Bad writing data method used in File::write_at_sync

[ikopylov]

It uses write_at which does not guarantee that all passed data will be written. Instead write_all_at should be used (https://doc.rust-lang.org/std/os/unix/fs/trait.FileExt.html#method.write_all_at)

https://github.com/qoollo/pearl/blob/master/src/blob/file.rs#L96

[ikopylov]

Same for read: read_at should be replaced with read_exact_at: https://github.com/qoollo/pearl/blob/master/src/blob/file.rs#L118

read_to_end should be used inside read_all: https://github.com/qoollo/pearl/blob/master/src/blob/file.rs#L101