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/databases/dragonflydb.nix

@@ -0,0 +1,152 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.dragonflydb;
+  dragonflydb = pkgs.dragonflydb;
+
+  settings =
+    {
+      port = cfg.port;
+      dir = "/var/lib/dragonflydb";
+      keys_output_limit = cfg.keysOutputLimit;
+    } //
+    (lib.optionalAttrs (cfg.bind != null) { bind = cfg.bind; }) //
+    (lib.optionalAttrs (cfg.requirePass != null) { requirepass = cfg.requirePass; }) //
+    (lib.optionalAttrs (cfg.maxMemory != null) { maxmemory = cfg.maxMemory; }) //
+    (lib.optionalAttrs (cfg.memcachePort != null) { memcache_port = cfg.memcachePort; }) //
+    (lib.optionalAttrs (cfg.dbNum != null) { dbnum = cfg.dbNum; }) //
+    (lib.optionalAttrs (cfg.cacheMode != null) { cache_mode = cfg.cacheMode; });
+in
+{
+
+  ###### interface
+
+  options = {
+    services.dragonflydb = {
+      enable = mkEnableOption "DragonflyDB";
+
+      user = mkOption {
+        type = types.str;
+        default = "dragonfly";
+        description = "The user to run DragonflyDB as";
+      };
+
+      port = mkOption {
+        type = types.port;
+        default = 6379;
+        description = "The TCP port to accept connections.";
+      };
+
+      bind = mkOption {
+        type = with types; nullOr str;
+        default = "127.0.0.1";
+        description = ''
+          The IP interface to bind to.
+          <literal>null</literal> means "all interfaces".
+        '';
+      };
+
+      requirePass = mkOption {
+        type = with types; nullOr str;
+        default = null;
+        description = "Password for database";
+        example = "letmein!";
+      };
+
+      maxMemory = mkOption {
+        type = with types; nullOr ints.unsigned;
+        default = null;
+        description = ''
+          The maximum amount of memory to use for storage (in bytes).
+          <literal>null</literal> means this will be automatically set.
+        '';
+      };
+
+      memcachePort = mkOption {
+        type = with types; nullOr port;
+        default = null;
+        description = ''
+          To enable memcached compatible API on this port.
+          <literal>null</literal> means disabled.
+        '';
+      };
+
+      keysOutputLimit = mkOption {
+        type = types.ints.unsigned;
+        default = 8192;
+        description = ''
+          Maximum number of returned keys in keys command.
+          <literal>keys</literal> is a dangerous command.
+          We truncate its result to avoid blowup in memory when fetching too many keys.
+        '';
+      };
+
+      dbNum = mkOption {
+        type = with types; nullOr ints.unsigned;
+        default = null;
+        description = "Maximum number of supported databases for <literal>select</literal>";
+      };
+
+      cacheMode = mkOption {
+        type = with types; nullOr bool;
+        default = null;
+        description = ''
+          Once this mode is on, Dragonfly will evict items least likely to be stumbled
+          upon in the future but only when it is near maxmemory limit.
+        '';
+      };
+    };
+  };
+
+  ###### implementation
+
+  config = mkIf config.services.dragonflydb.enable {
+
+    users.users = optionalAttrs (cfg.user == "dragonfly") {
+      dragonfly.description = "DragonflyDB server user";
+      dragonfly.isSystemUser = true;
+      dragonfly.group = "dragonfly";
+    };
+    users.groups = optionalAttrs (cfg.user == "dragonfly") { dragonfly = { }; };
+
+    environment.systemPackages = [ dragonflydb ];
+
+    systemd.services.dragonflydb = {
+      description = "DragonflyDB server";
+
+      wantedBy = [ "multi-user.target" ];
+      after = [ "network.target" ];
+
+      serviceConfig = {
+        ExecStart = "${dragonflydb}/bin/dragonfly --alsologtostderr ${builtins.concatStringsSep " " (attrsets.mapAttrsToList (n: v: "--${n} ${strings.escapeShellArg v}") settings)}";
+
+        User = cfg.user;
+
+        # Filesystem access
+        ReadWritePaths = [ settings.dir ];
+        StateDirectory = "dragonflydb";
+        StateDirectoryMode = "0700";
+        # Process Properties
+        LimitMEMLOCK = "infinity";
+        # Caps
+        CapabilityBoundingSet = "";
+        NoNewPrivileges = true;
+        # Sandboxing
+        ProtectSystem = "strict";
+        ProtectHome = true;
+        PrivateTmp = true;
+        PrivateDevices = true;
+        ProtectKernelTunables = true;
+        ProtectKernelModules = true;
+        ProtectControlGroups = true;
+        LockPersonality = true;
+        RestrictAddressFamilies = [ "AF_INET" "AF_INET6" ];
+        RestrictRealtime = true;
+        PrivateMounts = true;
+        MemoryDenyWriteExecute = true;
+      };
+    };
+  };
+}