mox!

moxio/atreader.go

@@ -0,0 +1,20 @@
+package moxio
+
+import (
+	"io"
+)
+
+// AtReader is turns an io.ReaderAt into a io.Reader by keeping track of the
+// offset.
+type AtReader struct {
+	R      io.ReaderAt
+	Offset int64
+}
+
+func (r *AtReader) Read(buf []byte) (int, error) {
+	n, err := r.R.ReadAt(buf, r.Offset)
+	if n > 0 {
+		r.Offset += int64(n)
+	}
+	return n, err
+}