From 50a3afd66fcc7b278e775ba3317e066471bf3e40 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Sun, 19 Sep 2021 15:15:37 +0100
Subject: [PATCH] Change to the new method of M17 EOT transmission.

---
 M17Control.cpp | 66 +++++++++++++++++---------------------------------
 M17Control.h   |  2 --
 M17Defines.h   |  1 +
 Modem.cpp      |  1 +
 Sync.cpp       |  7 ++++++
 Sync.h         |  1 +
 Version.h      |  2 +-
 7 files changed, 33 insertions(+), 47 deletions(-)

diff --git a/M17Control.cpp b/M17Control.cpp
index 50664a7..6834e94 100644
--- a/M17Control.cpp
+++ b/M17Control.cpp
@@ -329,8 +329,18 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 #if defined(DUMP_M17)
 		writeFile(data + 2U);
 #endif
-		if (m_duplex)
-			writeQueueEOTRF();
+		if (m_duplex) {
+			unsigned char rfData[M17_FRAME_LENGTH_BYTES + 2U];
+
+			rfData[0U] = TAG_EOT;
+			rfData[1U] = 0x00U;
+
+			// Generate the sync
+			for (unsigned int i = 0U; i < M17_FRAME_LENGTH_BYTES; i += M17_SYNC_LENGTH_BYTES)
+				CSync::addM17EOTSync(rfData + 2U + i);
+
+			writeQueueRF(rfData);
+		}
 
 		if (m_network != NULL && m_rfTimeoutTimer.isRunning() && !m_rfTimeoutTimer.hasExpired()) {
 			unsigned char netData[M17_LSF_LENGTH_BYTES + M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES];
@@ -560,7 +570,16 @@ void CM17Control::writeNetwork()
 
 			LogMessage("M17, received network end of transmission from %s to %s, %.1f seconds", source.c_str(), dest.c_str(), float(m_netFrames) / 25.0F);
 
-			writeQueueEOTNet();
+			unsigned char data[M17_FRAME_LENGTH_BYTES + 2U];
+
+			data[0U] = TAG_EOT;
+			data[1U] = 0x00U;
+
+			// Generate the sync
+			for (unsigned int i = 0U; i < M17_FRAME_LENGTH_BYTES; i += M17_SYNC_LENGTH_BYTES)
+				CSync::addM17EOTSync(data + 2U + i);
+
+			writeQueueNet(data);
 
 			writeEndNet();
 		}
@@ -686,28 +705,6 @@ void CM17Control::writeQueueRF(const unsigned char *data)
 	m_queue.addData(data, len);
 }
 
-void CM17Control::writeQueueEOTRF()
-{
-	if (m_netState != RS_NET_IDLE)
-		return;
-
-	if (m_rfTimeoutTimer.isRunning() && m_rfTimeoutTimer.hasExpired())
-		return;
-
-	const unsigned char len = 1U;
-
-	unsigned int space = m_queue.freeSpace();
-	if (space < (len + 1U)) {
-		LogError("M17, overflow in the M17 RF queue");
-		return;
-	}
-
-	m_queue.addData(&len, 1U);
-
-	const unsigned char data = TAG_EOT;
-	m_queue.addData(&data, len);
-}
-
 void CM17Control::writeQueueNet(const unsigned char *data)
 {
 	assert(data != NULL);
@@ -728,25 +725,6 @@ void CM17Control::writeQueueNet(const unsigned char *data)
 	m_queue.addData(data, len);
 }
 
-void CM17Control::writeQueueEOTNet()
-{
-	if (m_netTimeoutTimer.isRunning() && m_netTimeoutTimer.hasExpired())
-		return;
-
-	const unsigned char len = 1U;
-
-	unsigned int space = m_queue.freeSpace();
-	if (space < (len + 1U)) {
-		LogError("M17, overflow in the M17 RF queue");
-		return;
-	}
-
-	m_queue.addData(&len, 1U);
-
-	const unsigned char data = TAG_EOT;
-	m_queue.addData(&data, len);
-}
-
 void CM17Control::interleaver(const unsigned char* in, unsigned char* out) const
 {
 	assert(in != NULL);
diff --git a/M17Control.h b/M17Control.h
index f7cc775..ad9ef4c 100644
--- a/M17Control.h
+++ b/M17Control.h
@@ -82,10 +82,8 @@ private:
 	bool processRFHeader(bool lateEntry);
 
 	void writeQueueRF(const unsigned char* data);
-	void writeQueueEOTRF();
 
 	void writeQueueNet(const unsigned char* data);
-	void writeQueueEOTNet();
 
 	void writeNetwork();
 
diff --git a/M17Defines.h b/M17Defines.h
index ab69859..35fdc6b 100644
--- a/M17Defines.h
+++ b/M17Defines.h
@@ -26,6 +26,7 @@ const unsigned int M17_FRAME_LENGTH_BYTES   = M17_FRAME_LENGTH_BITS / 8U;
 
 const unsigned char M17_LINK_SETUP_SYNC_BYTES[] = {0x55U, 0xF7U};
 const unsigned char M17_STREAM_SYNC_BYTES[]     = {0xFFU, 0x5DU};
+const unsigned char M17_EOT_SYNC_BYTES[]        = {0x55U, 0x5DU};
 
 const unsigned int  M17_SYNC_LENGTH_BITS  = 16U;
 const unsigned int  M17_SYNC_LENGTH_BYTES = M17_SYNC_LENGTH_BITS / 8U;
diff --git a/Modem.cpp b/Modem.cpp
index 4b1b535..348d690 100644
--- a/Modem.cpp
+++ b/Modem.cpp
@@ -1534,6 +1534,7 @@ bool CModem::writeM17Data(const unsigned char* data, unsigned int length)
 			break;
 		case TAG_EOT:
 			buffer[2U] = MMDVM_M17_EOT;
+			::memcpy(buffer + 3U, data + 1U, length - 1U);
 			break;
 		default:
 			return false;
diff --git a/Sync.cpp b/Sync.cpp
index 6d38bbd..1fcb2c4 100644
--- a/Sync.cpp
+++ b/Sync.cpp
@@ -99,3 +99,10 @@ void CSync::addM17StreamSync(unsigned char* data)
 	::memcpy(data, M17_STREAM_SYNC_BYTES, M17_SYNC_LENGTH_BYTES);
 }
 
+void CSync::addM17EOTSync(unsigned char* data)
+{
+	assert(data != NULL);
+
+	::memcpy(data, M17_EOT_SYNC_BYTES, M17_SYNC_LENGTH_BYTES);
+}
+
diff --git a/Sync.h b/Sync.h
index 6190ae1..7f75711 100644
--- a/Sync.h
+++ b/Sync.h
@@ -35,6 +35,7 @@ public:
 
 	static void addM17LinkSetupSync(unsigned char* data);
 	static void addM17StreamSync(unsigned char* data);
+	static void addM17EOTSync(unsigned char* data);
 
 private:
 };
diff --git a/Version.h b/Version.h
index 44c1823..aba5baa 100644
--- a/Version.h
+++ b/Version.h
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210906";
+const char* VERSION = "20210919";
 
 #endif