This is an extraction of ArgsManager related functions from util/system
into their own common file.
Config file related functions are moved to common/config.cpp.
The background of this commit is an ongoing effort to decouple the
libbitcoinkernel library from the ArgsManager. The ArgsManager belongs
into the common library, since the kernel library should not depend on
it. See doc/design/libraries.md for more information on this rationale.
The fs.* files are already part of the libbitcoin_util library. With the
introduction of the fs_helpers.* it makes sense to move fs.* into the
util/ directory as well.
Add functionality for activating a snapshot-based chainstate if one is
detected on-disk.
Also cautiously initialize chainstate cache usages so that we don't
somehow blow past our cache allowances during initialization, then
rebalance at the end of init.
Co-authored-by: Russell Yanofsky <russ@yanofsky.org>
This changes the snapshot's leveldb chainstate dir name from
`chainstate_[blockhash]` to `chainstate_snapshot`. This simplifies
later logic that loads snapshot data, and enforces the limitation
of a single snapshot at any given time.
Since we still need to persis the blockhash of the base block, we
write that out to a file (`chainstate_snapshot/base_blockhash`) for
later use during initialization, so that we can reinitialize the
snapshot chainstate.
Co-authored-by: Russell Yanofsky <russ@yanofsky.org>