add RestoreStackFunc method for preventing stack leaks

1 files changed, 18 insertions, 0 deletions

diff --git a/lua.go b/lua.go
index 874dac8..9e7b6ec 100644
--- a/lua.go
+++ b/lua.go
@@ -122,3 +122,21 @@ func (l *Lua) PushTableItem (key string) {
 	C.lua_pushstring(l.l, ckey);
 	C.lua_gettable(l.l, -2);
 }
+
+func (l *Lua) RestoreStackFunc() func () {
+	before := l.StackLen()
+	return func () {
+		after := l.StackLen()
+		diff := after - before
+		if diff == 0 {
+			return
+		} else if diff < 0 {
+			log.Fatalf(
+				"too many stack pops: len before: %d, after: %d\n",
+				before,
+				after,
+			)
+		}
+		C.lua_settop(l.l, C.int(before))
+	}
+}