Initial QSfera import

Server/vendor/github.com/RoaringBitmap/roaring/v2/serialization.go

@@ -0,0 +1,18 @@
+package roaring
+
+import (
+	"encoding/binary"
+	"io"
+)
+
+// writeTo for runContainer16 follows this
+// spec: https://github.com/RoaringBitmap/RoaringFormatSpec
+func (b *runContainer16) writeTo(stream io.Writer) (int, error) {
+	buf := make([]byte, 2+4*len(b.iv))
+	binary.LittleEndian.PutUint16(buf[0:], uint16(len(b.iv)))
+	for i, v := range b.iv {
+		binary.LittleEndian.PutUint16(buf[2+i*4:], v.start)
+		binary.LittleEndian.PutUint16(buf[2+2+i*4:], v.length)
+	}
+	return stream.Write(buf)
+}