From 74780d59626492f7dcb1f04a1d08c23532e84d49 Mon Sep 17 00:00:00 2001
From: kkrentz <konrad.krentz@gmail.com>
Date: Mon, 30 Apr 2018 06:54:00 -0700
Subject: [PATCH] CSMA: Do not parse twice/Acknowledge MAC command frames, too

---
 os/net/mac/csma/csma.c            | 25 ++++++-------------------
 os/net/mac/framer/framer-802154.c |  1 +
 os/net/mac/framer/nullframer.c    |  1 +
 3 files changed, 8 insertions(+), 19 deletions(-)

diff --git a/os/net/mac/csma/csma.c b/os/net/mac/csma/csma.c
index 7259e35c8..17606916e 100644
--- a/os/net/mac/csma/csma.c
+++ b/os/net/mac/csma/csma.c
@@ -60,11 +60,7 @@ static void
 input_packet(void)
 {
 #if CSMA_SEND_SOFT_ACK
-  int original_datalen;
-  uint8_t *original_dataptr;
-
-  original_datalen = packetbuf_datalen();
-  original_dataptr = packetbuf_dataptr();
+  uint8_t ackdata[CSMA_ACK_LEN];
 #endif
 
   if(packetbuf_datalen() == CSMA_ACK_LEN) {
@@ -91,20 +87,11 @@ input_packet(void)
     }
 
 #if CSMA_SEND_SOFT_ACK
-    {
-      frame802154_t info154;
-      frame802154_parse(original_dataptr, original_datalen, &info154);
-      if(info154.fcf.frame_type == FRAME802154_DATAFRAME &&
-         info154.fcf.ack_required != 0 &&
-         linkaddr_cmp((linkaddr_t *)&info154.dest_addr,
-                      &linkaddr_node_addr)) {
-        uint8_t ackdata[CSMA_ACK_LEN] = {0, 0, 0};
-
-        ackdata[0] = FRAME802154_ACKFRAME;
-        ackdata[1] = 0;
-        ackdata[2] = info154.seq;
-        NETSTACK_RADIO.send(ackdata, CSMA_ACK_LEN);
-      }
+    if(packetbuf_attr(PACKETBUF_ATTR_MAC_ACK)) {
+      ackdata[0] = FRAME802154_ACKFRAME;
+      ackdata[1] = 0;
+      ackdata[2] = ((uint8_t *)packetbuf_hdrptr())[2];
+      NETSTACK_RADIO.send(ackdata, CSMA_ACK_LEN);
     }
 #endif /* CSMA_SEND_SOFT_ACK */
     if(!duplicate) {
diff --git a/os/net/mac/framer/framer-802154.c b/os/net/mac/framer/framer-802154.c
index b4c24da19..8e92b9b2d 100644
--- a/os/net/mac/framer/framer-802154.c
+++ b/os/net/mac/framer/framer-802154.c
@@ -240,6 +240,7 @@ parse(void)
 
   if(hdr_len && packetbuf_hdrreduce(hdr_len)) {
     packetbuf_set_attr(PACKETBUF_ATTR_FRAME_TYPE, frame.fcf.frame_type);
+    packetbuf_set_attr(PACKETBUF_ATTR_MAC_ACK, frame.fcf.ack_required);
 
     if(frame.fcf.dest_addr_mode) {
       if(frame.dest_pid != frame802154_get_pan_id() &&
diff --git a/os/net/mac/framer/nullframer.c b/os/net/mac/framer/nullframer.c
index 019ed2209..ae7bc925d 100644
--- a/os/net/mac/framer/nullframer.c
+++ b/os/net/mac/framer/nullframer.c
@@ -87,6 +87,7 @@ parse(void)
     }
     packetbuf_set_addr(PACKETBUF_ADDR_SENDER, (linkaddr_t *)&frame.src_addr);
     packetbuf_set_attr(PACKETBUF_ATTR_MAC_SEQNO, frame.seq);
+    packetbuf_set_attr(PACKETBUF_ATTR_MAC_ACK, frame.fcf.ack_required);
     return 0;
   }
 #endif