Struct ChecksumWriter 

pub struct ChecksumWriter<C, W>
where
    C: CodeqConfig,
{ /* private fields */ }

A writer that calculates CRC32 checksum while writing data.

This writer wraps any type implementing io::Write and transparently calculates a CRC32 checksum of all data written through it. The checksum can be either:

• Retrieved using finalize_checksum()
• Written to the underlying writer using write_checksum()

Example:

use codeq::ChecksumWriter;
use codeq::config::Crc32fast;

let mut writer = ChecksumWriter::<Crc32fast,_>::new(Vec::new());
writer.write_all(b"hello").unwrap();
let checksum = writer.finalize_checksum();
assert_eq!(checksum, crc32fast::hash(b"hello") as u64);

Create a new writer with ChecksumWriter::new or CodeqConfig::new_writer, for example:

let writer = Crc32fast::new_writer(Vec::new());

Implementations

impl<C, W> ChecksumWriter<C, W>

where C: CodeqConfig, W: Write,

pub fn new(inner: W) -> Self

Create a new ChecksumWriter that wraps the provided writer.

pub fn finalize_checksum(self) -> u64

Finalize the crc32 checksum and consume self.

Return the checksum of all written data.

pub fn write_checksum(self) -> Result<usize>

Append the finalized crc32 checksum in the least significant 32 bits of a u64 to the its inner writer, in BigEndian.

Returns the number of bytes written.

Trait Implementations

impl<C, W> Write for ChecksumWriter<C, W>

where C: CodeqConfig, W: Write,

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

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

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

Flushes 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 Writer 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, args: Arguments<'_>) -> Result<(), Error>

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

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

where Self: Sized,

Creates a “by reference” adapter for this instance of Write.