Skip to main content

Python Convert bytes to ctypes.Structure


bytes -> ctyeps.Structure​

from ctypes import c_int16, c_int32, memmove, pointer, sizeof, Structure


class Data(Structure):
    # |  a  |  b  |     c     |
    #  XX XX XX XX XX XX XX XX

    _fields_ = [
        ("a", c_int16),
        ("b", c_int16),
        ("c", c_int32),
    ]


# Little-endian
# 0x0001 => 0x01 0x00
# 0x0002 => 0x02 0x00
# 0x00000003 => 0x03 0x00 0x00 0x00
dataBytes = bytes([1, 0, 2, 0, 3, 0, 0, 0])
dataSturct = Data()

memmove(pointer(dataSturct), dataBytes, sizeof(dataSturct))

assert dataSturct.a == 1
assert dataSturct.b == 2
assert dataSturct.c == 3

ctypes.Structure -> bytes​

from ctypes import c_int16, c_int32, memmove, pointer, sizeof, Structure


class Data(Structure):
    # |  a  |  b  |     c     |
    #  XX XX XX XX XX XX XX XX

    _fields_ = [
        ("a", c_int16),
        ("b", c_int16),
        ("c", c_int32),
    ]


# Little-endian
# 0x0001 => 0x01 0x00
# 0x0002 => 0x02 0x00
# 0x00000003 => 0x03 0x00 0x00 0x00
dataSturct = Data(a=1, b=2, c=3)

dataBytes = bytes(dataSturct)

assert dataBytes[0] == 1
assert dataBytes[2] == 2
assert dataBytes[4] == 3