#cross-platform #sparse #manipulating #listing #scan #chunks #holes

bin+lib drill-press

A cross platform library for listing and manipulating holes in sparse files

2 releases

0.1.1 Sep 16, 2022
0.1.0 Feb 16, 2022

#482 in Operating systems

MIT/Apache

26KB
518 lines

Hole-Punch

Crates.io License Unsafe Maintenance

A simple, cross platform crate for finding the locations of holes in sparse files.

Forked from Nathan McCarty's hole_punch (git)

Currently supports Unix-like platforms that support the SEEK_HOLE and SEEK_DATA commands on lseek, as well as windows.

The operating systems that currently support filesystem-level sparsity information are:

  1. Linux
  2. Android
  3. FreeBSD
  4. Windows
  5. MacOS

These are currently implemented with a compile time switch, and SparseFile::scan_chunks will always immediately return with a ScanError::UnsupportedPlatform error on platforms not on this list.

Usage

use std::fs::File;
use hole_punch::*;

let mut file = File::open("a big sparse file");
let segments = file.scan_chunks().expect("Unable to scan chunks");
for segment in segments {
    if SegmentType::Data == segment.segment_type {
        let start = segment.start();
        let length = segment.len();
        do_something_with_data(&mut file, start, length);
    }
}

License

Hole-Punch is distributed under your choice of the MIT license, or Apache 2.0.

Dependencies

~0.3–1MB
~20K SLoC