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extern crate thiserror;
use thiserror::Error;
#[derive(Error, Debug)]
pub enum CttyError {
#[error("Controlling TTY for this process not found")]
NotFound,
#[error("System returned invalid data when looking up CTTY")]
SystemDataParseFailure,
#[error("Failed to request CTTY information from system")]
SystemPermissionFailure,
#[error(transparent)]
IOError(#[from] std::io::Error)
}
#[cfg(target_os = "linux")]
mod linux {
use std::fs::File;
use std::io::prelude::*;
use ::CttyError;
extern crate glob;
use self::glob::glob;
extern crate nix;
use self::nix::sys::stat::stat;
pub fn get_ctty_dev() -> Result<u64, CttyError> {
let mut stat_f = File::open("/proc/self/stat")?;
let mut stat = String::new();
stat_f.read_to_string(&mut stat)?;
let mut start_idx = stat.rfind(')').unwrap_or(0);
if start_idx == 0 {
return Err(CttyError::SystemDataParseFailure);
}
start_idx += 2;
let values_str = &stat[start_idx..];
let mut values = values_str.split_whitespace();
let dev = values.nth(4).ok_or(CttyError::SystemDataParseFailure)?;
let dev_int = dev.parse::<i32>().map_err(|_| CttyError::SystemDataParseFailure)?;
Ok(dev_int as u64)
}
pub fn get_path_for_dev(dev: u64) -> Result<String, CttyError> {
let patterns = ["/dev/pts/*", "/dev/tty"];
for i in 0..patterns.len() {
for entry in glob(patterns[i]).unwrap() {
let path = match entry {
Ok(p) => p,
Err(_) => {
continue;
}
};
let stat = match stat(&path) {
Ok(s) => s,
Err(_) => {
continue;
}
};
if dev == stat.st_rdev {
return Ok(String::from(path.to_str().unwrap()));
}
}
}
Err(CttyError::NotFound)
}
}
#[cfg(target_os = "linux")]
pub use linux::*;
#[cfg(any(target_os = "freebsd", target_os = "macos"))]
mod bsd {
use std::ffi::CStr;
use ::CttyError;
extern crate libc;
use self::libc::{S_IFCHR, c_int, mode_t, dev_t, c_char};
extern "C" {
fn _get_ctty_dev() -> u64;
fn devname_r(dev: dev_t, type_: mode_t, buf: *mut u8, len: c_int) -> *mut c_char;
}
pub fn get_ctty_dev() -> Result<u64, CttyError> {
let res = unsafe { _get_ctty_dev() };
if res == 0 {
return Err(CttyError::NotFound);
}
Ok(res)
}
pub fn get_path_for_dev(dev: u64) -> Result<String, CttyError> {
let mut buf: Vec<u8> = Vec::with_capacity(255);
unsafe {
let res: *mut c_char = devname_r(dev as dev_t, S_IFCHR, buf.as_mut_ptr(), 255);
if res.is_null() || *res as u8 == b'?' || *res as u8 == b'#' {
return Err(CttyError::NotFound);
}
let res_owned = CStr::from_ptr(res).to_string_lossy().into_owned();
Ok(format!("{}{}", "/dev/", res_owned))
}
}
}
#[cfg(any(target_os = "freebsd", target_os = "macos"))]
pub use bsd::*;
#[cfg(test)]
mod tests {
use std::error::Error;
use ::get_path_for_dev;
use ::get_ctty_dev;
#[test]
fn test_get_ctty_dev() -> Result<(), Box<dyn Error>> {
let dev = get_ctty_dev().unwrap();
dbg!(dev);
let path = get_path_for_dev(dev)?;
dbg!(path);
Ok(())
}
}