Add get-referring-entries test

Signed-off-by: Zach Brown <zab@versity.com>

tests/golden/get-referring-entries

@@ -0,0 +1,18 @@
+== root inode returns nothing
+== crazy large unused inode does nothing
+== basic entry
+file
+== rename
+renamed
+== hard link
+file
+link
+== removal
+== different dirs
+== file types
+type b name block
+type c name char
+type d name dir
+type f name file
+type l name symlink
+== all name lengths work

tests/sequence

@@ -5,6 +5,7 @@ inode-items-updated.sh
 simple-inode-index.sh
 simple-staging.sh
 simple-release-extents.sh
+get-referring-entries.sh
 fallocate.sh
 basic-truncate.sh
 data-prealloc.sh

tests/tests/get-referring-entries.sh

@@ -0,0 +1,99 @@
+
+#
+# Test _GET_REFERRING_ENTRIES ioctl via the get-referring-entries cli
+# command
+#
+
+# consistently print only entry names
+filter_names() {
+	exec cut -d ' ' -f 8- | sort
+}
+
+# print entries with type characters to match find.  not happy with hard
+# coding, but abi won't change much.
+filter_types() {
+	exec cut -d ' ' -f 5- | \
+	sed \
+		-e 's/type 1 /type p /' \
+		-e 's/type 2 /type c /' \
+		-e 's/type 4 /type d /' \
+		-e 's/type 6 /type b /' \
+		-e 's/type 8 /type f /' \
+		-e 's/type 10 /type l /' \
+		-e 's/type 12 /type s /' \
+		| \
+	sort
+}
+
+n_chars() {
+	local n="$1"
+	printf 'A%.0s' $(eval echo {1..\$n})
+}
+
+GRE="scoutfs get-referring-entries -p $T_M0"
+
+echo "== root inode returns nothing"
+$GRE 1
+
+echo "== crazy large unused inode does nothing"
+$GRE 4611686018427387904 # 1 << 62
+
+echo "== basic entry"
+touch $T_D0/file
+ino=$(stat -c '%i' $T_D0/file)
+$GRE $ino | filter_names
+
+echo "== rename"
+mv $T_D0/file $T_D0/renamed
+$GRE $ino | filter_names
+
+echo "== hard link"
+mv $T_D0/renamed $T_D0/file
+ln $T_D0/file $T_D0/link
+$GRE $ino | filter_names
+
+echo "== removal"
+rm $T_D0/file $T_D0/link
+$GRE $ino
+
+echo "== different dirs"
+touch $T_D0/file
+ino=$(stat -c '%i' $T_D0/file)
+for i in $(seq 1 10); do
+	mkdir $T_D0/dir-$i
+	ln $T_D0/file $T_D0/dir-$i/file-$i
+done
+diff -u <(find $T_D0 -type f -printf '%f\n' | sort) <($GRE $ino | filter_names)
+rm $T_D0/file
+
+echo "== file types"
+mkdir $T_D0/dir
+touch $T_D0/dir/file
+mkdir $T_D0/dir/dir
+ln -s $T_D0/dir/file $T_D0/dir/symlink
+mknod $T_D0/dir/char c 1 3 # null
+mknod $T_D0/dir/block b 7 0 # loop0
+for name in $(ls -UA $T_D0/dir | sort); do
+	ino=$(stat -c '%i' $T_D0/dir/$name)
+	$GRE $ino | filter_types
+done
+rm -rf $T_D0/dir
+
+echo "== all name lengths work"
+mkdir $T_D0/dir
+touch $T_D0/dir/file
+ino=$(stat -c '%i' $T_D0/dir/file)
+name=""
+> $T_TMP.unsorted
+for i in $(seq 1 255); do
+	name+="a"
+	echo "$name" >> $T_TMP.unsorted
+	ln $T_D0/dir/file $T_D0/dir/$name
+done
+sort $T_TMP.unsorted > $T_TMP.sorted
+rm $T_D0/dir/file
+$GRE $ino | filter_names > $T_TMP.gre
+diff -u $T_TMP.sorted $T_TMP.gre
+rm -rf $T_D0/dir
+
+t_pass