hole-punch 0.0.3

A WIP cross platform library for extracting information about holes in sparse files.
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Hole-Punch
==========

![Crates.io](https://img.shields.io/crates/v/hole-punch?style=flat-square&logo=rust) ![License](https://img.shields.io/crates/l/hole-punch?style=flat-square) ![Unsafe](https://img.shields.io/badge/unsafe-very%20yes-important?style=flat-square) ![Maintenance](https://img.shields.io/maintenance/yes/2020?style=flat-square)

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

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

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
-----

```rust
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 segment {
    if let SegmentType::Data = segment.segment_type {
        let start = segment.start;
        let end = segment.end;

        let length = end - start;
        do_something_with_data(&mut file, start, length);
    }
}
```

License
-------

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

TO-DOs
------

The following features are on my "to implement" list, in order of importance:

1.	Windows support
2.	Fallback mode (reading the entire file manually looking for chunks of 0s)