c_ares/
ns.rs

1use std::fmt;
2use std::os::raw::{c_int, c_uchar, c_void};
3use std::ptr;
4use std::slice;
5
6use itertools::Itertools;
7
8use crate::error::{Error, Result};
9use crate::hostent::{HasHostent, HostAliasResultsIter, HostentOwned};
10use crate::panic;
11
12/// The result of a successful NS lookup.
13#[derive(Debug)]
14pub struct NSResults {
15    hostent: HostentOwned,
16}
17
18impl NSResults {
19    /// Obtain an `NSResults` from the response to an NS lookup.
20    pub fn parse_from(data: &[u8]) -> Result<NSResults> {
21        let mut hostent: *mut c_types::hostent = ptr::null_mut();
22        let parse_status = unsafe {
23            c_ares_sys::ares_parse_ns_reply(data.as_ptr(), data.len() as c_int, &mut hostent)
24        };
25        if parse_status == c_ares_sys::ares_status_t::ARES_SUCCESS as i32 {
26            let result = NSResults::new(hostent);
27            Ok(result)
28        } else {
29            Err(Error::from(parse_status))
30        }
31    }
32
33    fn new(hostent: *mut c_types::hostent) -> Self {
34        NSResults {
35            hostent: HostentOwned::new(hostent),
36        }
37    }
38
39    /// Returns the hostname from this `NSResults`.
40    pub fn hostname(&self) -> &str {
41        self.hostent.hostname()
42    }
43
44    /// Returns an iterator over the host aliases in this `NSResults`.
45    pub fn aliases(&self) -> HostAliasResultsIter {
46        self.hostent.aliases()
47    }
48}
49
50impl fmt::Display for NSResults {
51    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
52        write!(fmt, "Hostname: {}, ", self.hostname())?;
53        let aliases = self.aliases().format(", ");
54        write!(fmt, "Aliases: [{aliases}]")
55    }
56}
57
58pub(crate) unsafe extern "C" fn query_ns_callback<F>(
59    arg: *mut c_void,
60    status: c_int,
61    _timeouts: c_int,
62    abuf: *mut c_uchar,
63    alen: c_int,
64) where
65    F: FnOnce(Result<NSResults>) + Send + 'static,
66{
67    ares_callback!(arg.cast::<F>(), status, abuf, alen, NSResults::parse_from);
68}
c_ares/ns.rs

c_ares/
ns.rs
