From a5eeca0a5c425bd17f1d4dbf0633e1a4311cda71 Mon Sep 17 00:00:00 2001
From: Robin Dunn <robin@alldunn.com>
Date: Wed, 27 Sep 2017 19:17:19 -0700
Subject: [PATCH] Return None when trying to make a memoryview buffer with a
 NULL pointer

---
 src/wxpy_api.sip | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/src/wxpy_api.sip b/src/wxpy_api.sip
index d97d7861..fdc14ff7 100644
--- a/src/wxpy_api.sip
+++ b/src/wxpy_api.sip
@@ -453,12 +453,17 @@ bool i_wxPyCheckForApp(bool raiseException) {
 
 PyObject* i_wxPyMakeBuffer(void* ptr, Py_ssize_t len, bool readOnly=false) {
     // GIL should already be held
-    Py_buffer view;
-    int flags = PyBUF_FORMAT|PyBUF_ND;
-    if (!readOnly)
-        flags |= PyBUF_WRITABLE;
-    PyBuffer_FillInfo(&view, NULL, ptr, len, readOnly ? 1:0, flags);
-    return PyMemoryView_FromBuffer(&view);
+    if (ptr && len) {
+        Py_buffer view;
+        int flags = PyBUF_FORMAT|PyBUF_ND;
+        if (!readOnly)
+            flags |= PyBUF_WRITABLE;
+        PyBuffer_FillInfo(&view, NULL, ptr, len, readOnly ? 1:0, flags);
+        return PyMemoryView_FromBuffer(&view);
+    } else {
+        Py_INCREF(Py_None); return Py_None;
+        // return PyBytes_FromString("");    TODO: None or an empty string?
+    }
 
 //    // TODO: Consider using a sip.array object instead, like this:
 //    // Create a sip.array of bytes, and then convert to a memoryview which is