From cfd3bcb21eeec8b81ea41f706b6bdb87ac034b1a Mon Sep 17 00:00:00 2001
From: Christian McDonald <cmcdonald@netgate.com>
Date: Fri, 13 Jan 2023 16:39:28 -0500
Subject: [PATCH] eliminate unnecessary Python reloading which causes memory
 leaks

---
 pythonmod/pythonmod.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/pythonmod/pythonmod.c b/pythonmod/pythonmod.c
index 28ce0eec4..19b464633 100644
--- a/pythonmod/pythonmod.c
+++ b/pythonmod/pythonmod.c
@@ -252,6 +252,16 @@ cleanup:
 	Py_XDECREF(exc_tb);
 }
 
+/* we only want to unwind Python once at exit */
+void pythonmod_atexit(void)
+{
+   assert(py_mod_count == 0);
+   assert(maimthr != NULL);
+ 
+   PyEval_RestoreThread(mainthr);
+   Py_Finalize();
+}
+
 int pythonmod_init(struct module_env* env, int id)
 {
    int py_mod_idx = py_mod_count++;
@@ -310,6 +320,9 @@ int pythonmod_init(struct module_env* env, int id)
 #endif
       SWIG_init();
       mainthr = PyEval_SaveThread();
+
+      /* XXX: register callback to unwind Python at exit */
+      atexit(pythonmod_atexit);
    }
 
    gil = PyGILState_Ensure();
@@ -547,11 +560,7 @@ void pythonmod_deinit(struct module_env* env, int id)
       Py_XDECREF(pe->data);
       PyGILState_Release(gil);
 
-      if(--py_mod_count==0) {
-         PyEval_RestoreThread(mainthr);
-         Py_Finalize();
-         mainthr = NULL;
-      }
+      py_mod_count--;
    }
    pe->fname = NULL;
    free(pe);