winsock broadcast 예제 소스

대략 winsock 으로 braodcast 하는 c++ 소스입니다.

// Broadcaster.h #ifndef _BROADCASTER_H_ #define _BROADCASTER_H_ class Broadcaster { public: Broadcaster(uint16 port) : _handle(INVALID_SOCKET), _port(port) {} ~Broadcaster() {close();} public: bool open(); void close(); void send(const char *message, size_t size); bool isOpen() const {return (_handle != INVALID_SOCKET);} private: SOCKET _handle; uint16 _port; struct sockaddr_in _broadAddr; // SOCKADDR_IN _broadAddr; }; #endif //_BROADCASTER_H_

// Broadcaster.cpp #include "Broadcaster.h" bool Broadcaster::open() { WSADATA wsaData; int32 state, so_broadcast = 1; char name[256] = "localhost"; // getting own IP address from "localhost" char* address; struct hostent* pHostEnt; // HOSTENT* pHostEnt; struct in_addr in; // IN_ADDR in; DWORD myIP, subnet, temp1, temp2; if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) { trace("WSAStartup() error"); return false; } if ((_handle = socket(PF_INET, SOCK_DGRAM, 0)) == INVALID_SOCKET) { trace("socket() error\n"); return false; } gethostname(name, 256); trace("host name : %s\n", name); pHostEnt = gethostbyname(name); in.s_addr =((struct in_addr*)pHostEnt->h_addr)->s_addr; address = inet_ntoa(in); // printf("IP Addr : %s\n", address); myIP = inet_addr(address); subnet = inet_addr("255.255.255.0"); temp1 = myIP & subnet; temp2 = subnet ^ 0xFFFFFFFF; memset(&_broadAddr, 0, sizeof(_broadAddr)); _broadAddr.sin_family = AF_INET; _broadAddr.sin_port = htons(_port); _broadAddr.sin_addr.s_addr = temp1 + temp2; // set a socket for broadcast state = setsockopt(_handle, SOL_SOCKET, SO_BROADCAST, (char*)&so_broadcast, sizeof(so_broadcast)); if (state == SOCKET_ERROR) { trace("setsockopt() error\n"); } return true; } void Broadcaster::close() { if (isOpen()) { closesocket(_handle); WSACleanup(); _handle = INVALID_SOCKET; } } void Broadcaster::send(const char *message, size_t size) { if (!isOpen()) { trace("socket not open\n"); return; } sendto(_handle, message, size, 0, (SOCKADDR*)&_broadAddr, sizeof(_broadAddr)); }

아래는 테스트용 reader 코드

// UDP Broadcast Client (Receiver) #include "stdafx.h" #include <stdio.h> #include <stdlib.h> #include <string.h> #include <winsock2.h> #pragma comment(lib, "ws2_32.lib") #define BROAD_CAST_PORT 4970 #define BUFSIZE 32 void ErrorHandling(char *message); int main(int argc, char **argv) { WSADATA wsaData; SOCKET hRecvSock; SOCKADDR_IN addr; int strLen; char buf[BUFSIZE]; if(WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) /* Load Winsock 2.2 DLL */ ErrorHandling("WSAStartup() error!"); hRecvSock=socket(PF_INET, SOCK_DGRAM, 0); /*ºê·Îµåij½ºÆ®¸¦ À§ÇÑ UDP¼ÒÄÏ »ý¼º */ if(hRecvSock == INVALID_SOCKET) ErrorHandling("socket() error"); memset(&addr, 0, sizeof(addr)); addr.sin_family=AF_INET; addr.sin_addr.s_addr=htonl(INADDR_ANY); addr.sin_port=htons(BROAD_CAST_PORT); /* ºê·Îµåij½ºÆ® port ¼³Á¤ */ if(bind(hRecvSock, (SOCKADDR*) &addr, sizeof(addr))==SOCKET_ERROR) ErrorHandling("bind() error"); while(1){ strLen=recvfrom(hRecvSock, buf, BUFSIZE-1, 0, NULL, 0); if(strLen<0) break; buf[strLen]=0; fputs(buf, stdout); } closesocket(hRecvSock); WSACleanup(); return 0; } void ErrorHandling(char *message) { fputs(message, stderr); fputc('\n', stderr); exit(1); }

references : 

http://www.devpia.com/MAEUL/Contents/Detail.aspx?BoardID=51&MAEULNo=20&no=7103&ref=7103
http://blog.daum.net/jjiyong/12873890