/**
* Return a protocol decoder's docstring.
*
- * @param dec The loaded protocol decoder.
+ * @param dec The loaded protocol decoder. Must not be NULL.
*
* @return A newly allocated buffer containing the protocol decoder's
* documentation. The caller is responsible for free'ing the buffer.
if (!srd_check_init())
return NULL;
- if (!dec)
+ if (!dec || !dec->py_mod)
return NULL;
gstate = PyGILState_Ensure();