Implement ISOBUS File Server (FS) Interface as a Personal Project

Introduce the ISOBUS File Server (FS) interface, compatible with ISO
11783-13. The implementation utilizes the kernel's existing CAN J1939
socket support.

For testing following setup can be used:
ip link add type vcan
ip l s dev vcan0 up

j1939acd -r 64-95 -c /tmp/1122334455667788.jacd 1122334455667788 vcan0 &
j1939acd -r 96-127 -c /tmp/1122334455667789.jacd 1122334455667789 vcan0 &

sleep 1

isobusfs-srv -i vcan0 -n 1122334455667788 -v vol1:/path/to/export/
isobusfs-cli -i vcan0 -n 0x1122334455667789 -m 0x1122334455667788 -I

Interactive mode currently support following commands:
exit - exit interactive mode
quit - exit interactive mode
help - show this help
dmesg - show log buffer
selftest - run selftest
ls - list directory
ll - list directory with long listing format
cd - change directory
pwd - print name of current/working directory
get - get file

Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>

.gitignore

@@ -38,6 +38,8 @@ GNUmakefile.in
 /cansend
 /cansequence
 /cansniffer
+/isobusfs-cli
+/isobusfs-srv
 /isotpdump
 /isotpperf
 /isotprecv