implement ifwait trigger service and use in bridge

should we convert all ifwait uses to this trigger too? seems
reasonable

modules/bridge/default.nix

@@ -14,6 +14,8 @@ let
   inherit (pkgs) liminix;
 in
 {
+  imports = [ ../ifwait ];
+
   options = {
     system.service.bridge = {
       primary = mkOption { type = liminix.lib.types.serviceDefn; };
@@ -27,7 +29,7 @@ in
         description = "bridge interface name to create";
       };
     };
-    members = liminix.callService ./members.nix {
+    members = config.system.callService ./members.nix {
       primary = mkOption {
         type = liminix.lib.types.interface;
         description = "primary bridge interface";
@@ -47,5 +49,5 @@ in
     # a better way to test for the existence of vlan config:
     # maybe the module should set an `enabled` attribute?
     BRIDGE_VLAN_FILTERING = "y";
-  };    
+  };
 }

modules/bridge/members.nix

@@ -2,6 +2,7 @@
   liminix
 , ifwait
 , lib
+, svc
 }:
 { members, primary } :
 
@@ -10,14 +11,20 @@ let
   inherit (liminix.services) bundle oneshot;
   inherit (lib) mkOption types;
   addif = member :
-    oneshot {
-      name = "${primary.name}.member.${member.name}";
-      up = ''
-        dev=$(output ${member} ifname)
-        ${ifwait}/bin/ifwait $dev running && ip link set dev $dev master $(output ${primary} ifname)
-      '';
-      down = "ip link set dev $(output ${member} ifname) nomaster";
+    # how do we get sight of services from here? maybe we need to
+    # implement ifwait as a regualr derivation instead of a
+    # servicedefinition
+    svc.ifwait.build {
+      state = "running";
+      interface = member;
       dependencies = [ primary member ];
+      service = oneshot {
+        name = "${primary.name}.member.${member.name}";
+        up = ''
+          ip link set dev $(output ${member} ifname) master $(output ${primary} ifname)
+        '';
+        down = "ip link set dev $(output ${member} ifname) nomaster";
+      };
     };
 in bundle {
   name = "${primary.name}.members";

modules/ifwait/default.nix

@@ -0,0 +1,18 @@
+{ config, pkgs, lib, ... } :
+let
+  inherit (pkgs) liminix;
+  inherit (lib) mkOption types;
+in {
+  options.system.service.ifwait =
+    mkOption { type = liminix.lib.types.serviceDefn; };
+
+  config.system.service.ifwait = config.system.callService ./ifwait.nix {
+    state = mkOption { type = types.str; };
+    interface = mkOption {
+      type = liminix.lib.types.interface;
+    };
+    service = mkOption {
+      type = liminix.lib.types.service;
+    };
+  };
+}

modules/ifwait/ifwait.nix

@@ -0,0 +1,15 @@
+{ ifwait, liminix } :
+{
+  state
+, interface
+, service
+}:
+let
+  inherit (liminix.services) longrun;
+in longrun {
+  name = "ifwait.${interface.name}";
+  buildInputs = [ service ];
+  run = ''
+    ${ifwait}/bin/ifwait -s ${service.name}  $(output ${interface} ifname) ${state}
+  '';
+}

tests/updown/script.expect

@@ -13,9 +13,14 @@ spawn socat unix-connect:vm/console -
 set console_id $spawn_id
 
 expect "BusyBox" 
-expect "#" { send "PS1=RE\\ADY_\\ \r" }
-expect "READY_" { send "sleep 3\r" }
-expect "READY_" { send "ip link\r" }
+expect "#" { send "PS1=RE\\ADY_\\ ; stty -echo \r" }
+expect "READY_" { send "s6-rc -b -a list\r"  } ; # -b waits for s6-rc lock
+expect "READY_" { send "ls /sys/class/net/lan/master\r" }
+expect {
+  "No such file or directory" { }
+  timeout { exit 1 }
+}
+
 expect "READY_" { send "cat /sys/class/net/lan/operstate\r" }
 expect {
   "down" { }
@@ -24,6 +29,36 @@ expect {
 expect "READY_" { send "s6-rc -a -u change\r"  }
 expect {
   "unable to take locks" { exit 1 }
-  "READY_" { send "hostname\r" }
+  "READY_" { send "\r" }
 }
-expect "updown"
+
+set spawn_id $monitor_id
+send "\r"
+expect "(qemu)"
+send "set_link virtio-net-pci.1 on\n"
+expect "(qemu)"
+send "set_link virtio-net-pci.0 on\n"
+expect "(qemu)"
+set spawn_id $console_id
+
+expect "entered forwarding state"
+send "\r"
+expect "READY_" { send "cat /sys/class/net/lan/operstate\r" }
+expect {
+  "down" {  exit 1 }
+  "up" { }
+}
+
+expect "READY_" { send "cat /sys/class/net/lan/master/uevent\r" }
+expect {
+  "INTERFACE=int" { }
+  timeout { exit 1 }
+}
+
+expect "READY_" { send "s6-rc listall int.link.a.10.8.0.1.member.lan.link ; hostname\r"  }
+
+expect {
+  "updown"  {}
+  timeout { exit 1 }
+}
+