Add 's'/'z' case to do_mkvalue

src/capi/modsupport.cpp

@@ -125,6 +125,36 @@ static PyObject* do_mkvalue(const char** p_format, va_list* p_va, int flags) noe
                     return v;
                 }
 
+            case 's':
+            case 'z': {
+                PyObject* v;
+                char* str = va_arg(*p_va, char*);
+                Py_ssize_t n;
+                if (**p_format == '#') {
+                    ++*p_format;
+                    if (flags & FLAG_SIZE_T)
+                        n = va_arg(*p_va, Py_ssize_t);
+                    else
+                        n = va_arg(*p_va, int);
+                } else
+                    n = -1;
+                if (str == NULL) {
+                    v = Py_None;
+                    Py_INCREF(v);
+                } else {
+                    if (n < 0) {
+                        size_t m = strlen(str);
+                        if (m > PY_SSIZE_T_MAX) {
+                            PyErr_SetString(PyExc_OverflowError, "string too long for Python string");
+                            return NULL;
+                        }
+                        n = (Py_ssize_t)m;
+                    }
+                    v = PyString_FromStringAndSize(str, n);
+                }
+                return v;
+            }
+
             default:
                 RELEASE_ASSERT(0, "%c", *((*p_format) - 1));
         }