
p = self.position # use property for the error-checking
|
|
while p < len(self):
|
|
c = self[p:p + 1]
|
|
if c not in chars:
|
|
self._position = p
|
|
return c
|
|
p += 1
|
|
self._position = p
|
|
return None
|
|
|
|
def skipUntil(self, chars):
|
|
p = self.position
|
|
while p < len(self):
|
|
c = self[p:p + 1]
|
|
if c in chars:
|
|
self._position = p
|
|
return c
|
|
p += 1
|
|
self._position = p
|
|
return None
|
|
|
|
def matchBytes(self, bytes):
|
|
"""Look for a sequence of bytes at the start of a string. If the bytes
|
|
are found return True and advance the position to the byte after the
|
|
match. Otherwise return False and leave the position alone"""
|
|
rv = self.startswith(bytes, self.position)
|
|
if rv:
|
|
self.position += len(bytes)
|
|
return rv
|
|
|
|
def jumpTo(self, bytes):
|
|
"""Look for the next sequence of bytes matching a given sequence. If
|
|
a match is found advance the position to the last byte of the match"""
|
|
try:
|
|
self._position = self.index(bytes, self.position) + len(bytes) - 1
|
|
except ValueError:
|
|
raise StopIteration
|
|
return True
|
|
|
|
|
|
class EncodingParser(object):
|
|
"""Mini parser for detecting character encoding from meta elements"""
|
|
|
|
def __init__(self, data):
|
|
"""string - the data to work on for encoding detection"""
|
|
self.data = EncodingBytes(data)
|
|
self.encoding = None
|
|
|
|
def getEncoding(self):
|
|
if b"<meta" not in self.data:
|
|
return None
|
|
|
|
methodDispatch = (
|
|
(b"<!--", self.handleComment),
|
|
(b"<meta", self.handleMeta),
|
|
(b"</", self.handlePossibleEndTag),
|
|
(b"<!", self.handleOther),
|
|
(b"<?", self.handleOther),
|
|
(b"<", self.handlePossibleStartTag))
|
|
for _ in self.data:
|
|
keepParsing = True
|
|
try:
|
|
self.data.jumpTo(b"<")
|
|
except StopIteration:
|
|
break
|
|
for key, method in methodDispatch:
|
|
if self.data.matchBytes(key):
|
|
try:
|
|
keepParsing = method()
|
|
break
|
|
except StopIteration:
|
|
keepParsing = False
|
|
break
|
|
if not keepParsing:
|
|
break
|
|
|
|
return self.encoding
|
|
|
|
def handleComment(self):
|
|
"""Skip over comments"""
|
|
return self.data.jumpTo(b"-->")
|
|
|
|
def handleMeta(self):
|
|
if self.data.currentByte not in spaceCharactersBytes:
|
|
# if we have <meta not followed by a space so just keep going
|
|
return True
|
|
# We have a valid meta element we want to search for attributes
|
|
hasPragma = False
|
|
pendingEncoding = None
|
|
while True:
|
|
# Try to find the next attribute after the current position
|
|
attr = self.getAttribute()
|
|
if attr is None:
|
|
return True
|
|
else:
|
|
if attr[0] == b"http-equiv":
|
|
hasPragma = attr[1] == b"content-type"
|
|
if hasPragma and pendingEncoding is not None:
|
|
self.encoding = pendingEncoding
|
|
return False
|
|
elif attr[0] == b"charset":
|
|
tentativeEncoding = attr[1]
|
|
codec = lookupEncoding(tentativeEncoding)
|
|
if codec is not None:
|
|
self.encoding = codec
|
|
return False
|
|
elif attr[0] == b"content":
|
|
contentParser = ContentAttrParser(EncodingBytes(attr[1]))
|
|
tentativeEncoding = contentParser.parse()
|
|
if tentativeEncoding is not None:
|
|
codec = lookupEncoding(tentativeEncoding)
|
|
if codec is not None:
|
|
if hasPragma:
|
|
self.encoding = codec
|
|
return False
|
|
else:
|
|
pendingEncoding = codec
|
|
|
|
def handlePossibleStartTag(self):
|
|
return self.handlePossibleTag(False)
|
|
|
|
def handlePossibleEndTag(self):
|
|
next(self.data)
|
|
return self.handlePossibleTag(True)
|
|
|
|
def handlePossibleTag(self, endTag):
|
|
data = self.data
|
|
if data.currentByte not in asciiLettersBytes:
|
|
# If the next byte is not an ascii letter either ignore this
|
|
# fragment (possible start tag case) or treat it according to
|
|
# handleOther
|
|
if endTag:
|
|
data.previous()
|
|
self.handleOther()
|
|
return True
|
|
|
|
c = data.skipUntil(spacesAngleBrackets)
|
|
if c == b"<":
|
|
# return to the first step in the overall "two step" algorithm
|
|
# reprocessing the < byte
|
|
data.previous()
|
|
else:
|
|
# Read all attributes
|
|
attr = self.getAttribute()
|
|
while attr is not None:
|
|
attr = self.getAttribute()
|
|
return True
|
|
|
|
def handleOther(self):
|
|
return self.data.jumpTo(b">")
|
|
|
|
def getAttribute(self):
|
|
"""Return a name,value pair for the next attribute in the stream,
|
|
if one is found, or None"""
|
|
data = self.data
|
|
# Step 1 (skip chars)
|
|
c = data.skip(spaceCharactersBytes | frozenset([b"/"]))
|
|
assert c is None or len(c) == 1
|
|
# Step 2
|
|
if c in (b">", None):
|
|
return None
|
|
# Step 3
|
|
attrName = []
|
|
attrValue = []
|
|
# Step 4 attribute name
|
|
while True:
|
|
if c == b"=" and attrName:
|
|
break
|
|
elif c in spaceCharactersBytes:
|
|
# Step 6!
|
|
c = data.skip()
|
|
break
|
|
elif c in (b"/", b">"):
|
|
return b"".join(attrName), b""
|
|
elif c in asciiUppercaseBytes:
|
|
attrName.append(c.lower())
|
|
elif c is None:
|
|
return None
|
|
else:
|
|
attrName.append(c)
|
|
# Step 5
|
|
c = next(data)
|
|
# Step 7
|
|
if c != b"=":
|
|
data.previous()
|
|
return b"".join(attrName), b""
|
|
# Step 8
|
|
next(data)
|
|
# Step 9
|
|
c = data.skip()
|
|
# Step 10
|
|
if c in (b"'", b'"'):
|
|
# 10.1
|
|
quoteChar = c
|
|
while True:
|
|
# 10.2
|
|
c = next(data)
|
|
# 10.3
|
|
if c == quoteChar:
|
|
next(data)
|
|
return b"".join(attrName), b"".join(attrValue)
|
|
# 10.4
|
|
elif c in asciiUppercaseBytes:
|
|
attrValue.append(c.lower())
|
|
# 10.5
|
|
else:
|
|
attrValue.append(c)
|
|
elif c == b">":
|
|
return b"".join(attrName), b""
|
|
elif c in asciiUppercaseBytes:
|
|
attrValue.append(c.lower())
|
|
elif c is None:
|
|
return None
|
|
else:
|
|
attrValue.append(c)
|
|
# Step 11
|
|
while True:
|
|
c = next(data)
|
|
if c in spacesAngleBrackets:
|
|
return b"".join(attrName), b"".join(attrValue)
|
|
elif c in asciiUppercaseBytes:
|
|
attrValue.append(c.lower())
|
|
elif c is None:
|
|
return None
|
|
else:
|
|
attrValue.append(c)
|
|
|
|
|
|
class ContentAttrParser(object):
|
|
def __init__(self, data):
|
|
assert isinstance(data, bytes)
|
|
self.data = data
|
|
|
|
def parse(self):
|
|
try:
|
|
# Check if the attr name is charset
|
|
# otherwise return
|
|
self.data.jumpTo(b"charset")
|
|
self.data.position += 1
|
|
self.data.skip()
|
|
if not self.data.currentByte == b"=":
|
|
# If there is no = sign keep looking for attrs
|
|
return None
|
|
self.data.position += 1
|
|
self.data.skip()
|
|
# Look for an encoding between matching quote marks
|
|
if self.data.currentByte in (b'"', b"'"):
|
|
quoteMark = self.data.currentByte
|
|
self.data.position += 1
|
|
oldPosition = self.data.position
|
|
if self.data.jumpTo(quoteMark):
|
|
return self.data[oldPosition:self.data.position]
|
|
else:
|
|
return None
|
|
else:
|
|
# Unquoted value
|
|
oldPosition = self.data.position
|
|
try:
|
|
self.data.skipUntil(spaceCharactersBytes)
|
|
return self.data[oldPosition:self.data.position]
|
|
except StopIteration:
|
|
# Return the whole remaining value
|
|
return self.data[oldPosition:]
|
|
except StopIteration:
|
|
return None
|
|
|
|
|
|
def lookupEncoding(encoding):
|
|
"""Return the python codec name corresponding to an encoding or None if the
|
|
string doesn't correspond to a valid encoding."""
|
|
if isinstance(encoding, bytes):
|
|
try:
|
|
encoding = encoding.decode("ascii")
|
|
except UnicodeDecodeError:
|
|
return None
|
|
|
|
if encoding is not None:
|
|
try:
|
|
return webencodings.lookup(encoding)
|
|
except AttributeError:
|
|
return None
|
|
else:
|
|
return None
|