bytecmp
====

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`bytecmp` is a simple crate which offers data comparison mechanisms which go beyond the simple 
equality. It only operates on byte slices, hence its name, and relies on efficiently finding 
 common substrings between two blob of data. The implementation relies on two different linear 
 time algorithms: a `HashMap` based algorithm called `HashMatch` and 
 a suffix tree built using Ukkonen algorithm called `TreeMatch`.

`bytecmp` is a fork of [haxelion/bcmp](https://github.com/haxelion/bcmp).


Examples
--------

Iterate over the matches between two strings using `HashMatch` with a 
minimum match length of 2 bytes:

``` rust
extern crate bytecmp;

use bytecmp::{AlgoSpec, MatchIterator};

fn main() {
    let a = "abcdefg";
    let b = "012abc34cdef56efg78abcdefg";
    let match_iter = MatchIterator::new(a.as_bytes(), b.as_bytes(), AlgoSpec::HashMatch(2));
    for m in match_iter {
        println!("Match: {:}", &a[m.first_pos..m.first_end()]);
    }
}
```

Construct a patch set to build the file `b` from the file `a` using `TreeMatch`
with a minimum match length of 4 bytes:

``` rust
extern crate bytecmp;

use std::fs::File;
use std::io::Read;

use bytecmp::{AlgoSpec, patch_set};

fn main() {
    let mut a = Vec::<u8>::new();
    let mut b = Vec::<u8>::new();
    File::open("a").unwrap().read_to_end(&mut a);
    File::open("b").unwrap().read_to_end(&mut b);

    let ps = patch_set(&a, &b, AlgoSpec::TreeMatch(4));
    for patch in ps {
        println!("b[0x{:x}..0x{:x}] == a[0x{:x}..0x{:x}]", patch.second_pos, patch.second_end(), patch.first_pos, patch.first_end());
    }
}
```