[Qemu-devel] [PATCH] don't die if switching to fullscreen mode fails
hi,
the attached patch fixes some glitches when switching to fullscreen mode
using ctrl+alt+f or when booting using -full-screen.
up to now the VM simply dies if one of the following situations occur:
* user switches from windowed to fullscreen mode using a resolution
which is too high (meaning higher than the maximum resolution of the
display)
* guest boots in fullscreen mode using a resolution which is too high
* guest is in fullscreen mode and the user switches to a resolution
which is too high
IMO this is not what the normal user would expect.
This patch changes the behaviour as follows:
* deny switching to fullscreen mode if the resolution is too high and
print a message to the console
* use windowed mode as fallback option if we are already in
fullscreen mode and the new resolution is too high and print a message
to the console
cheers,
Andi
--- qemu/sdl.c 2007-11-17 18:14:38.0 +0100
+++ qemu/sdl.c 2008-02-26 13:32:29.0 +0100
@@ -56,46 +56,60 @@ static void sdl_update(DisplayState *ds,
SDL_UpdateRect(screen, x, y, w, h);
}
-static void sdl_resize(DisplayState *ds, int w, int h)
+static int sdl_resize2(DisplayState *ds, int w, int h, int full_screen, int no_frame)
{
+SDL_Surface *screen_tmp;
int flags;
-//printf(resizing to %d %d\n, w, h);
+//printf(trying to resize from w=%d h=%d %s to w=%d h=%d %s\n, width, height, gui_fullscreen ? fullscreen : windowed, w, h, full_screen ? fullscreen : windowed);
flags = SDL_HWSURFACE|SDL_ASYNCBLIT|SDL_HWACCEL;
-if (gui_fullscreen)
+if (full_screen)
flags |= SDL_FULLSCREEN;
-if (gui_noframe)
+if (no_frame)
flags |= SDL_NOFRAME;
-width = w;
-height = h;
-
- again:
-screen = SDL_SetVideoMode(w, h, 0, flags);
-if (!screen) {
-fprintf(stderr, Could not open SDL display\n);
-exit(1);
-}
-if (!screen-pixels (flags SDL_HWSURFACE) (flags SDL_FULLSCREEN)) {
-flags = ~SDL_HWSURFACE;
-goto again;
+if (!(screen_tmp = SDL_SetVideoMode(w, h, 0, flags))) {
+//fprintf(stderr, Could not open SDL display (try #1)\n);
+return -1;
+} else if (!screen_tmp-pixels (flags SDL_HWSURFACE) (flags SDL_FULLSCREEN)) {
+screen_tmp = SDL_SetVideoMode(w, h, 0, flags ~SDL_HWSURFACE);
}
-if (!screen-pixels) {
-fprintf(stderr, Could not open SDL display\n);
-exit(1);
-}
-ds-data = screen-pixels;
-ds-linesize = screen-pitch;
-ds-depth = screen-format-BitsPerPixel;
-if (screen-format-Bshift screen-format-Rshift) {
-ds-bgr = 1;
+if (!screen_tmp || !screen_tmp-pixels) {
+//fprintf(stderr, Could not open SDL display (try #2)\n);
+return -1;
} else {
-ds-bgr = 0;
+screen = screen_tmp;
+gui_fullscreen = full_screen;
+gui_noframe = no_frame;
+
+ds-data = screen-pixels;
+ds-linesize = screen-pitch;
+ds-depth = screen-format-BitsPerPixel;
+if (screen-format-Bshift screen-format-Rshift) {
+ds-bgr = 1;
+} else {
+ds-bgr = 0;
+}
+ds-width = width = w;
+ds-height = height = h;
+}
+}
+
+static void sdl_resize(DisplayState *ds, int w, int h)
+{
+if (sdl_resize2(ds, w, h, gui_fullscreen, gui_noframe) == -1) {
+fprintf(stderr, Could not resize display to %d x %d (%s)\n,
+ w, h, gui_fullscreen ? fullscreen : windowed);
+
+/* if we are in fullscreen mode use windowed mode as fallback */
+if (!gui_fullscreen || sdl_resize2(ds, w, h, 0, gui_noframe) == -1) {
+exit(1);
+} else {
+fprintf(stderr, Using windowed mode as fallback\n);
+}
}
-ds-width = w;
-ds-height = h;
}
/* generic keyboard conversion */
@@ -330,17 +344,21 @@ static void sdl_send_mouse_event(int dz)
static void toggle_full_screen(DisplayState *ds)
{
-gui_fullscreen = !gui_fullscreen;
-sdl_resize(ds, screen-w, screen-h);
-if (gui_fullscreen) {
-gui_saved_grab = gui_grab;
-sdl_grab_start();
-} else {
-if (!gui_saved_grab)
-sdl_grab_end();
+if (sdl_resize2(ds, screen-w, screen-h, !gui_fullscreen, gui_noframe) != -1) {
+if (gui_fullscreen) {
+gui_saved_grab = gui_grab;
+sdl_grab_start();
+} else {
+if (!gui_saved_grab)
+sdl_grab_end();
+}
+vga_hw_invalidate();
+vga_hw_update();
+}
+else {
+fprintf(stderr, Could not switch to %s mode\n,
+ !gui_fullscreen ? fullscreen : windowed);
}
-vga_hw_invalidate();
-vga_hw_update();
}
static void sdl_refresh(DisplayState *ds)
@@ -603,14 +621,14 @@ void sdl_display_init(DisplayState *ds,
exit(1);
}
-if (no_frame)
-gui_noframe = 1;
-
flags = SDL_INIT_VIDEO | SDL_INIT_NOPARACHUTE;
if
Re: [Qemu-devel] [PATCH] don't die if switching to fullscreen mode fails
Hi, On Tue, 26 Feb 2008, Andreas Winkelbauer wrote: the attached patch fixes some glitches when switching to fullscreen mode using ctrl+alt+f or when booting using -full-screen. Wow. This patch is messy, if I may say so. There must be a more elegant way to do this, especially given the fact that you remove atexit(sdl_cleanup)s without explanation. Ciao, Dscho
Re: [Qemu-devel] [PATCH] don't die if switching to fullscreen mode fails
Am 26.02.2008 um 13:48 schrieb Andreas Winkelbauer: This patch changes the behaviour as follows: * deny switching to fullscreen mode if the resolution is too high and print a message to the console Very good idea. * use windowed mode as fallback option if we are already in fullscreen mode and the new resolution is too high and print a message to the console Do you end up with a window bigger than the screen, then? Is there a chance the user can escape from this situation, i.e. reach all parts of the virtual screen to find the switch for setting the resolution? Another option would be to simply display an Out of range error across the screen, like a real monitor would do. Usually, operations systems feature a protection against setting a resolution higher than supported by hardware already (set back to a lower reolution after some delay). Markus - - - - - - - - - - - - - - - - - - - Dipl. Ing. Markus Hitter http://www.jump-ing.de/
Re: [Qemu-devel] [PATCH] don't die if switching to fullscreen mode fails
hi, Wow. This patch is messy, if I may say so. There must be a more elegant way to do this, especially given the fact that you remove atexit(sdl_cleanup)s without explanation. well, the diff output is messy, because I added sdl_resize2() above sdl_resize() to avoid adding a forward declaration. the patch itself might be messy as well, but that depends on your point of view. I don't think it is too messy. I did it that way because I wanted the patch to be as less invasively as possible. I did not change any existing function prototypes and all the changes are restricted to one source file. just as an example: changing the function prototype of sdl_resize() would lead to much more changes at other places as well to make things consistent again. I don't think this would make the patch less messy. I didn't remove the atexit() call, it is just moved some lines upwards (look carefully) because now there is a check if the initial resize to 640x400 fails. If it fails we call exit() and that means the call to atexit() must be done before a possible call to exit(). However, I agree with you that there should exist another solution. Does qemu have access to the maximum resolution of the host display? cheers, Andi
Re: [Qemu-devel] [PATCH] don't die if switching to fullscreen mode fails
hi, use windowed mode as fallback option if we are already in fullscreen mode and the new resolution is too high and print a message to the console Do you end up with a window bigger than the screen, then? Is there a chance the user can escape from this situation, i.e. reach all parts of the virtual screen to find the switch for setting the resolution? yes, that's true, but it is no problem at all. First of all you can move the window around so it is possible to reach everything inside the window. in addition you can always use ctrl+alt+del under windows to shutdown. under X11 you can always escape using ctrl+alt+backspace. Another option would be to simply display an Out of range error across the screen, like a real monitor would do. Usually, operations systems feature a protection against setting a resolution higher than supported by hardware already (set back to a lower reolution after some delay). to make that working we would need to know the maximum resolution of the host display. does qemu store this information somewhere? but I think this would not work anyway because the guest os might (at least windows does) crash if qemu resizes the display to an other resolution than the requested one. so testing if the new resolution is too high and in case using a lower resolution would crash windows xp, I have tried that already. I've extensively tested this patch using windows as guest os and it works perfectly for me. Maybe somebody could test the patch using other guest os as well. cheers, Andi
