本篇是創(chuàng)建游戲內(nèi)核（23）的續(xù)篇，涉及到的DirectPlay基礎知識請參閱使用DirectPlay進行網(wǎng)絡互聯(lián)（2），使用DirectPlay進行網(wǎng)絡互聯(lián)（3）。
使用NETWORK_SERVER處理服務器
可以使用類NETWORK_SERVER來處理網(wǎng)絡服務器端，這個類用于初始化DirectPlay服務器對象，主持游戲會話，處理收到和
要發(fā)送的網(wǎng)絡消息。
來看看它的定義：
//====================================================================================
// This class encapsulate server how to communicate with client.
//====================================================================================
typedef class NETWORK_SERVER
{
public:
NETWORK_SERVER();
virtual ~NETWORK_SERVER();
IDirectPlay8Server* get_server();
BOOL init();
BOOL shutdown();
BOOL host(const GUID* guid_adapter, long port, const char* session_name,
const char* session_pwd = NULL, long max_players = 0);
BOOL disconnect();
BOOL is_connected();
BOOL send_data(DPNID player_id, void* data, ulong size, ulong flags = 0);
BOOL send_text(DPNID player_id, char* text, ulong flags = 0);
BOOL disconnect_player(long player_id);
BOOL get_ip(char* ip, ulong player_id = 0);
BOOL get_name(char* name, ulong player_id);
long get_port();
BOOL get_session_name(char* session_name);
BOOL get_session_pwd(char* session_pwd);
long get_max_players();
long get_cur_players_num();
protected:
static HRESULT WINAPI _network_msg_handler(PVOID user_context, DWORD msg_id, PVOID msg_buffer);
virtual BOOL _add_player_to_group(DPNMSG_ADD_PLAYER_TO_GROUP* msg) { return TRUE; }
virtual BOOL _async_op_complete(DPNMSG_ASYNC_OP_COMPLETE* msg) { return TRUE; }
virtual BOOL _client_info(DPNMSG_CLIENT_INFO* msg) { return TRUE; }
virtual BOOL _connect_complete(DPNMSG_CONNECT_COMPLETE* msg) { return TRUE; }
virtual BOOL _create_group(DPNMSG_CREATE_GROUP* msg) { return TRUE; }
virtual BOOL _create_player(DPNMSG_CREATE_PLAYER* msg) { return TRUE; }
virtual BOOL _destroy_group(DPNMSG_DESTROY_GROUP* msg) { return TRUE; }
virtual BOOL _destroy_player(DPNMSG_DESTROY_PLAYER* msg) { return TRUE; }
virtual BOOL _enum_hosts_query(DPNMSG_ENUM_HOSTS_QUERY* msg) { return TRUE; }
virtual BOOL _enum_hosts_response(DPNMSG_ENUM_HOSTS_RESPONSE* msg) { return TRUE; }
virtual BOOL _group_info(DPNMSG_GROUP_INFO* msg) { return TRUE; }
virtual BOOL _host_migrate(DPNMSG_HOST_MIGRATE* msg) { return TRUE; }
virtual BOOL _indicate_connect(DPNMSG_INDICATE_CONNECT* msg) { return TRUE; }
virtual BOOL _indicated_connect_aborted(DPNMSG_INDICATED_CONNECT_ABORTED* msg) { return TRUE; }
virtual BOOL _peer_info(DPNMSG_PEER_INFO* msg) { return TRUE; }
virtual BOOL _receive(DPNMSG_RECEIVE* msg) { return TRUE; }
virtual BOOL _remove_player_from_group(DPNMSG_REMOVE_PLAYER_FROM_GROUP* msg) { return TRUE; }
virtual BOOL _return_buffer(DPNMSG_RETURN_BUFFER* msg) { return TRUE; }
virtual BOOL _send_complete(DPNMSG_SEND_COMPLETE* msg) { return TRUE; }
virtual BOOL _server_info(DPNMSG_SERVER_INFO* msg) { return TRUE; }
virtual BOOL _terminate_session(DPNMSG_TERMINATE_SESSION* msg) { return TRUE; }
protected:
IDirectPlay8Server* _server;
BOOL _is_connected;
long _port;
char _session_name[MAX_PATH];
char _session_pwd[MAX_PATH];
long _max_players;
long _cur_players_num;
} *NETWORK_SERVER_PTR;
類的實現(xiàn)：
//---------------------------------------------------------------------------------
// Constructor, zero member data.
//---------------------------------------------------------------------------------
NETWORK_SERVER::NETWORK_SERVER()
{
memset(this, 0, sizeof(*this) - 4);
}
//---------------------------------------------------------------------------------
// Destructor, shutdown server.
//---------------------------------------------------------------------------------
NETWORK_SERVER::~NETWORK_SERVER()
{
shutdown();
}
//---------------------------------------------------------------------------------
// Shutdown server.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::shutdown()
{
if(! disconnect())
return FALSE;
_server = NULL;
return TRUE;
}
//---------------------------------------------------------------------------------
// Disconnect server to all clients.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::disconnect()
{
if(_server)
{
// closes the open connection to a session
if(FAILED(_server->Close(0)))
return FALSE;
}
_is_connected = FALSE;
_port = 0;
_session_name[0] = NULL;
_session_pwd[0] = NULL;
_max_players = 0;
_cur_players_num = 0;
return TRUE;
}
//---------------------------------------------------------------------------------
// Return pointer to IDirectPlay8Server object.
//---------------------------------------------------------------------------------
IDirectPlay8Server* NETWORK_SERVER::get_server()
{
return _server;
}
//---------------------------------------------------------------------------------
// Create IDirectPlay8Server object.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::init()
{
// shutdown old server object first
shutdown();
// create the server object
if(FAILED(CoCreateInstance(CLSID_DirectPlay8Server, NULL, CLSCTX_INPROC, IID_IDirectPlay8Server,
(void**) &_server)))
{
return FALSE;
}
return TRUE;
}
//---------------------------------------------------------------------------------
// Host server.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::host(const GUID* guid_adapter, long port,
const char* session_name, const char* session_pwd, long max_players)
{
// disconnect from current connection
disconnect();
_port = port;
// error checking
if(_server == NULL || session_name == NULL || port == 0)
return FALSE;
// initialize the server object
if(FAILED(_server->Initialize((PVOID)this, _network_msg_handler, 0)))
return FALSE;
IDirectPlay8Address* dp_address;
// create an address object
if(FAILED(CoCreateInstance(CLSID_DirectPlay8Address, NULL, CLSCTX_INPROC, IID_IDirectPlay8Address,
(void**) &dp_address)))
return FALSE;
DPN_APPLICATION_DESC app_desc;
WCHAR w_session_name[MAX_PATH], w_session_pwd[MAX_PATH];
// set protocol
if(FAILED(dp_address->SetSP(&CLSID_DP8SP_TCPIP)))
goto fail;
// set the port - must not be 0
if(FAILED(dp_address->AddComponent(DPNA_KEY_PORT, &_port, sizeof(DWORD), DPNA_DATATYPE_DWORD)))
goto fail;
// set adapter (if any)
if(guid_adapter)
{
if(FAILED(dp_address->AddComponent(DPNA_KEY_DEVICE, guid_adapter, sizeof(GUID), DPNA_DATATYPE_GUID)))
goto fail;
}
// record the session name and password
strcpy(_session_name, session_name);
mbstowcs(w_session_name, session_name, MAX_PATH);
if(session_pwd)
{
strcpy(_session_pwd, session_pwd);
mbstowcs(w_session_pwd, session_pwd, MAX_PATH);
}
// setup the application description structure
ZeroMemory(&app_desc, sizeof(DPN_APPLICATION_DESC));
app_desc.dwSize = sizeof(DPN_APPLICATION_DESC);
app_desc.dwFlags = DPNSESSION_CLIENT_SERVER;
app_desc.guidApplication = g_app_guid;
app_desc.pwszSessionName = w_session_name;
if(session_pwd)
{
app_desc.pwszPassword = w_session_pwd;
app_desc.dwFlags |= DPNSESSION_REQUIREPASSWORD;
}
_max_players = max_players;
app_desc.dwMaxPlayers = max_players;
// start the hosting
if(FAILED(_server->Host(&app_desc, &dp_address, 1, NULL, NULL, NULL, 0)))
goto fail;
dp_address->Release();
_is_connected = TRUE;
return TRUE;
fail:
dp_address->Release();
return FALSE;
}
//---------------------------------------------------------------------------------
// Check whether server is hosting now.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::is_connected()
{
return _is_connected;
}
//---------------------------------------------------------------------------------
// Send data to client.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::send_data(DPNID player_id, void* data, ulong size, ulong flags)
{
// error checking
if(_server == NULL || size == 0)
return FALSE;
DPNHANDLE async_handle;
DPN_BUFFER_DESC buf_desc;
buf_desc.dwBufferSize = size;
buf_desc.pBufferData = (BYTE*) data;
if(FAILED(_server->SendTo(player_id, &buf_desc, 1, 0, NULL, &async_handle, flags)))
return FALSE;
return TRUE;
}
//---------------------------------------------------------------------------------
// Send string to client.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::send_text(DPNID player_id, char* text, ulong flags)
{
// error checking
if(_server == NULL || text == NULL)
return FALSE;
return send_data(player_id, text, (ulong)strlen(text)+1, flags);
}
//---------------------------------------------------------------------------------
// Disconnect specified player.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::disconnect_player(long player_id)
{
// error checking
if(_server == NULL)
return FALSE;
// try to disconnect the specified player
if(FAILED(_server->DestroyClient(player_id, NULL, 0, 0)))
return FALSE;
return TRUE;
}
//---------------------------------------------------------------------------------
// Get ip address, include server and client ip address.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::get_ip(char* ip, ulong player_id)
{
// get host ip address if player_id == 0
if(player_id == 0)
{
WSADATA wsa_data;
// initiates use of ws2_32.dll by a process
if(WSAStartup(MAKEWORD(1, 0), &wsa_data))
return FALSE;
char local_name[MAX_PATH];
// retrieves the standard host name for the local computer
gethostname(local_name, MAX_PATH);
// store information about a given host, such as host name, ip address, and so forth.
HOSTENT* host_ent;
// retrieves host information corresponding to a host name from a host database
if((host_ent = gethostbyname(local_name)) == NULL)
{
// terminates use of the ws2_32.dll
WSACleanup();
return FALSE;
}
// get localip
char* local_ip = inet_ntoa(*(in_addr*)host_ent->h_addr_list[0]);
WSACleanup();
if(local_ip == NULL)
return FALSE;
strcpy(ip, local_ip);
return TRUE;
}
if(_server == NULL || !_is_connected)
return FALSE;
IDirectPlay8Address* dp_address;
// retrieve the player information
if(FAILED(_server->GetClientAddress((DPNID)player_id, &dp_address, 0)))
return FALSE;
DWORD size = MAX_PATH;
DWORD flags = DPNA_DATATYPE_STRING;
WCHAR client_address[MAX_PATH];
// retrieves information on the component at the specified key
if(FAILED(dp_address->GetComponentByName(DPNA_KEY_HOSTNAME, client_address, &size, &flags)))
{
dp_address->Release();
return FALSE;
}
wcstombs(ip, client_address, MAX_PATH);
dp_address->Release();
return TRUE;
}
//---------------------------------------------------------------------------------
// Get player name.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::get_name(char* name, ulong player_id)
{
if(_server == NULL)
return FALSE;
DPN_PLAYER_INFO* player_info = NULL;
DWORD size = 0;
// retrieves the client information set for the specified client
HRESULT rv = _server->GetClientInfo(player_id, player_info, &size, 0);
if(FAILED(rv) && rv != DPNERR_BUFFERTOOSMALL)
return FALSE;
player_info = (DPN_PLAYER_INFO*) new char[size];
player_info->dwSize = sizeof(DPN_PLAYER_INFO);
if(FAILED(_server->GetClientInfo(player_id, player_info, &size, 0)))
{
delete[] player_info;
return FALSE;
}
wcstombs(name, player_info->pwszName, MAX_PATH);
delete[] player_info;
return TRUE;
}
//---------------------------------------------------------------------------------
// Return port of server.
//---------------------------------------------------------------------------------
long NETWORK_SERVER::get_port()
{
return _port;
}
//---------------------------------------------------------------------------------
// Get session name.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::get_session_name(char* session_name)
{
if(session_name == NULL)
return FALSE;
strcpy(session_name, _session_name);
return TRUE;
}
//---------------------------------------------------------------------------------
// Get session password.
//---------------------------------------------------------------------------------
BOOL NETWORK_SERVER::get_session_pwd(char* session_pwd)
{
if(session_pwd == NULL)
return FALSE;
strcpy(session_pwd, _session_pwd);
return TRUE;
}
//---------------------------------------------------------------------------------
// Return max players permitted to login.
//---------------------------------------------------------------------------------
long NETWORK_SERVER::get_max_players()
{
return _max_players;
}
//---------------------------------------------------------------------------------
// Return current player number.
//---------------------------------------------------------------------------------
long NETWORK_SERVER::get_cur_players_num()
{
return _cur_players_num;
}
//---------------------------------------------------------------------------------
// Callback function to handler message for server.
//---------------------------------------------------------------------------------
HRESULT WINAPI NETWORK_SERVER::_network_msg_handler(PVOID user_context, DWORD msg_id, PVOID msg_buffer)
{
NETWORK_SERVER* server;
if((server = (NETWORK_SERVER*) user_context) == NULL)
return E_FAIL;
// pass message to user-defined function
switch(msg_id)
{
case DPN_MSGID_ADD_PLAYER_TO_GROUP:
if(server->_add_player_to_group((DPNMSG_ADD_PLAYER_TO_GROUP*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_ASYNC_OP_COMPLETE:
if(server->_async_op_complete((DPNMSG_ASYNC_OP_COMPLETE*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_CLIENT_INFO:
if(server->_client_info((DPNMSG_CLIENT_INFO*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_CONNECT_COMPLETE:
if(server->_connect_complete((DPNMSG_CONNECT_COMPLETE*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_CREATE_GROUP:
if(server->_create_group((DPNMSG_CREATE_GROUP*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_CREATE_PLAYER:
if(server->_create_player((DPNMSG_CREATE_PLAYER*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_DESTROY_GROUP:
if(server->_destroy_group((DPNMSG_DESTROY_GROUP*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_DESTROY_PLAYER:
if(server->_destroy_player((DPNMSG_DESTROY_PLAYER*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_ENUM_HOSTS_QUERY:
if(server->_enum_hosts_query((DPNMSG_ENUM_HOSTS_QUERY*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_ENUM_HOSTS_RESPONSE:
if(server->_enum_hosts_response((DPNMSG_ENUM_HOSTS_RESPONSE*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_GROUP_INFO:
if(server->_group_info((DPNMSG_GROUP_INFO*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_HOST_MIGRATE:
if(server->_host_migrate((DPNMSG_HOST_MIGRATE*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_INDICATE_CONNECT:
if(server->_indicate_connect((DPNMSG_INDICATE_CONNECT*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_INDICATED_CONNECT_ABORTED:
if(server->_indicated_connect_aborted((DPNMSG_INDICATED_CONNECT_ABORTED*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_PEER_INFO:
if(server->_peer_info((DPNMSG_PEER_INFO*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_RECEIVE:
if(server->_receive((DPNMSG_RECEIVE*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_REMOVE_PLAYER_FROM_GROUP:
if(server->_remove_player_from_group((DPNMSG_REMOVE_PLAYER_FROM_GROUP*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_RETURN_BUFFER:
if(server->_return_buffer((DPNMSG_RETURN_BUFFER*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_SEND_COMPLETE:
if(server->_send_complete((DPNMSG_SEND_COMPLETE*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_SERVER_INFO:
if(server->_server_info((DPNMSG_SERVER_INFO*) msg_buffer))
return S_OK;
break;
case DPN_MSGID_TERMINATE_SESSION:
if(server->_terminate_session((DPNMSG_TERMINATE_SESSION*) msg_buffer))
return S_OK;
break;
}
return E_FAIL;
}
要使用NETWORK_SERVER
類，需要將NETWORK_SERVER
類作為基類派生出自己的類。這樣做的原因在于必須重載網(wǎng)絡處理函數(shù)以滿足自己具體的功能需要，NETWORK_SERVER
類中包含了每條網(wǎng)絡消息，因此派生出來的類絕不會丟失重要的消息。
要主持游戲會話，需要適配器GUID、會話名稱、可選的密碼以及允許的玩家最大數(shù)目（使用0表示不限制玩家數(shù)目）。當調(diào)用NETWORK_SERVER::host函數(shù)時，DirectPlay就會初始化連接并將控制權(quán)返回給使用者。現(xiàn)在，假設有消息發(fā)過來，那么就應該接收發(fā)送過來的消息并在合適的時候處理它們。創(chuàng)建的每個消息處理函數(shù)，如果返回TRUE就表明消息被成功處理，F(xiàn)ALSE表明有錯誤發(fā)生。
接著我們編寫一段代碼來測試NETWORK_SERVER類：
/********************************************************************************
PURPOSE:
Test for class NETWORK_SERVER.
********************************************************************************/
#include "Core_Global.h"
#define HOST_PORT 12345
class SERVER : public NETWORK_SERVER
{
private:
virtual BOOL _receive(DPNMSG_RECEIVE* msg)
{
MessageBox(NULL, LPCSTR(msg->pReceiveData), "client message", MB_OK);
// send data back to client
return send_data(msg->dpnidSender, msg->pReceiveData, msg->dwReceiveDataSize, DPNSEND_GUARANTEED);
}
};
class APP : public APPLICATION
{
public:
BOOL init()
{
if(! _adapter.init())
return FALSE;
// get first adapter guid
GUID* guid_adapter = _adapter.get_guid(0);
if(! _server.init())
return FALSE;
if(! _server.host(guid_adapter, HOST_PORT, "test_session"))
return FALSE;
return TRUE;
}
BOOL frame()
{
Sleep(300);
return TRUE;
}
BOOL shutdown()
{
return TRUE;
}
private:
SERVER _server;
NETWORK_ADAPTER _adapter;
};
int WINAPI WinMain(HINSTANCE inst, HINSTANCE, LPSTR cmd_line, int cmd_show)
{
APP app;
return app.run();
}