nbdkit/SOURCES/0012-python-Implement-.clea...

91 lines
2.5 KiB
Diff

From 17a912a449fa75b5c12ac3acab596b476699c671 Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjones@redhat.com>
Date: Tue, 3 Aug 2021 14:19:38 +0100
Subject: [PATCH] python: Implement .cleanup() method
(cherry picked from commit f2fe99e4b0f54467ab8028eaf2d039cf918b2961)
---
plugins/python/nbdkit-python-plugin.pod | 20 +++++++++++++++++---
plugins/python/plugin.c | 19 +++++++++++++++++++
2 files changed, 36 insertions(+), 3 deletions(-)
diff --git a/plugins/python/nbdkit-python-plugin.pod b/plugins/python/nbdkit-python-plugin.pod
index 6f5f2c00..a92a557f 100644
--- a/plugins/python/nbdkit-python-plugin.pod
+++ b/plugins/python/nbdkit-python-plugin.pod
@@ -257,6 +257,12 @@ There are no arguments or return value.
There are no arguments or return value.
+=item C<cleanup>
+
+(Optional, nbdkit E<ge> 1.28)
+
+There are no arguments or return value.
+
=item C<list_exports>
(Optional)
@@ -498,10 +504,18 @@ optionally using C<nbdkit.set_error> first.
=over 4
-=item Missing: C<load> and C<unload>
+=item Missing: C<load>
-These are not needed because you can just use ordinary Python
-constructs.
+This is not needed since you can use regular Python mechanisms like
+top level statements to run code when the module is loaded.
+
+=item Missing: C<unload>
+
+This is missing, but in nbdkit E<ge> 1.28 you can put code in the
+C<cleanup()> function to have it run when nbdkit exits. In earlier
+versions of nbdkit, using a Python
+L<atexit|https://docs.python.org/3/library/atexit.html> handler is
+recommended.
=item Missing:
C<name>,
diff --git a/plugins/python/plugin.c b/plugins/python/plugin.c
index 64430a1a..f85512b4 100644
--- a/plugins/python/plugin.c
+++ b/plugins/python/plugin.c
@@ -298,6 +298,24 @@ py_after_fork (void)
return 0;
}
+static void
+py_cleanup (void)
+{
+ ACQUIRE_PYTHON_GIL_FOR_CURRENT_SCOPE;
+ PyObject *fn;
+ PyObject *r;
+
+ if (callback_defined ("cleanup", &fn)) {
+ PyErr_Clear ();
+
+ r = PyObject_CallObject (fn, NULL);
+ Py_DECREF (fn);
+ if (check_python_failure ("cleanup") == -1)
+ return;
+ Py_DECREF (r);
+ }
+}
+
static int
py_list_exports (int readonly, int is_tls, struct nbdkit_exports *exports)
{
@@ -1039,6 +1057,7 @@ static struct nbdkit_plugin plugin = {
.thread_model = py_thread_model,
.get_ready = py_get_ready,
.after_fork = py_after_fork,
+ .cleanup = py_cleanup,
.list_exports = py_list_exports,
.default_export = py_default_export,
--
2.31.1