unit GetWinVersionInfo;

interface

function GetOSInfo: string;

implementation

uses
  SysUtils, Windows, Registry;

function GetVersionExA(var lpVersionInformation: TOSVersionInfoEX): BOOL;
  stdcall; external kernel32;

var
  GetProductInfo: function (dwOSMajorVersion, dwOSMinorVersion,
                            dwSpMajorVersion, dwSpMinorVersion: DWORD;
                            var pdwReturnedProductType: DWORD): BOOL stdcall = NIL;

function GetOSInfo: string;
var
  NTBres, BRes: Boolean;
  OSVI: TOSVERSIONINFO;
  OSVI_NT: TOSVERSIONINFOEX;
  tmpStr: string;
  dwOSMajorVersion, dwOSMinorVersion,
  dwSpMajorVersion, dwSpMinorVersion,
  pdwReturnedProductType : DWORD;
begin
  Result := 'Error';
  NTBRes := FALSE;
  try
    OSVI_NT.dwOSVersionInfoSize := SizeOf(TOSVERSIONINFOEX);
    NTBRes := GetVersionExA(OSVI_NT);
    OSVI.dwOSVersionInfoSize := SizeOf(TOSVersionInfo);
    BRes := GetVersionEx(OSVI);
  except
    OSVI.dwOSVersionInfoSize := SizeOf(TOSVersionInfo);
    BRes := GetVersionEx(OSVI);
  end;
  if (not BRes) and (not NTBres) then
    Exit;
  Move( OSVI, OSVI_NT, SizeOf(TOSVersionInfo) );

  case OSVI_NT.dwPlatformId of
     VER_PLATFORM_WIN32_NT:
       begin
         if OSVI_NT.dwMajorVersion <= 4 then
           Result := 'Windows NT '
         else if (OSVI_NT.dwMajorVersion = 5) and (OSVI_NT.dwMinorVersion = 0) then
           Result := 'Windows 2000 '
         else if  (OSVI_NT.dwMajorVersion = 5) and (OSVI_NT.dwMinorVersion = 1) then
           Result := 'Windows XP '
         else if (OSVI_NT.dwMajorVersion >= 6) then
         begin
           if (OSVI_NT.dwMajorVersion=6) and (OSVI_NT.dwMinorVersion = 0) then
             Result := 'Windows Vista '
           else if (OSVI_NT.dwMajorVersion=6) and (OSVI_NT.dwMinorVersion = 1) then
             Result := 'Windows 7 '
           else if (OSVI_NT.dwMajorVersion=6) and (OSVI_NT.dwMinorVersion = 1) then
             Result := 'Windows 8 '
           else
             Result := 'Windows ';
           if Assigned(GetProductInfo) then
           begin
             dwOSMajorVersion := 6;
             dwOSMinorVersion := 0;
             dwSpMajorVersion := 0;
             dwSpMinorVersion := 0;
             GetProductInfo( dwOSMajorVersion, dwOSMinorVersion,
                             dwSpMajorVersion, dwSpMinorVersion,
                             pdwReturnedProductType );
             case pdwReturnedProductType of
               PRODUCT_BUSINESS:
                 tmpStr := 'Business Edition';
               PRODUCT_BUSINESS_N:
                 tmpStr := 'Business Edition';
               PRODUCT_CLUSTER_SERVER:
                 tmpStr := 'Cluster Server Edition';
               PRODUCT_DATACENTER_SERVER:
                 tmpStr := 'Server Datacenter Edition (full installation)';
               PRODUCT_DATACENTER_SERVER_CORE:
                 tmpStr := 'Server Datacenter Edition (core installation)';
               PRODUCT_ENTERPRISE:
                 tmpStr := 'Enterprise Edition';
               PRODUCT_ENTERPRISE_N:
                 tmpStr := 'Enterprise Edition';
               PRODUCT_ENTERPRISE_SERVER:
                 tmpStr := 'Server Enterprise Edition (full installation)';
               PRODUCT_ENTERPRISE_SERVER_CORE:
                 tmpStr := 'Server Enterprise Edition (core installation)';
               PRODUCT_ENTERPRISE_SERVER_IA64:
                 tmpStr := 'Server Enterprise Edition for Itanium-based Systems';
               PRODUCT_HOME_BASIC:
                 tmpStr := 'Home Basic Edition';
               PRODUCT_HOME_BASIC_N:
                 tmpStr := 'Home Basic Edition';
               PRODUCT_HOME_PREMIUM:
                 tmpStr := 'Home Premium Edition';
               PRODUCT_HOME_PREMIUM_N:
                 tmpStr := 'Home Premium Edition';
               PRODUCT_HOME_SERVER:
                 tmpStr := 'Home Server Edition';
               PRODUCT_SERVER_FOR_SMALLBUSINESS:
                 tmpStr := 'Server for Small Business Edition';
               PRODUCT_SMALLBUSINESS_SERVER:
                 tmpStr := 'Small Business Server';
               PRODUCT_SMALLBUSINESS_SERVER_PREMIUM:
                 tmpStr := 'Small Business Server Premium Edition';
               PRODUCT_STANDARD_SERVER:
                 tmpStr := 'Server Standard Edition (full installation)';
               PRODUCT_STANDARD_SERVER_CORE:
                 tmpStr := 'Server Standard Edition (core installation)';
               PRODUCT_STARTER:
                 tmpStr := 'Starter Edition';
               PRODUCT_STORAGE_ENTERPRISE_SERVER:
                 tmpStr := 'Storage Server Enterprise Edition';
               PRODUCT_STORAGE_EXPRESS_SERVER:
                 tmpStr := 'Storage Server Express Edition';
               PRODUCT_STORAGE_STANDARD_SERVER:
                 tmpStr := 'Storage Server Standard Edition';
               PRODUCT_STORAGE_WORKGROUP_SERVER:
                 tmpStr := 'Storage Server Workgroup Edition';
               PRODUCT_UNDEFINED:
                 tmpStr := 'An unknown product';
               PRODUCT_ULTIMATE:
                 tmpStr := 'Ultimate Edition';
               PRODUCT_ULTIMATE_N:
                 tmpStr := 'Ultimate Edition';
               PRODUCT_WEB_SERVER:
                 tmpStr := 'Web Server Edition';
               PRODUCT_UNLICENSED:
                 tmpStr := 'Unlicensed product'
             else
               tmpStr := '';
             end;{ pdwReturnedProductType }
             Result := Result + tmpStr;
             NTBRes := FALSE;
           end;{ GetProductInfo<>NIL }
         end;{ Vista }
         if NTBres then
         begin
           if OSVI_NT.wProductType = VER_NT_WORKSTATION then
           begin
             if OSVI_NT.wProductType = VER_NT_WORKSTATION then
             begin
               case OSVI_NT.wSuiteMask of
                 512: Result := Result + 'Personal';
                 768: Result := Result + 'Home Premium';
               else
                 Result := Result + 'Professional';
               end;
             end
             else if OSVI_NT.wProductType = VER_NT_SERVER then
             begin
               if OSVI_NT.wSuiteMask = VER_SUITE_DATACENTER then
                 Result := Result + 'DataCenter Server'
               else if OSVI_NT.wSuiteMask = VER_SUITE_ENTERPRISE then
                 Result :=  Result + 'Advanced Server'
               else
                 Result := Result + 'Server';
             end;
           end{ wProductType=VER_NT_WORKSTATION }
           else
           begin
             with TRegistry.Create do
               try
                 RootKey := HKEY_LOCAL_MACHINE;
                 if OpenKeyReadOnly('SYSTEM\CurrentControlSet\Control\ProductOptions') then
                   try
                     tmpStr := UpperCase(ReadString('ProductType'));
                     if tmpStr = 'WINNT' then
                       Result := Result + 'Workstation';
                     if tmpStr = 'SERVERNT' then
                       Result := Result + 'Server';
                   finally
                     CloseKey;
                   end;
               finally
                 Free;
               end;
             end;{ wProductType<>VER_NT_WORKSTATION }
           end;{ NTBRes }
         end;{ VER_PLATFORM_WIN32_NT }
     VER_PLATFORM_WIN32_WINDOWS:
       begin
         if (OSVI.dwMajorVersion = 4) and (OSVI.dwMinorVersion = 0) then
         begin
           Result := 'Windows 95 ';
           if OSVI.szCSDVersion[1] = 'C' then
             Result := Result + 'OSR2';
         end;
         if (OSVI.dwMajorVersion = 4) and (OSVI.dwMinorVersion = 10) then
         begin
           Result := 'Windows 98 ';
           if OSVI.szCSDVersion[1] = 'A' then
             Result := Result + 'SE';
         end;
         if (OSVI.dwMajorVersion = 4) and (OSVI.dwMinorVersion = 90) then
           Result := 'Windows Me';
       end;{ VER_PLATFORM_WIN32_WINDOWS }
     VER_PLATFORM_WIN32s:
       Result := 'Microsoft Win32s';
  else
    Result := 'Unknown';
  end;{ OSVI_NT.dwPlatformId }
end;{ GetOSInfo }

initialization
   @GetProductInfo := GetProcAddress(GetModuleHandle('KERNEL32.DLL'),
                                     'GetProductInfo');

end.