add comments

src/shred.cpp

@@ -455,8 +455,10 @@ int Shred::shredDrive(Drive *drive, int *ipSignalFd)
 
             if ((d32Percent - d32TmpPercent) >= 0.01)
             {
+                // set shred percentage
                 drive->setTaskPercentage(d32TmpPercent);
                 d32TmpPercent = d32Percent;
+                // signal process in shredding
                 write(*ipSignalFd, "A", 1);
             }
 
@@ -563,7 +565,7 @@ double Shred::calcProgress()
     unsigned int uiMaxShredIteration = SHRED_ITERATIONS;
 
 #ifdef ZERO_CHECK
-    uiMaxShredIteration++;
+    uiMaxShredIteration++; // increment because we will check after SHRED_ITERATIONS the drive for non-zero bytes
 #endif
 
     if (this->ulDriveByteSize == 0)
@@ -641,6 +643,8 @@ unsigned int Shred::uiCalcChecksum(fileDescriptor file, Drive *drive, int *ipSig
     unsigned int uiChecksum = 0;
     unsigned long ulDriveByteCounter = 0U;
 
+    Logger::logThis()->info("Check-Task: Starting checksum verification - Drive: " + drive->getSerial());
+
 #ifdef ADAPTIVE_CHUNK_SIZE
     size_t checkChunkSize = CHUNK_SIZE_MAX;
 #else