{
文件名：RealICQSocket.pas
功  能：此单元定义了一些Winsock应用的基本（公用）过程,函数和类型。
建  立：尹进
历  史：
2005.12.23：补文件说明信息（尹进）
}
unit RealICQSocket;

interface

uses
  WinSock2,
  SysUtils;

type
  //Socket异常类
  TSocketException = class(Exception);

  //IP地址类型
  TIPVersion = (ipV4 = 0, ipV6 = 1);

  //初始化WinSock2
  procedure InitWinSock2;
  //释放已分配的WinSock2资源
  procedure FreeWinSock2;
  
  function HostToIP(Name: string; var Ip: string): Boolean;
  function GetHostIP(HostName: String): String;
  function GetLocalIP: String;

  
implementation

//------------------------------------------------------------------------------
procedure InitWinSock2;
var
  aWSAData: TWSAData;
begin
  if WSAStartup($202, aWSAData) <> 0 then
  begin
    raise TSocketException.Create('初始化WinSock2失败，请确认系统是否正确安装了WinSock2');
  end;
end;

//------------------------------------------------------------------------------
procedure FreeWinSock2;
begin
  if WSACleanup() <> 0 then
  begin
    raise TSocketException.Create('清除WinSock2资源失败，错误代码：' + IntToStr( WSAGetLastError() ) );
  end;
end;

//------------------------------------------------------------------------------
{域名解析}
function HostToIP(Name: string; var Ip: string): Boolean;
var
  hostName : array [0..255] of char;
  hostEnt : PHostEnt;
  addr : PChar;
begin
    gethostname (hostName, sizeof (hostName));
    StrPCopy(hostName, Name);
    hostEnt := gethostbyname (hostName);
    if Assigned (hostEnt) then
      if Assigned (hostEnt^.h_addr_list) then begin
        addr := hostEnt^.h_addr_list^;
        if Assigned (addr) then begin
          IP := Format ('%d.%d.%d.%d', [byte (addr [0]),
          byte (addr [1]), byte (addr [2]), byte (addr [3])]);
          Result := True;
        end
        else
          Result := False;
      end
      else
        Result := False
    else begin
      Result := False;
    end;
end;

//------------------------------------------------------------------------------
{获取IP地址}
function GetHostIP(HostName: String): String;
var
   buf:pChar;
   hostent:PHostEnt;
begin
   Result := '';
   buf := Allocmem(60);
   strcopy(buf,PChar(HostName));
   if Trim(buf)='' then
      gethostname(buf,60);
   hostent := gethostbyname(buf);
   Freemem(buf,60);
   if hostent=nil then
      Exit;
   Result  := inet_ntoa(pinAddr(hostent^.h_addr^)^);
end;

//获取本机所有IP地址，IP地址之间用“,”隔开
function GetLocalIP: String;
type
  TaPInAddr = Array[0..10] of PInAddr;
  PaPInAddr = ^TaPInAddr;
var
  phe: PHostEnt;
  pptr: PaPInAddr;
  Buffer: Array[0..63] of Char;
  I: Integer;
  IP: String;
begin
  IP:='';
  GetHostName(Buffer, SizeOf(Buffer));
  phe := GetHostByName(buffer);
  if phe = nil then
  begin
    Result:=IP;
    exit;
  end;
  
  pPtr := PaPInAddr(phe^.h_addr_list);
  I := 0;
  while pPtr^[I] <> nil do
  begin
    if IP = '' then
      IP := inet_ntoa(pptr^[I]^)
    else
      IP := IP + ',' + inet_ntoa(pptr^[I]^);
    Inc(I);
  end;
  
  Result:=IP;
end;

initialization
  InitWinSock2;

finalization
  FreeWinSock2;

end.