happy-eyeballs: timer always returns an 'action list'

happy-eyeballs-lwt.opam

@@ -8,7 +8,7 @@ doc: "https://roburio.github.io/happy-eyeballs/"
 license: "ISC"
 
 depends: [
-  "ocaml" {>= "4.10.0"}
+  "ocaml" {>= "4.08.0"}
   "dune" {>= "2.0.0"}
   "happy-eyeballs" {=version}
   "cmdliner"

happy-eyeballs-mirage.opam

@@ -8,7 +8,7 @@ doc: "https://roburio.github.io/happy-eyeballs/"
 license: "ISC"
 
 depends: [
-  "ocaml" {>= "4.10.0"}
+  "ocaml" {>= "4.08.0"}
   "dune" {>= "2.0.0"}
   "happy-eyeballs" {=version}
   "duration"

happy-eyeballs.opam

@@ -8,7 +8,7 @@ doc: "https://roburio.github.io/happy-eyeballs/"
 license: "ISC"
 
 depends: [
-  "ocaml" {>= "4.10.0"}
+  "ocaml" {>= "4.08.0"}
   "dune" {>= "2.0.0"}
   "duration"
   "domain-name" {>= "0.2.0"}

lwt/happy_eyeballs_lwt.ml

@@ -104,13 +104,13 @@ let handle_timer_actions t actions =
 let rec timer t =
   let open Lwt.Infix in
   let rec loop () =
-    let he, actions = Happy_eyeballs.timer t.he (now ()) in
+    let he, cont, actions = Happy_eyeballs.timer t.he (now ()) in
     t.he <- he ;
-    match actions with
+    handle_timer_actions t actions ;
+    match cont with
     | `Suspend ->
       timer t
-    | `Act actions ->
-      handle_timer_actions t actions ;
+    | `Act ->
       Lwt_unix.sleep t.timer_interval >>= fun () ->
       loop ()
   in

mirage/happy_eyeballs_mirage.ml

@@ -88,13 +88,13 @@ module Make (R : Mirage_random.S) (T : Mirage_time.S) (C : Mirage_clock.MCLOCK)
   let rec timer t =
     let open Lwt.Infix in
     let rec loop () =
-      let he, actions = Happy_eyeballs.timer t.he (C.elapsed_ns ()) in
+      let he, cont, actions = Happy_eyeballs.timer t.he (C.elapsed_ns ()) in
       t.he <- he ;
-      match actions with
+      handle_timer_actions t actions ;
+      match cont with
       | `Suspend ->
         timer t
-      | `Act actions ->
-        handle_timer_actions t actions ;
+      | `Act ->
         T.sleep_ns t.timer_interval >>= fun () ->
         loop ()
     in

src/happy_eyeballs.ml

@@ -137,7 +137,7 @@ let add_conn host id conn c =
     c
 
 let expand_list ips ports =
-  List.concat_map (fun ip -> List.map (fun p -> (ip, p)) ports) ips
+  List.flatten (List.map (fun ip -> List.map (fun p -> (ip, p)) ports) ips)
 
 (* all input has been verified that ips and ports are non-empty. *)
 let expand_list_split ips ports =
@@ -181,10 +181,8 @@ let timer t now =
   in
   Log.debug (fun m -> m "timer %d actions" (List.length actions));
   { t with conns },
-  if Domain_name.Host_map.is_empty conns then
-    (assert (actions = []); `Suspend)
-  else
-    `Act actions
+  (if Domain_name.Host_map.is_empty conns then `Suspend else `Act),
+  actions
 
 let connect t now ~id host ports =
   if ports = [] then failwith "empty port list not supported";

src/happy_eyeballs.mli

@@ -32,11 +32,12 @@ val create : ?aaaa_timeout:int64 -> ?connect_timeout:int64 ->
     [connect_timeout] and [resolve_timeout] use a default of
     [Duration.of_sec 1]. *)
 
-val timer : t -> int64 -> t * [ `Suspend | `Act of action list ]
+val timer : t -> int64 -> t * [ `Suspend | `Act ] * action list
 (** [timer t ts] is a timer function that results in an updated [t] and either
-    [`Suspend] signalling the timer thread can sleep or [`Act actions] a list
-    of actions that need to be performed (connection to be retried, connection
-    failures to be reported, ...).
+    [`Suspend] signalling the timer thread can sleep or [`Act] that the timer
+    should be called again. In addition, a list of actions that need to be
+    performed (connection to be retried, connection failures to be reported,
+    ...) is provided.
     The timer thread should be signalled to resume after calling [connect] or
     [connect_ip]. *)