/* DESC: This script reads messages coming from the serial port and forwards them via TCP to remote hosts (and vice versa).
* Copyright (C) 2014 NetModule AG, Switzerland
*
* Usage: usage: serial-tcp-broadcast.are <remote-ip-1> <remote-ip-2> .... <remote-ip-n>
* Version: 2.0
*
*/
/*
* Options to configure by user
*/
/* Serial Baud Rate 9600, 19200, 38400, 57600, 115200 */
SER_SPEED = 115200;
/* number of data bits (5, 6, 7, 8) */
SER_DATABIT = 8;
/* number of stop bits (1, 2) */
SER_STOPBIT = 1;
/* parity (0=no parity, 1=odd parity, 2=even parity) */
SER_PARITY = 0;
/* flow control (0=none, 1=xon/xoff, 2=hardware) */
SER_FLOW = 0;
/* name of the Serial Interface */
DEV = "SERIAL1";
DEVIDX = ((int) substr(DEV, 6, 1)) - 1;
/* TCP Options */
/* number of retries when connecting to a slave */
RETRY = 3;
/* the interval in seconds for each retry */
RETRY_INTERVAL = 3;
/* recovery interval after slave got disconnected or retries were unsuccessful */
RECOVER_INTERVAL = 120;
/*
* Only changed things below if you know what you are doing
*/
POLL_TIMEOUT = 10; /* seconds */
REMOTE_PORT =2000; /* port of the remote serial slaves (default 2000) */
/* slave template */
template slave
{
hostname = "";
fd = -1;
state = "down";
since = 0;
void slave(string remotehost)
{
nb_syslog("Creating slave %s",remotehost);
if (strlen(remotehost) > 0) {
this.hostname = remotehost;
} else {
nb_syslog("ERROR: no hostname defined, slave could not be created");
}
}
int jiffy()
{
sys = sysinfo();
u = struct_get(sys, "uptime");
if (is_void(u) || u < 1) {
return 0;
} else {
return u;
}
}
int connect() {
if (this.fd > -1) {
close(this.fd);
this.fd = -1;
}
nb_syslog("Connecting to %s", this.hostname);
/* open TCP socket */
sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,1);
setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,1);
setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,5);
setsockopt(sock, SOL_TCP, TCP_KEEPCNT,5);
if (sock < 0) {
nb_syslog("ERROR: unable to open socket");
}
for (i = 0; i < RETRY; i++) {
if (connect(sock, this.hostname, REMOTE_PORT) < 0){
nb_syslog("ERROR: could not connect to %s:%d", this.hostname, REMOTE_PORT);
nb_syslog("Retrying to connect (trial #%i, waiting %s sec)", i, RETRY_INTERVAL);
sleep(RETRY_INTERVAL);
} else {
nb_syslog("TCP connection established to host %s:%d", this.hostname, REMOTE_PORT);
this.fd = sock;
this.state = "up";
return 0;
}
}
nb_syslog("ERROR: max. retries reached for %s, giving up", this.hostname);
this.since = this.jiffy();
this.state = "down";
close(this.fd);
this.fd = -1;
return -1;
}
int disconnect() {
if (this.fd > -1) {
close(this.fd);
this.fd = -1;
}
this.state = "down";
this.since = this.jiffy();
nb_syslog("Disconnected host %s", this.hostname);
return 0;
}
} /* endof template slave */
int start_serial()
{
/* check serial port config */
status = nb_config_get(sprintf("serial.%d.status", DEVIDX));
if (status != "2") {
nb_syslog("ERROR: serial port %d is not enabled for us", DEVIDX);
exit(1);
}
/* set attributes */
rc = nb_serial_setattr(DEV, SER_SPEED, SER_DATABIT, SER_STOPBIT, SER_PARITY, SER_FLOW);
if (rc != 0) {
nb_syslog("ERROR: unable to set serial attributes (rc %d)", rc);
exit(1);
}
/* open serial port */
fd = nb_serial_open(DEV);
if (fd < 0) {
nb_syslog("ERROR: unable to open serial device (%s)", DEV);
exit(1);
}
return fd;
}
int stop_serial()
{
if (fd > -1) {
close(fd);
fd = -1;
}
return 0;
}
void usage()
{
nb_syslog("usage: serial-tcp-broadcast.are <remote-ip-1> <remote-ip-2> .... <remote-ip-n>");
exit(1);
}
/* ------------------------ main ------------------------------- */
if (strlen(argv[1]) == 0) {
nb_syslog("ERROR: no remote host specified");
usage();
}
/* create slaves */
nb_syslog("creating slaves");
for (i = 1; i < argc; i++) {
slaves[i-1] = new slave(argv[i]);
}
/* connect slave */
for (i = 0; i < length(slaves); i++) {
nb_syslog("connecting slave %d", i);
rc = slaves[i].connect();
if (rc < 0) {
nb_syslog("ERROR: could not connect %s", slaves[i].hostname);
}
}
nb_syslog("starting serial");
serial_fd = start_serial();
/* create file descriptor array */
fds = mkarray();
tcp_fds = mkarray();
j = 0;
for (i = 0; i < length(slaves); i++) {
if (slaves[i].state == "up") {
tcp_fds[j] = slaves[i].fd;
j++;
}
}
fds = array_merge(serial_fd, tcp_fds);
/* loop infinitely */
while (1) {
buffer = "";
rc = select(fds, POLL_TIMEOUT);
if (rc == -1) {
nb_syslog("ERROR: select failed");
} else if (rc == serial_fd) {
/* received something from serial device */
data = read(serial_fd, 4096);
if (data) {
serialbuffer = strcat(serialbuffer, data);
nb_syslog("data on serial port: %s",serialbuffer);
}
} else if (rc != 0 && array_search(tcp_fds, rc) != NULL) {
/* received something from TCP */
data = recv(rc);
len=strlen(data);
if (len > 0) {
/* write to serial device */
write(serial_fd, data, len);
} else if(len == 0) {
//nb_syslog("tcp connection lost, reconnecting");
for (i = 0; i < length(slaves); i++) {
if (rc == slaves[i].fd) {
/* disconnect */
slaves[i].disconnect();
}
}
}
}
/* check serial buffer and send message */
len = strlen(serialbuffer);
msg = serialbuffer;
msglen = len;
serialbuffer = "";
/* send TCP packet to every slave */
if (len > 0) {
for (i = 0; i < length(slaves); i++) {
if (slaves[i].state == "up" ) {
sent = sendbuf(slaves[i].fd, msg, msglen);
if (sent == -1) {
nb_syslog("ERROR: failed to send packet to %s", slaves[i].hostname);
/* disconnect slave */
slaves[i].disconnect();
}
}
}
}
/* check if we have an error on the socket */
for (i = 0; i < length(slaves); i++) {
if (slaves[i].state == "up" ) {
opt = getsockopt(slaves[i].fd, SOL_SOCKET, 4);
if (opt != 0) {
nb_syslog("ERROR: getsockopt(%d) on slave %s failed, reconnecting", opt, slaves[i].hostname);
slaves[i].disconnect();
}
}
}
/* reconnect to disconnected slaves */
for ( i=0; i < length(slaves); i++) {
if (slaves[i].state == "down" ) {
if ( (slaves[i].since + RECOVER_INTERVAL) < slaves[i].jiffy() ) {
slaves[i].connect();
}
}
}
/* re-create file descriptor array */
fds = mkarray();
tcp_fds = mkarray();
j = 0;
for (i = 0; i < length(slaves); i++) {
if (slaves[i].state == "up") {
tcp_fds[j] = slaves[i].fd;
j++;
}
}
fds = array_merge(serial_fd, tcp_fds);
}
exit(0);
