[PATCH 3/6] user32: Handle NULL device and mode parameters in ChangeDisplaySettingsExW().

[Zhiyi Zhang]

NULL device and mode means to restore all devices to their registry settings.
Since all user graphics drivers only support the primary adapter now,
it's fine to restore only the primary adapter.

Signed-off-by: Zhiyi Zhang <zzhang at codeweavers.com>
---
 dlls/user32/sysparams.c     |  3 +++
 dlls/winemac.drv/display.c  | 35 +++++++++++++++++++++++++++++++++++
 dlls/winex11.drv/settings.c | 36 ++++++++++++++++++++++++++++++++++++
 dlls/winex11.drv/x11drv.h   |  1 +
 4 files changed, 75 insertions(+)

diff --git a/dlls/user32/sysparams.c b/dlls/user32/sysparams.c
index c5c98a7ea1..a60e4a2dbd 100644
--- a/dlls/user32/sysparams.c
+++ b/dlls/user32/sysparams.c
@@ -3300,6 +3300,9 @@ LONG WINAPI ChangeDisplaySettingsExW( LPCWSTR devname, LPDEVMODEW devmode, HWND
     TRACE("%s %p %p %#x %p\n", debugstr_w(devname), devmode, hwnd, flags, lparam);
     TRACE("flags=%s\n", _CDS_flags(flags));
 
+    if (!devname && !devmode)
+        return USER_Driver->pChangeDisplaySettingsEx(NULL, NULL, hwnd, flags, lparam);
+
     if (!devname && devmode)
     {
         if (!get_primary_adapter(primary_adapter))
diff --git a/dlls/winemac.drv/display.c b/dlls/winemac.drv/display.c
index 4c610c4573..0a05753b8e 100644
--- a/dlls/winemac.drv/display.c
+++ b/dlls/winemac.drv/display.c
@@ -745,6 +745,23 @@ void check_retina_status(void)
     }
 }
 
+static BOOL get_primary_adapter(WCHAR *name)
+{
+    DISPLAY_DEVICEW dd;
+    DWORD i;
+
+    dd.cb = sizeof(dd);
+    for (i = 0; EnumDisplayDevicesW(NULL, i, &dd, 0); ++i)
+    {
+        if (dd.StateFlags & DISPLAY_DEVICE_PRIMARY_DEVICE)
+        {
+            lstrcpyW(name, dd.DeviceName);
+            return TRUE;
+        }
+    }
+
+    return FALSE;
+}
 
 /***********************************************************************
  *              ChangeDisplaySettingsEx  (MACDRV.@)
@@ -753,7 +770,9 @@ void check_retina_status(void)
 LONG CDECL macdrv_ChangeDisplaySettingsEx(LPCWSTR devname, LPDEVMODEW devmode,
                                           HWND hwnd, DWORD flags, LPVOID lpvoid)
 {
+    WCHAR primary_adapter[CCHDEVICENAME];
     LONG ret = DISP_CHANGE_BADMODE;
+    DEVMODEW default_mode;
     int bpp;
     struct macdrv_display *displays;
     int num_displays;
@@ -768,6 +787,22 @@ LONG CDECL macdrv_ChangeDisplaySettingsEx(LPCWSTR devname, LPDEVMODEW devmode,
 
     init_original_display_mode();
 
+    if (!get_primary_adapter(primary_adapter))
+        return DISP_CHANGE_FAILED;
+
+    if (!devname && !devmode)
+    {
+        default_mode.dmSize = sizeof(default_mode);
+        if (!EnumDisplaySettingsExW(primary_adapter, ENUM_REGISTRY_SETTINGS, &default_mode, 0))
+        {
+            ERR("Default mode not found for %s!\n", wine_dbgstr_w(primary_adapter));
+            return DISP_CHANGE_BADMODE;
+        }
+
+        devname = primary_adapter;
+        devmode = &default_mode;
+    }
+
     if (macdrv_get_displays(&displays, &num_displays))
         return DISP_CHANGE_FAILED;
 
diff --git a/dlls/winex11.drv/settings.c b/dlls/winex11.drv/settings.c
index 24644db620..3e7a5960f0 100644
--- a/dlls/winex11.drv/settings.c
+++ b/dlls/winex11.drv/settings.c
@@ -252,6 +252,24 @@ static BOOL write_registry_settings(const DEVMODEW *dm)
     return ret;
 }
 
+BOOL get_primary_adapter(WCHAR *name)
+{
+    DISPLAY_DEVICEW dd;
+    DWORD i;
+
+    dd.cb = sizeof(dd);
+    for (i = 0; EnumDisplayDevicesW(NULL, i, &dd, 0); ++i)
+    {
+        if (dd.StateFlags & DISPLAY_DEVICE_PRIMARY_DEVICE)
+        {
+            lstrcpyW(name, dd.DeviceName);
+            return TRUE;
+        }
+    }
+
+    return FALSE;
+}
+
 /***********************************************************************
  *		EnumDisplaySettingsEx  (X11DRV.@)
  *
@@ -318,9 +336,27 @@ BOOL CDECL X11DRV_EnumDisplaySettingsEx( LPCWSTR name, DWORD n, LPDEVMODEW devmo
 LONG CDECL X11DRV_ChangeDisplaySettingsEx( LPCWSTR devname, LPDEVMODEW devmode,
                                            HWND hwnd, DWORD flags, LPVOID lpvoid )
 {
+    WCHAR primary_adapter[CCHDEVICENAME];
     char bpp_buffer[16], freq_buffer[18];
+    DEVMODEW default_mode;
     DWORD i;
 
+    if (!get_primary_adapter(primary_adapter))
+        return DISP_CHANGE_FAILED;
+
+    if (!devname && !devmode)
+    {
+        default_mode.dmSize = sizeof(default_mode);
+        if (!EnumDisplaySettingsExW(primary_adapter, ENUM_REGISTRY_SETTINGS, &default_mode, 0))
+        {
+            ERR("Default mode not found for %s!\n", wine_dbgstr_w(primary_adapter));
+            return DISP_CHANGE_BADMODE;
+        }
+
+        devname = primary_adapter;
+        devmode = &default_mode;
+    }
+
     for (i = 0; i < dd_mode_count; i++)
     {
         if (devmode->dmFields & DM_BITSPERPEL)
diff --git a/dlls/winex11.drv/x11drv.h b/dlls/winex11.drv/x11drv.h
index 98cab8947b..c99985e7e6 100644
--- a/dlls/winex11.drv/x11drv.h
+++ b/dlls/winex11.drv/x11drv.h
@@ -661,6 +661,7 @@ extern void X11DRV_resize_desktop(unsigned int width, unsigned int height) DECLS
 extern BOOL is_virtual_desktop(void) DECLSPEC_HIDDEN;
 extern BOOL is_desktop_fullscreen(void) DECLSPEC_HIDDEN;
 extern BOOL create_desktop_win_data( Window win ) DECLSPEC_HIDDEN;
+extern BOOL get_primary_adapter(WCHAR *) DECLSPEC_HIDDEN;
 extern void X11DRV_Settings_AddDepthModes(void) DECLSPEC_HIDDEN;
 extern void X11DRV_Settings_AddOneMode(unsigned int width, unsigned int height, unsigned int bpp, unsigned int freq) DECLSPEC_HIDDEN;
 unsigned int X11DRV_Settings_GetModeCount(void) DECLSPEC_HIDDEN;
-- 
2.20.1