floss: Remove unnecessary regex crate usage

nix = "0.23"

num-traits = "0.2"

protobuf = "2.0"

regex = "1.5"

serde_json = "1.0"

syslog = "6"

tokio = { version = "1.0", features = ["fs", "macros", "rt-multi-thread", "sync"] }

use log::{debug, error, info, warn};

use nix::sys::signal::{self, Signal};

use nix::unistd::Pid;

use regex::Regex;

use std::collections::{BTreeMap, HashMap};

use std::convert::TryFrom;

use std::fmt::{Display, Formatter};

/// Given an pid path, returns the adapter index for that pid path.

fn get_hci_index_from_pid_path(path: &str) -> Option<VirtualHciIndex> {

    let re = Regex::new(r"bluetooth([0-9]+).pid").unwrap();

    re.captures(path)?.get(1)?.as_str().parse().ok().map(VirtualHciIndex)

    path.rsplit_once('/')

        .and_then(|tup| tup.1.strip_prefix("bluetooth"))

        .and_then(|s| s.strip_suffix(".pid"))

        .and_then(|p| p.parse::<i32>().ok())

        .map(VirtualHciIndex)

}

fn event_name_to_string(name: Option<&std::ffi::OsStr>) -> Option<String> {

            Some(VirtualHciIndex(10))

        );

        assert_eq!(get_hci_index_from_pid_path("/var/run/bluetooth/garbage"), None);

        assert_eq!(get_hci_index_from_pid_path("garbage"), None);

    }

}