Microsoft Unix Rand / Srand implementation

microsoft_rand_prng.py

class microsoft_rand_prng:
  """
  Microsoft implementation of the srand and rand PRNG functions.
  https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/srand?view=vs-2019
  https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/rand?view=vs-2019
  
  srand and rand functions are present on ucrtbase.dll
  """
  def __init__(self): 
    self._seed = 0 

  def srand(self, seed): 
    self._seed = seed 

  def rand(self): 
    n = self._seed * 0x343fd + 0x269ec3 
    self._seed = n & 0xffffffff 
    return (n>>16) & 0x7fff