correct fix for bug #23871, __main__ module was being overwritten in nested functions, so on returning from calling operators the __main__ module could be cleared and imported modules turn into None

calling
  bpy.ops.wm.read_factory_settings()
... would clear a scripts namespace if running directly, not in a module.


Fix by backing up and restoring the __main__ module.

Also found BKE_reportf wasnt printing all reports in background mode as BKE_report() was doing.

2 files changed, 21 insertions, 0 deletions

diff --git a/source/blender/python/generic/py_capi_utils.c b/source/blender/python/generic/py_capi_utils.c
index d29587a084b..9f7a9f2cabe 100644
--- a/source/blender/python/generic/py_capi_utils.c
+++ b/source/blender/python/generic/py_capi_utils.c
@@ -282,6 +282,10 @@ PyObject *PyC_UnicodeFromByte(const char *str)
   for 'pickle' to work as well as strings like this...
  >> foo = 10
  >> print(__import__("__main__").foo)
+*
+* note: this overwrites __main__ which gives problems with nested calles.
+* be sure to run PyC_MainModule_Backup & PyC_MainModule_Restore if there is
+* any chance that python is in the call stack.
 *****************************************************************************/
 PyObject *PyC_DefaultNameSpace(const char *filename)
 {
@@ -297,6 +301,20 @@ PyObject *PyC_DefaultNameSpace(const char *filename)
 	return PyModule_GetDict(mod_main);
 }
 
+/* restore MUST be called after this */
+void PyC_MainModule_Backup(PyObject **main_mod)
+{
+	PyInterpreterState *interp= PyThreadState_GET()->interp;
+	*main_mod= PyDict_GetItemString(interp->modules, "__main__");
+	Py_XINCREF(*main_mod); /* dont free */
+}
+
+void PyC_MainModule_Restore(PyObject *main_mod)
+{
+	PyInterpreterState *interp= PyThreadState_GET()->interp;
+	PyDict_SetItemString(interp->modules, "__main__", main_mod);
+	Py_XDECREF(main_mod);
+}
 
 /* Would be nice if python had this built in */
 void PyC_RunQuicky(const char *filepath, int n, ...)
diff --git a/source/blender/python/generic/py_capi_utils.h b/source/blender/python/generic/py_capi_utils.h
index f786fd80269..ccdbde5cecb 100644
--- a/source/blender/python/generic/py_capi_utils.h
+++ b/source/blender/python/generic/py_capi_utils.h
@@ -39,4 +39,7 @@ const char *	PyC_UnicodeAsByte(PyObject *py_str, PyObject **coerce); /* coerce m
 /* name namespace function for bpy & bge */
 PyObject *		PyC_DefaultNameSpace(const char *filename);
 void			PyC_RunQuicky(const char *filepath, int n, ...);
+
+void PyC_MainModule_Backup(PyObject **main_mod);
+void PyC_MainModule_Restore(PyObject *main_mod);
 #endif // PY_CAPI_UTILS_H