more fixes in the TELNET code

TODO.txt

@@ -1,9 +1,13 @@
-- the aborted/timedout/closed condition in elua_uip_appcall is called more than once for the same socket ? add logs and check
+x the aborted/timedout/closed condition in elua_uip_appcall is called more than once for the same socket ? add logs and check
+  x this seems to be a problem with PuTTY only, Windows and Linux 'telnet' commands do not exhibit this behaviour
 - does the telnet socket need to be buffered? might be if there are clients that send data char by char (check Windows)
 - test telnet thoroughly
 - what happens with a TCP socket state when the connection is closed from the remote end for whatever reason? are the buffers freed?
 - check if calling the uIP mainloop at only 2Hz is the right thing to do; doesn't this violate uIP's internal timeout mechanism?
 - is uip_forced_poll used properly in uip.c ? what's the point of forced_poll anyway ? 
+- add per socket callbacks for remote close events (and maybe other error conditions)
+- add C/Lua interrupts for different socket events: data received, socket closed, network link up/down ...
+- the socket without buffers OR callback should probably be completely removed; the Lua side will only be able to create sockets with buffers?
 - clean elua_uip.c after testing:
   - remove #ifdef/#define BUILD_CON_TCP at start of file
   - uncomment #ifndef in elua_uip_log

src/elua_uip.c

@@ -33,7 +33,6 @@ static p_elua_net_state_cb elua_uip_state_cb;
 
 #define TCPIP_LOG_BUFSIZE     80
 #ifdef TCPIP_LOGS
-const char *elua_uip_log_header = "[elua_uip] ";
 
 static void elua_uip_log( const char *fmt, ... )
 {
@@ -41,15 +40,12 @@ static void elua_uip_log( const char *fmt, ... )
 
   va_start( ap, fmt );
 #ifndef BUILD_CON_TCP
-  printf( elua_uip_log_header );
   vprintf( fmt, ap );
 #else // #ifndef BUILD_CON_TCP
   unsigned i;
   char dstr[ TCPIP_LOG_BUFSIZE + 1 ];
 
   vsnprintf( dstr, TCPIP_LOG_BUFSIZE, fmt, ap );
-  for( i = 0; i < strlen( elua_uip_log_header ); i ++ )
-    platform_uart_send( CON_UART_ID, elua_uip_log_header[ i ] );
   for( i = 0; i < strlen( dstr ); i ++ )
   {
     if( dstr[ i ] == '\n' )

src/newlib/stdtcp.c

@@ -30,9 +30,9 @@ static unsigned stdh_telnet_handle_input( char *buf, unsigned buflen )
 {
   int skip;
   char *pdata = buf;
-  unsigned datalen = buflen;
+  int datalen = buflen;
 
-  while( ( pdata < buf + buflen ) && datalen )
+  while( ( pdata < buf + buflen ) && datalen > 0 )
   {
     if( *pdata != TELNET_IAC_CHAR ) // regular char, skip it
       pdata ++;
@@ -52,6 +52,8 @@ static unsigned stdh_telnet_handle_input( char *buf, unsigned buflen )
       }
       else if( pdata[ 1 ] == TELNET_EOF ) // replace with EOF, remove one char from input
         *pdata ++ = STD_CTRLZ_CODE;
+      else // assume that next character must be consumed anyway
+        skip = 2;
       datalen -= skip;
       memmove( pdata, pdata + skip, datalen - ( pdata - buf ) );
     }