[socket-nif] Add (partial) support for socket (level sctp) option associnfo

Added support for the SCTP option ASSOCINFO.

This option is a bit tricky. As the underlying structure (sctp_assocparams)
contains the assoc_id, it begs the question what happens if this option
is fetched for:

   * The own assoc (which means that we might have the assoc id in the
     descriptor and can initiate that part of the struct accordningly).
   * Another assoc: From assoc A asks for info with assoc_id set to
     that of assoc B.
   * The "owning" endpoint.
   * Another endpoint (an endpoint to which the assoc does not belong).

So, if the user calls socket:[getopt|setopt] for an association socket,
shall we require that the assoc_id field is set to -1? Or not set at all
and therefor filled in automatically by the nif-code?

And, if the user calls socket:[getopt|setopt] for an endpoint socket,
shall we require that the assoc_id field is set to a valid id? Or shall
it not be allowed?

Questions, questions...

OTP-14831

1 files changed, 1 insertions, 0 deletions

diff --git a/erts/emulator/nifs/common/socket_int.h b/erts/emulator/nifs/common/socket_int.h
index 67e4baba27..28f42a7345 100644
--- a/erts/emulator/nifs/common/socket_int.h
+++ b/erts/emulator/nifs/common/socket_int.h
@@ -167,6 +167,7 @@ extern ERL_NIF_TERM esock_atom_einval;
 #define MKT8(E,E1,E2,E3,E4,E5,E6,E7,E8) \
     enif_make_tuple8((E), (E1), (E2), (E3), (E4), (E5), (E6), (E7), (E8))
 #define MKTA(E, A, AL)      enif_make_tuple_from_array((E), (A), (AL))
+#define MKUI(E,I)           enif_make_uint((E), (I))
 
 #define MCREATE(N)          enif_mutex_create((N))
 #define MDESTROY(M)         enif_mutex_destroy((M))