Use LRU cache for ESMReaders. When cache capacity is reached close least
recently used ESMReader. Remember the file name if a reader was open. Once the
reader requested again open the file if there is stored name for it. Put
released ESMReader to the back of the free items list. Close ESMReader's from
the front of the free items list.
Cached item can be used only by one client at the same time. If the same item is
requested twice exception is thrown. This should never happen in practice. If
this happens need to fix the client logic.
It's allowed to go over the capacity limit when requesting different readers.
Ideally this should never happen but there will be system error anyway
signalizing about too many open files. Need to fix client logic in this case.
All places that were using a vector of ESMReaders now using the cache. Cache is
local for each use case and there is no need for a thread safety.
This PR aims to start addressing `ESM` design issues that have silenced errors we incorporated into groundcover `ESM` loading approaches.
- We move the resolution of `parentFileIndices` from `ESMStore` to `ESMReader` as suggested in a `TODO` comment.
- We improve a highly misleading comment which downplayed the significance of `parentFileIndices`.
- We document important preconditions.
- We move a user facing error message to the highest level and improve its context.
- We remove an inappropriate `setGlobalReaderList` method. We now pass this reader list into the method that requires it.
- We remove a thoroughly pointless optimisation of `Store<ESM::LandTexture>`'s construction that has unnecessarily depended on `getGlobalReaderList`.
There should be no functional changes for `master`, but this PR should remove an issue blocking PR #3208.
A component to load ESM content files with limited support for record types and
selection which of them to load. Supported record types are:
ACTI, CELL, CONT, DOOR, GMST, LAND, STAT.
