bta-proxy/bta_proxy/datainputstream.py

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2023-08-24 15:29:57 +03:00
import struct
class DataInputStream:
def __init__(self, buffer: bytes):
self._buffer = buffer
self._cursor = 0
def read_bytes(self, n: int) -> bytes:
if self._cursor + n > len(self._buffer):
raise EOFError('stream overread')
blob = self._buffer[self._cursor : self._cursor + n]
self._cursor += n
return blob
def empty(self):
return self._cursor >= len(self._buffer) - 1
def end(self) -> bytes:
return self.read_bytes(len(self._buffer) - self._cursor)
def read_byte(self) -> int:
if self._cursor >= len(self._buffer):
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print(f'\033[91mstream overread in {self._buffer}\033[0m')
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raise EOFError('stream overread')
self._cursor += 1
return self._buffer[self._cursor - 1]
def read_boolean(self) -> bool:
return self.read_byte() != 0
def read_short(self) -> int:
return struct.unpack('>h', self.read_bytes(2))[0]
def read_ushort(self) -> int:
return struct.unpack('>H', self.read_bytes(2))[0]
def read_int(self) -> int:
return struct.unpack('>i', self.read_bytes(4))[0]
def read_uint(self) -> int:
return struct.unpack('>I', self.read_bytes(4))[0]
def read_long(self) -> int:
return struct.unpack('>q', self.read_bytes(8))[0]
def read_ulong(self) -> int:
return struct.unpack('>Q', self.read_bytes(8))[0]
def read_float(self) -> float:
return struct.unpack('>f', self.read_bytes(4))[0]
def read_double(self) -> float:
return struct.unpack('>d', self.read_bytes(8))[0]
def read_char(self) -> str:
return chr(self.read_ushort())
def read_varint(self, bits: int = 32) -> int:
value: int = 0
position: int = 0
while True:
byte = self.read_byte()
value |= (byte & 0x7F) << position
if ((byte & 0x80) == 0):
break
position += 7
if position >= bits:
raise ValueError('varint too big')
return value
def read_string(self) -> str:
size = self.read_short()
return self.read_bytes(size).decode('utf-8')