"Willy Denoyette [MVP]" <willy.denoyette@telenet.be> wrote in message
news:OAFvqaZsHHA.4800@TK2MSFTNGP05.phx.gbl...
> "Pucca" <Pucca@discussions.microsoft.com> wrote in message
> news:D206962A-0EFE-4B5C-858E-AE357A42E487@microsoft.com...
>> Hi, I'm using vs2005, .net 2, C# for Windows application. I use
>> DllImport so
>> I can call up a function written in C++ as unmanaged code and compiled as
>> a
>> dll us vs2005. My application is able to call the function,
>> EncodeAsnUser.
>> And it's returning OK but when I display the decoded data in another part
>> of
>> my application it shows no data has been decoded, all fiedls are either
>> null
>> or blanks. For some reason, I am not able to step through this
>> function's
>> code. However, I can see the userContextData does hold all the data that
>> I
>> assigned and that it's passing.
>> I think the pbroblems is with my declaration of the parameters(blob and
>> the
>> userdata structure) .
>> 1. Am I passing the userContextData as a pointer to the function?
>> 2. Am I allocating memory correctly for the Blob?
>> 3. Am I passing the Blob** correctly?
>> Can someone see what I need to correct here to make it work? Thank you.
>>
>> [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
>> public class CUserContextData
>> {
>> public int bWinLogOn = 0;
>> public int bUnifiedID = 0;
>>
>> [MarshalAs(UnmanagedType.ByValTStr, SizeConst =
>> MAX_ADSPATH_CHARS)]
>> public String shell = null;
>> [MarshalAs(UnmanagedType.ByValTStr, SizeConst =
>> MAX_ADSPATH_CHARS)]
>> public String homeDir = null;
>> [MarshalAs(UnmanagedType.ByValTStr, SizeConst =
>> MAX_ADSPATH_CHARS)]
>> public String primaryGroupSID = null;
>> [MarshalAs(UnmanagedType.ByValTStr, SizeConst =
>> MAX_ADSPATH_CHARS)]
>> public String LoginName = null;
>>
>> public int symarkUID = 0; //Unified User ID
>> public int IID = 0; //Independant ID
>> public int Revision = 0;
>> }
>>
>> public struct Blob
>> {
>> public IntPtr pData;
>> public int nLength;
>> public int nSize;
>> }
>>
>> public class LibWrap
>> {
>> [DllImport("UnityDecodeAsnUser.dll", CharSet =
>> CharSet.Unicode)]
>> public static extern DE_ERRORS EncodeAsnUser(ref Blob blob,
>> [In, Out]CUserContextData m);
>> }
>>
>> // create an instance of the Blob structure
>> CUnityDS.Blob blob = new CUnityDS.Blob();
>> //Encode the user data into a blob
>> int nBytes =
>> Marshal.SizeOf(typeof(CUnityDS.Blob));
>> IntPtr ptr = Marshal.AllocHGlobal(nBytes);
>>
>>
>> // copy and pin the structure to that location
>> Marshal.StructureToPtr(blob, ptr, true);
>>
>> // Pass it by reference
>> // OK, now it's time to "reconsitute" the
>> structure
>> blob = (CUnityDS.Blob)Marshal.PtrToStructure(ptr,
>> typeof(CUnityDS.Blob));
>>
>>
>> CUnityDS.DE_ERRORS errcode =
>> CUnityDS.DE_ERRORS.DE_MEMORY_ALLOCATION_FAILURE;
>> errcode = CUnityDS.LibWrap.EncodeAsnUser(ref blob,
>> userContextData);
>>
>> //Convert from IntPtr data to byte[] which is
>> needed
>> for adding as meetingBlob
>> int size = Marshal.SizeOf(blob);
>> byte[] meetingBlob = new byte[size];
>>
>> System.Runtime.InteropServices.Marshal.Copy(blob.pData, meetingBlob, 0,
>> size);
>> //add the blob
>>
>> deNewContextObject.Properties["meetingBlob"].Add((object)meetingBlob);
>>
>> deNewContextObject.CommitChanges();
>>
>> //This is the C++ function that I'm calling
>> extern "C" DE_ERRORS __declspec(dllexport)EncodeAsnUser(Blob** ppBlob,
>> CUserContextData *userData)
>> {
>> _bstr_t temp;
>> AsnData* pAsn;
>> std::wstring wsUID;
>> int REVISION=0;
>> const char* EMPTY_STRING;
>> EMPTY_STRING = "";
>>
>> if ( ( pAsn = AsnAlloc( NULL ) ) == NULL )
>> {
>> DbgLog( DL_ERROR, "Unable to allocate ASN.1 buffer" );
>> return DE_MEMORY_ALLOCATION_FAILURE;
>> }
>> if ( !AsnPushTag(pAsn, (ASN_TAG$APPLICATION_START) ) )
>> goto failed;
>>
>> if (!AsnWriteInteger( pAsn, REVISION))
>> goto failed;
>>
>> if(userData->bUnifiedID)//use UID
>> {
>> if (!AsnWriteInteger( pAsn, True) )
>> goto failed;
>> }
>> else //use indep ID
>> {
>> if (!AsnWriteInteger( pAsn, False) )
>> goto failed;
>> }
>> if(userData->IID == NULL)
>> {
>> if ( !AsnWriteGeneralString( pAsn, EMPTY_STRING))
>> goto failed;
>> }
>> else
>> {
>> _bstr_t bstrtUID = L"0"; //initilize the bstr
>> _itow(userData->IID, bstrtUID, 10);
>>
>> if ( !AsnWriteGeneralString( pAsn, (char*)bstrtUID))
>> goto failed;
>> }
>>
>> //WinUser name
>> if(userData->bWinLogOn)
>> {
>> if (!AsnWriteInteger( pAsn, True) )
>> goto failed;
>>
>> }
>> else//use indep User Name
>> {
>> if (!AsnWriteInteger( pAsn, False) )
>> goto failed;
>> }
>>
>> //Geco
>> if ( !AsnWriteGeneralString( pAsn, EMPTY_STRING))
>> goto failed;
>>
>> //Shell
>> temp = userData->shell;
>> if ( !AsnWriteGeneralString( pAsn, (char*)temp))
>> goto failed;
>>
>> //Home Driectory
>> temp = userData->homeDir;
>> if ( !AsnWriteGeneralString( pAsn, (char*)temp))
>> goto failed;
>>
>> //Primary Group SID
>> temp = userData->primaryGroupSID;
>> if (!AsnWriteGeneralString( pAsn, (char*)temp))
>> goto failed;
>>
>> if ( !AsnPopTag( pAsn ) )
>> goto failed;
>> *ppBlob = AsnExtractData( pAsn );
>> AsnFree( pAsn );
>> return DE_SUCCESS;
>>
>> failed:
>> DbgLog(DL_ERROR, "Failed to encode ASN.1 message packet" );
>> AsnFree( pAsn );
>> return DE_ENCODE_MESSAGE_PACKET_FAILURE;
>> --
>> Thanks.
>
>
>
> Pucca, You have a wrong idea abut how the Blob structure looks like.
> This struct holds a pointer and two integers, that means it's length is 12
> bytes (in a 32 bit application), while you think that this struct holds
> the actual data of the blob on return, it just holds a pointer to the data
> and (I assume) the length of the actual data in nLength and the length of
> the buffer for the data in nSize.
>
> Note that here I assume that the "AsnExtractData" function called in the
> EncodeAsnUser function effectively fills the Blob with the data pointer
> and the size of the data in the buffer and the size of buffer .
>
> One way to get at the Blob and the Data is shown in the followin:
>
> [DllImport(...]