cmd: allow import/running ctrld as library

cmd/cli/conn.go

@@ -0,0 +1,51 @@
+package cli
+
+import (
+	"net"
+	"time"
+)
+
+// logConn wraps a net.Conn, override the Write behavior.
+// runCmd uses this wrapper, so as long as startCmd finished,
+// ctrld log won't be flushed with un-necessary write errors.
+type logConn struct {
+	conn net.Conn
+}
+
+func (lc *logConn) Read(b []byte) (n int, err error) {
+	return lc.conn.Read(b)
+}
+
+func (lc *logConn) Close() error {
+	return lc.conn.Close()
+}
+
+func (lc *logConn) LocalAddr() net.Addr {
+	return lc.conn.LocalAddr()
+}
+
+func (lc *logConn) RemoteAddr() net.Addr {
+	return lc.conn.RemoteAddr()
+}
+
+func (lc *logConn) SetDeadline(t time.Time) error {
+	return lc.conn.SetDeadline(t)
+}
+
+func (lc *logConn) SetReadDeadline(t time.Time) error {
+	return lc.conn.SetReadDeadline(t)
+}
+
+func (lc *logConn) SetWriteDeadline(t time.Time) error {
+	return lc.conn.SetWriteDeadline(t)
+}
+
+func (lc *logConn) Write(b []byte) (int, error) {
+	// Write performs writes with underlying net.Conn, ignore any errors happen.
+	// "ctrld run" command use this wrapper to report errors to "ctrld start".
+	// If no error occurred, "ctrld start" may finish before "ctrld run" attempt
+	// to close the connection, so ignore errors conservatively here, prevent
+	// un-necessary error "write to closed connection" flushed to ctrld log.
+	_, _ = lc.conn.Write(b)
+	return len(b), nil
+}