It gets rid of holding state of the io.Reader offset (which is anyways held by
the vfs.FileDescriptor struct. It is also odd using a io.Reader becuase we
using io.ReaderAt to interact with the device. So making a io.ReaderAt wrapper
makes more sense.
Most importantly, it gets rid of the complexity of extracting the file reader
from a regular file implementation and then using it. Now we can just use the
regular file implementation as a reader which is more intuitive.
PiperOrigin-RevId: 260846927
This provides the following benefits:
- We can now use pkg/fd package which does not take ownership
of the file descriptor. So it does not close the fd when garbage collected.
This reduces scope of errors from unexpected garbage collection of io.File.
- It enforces the offset parameter in every read call.
It does not affect the fd offset nor is it affected by it. Hence reducing
scope of error of using stale offsets when reading.
- We do not need to serialize the usage of any global file descriptor anymore.
So this drops the mutual exclusion req hence reducing complexity and
congestion.
PiperOrigin-RevId: 260635174
Ayush Ranjan