bgzf_bufgzi_inspect.rs

//! Prints the compressed-uncompressed position pairs of a GZ index.

//! Unmodified from:
//! https://github.com/zaeleus/noodles/blob/master/noodles-bgzf/examples/bgzf_gzi_inspect.rs

use std::{env, io, fs};

use std::io::prelude::*;
use std::io::BufReader;
use std::fs::File;

use noodles_bgzf::gzi;

fn buf_read(src: String) -> io::Result<gzi::Index> {
    let file_size = fs::metadata(src.clone()).expect("could not get file meta data").len() as usize;
    let buf_size = file_size/8;
    
    let file = File::open(src).expect("failed to open file");
    let mut buf_reader = BufReader::new(&file);

    let mut buffer = Vec::with_capacity(buf_size);
    buf_reader.read_to_end(&mut buffer)?;
    let mut reader = gzi::Reader::new(&buffer[..]);

    reader.read_index()
}

fn main() -> io::Result<()> {
    let src = env::args().nth(1).expect("missing src");

    let index = buf_read(src)?;

    for record in &index {
        println!("{}\t{}", record.0, record.1);
    }


    Ok(())
}