Instead of returning a raw pointer, which could be technically invalid
when using it in the caller function, we return a valid RefPtr of such
device.
This ensures that the code in DevPtsFS is now safe from a rare race
condition in which the SlavePTY device is gone but we still have a
pointer to it.
SysFS, ProcFS and DevPtsFS were all sending filetype 0 when traversing
their directories, but it is actually very easy to send proper filetypes
in these filesystems.
This patch binds all RAM backed filesystems to use only one enum for
their internal filetype, to simplify the implementation and allow
sharing of code.
Please note that the Plan9FS case is currently not solved as I am not
familiar with this filesystem and its constructs.
The ProcFS mostly keeps track of the filetype, and a fix was needed for
the /proc root directory - all processes exhibit a directory inside it
which makes it very easy to hardcode the directory filetype for them.
There's also the `self` symlink inode which is now exposed as DT_LNK.
As for SysFS, we could leverage the fact everything inherits from the
SysFSComponent class, so we could have a virtual const method to return
the proper filetype.
Most of the files in SysFS are "regular" files though, so the base class
has a non-pure virtual method.
Lastly, the DevPtsFS simply hardcodes '.' and '..' as directory file
type, and everything else is hardcoded to send the character device file
type, as this filesystem is only exposing character pts device files.
In a bunch of cases, this actually ends up simplifying the code as
to_number will handle something such as:
```
Optional<I> opt;
if constexpr (IsSigned<I>)
opt = view.to_int<I>();
else
opt = view.to_uint<I>();
```
For us.
The main goal here however is to have a single generic number conversion
API between all of the String classes.
"Wherever applicable" = most places, actually :^), especially for
networking and filesystem timestamps.
This includes changes to unzip, which uses DOSPackedTime, since that is
changed for the FAT file systems.
That's what this class really is; in fact that's what the first line of
the comment says it is.
This commit does not rename the main files, since those will contain
other time-related classes in a little bit.
Because the ".." entry in a directory is a separate inode, if a
directory is renamed to a new location, then we should update this entry
the point to the new parent directory as well.
Co-authored-by: Liav A <liavalb@gmail.com>