d416ae560e walletdb: Introduce WalletDatabase abstract class (Andrew Chow)
2179dbcbcd walletdb: Add BerkeleyDatabase::Open dummy function (Andrew Chow)
71d28e7cdc walletdb: Introduce AddRef and RemoveRef functions (Andrew Chow)
27b2766384 walletdb: Move BerkeleyDatabase::Flush(true) to Close() (Andrew Chow)
Pull request description:
A `WalletDatabase` abstract class is created from `BerkeleyDatabase` and is implemented by `BerkeleyDatabase`. First, to get to the point that this is possible, 4 functions need to be added to `BerkeleyDatabase`: `AddRef`, `RemoveRef`, `Open`, and `Close`.
First the increment and decrement of `mapFileUseCount` is refactored into separate functions `AddRef` and `RemoveRef`.
`Open` is introduced as a dummy function. This will raise an exception so that it always fails.
`Close` is refactored from `Flush`. The `shutdown` argument in `Flush` is removed and instead `Flush(true)` is now the `Close` function.
Split from #18971
Requires #19325
ACKs for top commit:
ryanofsky:
Code review ACK d416ae560e. Only changes since last review were rebasing after base PR #19334 merge, and adding cs_db lock in BerkeleyDatabase destructor, which should avoid races accessing env->m_databases and env->m_fileids
fjahr:
Code review ACK d416ae560e
meshcollider:
Code review & test run ACK d416ae560e
Tree-SHA512: 98d05ec093d7446c4488e2b0914584222a331e9a2f4d5be6af98e3f6d78fdd8e75526c12f91a8a52d4820c25bce02aa02aabe92d38bee7eb2fce07d0691b7b0d
9d4b3d86b6