--- a/util-src/strbitop.c	Thu Oct 15 17:05:53 2020 +0200
+++ b/util-src/strbitop.c	Thu Oct 15 17:12:33 2020 +0200
@@ -2,7 +2,7 @@
  * This project is MIT licensed. Please see the
  * COPYING file in the source package for more information.
  *
- * Copyright (C) 2016-2020 Kim Alvefur
+ * Copyright (C) 2016 Kim Alvefur
  */
 
 #include <lua.h>
@@ -25,13 +25,10 @@
 		return 1;
 	}
 
-	char *cbuf = luaL_buffinitsize(L, &buf, a);
-
 	for(i = 0; i < a; i++) {
-		cbuf[i] = str_a[i] & str_b[i % b];
+		luaL_addchar(&buf, str_a[i] & str_b[i % b]);
 	}
 
-	luaL_addsize(&buf, a);
 	luaL_pushresult(&buf);
 	return 1;
 }
@@ -47,13 +44,10 @@
 		return 1;
 	}
 
-	char *cbuf = luaL_buffinitsize(L, &buf, a);
-
 	for(i = 0; i < a; i++) {
-		cbuf[i] = str_a[i] | str_b[i % b];
+		luaL_addchar(&buf, str_a[i] | str_b[i % b]);
 	}
 
-	luaL_addsize(&buf, a);
 	luaL_pushresult(&buf);
 	return 1;
 }
@@ -64,18 +58,17 @@
 	const char *str_a = luaL_checklstring(L, 1, &a);
 	const char *str_b = luaL_checklstring(L, 2, &b);
 
+	luaL_buffinit(L, &buf);
+
 	if(a == 0 || b == 0) {
 		lua_settop(L, 1);
 		return 1;
 	}
 
-	char *cbuf = luaL_buffinitsize(L, &buf, a);
-
 	for(i = 0; i < a; i++) {
-		cbuf[i] = str_a[i] ^ str_b[i % b];
+		luaL_addchar(&buf, str_a[i] ^ str_b[i % b]);
 	}
 
-	luaL_addsize(&buf, a);
 	luaL_pushresult(&buf);
 	return 1;
 }