Firearm safety varies widely between models IRL, extrapolate that into 2075. I would use the following as a guide, but adjust according to weapon, owners preference, and other circumstances.
No Link: weapon is ready to go, can be fired by anyone holding it, unless other safety measures in place.
External Smartlink: weapon has been modified to fire wirelessly, but that would not exclude manual operation. The weapon should be capable of firing, but with no benefit from the smartlink unless marks are added.
Internal Smartlink: the smartlink has been fully integrated into the weapon, only a registered user or owner can fire it.