The current WiiSave code is extremely messy, as it exposes all kinds of
implementation details in the header (including internal struct
definitions and magic numbers that don't have to be).
The read/write code is intermingled, so it's hard to tell which members
are used, or when/where they are set at all.
It also implicitly relies on some functions being called in a specific
order since it doesn't seek manually every time, which makes the code
even more fragile.
The logic is also hardcoded to only support bin->nand or nand->bin,
even though it would be useful to support nand->nand (for the
Movie save copying code, for example).
This commit attempts to solve these problems by getting rid of the
WiiSave class:
* Read/write code is moved to new Storage classes (NandStorage and
DataBinStorage) with small, clear functions that do one and only
one thing.
* The import/export logic was refactored into a generic Copy function
that takes two storages as parameters.
* The existing import and export functions are now just small wrappers
that call Copy with the appropriate storages.
This makes it easier to generate random numbers or fill a buffer with
random data in a cryptographically secure way.
This also replaces existing usages of RNG functions in the codebase:
* <random> is pretty hard to use correctly, and std::random_device does
not give enough guarantees about its results (it's
implementation-defined, non cryptographically secure and could be
deterministic on some platforms).
Doing things correctly is error prone and verbose.
* rand() is terrible and should not be used especially in crypto code.
Normalizes variable names to conform to our coding conventions.
Previously we were signifying some variables as externally linked
globals, which wasn't the case.
The definition of the function uses the ordering {mod, reg, rm}, which
is correct. Match the prototype to this, so that the parameter list
isn't misleading.
We can just use std::any_of here to collapse the checking code down to a
single assignment as opposed to a loop. This also slightly improves on
the existing code, as this won't continue to iterate through the cluster
metadata if an entry that's non-zero is encountered.
Pretty much all of the source files contain the following:
namespace IOS
{
namespace HLE
{
namespace <name>
{
// actual code here
} // namespace <name>
} // namespace HLE
} // namespace IOS
which is really verbose boilerplate, because most of the files inside
of Core/IOS are for IOS HLE.
This commit replaces that with a more concise `namespace IOS::HLE`
or `namespace IOS::HLE::(name)`.
This is just used as a means of carting around routines. It's not meant
to directly have functionality embedded within it--this is the job of
the inheriting data structure--so we can just make this a basic struct.
Particularly given all the data members were public to begin with.
Léo Lam