Initial project import

tools/v/vlib/io/readerwriter.v

@@ -0,0 +1,37 @@
+module io
+
+// ReaderWriter represents a stream that can be read and written.
+pub interface ReaderWriter {
+	Reader
+	Writer
+}
+
+// ReaderWriterImpl is a ReaderWriter that can be made from
+// a separate reader and writer (see fn make_readerwriter).
+struct ReaderWriterImpl {
+mut:
+	r Reader
+	w Writer
+}
+
+// read reads up to `buf.len` bytes into `buf`. It returns
+// the number of bytes read or any error encountered.
+pub fn (mut r ReaderWriterImpl) read(mut buf []u8) !int {
+	return r.r.read(mut buf)
+}
+
+// write writes `buf.len` bytes from `buf` to the underlying
+// data stream. It returns the number of bytes written or any error
+// encountered.
+pub fn (mut r ReaderWriterImpl) write(buf []u8) !int {
+	return r.w.write(buf)
+}
+
+// make_readerwriter takes a rstream and a wstream and makes
+// an rwstream with them.
+pub fn make_readerwriter(r Reader, w Writer) ReaderWriterImpl {
+	return ReaderWriterImpl{
+		r: r
+		w: w
+	}
+}