Failure w/TwainDSM.dll on OPENDSM when ProductName is NULL

[Travis]

When loading Twain_32.dll, I was able to pass a TW_IDENTITY structure representing the application (pOrigin) with the bare minimum values. All TW_STR32 values were initialized to NULL. A call to DG_CONTROL, DAT_PARENT, MSG_OPENDSM would succeed.

When loading TwainDSM.dll, passing the same initialized TW_IDENTITY structure representing the application (pOrigin) results in the twain function returning TWRC_FAILURE. If I simply put one character in the ProductName field, then the triplet succeeds.

Is this a bug or by design?

I’m using TWAINDSM.dll – 2.0.9.0

TW_IDENTITY AppID;



ZeroMemory(&AppID, sizeof(TW_IDENTITY));

AppID.Version.MajorNum = 1;

AppID.Version.MinorNum = 0;

AppID.Version.Language = TWLG_ENGLISH_USA;

AppID.Version.Country = TWCY_USA;

AppID.ProtocolMajor = TWON_PROTOCOLMAJOR;

AppID.ProtocolMinor = TWON_PROTOCOLMINOR;

AppID.SupportedGroups = DG_IMAGE | DG_CONTROL;



lstrcpy (AppID.Version.Info, _T("Version 1.0"));

lstrcpy(AppID.Manufacturer, _T("Manufacturer"));

lstrcpy(AppID.ProductFamily, _T("Product Family"));

Works:

lstrcpy(AppID.ProductName, "a");

Doesn’t not work:

lstrcpy(AppID.ProductName, ""); 

[retro]

Hi,

i am not a designer of twain, but according to the spec, which says:

The application must allocate a structure of type TW_IDENTITY and fill in all fields except
for the Id field. Once the structure is prepared, this
pOrigin parameter should point at that structure.

I would asume that it is expected that the Product name is not NULL.

I have seen this behavior myself and have corrected the TW_IDENTITY structure which is given to twain.

Nice regards,
Martin Haimberger

[Author]

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