This patch adds xid support to du.

diff -Naurp coreutils-5.2.1.orig/configure.ac coreutils-5.2.1/configure.ac
--- coreutils-5.2.1.orig/configure.ac	2004-03-02 23:47:31.000000000 +0100
+++ coreutils-5.2.1/configure.ac	2005-02-20 02:00:51.000000000 +0100
@@ -235,6 +235,10 @@ jm_LIB_CHECK
 AM_GNU_GETTEXT([external], [need-ngettext])
 AM_GNU_GETTEXT_VERSION(0.13.1)
 
+dnl vserver check
+AC_CHECK_LIB([vserver], [vc_get_iattr])
+AC_CHECK_TYPES([xid_t, nid_t])
+
 AC_CONFIG_FILES(
   Makefile
   doc/Makefile
diff -Naurp coreutils-5.2.1.orig/src/du.c coreutils-5.2.1/src/du.c
--- coreutils-5.2.1.orig/src/du.c	2004-02-22 22:21:35.000000000 +0100
+++ coreutils-5.2.1/src/du.c	2005-02-20 01:58:42.000000000 +0100
@@ -41,6 +41,15 @@
 #include "same.h"
 #include "xfts.h"
 #include "xstrtol.h"
+#ifdef HAVE_LIBVSERVER
+#ifndef HAVE_XID_T
+typedef unsigned int xid_t;
+#endif
+#ifndef HAVE_NID_T
+typedef unsigned int nid_t;
+#endif
+#include <vserver.h>
+#endif
 
 extern int fts_debug;
 
@@ -115,6 +124,11 @@ static uintmax_t tot_size = 0;
 /* Nonzero indicates that du should exit with EXIT_FAILURE upon completion.  */
 int G_fail;
 
+#ifdef HAVE_LIBVSERVER
+/* xid to sum files for */
+xid_t xid = VC_NOCTX;
+#endif
+
 #define IS_DIR_TYPE(Type)	\
   ((Type) == FTS_DP		\
    || (Type) == FTS_DNR)
@@ -151,6 +165,9 @@ static struct option const long_options[
   {"separate-dirs", no_argument, NULL, 'S'},
   {"summarize", no_argument, NULL, 's'},
   {"total", no_argument, NULL, 'c'},
+#ifdef HAVE_LIBVSERVER
+  {"xid", required_argument, NULL, 'C'},
+#endif
   {GETOPT_HELP_OPTION_DECL},
   {GETOPT_VERSION_OPTION_DECL},
   {NULL, 0, NULL, 0}
@@ -365,12 +382,19 @@ process_file (FTS *fts, FTSENT *ent)
   if (ent->fts_info == FTS_D || skip)
     return;
 
-  /* If the file is being excluded or if it has already been counted
-     via a hard link, then don't let it contribute to the sums.  */
+  /* If the file is being excluded, if it has already been counted
+     via a hard link, or if it's xid is wrong and it's not a
+     directory, then don't let it contribute to the sums.  */
   if (skip
       || (!opt_count_all
 	  && 1 < sb->st_nlink
-	  && hash_ins (sb->st_ino, sb->st_dev)))
+	  && hash_ins (sb->st_ino, sb->st_dev))
+#ifdef HAVE_LIBVSERVER
+      || (xid != VC_NOCTX
+	  && !IS_DIR_TYPE(ent->fts_info)
+	  && vc_getfilecontext(ent->fts_name) != xid)
+#endif
+    )
     {
       /* Note that we must not simply return here.
 	 We still have to update prev_level and maybe propagate
@@ -681,6 +705,21 @@ main (int argc, char **argv)
 	  add_exclude (exclude, optarg, EXCLUDE_WILDCARDS);
 	  break;
 
+#ifdef HAVE_LIBVSERVER
+	case 'C':
+	  {
+	    const char *errstr = NULL;
+	    xid = vc_xidopt2xid(optarg, true, &errstr);
+	    if (xid == VC_NOCTX)
+	      {
+		error (0, 0, _("invalid xid %s: %s"),
+		       quote (optarg), errstr);
+		fail = 1;
+	      }
+	  }
+	  break;
+#endif
+
 	case_GETOPT_HELP_CHAR;
 
 	case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);