diff options
Diffstat (limited to 'lib/spack/llnl/util/lock.py')
-rw-r--r-- | lib/spack/llnl/util/lock.py | 30 |
1 files changed, 21 insertions, 9 deletions
diff --git a/lib/spack/llnl/util/lock.py b/lib/spack/llnl/util/lock.py index bb3b15c9cf..3cd02befe5 100644 --- a/lib/spack/llnl/util/lock.py +++ b/lib/spack/llnl/util/lock.py @@ -29,13 +29,15 @@ import errno import time import socket +# Default timeout for locks. +DEFAULT_TIMEOUT = 60 + +class _ReadLockContext(object): + """Context manager that takes and releases a read lock. -class Read_Lock_Instance(object): - """ - A context manager for getting shared access to the object lock Arguments are lock and timeout (default 5 minutes) """ - def __init__(self, lock, timeout=300): + def __init__(self, lock, timeout=DEFAULT_TIMEOUT): self._lock = lock self._timeout = timeout @@ -46,12 +48,12 @@ class Read_Lock_Instance(object): self._lock.release_read() -class Write_Lock_Instance(object): - """ - A context manager for getting exclusive access to the object lock +class _WriteLockContext(object): + """Context manager that takes and releases a write lock. + Arguments are lock and timeout (default 5 minutes) """ - def __init__(self, lock, timeout=300): + def __init__(self, lock, timeout=DEFAULT_TIMEOUT): self._lock = lock self._timeout = timeout @@ -72,7 +74,17 @@ class Lock(object): self._writes = 0 - def acquire_read(self,timeout): + def write_lock(self, timeout=DEFAULT_TIMEOUT): + """Convenience method that returns a write lock context.""" + return _WriteLockContext(self, timeout) + + + def read_lock(self, timeout=DEFAULT_TIMEOUT): + """Convenience method that returns a read lock context.""" + return _ReadLockContext(self, timeout) + + + def acquire_read(self, timeout): """ Implements recursive lock. If held in both read and write mode, the write lock will be maintained until all locks are released |