【转载】从文件句柄获得全路径

typedef NTSTATUS (NTAPI *PFN_ZwQueryObject)( 
    IN HANDLE ObjectHandle, 
    IN ULONG ObjectInformationClass, 
    OUT PVOID ObjectInformation, 
    IN ULONG ObjectInformationLength, 
    OUT PULONG ReturnLength OPTIONAL 
    ); 

PFN_ZwQueryObject g_ZwQueryObject = (PFN_ZwQueryObject)GetProcAddress(GetModuleHandle(TEXT("ntdll.dll")),"ZwQueryObject");


  
BOOL GetPathByHandle(HANDLE hFile, LPWSTR lpBuf, DWORD nBuf) 
{ 
    ULONG m, n; 
    WCHAR lpPath[MAX_PATH+4]; 
    WCHAR lpDrive[MAX_PATH]; 
    WCHAR lpDevName[MAX_PATH]; 
    if (g_ZwQueryObject(hFile, 1, lpPath, MAX_PATH+4, &m) >= 0 && 
        (m = GetLogicalDriveStringsW(MAX_PATH, lpDrive)) && m < MAX_PATH) 
    { 
        WCHAR *p = lpDrive; 
        while (m = wcslen(p)) 
        { 
            p[m-1] = L'\0'; 
            n = QueryDosDeviceW(p, lpDevName, MAX_PATH); 
            if (n && n < MAX_PATH) 
            { 
                n = wcslen(lpDevName); 
                if (!wcsnicmp(lpPath+4, lpDevName, n)) 
                { 
                    wcsncpy(lpBuf, p, nBuf); 
                    if (nBuf > 2) wcsncpy(lpBuf+2, lpPath+4+n, nBuf-2); 
                    return TRUE; 
                } 
            } 
            p += m + 1; 
        } 
    } 
    return FALSE; 
}