DataFlash: handle knowledge of in_log_download in DataFlash

libraries/DataFlash/DataFlash.cpp

@@ -312,6 +312,9 @@ bool DataFlash_Class::should_log() const
     if (!vehicle_is_armed() && !log_while_disarmed()) {
         return false;
     }
+    if (in_log_download()) {
+        return false;
+    }
     if (_next_backend == 0) {
         return false;
     }

libraries/DataFlash/DataFlash.h

@@ -213,6 +213,7 @@ public:
     bool vehicle_is_armed() const { return _armed; }
 
     void handle_log_send(class GCS_MAVLINK &);
+    bool in_log_download() const { return _in_log_download; }
 
 protected:
 
@@ -294,6 +295,9 @@ private:
     uint8_t  _log_listing:1; // sending log list
     uint8_t  _log_sending:1; // sending log data
 
+    // bolean replicating old vehicle in_log_download flag:
+    bool _in_log_download:1;
+
     // next log list entry to send
     uint16_t _log_next_list_entry;
 
@@ -318,6 +322,7 @@ private:
     // start page of log data
     uint16_t _log_data_page;
 
+    bool should_handle_log_message();
     void handle_log_message(class GCS_MAVLINK &, mavlink_message_t *msg);
 
     void handle_log_request_list(class GCS_MAVLINK &, mavlink_message_t *msg);

libraries/DataFlash/DataFlash_MAVLinkLogTransfer.cpp

@@ -24,11 +24,27 @@
 
 extern const AP_HAL::HAL& hal;
 
+// We avoid doing log messages when timing is critical:
+bool DataFlash_Class::should_handle_log_message()
+{
+    if (!WritesEnabled()) {
+        // this is currently used as a proxy for "in_mavlink_delay"
+        return false;
+    }
+    if (vehicle_is_armed()) {
+        return false;
+    }
+    return true;
+}
+
 /**
    handle all types of log download requests from the GCS
  */
 void DataFlash_Class::handle_log_message(GCS_MAVLINK &link, mavlink_message_t *msg)
 {
+    if (!should_handle_log_message()) {
+        return;
+    }
     switch (msg->msgid) {
     case MAVLINK_MSG_ID_LOG_REQUEST_LIST:
         handle_log_request_list(link, msg);
@@ -85,6 +101,8 @@ void DataFlash_Class::handle_log_request_data(GCS_MAVLINK &link, mavlink_message
     mavlink_log_request_data_t packet;
     mavlink_msg_log_request_data_decode(msg, &packet);
 
+    _in_log_download = true;
+
     _log_listing = false;
     if (!_log_sending || _log_num_data != packet.id) {
         _log_sending = false;
@@ -135,6 +153,7 @@ void DataFlash_Class::handle_log_request_end(GCS_MAVLINK &link, mavlink_message_
 {
     mavlink_log_request_end_t packet;
     mavlink_msg_log_request_end_decode(msg, &packet);
+    _in_log_download = false;
     _log_sending = false;
 }