Index: sources/storage/FileHandler.cpp
===================================================================
diff -u -r4a67c01045f365be38f1a12a8572c0070d343e1e -rcf51c19d82d667644d7f70eaa521b43f908c7068
--- sources/storage/FileHandler.cpp	(.../FileHandler.cpp)	(revision 4a67c01045f365be38f1a12a8572c0070d343e1e)
+++ sources/storage/FileHandler.cpp	(.../FileHandler.cpp)	(revision cf51c19d82d667644d7f70eaa521b43f908c7068)
@@ -1,31 +1,29 @@
 /*!
  *
- * Copyright (c) 2020-2022 Diality Inc. - All Rights Reserved.
+ * Copyright (c) 2020-2023 Diality Inc. - All Rights Reserved.
  * \copyright
  * THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
  * WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
  *
  * \file    FileHandler.cpp
  * \author  (last)      Behrouz NematiPour
- * \date    (last)      24-Feb-2022
+ * \date    (last)      22-Jan-2023
  * \author  (original)  Behrouz NematiPour
  * \date    (original)  26-Aug-2020
  *
  */
 #include "FileHandler.h"
 
 //Qt
-#include <QFile>
 #include <QTextStream>
 #include <QProcess>
 #include <QDate>
-#include <QDir>
-#include <QDebug>
 #include <QStorageInfo>
 
 
 // Project
 // #include "Logger.h" // logger should not be used in this class.
+#include "StorageGlobals.h"
 
 // namespace
 using namespace Storage;
@@ -52,7 +50,7 @@
             << QDate::currentDate().toString("yyyy_MM_dd")   << " "
             << QTime::currentTime().toString("HH:mm:ss"  )   << " "
             << mCritical
-            << endl;
+            << Qt::endl;
     }
     ++count;
 }
@@ -93,7 +91,7 @@
  * \param   vContent  - The content of the file which will be set when done.
  * \return  false if file cannot be opened.
  */
-bool FileHandler::read(const QString &vFileName, QString &vContent)
+bool FileHandler::read(const QString &vFileName, QString &vContent, bool vAppend)
 {
     QFile file(vFileName);
     if (! file.open(QFile::Text | QFile::ReadOnly)) {
@@ -103,7 +101,12 @@
         return false;
     }
     QTextStream in(&file);
-    vContent = in.readAll();
+    if ( vAppend ) {
+        vContent += in.readAll();
+    }
+    else {
+        vContent  = in.readAll();
+    }
     return true;
 }
 
@@ -263,7 +266,6 @@
  */
 bool FileHandler::isMounted(const QString &vPath, bool *vIsReadOnly)
 {
-    // disabled coco begin validated: Needed User Interaction to make the device not ready so tested manually
     bool mounted = false;
     // removing the extra '/' from the vPath if there is to be able to compare to the root path of the storage
     QString path = vPath.trimmed();
@@ -272,7 +274,11 @@
     if (path.at(lastIndex) == "/") path.remove(lastIndex, 1);
     // check to see if the path in the list of mounted rootPaths
     /// DEBUG: qDebug() << " +++++ " << QStorageInfo::mountedVolumes();
-    foreach (const QStorageInfo &storage, QStorageInfo::mountedVolumes()) {
+    // FIXME :  This function blocks the Device controller thread
+    //          It has been observed during the USB plug test and getting the drive info(space) that
+    //          immediately after the mount this function laggs to get the information for about 2-5 sec.
+    auto mountedVolumes = QStorageInfo::mountedVolumes();
+    foreach (const QStorageInfo &storage, mountedVolumes) {
         if (storage.isValid() && storage.isReady()) {
             if ( storage.rootPath() == path ) {
                 if (vIsReadOnly) *vIsReadOnly = storage.isReadOnly();
@@ -283,9 +289,36 @@
     }
     return mounted;
 }
-// disabled coco end
 
 /*!
+ * \brief   FileHandler::tmpUsable
+ * \details Checks if the temp folder is available for read and write to file and directory
+ * \note    This function will only chek the temp folder usability once
+ *          and next call will just return the first result,
+ *          assuming that the temp file situation is not going to change and is stable.
+ * \return  true on success
+ */
+bool FileHandler::tmpUsable()
+{
+    static bool ok      = false;
+    static bool tested  = false;
+    if ( tested )  return ok;
+
+    QString tmp     = Storage::Standard_tmp;
+    QString tmpTestFolder   = tmp + "tmp_test_folder" ;
+    QString tmpTestFile     = tmp + "tmp_test_file"   ;
+    QString tmpTestContent  =       "tmp_test_content";
+    QDir dir(tmp);
+    if ( ! dir.exists()                                              ) { ok = false; goto lOut; }
+    if ( ! FileHandler::makeFolder  (tmpTestFolder                  )) { ok = false; goto lOut; }
+    if ( ! FileHandler::write       (tmpTestFile  , tmpTestContent  )) { ok = false; goto lOut; }
+    if ( ! FileHandler::read        (tmpTestFolder, tmpTestContent  )) { ok = false; goto lOut; }
+lOut:
+    tested = true;
+    return ok;
+}
+
+/*!
  * \brief   FileHandler::find
  * \details The function to find files.
  *          It mainly been implemented to find the files are using some amount of total storage in the vPath by percentage,
@@ -339,7 +372,7 @@
     // if it is breaks
     // else adds the file to the list and continues.
     // DEBUG: qDebug() << "%" << totalSizeStorage << totalSizeFiles << totalSizeRetain << totalSizeFiles - totalSizeRetain << vRetainPercent;
-    quint64 totalSizeRemoved = 0;
+    quint64 totalSizeRemoved = 0; Q_UNUSED(totalSizeRemoved);
     for (auto it = fileInfoListAll.crbegin(); it != fileInfoListAll.crend(); ++it) {
         // (totalSizeFiles <= totalSizeRetain) has been checked above and didn't return; ,
         // so at least one file should be checked and then check again in the loop.