Struct uu_tail::chunks::BytesChunkBuffer

pub struct BytesChunkBuffer { /* private fields */ }

An abstraction layer on top of BytesChunk mainly to simplify filling only the needed amount of chunks. See also Self::fill.

Implementations

impl BytesChunkBuffer

pub fn new(num_print: u64) -> Self

Creates a new BytesChunkBuffer.

Arguments

• num_print: The number of bytes to print

Examples

let mut chunk = BytesChunk::new();
chunk.buffer[1] = 1;
chunk.bytes = 2;
let new_chunk = BytesChunk::from_chunk(&chunk, 0);
assert_eq!(2, new_chunk.get_buffer().len());
assert_eq!(&[0, 1], new_chunk.get_buffer());

let new_chunk = BytesChunk::from_chunk(&chunk, 1);
assert_eq!(1, new_chunk.get_buffer().len());
assert_eq!(&[1], new_chunk.get_buffer());

pub fn fill(&mut self, reader: &mut impl BufRead) -> UResult<()>

Fills this buffer with chunks and consumes the reader completely. This method ensures that there are exactly as many chunks as needed to match self.num_print bytes, so there are in sum exactly self.num_print bytes stored in all chunks. The method returns an iterator over these chunks. If there are no chunks, for example because the piped stdin contained no bytes, or num_print = 0 then iterator.next returns None.

Examples

use crate::chunks::BytesChunkBuffer;
use std::io::{BufReader, Cursor};

let mut reader = BufReader::new(Cursor::new(""));
let num_print = 0;
let mut chunks = BytesChunkBuffer::new(num_print);
chunks.fill(&mut reader).unwrap();

let mut reader = BufReader::new(Cursor::new("a"));
let num_print = 1;
let mut chunks = BytesChunkBuffer::new(num_print);
chunks.fill(&mut reader).unwrap();

pub fn print(&self, writer: impl Write) -> UResult<()>

pub fn has_data(&self) -> bool