[gentoo-commits] proj/netifrc:master commit in: net/

["Robin H. Johnson" <robbat2@gentoo.org>]

commit:     8b4f91a94fad6666c957304b0108aa5c895b4d1e
Author:     Matoro Mahri <matoro_gentoo <AT> matoro <DOT> tk>
AuthorDate: Sat Nov 25 18:17:41 2023 +0000
Commit:     Robin H. Johnson <robbat2 <AT> gentoo <DOT> org>
CommitDate: Sun Nov 26 05:30:57 2023 +0000
URL:        https://gitweb.gentoo.org/proj/netifrc.git/commit/?id=8b4f91a9

net/dummy.sh: preload module, create interface conditionally

The dummy module has a numdummies parameter which will cause it to
automatically create N dummy interfaces at load time.  Because creating
a dummy interface causes the kernel to load the module if it is not
already loaded, then if the name of the interface to be created matches
the name of one of the interfaces the kernel creates, an error will be
returned indicating that the interface already exists, despite it not
existing before the command was invoked.

Ensure we load the module before attempting to create any interface,
then only create the interface if it does not already exist, otherwise
simply configure it.

See: https://serverfault.com/q/839430
Signed-off-by: Matoro Mahri <matoro_gentoo <AT> matoro.tk>
Signed-off-by: Robin H. Johnson <robbat2 <AT> gentoo.org>
Closes: https://github.com/gentoo/netifrc/pull/43

 net/dummy.sh | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/net/dummy.sh b/net/dummy.sh
index 091e08c..94437c3 100644
--- a/net/dummy.sh
+++ b/net/dummy.sh
@@ -25,12 +25,18 @@ dummy_pre_start()
 	eval dummy="\$type_${IFVAR}"
 	[ "${dummy}" = "dummy" ] || return 0
 
-	ebegin "Creating dummy interface ${IFACE}"
-	if _ip link add name "${IFACE}" type dummy ; then
-		eend 0 && _up && set_interface_type dummy
-	else
-		eend 1
+	if ! test -d /sys/module/dummy && ! modprobe dummy; then
+		eerror "Couldn't load the dummy module (perhaps the CONFIG_DUMMY kernel option is disabled)"
+		return 1
 	fi
+
+	if ! _exists ; then
+		ebegin "Creating dummy interface ${IFACE}"
+		_ip link add name "${IFACE}" type dummy
+		eend $?
+	fi
+
+	_up && set_interface_type dummy
 }