move the chroot logic to a separate agent to fix the update process chroot bugs

Author: UriHerrera

include/nuts/SystemInterface.h

@@ -38,6 +38,11 @@ class NUTS_EXPORT SystemInterface : public QObject {
     // Overlay operations
     bool executeInOverlay(const QStringList& command, QString& output, QString& error);
 
+    // Long-running variant for the single agent call.
+    // Timeout defaults to 7200000 ms (2 hours) to cover the full update pipeline.
+    bool executeInOverlayAgent(const QStringList& command, QString& output,
+                               QString& error, int timeout = 7200000);
+
     // File operations
     bool downloadFile(const QString& url, const QString& destination);
     QString calculateMD5(const QString& filePath);

include/nuts/UpdateManager.h

@@ -47,21 +47,17 @@ class NUTS_EXPORT UpdateManager : public QObject {
     QString m_updateUrl;
     QString m_updateChecksum;
     QString m_otaChecksum;
-    QString m_pkgManagerPath;
     QStringList m_mirrorList;
     QMap<QString, QString> m_queryData;
 
-    // Helper methods for update process
+    // Pre-chroot helpers (run on host)
     bool checkDiskSpace();
-    bool prepareSystemPartitions();
-    bool downloadOTAPayload();
-    bool verifySquashFSIntegrity(const QString& squashfsPath);
-    bool mountOTAPayload();
-    bool prepareUpdateTools();
-    bool syncPackageData();
-    bool performPackageUpdates();
-    bool runCleanupCrew();
-    void cleanup();
+
+    // Write the parameter file for nuts-agent and launch it in a single chroot session.
+    bool writeAgentParams(const QString& filePath, bool hasNvidia) const;
+
+    // Parse structured output from nuts-agent and relay progress signals.
+    void parseAndRelayAgentOutput(const QString& output);
 
     // Version comparison helper
     static int compareVersions(const QString& version1, const QString& version2);

src/CMakeLists.txt

@@ -1,6 +1,9 @@
 # Library
 add_subdirectory(lib)
 
+# Agent (single-session chroot binary)
+add_subdirectory(agent)
+
 # Helper (privileged backend)
 add_subdirectory(helper)
 

src/agent/CMakeLists.txt

@@ -0,0 +1,20 @@
+set(AGENT_SOURCES
+    main.cpp
+    NutsAgent.cpp
+)
+
+add_executable(nuts-agent ${AGENT_SOURCES})
+
+target_include_directories(nuts-agent
+    PRIVATE
+        ${CMAKE_SOURCE_DIR}/include
+)
+
+target_link_libraries(nuts-agent
+    PRIVATE
+        Qt6::Core
+)
+
+install(TARGETS nuts-agent
+    RUNTIME DESTINATION ${CMAKE_INSTALL_SBINDIR}
+)