Refactor net::each_addr/lookup_host to forward error from resolve

Author: Jethro Beekman

src/libstd/net/addr.rs

@@ -16,10 +16,11 @@ use net::{ntoh, hton, IpAddr, Ipv4Addr, Ipv6Addr};
 use option;
 use sys::net::netc as c;
 use sys_common::{FromInner, AsInner, IntoInner};
-use sys_common::net::lookup_host;
+use sys_common::net::LookupHost;
 use vec;
 use iter;
 use slice;
+use convert::TryInto;
 
 /// An internet socket address, either IPv4 or IPv6.
 ///
@@ -863,9 +864,9 @@ impl ToSocketAddrs for (Ipv6Addr, u16) {
     }
 }
 
-fn resolve_socket_addr(s: &str, p: u16) -> io::Result<vec::IntoIter<SocketAddr>> {
-    let ips = lookup_host(s)?;
-    let v: Vec<_> = ips.map(|mut a| { a.set_port(p); a }).collect();
+fn resolve_socket_addr(lh: LookupHost) -> io::Result<vec::IntoIter<SocketAddr>> {
+    let p = lh.port();
+    let v: Vec<_> = lh.map(|mut a| { a.set_port(p); a }).collect();
     Ok(v.into_iter())
 }
 
@@ -885,7 +886,7 @@ impl<'a> ToSocketAddrs for (&'a str, u16) {
             return Ok(vec![SocketAddr::V6(addr)].into_iter())
         }
 
-        resolve_socket_addr(host, port)
+        resolve_socket_addr((host, port).try_into()?)
     }
 }
 
@@ -899,22 +900,7 @@ impl ToSocketAddrs for str {
             return Ok(vec![addr].into_iter());
         }
 
-        macro_rules! try_opt {
-            ($e:expr, $msg:expr) => (
-                match $e {
-                    Some(r) => r,
-                    None => return Err(io::Error::new(io::ErrorKind::InvalidInput,
-                                                      $msg)),
-                }
-            )
-        }
-
-        // split the string by ':' and convert the second part to u16
-        let mut parts_iter = self.rsplitn(2, ':');
-        let port_str = try_opt!(parts_iter.next(), "invalid socket address");
-        let host = try_opt!(parts_iter.next(), "invalid socket address");
-        let port: u16 = try_opt!(port_str.parse().ok(), "invalid port value");
-        resolve_socket_addr(host, port)
+        resolve_socket_addr(self.try_into()?)
     }
 }
 

src/libstd/net/mod.rs

@@ -112,11 +112,15 @@ fn hton<I: NetInt>(i: I) -> I { i.to_be() }
 fn ntoh<I: NetInt>(i: I) -> I { I::from_be(i) }
 
 fn each_addr<A: ToSocketAddrs, F, T>(addr: A, mut f: F) -> io::Result<T>
-    where F: FnMut(&SocketAddr) -> io::Result<T>
+    where F: FnMut(io::Result<&SocketAddr>) -> io::Result<T>
 {
+    let addrs = match addr.to_socket_addrs() {
+        Ok(addrs) => addrs,
+        Err(e) => return f(Err(e))
+    };
     let mut last_err = None;
-    for addr in addr.to_socket_addrs()? {
-        match f(&addr) {
+    for addr in addrs {
+        match f(Ok(&addr)) {
             Ok(l) => return Ok(l),
             Err(e) => last_err = Some(e),
         }

src/libstd/sys/cloudabi/shims/net.rs

@@ -13,13 +13,14 @@ use io;
 use net::{Ipv4Addr, Ipv6Addr, Shutdown, SocketAddr};
 use time::Duration;
 use sys::{unsupported, Void};
+use convert::TryFrom;
 
 pub extern crate libc as netc;
 
 pub struct TcpStream(Void);
 
 impl TcpStream {
-    pub fn connect(_: &SocketAddr) -> io::Result<TcpStream> {
+    pub fn connect(_: io::Result<&SocketAddr>) -> io::Result<TcpStream> {
         unsupported()
     }
 
@@ -105,7 +106,7 @@ impl fmt::Debug for TcpStream {
 pub struct TcpListener(Void);
 
 impl TcpListener {
-    pub fn bind(_: &SocketAddr) -> io::Result<TcpListener> {
+    pub fn bind(_: io::Result<&SocketAddr>) -> io::Result<TcpListener> {
         unsupported()
     }
 
@@ -155,7 +156,7 @@ impl fmt::Debug for TcpListener {
 pub struct UdpSocket(Void);
 
 impl UdpSocket {
-    pub fn bind(_: &SocketAddr) -> io::Result<UdpSocket> {
+    pub fn bind(_: io::Result<&SocketAddr>) -> io::Result<UdpSocket> {
         unsupported()
     }
 
@@ -271,7 +272,7 @@ impl UdpSocket {
         match self.0 {}
     }
 
-    pub fn connect(&self, _: &SocketAddr) -> io::Result<()> {
+    pub fn connect(&self, _: io::Result<&SocketAddr>) -> io::Result<()> {
         match self.0 {}
     }
 }
@@ -284,13 +285,31 @@ impl fmt::Debug for UdpSocket {
 
 pub struct LookupHost(Void);
 
+impl LookupHost {
+    pub fn port(&self) -> u16 {
+        match self.0 {}
+    }
+}
+
 impl Iterator for LookupHost {
     type Item = SocketAddr;
     fn next(&mut self) -> Option<SocketAddr> {
         match self.0 {}
     }
 }
 
-pub fn lookup_host(_: &str) -> io::Result<LookupHost> {
-    unsupported()
+impl<'a> TryFrom<&'a str> for LookupHost {
+    type Error = io::Error;
+
+    fn try_from(_v: &'a str) -> io::Result<LookupHost> {
+        unsupported()
+    }
+}
+
+impl<'a> TryFrom<(&'a str, u16)> for LookupHost {
+    type Error = io::Error;
+
+    fn try_from(_v: (&'a str, u16)) -> io::Result<LookupHost> {
+        unsupported()
+    }
 }

src/libstd/sys/redox/net/mod.rs

@@ -9,14 +9,15 @@
 // except according to those terms.
 
 use fs::File;
-use io::{Error, Result, Read};
+use io::{Error, Read, self};
 use iter::Iterator;
 use net::{Ipv4Addr, SocketAddr, SocketAddrV4};
 use str::FromStr;
 use string::{String, ToString};
 use sys::syscall::EINVAL;
 use time::{self, Duration};
 use vec::{IntoIter, Vec};
+use convert::{TryFrom, TryInto};
 
 use self::dns::{Dns, DnsQuery};
 
@@ -29,7 +30,13 @@ mod dns;
 mod tcp;
 mod udp;
 
-pub struct LookupHost(IntoIter<SocketAddr>);
+pub struct LookupHost(IntoIter<SocketAddr>, u16);
+
+impl LookupHost {
+    pub fn port(&self) -> u16 {
+        self.1
+    }
+}
 
 impl Iterator for LookupHost {
     type Item = SocketAddr;
@@ -38,65 +45,93 @@ impl Iterator for LookupHost {
     }
 }
 
-pub fn lookup_host(host: &str) -> Result<LookupHost> {
-    let mut ip_string = String::new();
-    File::open("/etc/net/ip")?.read_to_string(&mut ip_string)?;
-    let ip: Vec<u8> = ip_string.trim().split('.').map(|part| part.parse::<u8>()
-                               .unwrap_or(0)).collect();
-
-    let mut dns_string = String::new();
-    File::open("/etc/net/dns")?.read_to_string(&mut dns_string)?;
-    let dns: Vec<u8> = dns_string.trim().split('.').map(|part| part.parse::<u8>()
-                                 .unwrap_or(0)).collect();
-
-    if ip.len() == 4 && dns.len() == 4 {
-        let time = time::SystemTime::now().duration_since(time::UNIX_EPOCH).unwrap();
-        let tid = (time.subsec_nanos() >> 16) as u16;
-
-        let packet = Dns {
-            transaction_id: tid,
-            flags: 0x0100,
-            queries: vec![DnsQuery {
-                name: host.to_string(),
-                q_type: 0x0001,
-                q_class: 0x0001,
-            }],
-            answers: vec![]
-        };
-
-        let packet_data = packet.compile();
-
-        let my_ip = Ipv4Addr::new(ip[0], ip[1], ip[2], ip[3]);
-        let dns_ip = Ipv4Addr::new(dns[0], dns[1], dns[2], dns[3]);
-        let socket = UdpSocket::bind(&SocketAddr::V4(SocketAddrV4::new(my_ip, 0)))?;
-        socket.set_read_timeout(Some(Duration::new(5, 0)))?;
-        socket.set_write_timeout(Some(Duration::new(5, 0)))?;
-        socket.connect(&SocketAddr::V4(SocketAddrV4::new(dns_ip, 53)))?;
-        socket.send(&packet_data)?;
-
-        let mut buf = [0; 65536];
-        let count = socket.recv(&mut buf)?;
-
-        match Dns::parse(&buf[.. count]) {
-            Ok(response) => {
-                let mut addrs = vec![];
-                for answer in response.answers.iter() {
-                    if answer.a_type == 0x0001 && answer.a_class == 0x0001
-                       && answer.data.len() == 4
-                    {
-                        let answer_ip = Ipv4Addr::new(answer.data[0],
-                                                      answer.data[1],
-                                                      answer.data[2],
-                                                      answer.data[3]);
-                        addrs.push(SocketAddr::V4(SocketAddrV4::new(answer_ip, 0)));
-                    }
+impl<'a> TryFrom<&'a str> for LookupHost {
+    type Error = io::Error;
+
+    fn try_from(s: &str) -> io::Result<LookupHost> {
+        macro_rules! try_opt {
+            ($e:expr, $msg:expr) => (
+                match $e {
+                    Some(r) => r,
+                    None => return Err(io::Error::new(io::ErrorKind::InvalidInput,
+                                                      $msg)),
                 }
-                Ok(LookupHost(addrs.into_iter()))
-            },
-            Err(_err) => Err(Error::from_raw_os_error(EINVAL))
+            )
+        }
+
+        // split the string by ':' and convert the second part to u16
+        let mut parts_iter = s.rsplitn(2, ':');
+        let port_str = try_opt!(parts_iter.next(), "invalid socket address");
+        let host = try_opt!(parts_iter.next(), "invalid socket address");
+        let port: u16 = try_opt!(port_str.parse().ok(), "invalid port value");
+
+        (host, port).try_into()
+    }
+}
+
+impl<'a> TryFrom<(&'a str, u16)> for LookupHost {
+    type Error = io::Error;
+
+    fn try_from((host, port): (&'a str, u16)) -> io::Result<LookupHost> {
+        let mut ip_string = String::new();
+        File::open("/etc/net/ip")?.read_to_string(&mut ip_string)?;
+        let ip: Vec<u8> = ip_string.trim().split('.').map(|part| part.parse::<u8>()
+                                   .unwrap_or(0)).collect();
+
+        let mut dns_string = String::new();
+        File::open("/etc/net/dns")?.read_to_string(&mut dns_string)?;
+        let dns: Vec<u8> = dns_string.trim().split('.').map(|part| part.parse::<u8>()
+                                     .unwrap_or(0)).collect();
+
+        if ip.len() == 4 && dns.len() == 4 {
+            let time = time::SystemTime::now().duration_since(time::UNIX_EPOCH).unwrap();
+            let tid = (time.subsec_nanos() >> 16) as u16;
+
+            let packet = Dns {
+                transaction_id: tid,
+                flags: 0x0100,
+                queries: vec![DnsQuery {
+                    name: host.to_string(),
+                    q_type: 0x0001,
+                    q_class: 0x0001,
+                }],
+                answers: vec![]
+            };
+
+            let packet_data = packet.compile();
+
+            let my_ip = Ipv4Addr::new(ip[0], ip[1], ip[2], ip[3]);
+            let dns_ip = Ipv4Addr::new(dns[0], dns[1], dns[2], dns[3]);
+            let socket = UdpSocket::bind(Ok(&SocketAddr::V4(SocketAddrV4::new(my_ip, 0))))?;
+            socket.set_read_timeout(Some(Duration::new(5, 0)))?;
+            socket.set_write_timeout(Some(Duration::new(5, 0)))?;
+            socket.connect(Ok(&SocketAddr::V4(SocketAddrV4::new(dns_ip, 53))))?;
+            socket.send(&packet_data)?;
+
+            let mut buf = [0; 65536];
+            let count = socket.recv(&mut buf)?;
+
+            match Dns::parse(&buf[.. count]) {
+                Ok(response) => {
+                    let mut addrs = vec![];
+                    for answer in response.answers.iter() {
+                        if answer.a_type == 0x0001 && answer.a_class == 0x0001
+                           && answer.data.len() == 4
+                        {
+                            let answer_ip = Ipv4Addr::new(answer.data[0],
+                                                          answer.data[1],
+                                                          answer.data[2],
+                                                          answer.data[3]);
+                            addrs.push(SocketAddr::V4(SocketAddrV4::new(answer_ip, 0)));
+                        }
+                    }
+                    Ok(LookupHost(addrs.into_iter(), port))
+                },
+                Err(_err) => Err(Error::from_raw_os_error(EINVAL))
+            }
+        } else {
+            Err(Error::from_raw_os_error(EINVAL))
         }
-    } else {
-        Err(Error::from_raw_os_error(EINVAL))
     }
 }
 

src/libstd/sys/redox/net/tcp.rs

@@ -24,8 +24,8 @@ use super::{path_to_peer_addr, path_to_local_addr};
 pub struct TcpStream(File);
 
 impl TcpStream {
-    pub fn connect(addr: &SocketAddr) -> Result<TcpStream> {
-        let path = format!("tcp:{}", addr);
+    pub fn connect(addr: Result<&SocketAddr>) -> Result<TcpStream> {
+        let path = format!("tcp:{}", addr?);
         let mut options = OpenOptions::new();
         options.read(true);
         options.write(true);
@@ -180,8 +180,8 @@ impl IntoInner<File> for TcpStream {
 pub struct TcpListener(File);
 
 impl TcpListener {
-    pub fn bind(addr: &SocketAddr) -> Result<TcpListener> {
-        let path = format!("tcp:/{}", addr);
+    pub fn bind(addr: Result<&SocketAddr>) -> Result<TcpListener> {
+        let path = format!("tcp:/{}", addr?);
         let mut options = OpenOptions::new();
         options.read(true);
         options.write(true);

src/libstd/sys/redox/net/udp.rs

@@ -25,8 +25,8 @@ use super::{path_to_peer_addr, path_to_local_addr};
 pub struct UdpSocket(File, UnsafeCell<Option<SocketAddr>>);
 
 impl UdpSocket {
-    pub fn bind(addr: &SocketAddr) -> Result<UdpSocket> {
-        let path = format!("udp:/{}", addr);
+    pub fn bind(addr: Result<&SocketAddr>) -> Result<UdpSocket> {
+        let path = format!("udp:/{}", addr?);
         let mut options = OpenOptions::new();
         options.read(true);
         options.write(true);
@@ -37,8 +37,8 @@ impl UdpSocket {
         unsafe { &mut *(self.1.get()) }
     }
 
-    pub fn connect(&self, addr: &SocketAddr) -> Result<()> {
-        unsafe { *self.1.get() = Some(*addr) };
+    pub fn connect(&self, addr: Result<&SocketAddr>) -> Result<()> {
+        unsafe { *self.1.get() = Some(*addr?) };
         Ok(())
     }