[PATCH 3/3] winex11.drv: Handle XRandR not reporting any providers.

[Zhiyi Zhang]

Some XRandR implementations, e.g., the QXL driver used on Debian 10
TestBots, don't report any providers. In this case, we can still
search in XRandR screen resources to get adapters.

Signed-off-by: Zhiyi Zhang <zzhang(a)codeweavers.com>
---
 dlls/winex11.drv/xrandr.c | 45 ++++++++++++++++++++++++++++++++-------
 1 file changed, 37 insertions(+), 8 deletions(-)

diff --git a/dlls/winex11.drv/xrandr.c b/dlls/winex11.drv/xrandr.c
index 2a1c7ce594..6bb2b18ce7 100644
--- a/dlls/winex11.drv/xrandr.c
+++ b/dlls/winex11.drv/xrandr.c
@@ -662,6 +662,7 @@ static BOOL is_crtc_primary( RECT primary, const XRRCrtcInfo *crtc )
 
 static BOOL xrandr14_get_gpus( struct x11drv_gpu **new_gpus, int *count )
 {
+    static const WCHAR wine_adapterW[] = {'W','i','n','e',' ','A','d','a','p','t','e','r',0};
     struct x11drv_gpu *gpus = NULL;
     XRRScreenResources *screen_resources = NULL;
     XRRProviderResources *provider_resources = NULL;
@@ -680,10 +681,22 @@ static BOOL xrandr14_get_gpus( struct x11drv_gpu **new_gpus, int *count )
     if (!provider_resources)
         goto done;
 
-    gpus = heap_calloc( provider_resources->nproviders, sizeof(*gpus) );
+    gpus = heap_calloc( provider_resources->nproviders ? provider_resources->nproviders : 1, sizeof(*gpus) );
     if (!gpus)
         goto done;
 
+    /* Some XRandR implementations don't support providers.
+     * In this case, report a fake one to try searching adapters in screen resources */
+    if (!provider_resources->nproviders)
+    {
+        WARN("XRandR implementation doesn't report any providers, faking one.\n");
+        lstrcpyW( gpus[0].name, wine_adapterW );
+        *new_gpus = gpus;
+        *count = 1;
+        ret = TRUE;
+        goto done;
+    }
+
     primary_rect = get_primary_rect( screen_resources );
     for (i = 0; i < provider_resources->nproviders; ++i)
     {
@@ -751,6 +764,8 @@ static BOOL xrandr14_get_adapters( ULONG_PTR gpu_id, struct x11drv_adapter **new
     XRRProviderInfo *provider_info = NULL;
     XRRCrtcInfo *enum_crtc_info, *crtc_info = NULL;
     XRROutputInfo *output_info = NULL;
+    RROutput *outputs;
+    INT crtc_count, output_count;
     INT primary_adapter = 0;
     INT adapter_count = 0;
     BOOL mirrored, detached;
@@ -762,19 +777,33 @@ static BOOL xrandr14_get_adapters( ULONG_PTR gpu_id, struct x11drv_adapter **new
     if (!screen_resources)
         goto done;
 
-    provider_info = pXRRGetProviderInfo( gdi_display, screen_resources, gpu_id );
-    if (!provider_info)
-        goto done;
+    if (gpu_id)
+    {
+        provider_info = pXRRGetProviderInfo( gdi_display, screen_resources, gpu_id );
+        if (!provider_info)
+            goto done;
+
+        crtc_count = provider_info->ncrtcs;
+        output_count = provider_info->noutputs;
+        outputs = provider_info->outputs;
+    }
+    /* Fake provider id, search adapters in screen resources */
+    else
+    {
+        crtc_count = screen_resources->ncrtc;
+        output_count = screen_resources->noutput;
+        outputs = screen_resources->outputs;
+    }
 
     /* Actual adapter count could be less */
-    adapters = heap_calloc( provider_info->ncrtcs, sizeof(*adapters) );
+    adapters = heap_calloc( crtc_count, sizeof(*adapters) );
     if (!adapters)
         goto done;
 
     primary_rect = get_primary_rect( screen_resources );
-    for (i = 0; i < provider_info->noutputs; ++i)
+    for (i = 0; i < output_count; ++i)
     {
-        output_info = pXRRGetOutputInfo( gdi_display, screen_resources, provider_info->outputs[i] );
+        output_info = pXRRGetOutputInfo( gdi_display, screen_resources, outputs[i] );
         if (!output_info)
             goto done;
 
@@ -830,7 +859,7 @@ static BOOL xrandr14_get_adapters( ULONG_PTR gpu_id, struct x11drv_adapter **new
         {
             /* Use RROutput as adapter id. The reason of not using RRCrtc is that we need to detect inactive but
              * attached monitors */
-            adapters[adapter_count].id = provider_info->outputs[i];
+            adapters[adapter_count].id = outputs[i];
             if (!detached)
                 adapters[adapter_count].state_flags |= DISPLAY_DEVICE_ATTACHED_TO_DESKTOP;
             if (is_crtc_primary( primary_rect, crtc_info ))
-- 
2.20.1