selftests/net: add lib.sh

Add a lib.sh for net selftests. This file can be used to define commonly
used variables and functions. Some commonly used functions can be moved
from forwarding/lib.sh to this lib file. e.g. busywait().

Add function setup_ns() for user to create unique namespaces with given
prefix name.

Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

tools/testing/selftests/net/Makefile

@@ -54,7 +54,7 @@ TEST_PROGS += ip_local_port_range.sh
 TEST_PROGS += rps_default_mask.sh
 TEST_PROGS += big_tcp.sh
 TEST_PROGS_EXTENDED := in_netns.sh setup_loopback.sh setup_veth.sh
-TEST_PROGS_EXTENDED += toeplitz_client.sh toeplitz.sh
+TEST_PROGS_EXTENDED += toeplitz_client.sh toeplitz.sh lib.sh
 TEST_GEN_FILES =  socket nettest
 TEST_GEN_FILES += psock_fanout psock_tpacket msg_zerocopy reuseport_addr_any
 TEST_GEN_FILES += tcp_mmap tcp_inq psock_snd txring_overwrite

tools/testing/selftests/net/forwarding/lib.sh

@@ -4,9 +4,6 @@
 ##############################################################################
 # Defines
 
-# Kselftest framework requirement - SKIP code is 4.
-ksft_skip=4
-
 # Can be overridden by the configuration file.
 PING=${PING:=ping}
 PING6=${PING6:=ping6}
@@ -41,6 +38,7 @@ if [[ -f $relative_path/forwarding.config ]]; then
 	source "$relative_path/forwarding.config"
 fi
 
+source ../lib.sh
 ##############################################################################
 # Sanity checks
 
@@ -395,29 +393,6 @@ log_info()
 	echo "INFO: $msg"
 }
 
-busywait()
-{
-	local timeout=$1; shift
-
-	local start_time="$(date -u +%s%3N)"
-	while true
-	do
-		local out
-		out=$("$@")
-		local ret=$?
-		if ((!ret)); then
-			echo -n "$out"
-			return 0
-		fi
-
-		local current_time="$(date -u +%s%3N)"
-		if ((current_time - start_time > timeout)); then
-			echo -n "$out"
-			return 1
-		fi
-	done
-}
-
 not()
 {
 	"$@"

tools/testing/selftests/net/lib.sh

@@ -0,0 +1,85 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+##############################################################################
+# Defines
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+##############################################################################
+# Helpers
+busywait()
+{
+	local timeout=$1; shift
+
+	local start_time="$(date -u +%s%3N)"
+	while true
+	do
+		local out
+		out=$("$@")
+		local ret=$?
+		if ((!ret)); then
+			echo -n "$out"
+			return 0
+		fi
+
+		local current_time="$(date -u +%s%3N)"
+		if ((current_time - start_time > timeout)); then
+			echo -n "$out"
+			return 1
+		fi
+	done
+}
+
+cleanup_ns()
+{
+	local ns=""
+	local errexit=0
+	local ret=0
+
+	# disable errexit temporary
+	if [[ $- =~ "e" ]]; then
+		errexit=1
+		set +e
+	fi
+
+	for ns in "$@"; do
+		ip netns delete "${ns}" &> /dev/null
+		if ! busywait 2 ip netns list \| grep -vq "^$ns$" &> /dev/null; then
+			echo "Warn: Failed to remove namespace $ns"
+			ret=1
+		fi
+	done
+
+	[ $errexit -eq 1 ] && set -e
+	return $ret
+}
+
+# setup netns with given names as prefix. e.g
+# setup_ns local remote
+setup_ns()
+{
+	local ns=""
+	local ns_name=""
+	local ns_list=""
+	for ns_name in "$@"; do
+		# Some test may setup/remove same netns multi times
+		if unset ${ns_name} 2> /dev/null; then
+			ns="${ns_name,,}-$(mktemp -u XXXXXX)"
+			eval readonly ${ns_name}="$ns"
+		else
+			eval ns='$'${ns_name}
+			cleanup_ns "$ns"
+
+		fi
+
+		if ! ip netns add "$ns"; then
+			echo "Failed to create namespace $ns_name"
+			cleanup_ns "$ns_list"
+			return $ksft_skip
+		fi
+		ip -n "$ns" link set lo up
+		ns_list="$ns_list $ns"
+	done
+}