飞鸽传书源码分析三-网络
陶裕
转载请注明出处：http://blog.csdn.net/mxway/article/details/44195099
本文是在飞鸽传书2.06源码基础之上进行分析的。
一、网络的初始化
飞鸽传书主窗口对应的类TMainWin的构造函数中有如下的代码
cfg = new Cfg(nicAddr, portNo = _portNo);
if ((msgMng = new MsgMng(nicAddr, portNo, cfg))->GetStatus() == FALSE)
{
::ExitProcess(0xffffffff);
return;
}在MsgMng类的构造函数中调用WSockInit。
MsgMng::MsgMng(ULONG nicAddr, int portNo, Cfg *_cfg)
{
...
local.addr = nicAddr;
local.portNo = htons(portNo);
...
if (WSockInit(cfg ? TRUE : FALSE) == FALSE)
return;
...
}BOOL MsgMng::WSockInit(BOOL recv_flg)
{
WSADATA wsaData;
if (::WSAStartup(0x0101, &wsaData) != 0)
return GetSockErrorMsg("WSAStart()"), FALSE;
if ((udp_sd = ::socket(AF_INET, SOCK_DGRAM, 0)) == INVALID_SOCKET)
return GetSockErrorMsg("Please setup TCP/IP(controlpanel->network)\r\n"), FALSE;
if (recv_flg != TRUE)
return TRUE;
if ((tcp_sd = ::socket(AF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET)
return GetSockErrorMsg("Please setup2 TCP/IP(controlpanel->network)\r\n"), FALSE;
struct sockaddr_in addr;
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = local.addr;
addr.sin_port = local.portNo;
if (::bind(udp_sd, (LPSOCKADDR)&addr, sizeof(addr)) != 0)
return GetSockErrorMsg("bind()"), FALSE;
if (::bind(tcp_sd, (LPSOCKADDR)&addr, sizeof(addr)) != 0)
{
::closesocket(tcp_sd);
tcp_sd = INVALID_SOCKET;
GetSockErrorMsg("bind(tcp) error. Can't support file attach");
}
BOOL flg = TRUE; // Non Block
if (::ioctlsocket(udp_sd, FIONBIO, (unsigned long *)&flg) != 0)
return GetSockErrorMsg("ioctlsocket(nonblock)"), FALSE;
if (IsAvailableTCP() && ::ioctlsocket(tcp_sd, FIONBIO, (unsigned long *)&flg) != 0)
return GetSockErrorMsg("ioctlsocket tcp(nonblock)"), FALSE;
flg = TRUE; // allow broadcast
if (::setsockopt(udp_sd, SOL_SOCKET, SO_BROADCAST, (char *)&flg, sizeof(flg)) != 0)
return GetSockErrorMsg("setsockopt(broadcast)"), FALSE;
int buf_size = MAX_SOCKBUF, buf_minsize = MAX_SOCKBUF / 2; // UDP
if (::setsockopt(udp_sd, SOL_SOCKET, SO_SNDBUF, (char *)&buf_size, sizeof(int)) != 0
&& ::setsockopt(udp_sd, SOL_SOCKET, SO_SNDBUF, (char *)&buf_minsize, sizeof(int)) != 0)
GetSockErrorMsg("setsockopt(sendbuf)");
buf_size = MAX_SOCKBUF, buf_minsize = MAX_SOCKBUF / 2;
if (::setsockopt(udp_sd, SOL_SOCKET, SO_RCVBUF, (char *)&buf_size, sizeof(int)) != 0
&& ::setsockopt(udp_sd, SOL_SOCKET, SO_RCVBUF, (char *)&buf_minsize, sizeof(int)) != 0)
GetSockErrorMsg("setsockopt(recvbuf)");
flg = TRUE; // REUSE ADDR
if (IsAvailableTCP() && ::setsockopt(tcp_sd, SOL_SOCKET, SO_REUSEADDR, (char *)&flg, sizeof(flg)) != 0)
GetSockErrorMsg("setsockopt tcp(reuseaddr)");
if (IsAvailableTCP() && ::listen(tcp_sd, 5) != 0)
return FALSE;
return TRUE;
}在WSockInit中初始化进行网络编程所要用的dll，并设置了tcp服务及udp所占用的端口号，并设置udp及tcp的socket为非阻塞模式。tcp及udp服务所占的端口是由TMainWin的构造函数传到MsgMng的构造函数中的。在TMainWin的构造函数传给MsgMng的端号来自TMainWin的构造函数。回到Ipmsg.cpp的TMsgApp::InitWindow函数中（具体可参考前面的飞鸽传书源码分析文章）
void TMsgApp::InitWindow(void)
{
...
int port_no = atoi(cmdLine);
if (port_no == 0)
port_no = IPMSG_DEFAULT_PORT;
...
mainWnd = new TMainWin(nicAddr, port_no);mainWnd->Create(class_name, IP_MSG, WS_OVERLAPPEDWINDOW | (IsNewShell() ? WS_MINIMIZE : 0));...}#define IPMSG_DEFAULT_PORT 0x0979
飞鸽传书默认服务的端口是十六进制979也就是十进制的2425。
二、网络非阻塞模式
在windows下实现socket有多种方式，飞鸽传书使用的是将网络事件以消息方式发送给窗口句柄，而处理网络事件的窗口就是TMainWin。在IPmsg.cpp的InitWindow调用完mainWnd->Create(class_name, IP_MSG, WS_OVERLAPPEDWINDOW | (IsNewShell() ? WS_MINIMIZE : 0));后会执行TMainWin的EvCreate(调用过程详解见第二篇的消息机制)
BOOL TMainWin::EvCreate(LPARAM lParam)
{
...
msgMng->AsyncSelectRegist(hWnd);
...
if (msgMng->GetStatus())
EntryHost();
}
BOOL MsgMng::AsyncSelectRegist(HWND hWnd)
{
if (hAsyncWnd == 0)
hAsyncWnd = hWnd;
if (::WSAAsyncSelect(udp_sd, hWnd, WM_UDPEVENT, FD_READ) == SOCKET_ERROR)
return FALSE;
if (::WSAAsyncSelect(tcp_sd, hWnd, WM_TCPEVENT, FD_ACCEPT|FD_CLOSE) == SOCKET_ERROR)
return FALSE;
return TRUE;
}BOOL TMainWin::EventUser(UINT uMsg, WPARAM wParam, LPARAM lParam)
{
...
case WM_UDPEVENT:
UdpEvent(lParam);
return TRUE;
...
}飞鸽传书是工作是局域网的程序，当有新的设备使用飞鸽传书程序时，会自动通知到其它已经在线的用户，将自己显示到其它用户的列表中。
调用完msgMng->AsyncSelectRegist(hWnd);将网络事件与窗口句柄勾搭上之后，程序就会对局域网进行广播，告诉其它人自己打开了飞鸽传书程序。
void TMainWin::EntryHost(void)
{
...
BroadcastEntry(IPMSG_BR_ENTRY);
...
}void TMainWin::BroadcastEntry(ULONG mode)
{
msgMng->Send((ULONG)~0, htons(portNo), host_status, GetNickNameEx(), cfg->GroupNameStr);
}
类似资料：