Struct mla::layers::compress::CompressionLayerWriter

pub struct CompressionLayerWriter<'a, W: 'a + Write> { /* fields omitted */ }

Compression layer is made of independent CompressedBlock, ending by an index for seekable accesses [CompressedBlock][CompressedBlock]...[CompressedBlock][Index]

Compression is made of nested independent compressed block of a fixed uncompressed size Pro:

• no need to store the compressed size
• compression can be streamed (storing the compressed size before the compressed block leads to either seekable stream, which is not an option here, or full-memory compression before actual write, which add limits to the memory footprint) Cons:
• if the index is lost, a slow decompression with a block size of 1 is needed to found the CompressedBlock boundaries

Implementations

impl<'a, W: 'a + Write> CompressionLayerWriter<'a, W>

pub fn new(
    inner: Box<dyn LayerWriter<'a, W> + 'a>,
    config: &CompressionConfig
) -> CompressionLayerWriter<'a, W>

Trait Implementations

impl<'a, W: 'a + Write> LayerWriter<'a, W> for CompressionLayerWriter<'a, W>

fn into_inner(self) -> Option<Box<dyn LayerWriter<'a, W> + 'a>>

Unwraps the inner writer

fn into_raw(self: Box<Self>) -> W

Unwraps the original I/O writer

fn finalize(&mut self) -> Result<(), Error>

Finalize the current layer, like adding the footer.

impl<'a, W: 'a + Write> Write for CompressionLayerWriter<'a, W>

fn write(&mut self, buf: &[u8]) -> Result<usize>

Write a buffer into this writer, returning how many bytes were written.

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

Flush this output stream, ensuring that all intermediately buffered contents reach their destination.

fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers.

fn is_write_vectored(&self) -> bool

🔬 This is a nightly-only experimental API. (can_vector)

Determines if this Writeer has an efficient write_vectored implementation.

fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>

Attempts to write an entire buffer into this writer.

fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>

🔬 This is a nightly-only experimental API. (write_all_vectored)

Attempts to write multiple buffers into this writer.

fn write_fmt(&mut self, fmt: Arguments<'_>) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

fn by_ref(&mut self) -> &mut Self

Creates a "by reference" adaptor for this instance of Write.