The current way were doing it would require copying a 768 character
buffer (part of the Entry struct) to the new element in the vector.
Given it's a plain array, std::move won't eliminate that.
Instead, we can emplace an instance directly into the destination buffer
and then fill it out, avoiding the need to perform any unnecessary
copies.
Given this is done in a loop, we can request the destination to allocate
all of the necessary memory ahead of time, avoiding the need to
potentially keep reallocating over and over on every few insertions into
the vector.
Instead of using an unsigned int as a parameter and expecting a user to
always pass in the correct values, we can just convert the enum into an
enum class and use that type as the parameter type instead, which makes
the interface more type safe.
We also get rid of the bookkeeping "NUM_" element in the enum by just
using an unordered map. This function is generally low-frequency in
terms of calls (and I'd hope so, considering otherwise would mean we're
slamming the disk with IO all the time) so I'd consider this acceptable
in this case.
We can avoid constructing a std::vector here by simply passing a pointer
to the original data and the size of the copy we wish to perform to the
backend's Write() function instead, avoiding copying the data where it's
otherwise not needed.
We were using a second std::vector as a buffer to convert another
std::vector's data into a byte sequence, however we can just use
pointers to the original data and use them directly with WriteBuffer,
which avoids copying the data at all into a separate std::vector.
We simply cast the pointers to u8* (which is allowed by the standard,
given std::uint8_t is an alias for unsigned char on platforms that we
support).
Previously we were just copying the data whole-sale, even if the length
was less than the total data size. This effectively makes the
actual_data vector useless, which is likely not intended.
Instead, amend this to only copy the given length amount of data.
At the same time, we can avoid zeroing out the data before using it by
passing iterators to the constructor instead of a size.
* Add VfsFile and VfsDirectory classes
* Finish abstract Vfs classes
* Implement RealVfsFile (computer fs backend)
* Finish RealVfsFile and RealVfsDirectory
* Finished OffsetVfsFile
* More changes
* Fix import paths
* Major refactor
* Remove double const
* Use experimental/filesystem or filesystem depending on compiler
* Port partition_filesystem
* More changes
* More Overhaul
* FSP_SRV fixes
* Fixes and testing
* Try to get filesystem to compile
* Filesystem on linux
* Remove std::filesystem and document/test
* Compile fixes
* Missing include
* Bug fixes
* Fixes
* Rename v_file and v_dir
* clang-format fix
* Rename NGLOG_* to LOG_*
* Most review changes
* Fix TODO
* Guess 'main' to be Directory by filename
This makes the formatting expectations more obvious (e.g. any zero padding specified
is padding that's entirely dedicated to the value being printed, not any pretty-printing
that also gets tacked on).
