src/nal.rs

@@ -1,5 +1,5 @@
 use core::cell::RefCell;
-use core::convert::TryInto;
+use core::convert::TryFrom;
 use heapless::{consts, Vec};
 use embedded_nal as nal;
 use nal::nb;
@@ -40,8 +40,7 @@ where
     unused_handles: RefCell<Vec<net::socket::SocketHandle, consts::U16>>,
     time_ms: RefCell<u32>,
     last_update_instant: RefCell<Option<time::Instant<IntClock>>>,
-    clock: IntClock,
-    connection_timeout_ms: u32,
+    clock: IntClock
 }
 
 impl<'a, SPI, NSS, IntClock> NetworkStack<'a, SPI, NSS, IntClock>
@@ -50,12 +49,7 @@ where
     NSS: OutputPin,
     IntClock: time::Clock<T = u32>,
 {
-    pub fn new(
-        interface: NetworkInterface<SPI, NSS>,
-        sockets: net::socket::SocketSet<'a>,
-        clock: IntClock,
-        connection_timeout_ms: u32,
-    ) -> Self {
+    pub fn new(interface: NetworkInterface<SPI, NSS>, sockets: net::socket::SocketSet<'a>, clock: IntClock) -> Self {
         let mut unused_handles: Vec<net::socket::SocketHandle, consts::U16> = Vec::new();
         for socket in sockets.iter() {
             unused_handles.push(socket.handle()).unwrap();
@@ -68,55 +62,34 @@ where
             time_ms: RefCell::new(0),
             last_update_instant: RefCell::new(None),
             clock,
-            connection_timeout_ms,
         }
     }
 
-    // Initiate or advance the timer, and return the duration in ms as u32.
-    fn update(&self) -> Result<u32, NetworkError> {
-        let mut duration_ms: u32 = 0;
-        // Check if it is the first time the stack has updated the time itself
-        let now = match *self.last_update_instant.borrow() {
-            // If it is the first time, do not advance time
-            // Simply store the current instant to initiate time updating
-            None => self.clock.try_now().map_err(|_| NetworkError::TimeFault)?,
-            // If it was updated before, advance time and update last_update_instant
-            Some(instant) => {
-                // Calculate elapsed time
-                let now = self.clock.try_now().map_err(|_| NetworkError::TimeFault)?;
-                let mut duration = now.checked_duration_since(&instant);
-                // Normally, the wrapping clock should produce a valid duration.
-                // However, if `now` is earlier than `instant` (e.g. because the main 
-                // application cannot get a valid epoch time during initialisation, 
-                // we should still produce a duration that is just 1ms.
-                if duration.is_none() {
-                    self.time_ms.replace(0);
-                    duration = Some(Milliseconds(1_u32)
-                        .to_generic::<u32>(IntClock::SCALING_FACTOR)
-                        .map_err(|_| NetworkError::TimeFault)?);
+    // Include auto_time_update to allow Instant::now() to not be called
+    // Instant::now() is not safe to call in `init()` context
+    pub fn update(&self, auto_time_update: bool) -> Result<bool, NetworkError> {
+        if auto_time_update {
+            // Check if it is the first time the stack has updated the time itself
+            let now = match *self.last_update_instant.borrow() {
+                // If it is the first time, do not advance time
+                // Simply store the current instant to initiate time updating
+                None => self.clock.try_now().map_err(|_| NetworkError::TimeFault)?,
+                // If it was updated before, advance time and update last_update_instant
+                Some(instant) => {
+                    // Calculate elapsed time
+                    let now = self.clock.try_now().map_err(|_| NetworkError::TimeFault)?;
+                    let duration = now.checked_duration_since(&instant).ok_or(NetworkError::TimeFault)?;
+                    let duration_ms = time::duration::Milliseconds::<u32>::try_from(duration).map_err(|_| NetworkError::TimeFault)?;
+                    // Adjust duration into ms (note: decimal point truncated)
+                    self.advance_time(*duration_ms.integer());
+                    now
                 }
-                let duration_ms_time: Milliseconds<u32> = duration.unwrap().try_into()
-                    .map_err(|_| NetworkError::TimeFault)?;
-                duration_ms = *duration_ms_time.integer();
-                // Adjust duration into ms (note: decimal point truncated)
-                self.advance_time(duration_ms);
-                now
-            }
-        };
-        self.last_update_instant.replace(Some(now));
-        Ok(duration_ms)
-    }
-
-    fn advance_time(&self, duration_ms: u32) {
-        let time = self.time_ms.borrow().wrapping_add(duration_ms);
-        self.time_ms.replace(time);
-    }
-
-    // Poll on the smoltcp interface
-    fn poll(&self) -> Result<bool, NetworkError> {
+            };
+            self.last_update_instant.replace(Some(now));
+        }
         match self.network_interface.borrow_mut().poll(
             &mut self.sockets.borrow_mut(),
-            net::time::Instant::from_millis(*self.time_ms.borrow() as u32),
+            net::time::Instant::from_millis(*self.time_ms.borrow() as i64),
         ) {
             Ok(changed) => Ok(!changed),
             Err(_e) => {
@@ -125,6 +98,11 @@ where
         }
     }
 
+    pub fn advance_time(&self, duration: u32) {
+        let time = self.time_ms.try_borrow().unwrap().wrapping_add(duration);
+        self.time_ms.replace(time);
+    }
+
     fn get_ephemeral_port(&self) -> u16 {
         // Get the next ephemeral port
         let current_port = self.next_port.borrow().clone();
@@ -146,169 +124,122 @@ where
             Some(handle) => {
                 // Abort any active connections on the handle.
                 let mut sockets = self.sockets.borrow_mut();
-                let socket: &mut net::socket::TcpSocket = &mut *sockets.get(handle);
-                socket.abort();
+                let internal_socket: &mut net::socket::TcpSocket = &mut *sockets.get(handle);
+                internal_socket.abort();
                 Ok(handle)
             }
             None => Err(NetworkError::NoSocket),
         }
     }
 
+    // Ideally connect is only to be performed in `init()` of `main.rs`
+    // Calling `Instant::now()` of `rtic::cyccnt` would face correctness issue during `init()`
     fn connect(
         &self,
-        handle: Self::TcpSocket,
+        socket: Self::TcpSocket,
         remote: nal::SocketAddr,
     ) -> Result<Self::TcpSocket, Self::Error> {
-        {
-            // If the socket has already been connected, ignore the connection
-            // request silently.
+        let address = {
             let mut sockets = self.sockets.borrow_mut();
-            let socket: &mut net::socket::TcpSocket = &mut *sockets.get(handle);
-            if socket.state() == net::socket::TcpState::Established {
-                return Ok(handle)
+            let internal_socket: &mut net::socket::TcpSocket = &mut *sockets.get(socket);
+            // If we're already in the process of connecting, ignore the request silently.
+            if internal_socket.is_open() {
+                return Ok(socket);
             }
-        }
-
-        {
-            let mut sockets = self.sockets.borrow_mut();
-            let socket: &mut net::socket::TcpSocket = &mut *sockets.get(handle);
-            // abort() instead of close() prevents TcpSocket::connect() from
-            // raising an error
-            socket.abort();
             match remote.ip() {
                 nal::IpAddr::V4(addr) => {
                     let address =
                         net::wire::Ipv4Address::from_bytes(&addr.octets()[..]);
-                    socket
+                    internal_socket
                         .connect((address, remote.port()), self.get_ephemeral_port())
                         .map_err(|_| NetworkError::ConnectionFailure)?;
                     net::wire::IpAddress::Ipv4(address)
-                },
+                }
                 nal::IpAddr::V6(addr) => {
-                    let address =
-                        net::wire::Ipv6Address::from_parts(&addr.segments()[..]);
-                    socket
-                        .connect((address, remote.port()), self.get_ephemeral_port())
+                    let address = net::wire::Ipv6Address::from_parts(&addr.segments()[..]);
+                    internal_socket.connect((address, remote.port()), self.get_ephemeral_port())
                         .map_err(|_| NetworkError::ConnectionFailure)?;
                     net::wire::IpAddress::Ipv6(address)
                 }
             }
         };
         // Blocking connect
-        // Loop to wait until the socket is staying established or closed,
-        // or the connection attempt has timed out.
-        let mut timeout_ms: u32 = 0;
         loop {
-            {
-                let mut sockets = self.sockets.borrow_mut();
-                let socket: &mut net::socket::TcpSocket = &mut *sockets.get(handle);
-                // TCP state at ESTABLISHED means there is connection, so
-                // simply return the socket.
-                if socket.state() == net::socket::TcpState::Established {
-                    return Ok(handle)
-                }
-                // TCP state at CLOSED implies that the remote rejected connection;
-                // In this case, abort the connection, and then return the socket
-                // for re-connection in the future.
-                if socket.state() == net::socket::TcpState::Closed {
-                    socket.abort();
-                    // TODO: Return Err(), but would require changes in quartiq/minimq
-                    return Ok(handle)
+            match self.is_connected(&socket) {
+                Ok(true) => break,
+                _ => {
+                    let mut sockets = self.sockets.borrow_mut();
+                    let internal_socket: &mut net::socket::TcpSocket = &mut *sockets.get(socket);
+                    // If the connect got ACK->RST, it will end up in Closed TCP state
+                    // Perform reconnection in this case
+                    if internal_socket.state() == net::socket::TcpState::Closed {
+                        internal_socket.close();
+                        internal_socket
+                            .connect((address, remote.port()), self.get_ephemeral_port())
+                            .map_err(|_| NetworkError::ConnectionFailure)?;
+                    }
                 }
             }
-            
-            // Any TCP states other than CLOSED and ESTABLISHED are considered
-            // "transient", so this function should keep waiting and let smoltcp poll
-            // (e.g. for handling echo reqeust/reply) at the same time.
-            timeout_ms += self.update()?;
-            self.poll()?;
-
-            // Time out, and return the socket for re-connection in the future.
-            if timeout_ms > self.connection_timeout_ms {
-                // TODO: Return Err(), but would require changes in quartiq/minimq
-                return Ok(handle)
+            // Avoid using Instant::now() and Advance time manually
+            self.update(false)?;
+            {
+                self.advance_time(1);
             }
         }
+        Ok(socket)
     }
 
-    fn is_connected(&self, handle: &Self::TcpSocket) -> Result<bool, Self::Error> {
+    fn is_connected(&self, socket: &Self::TcpSocket) -> Result<bool, Self::Error> {
         let mut sockets = self.sockets.borrow_mut();
-        let socket: &mut net::socket::TcpSocket = &mut *sockets.get(*handle);
-        Ok(socket.state() == net::socket::TcpState::Established)
+        let socket: &mut net::socket::TcpSocket = &mut *sockets.get(*socket);
+        Ok(socket.may_send() && socket.may_recv())
     }
 
-    fn write(&self, handle: &mut Self::TcpSocket, buffer: &[u8]) -> nb::Result<usize, Self::Error> {
-        let mut write_error = false;
+    fn write(&self, socket: &mut Self::TcpSocket, buffer: &[u8]) -> nb::Result<usize, Self::Error> {
         let mut non_queued_bytes = &buffer[..];
         while non_queued_bytes.len() != 0 {
             let result = {
                 let mut sockets = self.sockets.borrow_mut();
-                let socket: &mut net::socket::TcpSocket = &mut *sockets.get(*handle);
+                let socket: &mut net::socket::TcpSocket = &mut *sockets.get(*socket);
                 let result = socket.send_slice(non_queued_bytes);
                 result
             };
             match result {
                 Ok(num_bytes) => {
-                    // If the buffer is completely filled, close the socket and
-                    // return an error
-                    if num_bytes == 0 {
-                        write_error = true;
-                        break;
-                    }
                     // In case the buffer is filled up, push bytes into ethernet driver
                     if num_bytes != non_queued_bytes.len() {
-                        self.update()?;
-                        self.poll()?;
+                        self.update(true)?;
                     }
                     // Process the unwritten bytes again, if any
                     non_queued_bytes = &non_queued_bytes[num_bytes..]
                 }
-                Err(_) => {
-                    write_error = true;
-                    break;
-                }
+                Err(_) => return Err(nb::Error::Other(NetworkError::WriteFailure)),
             }
         }
-        if write_error {
-            // Close the socket to push it back to the array, for
-            // re-opening the socket in the future
-            self.close(*handle)?;
-            return Err(nb::Error::Other(NetworkError::WriteFailure))
-        }   
         Ok(buffer.len())
     }
 
     fn read(
         &self,
-        handle: &mut Self::TcpSocket,
+        socket: &mut Self::TcpSocket,
         buffer: &mut [u8],
     ) -> nb::Result<usize, Self::Error> {
         // Enqueue received bytes into the TCP socket buffer
-        self.update()?;
-        self.poll()?;
-        {
-            let mut sockets = self.sockets.borrow_mut();
-            let socket: &mut net::socket::TcpSocket = &mut *sockets.get(*handle);
-            let result = socket.recv_slice(buffer);
-            match result {
-                Ok(num_bytes) => { return Ok(num_bytes) },
-                Err(_) => {},
-            }
+        self.update(true)?;
+        let mut sockets = self.sockets.borrow_mut();
+        let socket: &mut net::socket::TcpSocket = &mut *sockets.get(*socket);
+        let result = socket.recv_slice(buffer);
+        match result {
+            Ok(num_bytes) => Ok(num_bytes),
+            Err(_) => Err(nb::Error::Other(NetworkError::ReadFailure)),
         }
-        // Close the socket to push it back to the array, for
-        // re-opening the socket in the future
-        self.close(*handle)?;
-        Err(nb::Error::Other(NetworkError::ReadFailure))
     }
 
-    fn close(&self, handle: Self::TcpSocket) -> Result<(), Self::Error> {
+    fn close(&self, socket: Self::TcpSocket) -> Result<(), Self::Error> {
         let mut sockets = self.sockets.borrow_mut();
-        let socket: &mut net::socket::TcpSocket = &mut *sockets.get(handle);
-        socket.close();
-        let mut unused_handles = self.unused_handles.borrow_mut();
-        if unused_handles.iter().find(|&x| *x == handle).is_none() {
-            unused_handles.push(handle).unwrap();
-        }
+        let internal_socket: &mut net::socket::TcpSocket = &mut *sockets.get(socket);
+        internal_socket.close();
+        self.unused_handles.borrow_mut().push(socket).unwrap();
         Ok(())
     }
 }