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# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
from pkg_resources import parse_version
from .kaitaistruct import __version__ as ks_version, KaitaiStruct, KaitaiStream, BytesIO
import collections
if parse_version(ks_version) < parse_version('0.7'):
raise Exception("Incompatible Kaitai Struct Python API: 0.7 or later is required, but you have %s" % (ks_version))
class VlqBase128Be(KaitaiStruct):
"""A variable-length unsigned integer using base128 encoding. 1-byte groups
consist of 1-bit flag of continuation and 7-bit value chunk, and are ordered
"most significant group first", i.e. in "big-endian" manner.
This particular encoding is specified and used in:
* Standard MIDI file format
* ASN.1 BER encoding
More information on this encoding is available at
https://en.wikipedia.org/wiki/Variable-length_quantity
This particular implementation supports serialized values to up 8 bytes long.
"""
SEQ_FIELDS = ["groups"]
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._debug = collections.defaultdict(dict)
def _read(self):
self._debug['groups']['start'] = self._io.pos()
self.groups = []
i = 0
while True:
if not 'arr' in self._debug['groups']:
self._debug['groups']['arr'] = []
self._debug['groups']['arr'].append({'start': self._io.pos()})
_t_groups = self._root.Group(self._io, self, self._root)
_t_groups._read()
_ = _t_groups
self.groups.append(_)
self._debug['groups']['arr'][len(self.groups) - 1]['end'] = self._io.pos()
if not (_.has_next):
break
i += 1
self._debug['groups']['end'] = self._io.pos()
class Group(KaitaiStruct):
"""One byte group, clearly divided into 7-bit "value" chunk and 1-bit "continuation" flag.
"""
SEQ_FIELDS = ["b"]
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._debug = collections.defaultdict(dict)
def _read(self):
self._debug['b']['start'] = self._io.pos()
self.b = self._io.read_u1()
self._debug['b']['end'] = self._io.pos()
@property
def has_next(self):
"""If true, then we have more bytes to read."""
if hasattr(self, '_m_has_next'):
return self._m_has_next if hasattr(self, '_m_has_next') else None
self._m_has_next = (self.b & 128) != 0
return self._m_has_next if hasattr(self, '_m_has_next') else None
@property
def value(self):
"""The 7-bit (base128) numeric value chunk of this group."""
if hasattr(self, '_m_value'):
return self._m_value if hasattr(self, '_m_value') else None
self._m_value = (self.b & 127)
return self._m_value if hasattr(self, '_m_value') else None
@property
def last(self):
if hasattr(self, '_m_last'):
return self._m_last if hasattr(self, '_m_last') else None
self._m_last = (len(self.groups) - 1)
return self._m_last if hasattr(self, '_m_last') else None
@property
def value(self):
"""Resulting value as normal integer."""
if hasattr(self, '_m_value'):
return self._m_value if hasattr(self, '_m_value') else None
self._m_value = (((((((self.groups[self.last].value + ((self.groups[(self.last - 1)].value << 7) if self.last >= 1 else 0)) + ((self.groups[(self.last - 2)].value << 14) if self.last >= 2 else 0)) + ((self.groups[(self.last - 3)].value << 21) if self.last >= 3 else 0)) + ((self.groups[(self.last - 4)].value << 28) if self.last >= 4 else 0)) + ((self.groups[(self.last - 5)].value << 35) if self.last >= 5 else 0)) + ((self.groups[(self.last - 6)].value << 42) if self.last >= 6 else 0)) + ((self.groups[(self.last - 7)].value << 49) if self.last >= 7 else 0))
return self._m_value if hasattr(self, '_m_value') else None
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