Bugfix - fix xattr exclude/include for archive create

This makes archive create behavior consistent with the
documentation.  Without this change xattr include/exclude options
are accepted when creating an archive but are silently ignored.

* src/xattrs.c (xattrs_xattrs_get): Apply exclude/include mask
when fetching extended attributes
* tests/Makefile.am: Add new test case.
* tests/testsuite.at: Likewise.

src/xattrs.c

@@ -434,8 +434,12 @@ xattrs_clear_setup (void)
   clear_mask_map (&xattrs_setup.excl);
 }
 
-/* get all xattrs from file given by FILE_NAME or FD (when non-zero).  This
-   includes all the user.*, security.*, system.*, etc. available domains */
+static bool xattrs_masked_out (const char *kw, bool archiving);
+
+/* get xattrs from file given by FILE_NAME or FD (when non-zero)
+   xattrs are checked against the user supplied include/exclude mask
+   if no mask is given this includes all the user.*, security.*, system.*,
+   etc. available domains */
 void
 xattrs_xattrs_get (int parentfd, char const *file_name,
                    struct tar_stat_info *st, int fd)
@@ -480,8 +484,6 @@ xattrs_xattrs_get (int parentfd, char const *file_name,
               size_t len = strlen (attr);
               ssize_t aret = 0;
 
-              /* Archive all xattrs during creation, decide at extraction time
-               * which ones are of interest/use for the target filesystem. */
               while (((fd == 0)
                       ? ((aret = lgetxattrat (parentfd, file_name, attr,
                                               val, asz)) == -1)
@@ -492,7 +494,10 @@ xattrs_xattrs_get (int parentfd, char const *file_name,
                 }
 
               if (aret != -1)
-                xheader_xattr_add (st, attr, val, aret);
+                {
+                  if (!xattrs_masked_out(attr, true))
+                    xheader_xattr_add (st, attr, val, aret);
+                }
               else if (errno != ENOATTR)
                 call_arg_warn ((fd == 0) ? "lgetxattrat"
                                : "fgetxattr", file_name);

tests/Makefile.am

@@ -246,6 +246,7 @@ TESTSUITE_AT = \
  xattr03.at\
  xattr04.at\
  xattr05.at\
+ xattr06.at\
  acls01.at\
  acls02.at\
  acls03.at\

tests/testsuite.at

@@ -445,6 +445,7 @@ m4_include([xattr02.at])
 m4_include([xattr03.at])
 m4_include([xattr04.at])
 m4_include([xattr05.at])
+m4_include([xattr06.at])
 
 m4_include([acls01.at])
 m4_include([acls02.at])

tests/xattr06.at

@@ -0,0 +1,51 @@
+# Process this file with autom4te to create testsuite. -*- Autotest -*-
+#
+# Test suite for GNU tar.
+# Copyright 2012-2014, 2016 Free Software Foundation, Inc.
+
+# This file is part of GNU tar.
+
+# GNU tar 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 of the License, or
+# (at your option) any later version.
+
+# GNU tar 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/>.
+#
+# Test description:  Test for exclude of xattr during archive creation
+#
+# Relevant mailing list thread:
+#
+# http://lists.gnu.org/archive/html/bug-tar/2016-05/msg00031.html
+
+AT_SETUP([xattrs: exclude xattrs on create ])
+AT_KEYWORDS([xattrs xattr06])
+
+AT_TAR_CHECK([
+AT_XATTRS_PREREQ
+
+mkdir dir
+mkdir output
+genfile --file dir/file
+
+setfattr -n user.excludedxattr -v value dir/file
+
+# exclude the attribute we just set
+tar --xattrs --xattrs-exclude=user.excludedxattr -cf archive.tar -C dir .
+
+tar --xattrs -xf archive.tar -C output
+getfattr -d output/file | grep -v excludedxattr > without
+getfattr -d output/file > with
+# if they differ then the attribute is still present
+diff without with
+],
+[0],
+[])
+
+AT_CLEANUP