Struct Null 

pub struct Null { /* private fields */ }

Null storage object.

Reading from this will always return zeroes, writing to it does nothing (except to potentially grow its virtual “file length”).

Implementations

impl Null

pub fn new(size: u64) -> Self

Create a new null storage object with the given initial virtual size.

Trait Implementations

impl Debug for Null

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Null

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Storage for Null

fn size(&self) -> Result<u64>

Storage object length.

async unsafe fn pure_readv( &self, bufv: IoVectorMut<'_>, _offset: u64, ) -> Result<()>

Read data at offset into bufv.

async unsafe fn pure_writev( &self, bufv: IoVector<'_>, offset: u64, ) -> Result<()>

Write data from bufv to offset.

async unsafe fn pure_write_zeroes(&self, offset: u64, length: u64) -> Result<()>

Ensure the given range reads back as zeroes.

async fn flush(&self) -> Result<()>

Flush internal buffers.

async fn sync(&self) -> Result<()>

Sync data already written to the storage hardware.

async unsafe fn invalidate_cache(&self) -> Result<()>

Drop internal buffers.

fn get_storage_helper(&self) -> &CommonStorageHelper

Return the storage helper object (used by the StorageExt implementation).

async fn resize( &self, new_size: u64, _prealloc_mode: PreallocateMode, ) -> Result<()>

Resize to the given size.

async fn open(_opts: StorageOpenOptions) -> Result<Self>

Open a storage object.

fn open_sync(opts: StorageOpenOptions) -> Result<Self>

Available on crate feature sync-wrappers only.

Synchronous wrapper around Storage::open().

async fn create_open(_opts: StorageCreateOptions) -> Result<Self>

Create a storage object and open it.

async fn create(opts: StorageCreateOptions) -> Result<()>

Create a storage object.

fn mem_align(&self) -> usize

Minimum required alignment for memory buffers.

fn req_align(&self) -> usize

Minimum required alignment for offsets and lengths.

fn zero_align(&self) -> usize

Minimum required alignment for zero writes.

fn discard_align(&self) -> usize

Minimum required alignment for effective discards.

fn resolve_relative_path<P: AsRef<Path>>(&self, _relative: P) -> Result<PathBuf>

Resolve the given path relative to this storage object.

fn get_filename(&self) -> Option<PathBuf>

Return a filename, if possible.

async unsafe fn pure_write_allocated_zeroes( &self, offset: u64, length: u64, ) -> Result<()>

Ensure the given range is allocated, and reads back as zeroes.

async unsafe fn pure_discard(&self, _offset: u64, _length: u64) -> Result<()>

Discard the given range, with undefined contents when read back.