🚀 go-pugleaf

Hi All,

I have an application that detects when digital cameras are connected and 
copies file from them.  Currently it works with plug in play cameras that 
use USB storage and I am now working on a Still Image version.  I have the 
Still Image handler code working and I can detect what USB port the camera 
is on, but I am unable to read from that port.  Basically what I want to do 
is use windows.CreateFile passing the USB port in the format of //./Usbscan 
and then query and read from this location.  Below is a sample application 
that uses CreateFile and then attempts to get pipe information from the file 
handle using DeviceIOControl.  The CreateFile call works without issue, but 
I am getting an error, 87 - Parameter incorrect, on the DeviceIOControl 
call.  I have tried all combination of params I can think of to no avail. 
Hopefully someone out there has done something similar...  Here is the code:

unit Demo;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls;

{ start USBSCAN.h translation }
const

  FILE_DEVICE_USB_SCAN = $8000;
  IOCTL_INDEX = $0800;
  METHOD_BUFFERED = 0;
  FILE_ANY_ACCESS = 0;
  MAX_NUM_PIPES = 8;

  IOCTL_GET_PIPE_CONFIGURATION =
    (FILE_DEVICE_USB_SCAN SHL 16)  OR
    (FILE_ANY_ACCESS SHL 14) OR
    ((IOCTL_INDEX + 10) SHL 2) or METHOD_BUFFERED;
    //CTL_CODE(FILE_DEVICE_USB_SCAN, IOCTL_INDEX + 
10,METHOD_BUFFERED,FILE_ANY_ACCESS);

type
  _RAW_PIPE_TYPE = (
    USBSCAN_PIPE_CONTROL,
    USBSCAN_PIPE_ISOCHRONOUS,
    USBSCAN_PIPE_BULK,
    USBSCAN_PIPE_INTERRUPT  );

  _USBSCAN_PIPE_INFORMATION = record
    MaximumPacketSize: Word;
    EndpointAddress: UCHAR;
    Interval: UCHAR;
    PipeType: _RAW_PIPE_TYPE;
  end {_USBSCAN_PIPE_INFORMATION};
  USBSCAN_PIPE_INFORMATION = _USBSCAN_PIPE_INFORMATION;
  PUSBSCAN_PIPE_INFORMATION = ^_USBSCAN_PIPE_INFORMATION;

  _USBSCAN_PIPE_CONFIGURATION = record
    NumberOfPipes: ULONG;
    PipeInfo: Array[0..MAX_NUM_PIPES-1] of USBSCAN_PIPE_INFORMATION;
  end {_USBSCAN_PIPE_CONFIGURATION};
  USBSCAN_PIPE_CONFIGURATION = _USBSCAN_PIPE_CONFIGURATION;
  PUSBSCAN_PIPE_CONFIGURATION = ^_USBSCAN_PIPE_CONFIGURATION;

{ end USBSCAN.h translation }

type
  TForm1 = class(TForm)
    Button1: TButton;
    Memo1: TMemo;
    Edit1: TEdit;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);
var
     hres: HRESULT;
     srcHandle: THandle;
     usbScanPipeInfo : USBSCAN_PIPE_CONFIGURATION;
     overlapped : TOverlapped;
     bytesReturned: DWORD;
     b : boolean;
     pt : _RAW_PIPE_TYPE;
begin
  memo1.lines.clear();
  memo1.lines.Add(format('USBSCAN_PIPE_CONFIGURATION 
size:%s',[inttostr(sizeof(USBSCAN_PIPE_CONFIGURATION))]));
  memo1.lines.Add(format('USBSCAN_PIPE_INFORMATION 
size:%s',[inttostr(sizeof(USBSCAN_PIPE_INFORMATION))]));

  // Initialize Overlapped structure
  FillChar(overlapped, SizeOf(overlapped), #0);
  overlapped.hEvent := CreateEvent(nil, True, False, nil);

  srcHandle := CreateFile(
                    PChar(edit1.text),   // format = //./Usbscanx
                    GENERIC_READ,
                    FILE_SHARE_READ,
                    nil,
                    OPEN_EXISTING,
                    FILE_ATTRIBUTE_NORMAL {OR FILE_FLAG_OVERLAPPED},
                    0
                   );

  memo1.lines.Add(format('CreateFile LastError 
size:%s',[inttostr(getlasterror ())]));

  b := DeviceIoControl(
         srcHandle,
         DWORD(IOCTL_GET_PIPE_CONFIGURATION),
         nil,
         0,
         @usbScanPipeInfo,
         sizeof(USBSCAN_PIPE_CONFIGURATION),
         bytesReturned,
         //@overlapped    // if FLAG FILE_FLAG_OVERLAPPED set in CreateFile
         nil
        );

  memo1.lines.Add(format('DeviceIoControl LastError 
size:%s',[inttostr(getlasterror ())]));

  CloseHandle(srcHandle);

  SetEvent(overlapped.hEvent);
  CloseHandle(overlapped.hEvent);

end;

end.