btrfsitem: Add `Free` and `CloneItem` methods to Items

1 files changed, 35 insertions, 0 deletions

diff --git a/lib/containers/slicepool.go b/lib/containers/slicepool.go
new file mode 100644
index 0000000..861691a
--- /dev/null
+++ b/lib/containers/slicepool.go
@@ -0,0 +1,35 @@
+// Copyright (C) 2023  Luke Shumaker <lukeshu@lukeshu.com>
+//
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+package containers
+
+import (
+	"git.lukeshu.com/go/typedsync"
+)
+
+type SlicePool[T any] struct {
+	// TODO(lukeshu): Consider bucketing slices by size, to
+	// increase odds that the `cap(ret) >= size` check passes.
+	inner typedsync.Pool[[]T]
+}
+
+func (p *SlicePool[T]) Get(size int) []T {
+	if size == 0 {
+		return nil
+	}
+	ret, ok := p.inner.Get()
+	if ok && cap(ret) >= size {
+		ret = ret[:size]
+	} else {
+		ret = make([]T, size)
+	}
+	return ret
+}
+
+func (p *SlicePool[T]) Put(slice []T) {
+	if slice == nil {
+		return
+	}
+	p.inner.Put(slice)
+}