#289 TEdit::LockBuffer is used in an exception-unsafe manner

[Vidar Hasfjord]

The use of TEdit::LockBuffer and UnlockBuffer requires exception handling in case an exception is thrown in the intermediate code, but none of the code using these functions does so.

As of revision 2868, this issue affects the following functions:

• TEdit::EvChar, EvKeyDown, EvUpDown, IsValid and Search.
• TEditFile::Read and Write
• TEditView::LoadData and VnCommit.

Note that this issue does not affect the Owlet branch, as LockBuffer and UnlockBuffer were eliminated on that branch in [r2160].

Elimination of TEdit::LockBuffer and UnlockBuffer is probably a good way of resolving this issue. The implementation currently boils down to GetText and SetText, since GetMemHandle (EM_GETHANDLE) has lots of special conditions that makes it unreliable as a general solution. Hence the removal in Owlet.

[Joe Slater]

Hi Vidar,

I agree with your solution, along with the reasons given in [r2160]. In real-life situations, it just doesn't seem to be needed.