uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

nixos/modules/services/mail/rss2email.nix

@@ -0,0 +1,135 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.rss2email;
+in {
+
+  ###### interface
+
+  options = {
+
+    services.rss2email = {
+
+      enable = mkOption {
+        type = types.bool;
+        default = false;
+        description = "Whether to enable rss2email.";
+      };
+
+      to = mkOption {
+        type = types.str;
+        description = "Mail address to which to send emails";
+      };
+
+      interval = mkOption {
+        type = types.str;
+        default = "12h";
+        description = "How often to check the feeds, in systemd interval format";
+      };
+
+      config = mkOption {
+        type = with types; attrsOf (oneOf [ str int bool ]);
+        default = {};
+        description = ''
+          The configuration to give rss2email.
+
+          Default will use system-wide <literal>sendmail</literal> to send the
+          email. This is rss2email's default when running
+          <literal>r2e new</literal>.
+
+          This set contains key-value associations that will be set in the
+          <literal>[DEFAULT]</literal> block along with the
+          <literal>to</literal> parameter.
+
+          See <literal>man r2e</literal> for more information on which
+          parameters are accepted.
+        '';
+      };
+
+      feeds = mkOption {
+        description = "The feeds to watch.";
+        type = types.attrsOf (types.submodule {
+          options = {
+            url = mkOption {
+              type = types.str;
+              description = "The URL at which to fetch the feed.";
+            };
+
+            to = mkOption {
+              type = with types; nullOr str;
+              default = null;
+              description = ''
+                Email address to which to send feed items.
+
+                If <literal>null</literal>, this will not be set in the
+                configuration file, and rss2email will make it default to
+                <literal>rss2email.to</literal>.
+              '';
+            };
+          };
+        });
+      };
+    };
+
+  };
+
+
+  ###### implementation
+
+  config = mkIf cfg.enable {
+    users.groups = {
+      rss2email.gid = config.ids.gids.rss2email;
+    };
+
+    users.users = {
+      rss2email = {
+        description = "rss2email user";
+        uid = config.ids.uids.rss2email;
+        group = "rss2email";
+      };
+    };
+
+    environment.systemPackages = with pkgs; [ rss2email ];
+
+    services.rss2email.config.to = cfg.to;
+
+    systemd.tmpfiles.rules = [
+      "d /var/rss2email 0700 rss2email rss2email - -"
+    ];
+
+    systemd.services.rss2email = let
+      conf = pkgs.writeText "rss2email.cfg" (lib.generators.toINI {} ({
+          DEFAULT = cfg.config;
+        } // lib.mapAttrs' (name: feed: nameValuePair "feed.${name}" (
+          { inherit (feed) url; } //
+          lib.optionalAttrs (feed.to != null) { inherit (feed) to; }
+        )) cfg.feeds
+      ));
+    in
+    {
+      preStart = ''
+        cp ${conf} /var/rss2email/conf.cfg
+        if [ ! -f /var/rss2email/db.json ]; then
+          echo '{"version":2,"feeds":[]}' > /var/rss2email/db.json
+        fi
+      '';
+      path = [ pkgs.system-sendmail ];
+      serviceConfig = {
+        ExecStart =
+          "${pkgs.rss2email}/bin/r2e -c /var/rss2email/conf.cfg -d /var/rss2email/db.json run";
+        User = "rss2email";
+      };
+    };
+
+    systemd.timers.rss2email = {
+      partOf = [ "rss2email.service" ];
+      wantedBy = [ "timers.target" ];
+      timerConfig.OnBootSec = "0";
+      timerConfig.OnUnitActiveSec = cfg.interval;
+    };
+  };
+
+  meta.maintainers = with lib.maintainers; [ ekleog ];
+}