pub async fn peek<'d, S: NorFlash>(
flash: &mut S,
flash_range: Range<u32>,
cache: &mut impl CacheImpl,
data_buffer: &'d mut [u8],
) -> Result<Option<&'d mut [u8]>, Error<S::Error>>Expand description
Peek at the oldest data.
If you also want to remove the data use pop.
The data is written to the given data_buffer and the part that was written is returned.
It is valid to only use the length of the returned slice and use the original data_buffer.
The data_buffer may contain extra data on ranges after the returned slice.
You should not depend on that data.
If the data buffer is not big enough an error is returned.