tests: fix problems in the m_rootgnutar test

The mkgnutar.pl file only works if the developer had a specific
username and uid.  In addition, if it is used, the round-trip from tar
to an ext4 file system and back to tar isn't properly tested.  So only
use mkgnutar.pl if the system doesn't have GNU TAR.

In addition, make sure all of the temp files created by the test are
deleted when the test is completed.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

2 files changed, 41 insertions, 14 deletions

diff --git a/tests/m_rootgnutar/mkgnutar.pl b/tests/m_rootgnutar/mkgnutar.pl
index cb4d6c27f..516124cdb 100644
--- a/tests/m_rootgnutar/mkgnutar.pl
+++ b/tests/m_rootgnutar/mkgnutar.pl
@@ -59,6 +59,7 @@ foreach my $fname (@entries) {
     my $content = "";
     my $type;
     my $linkname = "";
+    my $username = $ENV{LOGNAME} || $ENV{USER} || getpwuid($<);
     if (S_ISLNK($mode)) {
         $type     = 2;
         $linkname = readlink $fname;
@@ -74,17 +75,18 @@ foreach my $fname (@entries) {
         'a100 a8 a8 a8 a12 a12 A8 a1 a100 a6 a2 a32 a32 a8 a8 a155 x12',
         $fname,
         sprintf('%07o',  $mode & 07777),
-        sprintf('%07o',  1000),               # uid
-        sprintf('%07o',  1000),               # gid
+        sprintf('%07o',  $<),                 # uid
+        sprintf('%07o',  $(),                 # gid
         sprintf('%011o', length $content),    # size
-        sprintf('%011o', $mtime),             # mtime
+        sprintf('%011o', $mtime),
+         # mtime
         '',                                   # checksum
         $type,
         $linkname,                            # linkname
         "ustar ",                             # magic
         " ",                                  # version
-        "josch",                              # username
-        "josch",                              # groupname
+        "$username",                          # username
+        "$username",                          # groupname
         '',                                   # dev major
         '',                                   # dev minor
         '',                                   # prefix
diff --git a/tests/m_rootgnutar/script b/tests/m_rootgnutar/script
index 3d5cd7957..79fd2225b 100644
--- a/tests/m_rootgnutar/script
+++ b/tests/m_rootgnutar/script
@@ -1,5 +1,7 @@
 # vim: filetype=sh
 
+use_mkgnutar=
+
 test_description="create fs image from GNU tarball"
 if ! test -x "$DEBUGFS_EXE"; then
 	echo "$test_name: $test_description: skipped (no debugfs)"
@@ -10,6 +12,21 @@ if [ "$(grep -c 'define HAVE_ARCHIVE_H' ../lib/config.h)" -eq 0 ]; then
 	exit 0
 fi
 
+if test -z "$use_mkgnutar" ; then
+    if type ztar > /dev/null 2>&1 && \
+	    tar --version 2>&1 | head -1 | grep -q "GNU tar" ; then
+	TAR=tar
+    elif type gtar > /dev/null 2>&1 && \
+	    gtar --version 2>&1 | head -1 | grep -q "GNU tar" ; then
+	TAR=gtar
+    else
+	# if GNU tar is not available, fall back to using mkgnutar.pl
+	use_mkgnutar=yes
+#	echo "$test_name: $test_description: skipped (no GNU tar)"
+#	exit 0
+    fi
+fi
+
 MKFS_TAR="$TMPFILE.tar"
 MKFS_DIR="$TMPFILE.dir"
 OUT="$test_name.log"
@@ -28,21 +45,26 @@ mkdir "$MKFS_DIR/test/emptydir"
 mkdir "$MKFS_DIR/test/dir"
 echo "will be overwritten" > "$MKFS_DIR/test/dir/file"
 
-if false; then
+if test -z "$use_mkgnutar"; then
 	# debugfs rdump does not preserve the timestamps when it extracts the
 	# files so we ignore them by using tar --clamp-mtime
 	# first write a partial tar
-	tar --sort=name -C "$MKFS_DIR" --mtime="$DEBUGFS_EXE" --clamp-mtime --format=gnu -cf "$MKFS_TAR.dupl" test
+    $TAR --sort=name -C "$MKFS_DIR" --mtime="$DEBUGFS_EXE" --clamp-mtime \
+	 --format=gnu -cf "$MKFS_TAR.dupl" test
 	# now overwrite the contents of a file
 	echo "Test me" > "$MKFS_DIR/test/dir/file"
 	# and update the tar so that it contains two entries for the same file
 	# we need this to test the code path that first unlinks and then overwrites an
 	# existing file
-	tar -C "$MKFS_DIR" --mtime="$DEBUGFS_EXE" --clamp-mtime --format=gnu -rf "$MKFS_TAR.dupl" test/dir/file
+	$TAR -C "$MKFS_DIR" --mtime="$DEBUGFS_EXE" --clamp-mtime \
+	     --format=gnu -rf "$MKFS_TAR.dupl" test/dir/file
 	# also add a duplicate directory entry because those must not be unlinked
-	echo test | tar -C "$MKFS_DIR" --mtime="$DEBUGFS_EXE" --clamp-mtime --format=gnu -rf "$MKFS_TAR.dupl" --no-recursion --verbatim-files-from --files-from=-
+	echo test | $TAR -C "$MKFS_DIR" --mtime="$DEBUGFS_EXE" --clamp-mtime \
+			 --format=gnu -rf "$MKFS_TAR.dupl" --no-recursion \
+			 --verbatim-files-from --files-from=-
 	# also create a tarball of the directory with only one entry per file
-	tar --sort=name -C "$MKFS_DIR" --mtime="$DEBUGFS_EXE" --clamp-mtime --format=gnu -cf "$MKFS_TAR.uniq" test
+	$TAR --sort=name -C "$MKFS_DIR" --mtime="$DEBUGFS_EXE" --clamp-mtime \
+	     --format=gnu -cf "$MKFS_TAR.uniq" test
 else
 	# same as above but without using GNU tar
 	perl $test_dir/mkgnutar.pl --nopadding --directory="$MKFS_DIR" --mtime "$DEBUGFS_EXE_MTIME" test > "$MKFS_TAR.dupl"
@@ -102,9 +124,11 @@ for ext in uniq dupl; do
 		$DEBUGFS -R "rdump /test $MKFS_DIR" "$TMPFILE.$ext" 2>&1;
 		echo Exit status is $?;
 		# debugfs rdump does not preserve the timestamps when it extracts the
-		# files so we ignore them by using tar --clamp-mtime
-		if false; then
-			tar --sort=name -C "$MKFS_DIR" --mtime="$DEBUGFS_EXE" --clamp-mtime --format=gnu -cvf "$TMPFILE.new.tar" test 2>&1;
+		if test -z "$use_mkgnutar"; then
+			# files so we ignore them by using tar --clamp-mtime
+		    $TAR --sort=name -C "$MKFS_DIR" \
+			 --mtime="$DEBUGFS_EXE" --clamp-mtime --format=gnu \
+			 -cvf "$TMPFILE.new.tar" test 2>&1;
 		else
 			perl $test_dir/mkgnutar.pl --verbose --directory="$MKFS_DIR" --mtime "$DEBUGFS_EXE_MTIME" test 2>&1 > "$TMPFILE.new.tar";
 		fi;
@@ -140,5 +164,6 @@ else
 	diff $DIFF_OPTS "$EXP" "$OUT" > "$test_name.failed"
 fi
 
-rm -rf "$MKFS_TAR.dupl" "$MKFS_TAR.uniq" "$TMPFILE.cmd1" "$TMPFILE.cmd2" "$TMPFILE.log"
+rm -rf "$MKFS_TAR.dupl" "$MKFS_TAR.uniq" "$TMPFILE.cmd1" "$TMPFILE.cmd2" \
+   "$TMPFILE.log" "$TMPFILE.dupl" "$TMPFILE.uniq" "$TMPFILE.testme"
 unset MKFS_TAR MKFS_DIR OUT EXP