From 941443878b2650eefdf5a7ed3a18cd0163fea77d Mon Sep 17 00:00:00 2001
From: joxe <joxe>
Date: Wed, 2 Jun 2010 16:23:08 +0000
Subject: [PATCH] fixed rank calculation bug in of-etx

---
 core/net/rpl/rpl-dag.c    |  6 +++---
 core/net/rpl/rpl-of-etx.c | 22 +++++++++++++---------
 core/net/rpl/rpl.h        |  9 +++++++--
 3 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/core/net/rpl/rpl-dag.c b/core/net/rpl/rpl-dag.c
index 19ae1b69c..bacd5a799 100644
--- a/core/net/rpl/rpl-dag.c
+++ b/core/net/rpl/rpl-dag.c
@@ -32,7 +32,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * $Id: rpl-dag.c,v 1.13 2010/06/02 11:59:51 joxe Exp $
+ * $Id: rpl-dag.c,v 1.14 2010/06/02 16:23:08 joxe Exp $
  */
 /**
  * \file
@@ -568,8 +568,8 @@ rpl_process_dio(uip_ipaddr_t *from, rpl_dio_t *dio)
 
   if(dio->dag_rank < dag->rank) {
     /* Message from a node closer to the root, but we might still be out of allowed rank-range */
-    if(dag->max_rankinc > 0 &&
-       dag->min_rank + dag->max_rankinc < dag->of->increment_rank(dio->dag_rank, p)) {
+    if(dag->max_rankinc > 0 && dag->min_rank + dag->max_rankinc <
+       dag->of->increment_rank(dio->dag_rank, NULL)) {
         PRINTF("RPL: Could not add parent, resulting rank too high\n");
         return;
     }
diff --git a/core/net/rpl/rpl-of-etx.c b/core/net/rpl/rpl-of-etx.c
index ec73933f1..d0bf78a75 100644
--- a/core/net/rpl/rpl-of-etx.c
+++ b/core/net/rpl/rpl-of-etx.c
@@ -32,7 +32,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * $Id: rpl-of-etx.c,v 1.2 2010/05/31 14:22:00 nvt-se Exp $
+ * $Id: rpl-of-etx.c,v 1.3 2010/06/02 16:23:11 joxe Exp $
  */
 /**
  * \file
@@ -64,9 +64,9 @@ rpl_of_t rpl_of_etx = {
 #define PATH_ETX_MIN			1
 #define PATH_ETX_MAX			200
 #define PARENT_SWITCH_ETX_THRESHOLD	0.5
-#define INFINITY			255
+#define INFINITY			0xffff
 
-typedef unsigned char etx_t;
+typedef unsigned int etx_t;
 
 static etx_t min_path_etx = INFINITY;
 
@@ -86,7 +86,8 @@ parent_state_callback(rpl_parent_t *parent, int known, int etx)
   if(known) {
     if(min_path_etx != INFINITY) {
       dag->rank = min_path_etx + etx;
-      PRINTF("RPL: New path ETX: %u\n", (unsigned)(min_path_etx + etx));
+      PRINTF("RPL: New path ETX: %u  min_path_etx=%u etx=%u\n",
+             (unsigned)(min_path_etx + etx), min_path_etx, etx);
     }
   } else {
     if(RPL_PARENT_COUNT(dag) == 1) {
@@ -103,15 +104,18 @@ increment_rank(rpl_rank_t rank, rpl_parent_t *parent)
 
   PRINTF("RPL: OF1 increment rank\n");
 
-  if(parent->rank < min_path_etx) {
+  if(parent != NULL && parent->rank < min_path_etx) {
     min_path_etx = parent->rank;
+    PRINTF("RPL: min_path_etx updated to:%u\n", min_path_etx);
   }
 
-  new_rank = parent->rank + LINK_ETX_MAX;
+  /* calculate the rank based on the new rank information from DIO or
+     stored otherwise */
+  new_rank = rank + LINK_ETX_MAX;
 
-  if(new_rank < rank) {
-    return INFINITE_RANK;
-  }
+  /* if(new_rank < rank) { */
+  /*   return INFINITE_RANK; */
+  /* } */
 
   PRINTF("RPL: Path ETX %u\n", (unsigned)new_rank);
 
diff --git a/core/net/rpl/rpl.h b/core/net/rpl/rpl.h
index cbbd5eda2..f8a797624 100644
--- a/core/net/rpl/rpl.h
+++ b/core/net/rpl/rpl.h
@@ -30,7 +30,7 @@
  *
  * Author: Joakim Eriksson, Nicolas Tsiftes
  *
- * $Id: rpl.h,v 1.8 2010/06/02 11:59:52 joxe Exp $
+ * $Id: rpl.h,v 1.9 2010/06/02 16:23:12 joxe Exp $
  */
 
 #ifndef RPL_H
@@ -165,7 +165,12 @@ struct rpl_of {
   void (*reset)(void *);
   void (*parent_state_callback)(rpl_parent_t *, int, int);
   rpl_parent_t *(*best_parent)(rpl_parent_t *, rpl_parent_t *);
-  rpl_rank_t (*increment_rank)(rpl_rank_t, rpl_parent_t *);
+
+  /* Increment the rank - the rank that just have been received in a DIO
+     (or if picked from a parent) is the first argument. This is considered
+     the valid rank to calculate based on. The second argument is the parent
+     that is related to this calculation - if any (can be NULL) */
+  rpl_rank_t (*increment_rank)(rpl_rank_t rank, rpl_parent_t *parent);
   rpl_ocp_t ocp;
 };