// Set **destination** filesystem by uncommenting one of these:
    //#define DEST_FS_USES_SPIFFS
    //#define DEST_FS_USES_FFAT
    //#define DEST_FS_USES_SD
    //#define DEST_FS_USES_SD_MMC
    #define DEST_FS_USES_LITTLEFS
    #include <ESP32-targz.h>
    // filesystem object will be available as "tarGzFS"

    // mount spiffs (or any other filesystem)
    tarGzFS.begin();

    GzUnpacker *GZUnpacker = new GzUnpacker();

    GZUnpacker->haltOnError( true ); // stop on fail (manual restart/reset required)
    GZUnpacker->setupFSCallbacks( targzTotalBytesFn, targzFreeBytesFn ); // prevent the partition from exploding, recommended
    GZUnpacker->setGzProgressCallback( BaseUnpacker::defaultProgressCallback ); // targzNullProgressCallback or defaultProgressCallback
    GZUnpacker->setLoggerCallback( BaseUnpacker::targzPrintLoggerCallback  );    // gz log verbosity

    // expand one file
    if( !GZUnpacker->gzExpander(tarGzFS, "/gz_example.gz", tarGzFS, "/gz_example.jpg") ) {
      Serial.printf("gzExpander failed with return code #%d", GZUnpacker->tarGzGetError() );
    }

    // expand another file
    if( ! gzExpander(tarGzFS, "/blah.gz", tarGzFS, "/blah.jpg") ) {
      Serial.printf("operation failed with return code #%d", GZUnpacker->tarGzGetError() );
    }

    // mount spiffs (or any other filesystem)
    tarGzFS.begin();

    TarUnpacker *TARUnpacker = new TarUnpacker();

    TARUnpacker->haltOnError( true ); // stop on fail (manual restart/reset required)
    TARUnpacker->setTarVerify( true ); // true = enables health checks but slows down the overall process
    TARUnpacker->setupFSCallbacks( targzTotalBytesFn, targzFreeBytesFn ); // prevent the partition from exploding, recommended
    TARUnpacker->setTarProgressCallback( BaseUnpacker::defaultProgressCallback ); // prints the untarring progress for each individual file
    TARUnpacker->setTarStatusProgressCallback( BaseUnpacker::defaultTarStatusProgressCallback ); // print the filenames as they're expanded
    TARUnpacker->setTarMessageCallback( BaseUnpacker::targzPrintLoggerCallback ); // tar log verbosity

    if( !TARUnpacker->tarExpander(tarGzFS, "/tar_example.tar", tarGzFS, "/") ) {
      Serial.printf("tarExpander failed with return code #%d\n", TARUnpacker->tarGzGetError() );
    }

    // mount spiffs (or any other filesystem)
    tarGzFS.begin();

    TarGzUnpacker *TARGZUnpacker = new TarGzUnpacker();

    TARGZUnpacker->haltOnError( true ); // stop on fail (manual restart/reset required)
    TARGZUnpacker->setTarVerify( true ); // true = enables health checks but slows down the overall process
    TARGZUnpacker->setupFSCallbacks( targzTotalBytesFn, targzFreeBytesFn ); // prevent the partition from exploding, recommended
    TARGZUnpacker->setGzProgressCallback( BaseUnpacker::defaultProgressCallback ); // targzNullProgressCallback or defaultProgressCallback
    TARGZUnpacker->setLoggerCallback( BaseUnpacker::targzPrintLoggerCallback  );    // gz log verbosity
    TARGZUnpacker->setTarProgressCallback( BaseUnpacker::defaultProgressCallback ); // prints the untarring progress for each individual file
    TARGZUnpacker->setTarStatusProgressCallback( BaseUnpacker::defaultTarStatusProgressCallback ); // print the filenames as they're expanded
    TARGZUnpacker->setTarMessageCallback( BaseUnpacker::targzPrintLoggerCallback ); // tar log verbosity

    // using an intermediate file (default is /tmp/tmp.tar)
    if( !TARGZUnpacker->tarGzExpander(tarGzFS, "/targz_example.tar.gz", tarGzFS, "/tmp") ) {
      Serial.printf("tarGzExpander+intermediate file failed with return code #%d\n", TARGZUnpacker->tarGzGetError() );
    }

    // or without intermediate file
    if( !TARGZUnpacker->tarGzExpander(tarGzFS, "/targz_example.tar.gz", tarGzFS, "/tmp", nullptr ) ) {
      Serial.printf("tarGzExpander+intermediate file failed with return code #%d\n", TARGZUnpacker->tarGzGetError() );
    }

    // mount spiffs (or any other filesystem)
    tarGzFS.begin();

    GzUnpacker *GZUnpacker = new GzUnpacker();

    GZUnpacker->haltOnError( true ); // stop on fail (manual restart/reset required)
    GZUnpacker->setupFSCallbacks( targzTotalBytesFn, targzFreeBytesFn ); // prevent the partition from exploding, recommended
    GZUnpacker->setGzProgressCallback( BaseUnpacker::defaultProgressCallback ); // targzNullProgressCallback or defaultProgressCallback
    GZUnpacker->setLoggerCallback( BaseUnpacker::targzPrintLoggerCallback  );    // gz log verbosity

    if( ! GZUnpacker->gzUpdater(tarGzFS, firmwareFile, U_FLASH,/*don't restart after update*/false ) ) {
      Serial.printf("gzUpdater failed with return code #%d\n", GZUnpacker->tarGzGetError() );
    }

    // mount spiffs (or any other filesystem)
    tarGzFS.begin();

    fs::File file = tarGzFS.open( "/example_firmware.gz", "r" );

    if (!file) {
      Serial.println("Can't open file");
      return;
    }

    GzUnpacker *GZUnpacker = new GzUnpacker();

    GZUnpacker->haltOnError( true ); // stop on fail (manual restart/reset required)
    GZUnpacker->setupFSCallbacks( targzTotalBytesFn, targzFreeBytesFn ); // prevent the partition from exploding, recommended
    GZUnpacker->setGzProgressCallback( BaseUnpacker::defaultProgressCallback ); // targzNullProgressCallback or defaultProgressCallback
    GZUnpacker->setLoggerCallback( BaseUnpacker::targzPrintLoggerCallback  );    // gz log verbosity

    if( !GZUnpacker->gzStreamUpdater( (Stream *)&file, UPDATE_SIZE_UNKNOWN ) ) {
      Serial.printf("gzStreamUpdater failed with return code #%d\n", GZUnpacker->tarGzGetError() );
    }

    // mount spiffs (or any other filesystem)
    tarGzFS.begin();

    fs::File file = tarGzFS.open( "/example_archive.tgz", "r" );

    if (!file) {
      Serial.println("Can't open file");
      return;
    }

    TarGzUnpacker *TARGZUnpacker = new TarGzUnpacker();

    TARGZUnpacker->haltOnError( true ); // stop on fail (manual restart/reset required)
    TARGZUnpacker->setTarVerify( true ); // true = enables health checks but slows down the overall process
    TARGZUnpacker->setupFSCallbacks( targzTotalBytesFn, targzFreeBytesFn ); // prevent the partition from exploding, recommended
    TARGZUnpacker->setGzProgressCallback( BaseUnpacker::defaultProgressCallback ); // targzNullProgressCallback or defaultProgressCallback
    TARGZUnpacker->setLoggerCallback( BaseUnpacker::targzPrintLoggerCallback  );    // gz log verbosity
    TARGZUnpacker->setTarProgressCallback( BaseUnpacker::defaultProgressCallback ); // prints the untarring progress for each individual file
    TARGZUnpacker->setTarStatusProgressCallback( BaseUnpacker::defaultTarStatusProgressCallback ); // print the filenames as they're expanded
    TARGZUnpacker->setTarMessageCallback( BaseUnpacker::targzPrintLoggerCallback ); // tar log verbosity

    if( !TARGZUnpacker->tarGzStreamExpander( (Stream *)&file, tarGzFS ) ) {
      Serial.printf("tarGzStreamExpander failed with return code #%d\n", TARGZUnpacker->tarGzGetError() );
    }

    TarGzUnpacker *TARGZUnpacker = new TarGzUnpacker();

    TARGZUnpacker->haltOnError( true ); // stop on fail (manual restart/reset required)
    TARGZUnpacker->setTarVerify( false ); // nothing to verify as we're writing a partition
    TARGZUnpacker->setGzProgressCallback( BaseUnpacker::targzNullProgressCallback ); // don't care about gz progress
    TARGZUnpacker->setTarProgressCallback( BaseUnpacker::defaultProgressCallback ); // prints the untarring progress for each individual partition
    TARGZUnpacker->setTarStatusProgressCallback( BaseUnpacker::defaultTarStatusProgressCallback ); // print the filenames as they're expanded
    TARGZUnpacker->setTarMessageCallback( myTarMessageCallback/*BaseUnpacker::targzPrintLoggerCallback*/ ); // tar log verbosity

    // mount SD
    SD.begin();

    // this .tar.gz file has both the "app.ino.bin" and "app.spiffs.bin" partitions
    fs::File file = SD.open( "/bundle_firmware.tar.gz", "r" );

    if (!file) {
      Serial.println("Can't open file");
      return;
    }

    // this could also be a HTTP/HTTPS/UDP/Ethernet Stream
    Stream *streamptr = &file;

    if( !TARGZUnpacker->tarGzStreamUpdater( streamptr ) ) {
      Serial.printf("tarGzStreamUpdater failed with return code #%d\n", TARGZUnpacker->tarGzGetError() );
    } else {
      Serial.println( "Flashing successful, now restarting" );
      ESP.restart();
    }

    // basic progress callback (valid for tar or gzip)
    void myBasicProgressCallback( uint8_t progress )
    {
      Serial.printf("Progress: %d\n", progress );
    }


    // complex progress callback (valid for tar or gzip)
    void myProgressCallback( uint8_t progress )
    {
      static int8_t myLastProgress = -1;
      if( myLastProgress != progress ) {
        if( myLastProgress == -1 ) {
          Serial.print("Progress: ");
        }
        myLastProgress = progress;
        switch( progress ) {
          case   0: Serial.print("0% ▓");  break;
          case  25: Serial.print(" 25% ");break;
          case  50: Serial.print(" 50% ");break;
          case  75: Serial.print(" 75% ");break;
          case 100: Serial.print("▓ 100%\n"); myLastProgress = -1; break;
          default: if( progress < 100) Serial.print( "▓" ); break;
        }
      }
    }


    // General Error/Warning/Info logger
    void myLogger(const char* format, ...)
    {
      va_list args;
      va_start(args, format);
      vprintf(format, args);
      va_end(args);
    }


    // status callback for TAR (fired at file creation)
    void myTarStatusProgressCallback( const char* name, size_t size, size_t total_unpacked )
    {
      Serial.printf("[TAR] %-64s %8d bytes - %8d Total bytes\n", name, size, total_unpacked );
    }