Added possibility to set a pre save callback

CMakeLists.txt

@@ -6,7 +6,7 @@
 
 cmake_minimum_required(VERSION 3.16)
 project(robometry LANGUAGES C CXX
-                  VERSION 1.2.8)
+                  VERSION 1.3.0)
 
 include(GNUInstallDirs)
 include(FeatureSummary)

src/librobometry/include/robometry/BufferManager.h

@@ -501,12 +501,24 @@ class BufferManager {
 
     /**
      * @brief Set the saveCallback function. Thanks to this function you can save additional data
-     * type along with the matfile salve by telemetry
-     * @param[in] saveCallback The saveCallback function
+     * type along with the matfile saved by telemetry. This callback is called after saving the matfile.
+     * The callback receives as input the full path of the matfile just saved and the triggering method.
+     * The callback must return true on success, false otherwise.
+     * @param[in] saveCallback The saveCallback function.
      * @return true on success, false otherwise.
      */
     bool setSaveCallback(std::function<bool(const std::string&, const SaveCallbackSaveMethod& method)> saveCallback);
 
+    /**
+     * @brief Set the preSaveCallback function. Thanks to this function you can decide whether to proceed
+     * with the saving of the matfile or not. This callback is called before saving the matfile.
+     * The callback receives as input the triggering method.
+     * The callback must return true to proceed with the saving, false otherwise.
+     * @param[in] preSaveCallback The preSaveCallback function.
+     * @return true on success, false otherwise.
+     */
+    bool setPreSaveCallback(std::function<bool(const SaveCallbackSaveMethod& method)> preSaveCallback);
+
 
 private:
     static double DefaultClock();
@@ -547,6 +559,7 @@ class BufferManager {
 
     std::function<double(void)> m_nowFunction{DefaultClock};
     std::function<bool(const std::string&, const SaveCallbackSaveMethod& method)> m_saveCallback{};
+    std::function<bool(const SaveCallbackSaveMethod& method)> m_preSaveCallback {};
 
     std::thread m_save_thread;
     matioCpp::CellArray m_description_cell_array;

src/librobometry/src/BufferManager.cpp

@@ -32,10 +32,15 @@ robometry::BufferManager::~BufferManager() {
     }
     if (m_bufferConfig.auto_save) {
         std::string fileName;
-        saveToFile(fileName);
-        if (m_saveCallback)
-        {
-            m_saveCallback(fileName, SaveCallbackSaveMethod::last_call);
+        bool should_save = true;
+        if (m_preSaveCallback) {
+            should_save = m_preSaveCallback(SaveCallbackSaveMethod::last_call);
+        }
+        if (should_save) {
+            saveToFile(fileName);
+            if (m_saveCallback) {
+                m_saveCallback(fileName, SaveCallbackSaveMethod::last_call);
+            }
         }
     }
 }
@@ -223,7 +228,18 @@ bool robometry::BufferManager::setSaveCallback(std::function<bool (const std::st
     return true;
 }
 
-double robometry::BufferManager::DefaultClock() {
+bool robometry::BufferManager::setPreSaveCallback(std::function<bool(const SaveCallbackSaveMethod& method)> preSaveCallback)
+{
+    if (preSaveCallback == nullptr) {
+        std::cout << "Not valid preSaveCallback function." << std::endl;
+        return false;
+    }
+    m_preSaveCallback = preSaveCallback;
+    return true;
+}
+
+double robometry::BufferManager::DefaultClock()
+{
     return std::chrono::duration<double>(std::chrono::system_clock::now().time_since_epoch()).count();
 }
 
@@ -238,11 +254,19 @@ void robometry::BufferManager::periodicSave()
     {
         if (!m_tree->empty()) // if there are channels
         {
-            std::string fileName;
-            saveToFile(fileName, false);
-            if (m_saveCallback)
-            {
-                m_saveCallback(fileName, SaveCallbackSaveMethod::periodic);
+            bool should_save = true;
+            if (m_preSaveCallback) {
+                should_save = m_preSaveCallback(SaveCallbackSaveMethod::periodic);
+            }
+            if (should_save) {
+                std::string fileName;
+                saveToFile(fileName, false);
+                if (m_saveCallback) {
+                    m_saveCallback(fileName, SaveCallbackSaveMethod::periodic);
+                }
+            }
+            else {
+                std::cout << "Pre-save callback prevented the periodic save." << std::endl;
             }
         }
     }

test/BufferManagerTest.cpp

@@ -424,20 +424,30 @@ TEST_CASE("Buffer Manager Test")
 
     SECTION("Callback")
     {
-        robometry::BufferManager bm;
-        robometry::BufferConfig bufferConfig;
-        bufferConfig.n_samples = n_samples;
-        bufferConfig.filename = "buffer_manager_test_callback";
-        bufferConfig.auto_save = true;
-
-        REQUIRE(bm.addChannel({ "int_channel", {1}}));
-        bm.setSaveCallback(testCallback);
-        REQUIRE(bm.configure(bufferConfig));
+        bool called = false;
 
-        for (int i = 0; i < 10; i++) {
-            bm.push_back(i, "int_channel");
-            std::this_thread::sleep_for(std::chrono::milliseconds(10));
+        {
+            robometry::BufferManager bm;
+            robometry::BufferConfig bufferConfig;
+            bufferConfig.n_samples = n_samples;
+            bufferConfig.filename = "buffer_manager_test_callback";
+            bufferConfig.auto_save = true;
+
+            REQUIRE(bm.addChannel({ "int_channel", {1}}));
+            REQUIRE(bm.setSaveCallback(testCallback));
+            REQUIRE(bm.setPreSaveCallback([&called](const robometry::SaveCallbackSaveMethod& /**method*/)
+            {
+                called = true;
+                return true;
+            }));
+            REQUIRE(bm.configure(bufferConfig));
+
+            for (int i = 0; i < 10; i++) {
+                bm.push_back(i, "int_channel");
+                std::this_thread::sleep_for(std::chrono::milliseconds(10));
+            }
         }
+        REQUIRE(called);
     }
 
     SECTION("Unit of measure") {