INT FASTCALL
IntGdiAddFontResourceEx(PUNICODE_STRING FileName, DWORD Characteristics,
                        BOOL bWriteRegistry)
{
    ...
}

INT FASTCALL
IntGdiAddFontResource(PUNICODE_STRING FileName, DWORD Characteristics)
{
    return IntGdiAddFontResourceEx(FileName, Characteristics, FALSE);
}

BOOL FASTCALL
IntLoadFontsInRegistry(PLIST_ENTRY pHead)
{
    NTSTATUS                        Status;
    HANDLE                          KeyHandle;
    OBJECT_ATTRIBUTES               ObjectAttributes;
    KEY_FULL_INFORMATION            KeyFullInfo;
    ULONG                           i, Length;
    UNICODE_STRING                  FontTitleW, FontPathW, FileNameW;
    BYTE                            InfoBuffer[128];
    PKEY_VALUE_FULL_INFORMATION     pInfo;
    LPWSTR                          pch;
    PFONTSUBST_ENTRY                pEntry;
    BOOLEAN                         Success;
    WCHAR                           szPath[MAX_PATH];
    INT                             nFontCount = 0;

    /* open registry key */
    InitializeObjectAttributes(&ObjectAttributes, &g_FontRegPath,
                               OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
                               NULL, NULL);
    Status = ZwOpenKey(&KeyHandle, KEY_READ, &ObjectAttributes);
    if (!NT_SUCCESS(Status))
    {
        DPRINT("ZwOpenKey failed: 0x%08X\n", Status);
        return FALSE;   /* failure */
    }

    /* query count of values */
    Status = ZwQueryKey(KeyHandle, KeyFullInformation,
                        &KeyFullInfo, sizeof(KeyFullInfo), &Length);
    if (!NT_SUCCESS(Status))
    {
        DPRINT("ZwQueryKey failed: 0x%08X\n", Status);
        ZwClose(KeyHandle);
        return FALSE;   /* failure */
    }

    /* for each value */
    for (i = 0; i < KeyFullInfo.Values; ++i)
    {
        /* get value name */
        Status = ZwEnumerateValueKey(KeyHandle, i, KeyValueFullInformation,
                                     InfoBuffer, sizeof(InfoBuffer), &Length);
        if (!NT_SUCCESS(Status))
        {
            DPRINT("ZwEnumerateValueKey failed: 0x%08X\n", Status);
            break;      /* failure */
        }

        /* create FontTitleW string */
        pInfo = (PKEY_VALUE_FULL_INFORMATION)InfoBuffer;
        Length = pInfo->NameLength / sizeof(WCHAR);
        pInfo->Name[Length] = UNICODE_NULL;   /* truncate */
        Success = RtlCreateUnicodeString(&FontTitleW, pInfo->Name);
        if (!Success)
        {
            Status = STATUS_INSUFFICIENT_RESOURCES;
            DPRINT("RtlCreateUnicodeString failed\n");
            break;      /* failure */
        }

        /* query value */
        Status = ZwQueryValueKey(KeyHandle, &FontTitleW, KeyValueFullInformation, 
                                 InfoBuffer, sizeof(InfoBuffer), &Length);
        pInfo = (PKEY_VALUE_FULL_INFORMATION)InfoBuffer;
        if (!NT_SUCCESS(Status) || !pInfo->DataLength)
        {
            DPRINT("ZwQueryValueKey failed: 0x%08X\n", Status);
            RtlFreeUnicodeString(&FontTitleW);
            break;      /* failure */
        }

        /* create FontPathW string */
        pch = (LPWSTR)((PUCHAR)pInfo + pInfo->DataOffset);
        Length = pInfo->DataLength / sizeof(WCHAR);
        pch[Length] = UNICODE_NULL; /* truncate */
        Success = RtlCreateUnicodeString(&FontPathW, pch);
        if (!Success)
        {
            Status = STATUS_INSUFFICIENT_RESOURCES;
            DPRINT("RtlCreateUnicodeString failed\n");
            RtlFreeUnicodeString(&FontTitleW);
            break;      /* failure */
        }

        if (PathIsRelativeW(pch))
        {
            GetWindowsDirectoryW(szPath, ARRAYSIZE(szPath));
            StringCbCatW(szPath, ARRAYSIZE(szPath), L"\\Fonts\\");
            StringCbCatW(szPath, ARRAYSIZE(szPath), pch);
        }
        else
        {
            StringCbCopy(szPath, ARRAYSIZE(szPath), pch);
        }

        /* Load font(s) without writing registry */
        RtlCreateUnicodeString(&FileNameW, szPath);
        nFontCount += IntGdiAddFontResourceEx(&FileNameW, 0, TRUE);
        RtlFreeUnicodeString(&FileNameW);

        RtlFreeUnicodeString(&FontTitleW);
        RtlFreeUnicodeString(&FontPathW);
    }

    /* close now */
    ZwClose(KeyHandle);

    if (KeyFullInfo.Values == 0 || nFontCount == 0)
    {
        DPRINT1("Fonts registry is empty.\n");
        /* Load font(s) with writing registry */
        IntLoadSystemFonts();
        return TRUE;
    }

    return NT_SUCCESS(Status);
}