TCP write buffering: Fix an error in the trim logic

include/nuttx/net/uip/uip-tcp.h

@@ -134,7 +134,9 @@
 #  define WRB_IOB(wrb)            ((wrb)->wb_iob)
 #  define WRB_COPYOUT(wrb,dest,n) (iob_copyout(dest,(wrb)->wb_iob,(n),0))
 #  define WRB_COPYIN(wrb,src,n)   (iob_copyin((wrb)->wb_iob,src,(n),0))
-#  define WRB_TRIM(wrb,n)         (iob_trimhead((wrb)->wb_iob,(n)))
+
+#  define WRB_TRIM(wrb,n) \
+  do { (wrb)->wb_iob = iob_trimhead((wrb)->wb_iob,(n)); } while (0)
 
 #ifdef CONFIG_DEBUG
 #  define WRB_DUMP(msg,wrb)       tcp_writebuffer_dump(msg,wrb)

net/iob/Kconfig

@@ -42,4 +42,15 @@ config IOB_NCHAINS
 		I/O buffer chain containers that also carry a payload of usage
 		specific information.
 
+config NET_IOB_DEBUG
+	bool "Force I/O buffer debug"
+	default n
+	depends on DEBUG
+	---help---
+		This option will force debug output from I/O buffer logic,
+		even without network debug output.  This is not normally something
+		that would want to do but is convenient if you are debugging the
+		I/O buffer logic and do not want to get overloaded with other
+		network-related debug output.
+
 endif # NET_IOB

net/iob/iob_add_queue.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <assert.h>
 #include <errno.h>
 #include <debug.h>

net/iob/iob_alloc.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <semaphore.h>
 #include <assert.h>
 

net/iob/iob_alloc_qentry.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <semaphore.h>
 #include <assert.h>
 

net/iob/iob_clone.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <string.h>
 #include <assert.h>
 #include <errno.h>

net/iob/iob_concat.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <string.h>
 
 #include <nuttx/net/iob.h>

net/iob/iob_contig.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <string.h>
 #include <assert.h>
 #include <errno.h>

net/iob/iob_copyin.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <stdint.h>
 #include <string.h>
 #include <errno.h>
@@ -91,13 +98,14 @@ int iob_copyin(FAR struct iob_s *iob, FAR const uint8_t *src,
   unsigned int ncopy;
   unsigned int avail;
 
+  nllvdbg("iob=%p len=%u offset=%u\n", iob, len, offset);
   DEBUGASSERT(iob && src);
 
   /* The offset must applied to data that is already in the I/O buffer chain */
 
   if (offset > iob->io_pktlen)
     {
-      ndbg("ERROR: offset is past the end of data: %d > %d\n",
+      ndbg("ERROR: offset is past the end of data: %u > %u\n",
            offset, iob->io_pktlen);
       return -ESPIPE;
     }
@@ -123,6 +131,8 @@ int iob_copyin(FAR struct iob_s *iob, FAR const uint8_t *src,
       dest  = &iob->io_data[iob->io_offset + offset];
       avail = iob->io_len - offset;
 
+      nllvdbg("iob=%p avail=%u len=%u next=%p\n", iob, avail, len, next);
+
       /* Will the rest of the copy fit into this buffer, overwriting
        * existing data.
        */
@@ -146,7 +156,7 @@ int iob_copyin(FAR struct iob_s *iob, FAR const uint8_t *src,
 
               /* Yes.. We can extend this buffer to the up to the very end. */
 
-              maxlen  = CONFIG_IOB_BUFSIZE - iob->io_offset;
+              maxlen = CONFIG_IOB_BUFSIZE - iob->io_offset;
 
               /* This is the new buffer length that we need.  Of course,
                * clipped to the maximum possible size in this buffer.
@@ -178,6 +188,8 @@ int iob_copyin(FAR struct iob_s *iob, FAR const uint8_t *src,
       /* Copy from the user buffer to the I/O buffer.  */
 
       memcpy(dest, src, ncopy);
+      nllvdbg("iob=%p, Copy %u bytes, new len=%u\n",
+              iob, ncopy, iob->io_len);
 
       /* Adjust the total length of the copy and the destination address in
        * the user buffer.
@@ -204,6 +216,7 @@ int iob_copyin(FAR struct iob_s *iob, FAR const uint8_t *src,
           /* Add the new, empty I/O buffer to the end of the buffer chain. */
 
           iob->io_flink = next;
+          nllvdbg("iob=%p added to the chain\n", iob);
         }
 
       iob = next;

net/iob/iob_copyout.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <stdint.h>
 #include <string.h>
 #include <assert.h>

net/iob/iob_free.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <semaphore.h>
 #include <assert.h>
 

net/iob/iob_free_chain.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <nuttx/arch.h>
 #include <nuttx/net/iob.h>
 

net/iob/iob_free_qentry.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <semaphore.h>
 #include <assert.h>
 

net/iob/iob_free_queue.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <assert.h>
 
 #include <nuttx/net/iob.h>

net/iob/iob_initialize.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <stdbool.h>
 #include <semaphore.h>
 

net/iob/iob_pack.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <string.h>
 
 #include <nuttx/net/iob.h>

net/iob/iob_remove_queue.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <debug.h>
 
 #include <nuttx/net/iob.h>

net/iob/iob_trimhead.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <assert.h>
 #include <debug.h>
 
@@ -82,23 +89,22 @@
 FAR struct iob_s *iob_trimhead(FAR struct iob_s *iob, unsigned int trimlen)
 {
   uint16_t pktlen;
-  unsigned int len;
 
-  nllvdbg("iob=%p pktlen=%d trimlen=%d\n", iob, iob->io_pktlen, trimlen);
+  nllvdbg("iob=%p trimlen=%d\n", iob, trimlen);
 
   if (iob && trimlen > 0)
     {
       /* Trim from the head of the I/IO buffer chain */
 
       pktlen = iob->io_pktlen;
-      len    = trimlen;
+      while (trimlen > 0 && iob != NULL)
-
-      while (len > 0 && iob != NULL)
         {
           /* Do we trim this entire I/O buffer away? */
 
-          nllvdbg("iob=%p len=%d vs %d\n", iob, iob->io_len, len);
+          nllvdbg("iob=%p io_len=%d pktlen=%d trimlen=%d\n",
-          if (iob->io_len <= len)
+                  iob, iob->io_len, pktlen, trimlen);
+
+          if (iob->io_len <= trimlen)
             {
               FAR struct iob_s *next;
 
@@ -107,7 +113,7 @@ FAR struct iob_s *iob_trimhead(FAR struct iob_s *iob, unsigned int trimlen)
                */
 
               pktlen        -= iob->io_len;
-              len           -= iob->io_len;
+              trimlen       -= iob->io_len;
               iob->io_len    = 0;
               iob->io_offset = 0;
 
@@ -126,8 +132,9 @@ FAR struct iob_s *iob_trimhead(FAR struct iob_s *iob, unsigned int trimlen)
 
               /* Free this entry and set the next I/O buffer as the head */
 
+              nllvdbg("iob=%p: Freeing\n", iob);
               (void)iob_free(iob);
-              iob   = next;
+              iob = next;
             }
           else
             {
@@ -135,10 +142,10 @@ FAR struct iob_s *iob_trimhead(FAR struct iob_s *iob, unsigned int trimlen)
                * stop the trim.
                */
 
-              pktlen         -= len;
+              pktlen         -= trimlen;
-              iob->io_len    -= len;
+              iob->io_len    -= trimlen;
-              iob->io_offset += len;
+              iob->io_offset += trimlen;
-              len             = 0;
+              trimlen         = 0;
             }
         }
 

net/iob/iob_trimtail.c

@@ -39,6 +39,13 @@
 
 #include <nuttx/config.h>
 
+#if defined(CONFIG_DEBUG) && defined(CONFIG_NET_IOB_DEBUG)
+/* Force debug output (from this file only) */
+
+#  undef  CONFIG_DEBUG_NET
+#  define CONFIG_DEBUG_NET 1
+#endif
+
 #include <string.h>
 #include <debug.h>
 

net/net_send_buffered.c

@@ -548,18 +548,21 @@ static uint16_t send_interrupt(FAR struct uip_driver_s *dev, FAR void *pvconn,
               conn->sent    += sndlen;
             }
 
-          nllvdbg("SEND: nrtx=%d unacked=%d sent=%d\n",
+          nllvdbg("SEND: wrb=%p nrtx=%d unacked=%d sent=%d\n",
-                  WRB_NRTX(wrb), conn->unacked, conn->sent);
+                  wrb, WRB_NRTX(wrb), conn->unacked, conn->sent);
 
           /* Increment the count of bytes sent from this write buffer */
 
           WRB_SENT(wrb) += sndlen;
-          DEBUGASSERT(WRB_SENT(wrb) <= WRB_PKTLEN(wrb));
+
+          nllvdbg("SEND: wrb=%p sent=%d pktlen=%d\n",
+                  wrb, WRB_SENT(wrb), WRB_PKTLEN(wrb));
 
           /* Remove the write buffer from the write queue if the
            * last of the data has been sent from the buffer.
            */
 
+          DEBUGASSERT(WRB_SENT(wrb) <= WRB_PKTLEN(wrb));
           if (WRB_SENT(wrb) >= WRB_PKTLEN(wrb))
             {
               FAR struct tcp_wrbuffer_s *tmp;

net/net_sockets.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * net/net_sockets.c
  *
- *   Copyright (C) 2007-2009, 2011-2013 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011-2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -47,6 +47,7 @@
 #include <errno.h>
 #include <debug.h>
 
+#include <nuttx/net/iob.h>
 #include <nuttx/net/arp.h>
 #include <nuttx/net/uip/uip.h>
 #include <nuttx/net/net.h>

net/tcp/Kconfig

@@ -106,9 +106,10 @@ config NET_TCP_WRBUFFER_DEBUG
 	bool "Force write buffer debug"
 	default n
 	depends on DEBUG
+	select NET_IOB_DEBUG
 	---help---
 		This option will force debug output from TCP write buffer logic,
-		even with network debug output.  This is not normally something
+		even without network debug output.  This is not normally something
 		that would want to do but is convenient if you are debugging the
 		write buffer logic and do not want to get overloaded with other
 		network-related debug output.