From 3419aee8487840941124dbcfc24ddde12df49c63 Mon Sep 17 00:00:00 2001
From: Micael Karlberg <bmk@erlang.org>
Date: Fri, 12 Apr 2019 18:44:10 +0200
Subject: [socket] Update recvmsg to handle Timeout = nowait

Update function recvmsg and its spec(s) to handle
the Timeout value of nowait.
---
 erts/preloaded/ebin/socket.beam | Bin 72020 -> 72648 bytes
 erts/preloaded/src/socket.erl   |  42 +++++++++++++++++++++++++++++++++++++---
 2 files changed, 39 insertions(+), 3 deletions(-)

(limited to 'erts/preloaded')

diff --git a/erts/preloaded/ebin/socket.beam b/erts/preloaded/ebin/socket.beam
index d0e9817b8c..326fe49a69 100644
Binary files a/erts/preloaded/ebin/socket.beam and b/erts/preloaded/ebin/socket.beam differ
diff --git a/erts/preloaded/src/socket.erl b/erts/preloaded/src/socket.erl
index 3bd268403a..5b460ae81b 100644
--- a/erts/preloaded/src/socket.erl
+++ b/erts/preloaded/src/socket.erl
@@ -2043,6 +2043,14 @@ recvmsg(Socket) ->
       Socket  :: socket(),
       Flags   :: recv_flags(),
       MsgHdr  :: msghdr(),
+      Reason  :: term()
+                 ; (Socket, nowait) -> {ok, MsgHdr} |
+                                       {ok, SelInfo} |
+                                       {error, Reason} when
+      Socket  :: socket(),
+      MsgHdr  :: msghdr(),
+      SelInfo :: {select, RecvRef},
+      RecvRef :: reference(),
       Reason  :: term()
                  ; (Socket, Timeout) -> {ok, MsgHdr} | {error, Reason} when
       Socket  :: socket(),
@@ -2055,7 +2063,16 @@ recvmsg(Socket, Flags) when is_list(Flags) ->
 recvmsg(Socket, Timeout) ->
     recvmsg(Socket, 0, 0, ?SOCKET_RECV_FLAGS_DEFAULT, Timeout).
 
--spec recvmsg(Socket, Flags, Timeout) -> {ok, MsgHdr} | {error, Reason} when
+-spec recvmsg(Socket, Flags, nowait) -> {ok, MsgHdr} |
+                                        {ok, SelInfo} |
+                                        {error, Reason} when
+      Socket  :: socket(),
+      Flags   :: recv_flags(),
+      MsgHdr  :: msghdr(),
+      SelInfo :: {select, RecvRef},
+      RecvRef :: reference(),
+      Reason  :: term()
+                 ; (Socket, Flags, Timeout) -> {ok, MsgHdr} | {error, Reason} when
       Socket  :: socket(),
       Flags   :: recv_flags(),
       Timeout :: timeout(),
@@ -2077,7 +2094,20 @@ recvmsg(Socket, BufSz, CtrlSz) when is_integer(BufSz) andalso is_integer(CtrlSz)
 
 -spec recvmsg(Socket, 
               BufSz, CtrlSz,
-              Flags, Timeout) -> {ok, MsgHdr} | {error, Reason} when
+              Flags, nowait) -> {ok, MsgHdr} |
+                                {ok, SelInfo} |
+                                {error, Reason} when
+      Socket  :: socket(),
+      BufSz   :: non_neg_integer(),
+      CtrlSz  :: non_neg_integer(),
+      Flags   :: recv_flags(),
+      MsgHdr  :: msghdr(),
+      SelInfo :: {select, RecvRef},
+      RecvRef :: reference(),
+      Reason  :: term()
+                 ; (Socket, 
+                    BufSz, CtrlSz,
+                    Flags, Timeout) -> {ok, MsgHdr} | {error, Reason} when
       Socket  :: socket(),
       BufSz   :: non_neg_integer(),
       CtrlSz  :: non_neg_integer(),
@@ -2090,7 +2120,9 @@ recvmsg(#socket{ref = SockRef}, BufSz, CtrlSz, Flags, Timeout)
   when (is_integer(BufSz) andalso (BufSz >= 0)) andalso
        (is_integer(CtrlSz) andalso (CtrlSz >= 0)) andalso
        is_list(Flags) andalso
-       (is_integer(Timeout) orelse (Timeout =:= infinity)) ->
+       (is_integer(Timeout) orelse
+        (Timeout =:= infinity) orelse
+        (Timeout =:= nowait)) ->
     EFlags = enc_recv_flags(Flags),
     do_recvmsg(SockRef, BufSz, CtrlSz, EFlags, Timeout).
 
@@ -2101,6 +2133,10 @@ do_recvmsg(SockRef, BufSz, CtrlSz, EFlags, Timeout)  ->
         {ok, _MsgHdr} = OK ->
             OK;
 
+        {error, eagain} when (Timeout =:= nowait) ->
+            SelInfo = {select, RecvRef},
+            {ok, SelInfo};
+
         {error, eagain} ->
             %% There is nothing just now, but we will be notified when there
             %% is something to read (a select message).
-- 
cgit v1.2.3