dokan limit speed, but windows10 pop-up never displays progress

[zhongguo1987]

I want to implement a file copying speed limit for Dokan。Specially modified the DispatcheWrite function in write. c of the dokan dll project。Copy the file successfully，But the Windows pop-up window never displays progress information.why,thank you

DispatcheWrite is modified as follows

#define MIN(i, j) (((i) < (j)) ? (i) : (j))
#define SPEED_LIMIT (128 * 1024)  

VOID DispatchWrite(PDOKAN_IO_EVENT IoEvent) {
  PDOKAN_IO_BATCH writeIoBatch = IoEvent->IoBatch;
  ULONG writtenLength = 0;
  NTSTATUS status = STATUS_SUCCESS;

  CreateDispatchCommon(IoEvent, 0, /*UseExtraMemoryPool=*/FALSE,
                       /*ClearNonPoolBuffer=*/TRUE);

  CheckFileName(IoEvent->EventContext->Operation.Write.FileName);
  DbgPrint(
      "###WriteFile file handle = 0x%p, eventID = %04d, event Info = 0x%p\n",
      IoEvent->DokanOpenInfo,
      IoEvent->DokanOpenInfo != NULL ? IoEvent->DokanOpenInfo->EventId : -1,
      IoEvent);

  // Since driver requested bigger memory,
  // allocate enough memory and send it to driver
  if (IoEvent->EventContext->Operation.Write.RequestLength > 0) {
    DWORD error = SendWriteRequest(
        IoEvent, IoEvent->EventContext->Operation.Write.RequestLength,
        &writeIoBatch);
    if (error != ERROR_SUCCESS) {
      if (error != ERROR_NO_SYSTEM_RESOURCES) {
        free(writeIoBatch);
      }
      if (error == ERROR_OPERATION_ABORTED) {
        IoEvent->EventResult->Status = STATUS_CANCELLED;
        DbgPrint(
            "WriteFile Error : User should already canceled the operation. "
            "Return STATUS_CANCELLED. \n");
      } else {
        IoEvent->EventResult->Status = DokanNtStatusFromWin32(error);
        DbgPrint("Unknown SendWriteRequest Error : LastError from "
                 "SendWriteRequest = %lu. \nUnknown SendWriteRequest error : "
                 "EventContext had been destoryed. Status = %X. \n",
                 error, IoEvent->EventResult->Status);
      }
      EventCompletion(IoEvent);
      return;
    }
  }
  ULONG havewritelen = 0;
  // for the case SendWriteRequest success
  if (IoEvent->DokanInstance->DokanOperations->WriteFile) {

#if 0
    status = IoEvent->DokanInstance->DokanOperations->WriteFile(
        writeIoBatch->EventContext->Operation.Write.FileName,
        (PCHAR)writeIoBatch->EventContext +
            writeIoBatch->EventContext->Operation.Write.BufferOffset,
        writeIoBatch->EventContext->Operation.Write.BufferLength,
        &writtenLength,
        writeIoBatch->EventContext->Operation.Write.ByteOffset.QuadPart,
        &IoEvent->DokanFileInfo);
#else
    ULONG remainingBytes =
        writeIoBatch->EventContext->Operation.Write.BufferLength;
    LONGLONG currentOffset =
        writeIoBatch->EventContext->Operation.Write.ByteOffset.QuadPart;
    PCHAR currentBuffer =
        (PCHAR)writeIoBatch->EventContext +
        writeIoBatch->EventContext->Operation.Write.BufferOffset;
    while (remainingBytes > 0) {

      DWORD bytesToWrite =
          MIN(remainingBytes,
              SPEED_LIMIT); 
      DWORD writtenLength = 0;
      status = IoEvent->DokanInstance->DokanOperations->WriteFile(
          writeIoBatch->EventContext->Operation.Write.FileName, currentBuffer,
          bytesToWrite, &writtenLength, currentOffset, &IoEvent->DokanFileInfo);

      remainingBytes -= writtenLength;
      currentOffset += writtenLength;
      currentBuffer += writtenLength;

      havewritelen += writtenLength;

      DWORD delayMs = (DWORD)(1000.0 * writtenLength /
                              SPEED_LIMIT);
      Sleep(delayMs);
    }

#endif
  } else {
    status = STATUS_NOT_IMPLEMENTED;
  }

  IoEvent->EventResult->Status = status;
  IoEvent->EventResult->BufferLength = 0;

  if (status == STATUS_SUCCESS) {
    IoEvent->EventResult->BufferLength = havewritelen;
    IoEvent->EventResult->Operation.Write.CurrentByteOffset.QuadPart =
        writeIoBatch->EventContext->Operation.Write.ByteOffset.QuadPart +
        havewritelen;
  }

  if (writeIoBatch != IoEvent->IoBatch) {
    PushIoBatchBuffer(writeIoBatch);
  }

  EventCompletion(IoEvent);
}

[Liryna]

If EventCompletion is called with the same argument / result as the original implementation, there should be no issue.
Does the progress hang ? Could it be possible the while (remainingBytes > 0) never returns ?

[zhongguo1987]

The current writing style of the warehouse is completely normal, but the speed of copying files is too fast. What I need to implement is to limit the speed of copying files. Is there any way to reduce the speed of copying files.

[zhongguo1987]

I have changed it now in order to slow down the copying speed through delay, but the progress box for copying files will appear on the Windows 10 system, and the speed of copying files will not be displayed. I don't know why, I need help. Or from the implementation of Dokan, see if there are any ways to reduce the file copying rate

[Liryna]

Adding a sleep or delay in your implementation should just work. I added a Sleep(500) here

dokany/samples/dokan_memfs/memfs_operations.cpp

Line 332 in 6a412d7

auto filenodes = GET_FS_INSTANCE;

and it worked. Changed it to Sleep(1000) and speed was reduced by half as expected.