integerencoder.py

#!/usr/bin/env python
# Author Dario Clavijo 2018

import struct


def uint32tobytes(value, big_endian=True):
    return struct.pack(">I", value) if big_endian else struct.pack("<I", value)


def bytestouint32(value, big_endian=True):
    if big_endian:
        return struct.unpack(">I", value)[0]
    else:
        return struct.unpack("<I", value)[0]


def int32tobytes(value, big_endian=True):
    return struct.pack(">i", value) if big_endian else struct.pack("<i", value)


def bytestoint32(value, big_endian=True):
    if big_endian:
        return struct.unpack(">i", value)[0]
    else:
        return struct.unpack("<i", value)[0]


def test1():
    print((uint32tobytes(0).encode("hex")))
    print((uint32tobytes(1).encode("hex")))
    print((uint32tobytes(0, False).encode("hex")))
    print((uint32tobytes(1, False).encode("hex")))

    print((int32tobytes(0).encode("hex")))
    print((int32tobytes(-1).encode("hex")))
    print((int32tobytes(0, False).encode("hex")))
    print((int32tobytes(-1, False).encode("hex")))


def test2():
    print((bytestoint32(int32tobytes(c[0] + c[1]))))


# test1()
# test2()

regs = [0 * 31]
regs[0] = int32tobytes(-1)
print(regs)
a = (bytestouint32(regs[0]) >> 1) & 0xFFFFFFFF
b = (bytestouint32(regs[0]) << 1) & 0xFFFFFFFF
# print len(a),len(b)
print(a, b)
print(hex(a), hex(b))
print(uint32tobytes(a).encode("hex"))
print(int32tobytes(a).encode("hex"))

print(uint32tobytes(b).encode("hex"))
print(int32tobytes(b).encode("hex"))


# print(a << 1)