Merge pull request #2007 from mavlink/pr-v1.4-wait-for-info

[BACKPORT v1.4] info: wait up to 1.5s for information

Author: julianoes

src/mavsdk/plugins/info/info_impl.cpp

@@ -191,6 +191,8 @@ std::string InfoImpl::translate_binary_to_str(uint8_t* binary, unsigned binary_l
 
 std::pair<Info::Result, Info::Identification> InfoImpl::get_identification() const
 {
+    wait_for_information();
+
     std::lock_guard<std::mutex> lock(_mutex);
     return std::make_pair<>(
         (_information_received ? Info::Result::Success : Info::Result::InformationNotReceivedYet),
@@ -199,23 +201,30 @@ std::pair<Info::Result, Info::Identification> InfoImpl::get_identification() con
 
 std::pair<Info::Result, Info::Version> InfoImpl::get_version() const
 {
+    wait_for_information();
+
     std::lock_guard<std::mutex> lock(_mutex);
+
     return std::make_pair<>(
         (_information_received ? Info::Result::Success : Info::Result::InformationNotReceivedYet),
         _version);
 }
 
 std::pair<Info::Result, Info::Product> InfoImpl::get_product() const
 {
+    wait_for_information();
     std::lock_guard<std::mutex> lock(_mutex);
+
     return std::make_pair<>(
         (_information_received ? Info::Result::Success : Info::Result::InformationNotReceivedYet),
         _product);
 }
 
 std::pair<Info::Result, Info::FlightInfo> InfoImpl::get_flight_information() const
 {
+    wait_for_information();
     std::lock_guard<std::mutex> lock(_mutex);
+
     return std::make_pair<>(
         (_flight_information_received ? Info::Result::Success :
                                         Info::Result::InformationNotReceivedYet),
@@ -281,4 +290,15 @@ std::pair<Info::Result, double> InfoImpl::get_speed_factor() const
     return std::make_pair<>(Info::Result::Success, speed_factor);
 }
 
+void InfoImpl::wait_for_information() const
+{
+    // Wait 1.5 seconds max
+    for (unsigned i = 0; i < 150; ++i) {
+        if (_information_received) {
+            break;
+        }
+        std::this_thread::sleep_for(std::chrono::milliseconds(10));
+    }
+}
+
 } // namespace mavsdk

src/mavsdk/plugins/info/info_impl.h

@@ -38,13 +38,15 @@ class InfoImpl : public PluginImplBase {
     void process_flight_information(const mavlink_message_t& message);
     void process_attitude(const mavlink_message_t& message);
 
+    void wait_for_information() const;
+
     mutable std::mutex _mutex{};
 
     Info::Version _version{};
     Info::Product _product{};
     Info::Identification _identification{};
     Info::FlightInfo _flight_info{};
-    bool _information_received{false};
+    std::atomic<bool> _information_received{false};
     bool _flight_information_received{false};
     bool _was_armed{false};