Class libraries not aware of LUA

[This is a reproduction of a message in my old blog. With the imminent release of Delphi 2007, I am really interested to see if they have addressed this and how.]

Many frameworks have provided class wrapper to deal with Windows Registry access and many, including the ATL's CRegKey and Borland's Delphi TRegistry have a problem in dealling with registry access in LUA (Least-Privilege Users Account).

Not that they do not have facility to deal with this but the default security access rights is set too high making unwary developers that do not develop in LUA falling into the pitfall.

For ATL::CRegKey::Open() it is default to KEY_READ | KEY_WRITE and TRegistry.OpenKey uses as its TRegistry.Access which has a default value of the same.

What makes Borland's class not capable in dealing with LUA failure than that in ATL is the return value of these respective member functions. CRegKey::Open() returns the value from ::RegOpenKeyEx(), the raw API, which Borland returns a Boolean which is true if the API returns ERROR_SUCCESS. In so doing Borland has discarded the vital information that can allow the caller to take appropriate action.

For example, when using default security access value, the CRegKey::Open() returns 0x5 for an existing key in HKLM and this means "Access is denied". If the key does not exist and that you have access rights, the return value is 0x2. In the case of Borland's TRegistry.OpenKey(), all it can return is false to indicate if something is wrong. What's wrong is that the caller is unable to determine through the lack of information. Hence in many of Borland's usage, when it fails to gain access to the HKLM with the default access rights, it will simply assumes that the key does not exist and hence performing the wrong recovery routine!

Given that Borland has already published this interface, it cannot change it. At best, it can add a read-only property to allow caller to query it after the operation but this requires code to change. Oops!!! One such Borland's library function that causing me grieve with LUA is the BDE.DbiInit().

I am just wondering if Borland's developer developing their products in LUA or in Admin accounts. From what I have seen, obviously the former.