[PATCH ipset 3/7] tests: diff.sh: preserve file name

As-is, in case of error, its not easy to see which diff file has
failed, because diff gets fed via <(sed...), so diff shows
something like
--- /dev/fd/63
+++ /dev/ ..

Take advantage of the temporary directory and output a file
that has keeps part of the original name.

Signed-off-by: Florian Westphal <[email protected]>
---
 tests/diff.sh | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/tests/diff.sh b/tests/diff.sh
index a364a28b1dda..76b1938149eb 100755
--- a/tests/diff.sh
+++ b/tests/diff.sh
@@ -1,7 +1,14 @@
 #!/bin/bash
 
-diff -u -I 'Revision: .*' -I 'Size in memory.*' \
-    <(sed -e 's/timeout [0-9]*/timeout x/' -e 's/initval 0x[0-9a-fA-F]\{8\}/initval 0x00000000/' $1) \
-    <(sed -e 's/timeout [0-9]*/timeout x/' -e 's/initval 0x[0-9a-fA-F]\{8\}/initval 0x00000000/' $2)
+NEW_DUMP="$IPSET_TMP/kernel-dump.sed"
+STORED_DUMP="$IPSET_TMP/$2.sed"
 
+sed -e 's/timeout [0-9]*/timeout x/' -e 's/initval 0x[0-9a-fA-F]\{8\}/initval 0x00000000/' "$1" > "$NEW_DUMP"
+sed -e 's/timeout [0-9]*/timeout x/' -e 's/initval 0x[0-9a-fA-F]\{8\}/initval 0x00000000/' "$2" > "$STORED_DUMP"
 
+diff -u -I 'Revision: .*' -I 'Size in memory.*' "$STORED_DUMP" "$NEW_DUMP"
+ret=$?
+
+rm -f "$STORED_DUMP" "$NEW_DUMP"
+
+exit $ret
-- 
2.54.0