Changeset b1261cb in mod_gnutls

Timestamp:

Dec 12, 2019, 4:58:01 PM (4 months ago)

Author:

Fiona Klute <fiona.klute@…>

Branches:

master

Children:

f3a3f6f

Parents:

4459cdd

Message:

mgstest: Context manager for an optional file-based mutex

This can be used to replace the various flock instances in runtests,
and possibly the .NOPARALLEL mode too, if the lockf-based emulation
mentioned in the Python documentation supports all relevant platforms.

File:

• test/mgstest/__init__.py (modified) (1 diff)

test/mgstest/__init__.py

@@ -17 +17 @@
 """Python modules for the mod_gnutls test suite."""
 
+import sys
+
+import fcntl
+from contextlib import contextmanager
+
 class TestExpectationFailed(Exception):
     """Raise if a test failed. The constructor should be called with a
     string describing the problem."""
     pass
+
+
+
+@contextmanager
+def lockfile(file, nolock=False):
+    """Context manager for an optional file-based mutex.
+
+    Unless nolock=True the process must hold a lock on the given file
+    before entering the context. The lock is released when leaving the
+    context.
+
+    """
+    if nolock:
+        yield
+    else:
+        with open(file, 'w') as lockfile:
+            try:
+                print(f'Aquiring lock on {file}...', file=sys.stderr)
+                fcntl.flock(lockfile, fcntl.LOCK_EX)
+                print(f'Got lock on {file}.', file=sys.stderr)
+                yield
+            finally:
+                print(f'Unlocking {file}...', file=sys.stderr)
+                fcntl.flock(lockfile, fcntl.LOCK_UN)
+                print(f'Unlocked {file}.', file=sys.stderr)