Function get_lock_state

block/src/fcntl.rs:236–254

Returns the current lock state using [`fcntl`] with respect to the given parameters. # Parameters - `file`: The file for which to get the lock state. - `granularity`: The [`LockGranularity`].

(
    file: &Fd,
    granularity: LockGranularity,
)

/// - `file`: The file for which to get the lock state.
/// - `granularity`: The [`LockGranularity`].
pub fn get_lock_state<Fd: AsRawFd>(
    file: &Fd,
    granularity: LockGranularity,
) -> Result<LockState, LockError> {
    let mut flock = get_flock(LockType::Write, granularity);
    let res = fcntl(file.as_raw_fd(), FcntlArg::F_OFD_GETLK(&mut flock));
    match res {
        0 => {
            let state = flock.l_type as libc::c_int;
            let state = LockState::new(state);
            Ok(state)
        }
        -1 => {
            let io_error = io::Error::last_os_error();
            Err(LockError::Io(io_error))
        }
        val => panic!("Unexpected return value from fcntl(): {val}"),
    }
}