1 files changed, 630 insertions, 0 deletions
diff --git a/ctr-std/src/sys_common/net.rs b/ctr-std/src/sys_common/net.rs
new file mode 100644
index 0000000..6223f82
--- /dev/null
+++ b/ctr-std/src/sys_common/net.rs
@@ -0,0 +1,630 @@
+// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(dead_code)]
+
+use cmp;
+use ffi::CString;
+use fmt;
+use io::{self, Error, ErrorKind};
+use libc::{c_int, c_void};
+use mem;
+use net::{SocketAddr, Shutdown, Ipv4Addr, Ipv6Addr};
+use ptr;
+use sys::net::{cvt, cvt_r, cvt_gai, Socket, init, wrlen_t};
+use sys::net::netc as c;
+use sys_common::{AsInner, FromInner, IntoInner};
+use time::Duration;
+
+// IPV6 stuff does not seem to be supported on 3DS. TODO: Determine if that's true
+const IPV6_ADD_MEMBERSHIP: c_int = 0x0;
+const IPV6_DROP_MEMBERSHIP: c_int = 0x0;
+const IPV6_MULTICAST_LOOP: c_int = 0x0;
+const IPV6_V6ONLY: c_int = 0x0;
+
+// Neither are signals
+const MSG_NOSIGNAL: c_int = 0x0;
+
+// These constants are also currently missing from libctru. TODO: Find them?
+const SO_SNDTIMEO: c_int = 0x0;
+const SO_RCVTIMEO: c_int = 0x0;
+const SO_BROADCAST: c_int = 0x0;
+
+////////////////////////////////////////////////////////////////////////////////
+// sockaddr and misc bindings
+////////////////////////////////////////////////////////////////////////////////
+
+pub fn setsockopt<T>(sock: &Socket, opt: c_int, val: c_int,
+                     payload: T) -> io::Result<()> {
+    unsafe {
+        let payload = &payload as *const T as *const c_void;
+        cvt(c::setsockopt(*sock.as_inner(), opt, val, payload,
+                          mem::size_of::<T>() as c::socklen_t))?;
+        Ok(())
+    }
+}
+
+pub fn getsockopt<T: Copy>(sock: &Socket, opt: c_int,
+                       val: c_int) -> io::Result<T> {
+    unsafe {
+        let mut slot: T = mem::zeroed();
+        let mut len = mem::size_of::<T>() as c::socklen_t;
+        cvt(c::getsockopt(*sock.as_inner(), opt, val,
+                          &mut slot as *mut _ as *mut _,
+                          &mut len))?;
+        assert_eq!(len as usize, mem::size_of::<T>());
+        Ok(slot)
+    }
+}
+
+fn sockname<F>(f: F) -> io::Result<SocketAddr>
+    where F: FnOnce(*mut c::sockaddr, *mut c::socklen_t) -> c_int
+{
+    unsafe {
+        let mut storage: c::sockaddr_storage = mem::zeroed();
+        let mut len = mem::size_of_val(&storage) as c::socklen_t;
+        cvt(f(&mut storage as *mut _ as *mut _, &mut len))?;
+        sockaddr_to_addr(&storage, len as usize)
+    }
+}
+
+pub fn sockaddr_to_addr(storage: &c::sockaddr_storage,
+                    len: usize) -> io::Result<SocketAddr> {
+    match storage.ss_family as c_int {
+        c::AF_INET => {
+            assert!(len as usize >= mem::size_of::<c::sockaddr_in>());
+            Ok(SocketAddr::V4(FromInner::from_inner(unsafe {
+                *(storage as *const _ as *const c::sockaddr_in)
+            })))
+        }
+        c::AF_INET6 => {
+            assert!(len as usize >= mem::size_of::<c::sockaddr_in6>());
+            Ok(SocketAddr::V6(FromInner::from_inner(unsafe {
+                *(storage as *const _ as *const c::sockaddr_in6)
+            })))
+        }
+        _ => {
+            Err(Error::new(ErrorKind::InvalidInput, "invalid argument"))
+        }
+    }
+}
+
+#[cfg(target_os = "android")]
+fn to_ipv6mr_interface(value: u32) -> c_int {
+    value as c_int
+}
+
+#[cfg(not(target_os = "android"))]
+fn to_ipv6mr_interface(value: u32) -> ::libc::c_uint {
+    value as ::libc::c_uint
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// get_host_addresses
+////////////////////////////////////////////////////////////////////////////////
+
+pub struct LookupHost {
+    original: *mut c::addrinfo,
+    cur: *mut c::addrinfo,
+}
+
+impl Iterator for LookupHost {
+    type Item = SocketAddr;
+    fn next(&mut self) -> Option<SocketAddr> {
+        loop {
+            unsafe {
+                let cur = self.cur.as_ref()?;
+                self.cur = cur.ai_next;
+                match sockaddr_to_addr(mem::transmute(cur.ai_addr),
+                                       cur.ai_addrlen as usize)
+                {
+                    Ok(addr) => return Some(addr),
+                    Err(_) => continue,
+                }
+            }
+        }
+    }
+}
+
+unsafe impl Sync for LookupHost {}
+unsafe impl Send for LookupHost {}
+
+impl Drop for LookupHost {
+    fn drop(&mut self) {
+        unsafe { c::freeaddrinfo(self.original) }
+    }
+}
+
+pub fn lookup_host(host: &str) -> io::Result<LookupHost> {
+    init();
+
+    let c_host = CString::new(host)?;
+    let mut hints: c::addrinfo = unsafe { mem::zeroed() };
+    hints.ai_socktype = c::SOCK_STREAM;
+    let mut res = ptr::null_mut();
+    unsafe {
+        match cvt_gai(c::getaddrinfo(c_host.as_ptr(), ptr::null(), &hints, &mut res)) {
+            Ok(_) => {
+                Ok(LookupHost { original: res, cur: res })
+            },
+            #[cfg(unix)]
+            Err(e) => {
+                // If we're running glibc prior to version 2.26, the lookup
+                // failure could be caused by caching a stale /etc/resolv.conf.
+                // We need to call libc::res_init() to clear the cache. But we
+                // shouldn't call it in on any other platform, because other
+                // res_init implementations aren't thread-safe. See
+                // https://github.com/rust-lang/rust/issues/41570 and
+                // https://github.com/rust-lang/rust/issues/43592.
+                use sys::net::res_init_if_glibc_before_2_26;
+                let _ = res_init_if_glibc_before_2_26();
+                Err(e)
+            },
+            // the cfg is needed here to avoid an "unreachable pattern" warning
+            #[cfg(not(unix))]
+            Err(e) => Err(e),
+        }
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// TCP streams
+////////////////////////////////////////////////////////////////////////////////
+
+pub struct TcpStream {
+    inner: Socket,
+}
+
+impl TcpStream {
+    pub fn connect(addr: &SocketAddr) -> io::Result<TcpStream> {
+        init();
+
+        let sock = Socket::new(addr, c::SOCK_STREAM)?;
+
+        let (addrp, len) = addr.into_inner();
+        cvt_r(|| unsafe { c::connect(*sock.as_inner(), addrp, len) })?;
+        Ok(TcpStream { inner: sock })
+    }
+
+    pub fn connect_timeout(addr: &SocketAddr, timeout: Duration) -> io::Result<TcpStream> {
+        init();
+
+        let sock = Socket::new(addr, c::SOCK_STREAM)?;
+        sock.connect_timeout(addr, timeout)?;
+        Ok(TcpStream { inner: sock })
+    }
+
+    pub fn socket(&self) -> &Socket { &self.inner }
+
+    pub fn into_socket(self) -> Socket { self.inner }
+
+    pub fn set_read_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
+        self.inner.set_timeout(dur, SO_RCVTIMEO)
+    }
+
+    pub fn set_write_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
+        self.inner.set_timeout(dur, SO_SNDTIMEO)
+    }
+
+    pub fn read_timeout(&self) -> io::Result<Option<Duration>> {
+        self.inner.timeout(SO_RCVTIMEO)
+    }
+
+    pub fn write_timeout(&self) -> io::Result<Option<Duration>> {
+        self.inner.timeout(SO_SNDTIMEO)
+    }
+
+    pub fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.inner.peek(buf)
+    }
+
+    pub fn read(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.inner.read(buf)
+    }
+
+    pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
+        let len = cmp::min(buf.len(), <wrlen_t>::max_value() as usize) as wrlen_t;
+        let ret = cvt(unsafe {
+            c::send(*self.inner.as_inner(),
+                    buf.as_ptr() as *const c_void,
+                    len,
+                    MSG_NOSIGNAL)
+        })?;
+        Ok(ret as usize)
+    }
+
+    pub fn peer_addr(&self) -> io::Result<SocketAddr> {
+        sockname(|buf, len| unsafe {
+            c::getpeername(*self.inner.as_inner(), buf, len)
+        })
+    }
+
+    pub fn socket_addr(&self) -> io::Result<SocketAddr> {
+        sockname(|buf, len| unsafe {
+            c::getsockname(*self.inner.as_inner(), buf, len)
+        })
+    }
+
+    pub fn shutdown(&self, how: Shutdown) -> io::Result<()> {
+        self.inner.shutdown(how)
+    }
+
+    pub fn duplicate(&self) -> io::Result<TcpStream> {
+        self.inner.duplicate().map(|s| TcpStream { inner: s })
+    }
+
+    pub fn set_nodelay(&self, nodelay: bool) -> io::Result<()> {
+        self.inner.set_nodelay(nodelay)
+    }
+
+    pub fn nodelay(&self) -> io::Result<bool> {
+        self.inner.nodelay()
+    }
+
+    pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
+        setsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL, ttl as c_int)
+    }
+
+    pub fn ttl(&self) -> io::Result<u32> {
+        let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL)?;
+        Ok(raw as u32)
+    }
+
+    pub fn take_error(&self) -> io::Result<Option<io::Error>> {
+        self.inner.take_error()
+    }
+
+    pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
+        self.inner.set_nonblocking(nonblocking)
+    }
+}
+
+impl FromInner<Socket> for TcpStream {
+    fn from_inner(socket: Socket) -> TcpStream {
+        TcpStream { inner: socket }
+    }
+}
+
+impl fmt::Debug for TcpStream {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let mut res = f.debug_struct("TcpStream");
+
+        if let Ok(addr) = self.socket_addr() {
+            res.field("addr", &addr);
+        }
+
+        if let Ok(peer) = self.peer_addr() {
+            res.field("peer", &peer);
+        }
+
+        let name = if cfg!(windows) {"socket"} else {"fd"};
+        res.field(name, &self.inner.as_inner())
+            .finish()
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// TCP listeners
+////////////////////////////////////////////////////////////////////////////////
+
+pub struct TcpListener {
+    inner: Socket,
+}
+
+impl TcpListener {
+    pub fn bind(addr: &SocketAddr) -> io::Result<TcpListener> {
+        init();
+
+        let sock = Socket::new(addr, c::SOCK_STREAM)?;
+
+        // On platforms with Berkeley-derived sockets, this allows
+        // to quickly rebind a socket, without needing to wait for
+        // the OS to clean up the previous one.
+        if !cfg!(windows) {
+            setsockopt(&sock, c::SOL_SOCKET, c::SO_REUSEADDR,
+                       1 as c_int)?;
+        }
+
+        // Bind our new socket
+        let (addrp, len) = addr.into_inner();
+        cvt(unsafe { c::bind(*sock.as_inner(), addrp, len as _) })?;
+
+        // Start listening
+        cvt(unsafe { c::listen(*sock.as_inner(), 128) })?;
+        Ok(TcpListener { inner: sock })
+    }
+
+    pub fn socket(&self) -> &Socket { &self.inner }
+
+    pub fn into_socket(self) -> Socket { self.inner }
+
+    pub fn socket_addr(&self) -> io::Result<SocketAddr> {
+        sockname(|buf, len| unsafe {
+            c::getsockname(*self.inner.as_inner(), buf, len)
+        })
+    }
+
+    pub fn accept(&self) -> io::Result<(TcpStream, SocketAddr)> {
+        let mut storage: c::sockaddr_storage = unsafe { mem::zeroed() };
+        let mut len = mem::size_of_val(&storage) as c::socklen_t;
+        let sock = self.inner.accept(&mut storage as *mut _ as *mut _,
+                                     &mut len)?;
+        let addr = sockaddr_to_addr(&storage, len as usize)?;
+        Ok((TcpStream { inner: sock, }, addr))
+    }
+
+    pub fn duplicate(&self) -> io::Result<TcpListener> {
+        self.inner.duplicate().map(|s| TcpListener { inner: s })
+    }
+
+    pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
+        setsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL, ttl as c_int)
+    }
+
+    pub fn ttl(&self) -> io::Result<u32> {
+        let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL)?;
+        Ok(raw as u32)
+    }
+
+    pub fn set_only_v6(&self, only_v6: bool) -> io::Result<()> {
+        setsockopt(&self.inner, c::IPPROTO_IPV6, IPV6_V6ONLY, only_v6 as c_int)
+    }
+
+    pub fn only_v6(&self) -> io::Result<bool> {
+        let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IPV6, IPV6_V6ONLY)?;
+        Ok(raw != 0)
+    }
+
+    pub fn take_error(&self) -> io::Result<Option<io::Error>> {
+        self.inner.take_error()
+    }
+
+    pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
+        self.inner.set_nonblocking(nonblocking)
+    }
+}
+
+impl FromInner<Socket> for TcpListener {
+    fn from_inner(socket: Socket) -> TcpListener {
+        TcpListener { inner: socket }
+    }
+}
+
+impl fmt::Debug for TcpListener {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let mut res = f.debug_struct("TcpListener");
+
+        if let Ok(addr) = self.socket_addr() {
+            res.field("addr", &addr);
+        }
+
+        let name = if cfg!(windows) {"socket"} else {"fd"};
+        res.field(name, &self.inner.as_inner())
+            .finish()
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// UDP
+////////////////////////////////////////////////////////////////////////////////
+
+pub struct UdpSocket {
+    inner: Socket,
+}
+
+impl UdpSocket {
+    pub fn bind(addr: &SocketAddr) -> io::Result<UdpSocket> {
+        init();
+
+        let sock = Socket::new(addr, c::SOCK_DGRAM)?;
+        let (addrp, len) = addr.into_inner();
+        cvt(unsafe { c::bind(*sock.as_inner(), addrp, len as _) })?;
+        Ok(UdpSocket { inner: sock })
+    }
+
+    pub fn socket(&self) -> &Socket { &self.inner }
+
+    pub fn into_socket(self) -> Socket { self.inner }
+
+    pub fn socket_addr(&self) -> io::Result<SocketAddr> {
+        sockname(|buf, len| unsafe {
+            c::getsockname(*self.inner.as_inner(), buf, len)
+        })
+    }
+
+    pub fn recv_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
+        self.inner.recv_from(buf)
+    }
+
+    pub fn peek_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
+        self.inner.peek_from(buf)
+    }
+
+    pub fn send_to(&self, buf: &[u8], dst: &SocketAddr) -> io::Result<usize> {
+        let len = cmp::min(buf.len(), <wrlen_t>::max_value() as usize) as wrlen_t;
+        let (dstp, dstlen) = dst.into_inner();
+        let ret = cvt(unsafe {
+            c::sendto(*self.inner.as_inner(),
+                      buf.as_ptr() as *const c_void, len,
+                      MSG_NOSIGNAL, dstp, dstlen)
+        })?;
+        Ok(ret as usize)
+    }
+
+    pub fn duplicate(&self) -> io::Result<UdpSocket> {
+        self.inner.duplicate().map(|s| UdpSocket { inner: s })
+    }
+
+    pub fn set_read_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
+        self.inner.set_timeout(dur, SO_RCVTIMEO)
+    }
+
+    pub fn set_write_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
+        self.inner.set_timeout(dur, SO_SNDTIMEO)
+    }
+
+    pub fn read_timeout(&self) -> io::Result<Option<Duration>> {
+        self.inner.timeout(SO_RCVTIMEO)
+    }
+
+    pub fn write_timeout(&self) -> io::Result<Option<Duration>> {
+        self.inner.timeout(SO_SNDTIMEO)
+    }
+
+    pub fn set_broadcast(&self, broadcast: bool) -> io::Result<()> {
+        setsockopt(&self.inner, c::SOL_SOCKET, SO_BROADCAST, broadcast as c_int)
+    }
+
+    pub fn broadcast(&self) -> io::Result<bool> {
+        let raw: c_int = getsockopt(&self.inner, c::SOL_SOCKET, SO_BROADCAST)?;
+        Ok(raw != 0)
+    }
+
+    pub fn set_multicast_loop_v4(&self, multicast_loop_v4: bool) -> io::Result<()> {
+        setsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_LOOP, multicast_loop_v4 as c_int)
+    }
+
+    pub fn multicast_loop_v4(&self) -> io::Result<bool> {
+        let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_LOOP)?;
+        Ok(raw != 0)
+    }
+
+    pub fn set_multicast_ttl_v4(&self, multicast_ttl_v4: u32) -> io::Result<()> {
+        setsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_TTL, multicast_ttl_v4 as c_int)
+    }
+
+    pub fn multicast_ttl_v4(&self) -> io::Result<u32> {
+        let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_MULTICAST_TTL)?;
+        Ok(raw as u32)
+    }
+
+    pub fn set_multicast_loop_v6(&self, multicast_loop_v6: bool) -> io::Result<()> {
+        setsockopt(&self.inner, c::IPPROTO_IPV6, IPV6_MULTICAST_LOOP, multicast_loop_v6 as c_int)
+    }
+
+    pub fn multicast_loop_v6(&self) -> io::Result<bool> {
+        let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IPV6, IPV6_MULTICAST_LOOP)?;
+        Ok(raw != 0)
+    }
+
+    pub fn join_multicast_v4(&self, multiaddr: &Ipv4Addr, interface: &Ipv4Addr)
+                         -> io::Result<()> {
+        let mreq = c::ip_mreq {
+            imr_multiaddr: *multiaddr.as_inner(),
+            imr_interface: *interface.as_inner(),
+        };
+        setsockopt(&self.inner, c::IPPROTO_IP, c::IP_ADD_MEMBERSHIP, mreq)
+    }
+
+    pub fn join_multicast_v6(&self, multiaddr: &Ipv6Addr, interface: u32)
+                         -> io::Result<()> {
+        let mreq = c::ipv6_mreq {
+            ipv6mr_multiaddr: *multiaddr.as_inner(),
+            ipv6mr_interface: to_ipv6mr_interface(interface),
+        };
+        setsockopt(&self.inner, c::IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, mreq)
+    }
+
+    pub fn leave_multicast_v4(&self, multiaddr: &Ipv4Addr, interface: &Ipv4Addr)
+                          -> io::Result<()> {
+        let mreq = c::ip_mreq {
+            imr_multiaddr: *multiaddr.as_inner(),
+            imr_interface: *interface.as_inner(),
+        };
+        setsockopt(&self.inner, c::IPPROTO_IP, c::IP_DROP_MEMBERSHIP, mreq)
+    }
+
+    pub fn leave_multicast_v6(&self, multiaddr: &Ipv6Addr, interface: u32)
+                          -> io::Result<()> {
+        let mreq = c::ipv6_mreq {
+            ipv6mr_multiaddr: *multiaddr.as_inner(),
+            ipv6mr_interface: to_ipv6mr_interface(interface),
+        };
+        setsockopt(&self.inner, c::IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, mreq)
+    }
+
+    pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
+        setsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL, ttl as c_int)
+    }
+
+    pub fn ttl(&self) -> io::Result<u32> {
+        let raw: c_int = getsockopt(&self.inner, c::IPPROTO_IP, c::IP_TTL)?;
+        Ok(raw as u32)
+    }
+
+    pub fn take_error(&self) -> io::Result<Option<io::Error>> {
+        self.inner.take_error()
+    }
+
+    pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
+        self.inner.set_nonblocking(nonblocking)
+    }
+
+    pub fn recv(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.inner.read(buf)
+    }
+
+    pub fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.inner.peek(buf)
+    }
+
+    pub fn send(&self, buf: &[u8]) -> io::Result<usize> {
+        let len = cmp::min(buf.len(), <wrlen_t>::max_value() as usize) as wrlen_t;
+        let ret = cvt(unsafe {
+            c::send(*self.inner.as_inner(),
+                    buf.as_ptr() as *const c_void,
+                    len,
+                    MSG_NOSIGNAL)
+        })?;
+        Ok(ret as usize)
+    }
+
+    pub fn connect(&self, addr: &SocketAddr) -> io::Result<()> {
+        let (addrp, len) = addr.into_inner();
+        cvt_r(|| unsafe { c::connect(*self.inner.as_inner(), addrp, len) }).map(|_| ())
+    }
+}
+
+impl FromInner<Socket> for UdpSocket {
+    fn from_inner(socket: Socket) -> UdpSocket {
+        UdpSocket { inner: socket }
+    }
+}
+
+impl fmt::Debug for UdpSocket {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let mut res = f.debug_struct("UdpSocket");
+
+        if let Ok(addr) = self.socket_addr() {
+            res.field("addr", &addr);
+        }
+
+        let name = if cfg!(windows) {"socket"} else {"fd"};
+        res.field(name, &self.inner.as_inner())
+            .finish()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use collections::HashMap;
+
+    #[test]
+    fn no_lookup_host_duplicates() {
+        let mut addrs = HashMap::new();
+        let lh = match lookup_host("localhost") {
+            Ok(lh) => lh,
+            Err(e) => panic!("couldn't resolve `localhost': {}", e)
+        };
+        let _na = lh.map(|sa| *addrs.entry(sa).or_insert(0) += 1).count();
+        assert!(addrs.values().filter(|&&v| v > 1).count() == 0);
+    }
+}