[PATCH] tests: add skips when IPv6 is not supported

[LiviaMedeiros <9@xxxxxxxxxx>]

From: LiviaMedeiros <livia@xxxxxxxxxx>

Before this change on systems with disabled IPv6 (e.g. `CONFIG_IPV6 is 
not set` in kernel config), `lsfd/mkfds-tcp6` and `lsfd/mkfds-udp6` were 
failing, and `lsfd/option-inet` was hanging forever, making it 
impossible to complete the tests.

Signed-off-by: LiviaMedeiros <livia@xxxxxxxxxx>
---
 tests/functions.sh        | 6 ++++++
 tests/ts/lsfd/mkfds-tcp6  | 1 +
 tests/ts/lsfd/mkfds-udp6  | 1 +
 tests/ts/lsfd/option-inet | 1 +
 4 files changed, 9 insertions(+)

diff --git a/tests/functions.sh b/tests/functions.sh
index 630166871..add50440b 100644
--- a/tests/functions.sh
+++ b/tests/functions.sh
@@ -1195,3 +1195,9 @@ function ts_check_enosys_syscalls {
 function ts_skip_docker {
        test -e /.dockerenv && ts_skip "unsupported in docker environment"
 }
+
+function ts_check_ipv6 {
+       if [ ! -e /proc/net/if_inet6 ]; then
+               ts_skip "IPv6 is not supported"
+       fi
+}
diff --git a/tests/ts/lsfd/mkfds-tcp6 b/tests/ts/lsfd/mkfds-tcp6
index bffa630c4..414777f4a 100755
--- a/tests/ts/lsfd/mkfds-tcp6
+++ b/tests/ts/lsfd/mkfds-tcp6
@@ -23,6 +23,7 @@ ts_init "$*"
 ts_check_test_command "$TS_CMD_LSFD"
 ts_check_test_command "$TS_HELPER_MKFDS"
 ts_check_native_byteorder
+ts_check_ipv6
 ts_skip_docker

 ts_cd "$TS_OUTDIR"
diff --git a/tests/ts/lsfd/mkfds-udp6 b/tests/ts/lsfd/mkfds-udp6
index 26bdacd7c..59b1c06a2 100755
--- a/tests/ts/lsfd/mkfds-udp6
+++ b/tests/ts/lsfd/mkfds-udp6
@@ -23,6 +23,7 @@ ts_init "$*"
 ts_check_test_command "$TS_CMD_LSFD"
 ts_check_test_command "$TS_HELPER_MKFDS"
 ts_check_native_byteorder
+ts_check_ipv6
 ts_skip_docker

 ts_cd "$TS_OUTDIR"
diff --git a/tests/ts/lsfd/option-inet b/tests/ts/lsfd/option-inet
index 7ca883751..f679f121d 100755
--- a/tests/ts/lsfd/option-inet
+++ b/tests/ts/lsfd/option-inet
@@ -24,6 +24,7 @@ ts_skip_docker

 ts_check_test_command "$TS_CMD_LSFD"
 ts_check_test_command "$TS_HELPER_MKFDS"
+ts_check_ipv6

 ts_check_prog "mkfifo"

--
2.47.1