Add base for faketls

wrappers/stream/buffered_reader.go

@@ -0,0 +1,43 @@
+package stream
+
+import (
+	"bytes"
+	"time"
+)
+
+type bufferedReaderReadFunc func() ([]byte, error)
+
+type bufferedReader struct {
+	buf      bytes.Buffer
+	readFunc bufferedReaderReadFunc
+}
+
+func (b *bufferedReader) Read(p []byte) (int, error) {
+	if b.buf.Len() > 0 {
+		return b.flush(p)
+	}
+
+	res, err := b.readFunc()
+	if err != nil {
+		return 0, err
+	}
+	b.buf.Write(res)
+
+	return b.flush(p)
+}
+
+func (b *bufferedReader) ReadTimeout(p []byte, _ time.Duration) (int, error) {
+	return b.Read(p)
+}
+
+func (b *bufferedReader) flush(p []byte) (int, error) {
+	if b.buf.Len() > len(p) {
+		return b.buf.Read(p)
+	}
+
+	sizeToReturn := b.buf.Len()
+	copy(p, b.buf.Bytes())
+	b.buf.Reset()
+
+	return sizeToReturn, nil
+}