fmainform.pas

< Delphi网络通信协议分析与应用实现>>一书的源代码。

unit fmainform;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, Menus, ScktComp, ExtCtrls, StdCtrls, Buttons,setuser;
type
    session_record=record
        IsAuth:boolean;                      {是否被授权}
        Used: boolean;                       {会话记录是否可用}
        SS_Handle: integer;                  {代理服务器套接字句柄}
        CSocket: TClientSocket;              {用于连接远程的套接字}
        Lookingup: boolean;                  {是否正在查找服务器}
        LookupTime: integer;                 {查找服务器时间}
        Request: boolean;                    {是否有请求}
        request_str: string;                 {请求数据块}
        client_connected: boolean;           {客户机联机标志}
        remote_connected: boolean;           {远程服务器连接标志}
end;


type
  TMainForm = class(TForm)
    MainMenu1: TMainMenu;
    ProxySerSkt1: TServerSocket;
    ProxyCltSkt1: TClientSocket;
    N11: TMenuItem;
    N5: TMenuItem;
    Timer1: TTimer;
    Memo1: TMemo;
    GroupBox1: TGroupBox;
    Label1: TLabel;
    Edit1: TEdit;
    N1: TBitBtn;
    N2: TBitBtn;
    N3: TMenuItem;
    N4: TMenuItem;
    procedure N1Click(Sender: TObject);
    procedure N2Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure N5Click(Sender: TObject);
    procedure ProxySerSkt1Listen(Sender: TObject;
      Socket: TCustomWinSocket);
    procedure ProxySerSkt1ClientConnect(Sender: TObject;
      Socket: TCustomWinSocket);
    procedure ProxySerSkt1ClientDisconnect(Sender: TObject;
      Socket: TCustomWinSocket);
    procedure ProxySerSkt1ClientError(Sender: TObject;
      Socket: TCustomWinSocket; ErrorEvent: TErrorEvent;
      var ErrorCode: Integer);
    procedure ProxySerSkt1ClientRead(Sender: TObject;
      Socket: TCustomWinSocket);
    procedure ProxyCltSkt1Connect(Sender: TObject;
      Socket: TCustomWinSocket);
    procedure ProxyCltSkt1Disconnect(Sender: TObject;
      Socket: TCustomWinSocket);
    procedure ProxyCltSkt1Error(Sender: TObject; Socket: TCustomWinSocket;
      ErrorEvent: TErrorEvent; var ErrorCode: Integer);
    procedure ProxyCltSkt1Write(Sender: TObject;
      Socket: TCustomWinSocket);
    procedure ProxyCltSkt1Read(Sender: TObject; Socket: TCustomWinSocket);
    procedure Timer1Timer(Sender: TObject);

    procedure AppException(Sender: TObject; E: Exception);
    function CheckIP(IP:string):boolean;
    procedure N4Click(Sender: TObject);
    
  private
    { Private declarations }
  public
    { Public declarations }
    Service_Enabled: boolean;           {代理服务是否开启}
    session: array of session_record;      {会话数组}
    sessions: integer;                  {会话数}
    LookUpTimeOut: integer;           {连接超时值}
    InvalidRequests: integer;            {无效请求数}

  end;

var
  MainForm: TMainForm;

implementation

{$R *.dfm}

procedure TMainForm.N1Click(Sender: TObject);
begin
    ProxySerSkt1.Active:=true;    {开启服务}
end;

procedure TMainForm.N2Click(Sender: TObject);
begin
    ProxySerSkt1.Active:=false;      {停止服务}
    N1.Enabled:=True;
    N2.Enabled:=False;
    Service_Enabled:=false;           {标志清零}
end;

procedure TMainForm.FormCreate(Sender: TObject);
begin
    Service_Enabled:=false;
    sessions:=0;               {会话数=0}
    Application.OnException := AppException;     {为了屏蔽代理服务器出现的异常}
    invalidRequests:=0;           {0错误}
    LookUpTimeOut:=60000;      {超时值=1分钟}
    timer1.Enabled:=true;         {打开定时器}
    n1.Enabled:=false;           {开启服务按钮项失效}
    n2.Enabled:=true;           {关闭服务按钮项有效}
    ProxySerSkt1.Port:=988;      {代理服务器端口=988}
    ProxySerSkt1.Active:=true;    {开启服务}
end;

procedure TMainForm.FormClose(Sender: TObject; var Action: TCloseAction);
begin
    timer1.Enabled:=false;          {关闭定时器}
    if Service_Enabled then
        ProxySerSkt1.Active:=false;   {退出程序时关闭服务}

end;

procedure TMainForm.N5Click(Sender: TObject);
begin
   MainForm.Close;                     {退出程序}
end;

procedure TMainForm.ProxySerSkt1Listen(Sender: TObject;
  Socket: TCustomWinSocket);
begin
    Service_Enabled:=true;            {置正在服务标志}
    N1.Enabled:=false;
    N2.Enabled:=true;
end;

procedure TMainForm.ProxySerSkt1ClientConnect(Sender: TObject;
  Socket: TCustomWinSocket);
var
i,j: integer;
begin
    j:=-1;
    for i:=1 to sessions do               {查找是否有空白项}
        if not session[i-1].Used and not session[i-1].CSocket.active then
        begin
            j:=i-1;                      {有，分配它}
            session[j].Used:=true;       {置为在用}
            break;
        end
        else
            if not session[i-1].Used and session[i-1].CSocket.active then
                session[i-1].CSocket.active:=false;
        if j=-1 then
        begin                              {无，新增一个}
            j:=sessions;
            inc(sessions);
            setlength(session,sessions);
            session[j].Used:=true;                        {置为在用}
            session[j].CSocket:=TClientSocket.Create(nil);
            session[j].CSocket.OnConnect:=ProxyCltSkt1Connect;
            session[j].CSocket.OnDisconnect:=ProxyCltSkt1Disconnect;
            session[j].CSocket.OnError:=ProxyCltSkt1Error;
            session[j].CSocket.OnRead:=ProxyCltSkt1Read;
            session[j].CSocket.OnWrite:=ProxyCltSkt1Write;
            session[j].Lookingup:=false;
        end;
    session[j].SS_Handle:=socket.socketHandle;    {保存句柄，实现绑定}
    session[j].Request:=false;                    {无请求}
    session[j].client_connected:=true;            {客户机已连接}
    session[j].remote_connected:=false;           {远程未连接}
    session[j].IsAuth:=checkip(socket.RemoteAddress);

    edit1.text:=inttostr(sessions);
end;

procedure TMainForm.ProxySerSkt1ClientDisconnect(Sender: TObject;
  Socket: TCustomWinSocket);
var
i,j,k: integer;
begin
    for i:=1 to sessions do
        if (session[i-1].SS_Handle=socket.SocketHandle) and session[i-1].Used then
        begin
            session[i-1].client_connected:=false;   {客户机未连接}
            if session[i-1].remote_connected then
                session[i-1].CSocket.active:=false   {假如远程尚连接，断开它}
            else
                session[i-1].Used:=false;           {假如两者都断开，则置释放资源标志}
            break;
        end;
    j:=sessions;
    k:=0;
    for i:=1 to j do                        {统计会话数组尾部有几个未用项}
    begin
        if session[j-i].Used then
            break;
        inc(k);
    end;
    if k>0 then                          {修正会话数组，释放尾部未用项}
    begin
        sessions:=sessions-k;
        setlength(session,sessions);
    end;
    edit1.text:=inttostr(sessions);
end;

procedure TMainForm.ProxySerSkt1ClientError(Sender: TObject;
  Socket: TCustomWinSocket; ErrorEvent: TErrorEvent;
  var ErrorCode: Integer);
var
i,j,k: integer;
begin
    for i:=1 to sessions do
        if (session[i-1].SS_Handle=socket.SocketHandle) and session[i-1].Used then
        begin
            session[i-1].client_connected:=false;   {客户机未连接}
            if session[i-1].remote_connected then
                session[i-1].CSocket.active:=false   {假如远程尚连接，断开它}
            else
                session[i-1].Used:=false;           {假如两者都断开，则置释放资源标志}
            break;
        end;
    j:=sessions;
    k:=0;
    for i:=1 to j do
    begin
        if session[j-i].Used then
            break;
        inc(k);
    end;
    if k>0 then
    begin
        sessions:=sessions-k;
        setlength(session,sessions);
    end;
    edit1.text:=inttostr(sessions);
    errorcode:=0;
end;

procedure TMainForm.ProxySerSkt1ClientRead(Sender: TObject;
  Socket: TCustomWinSocket);
var
tmp,line,host: string;
i,j,port: integer;
begin
    for i:=1 to sessions do                 {判断是哪一个会话}
    begin
        if session[i-1].Used and (session[i-1].SS_Handle=socket.sockethandle) then
        begin
            session[i-1].request_str:=socket.ReceiveText;  {保存请求数据}
            tmp:=session[i-1].request_str;                 {存放到临时变量}