Corrected a bug in the buffering of TCP data

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@1289 42af7a65-404d-4744-a932-0658087f49c3

ChangeLog

@@ -572,4 +572,8 @@
 	  to refill the input buffer. The old behavior (read full blocks) might be useful in other
 	  contexts, so it is still available within the driver as a configuration option.
 	* Implement poll() and select() support for TCP/IP sockets
+	* Fixed an important bug in the TCP/IP buffering logic.  When TCP/IP read-ahead is enabled
+	  and not recv() is in-place when a TCP/IP packet is received, the packet is placed into
+	  a read-ahead buffer.  However, the old contents of the read-ahead buffer were not being
+	  cleared and old data would contaminate the newly received buffer.
 

Documentation/NuttX.html

@@ -1208,6 +1208,10 @@ nuttx-0.3.19 2008-xx-xx Gregory Nutt <spudmonkey@racsa.co.cr>
 	  to refill the input buffer. The old behavior (read full blocks) might be useful in other
 	  contexts, so it is still available within the driver as a configuration option.
 	* Implement poll() and select() support for TCP/IP sockets
+	* Fixed an important bug in the TCP/IP buffering logic.  When TCP/IP read-ahead is enabled
+	  and not recv() is in-place when a TCP/IP packet is received, the packet is placed into
+	  a read-ahead buffer.  However, the old contents of the read-ahead buffer were not being
+	  cleared and old data would contaminate the newly received buffer.
 
 pascal-0.1.3 2008-xx-xx Gregory Nutt <spudmonkey@racsa.co.cr>
 

net/uip/uip-tcpcallback.c

@@ -172,6 +172,7 @@ uip_dataevent(struct uip_driver_s *dev, struct uip_conn *conn, uint16 flags)
 
           if (readahead2)
             {
+              readahead2->rh_nbytes = 0;
               (void)uip_readahead(readahead2, buf, buflen);
 
               /* Save the readahead buffer in the connection structure where