[PATCH] winex11: Resize the screen when changing CRTC modes.

[Zebediah Figura]

Based on a patch by Gabriel Corona.

According to the RandR spec for RRSetCrtcConfig:

"The entire area of the CRTC must fit within the screen size, else a Match
error results. As an example, rotating the screen so that a single CRTC fills
the entire screen before and after may necessitate disabling the CRTC,
resizing the screen, then re-enabling the CRTC at the new configuration to
avoid an invalid intermediate configuration."

This patch involves resizing the screen also when shrinking a CRTC, not just
when expanding it past the current screen size. This is partially because we
have no way to reliably determine the current display width (DisplayWidth() is
never updated past opening the connection, and RandR exposes no way to
retrieve the screen dimensions), and partially because it's probably what the
user wants anyway (e.g. it's what the `xrandr` configuration app does when the
screen size is not expliticly specified).

This patch fixes TestBot failures on the Debian machines for ddraw, d3d8, and
d3d9 device tests.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=33290
Signed-off-by: Zebediah Figura <z.figura12 at gmail.com>
---
 dlls/winex11.drv/xrandr.c | 55 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/dlls/winex11.drv/xrandr.c b/dlls/winex11.drv/xrandr.c
index 2fee851ad7..9f63310291 100644
--- a/dlls/winex11.drv/xrandr.c
+++ b/dlls/winex11.drv/xrandr.c
@@ -58,6 +58,7 @@ MAKE_FUNCPTR(XRRGetCrtcInfo)
 MAKE_FUNCPTR(XRRGetOutputInfo)
 MAKE_FUNCPTR(XRRGetScreenResources)
 MAKE_FUNCPTR(XRRSetCrtcConfig)
+MAKE_FUNCPTR(XRRSetScreenSize)
 static typeof(XRRGetScreenResources) *pXRRGetScreenResourcesCurrent;
 static RRMode *xrandr12_modes;
 static int primary_crtc;
@@ -102,6 +103,7 @@ static int load_xrandr(void)
         LOAD_FUNCPTR(XRRGetOutputInfo)
         LOAD_FUNCPTR(XRRGetScreenResources)
         LOAD_FUNCPTR(XRRSetCrtcConfig)
+        LOAD_FUNCPTR(XRRSetScreenSize)
         r = 2;
 #endif
 #undef LOAD_FUNCPTR
@@ -320,8 +322,30 @@ static int xrandr12_get_current_mode(void)
     return ret;
 }
 
+static void get_screen_size( XRRScreenResources *resources, unsigned int *width, unsigned int *height )
+{
+    XRRCrtcInfo *crtc_info;
+    int i;
+    *width = *height = 0;
+
+    for (i = 0; i < resources->ncrtc; ++i)
+    {
+        if (!(crtc_info = pXRRGetCrtcInfo( gdi_display, resources, resources->crtcs[i] )))
+            continue;
+
+        if (crtc_info->mode != None)
+        {
+            *width = max(*width, crtc_info->x + crtc_info->width);
+            *height = max(*height, crtc_info->y + crtc_info->height);
+        }
+
+        pXRRFreeCrtcInfo( crtc_info );
+    }
+}
+
 static LONG xrandr12_set_current_mode( int mode )
 {
+    unsigned int screen_width, screen_height;
     Status status = RRSetConfigFailed;
     XRRScreenResources *resources;
     XRRCrtcInfo *crtc_info;
@@ -345,10 +369,41 @@ static LONG xrandr12_set_current_mode( int mode )
     TRACE("CRTC %d: mode %#lx, %ux%u+%d+%d.\n", primary_crtc, crtc_info->mode,
           crtc_info->width, crtc_info->height, crtc_info->x, crtc_info->y);
 
+    /* According to the RandR spec, the entire CRTC must fit inside the screen.
+     * Since we use the union of all enabled CRTCs to determine the necessary
+     * screen size, this might involve shrinking the screen, so we must disable
+     * the CRTC in question first. */
+
+    XGrabServer( gdi_display );
+
+    status = pXRRSetCrtcConfig( gdi_display, resources, resources->crtcs[primary_crtc],
+                                CurrentTime, crtc_info->x, crtc_info->y, None,
+                                crtc_info->rotation, NULL, 0 );
+    if (status != RRSetConfigSuccess)
+    {
+        XUngrabServer( gdi_display );
+        ERR("Failed to disable CRTC.\n");
+        pXRRFreeCrtcInfo( crtc_info );
+        pXRRFreeScreenResources( resources );
+        return DISP_CHANGE_FAILED;
+    }
+
+    get_screen_size( resources, &screen_width, &screen_height );
+    screen_width = max( screen_width, crtc_info->x + dd_modes[mode].width );
+    screen_height = max( screen_height, crtc_info->y + dd_modes[mode].height );
+
+    pXRRSetScreenSize( gdi_display, root_window, screen_width, screen_height,
+            screen_width * DisplayWidthMM( gdi_display, default_visual.screen )
+                         / DisplayWidth( gdi_display, default_visual.screen ),
+            screen_height * DisplayHeightMM( gdi_display, default_visual.screen )
+                         / DisplayHeight( gdi_display, default_visual.screen ));
+
     status = pXRRSetCrtcConfig( gdi_display, resources, resources->crtcs[primary_crtc],
                                 CurrentTime, crtc_info->x, crtc_info->y, xrandr12_modes[mode],
                                 crtc_info->rotation, crtc_info->outputs, crtc_info->noutput );
 
+    XUngrabServer( gdi_display );
+
     pXRRFreeCrtcInfo( crtc_info );
     pXRRFreeScreenResources( resources );
 
-- 
2.21.0