Added a function to clear only the header part of the packetbuf

core/net/rime/packetbuf.c

@@ -33,7 +33,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * $Id: packetbuf.c,v 1.4 2009/10/20 08:06:43 adamdunkels Exp $
+ * $Id: packetbuf.c,v 1.5 2010/02/06 07:48:52 adamdunkels Exp $
  */
 
 /**
@@ -120,6 +120,12 @@ packetbuf_clear(void)
   packetbuf_attr_clear();
 }
 /*---------------------------------------------------------------------------*/
+void
+packetbuf_clear_hdr(void)
+{
+  hdrptr = PACKETBUF_HDR_SIZE;
+}
+/*---------------------------------------------------------------------------*/
 int
 packetbuf_copyfrom(const void *from, uint16_t len)
 {

core/net/rime/packetbuf.h

@@ -40,7 +40,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * $Id: packetbuf.h,v 1.4 2009/11/02 11:58:56 adamdunkels Exp $
+ * $Id: packetbuf.h,v 1.5 2010/02/06 07:48:52 adamdunkels Exp $
  */
 
 /**
@@ -85,6 +85,19 @@
  */
 void packetbuf_clear(void);
 
+/**
+ * \brief      Clear and reset the header of the packetbuf
+ *
+ *             This function clears the header of the packetbuf and
+ *             resets all the internal state pointers pertaining to
+ *             the header (header size, header pointer, but not
+ *             external data pointer). It is used before after sending
+ *             a packet in the packetbuf, to be able to reuse the
+ *             packet buffer for a later retransmission.
+ *
+ */
+void packetbuf_clear_hdr(void);
+
 /**
  * \brief      Get a pointer to the data in the packetbuf
  * \return     Pointer to the packetbuf data