systemconfig: chown files if uid/gid > 0

pkgs/systemconfig/default.nix

@@ -28,8 +28,6 @@ let
           , uid ? 0
           , gid ? 0
         }:
-          assert uid == 0;
-          assert gid == 0;
           let
             pathname = "${prefix}/${filename}";
             qpathname = builtins.toJSON pathname;
@@ -49,7 +47,10 @@ let
               "i" = "MKNOD_P(${qpathname}, ${mode'});";
             };
             cmd = cmds.${type};
-          in "${cmd}";
+            chown = if uid>0 || gid>0
+                    then "\nCHOWN(${qpathname},${toString uid},${toString gid});\n"
+                    else "";
+          in "${cmd} ${chown}";
     in mapAttrsToList (makeFile prefix) attrset;
   activateScript = attrset: writeText "makedevs.c" ''
     #include "defs.h"

pkgs/systemconfig/defs.h

@@ -35,3 +35,4 @@ void print_file(char * path, mode_t mode, char * text) {
 #define LN_S(target, path) (void)symlink(target, path)
 #define LN(target, path) link(target, path)
 #define MKNOD_P(path, mode) mkfifo(path, mode)
+#define CHOWN(path, uid, gid) chown(path, uid, gid)

tests/jffs2/configuration.nix

@@ -1,8 +1,19 @@
 { config, pkgs, lib, ... } :
-{
+let
+  inherit (pkgs.pseudofile) dir symlink;
+in {
   imports = [
     ../../vanilla-configuration.nix
+    ../../modules/squashfs.nix
     ../../modules/jffs2.nix
   ];
   config.rootfsType = "jffs2";
+  config.filesystem = dir {
+    hello = {
+      type = "f";
+      uid = 7;
+      gid = 24;
+      file = "hello world";
+    };
+  };
 }