Fixed database typo and removed unnecessary class identifier.

venv/Lib/site-packages/scipy/_lib/_threadsafety.py

@@ -0,0 +1,58 @@
+import threading
+
+import scipy._lib.decorator
+
+
+__all__ = ['ReentrancyError', 'ReentrancyLock', 'non_reentrant']
+
+
+class ReentrancyError(RuntimeError):
+    pass
+
+
+class ReentrancyLock(object):
+    """
+    Threading lock that raises an exception for reentrant calls.
+
+    Calls from different threads are serialized, and nested calls from the
+    same thread result to an error.
+
+    The object can be used as a context manager or to decorate functions
+    via the decorate() method.
+
+    """
+
+    def __init__(self, err_msg):
+        self._rlock = threading.RLock()
+        self._entered = False
+        self._err_msg = err_msg
+
+    def __enter__(self):
+        self._rlock.acquire()
+        if self._entered:
+            self._rlock.release()
+            raise ReentrancyError(self._err_msg)
+        self._entered = True
+
+    def __exit__(self, type, value, traceback):
+        self._entered = False
+        self._rlock.release()
+
+    def decorate(self, func):
+        def caller(func, *a, **kw):
+            with self:
+                return func(*a, **kw)
+        return scipy._lib.decorator.decorate(func, caller)
+
+
+def non_reentrant(err_msg=None):
+    """
+    Decorate a function with a threading lock and prevent reentrant calls.
+    """
+    def decorator(func):
+        msg = err_msg
+        if msg is None:
+            msg = "%s is not re-entrant" % func.__name__
+        lock = ReentrancyLock(msg)
+        return lock.decorate(func)
+    return decorator