This commits removes the locks used to guard data integrity for the
database and replaces them with Transactions, turns out that SQL had
a way to deal with this all along.
This reduces the complexity we had with multiple locks that might stack
or recurse (database, nofitifer, mapper). All notifications and state
updates are now triggered _after_ a database change.
Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>
This commit replaces the timestamp based state system with a new
one that has update channels directly to the connected nodes. It
will send an update to all listening clients via the polling
mechanism.
It introduces a new package notifier, which has a concurrency safe
manager for all our channels to the connected nodes.
Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>
This is a massive commit that restructures the code into modules:
db/
All functions related to modifying the Database
types/
All type definitions and methods that can be exclusivly used on
these types without dependencies
policy/
All Policy related code, now without dependencies on the Database.
policy/matcher/
Dedicated code to match machines in a list of FilterRules
Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>