[BOOTDATA][NTUSER] Add UserIsIMMEnabled and use it (#4882)

This PR enables SRVINFO_IMM32 also for non-CJK. You can disable this flag by setting zero to the LoadIMM registry value if you're non-CJK.
CORE-11700

boot/bootdata/hivesft.inf

@@ -512,7 +512,7 @@ HKLM,"SOFTWARE\Microsoft\Windows NT\CurrentVersion\FontMapper",,0x00000012
 HKLM,"SOFTWARE\Microsoft\Windows NT\CurrentVersion\HotFix",,0x00000012
 HKLM,"SOFTWARE\Microsoft\Windows NT\CurrentVersion\IME Compatibility",,0x00000012
 
-HKLM,"SOFTWARE\Microsoft\Windows NT\CurrentVersion\IMM","LoadIMM",0x00010003,0
+HKLM,"SOFTWARE\Microsoft\Windows NT\CurrentVersion\IMM","LoadIMM",0x00010003,1
 HKLM,"SOFTWARE\Microsoft\Windows NT\CurrentVersion\IMM","LoadCTFIME",0x00010003,0
 
 ; DOS Device ports

win32ss/gdi/ntgdi/misc.h

@@ -54,6 +54,10 @@ BOOL
 NTAPI
 RegReadDWORD(HKEY hkey, PWSTR pwszValue, PDWORD pdwData);
 
+DWORD
+NTAPI
+RegGetSectionDWORD(LPCWSTR pszSection, LPWSTR pszValue, DWORD dwDefault);
+
 VOID FASTCALL
 SetLastNtError(
   NTSTATUS Status);

win32ss/user/ntuser/ime.c

@@ -562,7 +562,7 @@ DWORD FASTCALL UserBuildHimcList(PTHREADINFO pti, DWORD dwCount, HIMC *phList)
     }
     else
     {
-        for (pti = GetW32ThreadInfo()->ppi->ptiList; pti; pti = pti->ptiSibling)
+        for (pti = gptiCurrent->ppi->ptiList; pti; pti = pti->ptiSibling)
         {
             for (pIMC = pti->spDefaultImc; pIMC; pIMC = pIMC->pImcNext)
             {
@@ -716,7 +716,7 @@ NtUserBuildHimcList(DWORD dwThreadId, DWORD dwCount, HIMC *phList, LPDWORD pdwCo
 
     if (dwThreadId == 0)
     {
-        pti = GetW32ThreadInfo();
+        pti = gptiCurrent;
     }
     else if (dwThreadId == INVALID_THREAD_ID)
     {

win32ss/user/ntuser/metric.c

@@ -14,6 +14,26 @@ static BOOL Setup = FALSE;
 
 /* FUNCTIONS *****************************************************************/
 
+BOOL FASTCALL UserIsDBCSEnabled(VOID)
+{
+    return NLS_MB_CODE_PAGE_TAG;
+}
+
+BOOL FASTCALL UserIsIMMEnabled(VOID)
+{
+    static WCHAR s_szLoadIMM[] = L"LoadIMM";
+
+    if (NLS_MB_CODE_PAGE_TAG)
+        return TRUE;
+
+    return !!RegGetSectionDWORD(L"IMM", s_szLoadIMM, TRUE);
+}
+
+BOOL FASTCALL UserIsCiceroEnabled(VOID)
+{
+    return FALSE; /* FIXME: Cicero is not supported yet */
+}
+
 BOOL
 NTAPI
 InitMetrics(VOID)
@@ -169,12 +189,14 @@ InitMetrics(VOID)
     piSysMet[90] = 0;
 #endif
 
-    /*gpsi->dwSRVIFlags |= SRVINFO_CICERO_ENABLED;*/ /* Cicero is not supported yet */
+    if (UserIsDBCSEnabled())
+        gpsi->dwSRVIFlags |= SRVINFO_DBCSENABLED; /* DBCS Support */
 
-    if (NLS_MB_CODE_PAGE_TAG) /* Is the system multi-byte codepage? */
-    {
-        gpsi->dwSRVIFlags |= (SRVINFO_DBCSENABLED | SRVINFO_IMM32); /* DBCS+IME Support */
-    }
+    if (UserIsIMMEnabled())
+        gpsi->dwSRVIFlags |= SRVINFO_IMM32; /* IME Support */
+
+    if (UserIsCiceroEnabled())
+        gpsi->dwSRVIFlags |= SRVINFO_CICERO_ENABLED; /* Cicero support */
 
     Setup = TRUE;
 

win32ss/user/ntuser/misc/registry.c

@@ -155,6 +155,36 @@ RegReadDWORD(HKEY hkey, PWSTR pwszValue, PDWORD pdwData)
     return NT_SUCCESS(Status);
 }
 
+NTSTATUS
+NTAPI
+RegOpenSectionKey(
+    LPCWSTR pszSection,
+    PHKEY phkey)
+{
+    WCHAR szKey[MAX_PATH] =
+        L"\\Registry\\Machine\\Software\\Microsoft\\Windows NT\\CurrentVersion\\";
+
+    RtlStringCchCatW(szKey, _countof(szKey), pszSection);
+    return RegOpenKey(szKey, phkey);
+}
+
+DWORD
+NTAPI
+RegGetSectionDWORD(LPCWSTR pszSection, LPWSTR pszValue, DWORD dwDefault)
+{
+    HKEY hKey;
+    DWORD dwValue;
+
+    if (NT_ERROR(RegOpenSectionKey(pszSection, &hKey)))
+        return dwDefault;
+
+    if (!RegReadDWORD(hKey, pszValue, &dwValue))
+        dwValue = dwDefault;
+
+    ZwClose(hKey);
+    return dwValue;
+}
+
 _Success_(return!=FALSE)
 BOOL
 NTAPI

win32ss/user/ntuser/simplecall.c

@@ -124,16 +124,11 @@ NtUserCallNoParam(DWORD Routine)
             break;
 
         case NOPARAM_ROUTINE_UPDATEPERUSERIMMENABLING:
-            // TODO: This should also check the registry!
-            // see https://www.pctipsbox.com/fix-available-for-ie7-memory-leaks-on-xp-sp3/ for more information
-            if (NLS_MB_CODE_PAGE_TAG)
-            {
+            if (UserIsIMMEnabled())
                 gpsi->dwSRVIFlags |= SRVINFO_IMM32;
-            }
             else
-            {
                 gpsi->dwSRVIFlags &= ~SRVINFO_IMM32;
-            }
+
             Result = TRUE; // Always return TRUE.
             break;
 

win32ss/user/ntuser/userfuncs.h

@@ -83,6 +83,9 @@ NTSTATUS FASTCALL InitSessionImpl(VOID);
 
 BOOL NTAPI InitMetrics(VOID);
 LONG NTAPI UserGetSystemMetrics(ULONG Index);
+BOOL FASTCALL UserIsDBCSEnabled(VOID);
+BOOL FASTCALL UserIsIMMEnabled(VOID);
+BOOL FASTCALL UserIsCiceroEnabled(VOID);
 
 /*************** KEYBOARD.C ***************/