read-api: Addressed comments from review

examples/ulog_data.cpp

@@ -45,52 +45,69 @@ int main(int argc, char** argv)
   // Read out some data
 
   // List all subscription names
-  for (const auto& sub : data_container->subscriptionNames()) {
+  auto subscription_names = data_container->subscriptionNames();
+  for (const auto& sub : subscription_names) {
     std::cout << sub << "\n";
   }
 
   // Get a particular subscription
-  const auto& subscription = data_container->subscription("vehicle_status");
+  if (subscription_names.find("vehicle_status") != subscription_names.end()) {
+    const auto& subscription = data_container->subscription("vehicle_status");
 
-  // Get message format of subscription
-  auto message_format = subscription->format();
-  std::cout << "Message format: " << message_format->name() << "\n";
+    // Get message format of subscription
+    auto message_format = subscription->format();
+    std::cout << "Message format: " << message_format->name() << "\n";
 
-  // List all field names
-  for (const std::string& field : subscription->fieldNames()) {
-    std::cout << field << "\n";
-  }
+    // List all field names
+    std::cout << "Field names: "
+              << "\n";
+    for (const std::string& field : subscription->fieldNames()) {
+      std::cout << field << "\n";
+    }
 
-  // Get particular field
-  auto nav_state_field = subscription->field("nav_state");
+    // Get particular field
+    auto nav_state_field = subscription->field("nav_state");
 
-  // Iterate over all samples
-  for (const auto& sample : *subscription) {
-    // always correctly extracts the type as defined in the message definition,
-    // gets cast to the value you put in int.
-    // This also works for arrays and strings.
-    auto nav_state = sample[nav_state_field].as<int>();
-    std::cout << nav_state << "\n";
-  }
+    // Iterate over all samples
+    std::cout << "nav_state values: \n";
+    for (const auto& sample : *subscription) {
+      // always correctly extracts the type as defined in the message definition,
+      // gets cast to the value you put in int.
+      // This also works for arrays and strings.
+      auto nav_state = sample[nav_state_field].as<int>();
+      std::cout << nav_state << ", ";
+    }
+    std::cout << "\n";
 
-  // get a specific sample
-  auto sample_12 = subscription->at(12);
+    // get a specific sample
+    auto sample_12 = subscription->at(12);
 
-  // access values by name
-  auto timestamp = sample_12["timestamp"].as<uint64_t>();
+    // access values by name
+    auto timestamp = sample_12["timestamp"].as<uint64_t>();
 
-  std::cout << timestamp << "\n";
+    std::cout << timestamp << "\n";
+  } else {
+    std::cout << "No vehicle_status subscription found\n";
+  }
 
-  // get from nested data type
-  auto esc_format =
-      data_container->messageFormats().at("esc_status")->field("esc")->type().nested_message;
-  for (const auto& field_name : esc_format->fieldNames()) {
-    std::cout << field_name << "\n";
+  if (data_container->messageFormats().find("esc_status") !=
+      data_container->messageFormats().end()) {
+    const auto& message_format = data_container->messageFormats().at("esc_status");
+    std::cout << "Message format: " << message_format->name() << "\n";
+    for (const auto& field_name : message_format->fieldNames()) {
+      std::cout << field_name << "\n";
+    }
+  } else {
+    std::cout << "No esc_status message format found\n";
   }
 
-  auto esc_status = data_container->subscription("esc_status");
-  for (const auto& sample : *esc_status) {
-    std::cout << "timestamp: " << sample["esc"][7]["esc_power"].as<int>() << "\n";
+  if (subscription_names.find("esc_status") != subscription_names.end()) {
+    auto esc_status = data_container->subscription("esc_status");
+    for (const auto& sample : *esc_status) {
+      std::cout << "esc_power: " << sample["esc"][7]["esc_power"].as<int>() << "\n";
+    }
+  } else {
+    std::cout << "No esc_status subscription found\n";
   }
   return 0;
 }

examples/ulog_info.cpp

@@ -94,13 +94,6 @@ int main(int argc, char** argv)
       subscriptions.size());
   std::transform(subscriptions.begin(), subscriptions.end(), sorted_subscription_keys.begin(),
                  [](const auto& pair) { return pair.first; });
-  std::sort(sorted_subscription_keys.begin(), sorted_subscription_keys.end(),
-            [](const auto& a, const auto& b) {
-              if (a.name == b.name) {
-                return a.multi_id < b.multi_id;
-              }
-              return a.name < b.name;
-            });
   for (const auto& key : sorted_subscription_keys) {
     const auto& subscription = subscriptions.at(key);
     printf(" %s (%i)   -  %zu\n", key.name.c_str(), key.multi_id, subscription->size());

test/CMakeLists.txt

@@ -2,22 +2,17 @@
 
 include(FetchContent)
 
+set(SYSTEM_ARG SYSTEM)
 # cmake < 3.25 fails with system attribute
-if (CMAKE_VERSION VERSION_GREATER_EQUAL "3.25")
-	FetchContent_Declare(
-			DocTest
-			GIT_REPOSITORY "https://github.com/doctest/doctest.git"
-			GIT_TAG "v2.4.11"
-			SYSTEM
-	)
-
-else()
-	FetchContent_Declare(
-			DocTest
-			GIT_REPOSITORY "https://github.com/doctest/doctest.git"
-			GIT_TAG "v2.4.11"
-	)
+if (CMAKE_VERSION VERSION_LESS "3.25")
+	set(SYSTEM_ARG "")
 endif ()
+FetchContent_Declare(
+		DocTest
+		GIT_REPOSITORY "https://github.com/doctest/doctest.git"
+		GIT_TAG "v2.4.11"
+		${SYSTEM_ARG}
+)
 
 
 FetchContent_MakeAvailable(DocTest)

ulog_cpp/data_container.cpp

@@ -32,6 +32,15 @@ void DataContainer::headerComplete()
     message_info.field().resolveDefinition(_message_formats, 0);
   }
 
+  // try to resolve all fields for all multi message infos
+  for (auto& it : _message_info_multi) {
+    for (auto& message_infos_for_field : it.second) {
+      for (auto& message_info : message_infos_for_field) {
+        message_info.field().resolveDefinition(_message_formats, 0);
+      }
+    }
+  }
+
   // try to resolve all fields for params
   for (auto& it : _default_parameters) {
     auto& parameter = it.second;

ulog_cpp/data_container.hpp

@@ -5,6 +5,7 @@
 #pragma once
 
 #include <memory>
+#include <set>
 #include <unordered_map>
 #include <unordered_set>
 #include <vector>
@@ -23,7 +24,7 @@ class DataContainer : public DataHandlerInterface {
 
   struct NameAndMultiIdKey {
     std::string name;
-    int multi_id;
+    int multi_id{0};
 
     NameAndMultiIdKey() = default;
 
@@ -95,13 +96,13 @@ class DataContainer : public DataHandlerInterface {
     return _subscriptions_by_message_id;
   }
 
-  std::vector<std::string> subscriptionNames() const
+  std::set<std::string> subscriptionNames() const
   {
-    std::unordered_set<std::string> names;
+    std::set<std::string> names;
     for (const auto& kv : _subscriptions_by_name_and_multi_id) {
       names.insert(kv.first.name);
     }
-    return std::vector<std::string>(names.begin(), names.end());
+    return names;
   }
 
   std::shared_ptr<Subscription> subscription(const std::string& name, int multi_id) const

ulog_cpp/messages.hpp

@@ -247,7 +247,7 @@ class Field {
  * Since these types are only available at runtime, one can get the value as an std::variant,
  * and then do appropriate handling for each type. In case the user knows what type to expect,
  * it can also be explicitly casted to the desired type. In this case, any type conversion that is
- * allowed by `static_cast will` be performed.
+ * allowed by `static_cast` will be performed.
  *
  * Array types can be directly extracted as std::vector<T>, string types as std::string.
  */
@@ -346,7 +346,7 @@ class Value {
                 // return type is different from native type, but a vector
                 res.resize(arg.size());
                 for (std::size_t i = 0; i < arg.size(); i++) {
-                  res[i] = static_cast<typename ReturnType::value_type>(arg[i]);
+                  res[i] = staticCastEnsureUnsignedChar<typename ReturnType::value_type>(arg[i]);
                 }
               }
             } else {
@@ -362,7 +362,7 @@ class Value {
             if constexpr (is_vector<ReturnType>::value) {
               // return type is a vector
               res.resize(1);
-              res[0] = static_cast<typename ReturnType::value_type>(arg);
+              res[0] = staticCastEnsureUnsignedChar<typename ReturnType::value_type>(arg);
             } else {
               // return type is not a vector
               res = staticCastEnsureUnsignedChar<ReturnType>(arg);

ulog_cpp/reader.cpp

@@ -9,7 +9,7 @@
 
 #include "raw_messages.hpp"
 
-#if 1
+#if 0
 #define DBG_PRINTF(...) printf(__VA_ARGS__)
 #else
 #define DBG_PRINTF(...)

ulog_cpp/subscription.hpp

@@ -13,7 +13,7 @@ namespace ulog_cpp {
 /**
  * TypedDataView is a view on a Data object, which allows to access the data using the
  * MessageFormat meta definition. The subscription object only contains the Data object,
- * without repeated reference to the underlying MessageFormat, for storage efficiency reason.s
+ * without repeated reference to the underlying MessageFormat, for storage efficiency reasons.
  *
  * Note that TypedDataView should be a short-lived object solely to access data. As
  * it stores references to the underlying Data and MessageFormat objects, it is only valid