From 026d0c8ae56953a3d375c5d7afd43b0ff8211bc9 Mon Sep 17 00:00:00 2001
From: pacien <pacien.trangirard@pacien.net>
Date: Sun, 16 Sep 2018 15:19:29 +0200
Subject: [PATCH] exim: parametrise package

This allows the definition of a custom derivation of Exim,
which can be used to enable custom features such as LDAP and PAM support.

The default behaviour remains unchanged (defaulting to pkgs.exim).

(cherry picked from commit d73ed4264f48da098e782c0e204ae4ce613801e5)
---
 nixos/modules/services/mail/exim.nix | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/nixos/modules/services/mail/exim.nix b/nixos/modules/services/mail/exim.nix
index 06c4b2811b3f..c05811291359 100644
--- a/nixos/modules/services/mail/exim.nix
+++ b/nixos/modules/services/mail/exim.nix
@@ -2,7 +2,7 @@
 
 let
   inherit (lib) mkIf mkOption singleton types;
-  inherit (pkgs) coreutils exim;
+  inherit (pkgs) coreutils;
   cfg = config.services.exim;
 in
 
@@ -57,6 +57,16 @@ in
         '';
       };
 
+      package = mkOption {
+        type = types.package;
+        default = pkgs.exim;
+        defaultText = "pkgs.exim";
+        description = ''
+          The Exim derivation to use.
+          This can be used to enable features such as LDAP or PAM support.
+        '';
+      };
+
     };
 
   };
@@ -74,7 +84,7 @@ in
         spool_directory = ${cfg.spoolDir}
         ${cfg.config}
       '';
-      systemPackages = [ exim ];
+      systemPackages = [ cfg.package ];
     };
 
     users.users = singleton {
@@ -89,14 +99,14 @@ in
       gid = config.ids.gids.exim;
     };
 
-    security.wrappers.exim.source = "${exim}/bin/exim";
+    security.wrappers.exim.source = "${cfg.package}/bin/exim";
 
     systemd.services.exim = {
       description = "Exim Mail Daemon";
       wantedBy = [ "multi-user.target" ];
       restartTriggers = [ config.environment.etc."exim.conf".source ];
       serviceConfig = {
-        ExecStart   = "${exim}/bin/exim -bdf -q30m";
+        ExecStart   = "${cfg.package}/bin/exim -bdf -q30m";
         ExecReload  = "${coreutils}/bin/kill -HUP $MAINPID";
       };
       preStart = ''