Merge pull request #52753 from munnerz/sample-controller

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

sample-controller: add example CRD controller

**What this PR does / why we need it**:

Adds a sample-controller example repository

fixes #52752

**Special notes for your reviewer**:

This is currently based on the sttts:sttts-codegen-scripts branch and should not be merged until that is (ref https://github.com/kubernetes/kubernetes/pull/52186)

**Release note**:

```
Add sample-controller repository
```

/cc @sttts @nikhita @colemickens

Kubernetes-commit: 9a7800f7d2efb88b397674672ac56f898826cf7c

vendor/github.com/json-iterator/go/feature_pool.go

@@ -0,0 +1,57 @@
+package jsoniter
+
+import (
+	"io"
+)
+
+// IteratorPool a thread safe pool of iterators with same configuration
+type IteratorPool interface {
+	BorrowIterator(data []byte) *Iterator
+	ReturnIterator(iter *Iterator)
+}
+
+// StreamPool a thread safe pool of streams with same configuration
+type StreamPool interface {
+	BorrowStream(writer io.Writer) *Stream
+	ReturnStream(stream *Stream)
+}
+
+func (cfg *frozenConfig) BorrowStream(writer io.Writer) *Stream {
+	select {
+	case stream := <-cfg.streamPool:
+		stream.Reset(writer)
+		return stream
+	default:
+		return NewStream(cfg, writer, 512)
+	}
+}
+
+func (cfg *frozenConfig) ReturnStream(stream *Stream) {
+	stream.Error = nil
+	select {
+	case cfg.streamPool <- stream:
+		return
+	default:
+		return
+	}
+}
+
+func (cfg *frozenConfig) BorrowIterator(data []byte) *Iterator {
+	select {
+	case iter := <-cfg.iteratorPool:
+		iter.ResetBytes(data)
+		return iter
+	default:
+		return ParseBytes(cfg, data)
+	}
+}
+
+func (cfg *frozenConfig) ReturnIterator(iter *Iterator) {
+	iter.Error = nil
+	select {
+	case cfg.iteratorPool <- iter:
+		return
+	default:
+		return
+	}
+}