Please HELP, info required about 'DIB_Status_GdiMod' and 'DIB_Status_AppMod'

[Marinescu-Ghetau Iulian]

Hi there,

Thanks alot for all the information, it helped me a great deal in 
understanding the problem and trying to solve it!
I would like to ask you one more thing: if its not too much trouble for you, 
could you have a look over the few lines i wrote at 
"http://bugs.winehq.org/show_bug.cgi?id=3902#c4" and tell me what you think 
? I found a way to fix the Bug and improve general bitmaps performance and 
wanted to know if it could work, before i start coding !

Iulian


>From: Robert Shearman <rob at codeweavers.com>
>To: Marinescu-Ghetau Iulian <giulian2003 at hotmail.com>
>CC: wine-devel at winehq.org
>Subject: Re: Please HELP,	info required about 'DIB_Status_GdiMod' and 
>'DIB_Status_AppMod'
>Date: Tue, 29 Nov 2005 11:25:23 -0600
>
>Marinescu-Ghetau Iulian wrote:
>
>>Hello,
>>
>>Could anyone give me some more info on  X11DRV_CoerceDIBSection function 
>>and the logic behind using 'DIB_Status_GdiMod' and 'DIB_Status_AppMod' 
>>stats? I am trying to repair a bug (3902) that has to do with application 
>>waiting exccessivly on some locks and i am kind of lost ;( Any help would 
>>be greatly appreciated!
>
>
>That code is designed to keep DIBs sync'ed between applications and the X 
>server. When the application does a Win32 GDI call then the state of the 
>DIB gets set to DIB_Status_GdiMod and the memory that backs the DIB is set 
>to no-access so that a page fault occurs if the application tries to read 
>it. A handler detects this and downloads the DIB from the X server and sets 
>the state to DIB_Status_None. In this state the DIB memory is set to 
>read-only, so that a page fault occurs if the application tries to write 
>it. The same handler also detects this and consequentially sets the DIB 
>state to DIB_Status_AppMod and allows full access to the DIB memory.
>
>If this doesn't answer help with your bug then you'll have to be more 
>specific.
>
>--
>Rob Shearman
>