Expose uv_clock_gettime

src/c/luv_c_function_descriptions.ml

@@ -1852,6 +1852,10 @@ struct
     let hrtime =
       foreign "uv_hrtime"
         (void @-> returning uint64_t)
+
+    let clock_gettime =
+      foreign "uv_clock_gettime"
+        (int @-> ptr Types.Time.Timespec.t @-> returning error_code)
   end
 
   module Random =

src/c/luv_c_type_descriptions.ml

@@ -976,6 +976,18 @@ struct
       let usec = field t "tv_usec" int32_t
       let () = seal t
     end
+
+    module Timespec =
+    struct
+      let t : ([ `Timespec ] structure) typ =
+        typedef (structure "`Timespec64") "uv_timespec64_t"
+      let sec = field t "tv_sec" int64_t
+      let nsec = field t "tv_nsec" int32_t
+      let () = seal t
+
+      let monotonic = constant "UV_CLOCK_MONOTONIC" int
+      let real_time = constant "UV_CLOCK_REALTIME" int
+    end
   end
 
   module Env_item =

src/c/shims.h

@@ -714,4 +714,14 @@
     static void uv_os_free_group(uv_passwd_t *group)
     {
     }
+
+    typedef struct {
+        int64_t tv_sec;
+        int32_t tv_nsec;
+    } uv_timespec64_t;
+
+    static int uv_clock_gettime(int clock_id, uv_timespec64_t *time)
+    {
+        return ENOSYS;
+    }
 #endif

src/feature/detect_features.ml

@@ -230,6 +230,7 @@ let () =
 
   let parallelism = "available_parallelism" in
   needs 44 parallelism "See {!Luv.System_info.available_parallelism}.";
+  needs 45 "clock_gettime" "See {!Luv.Time.clock_gettime}.";
   needs 45 "cpumask_size" "See {!Luv.System_info.cpumask_size}.";
   needs  9 "disconnect" "See [`DISCONNECT] in {!Luv.Poll.Event.t}.";
   needs 21 "eftype" "See [`EFTYPE] in {!Luv.Error.t}.";

src/time.ml

@@ -3,11 +3,13 @@
 
 
 
-type t = {
+type timeval = {
   tv_sec : int64;
   tv_usec : int32;
 }
 
+type t = timeval
+
 let gettimeofday () =
   let timeval = Ctypes.make C.Types.Time.Timeval.t in
   C.Functions.Time.gettimeofday (Ctypes.addr timeval)
@@ -21,5 +23,25 @@ let gettimeofday () =
 let hrtime =
   C.Functions.Time.hrtime
 
+type timespec = {
+  sec : int64;
+  nsec : int32;
+}
+
+let clock_gettime clock =
+  let timespec = Ctypes.make C.Types.Time.Timespec.t in
+  let clock =
+    match clock with
+    | `Monotonic -> C.Types.Time.Timespec.monotonic
+    | `Real_time -> C.Types.Time.Timespec.real_time
+  in
+  C.Functions.Time.clock_gettime clock (Ctypes.addr timespec)
+  |> Error.to_result_lazy begin fun () ->
+    {
+      sec = Ctypes.getf timespec C.Types.Time.Timespec.sec;
+      nsec = Ctypes.getf timespec C.Types.Time.Timespec.nsec;
+    }
+  end
+
 let sleep =
   C.Blocking.Time.sleep

src/time.mli

@@ -3,14 +3,18 @@
 
 
 
-type t = {
+type timeval = {
   tv_sec : int64;
   tv_usec : int32;
 }
 (** Binds {{:http://docs.libuv.org/en/v1.x/misc.html#c.uv_timeval64_t}
     [uv_timeval64_t]}. *)
 
-val gettimeofday : unit -> (t, Error.t) result
+(**/**)
+type t = timeval
+(**/**)
+
+val gettimeofday : unit -> (timeval, Error.t) result
 (** Binds {{:http://docs.libuv.org/en/v1.x/misc.html#c.uv_gettimeofday}
     [uv_gettimeofday]}. See
     {{:http://man7.org/linux/man-pages/man3/gettimeofday.3p.html}
@@ -28,6 +32,25 @@ val hrtime : unit -> Unsigned.uint64
     {{:http://man7.org/linux/man-pages/man3/clock_gettime.3p.html}
     [clock_gettime(3p)]}. *)
 
+type timespec = {
+  sec : int64;
+  nsec : int32;
+}
+(** Binds {{:http://docs.libuv.org/en/v1.x/misc.html#c.uv_timespec64_t}
+    [uv_timespec64_t]}. *)
+
+val clock_gettime : [< `Monotonic | `Real_time ] -> (timespec, Error.t) result
+(** Samples one of the high-resolution timers.
+
+    Binds {{:http://docs.libuv.org/en/v1.x/misc.html#c.uv_clock_gettime}
+    [uv_clock_gettime]}. See
+    {{:http://man7.org/linux/man-pages/man3/clock_gettime.3p.html}
+    [clock_gettime(3p)]}.
+
+    Requires Luv 0.5.13 and libuv 1.45.0.
+
+    {{!Luv.Require} Feature check}: [Luv.Require.(has clock_gettime)] *)
+
 val sleep : int -> unit
 (** Suspends the calling thread for at least the given number of milliseconds.