Re: [Qemu-devel] [PATCH] sdl: Do not disable screensaver by default

[Anthony Liguori <anthony@codemonkey.ws>]

On 05/24/2010 04:40 PM, Michael Tokarev wrote:
> 23.05.2010 12:29, Jan Kiszka wrote:
>> From: Jan Kiszka<jan.kiszka@siemens.com>
>>
>> Unless we are running in full-screen mode, QEMU's SDL window should not
>> disable the host's screensaver. The user can still change this behaviour
>> by setting the environment variable SDL_VIDEO_ALLOW_SCREENSAVER as
>> desired.
>>
>> Signed-off-by: Jan Kiszka<jan.kiszka@siemens.com>
>> ---
>>
>> Cool, thanks for digging out SDL_VIDEO_ALLOW_SCREENSAVER. I came across
>> by this issue as well but I was too lazy to analyze to reason. This
>> patch solves it for me.
>>
>>   sdl.c |    4 ++++
>>   1 files changed, 4 insertions(+), 0 deletions(-)
>>
>> diff --git a/sdl.c b/sdl.c
>> index 16a48e9..3bdd518 100644
>> --- a/sdl.c
>> +++ b/sdl.c
>> @@ -855,6 +855,10 @@ void sdl_display_init(DisplayState *ds, int 
>> full_screen, int no_frame)
>>       if (no_frame)
>>           gui_noframe = 1;
>>
>> +    if (!full_screen) {
>> +        setenv("SDL_VIDEO_ALLOW_SCREENSAVER", "1", 0);
>> +    }
>> +
>
> I think it's conceptually wrong.
>
> It's trivial to toggle full-screen mode by hitting Ctrl+Alt+F.

I don't think it's worth jumping through hoops to conditionally 
disable/enable screensaver.

More sophisticated screen saver behavior should be implemented in 
upstream SDL.

Regards,

Anthony Liguori

> Following this logic, on each toggle we should toggle the
> environment variable (which wont work).  Or else the next bug
> report to be filed is that screen saver isn't re-enabled when
> switching from fullscreen to window and it isn't re-disabled
> when switching to fullscreen.
>
> How about not poking at screensaver by default unconditionally?
> To me it sound more correct.  I.e., the above setenv(), but
> without the if part...
>
> Thanks!
>
> /mjt