static void create()
{
::create();
set_short_desc("Entrance");
set_long_desc("A small, cramped room, roughly hewn from rock with little " +
"eye for detail.\n");
add_neighbour("workroom",
"east", 0,
1, 1,
"A small room is visible through a doorway to the west.",
"to the west");
}
int main(int argc, char **argv) {
/* command line arguments variables */
char *smewsBinaryPath = NULL;
int nNodes = DEFAULT_NNODES;
double nodeRange = DEFAULT_NODE_RANGE;
double lossRate = DEFAULT_LOSS_RATE;
/* misc. locals... */
int i;
int j;
int ret;
int nRead;
int nfds;
int tun_fd;
int socket_fd;
fd_set fdset;
char tmpstr[64];
char *cptr;
struct sockaddr_in sockaddr;
/* arguments parsing */
if(argc == 1)
usage();
opterr = 0;
while ((j = getopt (argc, argv, "hb:n:r:l:")) != -1) {
switch (j) {
case 'h':
usage();
break;
case 'b':
smewsBinaryPath = optarg;
break;
case 'n':
nNodes = strtol(optarg, &cptr, 10);
ensure(!*cptr && nNodes > 0,"Option -n requires a positive integer as argument.\n");
break;
case 'r':
nodeRange = strtod(optarg, &cptr);
ensure(!*cptr && nodeRange > 0 && nodeRange <=1,"Option -r requires a float in ]0-1] as argument.\n");
break;
case 'l':
lossRate = strtod(optarg, &cptr);
ensure(!*cptr && lossRate >= 0 && lossRate <=1,"Option -r requires a float in [0-1] as argument.\n");
break;
case '?':
if(isprint (optopt))
sprintf(tmpstr,"Unknown option `-%c'.\n", optopt);
else
sprintf(tmpstr,"Unknown option character `0x%x'.\n",optopt);
ensure(0,tmpstr);
default:
ensure(0,"An error occured when parsing the arguments.\n");
}
}
if(optind != argc) {
sprintf(tmpstr,"Invalid argument `%s'\n", argv[optind]);
ensure(0,tmpstr);
}
ensure(smewsBinaryPath != NULL,"Option -b is required.\n");
/* print the current configuration */
printf("Configuring the simulator...\n");
printf("Smews binary path: %s\n",smewsBinaryPath);
printf("Amount of nodes: %d\n",nNodes);
printf("Nodes range: %f\n",nodeRange);
printf("Loss rate: %f\n",lossRate);
/* catch the 16 first signals signals */
for(i=1; i<16; i++)
signal(i, &cleanup);
/* host socket creation */
socket_fd = socket(AF_INET,SOCK_DGRAM,0);
check(socket_fd != -1,"socket() error");
sockaddr.sin_family = AF_INET;
sockaddr.sin_port = htons(1024);
sockaddr.sin_addr.s_addr = inet_addr("127.0.0.1");
memset(&sockaddr.sin_zero,0,8);
ret=bind(socket_fd,(struct sockaddr*)&sockaddr,sizeof(sockaddr));
check(ret != -1,"bind() error");
/* Smews processes and nodes creation */
nodes = (struct node_s *)malloc(nNodes*sizeof(struct node_s));
check(nodes != NULL,"malloc() error");
srand(time(NULL));
for(i=0; i<nNodes; i++) {
nodes[i].first_neighbour = NULL;
nodes[i].nodeN = i;
/* set coordinates for the node i */
do {
nodes[i].x = rand()/(float)RAND_MAX;
nodes[i].y = rand()/(float)RAND_MAX;
for(j=0; j<i; j++) {
/* set neighbourhoud */
if(ABS_DIST(nodes[i],nodes[j]) <= nodeRange) {
add_neighbour(&nodes[i],&nodes[j]);
add_neighbour(&nodes[j],&nodes[i]);
}
}
/* ensures that the graph is connected */
} while (i!=0 && !nodes[i].first_neighbour);
/* new Smews process creation */
sprintf(tmpstr,"%d",i);
setenv("SMEWS_ID",tmpstr,1);
if(!vfork()) {
execl(smewsBinaryPath,"",NULL);
perror("execl() error");
cleanup(2);
}
}
/* TUN interface creation */
struct ifreq ifr;
tun_fd = open(DEVTUN, O_RDWR);
check(tun_fd != -1,"tun open() error");
memset(&ifr, 0, sizeof(ifr));
ifr.ifr_flags = IFF_TUN;
ret = ioctl(tun_fd, TUNSETIFF, (void *) &ifr);
check(ret >= 0,"tun ioctl error");
/* TUN attachement to an IP address */
snprintf((char*)tmpstr, BUFSIZE, "ifconfig %s 192.168.0.0 pointopoint 192.168.1.0 mtu 1500",ifr.ifr_name);
ret = system((char*)tmpstr);
check(ret != -1,"system() error when setting ifconfig");
/* main loop */
printf("Simulation is launched...\n");
nfds = MAX(tun_fd,socket_fd)+1;
FD_ZERO(&fdset);
while(1) {
FD_SET(tun_fd, &fdset);
FD_SET(socket_fd, &fdset);
ret = select(nfds, &fdset, NULL, NULL, NULL);
check(ret != -1,"select() error");
/* wait for something to read on tun_fd or socket_fd */
if(ret) {
if(FD_ISSET(tun_fd, &fdset)) {
/* something has been received on tun_fd, we forward it to the reachable node */
nRead = read(tun_fd, (void *)buffer, BUFSIZE);
check(nRead != -1,"read() error");
if(!loss_occurs(0,1,lossRate)) {
sockaddr.sin_port = htons(1025);
ret = sendto(socket_fd,buffer,nRead,0,(struct sockaddr*)&sockaddr,sizeof(sockaddr));
check(ret != -1,"sendto() error");
}
}
if(FD_ISSET(socket_fd, &fdset)) {
/* something has been received on socket_fd */
int addrLen;
int emitterN;
nRead = recvfrom(socket_fd,buffer,BUFSIZE,0,(struct sockaddr*)&sockaddr,&addrLen);
check(nRead != -1,"recvfrom() error");
emitterN = ntohs(sockaddr.sin_port) - (1025);
if(emitterN >= 0 && emitterN < nNodes) {
/* send the datagram to all the neighbours of the emitter */
struct neighbour_s *curr_neighbour = nodes[emitterN].first_neighbour;
while(curr_neighbour) {
if(!loss_occurs(emitterN,curr_neighbour->node->nodeN,lossRate)) {
sockaddr.sin_port = htons(1025 + curr_neighbour->node->nodeN);
ret = sendto(socket_fd,buffer,nRead,0,(struct sockaddr*)&sockaddr,sizeof(sockaddr));
check(ret != -1,"sendto() error");
}
curr_neighbour = curr_neighbour->next;
}
/* if the emitter is the reachable node, send the datagram on the TUN interface */
if(emitterN == 0) {
if(!loss_occurs(emitterN,0,lossRate)) {
ret = write(tun_fd, buffer_shadow, nRead+4);
check(ret != -1,"write() error");
}
}
}
}
}
}
return 0;
}
