Crate drill_press 

Drill-Press

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 std::io::{Read, Seek, SeekFrom};
use drill_press::*;

if let Ok(mut file) = File::open("README.md") {
    let segments = file.scan_chunks().expect("Unable to scan chunks");
    for segment in segments.data() {
        let start = segment.start;
        let length = segment.end - segment.start;
        file.seek(SeekFrom::Start(start));
        let chunk = (&mut file).take(length);
    }
}

License

Drill-Press is distributed under your choice of the MIT license, or Apache 2.0.

Structs

Segment

Describes the location of a chunk in the file, as well as indicating if it contains data or is a hole

SegmentIter

An iterator over the ranges of a file of a specific SegmentType

Enums

ScanError

Errors returned by scan_chunks

SegmentType

Flag for determining if a segment is a hole, or if it contains data

Traits

Segments

An extention trait to filter segments by Hole or Data segments

SparseFile

An extention trait for File for sparse files