Adding/removing capabilities when updating a service is considered a tri-state;
- if the capability was previously "dropped", then remove it from "CapabilityDrop",
but do NOT add it to "CapabilityAdd". However, if the capability was not yet in
the service's "CapabilityDrop", then simply add it to the service's "CapabilityAdd"
- likewise, if the capability was previously "added", then remove it from
"CapabilityAdd", but do NOT add it to "CapabilityDrop". If the capability was
not yet in the service's "CapabilityAdd", then simply add it to the service's
"CapabilityDrop".
In other words, given a service with the following:
| CapDrop | CapAdd |
| -------------- | ------------- |
| CAP_SOME_CAP | |
When updating the service, and applying `--cap-add CAP_SOME_CAP`, the previously
dropped capability is removed:
| CapDrop | CapAdd |
| -------------- | ------------- |
| | |
When updating the service a second time, applying `--cap-add CAP_SOME_CAP`,
capability is now added:
| CapDrop | CapAdd |
| -------------- | ------------- |
| | CAP_SOME_CAP |
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>