X11 Clipboard implementation

[Ulrich Czekalla]

On Wed, 2003-02-12 at 05:22, Mike Hearn wrote:
> Hi all,
> 
> I've been poking around inside the wine clipboard system, in an attempt
> to make it properly compliant with the agreed upon specs over at 
> 
> http://www.freedesktop.org/standards/clipboards.txt
> 
> At the moment, Wine mixes up CLIPBOARD and PRIMARY, which is not a good
> idea. Ideally, Wine would work like GTK, Qt, Mozilla and all the rest
> do, which is to keep CLIPBOARD for ctrl-c, ctrl-v type operations, and
> primary for selected text/middle click.
>
> When you select some text in say notepad, both CLIPBOARD and PRIMARY are
> grabbed, which is wrong, only primary should be grabbed. In a similar
> fashion, when you select Edit | Copy only CLIPBOARD should be grabbed.
> 
> Currently, selecting text in Wine doesn't do anything (at least, not in
> notepad). So, the obvious way to fix that would be to introduce a new
> Wine-specific API, that lets the Wine controls call SetSelectedText or
> something, which then interfaces with X.
> 

You may be able to hack some of the controls to support text selection
but you won't be able to do it for the general case. For example this
wouldn't work in Word. So I don't see this working. In fact it could
break assumption made by the application. In my opinion, the only way to
copy data from a Windows App to X is via control-c/Clipboard API. 

In Windows, to copy data you generally need to select the data (Under X
this would grab the PRIMARY selection) and then hit control-c (Under X
this would grab the CLIPBOARD selection). 

In think we should always be grabbing both PRIMARY and CLIPBOARD and
releasing them when we loose either (ClearAllSelections=1). This seemed
to be the least confusing for many users as well. 

I'm in the process of finishing a large clipboard patch for CodeWeavers
that should also address the dll separation issues. Hopefully I'll get
the patch together soon and post it to the list.


> So, I think x11drv/clipboard.c should be changed to basically eliminate
> references to PRIMARY, as without the ability to deal with middle clicks
> and grab-on-select, Wine has no business changing that selection.
> 
> Therefore my questions are:
> 
> 1) Should I try and hack up a patch to stop wine using PRIMARY?
> 2) What are the rules governing new wine specific APIs. I know the DLL
> Separation work is supposed to eliminate them, but there are no FAQs
> anywhere on it that I can see, could somebody explain this please?
> 
> thanks -mike
-- 
Ulrich Czekalla <ulrich.czekalla at utoronto.ca>
-- 
Ulrich Czekalla <ulrich.czekalla at utoronto.ca>