1 // Copyright 2013 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
13 Synchronous DNS Resolution
15 Contains the functionality to perform DNS resolution in a style related to
20 #![allow(missing_doc)]
23 use io::net::ip::{SocketAddr, IpAddr};
24 use option::{Option, Some, None};
25 use rt::rtio::{IoFactory, LocalIo};
26 use slice::ImmutableVector;
28 /// Hints to the types of sockets that are desired when looking up hosts
33 /// Flags which can be or'd into the `flags` field of a `Hint`. These are used
34 /// to manipulate how a query is performed.
36 /// The meaning of each of these flags can be found with `man -s 3 getaddrinfo`
47 /// A transport protocol associated with either a hint or a return value of
53 /// This structure is used to provide hints when fetching addresses for a
54 /// remote host to control how the lookup is performed.
56 /// For details on these fields, see their corresponding definitions via
57 /// `man -s 3 getaddrinfo`
60 socktype: Option<SocketType>,
61 protocol: Option<Protocol>,
68 socktype: Option<SocketType>,
69 protocol: Option<Protocol>,
73 /// Easy name resolution. Given a hostname, returns the list of IP addresses for
75 pub fn get_host_addresses(host: &str) -> IoResult<~[IpAddr]> {
76 lookup(Some(host), None, None).map(|a| a.map(|i| i.address.ip))
79 /// Full-fleged resolution. This function will perform a synchronous call to
80 /// getaddrinfo, controlled by the parameters
84 /// * hostname - an optional hostname to lookup against
85 /// * servname - an optional service name, listed in the system services
86 /// * hint - see the hint structure, and "man -s 3 getaddrinfo", for how this
89 /// FIXME: this is not public because the `Hint` structure is not ready for public
90 /// consumption just yet.
91 fn lookup(hostname: Option<&str>, servname: Option<&str>, hint: Option<Hint>)
92 -> IoResult<~[Info]> {
93 LocalIo::maybe_raise(|io| io.get_host_addresses(hostname, servname, hint))
96 // Ignored on android since we cannot give tcp/ip
97 // permission without help of apk
98 #[cfg(test, not(target_os = "android"))]
100 iotest!(fn dns_smoke_test() {
101 let ipaddrs = get_host_addresses("localhost").unwrap();
102 let mut found_local = false;
103 let local_addr = &Ipv4Addr(127, 0, 0, 1);
104 for addr in ipaddrs.iter() {
105 found_local = found_local || addr == local_addr;
107 assert!(found_local);
110 iotest!(fn issue_10663() {
111 // Something should happen here, but this certainly shouldn't cause
112 // everything to die. The actual outcome we don't care too much about.
113 get_host_addresses("example.com").unwrap();