From 78c8ed3e9753df51ecbb6bed4a8fdddca1428ee0 Mon Sep 17 00:00:00 2001
From: Verkehrsrot <cyberman@obh.snafu.de>
Date: Wed, 28 Aug 2019 21:55:50 +0200
Subject: [PATCH] refactoring LMIC send queueing

---
 src/lorawan.cpp  | 47 ++++++++++++++++++++++++++++-------------------
 src/senddata.cpp |  2 +-
 2 files changed, 29 insertions(+), 20 deletions(-)

diff --git a/src/lorawan.cpp b/src/lorawan.cpp
index 3974c7f4..fefb5db0 100644
--- a/src/lorawan.cpp
+++ b/src/lorawan.cpp
@@ -248,6 +248,11 @@ void onEvent(ev_t ev) {
                                                : PSTR("TX COMPLETE"));
     sprintf(display_line6, " "); // clear previous lmic status
 
+    // schedule next transmission with some random delay to prevent systematic
+    // collisions
+    os_setTimedCallback(&sendjob, os_getTime() + ms2osticks(random(500)),
+                        lora_send);
+
     if (LMIC.dataLen) { // did we receive payload data -> display info
       ESP_LOGI(TAG, "Received %d bytes of payload, RSSI %d SNR %d",
                LMIC.dataLen, LMIC.rssi, LMIC.snr / 4);
@@ -391,22 +396,22 @@ void switch_lora(uint8_t sf, uint8_t tx) {
 
 void lora_send(osjob_t *job) {
   MessageBuffer_t SendBuffer;
-  if (xQueueReceive(LoraSendQueue, &SendBuffer, (TickType_t)0) == pdTRUE) {
-    // SendBuffer now filled with next payload from queue
-    if (LMIC_setTxData2(SendBuffer.MessagePort, SendBuffer.Message,
-                        SendBuffer.MessageSize,
-                        (cfg.countermode & 0x02)) == 0) {
-      ESP_LOGI(TAG, "%d byte(s) sent to LoRa", SendBuffer.MessageSize);
-    } else {
-      lora_enqueuedata(&SendBuffer);
-      // ESP_LOGE(TAG, "could not send %d byte(s) to LoRa, rescheduled",
-      //         SendBuffer.MessageSize);
-    }
+
+  // Check if there is not a current TX/RX job running
+  if (LMIC.opmode & OP_TXRXPEND) {
+    ESP_LOGE(TAG, "LMIC busy, data not sent and lost");
+    return;
+  }
+
+  // fetch next payload to send from queue or wait until new payload shows up in
+  // queue
+  if (xQueueReceive(LoraSendQueue, &SendBuffer, portMAX_DELAY) == pdTRUE) {
+    if (LMIC_setTxData2(SendBuffer.MessagePort, SendBuffer.Message,
+                        SendBuffer.MessageSize, (cfg.countermode & 0x02)) == 0)
+      ESP_LOGI(TAG, "%d byte(s) delivered to LMIC", SendBuffer.MessageSize);
+    else
+      lora_enqueuedata(&SendBuffer); // re-enqueue unsent message
   }
-  // reschedule job every 0,5 - 1 sec. including a bit of random to prevent
-  // systematic collisions
-  os_setTimedCallback(job, os_getTime() + 500 + ms2osticks(random(500)),
-                      lora_send);
 }
 
 esp_err_t lora_stack_init() {
@@ -438,15 +443,17 @@ esp_err_t lora_stack_init() {
 
 void lora_enqueuedata(MessageBuffer_t *message) {
   // enqueue message in LORA send queue
-  BaseType_t ret;
+  BaseType_t ret = pdFALSE;
   MessageBuffer_t DummyBuffer;
   sendprio_t prio = message->MessagePrio;
 
   switch (prio) {
   case prio_high:
-    // clear space in queue if full, then fallthrough to normal
-    if (uxQueueSpacesAvailable(LoraSendQueue) == 0)
+    // clear some space in queue if full, then fallthrough to prio_normal
+    if (uxQueueSpacesAvailable(LoraSendQueue) == 0) {
       xQueueReceive(LoraSendQueue, &DummyBuffer, (TickType_t)0);
+      ESP_LOGW(TAG, "LORA sendqueue purged, data is lost");
+    }
   case prio_normal:
     ret = xQueueSendToFront(LoraSendQueue, (void *)message, (TickType_t)0);
     break;
@@ -455,7 +462,9 @@ void lora_enqueuedata(MessageBuffer_t *message) {
     ret = xQueueSendToBack(LoraSendQueue, (void *)message, (TickType_t)0);
     break;
   }
-  if (ret != pdTRUE)
+  if (ret == pdTRUE)
+    ESP_LOGD(TAG, "LORA sendqueue data enqueued");
+  else
     ESP_LOGW(TAG, "LORA sendqueue is full");
 }
 
diff --git a/src/senddata.cpp b/src/senddata.cpp
index 95577b24..65d656c5 100644
--- a/src/senddata.cpp
+++ b/src/senddata.cpp
@@ -40,7 +40,7 @@ void SendPayload(uint8_t port, sendprio_t prio) {
   default:
     SendBuffer.MessagePort = port;
   }
-  memcpy(SendBuffer.Message, payload.getBuffer(), payload.getSize());
+  memcpy(SendBuffer.Message, payload.getBuffer(), SendBuffer.MessageSize);
 
 // enqueue message in device's send queues
 #if (HAS_LORA)