new function RNA_warning(), replaces printf with function which may be called via python.

Now this gives the line number of the scripts thats running, eg:

uiItemFullO: unknown operator 'some.operator'
/c/bin/2.56/scripts/startup/bl_ui/space_view3d_toolbar.py:73

source/blender/python/generic/py_capi_utils.c

@@ -30,6 +30,8 @@
 
 #include "py_capi_utils.h"
 
+#define PYC_INTERPRETER_ACTIVE (((PyThreadState*)_Py_atomic_load_relaxed(&_PyThreadState_Current)) != NULL)
+
 /* for debugging */
 void PyC_ObSpit(const char *name, PyObject *var) {
 	fprintf(stderr, "<%s> : ", name);
@@ -51,9 +53,16 @@ void PyC_ObSpit(const char *name, PyObject *var) {
 }
 
 void PyC_LineSpit(void) {
+
 	const char *filename;
 	int lineno;
 
+	/* Note, allow calling from outside python (RNA) */
+	if(!PYC_INTERPRETER_ACTIVE) {
+		fprintf(stderr, "python line lookup failed, interpreter inactive\n");
+		return;
+	}
+
 	PyErr_Clear();
 	PyC_FileAndNum(&filename, &lineno);
 	

source/blender/python/generic/py_capi_utils.h

@@ -47,4 +47,5 @@ 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