From 2019718b3f84daee751018de7b0593815e81d5b5 Mon Sep 17 00:00:00 2001
From: Manolis Surligas <surligas@gmail.com>
Date: Thu, 19 Sep 2019 21:09:22 +0300
Subject: [PATCH] Support frame tagging on the IEEE 802.15.4 decoder

---
 include/satnogs/ieee802_15_4_variant_decoder.h | 1 +
 lib/ax25_decoder.cc                            | 4 ++--
 lib/ieee802_15_4_variant_decoder.cc            | 9 ++++++++-
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/include/satnogs/ieee802_15_4_variant_decoder.h b/include/satnogs/ieee802_15_4_variant_decoder.h
index 48b9aa0..ddb9a39 100644
--- a/include/satnogs/ieee802_15_4_variant_decoder.h
+++ b/include/satnogs/ieee802_15_4_variant_decoder.h
@@ -126,6 +126,7 @@ private:
   size_t                        d_length_field_len;
   decoding_state_t              d_state;
   size_t                        d_cnt;
+  uint64_t                      d_frame_start_idx;
   uint8_t                       *d_pdu;
 
   decoder_status_t
diff --git a/lib/ax25_decoder.cc b/lib/ax25_decoder.cc
index de76564..a1e993a 100644
--- a/lib/ax25_decoder.cc
+++ b/lib/ax25_decoder.cc
@@ -112,7 +112,7 @@ ax25_decoder::_decode(decoder_status_t &status)
           d_bitstream.erase(d_bitstream.begin(),
                             d_bitstream.begin() + i + 1);
           /* Increment the number of items read so far */
-          incr_nitems_read(i);
+          incr_nitems_read(i + 1);
           enter_sync_state();
           /* Mark possible start of the frame */
           d_frame_start = nitems_read();
@@ -162,7 +162,7 @@ ax25_decoder::_decode(decoder_status_t &status)
             d_bitstream.erase(d_bitstream.begin(),
                               d_bitstream.begin() + i + 1);
             /* Increment the number of items read so far */
-            incr_nitems_read(i);
+            incr_nitems_read(i + 1);
             d_start_idx = d_bitstream.size();
             return true;
           }
diff --git a/lib/ieee802_15_4_variant_decoder.cc b/lib/ieee802_15_4_variant_decoder.cc
index 4e0d014..29796c2 100644
--- a/lib/ieee802_15_4_variant_decoder.cc
+++ b/lib/ieee802_15_4_variant_decoder.cc
@@ -73,6 +73,7 @@ ieee802_15_4_variant_decoder::ieee802_15_4_variant_decoder(
   d_length_field_len(0),
   d_state(SEARCHING),
   d_cnt(0),
+  d_frame_start_idx(0),
   d_pdu(new uint8_t[max_len])
 {
   for (uint8_t b : preamble) {
@@ -173,6 +174,7 @@ ieee802_15_4_variant_decoder::decode_var_len(const void *in, int len)
   default:
     throw std::runtime_error("ieee802_15_4_variant_decoder: Invalid state");
   }
+  incr_nitems_read(static_cast<uint64_t>(status.consumed));
   return status;
 }
 
@@ -193,6 +195,7 @@ ieee802_15_4_variant_decoder::decode_const_len(const void *in, int len)
   default:
     throw std::runtime_error("ieee802_15_4_variant_decoder: Invalid state");
   }
+  incr_nitems_read(static_cast<uint64_t>(status.consumed));
   return status;
 }
 
@@ -215,6 +218,7 @@ ieee802_15_4_variant_decoder::search_preamble(const uint8_t *in, int len)
     shift_reg tmp = d_preamble_shift_reg ^ d_preamble;
     if (tmp.count() <= d_preamble_thrsh) {
       d_state = SEARCHING_SYNC;
+      d_frame_start_idx = nitems_read() + i + 1;
       d_cnt = 0;
       return i + 1;
     }
@@ -304,8 +308,11 @@ ieee802_15_4_variant_decoder::decode_payload(decoder_status_t &status,
 
       status.decode_success = true;
       status.consumed = (i + 1) * 8;
+      metadata::add_time_iso8601(status.data);
+      metadata::add_sample_start(status.data, d_frame_start_idx);
+      metadata::add_sample_cnt(status.data,
+                               nitems_read() + (i + 1) * 8 - d_frame_start_idx);
       if (check_crc()) {
-        metadata::add_time_iso8601(status.data);
         metadata::add_pdu(status.data, d_pdu + d_length_field_len,
                           d_len - crc::crc_size(d_crc));
         metadata::add_crc_valid(status.data, true);