lldb/packages/Python/lldbsuite/test/lock.py

   1 """
   2 Interprocess mutex based on file locks
   3 """
   4
   5 import fcntl
   6
   7
   8 class Lock:
   9
  10     def __init__(self, filename):
  11         self.filename = filename
  12         # This will create it if it does not exist already
  13         unbuffered = 0
  14         self.handle = open(filename, 'a+', unbuffered)
  15
  16     def acquire(self):
  17         fcntl.flock(self.handle, fcntl.LOCK_EX)
  18
  19     # will throw IOError if unavailable
  20     def try_acquire(self):
  21         fcntl.flock(self.handle, fcntl.LOCK_NB | fcntl.LOCK_EX)
  22
  23     def release(self):
  24         fcntl.flock(self.handle, fcntl.LOCK_UN)
  25
  26     def __del__(self):
  27         self.handle.close()