From 27a454ef722d4bc81f301e51dd9f9f4fdf02480e Mon Sep 17 00:00:00 2001
From: gardners <paul@servalproject.org>
Date: Mon, 5 Sep 2011 12:49:37 +0930
Subject: [PATCH] Initial implementation of frame enqueuing.  Queues require
 maxLength to be initalised to set congestion threshold.

---
 mphlr.h           |  6 ++++--
 overlay.c         |  6 ++++--
 overlay_payload.c | 20 +++++++++++++++++++-
 3 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/mphlr.h b/mphlr.h
index df8ad419..35debafe 100644
--- a/mphlr.h
+++ b/mphlr.h
@@ -550,8 +550,9 @@ int ob_unlimitsize(overlay_buffer *b);
 typedef struct overlay_txqueue {
   struct overlay_frame *first;
   struct overlay_frame *last;
-  int length;
-  int maxLength;
+  int length; /* # frames in queue */
+  int maxLength; /* max # frames in queue before we consider ourselves congested */
+
   /* Latency target in ms for this traffic class.
      Frames older than the latency target will get dropped. */
   int latencyTarget;
@@ -776,4 +777,5 @@ int overlay_frame_set_me_as_source(overlay_frame *f);
 int overlay_update_sequence_number();
 int packetEncipher(unsigned char *packet,int maxlen,int *len,int cryptoflags);
 int overlayServerMode();
+int overlay_payload_enqueue(int q,overlay_frame *p);
 
diff --git a/overlay.c b/overlay.c
index 2d108580..3867e489 100644
--- a/overlay.c
+++ b/overlay.c
@@ -209,8 +209,10 @@ int overlay_frame_process(int interface,overlay_frame *f)
 	if (overlay_get_nexthop(f->destination,f->nexthop,&len))
 	  return WHY("Could not find next hop for host - dropping frame");
 	f->ttl--;
-
-	/* Queue frame for dispatch */		
+	
+	/* Queue frame for dispatch.
+	   Don't forget to put packet in the correct queue based on type.
+	   (e.g., mesh management, voice, video, ordinary or opportunistic). */		
 	WHY("forwarding of frames not implemented");
 	
 	/* If the frame was a broadcast frame, then we need to hang around
diff --git a/overlay_payload.c b/overlay_payload.c
index 90711a34..c4e8644d 100644
--- a/overlay_payload.c
+++ b/overlay_payload.c
@@ -136,9 +136,27 @@ overlay_buffer *overlay_payload_unpackage(overlay_frame *b) {
 int overlay_payload_enqueue(int q,overlay_frame *p)
 {
   /* Add payload p to queue q.
+
+     Queues get scanned from first to last, so we should append new entries
+     on the end of the queue.
+
+     Complain if there are too many frames in the queue.
   */
 
-  return WHY("not implemented");
+  if (q<0||q>=OQ_MAX) return WHY("Invalid queue specified");
+  if (!p) return WHY("Cannot queue NULL");
+
+  if (overlay_tx[q].length>=overlay_tx[q].maxLength) return WHY("Queue congested");
+  
+  overlay_frame *l=overlay_tx[q].last;
+  if (l) l->next=p;
+  p->prev=l;
+  p->next=NULL;
+  overlay_tx[q].last=p;
+  if (!overlay_tx[q].first) overlay_tx[q].first=p;
+  overlay_tx[q].length++;
+  
+  return 0;
 }
 
 int op_free(overlay_frame *p)