WIP rewrite the daemon

cmd subdir does not build on purpose, it's only left in tree to grab old
code and move it to github.com/zrepl/zrepl/daemon

daemon/serve/serve_stdinserver.go

@@ -0,0 +1,79 @@
+package serve
+
+import (
+	"github.com/problame/go-netssh"
+	"github.com/zrepl/zrepl/config"
+	"github.com/zrepl/zrepl/daemon/nethelpers"
+	"io"
+	"net"
+	"path"
+	"time"
+)
+
+type StdinserverListenerFactory struct {
+	ClientIdentity string
+	sockpath       string
+}
+
+func StdinserverListenerFactoryFromConfig(g config.Global, in *config.StdinserverServer) (f *StdinserverListenerFactory, err error) {
+
+	f = &StdinserverListenerFactory{
+		ClientIdentity: in.ClientIdentity,
+	}
+
+	f.sockpath = path.Join(g.Serve.StdinServer.SockDir, f.ClientIdentity)
+
+	return
+}
+
+func (f *StdinserverListenerFactory) Listen() (net.Listener, error) {
+
+	if err := nethelpers.PreparePrivateSockpath(f.sockpath); err != nil {
+		return nil, err
+	}
+
+	l, err := netssh.Listen(f.sockpath)
+	if err != nil {
+		return nil, err
+	}
+	return StdinserverListener{l}, nil
+}
+
+type StdinserverListener struct {
+	l *netssh.Listener
+}
+
+func (l StdinserverListener) Addr() net.Addr {
+	return netsshAddr{}
+}
+
+func (l StdinserverListener) Accept() (net.Conn, error) {
+	c, err := l.l.Accept()
+	if err != nil {
+		return nil, err
+	}
+	return netsshConnToNetConnAdatper{c}, nil
+}
+
+func (l StdinserverListener) Close() (err error) {
+	return l.l.Close()
+}
+
+type netsshAddr struct{}
+
+func (netsshAddr) Network() string { return "netssh" }
+func (netsshAddr) String() string  { return "???" }
+
+type netsshConnToNetConnAdatper struct {
+	io.ReadWriteCloser // works for both netssh.SSHConn and netssh.ServeConn
+}
+
+func (netsshConnToNetConnAdatper) LocalAddr() net.Addr { return netsshAddr{} }
+
+func (netsshConnToNetConnAdatper) RemoteAddr() net.Addr { return netsshAddr{} }
+
+func (netsshConnToNetConnAdatper) SetDeadline(t time.Time) error { return nil }
+
+func (netsshConnToNetConnAdatper) SetReadDeadline(t time.Time) error { return nil }
+
+func (netsshConnToNetConnAdatper) SetWriteDeadline(t time.Time) error { return nil }