Fix creation of incremental archives when a subdirectory becomes a mountpoint.

When used with --listed-incrfental and --one-file-system, tar
was unable to cope with directories that had once been part of the
dumped system and became separate mount points afterwards.  The bug
has been reported and a fix proposed by Nathan Stratton Treadway.

* src/incremen.c (procdir): If one_file_system_option is in effect,
clear out dumpdir info from the directory.
* tests/Makefile.am: Add new testcase.
* tests/listed05.at: New testcase.
* tests/testsuite.at (AT_PRIVILEGED_PREREQ): New macro.
include listed05.at.
* THANKS: Update.

tests/Makefile.am

@@ -114,6 +114,7 @@ TESTSUITE_AT = \
  listed02.at\
  listed03.at\
  listed04.at\
+ listed05.at\
  long01.at\
  longv7.at\
  lustar01.at\

tests/listed05.at

@@ -0,0 +1,76 @@
+# Process this file with autom4te to create testsuite. -*- Autotest -*-
+#
+# Test suite for GNU tar.
+# Copyright (C) 2010 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Tar up to 1.26 was unable to cope with directories that had once
+# been part of the dumped system and became separate mount points
+# afterwards.  The bug has been reported by Nathan Stratton Treadway,
+# who also proposed a fix and a testcase, on which the present one is
+# built.
+# Reported-by: Nathan Stratton Treadway <nathanst+bugtar@ontko.com>
+# Last-Affected-Version: 1.26
+# References: <20120527212417.GR2654@shire.ontko.com>
+#         http://lists.gnu.org/archive/html/bug-tar/2012-05/msg00022.html
+
+# This testcase is Linux-specific and requires root privileges.
+
+AT_SETUP([--listed-incremental and remounted directories])
+AT_KEYWORDS([listed incremental listed05])
+
+AT_TAR_CHECK([
+AT_PRIVILEGED_PREREQ
+options="-C tartest --create --one-file-system --verbose"
+rm -rf archive-[01].snar archive-[01].tar tartest subdir
+
+# Create initial structure
+mkdir tartest
+echo "hi" > tartest/top-level-file
+mkdir tartest/subdir
+echo "hi" > tartest/subdir/subdir-file
+
+echo "# Level 0"
+tar $options --file archive-0.tar --listed-incremental=archive-0.snar .
+
+echo "# Remount"
+mv tartest/subdir .
+mkdir tartest/subdir
+mount -t ramfs none tartest/subdir || AT_SKIP_TEST
+tar -C subdir -c -f - . | tar -C tartest/subdir -x -f -
+
+echo "# Level 1"
+cp archive-0.snar archive-1.snar
+tar $options --file archive-1.tar --listed-incremental=archive-1.snar .
+
+umount tartest/subdir
+],
+[0],
+[# Level 0
+./
+./subdir/
+./top-level-file
+./subdir/subdir-file
+# Remount
+# Level 1
+./
+./subdir/
+],
+[tar: .: Directory is new
+tar: ./subdir: Directory is new
+tar: ./subdir: directory is on a different filesystem; not dumped
+],[],[],[gnu])
+
+AT_CLEANUP

tests/testsuite.at

@@ -103,6 +103,16 @@ rm -f $[]$
 test $result -eq 0 && AT_SKIP_TEST
 ])
 
+dnl AT_PRIVILEGED_PREREQ - Skip test if not running at root privileges
+m4_define([AT_PRIVILEGED_PREREQ],[
+echo "test" > $[]$
+chmod 0 $[]$
+cat $[]$ > /dev/null 2>&1
+result=$?
+rm -f $[]$
+test $result -eq 0 || AT_SKIP_TEST
+])
+
 m4_define([AT_TAR_MKHIER],[
 install-sh -d $1 >/dev/null dnl
 m4_if([$2],,,&& genfile --file [$1]/[$2]) || AT_SKIP_TEST])
@@ -186,6 +196,7 @@ m4_include([listed01.at])
 m4_include([listed02.at])
 m4_include([listed03.at])
 m4_include([listed04.at])
+m4_include([listed05.at])
 m4_include([incr03.at])
 m4_include([incr04.at])
 m4_include([incr05.at])