s1ap_proxy: add types for S1AP PDU and IE tuples

Change-Id: I39e0a12aade5e31c414cb639dbf333af2a5b7be4
---
M src/s1ap_proxy.erl
1 file changed, 13 insertions(+), 4 deletions(-)


git pull ssh://gerrit.osmocom.org:29418/erlang/osmo-s1gw refs/changes/95/38295/1

diff --git a/src/s1ap_proxy.erl b/src/s1ap_proxy.erl
index c985601..c386f29 100644
--- a/src/s1ap_proxy.erl
+++ b/src/s1ap_proxy.erl
@@ -50,6 +50,12 @@
 -include("S1AP-IEs.hrl").
 
 
+-type s1ap_pdu() :: {initiatingMessage, #'InitiatingMessage'{}} |
+                    {successfulOutcome, #'SuccessfulOutcome'{}} |
+                    {unsuccessfulOutcome, #'UnsuccessfulOutcome'{}}.
+-type s1ap_ie() :: #'ProtocolIE-Field'{}.
+-type s1ap_ie_val() :: tuple().
+
 -type mme_ue_id() :: 0..16#ffffffff.
 -type enb_ue_id() :: 0..16#ffffff.
 -type erab_id() :: 0..16#ff.
@@ -102,14 +108,14 @@
 %% ------------------------------------------------------------------
 
 %% Encode an S1AP PDU
--spec encode_pdu(tuple()) -> {ok, binary()} |
-                             {error, {asn1, tuple()}}.
+-spec encode_pdu(s1ap_pdu()) -> {ok, binary()} |
+                                {error, {asn1, tuple()}}.
 encode_pdu(Pdu) ->
     'S1AP-PDU-Descriptions':encode('S1AP-PDU', Pdu).
 
 
 %% Decode an S1AP PDU
--spec decode_pdu(binary()) -> {ok, tuple()} |
+-spec decode_pdu(binary()) -> {ok, s1ap_pdu()} |
                               {error, {asn1, tuple()}}.
 decode_pdu(Data) ->
     'S1AP-PDU-Descriptions':decode('S1AP-PDU', Data).
@@ -118,6 +124,7 @@
 %% Helper function for handle_pdu/3.
 %% Attempt to encode a new (modified) S1AP PDU,
 %% return a new binary() on success or Data on error.
+-spec handle_pdu_new(binary(), s1ap_pdu(), proxy_state()) -> {binary(), proxy_state()}.
 handle_pdu_new(Data, NewPdu, S) ->
     case encode_pdu(NewPdu) of
         {ok, NewData} ->
@@ -128,6 +135,8 @@
     end.
 
 
+-spec handle_pdu(binary(), s1ap_pdu(), proxy_state()) -> {binary(), proxy_state()}.
+
 %% 9.1.3.1 E-RAB SETUP REQUEST
 handle_pdu(Data, {Outcome = initiatingMessage,
                   #'InitiatingMessage'{procedureCode = ?'id-E-RABSetup',
@@ -216,7 +225,7 @@
 
 
 %% Handle a single IE (Information Element)
--spec handle_ie(tuple(), proxy_state()) -> {tuple(), proxy_state()}.
+-spec handle_ie(s1ap_ie(), proxy_state()) -> {s1ap_ie_val(), proxy_state()}.
 
 %% E-RAB SETUP REQUEST related IEs
 handle_ie(#'ProtocolIE-Field'{id = ?'id-E-RABToBeSetupListBearerSUReq',

