The tracking database can be opened in read-only or read-write
mode. Knowing which is being used is significant in concurrent
scenarios, e.g. it's safer to have a read-only handle on multiple
threads.
Provide static type information by signifying what kind of database
handle is being worked with, read or read-write.
Signed-off-by: Fintan Halpenny <fintan.halpenny@gmail.com>
X-Clacks-Overhead: GNU Terry Pratchett
dfa7ba1df5