[PATCH 0/1] MR303: win32u: Don't report cloned monitors in EnumDisplayMonitors().

[Arek Hiler (＠ivyl)]

Based on:
ca39b1c22dfa ("user32: Don't report mirrored slave monitors in EnumDisplayMonitors.")
2affb854e524 ("user32: Change slave to a more neutral word.")

Which seems to got lost during:
318673405c62 ("win32u: Move NtUserEnumDisplayMonitors implementation from user32.")

Fixes regression with Elite Dangerous launcher freezing when cloned
displays are present.

Signed-off-by: Arkadiusz Hiler

CC: @zhiyi @jacek

[PATCH 1/1] win32u: Don't report cloned monitors in EnumDisplayMonitors().

[Arkadiusz Hiler]

From: Arkadiusz Hiler

Based on:
ca39b1c22dfa ("user32: Don't report mirrored slave monitors in EnumDisplayMonitors.")
2affb854e524 ("user32: Change slave to a more neutral word.")

Which seems to got lost during:
318673405c62 ("win32u: Move NtUserEnumDisplayMonitors implementation from user32.")

Fixes regression with Elite Dangerous launcher freezing when cloned
displays are present.

Signed-off-by: Arkadiusz Hiler 
---
 dlls/win32u/sysparams.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/dlls/win32u/sysparams.c b/dlls/win32u/sysparams.c
index a8c1d977c7d..3a83452cf16 100644
--- a/dlls/win32u/sysparams.c
+++ b/dlls/win32u/sysparams.c
@@ -1249,9 +1249,10 @@ static BOOL update_display_cache_from_registry(void)
     DWORD adapter_id, monitor_id, monitor_count = 0, size;
     KEY_BASIC_INFORMATION key;
     struct adapter *adapter;
-    struct monitor *monitor;
+    struct monitor *monitor, *monitor2;
     HANDLE mutex = NULL;
     NTSTATUS status;
+    BOOL is_cloned;
     BOOL ret;

/* If user driver did initialize the registry, then exit */
@@ -1295,6 +1296,19 @@ static BOOL update_display_cache_from_registry(void)
                 break;
             }

+            is_cloned = FALSE;
+            LIST_FOR_EACH_ENTRY(monitor2, &monitors, struct monitor, entry)
+            {
+                if (EqualRect(&monitor2->rc_monitor, &monitor->rc_monitor))
+                {
+                    is_cloned = TRUE;
+                    break;
+                }
+            }
+
+            if (is_cloned)
+                continue;
+
             monitor->handle = UlongToHandle( ++monitor_count );
             list_add_tail( &monitors, &monitor->entry );
         }

[Zhiyi Zhang (＠zhiyi)]

Zhiyi Zhang (@zhiyi) commented about dlls/win32u/sysparams.c:
>              break;
>          }
>
> -
>        is_cloned = FALSE;
> -
>        LIST_FOR_EACH_ENTRY(monitor2, &monitors, struct monitor, entry)
> -
>        {
> -
>            if (EqualRect(&monitor2->rc_monitor, &monitor->rc_monitor))
> -
>            {
> -
>                is_cloned = TRUE;
> -
>                break;
> -
>            }
> -
>        }
> -
> -
>        if (is_cloned)
> -
>            continue;

If the monitor to be added is the last monitor and is a cloned replica, this will leak the monitor pointer.