edge: Add bitvec based DL window updating methods

The current methods are based on the GRPS specific RBB and SSN values
and formats which are not compatible with EGPRS.

Add a second set of similar methods with the same semantics but
which are based on a bitvec and the first BSN instead.

The following methods are affected:

- gprs_rlc_dl_window::update
- gprs_rlcmac_dl_tbf::rcvd_dl_ack
- gprs_rlcmac_dl_tbf::update_window

Sponsored-by: On-Waves ehf

1 files changed, 31 insertions, 0 deletions

diff --git a/src/rlc.cpp b/src/rlc.cpp
index 1a8efdf6..6d3cfd59 100644
--- a/src/rlc.cpp
+++ b/src/rlc.cpp
@@ -114,6 +114,37 @@ static uint16_t bitnum_to_bsn(int bitnum, uint16_t ssn)
 	return (ssn - 1 - bitnum);
 }
 
+void gprs_rlc_dl_window::update(BTS *bts, const struct bitvec *rbb,
+			uint16_t first_bsn, uint16_t *lost,
+			uint16_t *received)
+{
+	unsigned num_blocks = rbb->cur_bit;
+	unsigned bsn;
+
+	/* first_bsn is in range V(A)..V(S) */
+
+	for (unsigned int bitpos = 0; bitpos < num_blocks; bitpos++) {
+		bool is_ack;
+		bsn = mod_sns(first_bsn + bitpos);
+		if (bsn == mod_sns(v_a() - 1))
+			break;
+
+		is_ack = bitvec_get_bit_pos(rbb, bitpos) == 1;
+
+		if (is_ack) {
+			LOGP(DRLCMACDL, LOGL_DEBUG, "- got ack for BSN=%d\n", bsn);
+			if (!m_v_b.is_acked(bsn))
+				*received += 1;
+			m_v_b.mark_acked(bsn);
+		} else {
+			LOGP(DRLCMACDL, LOGL_DEBUG, "- got NACK for BSN=%d\n", bsn);
+			m_v_b.mark_nacked(bsn);
+			bts->rlc_nacked();
+			*lost += 1;
+		}
+	}
+}
+
 void gprs_rlc_dl_window::update(BTS *bts, char *show_rbb, uint16_t ssn,
 			uint16_t *lost, uint16_t *received)
 {