vms: move virtiofsd/waypipe into their own modules

pkgs/clan-cli/clan_cli/vms/waypipe.py

@@ -0,0 +1,50 @@
+import contextlib
+import socket
+import subprocess
+import time
+from collections.abc import Iterator
+
+from ..errors import ClanError
+from ..nix import nix_shell
+
+VMADDR_CID_HYPERVISOR = 2
+
+
+def test_vsock_port(port: int) -> bool:
+    try:
+        s = socket.socket(socket.AF_VSOCK, socket.SOCK_STREAM)
+        s.connect((VMADDR_CID_HYPERVISOR, port))
+        s.close()
+        return True
+    except OSError:
+        return False
+
+
+@contextlib.contextmanager
+def start_waypipe(cid: int | None, title_prefix: str) -> Iterator[None]:
+    if cid is None:
+        yield
+        return
+    waypipe = nix_shell(
+        ["git+https://git.clan.lol/clan/clan-core#waypipe"],
+        [
+            "waypipe",
+            "--vsock",
+            "--socket",
+            f"s{cid}:3049",
+            "--title-prefix",
+            title_prefix,
+            "client",
+        ],
+    )
+    with subprocess.Popen(waypipe) as proc:
+        try:
+            while not test_vsock_port(3049):
+                rc = proc.poll()
+                if rc is not None:
+                    msg = f"waypipe exited unexpectedly with code {rc}"
+                    raise ClanError(msg)
+                time.sleep(0.1)
+            yield
+        finally:
+            proc.kill()