fix time too short (0s)

Author: hurui200320

README.md

@@ -203,7 +203,7 @@ Here is my workflow:
 3. Use `oam media local walk -au <path/to/local/data>` to generate a reference hash on the correct data (assuming data on your local drive is correct)
 4. Use `oam media <barcode> walk -au <path/to/ltfs>` to calculate the hash of files on tape, then store in the database.
 5. Use `oam file check -m local -m <barcode> -n 2` to exam if every file is matched. This command should have no output if everything is correct.
-6. Then copy the sample data to other two tapes. I keep 3 copies of the same data to ensure safety.
+6. Then copy the sample data to other two tapes and check. I keep 3 copies of the same data to ensure safety.
 
 Tips:
 + Using tools like TeraCopy, you can leave a checksum file on the tape. So I can check the file even I lost the database of this software.

src/main/kotlin/info/skyblond/oam/command/media/WalkCommand.kt

@@ -19,6 +19,7 @@ import org.jetbrains.exposed.sql.transactions.transaction
 import java.util.*
 import kotlin.io.path.fileSize
 import kotlin.io.path.relativeToOrNull
+import kotlin.math.max
 
 object WalkCommand : CliktCommand(
     help = "Walk a given media to append, update or verify files."
@@ -95,7 +96,7 @@ object WalkCommand : CliktCommand(
                 echo("[I]Calculating hash for $relativePathString")
                 val t = System.currentTimeMillis() / 1000
                 val hash = p.sha3(bufferSize * MB)
-                val dt = System.currentTimeMillis() / 1000 - t
+                val dt = max(1, System.currentTimeMillis() / 1000 - t)
                 echo(
                     "[I]Finished $relativePathString, " +
                             "$dt s, ${size / 1024 / 1024 / dt} MB/s"