服务程序中如何得到当前登陆用户名

//根据进程名称得到进程token
BOOL GetTokenByName(HANDLE &hToken,LPSTR lpName)
{
if(!lpName)
{
return FALSE;
}
HANDLE         hProcessSnap = NULL;
BOOL           bRet      = FALSE;
PROCESSENTRY32 pe32      = {0};

hProcessSnap = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
if (hProcessSnap == INVALID_HANDLE_VALUE)
return (FALSE);

pe32.dwSize = sizeof(PROCESSENTRY32);

if (Process32First(hProcessSnap, &pe32))
{
do
{
if(!strcmp(_strupr(pe32.szExeFile),_strupr(lpName)))
{
HANDLE hProcess = OpenProcess(PROCESS_QUERY_INFORMATION,
FALSE,pe32.th32ProcessID);
bRet = OpenProcessToken(hProcess, TOKEN_ALL_ACCESS,&hToken);
CloseHandle (hProcessSnap);
return (bRet);
}
}
while (Process32Next(hProcessSnap, &pe32));
bRet = TRUE;
}
else
bRet = FALSE;

CloseHandle (hProcessSnap);
return (bRet);
}

BOOL GetCurrentUserName()
{
HANDLE hToken;

//得到shell的token
if(!GetTokenByName(hToken,"EXPLORER.EXE"))
{
return FALSE;
}
DWORD        cbti     = 0;
PTOKEN_USER  ptiUser  = NULL;
SID_NAME_USE snu;

//取得所需空间大小
if (GetTokenInformation(hToken, TokenUser, NULL, 0, &cbti))
{
CloseHandle(hToken);
return FALSE;
}

//分配空间
ptiUser = (PTOKEN_USER) HeapAlloc(GetProcessHeap(), 0, cbti);
if(!ptiUser)
{
CloseHandle(hToken);
return FALSE;
}

//取得token信息
if (!GetTokenInformation(hToken, TokenUser, ptiUser, cbti, &cbti))
{
CloseHandle(hToken);
HeapFree(GetProcessHeap(), 0, ptiUser);
return FALSE;
}

char szUser[50];
char szDomain[50];
DWORD nUser = 50;
DWORD nDomain = 50;

//根据用户的sid得到用户名和domain

if (!LookupAccountSid(NULL, ptiUser->User.Sid, szUser, &nUser,
szDomain, &nDomain, &snu))
{
CloseHandle(hToken);
HeapFree(GetProcessHeap(), 0, ptiUser);
return FALSE;
}
OutputDebugString(szUser);
OutputDebugString("\r\n");
OutputDebugString(szDomain);
OutputDebugString("\r\n");

CloseHandle(hToken);
HeapFree(GetProcessHeap(), 0, ptiUser);
return TRUE;
}