[socket-nif] Add preliminary support for sendmsg

Added function sendmsg/2,3,4. Actually worked on the first try.
Something must be wrong...

Still no supported cmsghdr's (only support headers where the
data part is already a binary, which therefor does not require
any processing). So if the cmsghdrs actually work is unclear.

OTP-14831

1 files changed, 10 insertions, 0 deletions

diff --git a/lib/kernel/test/socket_server.erl b/lib/kernel/test/socket_server.erl
index f252be1683..34f354be32 100644
--- a/lib/kernel/test/socket_server.erl
+++ b/lib/kernel/test/socket_server.erl
@@ -900,8 +900,18 @@ peek_recvfrom(Sock, BufSz) ->
     end.
 
 
+send(#handler{socket = Sock, msg = true, type = stream}, Msg, _) ->
+    MsgHdr = #{iov => [Msg]},
+    socket:sendmsg(Sock, MsgHdr);
 send(#handler{socket = Sock, type = stream}, Msg, _) ->
     socket:send(Sock, Msg);
+send(#handler{socket = Sock, msg = true, type = dgram}, Msg, Dest) ->
+    MsgHdr = #{addr => Dest,
+               iov  => [Msg]},
+    %% ok = socket:setopt(Sock, otp, debug, true),
+    Res = socket:sendmsg(Sock, MsgHdr),
+    %% ok = socket:setopt(Sock, otp, debug, false),
+    Res;
 send(#handler{socket = Sock, type = dgram}, Msg, Dest) ->
     socket:sendto(Sock, Msg, Dest).