Support 'nft -f -' to read from stdin

In libnftables, detect if given filename is '-' and treat it as the
common way of requesting to read from stdin, then open /dev/stdin
instead. (Calling 'nft -f /dev/stdin' worked before as well, but this
makes it official.)

With this in place and bash's support for here strings, review all tests
in tests/shell for needless use of temp files. Note that two categories
of test cases were intentionally left unchanged:

- Tests creating potentially large rulesets to avoid running into shell
  parameter length limits.
- Tests for 'include' directive for obvious reasons.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 1 insertions, 10 deletions

diff --git a/tests/shell/testcases/transactions/0014chain_1 b/tests/shell/testcases/transactions/0014chain_1
index 955860d0..40cea8b2 100755
--- a/tests/shell/testcases/transactions/0014chain_1
+++ b/tests/shell/testcases/transactions/0014chain_1
@@ -2,19 +2,10 @@
 
 set -e
 
-tmpfile=$(mktemp)
-if [ ! -w $tmpfile ] ; then
-        echo "Failed to create tmp file" >&2
-        exit 0
-fi
-
-trap "rm -rf $tmpfile" EXIT # cleanup if aborted
-
 RULESET="add table x
 add chain x y
 delete chain x y
 delete chain x y"
 
-echo "$RULESET" > $tmpfile
-$NFT -f $tmpfile 2>/dev/null
+$NFT -f - <<< $RULESET 2>/dev/null
 echo "E: allowing double-removal of chain" >&2