feat(nix-daemon): Implement client handler. r/8907

This change includes only the basic nix handshake protocol handling and
sets up a client session. The only supported operation at this point is
SetOptions.

Additional operations will be implemented in subsequent cls.

Change-Id: I3eccd9e0ceb270c3865929543c702f1491768852
Reviewed-on: https://cl.tvl.fyi/c/depot/+/12743
Autosubmit: Vladimir Kryachko <v.kryachko@gmail.com>
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
Reviewed-by: edef <edef@edef.eu>
Reviewed-by: Brian Olsen <me@griff.name>

1 files changed, 10 insertions, 0 deletions

diff --git a/tvix/nix-compat/src/wire/ser/mod.rs b/tvix/nix-compat/src/wire/ser/mod.rs
index 5860226f39eb..ef3c6e2e372f 100644
--- a/tvix/nix-compat/src/wire/ser/mod.rs
+++ b/tvix/nix-compat/src/wire/ser/mod.rs
@@ -122,3 +122,13 @@ pub trait NixSerialize {
     where
         W: NixWrite;
 }
+
+// Noop
+impl NixSerialize for () {
+    async fn serialize<W>(&self, _writer: &mut W) -> Result<(), W::Error>
+    where
+        W: NixWrite,
+    {
+        Ok(())
+    }
+}