diff options
| -rw-r--r-- | lib/spack/llnl/util/lock.py | 36 | ||||
| -rw-r--r-- | lib/spack/spack/test/lock.py | 2 |
2 files changed, 20 insertions, 18 deletions
diff --git a/lib/spack/llnl/util/lock.py b/lib/spack/llnl/util/lock.py index 2cde389bd2..ce31a59d62 100644 --- a/lib/spack/llnl/util/lock.py +++ b/lib/spack/llnl/util/lock.py @@ -54,7 +54,7 @@ class Lock(object): def __init__(self, file_path): self._file_path = file_path - self._fd = None + self._file = None self._reads = 0 self._writes = 0 @@ -75,21 +75,23 @@ class Lock(object): try: # If this is already open read-only and we want to # upgrade to an exclusive write lock, close first. - if self._fd is not None: - flags = fcntl.fcntl(self._fd, fcntl.F_GETFL) - if op == fcntl.LOCK_EX and flags | os.O_RDONLY: - os.close(self._fd) - self._fd = None - - if self._fd is None: - mode = os.O_RDWR if op == fcntl.LOCK_EX else os.O_RDONLY - self._fd = os.open(self._file_path, mode) - - fcntl.lockf(self._fd, op | fcntl.LOCK_NB) + if self._file is not None: + if op == fcntl.LOCK_EX and self._file.mode == 'r': + self._file.close() + self._file = None + + # Open reader locks read-only if possible. + # lock doesn't exist, open RW + create if it doesn't exist. + if self._file is None: + mode = 'r+' if op == fcntl.LOCK_EX else 'r' + self._file = open(self._file_path, mode) + + fcntl.lockf(self._file, op | fcntl.LOCK_NB) if op == fcntl.LOCK_EX: - os.write( - self._fd, + self._file.write( "pid=%s,host=%s" % (os.getpid(), socket.getfqdn())) + self._file.truncate() + self._file.flush() return except IOError as error: @@ -108,9 +110,9 @@ class Lock(object): be masquerading as write locks, but this removes either. """ - fcntl.lockf(self._fd, fcntl.LOCK_UN) - os.close(self._fd) - self._fd = None + fcntl.lockf(self._file, fcntl.LOCK_UN) + self._file.close() + self._file = None def acquire_read(self, timeout=_default_timeout): """Acquires a recursive, shared lock for reading. diff --git a/lib/spack/spack/test/lock.py b/lib/spack/spack/test/lock.py index 32cbe13ce1..30b7dbce0e 100644 --- a/lib/spack/spack/test/lock.py +++ b/lib/spack/spack/test/lock.py @@ -184,7 +184,7 @@ class LockTest(unittest.TestCase): lock.release_read() self.assertTrue(lock._reads == 0) self.assertTrue(lock._writes == 0) - self.assertTrue(lock._fd is None) + self.assertTrue(lock._file is None) # # Longer test case that ensures locks are reusable. Ordering is |