(* simple-rpc.sml * * COPYRIGHT (c) 1997 AT&T Labs Research. * * Generators for simple RPC protocols. *) structure SimpleRPC : SIMPLE_RPC = struct type 'a event = 'a CML.event fun call reqMB arg = let val replV = SyncVar.iVar() in Mailbox.send(reqMB, (arg, replV)); SyncVar.iGet replV end fun mkRPC f = let val reqMB = Mailbox.mailbox() val entryEvt = CML.wrap ( Mailbox.recvEvt reqMB, fn (arg, replV) => SyncVar.iPut(replV, f arg)) in { call = call reqMB, entryEvt = entryEvt } end fun mkRPC_In f = let val reqMB = Mailbox.mailbox() val reqEvt = Mailbox.recvEvt reqMB fun entryEvt state = CML.wrap ( reqEvt, fn (arg, replV) => SyncVar.iPut(replV, f(arg, state))) in { call = call reqMB, entryEvt = entryEvt } end fun mkRPC_Out f = let val reqMB = Mailbox.mailbox() val reqEvt = Mailbox.recvEvt reqMB val entryEvt = CML.wrap ( reqEvt, fn (arg, replV) => let val (res, state') = f arg in SyncVar.iPut(replV, res); state' end) in { call = call reqMB, entryEvt = entryEvt } end fun mkRPC_InOut f = let val reqMB = Mailbox.mailbox() val reqEvt = Mailbox.recvEvt reqMB fun entryEvt state = CML.wrap ( reqEvt, fn (arg, replV) => let val (res, state') = f(arg, state) in SyncVar.iPut(replV, res); state' end) in { call = call reqMB, entryEvt = entryEvt } end end
