Fix confusion in listening socket vs accepted sockets

git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@395 7fd9a85b-ad96-42d3-883c-3090e2eb8679

nuttx/examples/README.txt

@@ -46,4 +46,18 @@ examples/null
 ^^^^^^^^^^^^^
 
   This is the do nothing application.  It is only used for bringing
-  up new NuttX architectures
+  up new NuttX architectures.
+
+examples/uip
+^^^^^^^^^^^^
+
+  This is a port of uIP example application.  It includes
+  conditionally compiled logic to exercise the uIP webserver,
+  webclient, telnet, smtp, dncpc, and resolver.
+
+examples/netttest
+^^^^^^^^^^^^^^^^^
+
+  This is a simple network test for verifying client- and server-
+  functionality in a TCP/IP connection.
+

nuttx/include/net/uip/uip.h

@@ -572,25 +572,13 @@ extern int uip_tcpconnect(struct uip_conn *conn, const struct sockaddr_in6 *addr
 extern int uip_tcpconnect(struct uip_conn *conn, const struct sockaddr_in *addr);
 #endif
 
-/* Start listening to the specified port.
- *
- * Note: Since this function expects the port number in network byte
- * order, a conversion using HTONS() or htons() is necessary.
- *
- * port A 16-bit port number in network byte order.
- */
+/* Start listening to the port bound to the specified TCP connection */
 
-extern int uip_listen(uint16 port);
+extern int uip_listen(struct uip_conn *conn);
 
-/* Stop listening to the specified port.
- *
- * Note: Since this function expects the port number in network byte
- * order, a conversion using HTONS() or htons() is necessary.
- *
- * port A 16-bit port number in network byte order.
- */
+/* Stop listening to the port bound to the specified TCP connection */
 
-extern int uip_unlisten(uint16 port);
+extern int uip_unlisten(struct uip_conn *conn);
 
 /* Check if a connection has outstanding (i.e., unacknowledged) data */
 

nuttx/net/listen.c

@@ -126,9 +126,9 @@ int listen(int sockfd, int backlog)
    * is called; and someday should enable post() or select() logic.
    */
   
-	uip_listen(conn->lport);
+  uip_listen(conn);
   psock->s_flags |= _SF_LISTENING;
-	return OK;
+  return OK;
 
 errout:
   *get_errno_ptr() = err;

nuttx/net/uip/uip-listen.c

@@ -57,7 +57,7 @@
 
 /* The uip_listenports list all currently listening ports. */
 
-static uint16 uip_listenports[CONFIG_NET_MAX_LISTENPORTS];
+static struct uip_conn *uip_listenports[CONFIG_NET_MAX_LISTENPORTS];
 
 /****************************************************************************
  * Private Functions
@@ -84,7 +84,7 @@ void uip_listeninit(void)
   int ndx;
   for (ndx = 0; ndx < CONFIG_NET_MAX_LISTENPORTS; ndx++)
     {
-      uip_listenports[ndx] = 0;
+      uip_listenports[ndx] = NULL;
     }
 }
 
@@ -92,14 +92,14 @@ void uip_listeninit(void)
  * Function: uip_unlisten
  *
  * Description:
- *   Stop listening on a port
+ *   Stop listening to the port bound to the specified TCP connection
  *
  * Assumptions:
  *   Called from normal user code.
  *
  ****************************************************************************/
 
-int uip_unlisten(uint16 port)
+int uip_unlisten(struct uip_conn *conn)
 {
   irqstate_t flags;
   int ndx;
@@ -108,13 +108,14 @@ int uip_unlisten(uint16 port)
   flags = irqsave();
   for (ndx = 0; ndx < CONFIG_NET_MAX_LISTENPORTS; ndx++)
     {
-      if (uip_listenports[ndx] == port)
+      if (uip_listenports[ndx] == conn)
         {
-          uip_listenports[ndx] = 0;
+          uip_listenports[ndx] = NULL;
           ret = OK;
           break;
         }
     }
+
   irqrestore(flags);
   return ret;
 }
@@ -123,29 +124,58 @@ int uip_unlisten(uint16 port)
  * Function: uip_listen
  *
  * Description:
- *   Start listening on a port
+ *   Start listening to the port bound to the specified TCP connection
  *
  * Assumptions:
  *   Called from normal user code.
  *
  ****************************************************************************/
 
-int uip_listen(uint16 port)
+int uip_listen(struct uip_conn *conn)
 {
   irqstate_t flags;
   int ndx;
-  int ret = -ENOBUFS;
+  int ret;
+
+  /* This must be done with interrupts disabled because the listener table
+   * is accessed from interrupt level as well.
+   */
 
   flags = irqsave();
-  for (ndx = 0; ndx < CONFIG_NET_MAX_LISTENPORTS; ndx++)
+
+  /* First, check if there is already a socket listening on this port */
+
+  if (uip_islistener(conn->lport))
     {
-      if (uip_listenports[ndx] == 0)
+      /* Yes, then we must refuse this request */
+
+      ret = -EADDRINUSE;
+    }
+  else
+    {
+      /* Otherwise, save a reference to the connection structure in the
+       * "listener" list.
+       */
+
+      ret = -ENOBUFS; /* Assume failure */
+
+      /* Search all slots until an available slot is found */
+
+      for (ndx = 0; ndx < CONFIG_NET_MAX_LISTENPORTS; ndx++)
         {
-          uip_listenports[ndx] = port;
-          ret = OK;
-          break;
+          /* Is the next slot available? */
+
+          if (!uip_listenports[ndx])
+            {
+              /* Yes.. we found it */
+
+              uip_listenports[ndx] = conn;
+              ret = OK;
+              break;
+            }
         }
     }
+
   irqrestore(flags);
   return ret;
 }
@@ -164,13 +194,26 @@ int uip_listen(uint16 port)
 boolean uip_islistener(uint16 portno)
 {
   int ndx;
+
+  /* Examine each connection structure in each slot of the listener list */
+
   for (ndx = 0; ndx < CONFIG_NET_MAX_LISTENPORTS; ndx++)
     {
-      if (uip_listenports[ndx] == portno)
+      /* Is this slot assigned?  If so, does the connection have the same
+       * local port number?
+       */
+
+      struct uip_conn *conn = uip_listenports[ndx];
+      if (conn && conn->lport == portno)
         {
+          /* Yes.. we found a listener on this port */
+
           return TRUE;
         }
     }
+
+  /* No listener for this port */
+
   return FALSE;
 }