unit NetworkUnit;

interface

uses
  Windows, SysUtils,
  WinSock;

type
  TNetworkInfo = record
    HostName: String;
    IPAddress: String;
  end;

function GetMachineNetworkInfo: TNetworkInfo;
function GetHostName(Ip : String) : String;
function GetIpAddress(HostName : String) : String;
function GetNetUser : Ansistring;

type
  THostInfo = record
    HostName: String;
    IPAddress: String;
    AnotherNames: array of String;
  end;

function GetHostInfo(NetworkName: String): THostInfo;

implementation


{-------------------------------
//  自マシンのマシン名とIPアドレスを取得する
備考:       uses WinSockが必要
履歴:       2003/11/12
//--▼----------------------▽--}
function GetMachineNetworkInfo: TNetworkInfo;
var
   wsaData  : TWsaData;
   hostName : array [0..255] of AnsiChar;
   host     : PHostEnt;
   in_addr  : TInAddr;
begin
   WSAStartup($101, wsaData);
   WinSock.gethostname(hostName,sizeof(hostName));
   host     := gethostbyname(hostName);
   in_addr  :=PInAddr(PInAddr(host^.h_addr_list)^)^;
   Result.HostName :=String(hostName);
   Result.IPAddress :=String(inet_ntoa(in_addr));
   WSACleanup;
end;
//--△----------------------▲--


{-------------------------------
//  IPアドレスからhost名を求める
備考:       uses Winsockが必要
履歴:       2003/11/12
            2006/04/04 若干簡単になるように修正
            2008/02/06
              inet_addrとWSAStartupの行を入れ替えた
//--▼----------------------▽--}
function GetHostName(Ip : String) : String;
var
  PH : PHostEnt;
  InAddr: TInAddr;
  WSADATA : TWSADATA;
begin
  Result := '';
  if Ip = '' then exit;
  WSAStartup(MakeWord(1,1) , WSADATA);  //MakeWord(1,1)=$0101
  InAddr.S_addr := inet_addr(PAnsiChar(Ip));

  PH := gethostbyaddr(@InAddr,4,PF_INET);

  if PH = nil then Exit;
  Result := string(ph^.h_name);
  WSACleanup;
end;
//--△----------------------▲--

{-------------------------------
//  host名からIPアドレスを求める
備考:       uses Winsockが必要
履歴:       2006/04/04
//--▼----------------------▽--}
function GetIpAddress(HostName : String) : String;
var
  PH : PHostEnt;
  InAddr: TInAddr;
  WSADATA : TWSADATA;
begin
  Result := '';
  if HostName = '' then exit;
  WSAStartup(MakeWord(1,1), WSADATA);

  PH := gethostbyname(PAnsiChar(HostName));

  if PH = nil then Exit;
  InAddr := PInAddr(ph^.h_addr_list^)^;
  Result := inet_ntoa(InAddr);
  WSACleanup;
end;
//--△----------------------▲--

{-------------------------------
//  ログイン中のユーザー名を取得する
備考:       uses SysUtils
履歴:       2008/02/01
//--▼----------------------▽--}
function GetNetUser : Ansistring;
var
  dwI : DWord;
begin
  dwI := MAX_PATH;
  SetLength (Result, dwI + 1);
  if WNetGetUser (Nil, PChar (Result), dwI) = NO_ERROR then
    SetLength (Result, StrLen (PChar (Result)))
  else
    SetLength (Result, 0)
end;
//--△----------------------▲--

{-------------------------------
//  host名かIPアドレスからhost情報を求める
引数:       host名かIPアドレスを渡す
戻り値:     ホスト名/IPアドレス/ホスト別名
            ホスト別名は文字列の動的配列で戻るようになる
備考:       uses Winsockが必要
履歴:       2008/02/06
//--▼----------------------▽--}
function GetHostInfo(NetworkName: String): THostInfo;
type PPChar=^PChar;
var
  PH : PHostEnt;
  InAddr: TInAddr;
  WSADATA : TWSADATA;

  ppc: PPChar;
begin
  Result.HostName := '';
  Result.IPAddress := '';
  SetLength(Result.AnotherNames, 0);
  if NetworkName='' then Exit;

  WSAStartup(MakeWord(1,1) , WSADATA);
  InAddr.S_addr := inet_addr(PAnsiChar(NetworkName));
  if InAddr.S_addr = INADDR_NONE then
  begin
    PH := gethostbyname(PAnsiChar(NetworkName));
  end else
  begin
    PH := gethostbyaddr(@(InAddr.S_addr), 4, AF_INET);
  end;

  Result.HostName := PH^.h_name;
  Result.IPAddress := inet_ntoa(PInAddr(PH^.h_addr_list^)^);

  ppc:=PPChar(PH^.h_aliases);
  while assigned(ppc^) do begin
    SetLength(Result.AnotherNames, Length(Result.AnotherNames)+1);
    Result.AnotherNames[Length(Result.AnotherNames)-1] := ppc^;
    inc(ppc);
  end;

  WSACleanUp;
end;
//--△----------------------▲--

end.