From 34450c11255f7ae19ecda92f9bb4ff2b5adf498b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Luk=C3=A1=C5=A1=20Hr=C3=A1zk=C3=BD?= <lhrazky@redhat.com>
Date: Thu, 16 Jan 2020 16:36:11 +0100
Subject: [PATCH] Fix calling Python API without holding GIL (RhBug:1788918)

Librepo releases GIL for the download operations, but it wasn't taking
it again early enough in some callbacks where Python API is being called.

This commit moves taking the GIL in the callbacks to before any Python
API is called.

https://bugzilla.redhat.com/show_bug.cgi?id=1788918
---
 librepo/python/handle-py.c         | 6 ++++--
 librepo/python/metadatatarget-py.c | 6 ++++--
 librepo/python/packagetarget-py.c  | 6 ++++--
 3 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/librepo/python/handle-py.c b/librepo/python/handle-py.c
index 28aad87..02615ad 100644
--- a/librepo/python/handle-py.c
+++ b/librepo/python/handle-py.c
@@ -142,6 +142,8 @@ fastestmirror_callback(void *data, LrFastestMirrorStages stage, void *ptr)
     else
         user_data = Py_None;
 
+    EndAllowThreads(self->state);
+
     if (!ptr) {
         pydata = Py_None;
     } else {
@@ -159,7 +161,6 @@ fastestmirror_callback(void *data, LrFastestMirrorStages stage, void *ptr)
         }
     }
 
-    EndAllowThreads(self->state);
     result = PyObject_CallFunction(self->fastestmirror_cb,
                         "(OlO)", user_data, (long) stage, pydata);
     Py_XDECREF(result);
@@ -187,11 +188,12 @@ hmf_callback(void *data, const char *msg, const char *url, const char *metadata)
     else
         user_data = Py_None;
 
+    EndAllowThreads(self->state);
+
     py_msg = PyStringOrNone_FromString(msg);
     py_url = PyStringOrNone_FromString(url);
     py_metadata = PyStringOrNone_FromString(metadata);
 
-    EndAllowThreads(self->state);
     result = PyObject_CallFunction(self->hmf_cb,
                         "(OOOO)", user_data, py_msg, py_url, py_metadata);
 
diff --git a/librepo/python/metadatatarget-py.c b/librepo/python/metadatatarget-py.c
index d5f4088..4cb67ad 100644
--- a/librepo/python/metadatatarget-py.c
+++ b/librepo/python/metadatatarget-py.c
@@ -142,10 +142,11 @@ metadatatarget_mirrorfailure_callback(void *data,
     else
         user_data = Py_None;
 
+    EndAllowThreads(self->state);
+
     py_msg = PyStringOrNone_FromString(msg);
     py_url = PyStringOrNone_FromString(url);
 
-    EndAllowThreads(self->state);
     result = PyObject_CallFunction(self->mirrorfailure_cb,
                                    "(OOO)", user_data, py_msg, py_url);
 
@@ -205,9 +206,10 @@ metadatatarget_end_callback(void *data,
     else
         user_data = Py_None;
 
+    EndAllowThreads(self->state);
+
     py_msg = PyStringOrNone_FromString(msg);
 
-    EndAllowThreads(self->state);
     result = PyObject_CallFunction(self->end_cb,
                                    "(OiO)", user_data, status, py_msg);
     Py_DECREF(py_msg);
diff --git a/librepo/python/packagetarget-py.c b/librepo/python/packagetarget-py.c
index 839ec8c..f5182dd 100644
--- a/librepo/python/packagetarget-py.c
+++ b/librepo/python/packagetarget-py.c
@@ -134,9 +134,10 @@ packagetarget_end_callback(void *data,
     else
         user_data = Py_None;
 
+    EndAllowThreads(self->state);
+
     py_msg = PyStringOrNone_FromString(msg);
 
-    EndAllowThreads(self->state);
     result = PyObject_CallFunction(self->end_cb,
                                    "(OiO)", user_data, status, py_msg);
     Py_DECREF(py_msg);
@@ -185,10 +186,11 @@ packagetarget_mirrorfailure_callback(void *data,
     else
         user_data = Py_None;
 
+    EndAllowThreads(self->state);
+
     py_msg = PyStringOrNone_FromString(msg);
     py_url = PyStringOrNone_FromString(url);
 
-    EndAllowThreads(self->state);
     result = PyObject_CallFunction(self->mirrorfailure_cb,
                                    "(OOO)", user_data, py_msg, py_url);