/********************************************************* * * This source code is part of the Carnegie Mellon Robot * Navigation Toolkit (CARMEN) * * CARMEN Copyright (c) 2002 Michael Montemerlo, Nicholas * Roy, Sebastian Thrun, Dirk Haehnel, Cyrill Stachniss, * and Jared Glover * * CARMEN is free software; you can redistribute it and/or  * modify it under the terms of the GNU General Public  * License as published by the Free Software Foundation;  * either version 2 of the License, or (at your option) * any later version. * * CARMEN is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR * PURPOSE.  See the GNU General Public License for more  * details. * * You should have received a copy of the GNU General  * Public License along with CARMEN; if not, write to the * Free Software Foundation, Inc., 59 Temple Place,  * Suite 330, Boston, MA  02111-1307 USA * ********************************************************/#include <stdio.h>#include <errno.h>#include <stdlib.h>#include <string.h>#include <termios.h>#include <unistd.h>#include <sys/types.h>#include <sys/stat.h>#include <fcntl.h>#include <pthread.h>//#include <wait.h>#include <ctype.h>#include <netinet/tcp.h>#include <netinet/in.h>#include <netdb.h>#include "orc.h"typedef struct {	char *hostname;	int port;} tcpprovider_t;static int tcp_connect(orc_comms_impl_t *impl){	tcpprovider_t *t = (tcpprovider_t*) impl->_p;	struct hostent *host;	struct sockaddr_in sa;	int thesocket;	/* let's find out about this host */	host = gethostbyname(t->hostname);	if (host==NULL)	{		//      perror(hostname);		return -1;	}	/* create the socket */	thesocket=socket(AF_INET,SOCK_STREAM,0);	/* fill in the fields */	bzero(&sa,sizeof(sa));	sa.sin_family=AF_INET;	sa.sin_port=htons(0);	sa.sin_addr.s_addr=htonl(INADDR_ANY);	/* bind it to the port */	if (bind (thesocket, (struct sockaddr *) &sa, sizeof (sa)) <0)	{		close(thesocket);		return -1;	}	sa.sin_port=htons(t->port);	sa.sin_addr=*(struct in_addr *) host->h_addr;	if (connect(thesocket, (struct sockaddr *) &sa, sizeof (sa)))	{		if (errno!=EINPROGRESS)		{			close(thesocket);			return -1;		}	}	// prevent "broken pipe" signals.	signal(SIGPIPE, SIG_IGN);	// disable nagle algorithm	int n=1;	if (setsockopt (thesocket, IPPROTO_TCP, TCP_NODELAY, 			(char *) &n, sizeof(n))<0)	{		perror("could not setsockopt");		close(thesocket);		return -1;	}	return thesocket;}static void tcp_disconnect(orc_comms_impl_t *impl __attribute__ ((unused)), int fd){	close(fd);	return;}orc_comms_impl_t *orc_tcpprovider_create(char *hostname, int port){	orc_comms_impl_t *impl = (orc_comms_impl_t*) calloc(sizeof(orc_comms_impl_t), 1);		tcpprovider_t *t = (tcpprovider_t*) calloc(sizeof(tcpprovider_t), 1);	t->hostname = strdup(hostname);	t->port = port;		impl->connect = tcp_connect;	impl->disconnect = tcp_disconnect;	impl->_p = t;	return impl;}