From 780ea64fff1bae552510ed419ec2bb011923a5cc Mon Sep 17 00:00:00 2001 From: Anders Svensson Date: Sun, 21 Jun 2015 09:55:17 +0200 Subject: Fix start order of alternate transports A transport configured with diameter:add_transport/2 can be passed multiple transport_module/transport_config tuples in order to specify alternate configuration, modules being attempted in order until one succeeds. This is primarily for the connecting case, to allow a transport to be configured to first attempt connection over SCTP, and then TCP in case SCTP fails, with configuration like that documented: {transport_module, diameter_sctp}, {transport_config, [...], 5000}, {transport_module, diameter_tcp}, {transport_config, [...]} If the options are the same in both cases, another possibility would be configuration like this, which attaches the same transport_config to both modules: {transport_module, diameter_sctp}, {transport_module, diameter_tcp}, {transport_config, [...], 5000}, However, in this case the start order was reversed relative to the documented order: first tcp, then sctp. This commit restores the intended order. --- lib/diameter/src/base/diameter_peer.erl | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/lib/diameter/src/base/diameter_peer.erl b/lib/diameter/src/base/diameter_peer.erl index 89b63c8a92..a814e52f29 100644 --- a/lib/diameter/src/base/diameter_peer.erl +++ b/lib/diameter/src/base/diameter_peer.erl @@ -121,7 +121,7 @@ pair([{transport_module, M} | Rest], Mods, Acc) -> pair([{transport_config = T, C} | Rest], Mods, Acc) -> pair([{T, C, ?DEFAULT_TTMO} | Rest], Mods, Acc); pair([{transport_config, C, Tmo} | Rest], Mods, Acc) -> - pair(Rest, [], acc({Mods, C, Tmo}, Acc)); + pair(Rest, [], acc({lists:reverse(Mods), C, Tmo}, Acc)); pair([_ | Rest], Mods, Acc) -> pair(Rest, Mods, Acc); @@ -130,13 +130,16 @@ pair([_ | Rest], Mods, Acc) -> pair([], [], []) -> [{[?DEFAULT_TMOD], ?DEFAULT_TCFG, ?DEFAULT_TTMO}]; -%% One transport_module, one transport_config. -pair([], [M], [{[], Cfg, Tmo}]) -> - [{[M], Cfg, Tmo}]; +%% One transport_module, one transport_config: ignore option order. +%% That is, interpret [{transport_config, _}, {transport_module, _}] +%% as if the order was reversed, not as config with default module and +%% module with default config. +pair([], [_] = Mods, [{[], Cfg, Tmo}]) -> + [{Mods, Cfg, Tmo}]; %% Trailing transport_module: default transport_config. pair([], [_|_] = Mods, Acc) -> - lists:reverse(acc({Mods, ?DEFAULT_TCFG, ?DEFAULT_TTMO}, Acc)); + pair([{transport_config, ?DEFAULT_TCFG}], Mods, Acc); pair([], [], Acc) -> lists:reverse(def(Acc)). -- cgit v1.2.3