From bc9934ee5a9cc511a10c9e383dd86229c58d0de0 Mon Sep 17 00:00:00 2001
From: Simon Duquennoy <simon.duquennoy@ri.se>
Date: Fri, 18 May 2018 05:52:09 -0700
Subject: [PATCH] Implement function uip_sr_link_snprint

---
 os/net/ipv6/uip-sr.c | 46 ++++++++++++++++++++++++++++++++++++++++++++
 os/net/ipv6/uip-sr.h | 11 +++++++++++
 2 files changed, 57 insertions(+)

diff --git a/os/net/ipv6/uip-sr.c b/os/net/ipv6/uip-sr.c
index 15b123552..a82491827 100644
--- a/os/net/ipv6/uip-sr.c
+++ b/os/net/ipv6/uip-sr.c
@@ -41,6 +41,7 @@
 
 #include "contiki.h"
 #include "net/ipv6/uip-sr.h"
+#include "net/ipv6/uiplib.h"
 #include "net/routing/routing.h"
 #include "lib/list.h"
 #include "lib/memb.h"
@@ -246,4 +247,49 @@ uip_sr_free_all(void)
     num_nodes--;
   }
 }
+/*---------------------------------------------------------------------------*/
+int
+uip_sr_link_snprint(char *buf, int buflen, uip_sr_node_t *link)
+{
+  int index = 0;
+  uip_ipaddr_t child_ipaddr;
+  uip_ipaddr_t parent_ipaddr;
+
+  NETSTACK_ROUTING.get_sr_node_ipaddr(&child_ipaddr, link);
+  NETSTACK_ROUTING.get_sr_node_ipaddr(&parent_ipaddr, link->parent);
+
+  index += uiplib_ipaddr_snprint(buf+index, buflen-index, &child_ipaddr);
+  if(index >= buflen) {
+    return index;
+  }
+
+  if(link->parent == NULL) {
+    index += snprintf(buf+index, buflen-index, "  (DODAG root)");
+    if(index >= buflen) {
+      return index;
+    }
+  } else {
+    index += snprintf(buf+index, buflen-index, "  to ");
+    if(index >= buflen) {
+      return index;
+    }
+    index += uiplib_ipaddr_snprint(buf+index, buflen-index, &parent_ipaddr);
+    if(index >= buflen) {
+      return index;
+    }
+  }
+  if(link->lifetime != UIP_SR_INFINITE_LIFETIME) {
+    index += snprintf(buf+index, buflen-index,
+              " (lifetime: %lu seconds)", (unsigned long)link->lifetime);
+    if(index >= buflen) {
+      return index;
+    }
+  } else {
+    index += snprintf(buf+index, buflen-index, " (lifetime: infinite)");
+    if(index >= buflen) {
+      return index;
+    }
+  }
+  return index;
+}
 /** @} */
diff --git a/os/net/ipv6/uip-sr.h b/os/net/ipv6/uip-sr.h
index 7224cea14..01ed57c1c 100644
--- a/os/net/ipv6/uip-sr.h
+++ b/os/net/ipv6/uip-sr.h
@@ -180,6 +180,17 @@ void uip_sr_init(void);
 */
 void uip_sr_free_all(void);
 
+/**
+* Print a textual description of a source routing link
+*
+* \param buf The buffer where to write content
+* \param buflen The buffer len
+* \param link A pointer to the source routing link
+* \return Identical to snprintf: number of bytes written excluding ending null
+* byte. A value >= buflen if the buffer was too small.
+*/
+int uip_sr_link_snprint(char *buf, int buflen, uip_sr_node_t *link);
+
  /** @} */
 
 #endif /* UIP_SR_H */