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-rw-r--r--jython-tosca-parser/src/main/resources/Lib/site-packages/pip/_vendor/html5lib/inputstream.py905
1 files changed, 905 insertions, 0 deletions
diff --git a/jython-tosca-parser/src/main/resources/Lib/site-packages/pip/_vendor/html5lib/inputstream.py b/jython-tosca-parser/src/main/resources/Lib/site-packages/pip/_vendor/html5lib/inputstream.py
new file mode 100644
index 0000000..dc39ad0
--- /dev/null
+++ b/jython-tosca-parser/src/main/resources/Lib/site-packages/pip/_vendor/html5lib/inputstream.py
@@ -0,0 +1,905 @@
+from __future__ import absolute_import, division, unicode_literals
+from pip._vendor.six import text_type
+
+import codecs
+import platform
+import re
+
+from .constants import EOF, spaceCharacters, asciiLetters, asciiUppercase
+from .constants import encodings, ReparseException
+from . import utils
+
+from io import StringIO
+
+try:
+ from io import BytesIO
+except ImportError:
+ BytesIO = StringIO
+
+try:
+ from io import BufferedIOBase
+except ImportError:
+ class BufferedIOBase(object):
+ pass
+
+# 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_template = "[\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%s]"
+
+if platform.python_implementation() == "Jython":
+ # Jython does not allow the use of solitary surrogate escapes
+ # (\uD800-\uDFFF) in literals or other usage. This is because it
+ # uses UTF-16, which is based on the use of such surrogates.
+ invalid_unicode_re = re.compile(invalid_unicode_template % "")
+else:
+ # Instead use one extra step of indirection and create surrogates with
+ # unichr
+ invalid_unicode_re = re.compile(invalid_unicode_template % (
+ "%s-%s" % (unichr(0xD800), unichr(0xDFFF)),))
+
+non_bmp_invalid_codepoints = set([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\u005B-\u0060\u007B-\u007E]")
+
+# Cache for charsUntil()
+charsUntilRegEx = {}
+
+
+class BufferedStream:
+ """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 -= pos
+ 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 "".join(rv)
+
+
+def HTMLInputStream(source, encoding=None, parseMeta=True, chardet=True):
+ if hasattr(source, "read"):
+ isUnicode = isinstance(source.read(0), text_type)
+ else:
+ isUnicode = isinstance(source, text_type)
+
+ if isUnicode:
+ if encoding is not None:
+ raise TypeError("Cannot explicitly set an encoding with a unicode string")
+
+ return HTMLUnicodeInputStream(source)
+ else:
+ return HTMLBinaryInputStream(source, encoding, parseMeta, chardet)
+
+
+class 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.
+
+ """
+
+ _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)
+
+ parseMeta - Look for a <meta> element containing encoding information
+
+ """
+
+ # Craziness
+ if platform.python_implementation() == "Jython":
+ # By its nature Jython's UTF-16 support does not allow
+ # surrogate errors, so no need to do this check.
+ self.reportCharacterErrors = None
+ self.replaceCharactersRegexp = None
+ elif len("\U0010FFFF") == 1:
+ self.reportCharacterErrors = self.characterErrorsUCS4
+ self.replaceCharactersRegexp = re.compile("{}".format(
+ "[{}-{}]".format(unichr(0xD800), unichr(0xDFFF))))
+ else:
+ self.reportCharacterErrors = self.characterErrorsUCS2
+ self.replaceCharactersRegexp = re.compile("{}".format(
+ "([{}-{}](?![{}-{})|(?<![{}-{}])[{}-{}])".format(
+ unichr(0xD800), unichr(0xDBFF), unichr(0xDC00), unichr(0xDFFF),
+ unichr(0xD800), unichr(0xDBFF), unichr(0xDC00), unichr(0xDFFF))))
+
+ # List of where new lines occur
+ self.newLines = [0]
+
+ self.charEncoding = ("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 platform.python_implementation() != "Jython":
+ # data is already Unicode, so Jython already has dealt
+ # with any surrogate character errors, no need to go here
+ self.reportCharacterErrors(data)
+
+ # Replace invalid characters
+ # Note U+0000 is dealt with in the tokenizer
+ data = self.replaceCharactersRegexp.sub("\ufffd", data)
+
+ 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 i 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 None:
+ 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, encoding=None, parseMeta=True, chardet=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)
+
+ parseMeta - Look for a <meta> element containing encoding information
+
+ """
+ # 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)
+
+ self.charEncoding = (codecName(encoding), "certain")
+
+ # Encoding Information
+ # Number of bytes to use when looking for a meta element with
+ # encoding information
+ self.numBytesMeta = 512
+ # Number of bytes to use when using detecting encoding using chardet
+ self.numBytesChardet = 100
+ # Encoding to use if no other information can be found
+ self.defaultEncoding = "windows-1252"
+
+ # Detect encoding iff no explicit "transport level" encoding is supplied
+ if (self.charEncoding[0] is None):
+ self.charEncoding = self.detectEncoding(parseMeta, chardet)
+
+ # Call superclass
+ self.reset()
+
+ def reset(self):
+ self.dataStream = codecs.getreader(self.charEncoding[0])(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:
+ stream = BufferedStream(stream)
+
+ return stream
+
+ def detectEncoding(self, parseMeta=True, chardet=True):
+ # First look for a BOM
+ # This will also read past the BOM if present
+ encoding = self.detectBOM()
+ confidence = "certain"
+ # If there is no BOM need to look for meta elements with encoding
+ # information
+ if encoding is None and parseMeta:
+ encoding = self.detectEncodingMeta()
+ confidence = "tentative"
+ # Guess with chardet, if avaliable
+ if encoding is None and chardet:
+ confidence = "tentative"
+ try:
+ try:
+ from charade.universaldetector import UniversalDetector
+ except ImportError:
+ from chardet.universaldetector import UniversalDetector
+ 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 = detector.result['encoding']
+ self.rawStream.seek(0)
+ except ImportError:
+ pass
+ # If all else fails use the default encoding
+ if encoding is None:
+ confidence = "tentative"
+ encoding = self.defaultEncoding
+
+ # Substitute for equivalent encodings:
+ encodingSub = {"iso-8859-1": "windows-1252"}
+
+ if encoding.lower() in encodingSub:
+ encoding = encodingSub[encoding.lower()]
+
+ return encoding, confidence
+
+ def changeEncoding(self, newEncoding):
+ assert self.charEncoding[1] != "certain"
+ newEncoding = codecName(newEncoding)
+ if newEncoding in ("utf-16", "utf-16-be", "utf-16-le"):
+ newEncoding = "utf-8"
+ if newEncoding is None:
+ return
+ elif newEncoding == self.charEncoding[0]:
+ self.charEncoding = (self.charEncoding[0], "certain")
+ else:
+ self.rawStream.seek(0)
+ self.reset()
+ self.charEncoding = (newEncoding, "certain")
+ 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-16-le', codecs.BOM_UTF16_BE: 'utf-16-be',
+ codecs.BOM_UTF32_LE: 'utf-32-le', codecs.BOM_UTF32_BE: 'utf-32-be'
+ }
+
+ # 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
+ self.rawStream.seek(encoding and seek or 0)
+
+ return encoding
+
+ 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 in ("utf-16", "utf-16-be", "utf-16-le"):
+ encoding = "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):
+ 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"""
+ p = self.position
+ data = self[p:p + len(bytes)]
+ rv = data.startswith(bytes)
+ 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"""
+ newPosition = self[self.position:].find(bytes)
+ if newPosition > -1:
+ # XXX: This is ugly, but I can't see a nicer way to fix this.
+ if self._position == -1:
+ self._position = 0
+ self._position += (newPosition + len(bytes) - 1)
+ return True
+ else:
+ raise StopIteration
+
+
+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):
+ methodDispatch = (
+ (b"<!--", self.handleComment),
+ (b"<meta", self.handleMeta),
+ (b"</", self.handlePossibleEndTag),
+ (b"<!", self.handleOther),
+ (b"<?", self.handleOther),
+ (b"<", self.handlePossibleStartTag))
+ for byte in self.data:
+ keepParsing = True
+ 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 = codecName(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 = codecName(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 codecName(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:
+ canonicalName = ascii_punctuation_re.sub("", encoding).lower()
+ return encodings.get(canonicalName, None)
+ else:
+ return None