some slight cleanup in setuid code

src/main.c

@@ -229,18 +229,14 @@ void establishListen(Options * options) {
 
 void changeToUser(Options * options) {
         if (options->usr && strlen(options->usr)) {
-                int uid, gid;
-
                 /* get uid */
                 struct passwd * userpwd;
                 if ((userpwd = getpwnam(options->usr)) == NULL) {
                         ERROR("no such user: %s\n", options->usr);
                         exit(EXIT_FAILURE);
                 }
-                uid = userpwd->pw_uid;
-                gid = userpwd->pw_gid;
 
-                if(setgid(gid) == -1) {
+                if(setgid(userpwd->pw_gid) == -1) {
                         ERROR("cannot setgid of user %s: %s\n", options->usr,
                                         strerror(errno));
                         exit(EXIT_FAILURE);
@@ -250,7 +246,7 @@ void changeToUser(Options * options) {
                 /* init suplementary groups 
                  * (must be done before we change our uid)
                  */
-                if (initgroups(options->usr, gid) == -1) {
+                if (initgroups(options->usr, userpwd->pw_gid) == -1) {
                         WARNING("cannot init suplementary groups "
                                         "of user %s: %s\n", options->usr, 
                                         strerror(errno));
@@ -258,7 +254,7 @@ void changeToUser(Options * options) {
 #endif
 
                 /* set uid */
-                if (setuid(uid) == -1) {
+                if (setuid(userpwd->pw_uid) == -1) {
                         ERROR("cannot change to uid of user "
                                         "%s: %s\n", options->usr, 
                                         strerror(errno));