Struct MmapSource 

pub struct MmapSource { /* private fields */ }

Available on crate feature mmap only.

A memory-mapped file source: the kernel pages the file in on access, and data units decode straight from the mapping (no staging copy, no read syscalls). The owned memmap2::Mmap keeps the mapping alive for the reader’s lifetime.

Trait Implementations

impl Debug for MmapSource

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

Formats the value using the given formatter.

impl Source for MmapSource

fn size(&self) -> u64

Total byte length of the source. Fixed for the source’s lifetime and used to reject ranges that run past the end before allocating for them.

fn slice<'a>( &'a mut self, offset: u64, len: usize, _scratch: &'a mut Vec<u8>, ) -> Result<&'a [u8]>

The len bytes at offset, borrowed. In-memory sources return a slice of themselves (zero-copy); a streaming source reads into scratch and returns a slice of that. Errors if the range runs past the source.

fn read_owned(&mut self, offset: u64, len: usize) -> Result<Vec<u8>>

The len bytes at offset in a fresh owned buffer — used where the bytes must outlive the read (the parsed table / ASCII-table backing store). Kept distinct from slice().to_vec() so a streaming source reads straight into the owned buffer (one copy) instead of staging through scratch first (two).