[PATCH 5/5] win32u: Only read/write valid mode fields from/to the registry.

[Rémi Bernon]

From: R��mi Bernon

And make dmDisplayFixedOutput / DM_DISPLAYFIXEDOUTPUT optional.
---
 dlls/win32u/sysparams.c | 31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/dlls/win32u/sysparams.c b/dlls/win32u/sysparams.c
index edf094cd1e7..94c827304c3 100644
--- a/dlls/win32u/sysparams.c
+++ b/dlls/win32u/sysparams.c
@@ -433,12 +433,20 @@ static BOOL write_adapter_mode( HKEY adapter_key, DWORD index, const DEVMODEW *m
     BOOL ret;

sprintf( buffer, "Modes\%08X", index );
+    reg_delete_tree( adapter_key, bufferW, asciiz_to_unicode( bufferW, buffer ) - sizeof(WCHAR) );
     if (!(hkey = reg_create_key( adapter_key, bufferW, asciiz_to_unicode( bufferW, buffer ) - sizeof(WCHAR),
                                  REG_OPTION_VOLATILE, NULL )))
         return FALSE;

-#define set_mode_field( name, field, flag ) \
-    if (!(ret = set_reg_value( hkey, (name), REG_DWORD, &mode->field, sizeof(mode->field) ))) goto done;
+
+#define set_mode_field( name, field, flag )                                                      \
+    do                                                                                           \
+    {                                                                                            \
+        if (!(mode->dmFields & (flag))) ret = (index == ENUM_REGISTRY_SETTINGS);                 \
+        else ret = set_reg_value( hkey, (name), REG_DWORD, &mode->field,                         \
+                                  sizeof(mode->field) );                                         \
+        if (!ret) goto done;                                                                     \
+    } while (0)

set_mode_field( bits_per_pelW, dmBitsPerPel, DM_BITSPERPEL );
     set_mode_field( x_resolutionW, dmPelsWidth, DM_PELSWIDTH );
@@ -446,7 +454,7 @@ static BOOL write_adapter_mode( HKEY adapter_key, DWORD index, const DEVMODEW *m
     set_mode_field( v_refreshW, dmDisplayFrequency, DM_DISPLAYFREQUENCY );
     set_mode_field( flagsW, dmDisplayFlags, DM_DISPLAYFLAGS );
     set_mode_field( orientationW, dmDisplayOrientation, DM_DISPLAYORIENTATION );
-    set_mode_field( fixed_outputW, dmDisplayFixedOutput, DM_DISPLAYFIXEDOUTPUT );
+    if (mode->dmFields & DM_DISPLAYFIXEDOUTPUT) set_mode_field( fixed_outputW, dmDisplayFixedOutput, DM_DISPLAYFIXEDOUTPUT );
     if (index == ENUM_CURRENT_SETTINGS || index == ENUM_REGISTRY_SETTINGS)
     {
         set_mode_field( x_panningW, dmPosition.x, DM_POSITION );
@@ -467,7 +475,6 @@ static BOOL read_adapter_mode( HKEY adapter_key, DWORD index, DEVMODEW *mode )
     WCHAR bufferW[MAX_PATH];
     char buffer[MAX_PATH];
     HKEY hkey;
-    BOOL ret;

sprintf( buffer, "Modes\%08X", index );
     if (!(hkey = reg_open_key( adapter_key, bufferW, asciiz_to_unicode( bufferW, buffer ) - sizeof(WCHAR) )))
@@ -476,11 +483,12 @@ static BOOL read_adapter_mode( HKEY adapter_key, DWORD index, DEVMODEW *mode )
 #define query_mode_field( name, field, flag )                                                      \
     do                                                                                             \
     {                                                                                              \
-        ret = query_reg_value( hkey, (name), value, sizeof(value_buf) ) &&                         \
-              value->Type == REG_DWORD;                                                            \
-        if (!ret) goto done;                                                                       \
-        mode->field = *(const DWORD *)value->Data;                                                 \
-        mode->dmFields |= (flag);                                                                  \
+        if (query_reg_value( hkey, (name), value, sizeof(value_buf) ) &&                           \
+            value->Type == REG_DWORD)                                                              \
+        {                                                                                          \
+            mode->field = *(const DWORD *)value->Data;                                             \
+            mode->dmFields |= (flag);                                                              \
+        }                                                                                          \
     } while (0)

query_mode_field( bits_per_pelW, dmBitsPerPel, DM_BITSPERPEL );
@@ -488,17 +496,16 @@ static BOOL read_adapter_mode( HKEY adapter_key, DWORD index, DEVMODEW *mode )
     query_mode_field( y_resolutionW, dmPelsHeight, DM_PELSHEIGHT );
     query_mode_field( v_refreshW, dmDisplayFrequency, DM_DISPLAYFREQUENCY );
     query_mode_field( flagsW, dmDisplayFlags, DM_DISPLAYFLAGS );
+    query_mode_field( orientationW, dmDisplayOrientation, DM_DISPLAYORIENTATION );
+    query_mode_field( fixed_outputW, dmDisplayFixedOutput, DM_DISPLAYFIXEDOUTPUT );
     if (index == ENUM_CURRENT_SETTINGS || index == ENUM_REGISTRY_SETTINGS)
     {
         query_mode_field( x_panningW, dmPosition.x, DM_POSITION );
         query_mode_field( y_panningW, dmPosition.y, DM_POSITION );
     }
-    query_mode_field( orientationW, dmDisplayOrientation, DM_DISPLAYORIENTATION );
-    query_mode_field( fixed_outputW, dmDisplayFixedOutput, 0 );

#undef query_mode_field

-done:
     NtClose( hkey );
     return TRUE;
 }