implemented initial dpm core call functionality from module perspective

src/module_interface.cpp

@@ -0,0 +1,73 @@
+/**
+* @file module_interface.cpp
+* @brief Implementation of the module interface functions
+*
+* Provides the implementation of functions declared in the module interface
+* that are part of the DPM core, such as callback functions available to modules.
+*
+* @copyright Copyright (c) 2025 SILO GROUP LLC
+* @author Chris Punches <chris.punches@silogroup.org>
+*
+* Part of the Dark Horse Linux Package Manager (DPM)
+*
+* This program is free software: you can redistribute it and/or modify
+* it under the terms of the GNU Affero General Public License as
+* published by the Free Software Foundation, either version 3 of the
+* License, or (at your option) any later version.
+*
+* This program is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+* GNU Affero General Public License for more details.
+*
+* You should have received a copy of the GNU Affero General Public License
+* along with this program. If not, see <https://www.gnu.org/licenses/>.
+*
+* For bug reports or contributions, please contact the dhlp-contributors
+* mailing list at: https://lists.darkhorselinux.org/mailman/listinfo/dhlp-contributors
+*/
+
+#include "module_interface.hpp"
+#include <iostream>
+#include <string>
+
+/**
+ * @brief Function that modules can call to access DPM core functionality
+ *
+ * This function is exported by the DPM executable and can be called by
+ * dynamically loaded modules to access services or features of the core application.
+ *
+ * Note: In order for a module to use this functionality, it requires a forward declaration in the module:
+ * // Example:
+ * // Declaration of the DPM core function we want to call
+ *  extern "C" int dpm_core_callback(const char* action, const char* data);
+ *
+ * @param action The specific action or operation being requested
+ * @param data Additional data or parameters needed for the action
+ * @return Result code indicating success (0) or failure (non-zero)
+ */
+extern "C" int dpm_core_callback(const char* action, const char* data) {
+    // Implementation here
+    if (!action) {
+        std::cerr << "Error: Module callback received null action" << std::endl;
+        return 1;
+    }
+
+    std::string action_str(action);
+
+    if (action_str == "log") {
+        if (data) {
+            std::cout << "Module log: " << data << std::endl;
+        }
+        return 0;
+    }
+    else if (action_str == "get_config") {
+        if (data) {
+            std::cout << "Module requested config: " << data << std::endl;
+        }
+        return 0;
+    }
+
+    std::cerr << "Error: Unknown module callback action: " << action_str << std::endl;
+    return 1;
+}