nom_http.rs

#[macro_use]
extern crate nom;

use nom::IResult;

use std::env;
use std::fs::File;

#[derive(Debug)]
struct Request<'a> {
    method:  &'a [u8],
    uri:     &'a [u8],
    version: &'a [u8],
}

#[derive(Debug)]
struct Header<'a> {
    name:  &'a [u8],
    value: Vec<&'a [u8]>,
}

fn is_token(c: u8) -> bool {
    match c {
        128...255 => false,
        0...31    => false,
        b'('      => false,
        b')'      => false,
        b'<'      => false,
        b'>'      => false,
        b'@'      => false,
        b','      => false,
        b';'      => false,
        b':'      => false,
        b'\\'     => false,
        b'"'      => false,
        b'/'      => false,
        b'['      => false,
        b']'      => false,
        b'?'      => false,
        b'='      => false,
        b'{'      => false,
        b'}'      => false,
        b' '      => false,
        _         => true,
    }
}

fn not_line_ending(c: u8) -> bool {
    c != b'\r' && c != b'\n'
}

fn is_space(c: u8) -> bool {
    c == b' '
}

fn is_not_space(c: u8)        -> bool { c != b' ' }
fn is_horizontal_space(c: u8) -> bool { c == b' ' || c == b'\t' }

fn is_version(c: u8) -> bool {
    c >= b'0' && c <= b'9' || c == b'.'
}

named!(line_ending, alt!(tag!("\n") | tag!("\r\n")));

named!(request_line(&[u8]) -> Request, chain!(
    method: take_while1!(is_token)     ~
            take_while1!(is_space)     ~
    url:    take_while1!(is_not_space) ~
            take_while1!(is_space)     ~
    version: http_version              ~
    line_ending,

    || Request {
        method: method,
        uri:    url,
        version: version,
    }));

named!(http_version, chain!(
    tag!("HTTP/")                    ~
    version: take_while1!(is_version),

    || version));

named!(message_header_value, chain!(
          take_while1!(is_horizontal_space) ~
    data: take_while1!(not_line_ending)     ~
    line_ending,

    || data));

named!(message_header(&[u8]) -> Header, chain!(
    name:   take_while1!(is_token) ~
            char!(':') ~
    values: many1!(message_header_value),

    || Header {
        name: name,
        value: values,
    }));

named!(request(&[u8]) -> (Request, Vec<Header>), chain!(
    req: request_line           ~
    h:   many1!(message_header) ~
         line_ending,

    || (req, h)));

fn main() {
    let mut contents: Vec<u8> = Vec::new();

    {
        use std::io::Read;

        let mut file = File::open(env::args().nth(1).expect("File to read")).ok().expect("Failed to open file");

        let _ = file.read_to_end(&mut contents).unwrap();
    }

    let mut buf = &contents[..];
    let mut i   = 0;

    loop {
        match request(buf) {
            IResult::Done(b, _) => {
                buf = b;

                i = i + 1;

                if b.is_empty() {
                    break;
                }
            },
            IResult::Error(e) => panic!("{:?}", e),
            IResult::Incomplete(_) => panic!("Incomplete!"),
        }
    }

    println!("{}", i);
}