Method __call__

pager_lib/pyasn1/codec/ber/decoder.py:1563–1905

(self, substrate, asn1Spec=None,
                 tagSet=None, length=None, state=stDecodeTag,
                 decodeFun=None, substrateFun=None,
                 **options)

        self._tagSetCache = {}

    def __call__(self, substrate, asn1Spec=None,
                 tagSet=None, length=None, state=stDecodeTag,
                 decodeFun=None, substrateFun=None,
                 **options):

        allowEoo = options.pop('allowEoo', False)

        if LOG:
            LOG('decoder called at scope %s with state %d, working with up '
                'to %s octets of substrate: '
                '%s' % (debug.scope, state, length, substrate))

        # Look for end-of-octets sentinel
        if allowEoo and self.supportIndefLength:

            for eoo_candidate in readFromStream(substrate, 2, options):
                if isinstance(eoo_candidate, SubstrateUnderrunError):
                    yield eoo_candidate

            if eoo_candidate == EOO_SENTINEL:
                if LOG:
                    LOG('end-of-octets sentinel found')
                yield eoo.endOfOctets
                return

            else:
                substrate.seek(-2, os.SEEK_CUR)

        tagMap = self._tagMap
        typeMap = self._typeMap
        tagCache = self._tagCache
        tagSetCache = self._tagSetCache

        value = noValue

        substrate.markedPosition = substrate.tell()

        while state is not stStop:

            if state is stDecodeTag:
                # Decode tag
                isShortTag = True

                for firstByte in readFromStream(substrate, 1, options):
                    if isinstance(firstByte, SubstrateUnderrunError):
                        yield firstByte

                firstOctet = ord(firstByte)

                try:
                    lastTag = tagCache[firstOctet]

                except KeyError:
                    integerTag = firstOctet
                    tagClass = integerTag & 0xC0
                    tagFormat = integerTag & 0x20
                    tagId = integerTag & 0x1F