smoltcp-rs · Aug 21, 2017 · Aug 21, 2017 · Aug 21, 2017
Showing with 13 additions and 27 deletions.

+7 −13 README.md

+1 −13 examples/utils.rs

+5 −1 src/phy/sys/tap_interface.rs
diff --git a/README.md b/README.md
@@ -1,5 +1,4 @@
-smoltcp
-=======
+# smoltcp
 
 _smoltcp_ is a standalone, event-driven TCP/IP stack that is designed for bare-metal,
 real-time systems. Its design goals are simplicity and robustness. Its design anti-goals
@@ -11,8 +10,7 @@ and compiles on stable Rust 1.19 and later.
 
 [docs]: https://docs.rs/smoltcp/
 
-Features
---------
+## Features
 
 _smoltcp_ is missing many widely deployed features, whether by design or simply because
 no one implemented them yet. To set expectations right, both implemented and omitted
@@ -66,8 +64,7 @@ The TCP protocol is supported over IPv4. Server and client sockets are supported
     * Fast open is **not** supported.
   * Keepalive is **not** supported.
 
-Installation
-------------
+## Installation
 
 To use the _smoltcp_ library in your project, add the following to `Cargo.toml`:
 
@@ -127,14 +124,13 @@ or `BufWriter` is used, which are of course not available on heap-less systems.
 
 This feature is disabled by default.
 
-Hosted usage examples
----------------------
+## Hosted usage examples
 
 _smoltcp_, being a freestanding networking stack, needs to be able to transmit and receive
 raw frames. For testing purposes, we will use a regular OS, and run _smoltcp_ in
 a userspace process. Only Linux is supported (right now).
 
-On *nix OSes, transmiting and receiving raw frames normally requires superuser privileges, but
+On \*nix OSes, transmiting and receiving raw frames normally requires superuser privileges, but
 on Linux it is possible to create a _persistent tap interface_ that can be manipulated by
 a specific user:
 
@@ -250,8 +246,7 @@ Currently, netmasks are not implemented, and so the only address this example ca
 is the other endpoint of the tap interface, `192.168.1.100`. It cannot reach itself because
 packets entering a tap interface do not loop back.
 
-Bare-metal usage examples
--------------------------
+## Bare-metal usage examples
 
 Examples that use no services from the host OS are necessarily less illustrative than examples
 that do. Because of this, only one such example is provided.
@@ -281,8 +276,7 @@ is possible; otherwise, nothing at all will be displayed and no options are acce
 
 [wireshark]: https://wireshark.org
 
-License
--------
+## License
 
 _smoltcp_ is distributed under the terms of 0-clause BSD license.
 

diff --git a/examples/utils.rs b/examples/utils.rs
@@ -47,18 +47,6 @@ pub fn setup_logging(filter: &str) {
     })
 }
 
-struct Dispose;
-
-impl io::Write for Dispose {
-    fn write(&mut self, data: &[u8]) -> io::Result<usize> {
-        Ok(data.len())
-    }
-
-    fn flush(&mut self) -> io::Result<()> {
-        Ok(())
-    }
-}
-
 pub fn create_options() -> (Options, Vec<&'static str>) {
     let mut opts = Options::new();
     opts.optflag("h", "help", "print this help menu");
@@ -123,7 +111,7 @@ pub fn parse_middleware_options<D: Device>(matches: &mut Matches, device: D, loo
     if let Some(pcap_filename) = matches.opt_str("pcap") {
         pcap_writer = Box::new(File::create(pcap_filename).expect("cannot open file"))
     } else {
-        pcap_writer = Box::new(Dispose)
+        pcap_writer = Box::new(io::sink())
     }
 
     let seed = SystemTime::now().duration_since(UNIX_EPOCH).unwrap().subsec_nanos();

diff --git a/src/phy/sys/tap_interface.rs b/src/phy/sys/tap_interface.rs
@@ -37,7 +37,11 @@ impl TapInterfaceDesc {
             lower
         };
 
-        ifreq_ioctl(lower, &mut self.ifreq, imp::SIOCGIFMTU).map(|mtu| mtu as usize)
+        let mtu = ifreq_ioctl(lower, &mut self.ifreq, imp::SIOCGIFMTU).map(|mtu| mtu as usize);
+
+        unsafe { libc::close(lower); }
+
+        mtu
     }
 
     fn wait(&mut self, ms: u32) -> io::Result<bool> {