Fix un-acked backlog coordinatin bug

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3133 42af7a65-404d-4744-a932-0658087f49c3

ChangeLog

@@ -1347,6 +1347,12 @@
 	  fixed that is needed by all Cortex-M3 NuttX users.
 	* configs/olimex-lpc1766stk/thttpd - Add a THTTPD configuration for the
 	  Olimex LPC2766-STK board.
+	* net/uip/uip_tcpappsend.c - Correct an important logic bug in some uIP state
+	  data the is used to manage retransmissions.  The uIP logic was incompatible
+	  with the retransmission logic of net/send.c in one place.  The final error
+	  was that the final packet in a sequence of packets was too large!  In the
+	  THTTPD example, this would leave some garbage at the bottom of the display
+	  (or worse).  I don't know why I haven't see this bug before???
 
 
 

Documentation/NuttX.html

@@ -8,7 +8,7 @@
   <tr align="center" bgcolor="#e4e4e4">
     <td>
       <h1><big><font color="#3c34ec"><i>NuttX RTOS</i></font></big></h1>
-      <p>Last Updated: November 23, 2010</p>
+      <p>Last Updated: November 25, 2010</p>
     </td>
   </tr>
 </table>
@@ -1996,6 +1996,12 @@ nuttx-5.14 2010-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
 	  fixed that is needed by all Cortex-M3 NuttX users.
 	* configs/olimex-lpc1766stk/thttpd - Add a THTTPD configuration for the
 	  Olimex LPC2766-STK board.
+	* net/uip/uip_tcpappsend.c - Correct an important logic bug in some uIP state
+	  data the is used to manage retransmissions.  The uIP logic was incompatible
+	  with the retransmission logic of net/send.c in one place.  The final error
+	  was that the final packet in a sequence of packets was too large!  In the
+	  THTTPD example, this would leave some garbage at the bottom of the display
+	  (or worse).  I don't know why I haven't see this bug before???
 
 pascal-2.1 2010-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
 

configs/olimex-lpc1766stk/thttpd/defconfig

@@ -206,6 +206,7 @@ CONFIG_PHY_AUTONEG=y
 CONFIG_PHY_SPEED100=n
 CONFIG_PHY_FDUPLEX=y
 CONFIG_NET_REGDEBUG=n
+
 #
 # General build options
 #
@@ -779,7 +780,7 @@ CONFIG_THTTPD_URLPATTERN=n
 #
 # Additional settings for examples/thttpd
 #
-CONFIG_EXAMPLE_THTTPD_NOMAC=n
+CONFIG_EXAMPLE_THTTPD_NOMAC=y
 CONFIG_EXAMPLE_THTTPD_DRIPADDR=(10<<24|0<<16|0<<8|1)
 CONFIG_EXAMPLE_THTTPD_NETMASK=(255<<24|255<<16|255<<8|0)
 

examples/thttpd/main.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * examples/thttpd/main.c
  *
- *   Copyright (C) 2009 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009-2010 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
   * Redistribution and use in source and binary forms, with or without
@@ -158,7 +158,7 @@ void user_initialize(void)
 int user_start(int argc, char *argv[])
 {
   struct in_addr addr;
-#ifdef CONFIG_EXAMPLE_UIP_NOMAC
+#ifdef CONFIG_EXAMPLE_THTTPD_NOMAC
   uint8_t mac[IFHWADDRLEN];
 #endif
   char *thttpd_argv = "thttpd";
@@ -166,7 +166,7 @@ int user_start(int argc, char *argv[])
 
 /* Many embedded network interfaces must have a software assigned MAC */
 
-#ifdef CONFIG_EXAMPLE_UIP_NOMAC
+#ifdef CONFIG_EXAMPLE_THTTPD_NOMAC
   message("Assigning MAC\n");
 
   mac[0] = 0x00;

net/send.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * net/send.c
  *
- *   Copyright (C) 2007-2009 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2010 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
  * Redistribution and use in source and binary forms, with or without

net/uip/uip_tcpappsend.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * net/uip/uip_tcpappsend.c
  *
- *   Copyright (C) 2007-2009 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2010 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
  * Adapted for NuttX from logic in uIP which also has a BSD-like license:
@@ -77,7 +77,9 @@
  * Name: uip_tcpappsend
  *
  * Description:
- *   Handle application response
+ *   Handle application or TCP protocol response.  If this function is called
+ *   with dev->d_sndlen > 0, then this is an application attempting to send
+ *   packet.
  *
  * Parameters:
  *   dev    - The device driver structure to use in the send operation
@@ -97,11 +99,12 @@ void uip_tcpappsend(struct uip_driver_s *dev, struct uip_conn *conn,
 {
   /* Handle the result based on the application response */
 
-  nllvdbg("result: %04x\n", result);
+  nllvdbg("result: %04x d_sndlen: %d conn->len: %d\n",
+          result, dev->d_sndlen, conn->len);
 
   /* Check for connection aborted */
 
-  if (result & UIP_ABORT)
+  if ((result & UIP_ABORT) != 0)
     {
       dev->d_sndlen = 0;
       conn->tcpstateflags = UIP_CLOSED;
@@ -112,10 +115,10 @@ void uip_tcpappsend(struct uip_driver_s *dev, struct uip_conn *conn,
 
   /* Check for connection closed */
 
-  else if (result & UIP_CLOSE)
+  else if ((result & UIP_CLOSE) != 0)
     {
       conn->tcpstateflags = UIP_FIN_WAIT_1;
-      conn->len = 1;
+      conn->len  = 1;
       conn->nrtx = 0;
       nllvdbg("TCP state: UIP_FIN_WAIT_1\n");
 
@@ -131,48 +134,34 @@ void uip_tcpappsend(struct uip_driver_s *dev, struct uip_conn *conn,
 
       if (dev->d_sndlen > 0)
         {
-          /* If the connection has acknowledged data, the contents of
+          /* If the connection has acknowledged data, the conn->len count
-           * the ->len variable should be discarded.
+           * should be discarded.
            */
 
-          if (result & UIP_ACKDATA)
+          if ((result & UIP_ACKDATA) != 0)
             {
               conn->len = 0;
             }
 
-          /* If the ->len variable is non-zero the connection has
+          /* Remember how much data we send out now so that we know
-           * already data in transit and cannot send anymore right
+           * when everything has been acknowledged.  No attempt is made
-           * now.
+           * here to keep track of how much outstanding, un-acked data
+           * there is.  That is handled in the TCP send() logic.  Here
+           * need the conn->len to be the same as the size of the packet
+           * to be sent.
+           *
+           * Just increment the amount of data sent.  This will be needed
+           * in sequence number calculations and we know that this is not
+           * a re-tranmission.  Retransmissions do not go through this path.
            */
 
-          if (conn->len == 0)
+          conn->len += dev->d_sndlen;
-            {
-              /* The application cannot send more than what is
-               * allowed by the mss (the minumum of the MSS and the
-               * available window).
-               */
 
-              if (dev->d_sndlen > conn->mss)
+          /* The application cannot send more than what is allowed by the
-                {
+           * MSS (the minumum of the MSS and the available window).
-                  dev->d_sndlen = conn->mss;
+           */
-                }
 
-              /* Remember how much data we send out now so that we
+          DEBUGASSERT(dev->d_sndlen <= conn->mss);
-               * know when everything has been acknowledged.
-               */
-
-              conn->len = dev->d_sndlen;
-            }
-          else
-            {
-              /* If the application already had unacknowledged data,
-               * we make sure that the application does not send
-               * (i.e., retransmit) out more than it previously sent
-               * out.
-               */
-
-              dev->d_sndlen = conn->len;
-            }
         }
 
       /* Then handle the rest of the operation just as for the rexmit case */
@@ -204,7 +193,8 @@ void uip_tcpappsend(struct uip_driver_s *dev, struct uip_conn *conn,
 void uip_tcprexmit(struct uip_driver_s *dev, struct uip_conn *conn,
                    uint16_t result)
 {
-  nllvdbg("result: %04x\n", result);
+  nllvdbg("result: %04x d_sndlen: %d conn->len: %d\n",
+          result, dev->d_sndlen, conn->len);
 
   dev->d_appdata = dev->d_snddata;
 
@@ -218,12 +208,12 @@ void uip_tcprexmit(struct uip_driver_s *dev, struct uip_conn *conn,
        * the IP and TCP headers.
        */
 
-      uip_tcpsend(dev, conn, TCP_ACK | TCP_PSH, conn->len + UIP_TCPIP_HLEN);
+      uip_tcpsend(dev, conn, TCP_ACK | TCP_PSH, dev->d_sndlen + UIP_TCPIP_HLEN);
     }
 
   /* If there is no data to send, just send out a pure ACK if one is requested`. */
 
-  else if (result & UIP_SNDACK)
+  else if ((result & UIP_SNDACK) != 0)
     {
       uip_tcpsend(dev, conn, TCP_ACK, UIP_TCPIP_HLEN);
     }