Do not create duplicate udev attributes

[teclator]

Problem

• https://bugzilla.suse.com/show_bug.cgi?id=1137324

When editing an interface name.

If no previous udev rule exist and the udev rule to be written is based on the interface :mac, then it generates a duplicate attribute:

Something like:

SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="9c:eb:e8:1a:d2:2f", ATTR{dev_id}=="0x0", ATTR{type}=="1", ATTR{address}=="9c:eb:e8:1a:d2:2f", NAME="eth1"

That also happens with an existent rule and pressing 'OK' without modifying the key attribute.

In combination with this another bug the situation is even worworst because there could be two different mac addresses, the current and the permanent one.

Solution

When editing an interface name:

1.- The rule only will be updated if the matching attribute or value from the original differs.
2.- The update_item_udev_rule! method will check if a rule already exist and if not will initialize it. As the default rule is based on :mac, we will return after initialization in case the update rule is based on :mac.

Testing

• Added a new unit test for the new current udev rule method
• Tested manually

[coveralls]

Coverage increased (+0.03%) to 31.135% when pulling 030fd03 on duplicate_udev_key into 4b950ad on SLE-12-SP4.

[mchf]

lgtm