add small stack type (#1422)

Author: paulwe

.changeset/gold-fishes-smash.md

@@ -0,0 +1,5 @@
+---
+"@livekit/protocol": patch
+---
+
+add stack utility

utils/closers.go

@@ -16,6 +16,7 @@ package utils
 
 import (
 	"io"
+	"slices"
 
 	"go.uber.org/multierr"
 )
@@ -28,7 +29,7 @@ func CombineClosers(cs ...io.Closer) Closers {
 
 func (s *Closers) Close() error {
 	var err error
-	for _, c := range *s {
+	for _, c := range slices.Backward(*s) {
 		if c != nil {
 			err = multierr.Append(err, c.Close())
 		}

utils/stack/stack.go

@@ -0,0 +1,25 @@
+package stack
+
+type Stack[T any] []T
+
+func (s Stack[T]) Empty() bool {
+	return len(s) == 0
+}
+
+func (s *Stack[T]) Reset() {
+	*s = (*s)[:0]
+}
+
+func (s *Stack[T]) Push(v T) {
+	*s = append(*s, v)
+}
+
+func (s *Stack[T]) Pop() T {
+	v := (*s)[len(*s)-1]
+	*s = (*s)[:len(*s)-1]
+	return v
+}
+
+func (s Stack[T]) Peek() T {
+	return s[len(s)-1]
+}