From 41805ba1a2880003d3abe5fa3e59bcb40c377b88 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Edwin=20T=C3=B6r=C3=B6k?= <edwin.torok@cloud.com>
Date: Tue, 21 Nov 2023 15:39:40 +0000
Subject: [PATCH] CP-32622: Delay: replace select with time_limited_read
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Signed-off-by: Edwin Török <edwin.torok@cloud.com>
---
 dune-project                                           |  1 +
 ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/dune    |  1 +
 .../xapi-stdext/lib/xapi-stdext-threads/threadext.ml   | 10 +++++++---
 xapi-stdext-threads.opam                               |  1 +
 4 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/dune-project b/dune-project
index b412b0bfa94..1ae4affa93c 100644
--- a/dune-project
+++ b/dune-project
@@ -338,6 +338,7 @@
     (odoc :with-doc)
     (xapi-stdext-pervasives (= :version))
     (mtime :with-test)
+    (xapi-stdext-unix (= :version))
   )
 )
 
diff --git a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/dune b/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/dune
index a3b4d9f8609..4db49ea52e2 100644
--- a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/dune
+++ b/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/dune
@@ -5,6 +5,7 @@
   (libraries
     threads.posix
     unix
+    xapi-stdext-unix
     xapi-stdext-pervasives)
 )
 (test
diff --git a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.ml b/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.ml
index 56025d51154..ef30cfb5ba4 100644
--- a/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.ml
+++ b/ocaml/libs/xapi-stdext/lib/xapi-stdext-threads/threadext.ml
@@ -86,11 +86,15 @@ module Delay = struct
                 pipe_out
             )
           in
-          let r, _, _ = Unix.select [pipe_out] [] [] seconds in
+          let open Xapi_stdext_unix.Unixext in
           (* flush the single byte from the pipe *)
-          if r <> [] then ignore (Unix.read pipe_out (Bytes.create 1) 0 1) ;
+          try
+            let (_ : string) =
+              time_limited_single_read pipe_out 1 ~max_wait:seconds
+            in
+            false
+          with Timeout -> true
           (* return true if we waited the full length of time, false if we were woken *)
-          r = []
         with Pre_signalled -> false
       )
       (fun () ->
diff --git a/xapi-stdext-threads.opam b/xapi-stdext-threads.opam
index e6ad1798938..8de2f45c03e 100644
--- a/xapi-stdext-threads.opam
+++ b/xapi-stdext-threads.opam
@@ -14,6 +14,7 @@ depends: [
   "odoc" {with-doc}
   "xapi-stdext-pervasives" {= version}
   "mtime" {with-test}
+  "xapi-stdext-unix" {= version}
 ]
 build: [
   ["dune" "subst"] {dev}