src/libstd/sys_common/net.rs

   1 // Copyright 2013-2014 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.
   4 //
   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.
  10
  11 use cmp;
  12 use ffi::CString;
  13 use fmt;
  14 use io::{self, Error, ErrorKind};
  15 use libc::{c_int, c_void};
  16 use mem;
  17 use net::{SocketAddr, Shutdown, Ipv4Addr, Ipv6Addr};
  18 use ptr;
  19 use sys::net::{cvt, cvt_r, cvt_gai, Socket, init, wrlen_t};
  20 use sys::net::netc as c;
  21 use sys_common::{AsInner, FromInner, IntoInner};
  22 use time::Duration;
  23
  24 #[cfg(any(target_os = "dragonfly", target_os = "freebsd",
  25           target_os = "ios", target_os = "macos",
  26           target_os = "openbsd", target_os = "netbsd",
  27           target_os = "solaris", target_os = "haiku"))]
  28 use sys::net::netc::IPV6_JOIN_GROUP as IPV6_ADD_MEMBERSHIP;
  29 #[cfg(not(any(target_os = "dragonfly", target_os = "freebsd",
  30               target_os = "ios", target_os = "macos",
  31               target_os = "openbsd", target_os = "netbsd",
  32               target_os = "solaris", target_os = "haiku")))]
  33 use sys::net::netc::IPV6_ADD_MEMBERSHIP;
  34 #[cfg(any(target_os = "dragonfly", target_os = "freebsd",
  35           target_os = "ios", target_os = "macos",
  36           target_os = "openbsd", target_os = "netbsd",
  37           target_os = "solaris", target_os = "haiku"))]
  38 use sys::net::netc::IPV6_LEAVE_GROUP as IPV6_DROP_MEMBERSHIP;
  39 #[cfg(not(any(target_os = "dragonfly", target_os = "freebsd",
  40               target_os = "ios", target_os = "macos",
  41               target_os = "openbsd", target_os = "netbsd",
  42               target_os = "solaris", target_os = "haiku")))]
  43 use sys::net::netc::IPV6_DROP_MEMBERSHIP;
  44
  45 #[cfg(any(target_os = "linux", target_os = "android",
  46           target_os = "dragonfly", target_os = "freebsd",
  47           target_os = "openbsd", target_os = "netbsd",
  48           target_os = "haiku", target_os = "bitrig"))]
  49 use libc::MSG_NOSIGNAL;
  50 #[cfg(not(any(target_os = "linux", target_os = "android",
  51               target_os = "dragonfly", target_os = "freebsd",
  52               target_os = "openbsd", target_os = "netbsd",
  53               target_os = "haiku", target_os = "bitrig")))]
  54 const MSG_NOSIGNAL: c_int = 0x0;
  55
  56 ////////////////////////////////////////////////////////////////////////////////
  57 // sockaddr and misc bindings
  58 ////////////////////////////////////////////////////////////////////////////////
  59
  60 pub fn setsockopt<T>(sock: &Socket, opt: c_int, val: c_int,
  61                      payload: T) -> io::Result<()> {
  62     unsafe {
  63         let payload = &payload as *const T as *const c_void;
  64         cvt(c::setsockopt(*sock.as_inner(), opt, val, payload,
  65                           mem::size_of::<T>() as c::socklen_t))?;
  66         Ok(())
  67     }
  68 }
  69
  70 pub fn getsockopt<T: Copy>(sock: &Socket, opt: c_int,
  71                        val: c_int) -> io::Result<T> {
  72     unsafe {
  73         let mut slot: T = mem::zeroed();
  74         let mut len = mem::size_of::<T>() as c::socklen_t;
  75         cvt(c::getsockopt(*sock.as_inner(), opt, val,
  76                           &mut slot as *mut _ as *mut _,
  77                           &mut len))?;
  78         assert_eq!(len as usize, mem::size_of::<T>());
  79         Ok(slot)
  80     }
  81 }
  82
  83 fn sockname<F>(f: F) -> io::Result<SocketAddr>
  84     where F: FnOnce(*mut c::sockaddr, *mut c::socklen_t) -> c_int
  85 {
  86     unsafe {
  87         let mut storage: c::sockaddr_storage = mem::zeroed();
  88         let mut len = mem::size_of_val(&storage) as c::socklen_t;
  89         cvt(f(&mut storage as *mut _ as *mut _, &mut len))?;
  90         sockaddr_to_addr(&storage, len as usize)
  91     }
  92 }
  93
  94 pub fn sockaddr_to_addr(storage: &c::sockaddr_storage,
  95                     len: usize) -> io::Result<SocketAddr> {
  96     match storage.ss_family as c_int {
  97         c::AF_INET => {
  98             assert!(len as usize >= mem::size_of::<c::sockaddr_in>());
  99             Ok(SocketAddr::V4(FromInner::from_inner(unsafe {
 100                 *(storage as *const _ as *const c::sockaddr_in)
 101             })))
 102         }
 103         c::AF_INET6 => {
 104             assert!(len as usize >= mem::size_of::<c::sockaddr_in6>());
 105             Ok(SocketAddr::V6(FromInner::from_inner(unsafe {
 106                 *(storage as *const _ as *const c::sockaddr_in6)
 107             })))
 108         }
 109         _ => {
 110             Err(Error::new(ErrorKind::InvalidInput, "invalid argument"))
 111         }
 112     }
 113 }
 114
 115 #[cfg(target_os = "android")]
 116 fn to_ipv6mr_interface(value: u32) -> c_int {
 117     value as c_int
 118 }
 119
 120 #[cfg(not(target_os = "android"))]
 121 fn to_ipv6mr_interface(value: u32) -> ::libc::c_uint {
 122     value as ::libc::c_uint
 123 }
 124
 125 ////////////////////////////////////////////////////////////////////////////////
 126 // get_host_addresses
 127 ////////////////////////////////////////////////////////////////////////////////
 128
 129 pub struct LookupHost {
 130     original: *mut c::addrinfo,
 131     cur: *mut c::addrinfo,
 132 }
 133
 134 impl Iterator for LookupHost {
 135     type Item = SocketAddr;
 136     fn next(&mut self) -> Option<SocketAddr> {
 137         loop {
 138             unsafe {
 139                 let cur = match self.cur.as_ref() {
 140                     None => return None,
 141                     Some(c) => c,
 142                 };
 143                 self.cur = cur.ai_next;
 144                 match sockaddr_to_addr(mem::transmute(cur.ai_addr),
 145                                        cur.ai_addrlen as usize)
 146                 {
 147                     Ok(addr) => return Some(addr),
 148                     Err(_) => continue,
 149                 }
 150             }
 151         }
 152     }
 153 }
 154
 155 unsafe impl Sync for LookupHost {}
 156 unsafe impl Send for LookupHost {}
 157
 158 impl Drop for LookupHost {
 159     fn drop(&mut self) {
 160         unsafe { c::freeaddrinfo(self.original) }
 161     }
 162 }
 163
 164 pub fn lookup_host(host: &str) -> io::Result<LookupHost> {
 165     init();
 166
 167     let c_host = CString::new(host)?;
 168     let hints = c::addrinfo {
 169         ai_flags: 0,
 170         ai_family: 0,
 171         ai_socktype: c::SOCK_STREAM,
 172         ai_protocol: 0,
 173         ai_addrlen: 0,
 174         ai_addr: ptr::null_mut(),
 175         ai_canonname: ptr::null_mut(),
 176         ai_next: ptr::null_mut()
 177     };
 178     let mut res = ptr::null_mut();
 179     unsafe {
 180         match cvt_gai(c::getaddrinfo(c_host.as_ptr(), ptr::null(), &hints, &mut res)) {
 181             Ok(_) => {
 182                 Ok(LookupHost { original: res, cur: res })
 183             },
 184             #[cfg(unix)]
 185             Err(e) => {
 186                 // The lookup failure could be caused by using a stale /etc/resolv.conf.
 187                 // See https://github.com/rust-lang/rust/issues/41570.
 188                 // We therefore force a reload of the nameserver information.
 189                 c::res_init();
 190                 Err(e)
 191             },
 192             // the cfg is needed here to avoid an "unreachable pattern" warning
 193             #[cfg(not(unix))]
 194             Err(e) => Err(e),
 195         }
 196     }
 197 }
 198
 199 ////////////////////////////////////////////////////////////////////////////////
 200 // TCP streams
 201 ////////////////////////////////////////////////////////////////////////////////
 202
 203 pub struct TcpStream {
 204     inner: Socket,
 205 }
 206
 207 impl TcpStream {
 208     pub fn connect(addr: &SocketAddr) -> io::Result<TcpStream> {
 209         init();
 210
 211         let sock = Socket::new(addr, c::SOCK_STREAM)?;
 212
 213         let (addrp, len) = addr.into_inner();
 214         cvt_r(|| unsafe { c::connect(*sock.as_inner(), addrp, len) })?;
 215         Ok(TcpStream { inner: sock })
 216     }
 217
 218     pub fn socket(&self) -> &Socket { &self.inner }
 219
 220     pub fn into_socket(self) -> Socket { self.inner }
 221
 222     pub fn set_read_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
 223         self.inner.set_timeout(dur, c::SO_RCVTIMEO)
 224     }
 225
 226     pub fn set_write_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
 227         self.inner.set_timeout(dur, c::SO_SNDTIMEO)
 228     }
 229
 230     pub fn read_timeout(&self) -> io::Result<Option<Duration>> {
 231         self.inner.timeout(c::SO_RCVTIMEO)
 232     }
 233
 234     pub fn write_timeout(&self) -> io::Result<Option<Duration>> {
 235         self.inner.timeout(c::SO_SNDTIMEO)
 236     }
 237
 238     pub fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
 239         self.inner.peek(buf)
 240     }
 241
 242     pub fn read(&self, buf: &mut [u8]) -> io::Result<usize> {
 243         self.inner.read(buf)
 244     }
 245
 246     pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
 247         self.inner.read_to_end(buf)
 248     }
 249
 250     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
 251         let len = cmp::min(buf.len(), <wrlen_t>::max_value() as usize) as wrlen_t;
 252         let ret = cvt(unsafe {
 253             c::send(*self.inner.as_inner(),
 254                     buf.as_ptr() as *const c_void,
 255                     len,
 256                     MSG_NOSIGNAL)
 257         })?;
 258         Ok(ret as usize)
 259     }
 260
 261     pub fn peer_addr(&self) -> io::Result<SocketAddr> {
 262         sockname(|buf, len| unsafe {
 263             c::getpeername(*self.inner.as_inner(), buf, len)
 264         })
 265     }
 266
 267     pub fn socket_addr(&self) -> io::Result<SocketAddr> {
 268         sockname(|buf, len| unsafe {
 269             c::getsockname(*self.inner.as_inner(), buf, len)
 270         })
 271     }
 272
 273     pub fn shutdown(&self, how: Shutdown) -> io::Result<()> {
 274         self.inner.shutdown(how)
 275     }
 276
 277     pub fn duplicate(&self) -> io::Result<TcpStream> {
 278         self.inner.duplicate().map(|s| TcpStream { inner: s })
 279     }
 280
 281     pub fn set_nodelay(&self, nodelay: bool) -> io::Result<()> {
 282         self.inner.set_nodelay(nodelay)
 283     }
 284
 285     pub fn nodelay(&self) -> io::Result<bool> {
 286         self.inner.nodelay()
 287     }
 288
 289     pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
 290         setsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL, ttl as c_int)
 291     }
 292
 293     pub fn ttl(&self) -> io::Result<u32> {
 294         let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL)?;
 295         Ok(raw as u32)
 296     }
 297
 298     pub fn take_error(&self) -> io::Result<Option<io::Error>> {
 299         self.inner.take_error()
 300     }
 301
 302     pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
 303         self.inner.set_nonblocking(nonblocking)
 304     }
 305 }
 306
 307 impl FromInner<Socket> for TcpStream {
 308     fn from_inner(socket: Socket) -> TcpStream {
 309         TcpStream { inner: socket }
 310     }
 311 }
 312
 313 impl fmt::Debug for TcpStream {
 314     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 315         let mut res = f.debug_struct("TcpStream");
 316
 317         if let Ok(addr) = self.socket_addr() {
 318             res.field("addr", &addr);
 319         }
 320
 321         if let Ok(peer) = self.peer_addr() {
 322             res.field("peer", &peer);
 323         }
 324
 325         let name = if cfg!(windows) {"socket"} else {"fd"};
 326         res.field(name, &self.inner.as_inner())
 327             .finish()
 328     }
 329 }
 330
 331 ////////////////////////////////////////////////////////////////////////////////
 332 // TCP listeners
 333 ////////////////////////////////////////////////////////////////////////////////
 334
 335 pub struct TcpListener {
 336     inner: Socket,
 337 }
 338
 339 impl TcpListener {
 340     pub fn bind(addr: &SocketAddr) -> io::Result<TcpListener> {
 341         init();
 342
 343         let sock = Socket::new(addr, c::SOCK_STREAM)?;
 344
 345         // On platforms with Berkeley-derived sockets, this allows
 346         // to quickly rebind a socket, without needing to wait for
 347         // the OS to clean up the previous one.
 348         if !cfg!(windows) {
 349             setsockopt(&sock, c::SOL_SOCKET, c::SO_REUSEADDR,
 350                        1 as c_int)?;
 351         }
 352
 353         // Bind our new socket
 354         let (addrp, len) = addr.into_inner();
 355         cvt(unsafe { c::bind(*sock.as_inner(), addrp, len as _) })?;
 356
 357         // Start listening
 358         cvt(unsafe { c::listen(*sock.as_inner(), 128) })?;
 359         Ok(TcpListener { inner: sock })
 360     }
 361
 362     pub fn socket(&self) -> &Socket { &self.inner }
 363
 364     pub fn into_socket(self) -> Socket { self.inner }
 365
 366     pub fn socket_addr(&self) -> io::Result<SocketAddr> {
 367         sockname(|buf, len| unsafe {
 368             c::getsockname(*self.inner.as_inner(), buf, len)
 369         })
 370     }
 371
 372     pub fn accept(&self) -> io::Result<(TcpStream, SocketAddr)> {
 373         let mut storage: c::sockaddr_storage = unsafe { mem::zeroed() };
 374         let mut len = mem::size_of_val(&storage) as c::socklen_t;
 375         let sock = self.inner.accept(&mut storage as *mut _ as *mut _,
 376                                      &mut len)?;
 377         let addr = sockaddr_to_addr(&storage, len as usize)?;
 378         Ok((TcpStream { inner: sock, }, addr))
 379     }
 380
 381     pub fn duplicate(&self) -> io::Result<TcpListener> {
 382         self.inner.duplicate().map(|s| TcpListener { inner: s })
 383     }
 384
 385     pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
 386         setsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL, ttl as c_int)
 387     }
 388
 389     pub fn ttl(&self) -> io::Result<u32> {
 390         let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL)?;
 391         Ok(raw as u32)
 392     }
 393
 394     pub fn set_only_v6(&self, only_v6: bool) -> io::Result<()> {
 395         setsockopt(&self.inner, c::IPPROTO_IPV6, c::IPV6_V6ONLY, only_v6 as c_int)
 396     }
 397
 398     pub fn only_v6(&self) -> io::Result<bool> {
 399         let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IPV6, c::IPV6_V6ONLY)?;
 400         Ok(raw != 0)
 401     }
 402
 403     pub fn take_error(&self) -> io::Result<Option<io::Error>> {
 404         self.inner.take_error()
 405     }
 406
 407     pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
 408         self.inner.set_nonblocking(nonblocking)
 409     }
 410 }
 411
 412 impl FromInner<Socket> for TcpListener {
 413     fn from_inner(socket: Socket) -> TcpListener {
 414         TcpListener { inner: socket }
 415     }
 416 }
 417
 418 impl fmt::Debug for TcpListener {
 419     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 420         let mut res = f.debug_struct("TcpListener");
 421
 422         if let Ok(addr) = self.socket_addr() {
 423             res.field("addr", &addr);
 424         }
 425
 426         let name = if cfg!(windows) {"socket"} else {"fd"};
 427         res.field(name, &self.inner.as_inner())
 428             .finish()
 429     }
 430 }
 431
 432 ////////////////////////////////////////////////////////////////////////////////
 433 // UDP
 434 ////////////////////////////////////////////////////////////////////////////////
 435
 436 pub struct UdpSocket {
 437     inner: Socket,
 438 }
 439
 440 impl UdpSocket {
 441     pub fn bind(addr: &SocketAddr) -> io::Result<UdpSocket> {
 442         init();
 443
 444         let sock = Socket::new(addr, c::SOCK_DGRAM)?;
 445         let (addrp, len) = addr.into_inner();
 446         cvt(unsafe { c::bind(*sock.as_inner(), addrp, len as _) })?;
 447         Ok(UdpSocket { inner: sock })
 448     }
 449
 450     pub fn socket(&self) -> &Socket { &self.inner }
 451
 452     pub fn into_socket(self) -> Socket { self.inner }
 453
 454     pub fn socket_addr(&self) -> io::Result<SocketAddr> {
 455         sockname(|buf, len| unsafe {
 456             c::getsockname(*self.inner.as_inner(), buf, len)
 457         })
 458     }
 459
 460     pub fn recv_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
 461         self.inner.recv_from(buf)
 462     }
 463
 464     pub fn peek_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
 465         self.inner.peek_from(buf)
 466     }
 467
 468     pub fn send_to(&self, buf: &[u8], dst: &SocketAddr) -> io::Result<usize> {
 469         let len = cmp::min(buf.len(), <wrlen_t>::max_value() as usize) as wrlen_t;
 470         let (dstp, dstlen) = dst.into_inner();
 471         let ret = cvt(unsafe {
 472             c::sendto(*self.inner.as_inner(),
 473                       buf.as_ptr() as *const c_void, len,
 474                       MSG_NOSIGNAL, dstp, dstlen)
 475         })?;
 476         Ok(ret as usize)
 477     }
 478
 479     pub fn duplicate(&self) -> io::Result<UdpSocket> {
 480         self.inner.duplicate().map(|s| UdpSocket { inner: s })
 481     }
 482
 483     pub fn set_read_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
 484         self.inner.set_timeout(dur, c::SO_RCVTIMEO)
 485     }
 486
 487     pub fn set_write_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
 488         self.inner.set_timeout(dur, c::SO_SNDTIMEO)
 489     }
 490
 491     pub fn read_timeout(&self) -> io::Result<Option<Duration>> {
 492         self.inner.timeout(c::SO_RCVTIMEO)
 493     }
 494
 495     pub fn write_timeout(&self) -> io::Result<Option<Duration>> {
 496         self.inner.timeout(c::SO_SNDTIMEO)
 497     }
 498
 499     pub fn set_broadcast(&self, broadcast: bool) -> io::Result<()> {
 500         setsockopt(&self.inner, c::SOL_SOCKET, c::SO_BROADCAST, broadcast as c_int)
 501     }
 502
 503     pub fn broadcast(&self) -> io::Result<bool> {
 504         let raw: c_int = getsockopt(&self.inner, c::SOL_SOCKET, c::SO_BROADCAST)?;
 505         Ok(raw != 0)
 506     }
 507
 508     pub fn set_multicast_loop_v4(&self, multicast_loop_v4: bool) -> io::Result<()> {
 509         setsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_LOOP, multicast_loop_v4 as c_int)
 510     }
 511
 512     pub fn multicast_loop_v4(&self) -> io::Result<bool> {
 513         let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_LOOP)?;
 514         Ok(raw != 0)
 515     }
 516
 517     pub fn set_multicast_ttl_v4(&self, multicast_ttl_v4: u32) -> io::Result<()> {
 518         setsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_TTL, multicast_ttl_v4 as c_int)
 519     }
 520
 521     pub fn multicast_ttl_v4(&self) -> io::Result<u32> {
 522         let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_TTL)?;
 523         Ok(raw as u32)
 524     }
 525
 526     pub fn set_multicast_loop_v6(&self, multicast_loop_v6: bool) -> io::Result<()> {
 527         setsockopt(&self.inner, c::IPPROTO_IPV6, c::IPV6_MULTICAST_LOOP, multicast_loop_v6 as c_int)
 528     }
 529
 530     pub fn multicast_loop_v6(&self) -> io::Result<bool> {
 531         let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IPV6, c::IPV6_MULTICAST_LOOP)?;
 532         Ok(raw != 0)
 533     }
 534
 535     pub fn join_multicast_v4(&self, multiaddr: &Ipv4Addr, interface: &Ipv4Addr)
 536                          -> io::Result<()> {
 537         let mreq = c::ip_mreq {
 538             imr_multiaddr: *multiaddr.as_inner(),
 539             imr_interface: *interface.as_inner(),
 540         };
 541         setsockopt(&self.inner, c::IPPROTO_IP, c::IP_ADD_MEMBERSHIP, mreq)
 542     }
 543
 544     pub fn join_multicast_v6(&self, multiaddr: &Ipv6Addr, interface: u32)
 545                          -> io::Result<()> {
 546         let mreq = c::ipv6_mreq {
 547             ipv6mr_multiaddr: *multiaddr.as_inner(),
 548             ipv6mr_interface: to_ipv6mr_interface(interface),
 549         };
 550         setsockopt(&self.inner, c::IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, mreq)
 551     }
 552
 553     pub fn leave_multicast_v4(&self, multiaddr: &Ipv4Addr, interface: &Ipv4Addr)
 554                           -> io::Result<()> {
 555         let mreq = c::ip_mreq {
 556             imr_multiaddr: *multiaddr.as_inner(),
 557             imr_interface: *interface.as_inner(),
 558         };
 559         setsockopt(&self.inner, c::IPPROTO_IP, c::IP_DROP_MEMBERSHIP, mreq)
 560     }
 561
 562     pub fn leave_multicast_v6(&self, multiaddr: &Ipv6Addr, interface: u32)
 563                           -> io::Result<()> {
 564         let mreq = c::ipv6_mreq {
 565             ipv6mr_multiaddr: *multiaddr.as_inner(),
 566             ipv6mr_interface: to_ipv6mr_interface(interface),
 567         };
 568         setsockopt(&self.inner, c::IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, mreq)
 569     }
 570
 571     pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
 572         setsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL, ttl as c_int)
 573     }
 574
 575     pub fn ttl(&self) -> io::Result<u32> {
 576         let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL)?;
 577         Ok(raw as u32)
 578     }
 579
 580     pub fn take_error(&self) -> io::Result<Option<io::Error>> {
 581         self.inner.take_error()
 582     }
 583
 584     pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
 585         self.inner.set_nonblocking(nonblocking)
 586     }
 587
 588     pub fn recv(&self, buf: &mut [u8]) -> io::Result<usize> {
 589         self.inner.read(buf)
 590     }
 591
 592     pub fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
 593         self.inner.peek(buf)
 594     }
 595
 596     pub fn send(&self, buf: &[u8]) -> io::Result<usize> {
 597         let len = cmp::min(buf.len(), <wrlen_t>::max_value() as usize) as wrlen_t;
 598         let ret = cvt(unsafe {
 599             c::send(*self.inner.as_inner(),
 600                     buf.as_ptr() as *const c_void,
 601                     len,
 602                     MSG_NOSIGNAL)
 603         })?;
 604         Ok(ret as usize)
 605     }
 606
 607     pub fn connect(&self, addr: &SocketAddr) -> io::Result<()> {
 608         let (addrp, len) = addr.into_inner();
 609         cvt_r(|| unsafe { c::connect(*self.inner.as_inner(), addrp, len) }).map(|_| ())
 610     }
 611 }
 612
 613 impl FromInner<Socket> for UdpSocket {
 614     fn from_inner(socket: Socket) -> UdpSocket {
 615         UdpSocket { inner: socket }
 616     }
 617 }
 618
 619 impl fmt::Debug for UdpSocket {
 620     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 621         let mut res = f.debug_struct("UdpSocket");
 622
 623         if let Ok(addr) = self.socket_addr() {
 624             res.field("addr", &addr);
 625         }
 626
 627         let name = if cfg!(windows) {"socket"} else {"fd"};
 628         res.field(name, &self.inner.as_inner())
 629             .finish()
 630     }
 631 }
 632
 633 #[cfg(test)]
 634 mod tests {
 635     use super::*;
 636     use collections::HashMap;
 637
 638     #[test]
 639     fn no_lookup_host_duplicates() {
 640         let mut addrs = HashMap::new();
 641         let lh = match lookup_host("localhost") {
 642             Ok(lh) => lh,
 643             Err(e) => panic!("couldn't resolve `localhost': {}", e)
 644         };
 645         let _na = lh.map(|sa| *addrs.entry(sa).or_insert(0) += 1).count();
 646         assert!(addrs.values().filter(|&&v| v > 1).count() == 0);
 647     }
 648 }