Source code for rwlock.user

"""
Module **sesf.rwlock.user** has class ``User`` that implements a user of
the read-write-lock service. To drive a rwlock implementation, run

"``python user.py <num_threads> <num_ops> <rwl_imp>``"

where ``<rwl_imp>`` is the implementation module and any command line
arguments (eg, ``imp_0.imp``), to drive the implementation with
``num_threads`` user threads, each issuing ``num_ops`` read or write
(randomly chosen) operations.
"""

# from threading import Thread, Lock, Condition
from threading import Thread, get_ident
import importlib, random, time, sys, argparse

class User():

  def __init__(self, argv):
    print('starting rwlock.user', argv, flush=True)
    p = argparse.ArgumentParser(
      usage='python user.py [-h] num_threads num_ops rwlock',
      description='create a user to drive the given rwlock implementation')
    p.add_argument("num_threads", type=int, help='number of user threads')
    p.add_argument("num_ops", type=int,
                   help='number of read or write operations per thread')
    p.add_argument("rwlock", nargs=argparse.REMAINDER,
                   help='rwlock implementation module and any args')
    args = p.parse_args(argv[1:])
    print("rwlockuser args:", args)
    self.num_threads = args.num_threads
    self.num_ops = args.num_ops
    self.user_threads = []
    self.using_service_imp = False
    rwlmodule = importlib.import_module(args.rwlock[0])
    # if hasattr(rwlmodule, 'Service'):
    #  self.using_service_imp = True
    #  rwl_imp = rwlmodule.Service()
    # elif len(args.rwlock) == 1:
    if len(args.rwlock) == 1:
      rwl_imp = rwlmodule.Imp()
    else:
      rwl_imp = rwlmodule.Imp(args.rwlock)
    print("rwlock", rwl_imp)
    self.imp = rwl_imp
    for j in range(self.num_threads):
      t = Thread(target=self.do_rwops)
      self.user_threads.append(t)
      t.start()

  def do_rwops(self):
    tid = get_ident()
    print('starting user thread', tid, 'doing',
          self.num_ops, 'reads or writes')
    for k in range(self.num_ops):
      time.sleep(random.random()*1)
      # randomly select read or write operation
      if random.randint(0, 1):
        self.imp.acqr()
        print('thread', tid, 'acqr')
        time.sleep(random.random()*2)
        print('thread', tid, 'relr')
        self.imp.relr()
      else:
        self.imp.acqw()
        print('thread', tid, 'acqw')
        time.sleep(random.random()*1)
        self.imp.relw()
        print('thread', tid, 'relw')

if __name__ == '__main__':
  rwlock_user = User(sys.argv)
  # if rwlock_user.imp has __end__ (ie, is service_imp), end service process
  if hasattr(rwlock_user.imp, '__end__'):
    for t in rwlock_user.user_threads:
      t.join()
    rwlock_user.imp.__end__()