hb_server.c

一个很好的unix网络编程框架

#include "etcp.h"
#include "heartbeat.h"

int main( int argc, char **argv )
{
	fd_set allfd;
	fd_set readfd;
	msg_t msg;
	struct timeval tv;
	SOCKET s;
	SOCKET s1;
	int rc;
	int missed_heartbeats = 0;
	int cnt = sizeof( msg );

	INIT();
	s = tcp_server( NULL, argv[ 1 ] );
	s1 = accept( s, NULL, NULL );
	if ( !isvalidsock( s1 ) )
		error( 1, errno, "accept failed" );
	tv.tv_sec = T1 + T2;
	tv.tv_usec = 0;
	FD_ZERO( &allfd );
	FD_SET( s1, &allfd );
	for ( ;; )
	{
		readfd = allfd;
		rc = select( s1 + 1, &readfd, NULL, NULL, &tv );
		if ( rc < 0 )
			error( 1, errno, "select failure" );
		if ( rc == 0 )		/* timed out */
		{
			if ( ++missed_heartbeats > 3 )
				error( 1, 0, "connection dead\n" );
			error( 0, 0, "missed heartbeat #%d\n",
				missed_heartbeats );
			tv.tv_sec = T2;
			continue;
		}
		if ( !FD_ISSET( s1, &readfd ) )
			error( 1, 0, "select returned invalid socket\n" );
		rc = recv( s1, ( char * )&msg + sizeof( msg ) - cnt,
			cnt, 0 );
		if ( rc == 0 )
			error( 1, 0, "client terminated\n" );
		if ( rc < 0 )
			error( 1, errno, "recv failure" );
		missed_heartbeats = 0;
		tv.tv_sec = T1 + T2;
		cnt -= rc;				/* in-line readn */
		if ( cnt > 0 )
			continue;
		cnt = sizeof( msg );
		switch ( ntohl( msg.type ) )
		{
			case MSG_TYPE1 :
				/* process type1 message */
				break;

			case MSG_TYPE2 :
				/* process type2 message */
				break;

			case MSG_HEARTBEAT :
				rc = send( s1, ( char * )&msg, sizeof( msg ), 0 );
				if ( rc < 0 )
					error( 1, errno, "send failure" );
				break;

			default :
				error( 1, 0, "unknown message type (%d)\n",
					ntohl( msg.type ) );
		}
	}
	EXIT( 0 );
}