initial work on implementing packet radio interface.

can open and read from TTY.
doesn't do anything with the data yet.
doesn't write proper packets to the interface yet.
doesn't use bitrate config option yet.

overlay_interface.c

@@ -400,15 +400,19 @@ overlay_interface_init(const char *name, struct in_addr src_addr, struct in_addr
 
   interface->prefer_unicast = ifconfig->prefer_unicast;
   
-  if (ifconfig->dummy[0]) {
+  if (ifconfig->dummy[0]||ifconfig->type==OVERLAY_INTERFACE_PACKETRADIO) {
     interface->fileP = 1;
     char dummyfile[1024];
+    if (ifconfig->type==OVERLAY_INTERFACE_PACKETRADIO)
+      snprintf(dummyfile, 1024, "%s",ifconfig->dummy);
+    else {
       strbuf d = strbuf_local(dummyfile, sizeof dummyfile);
       strbuf_path_join(d, serval_instancepath(), config.server.dummy_interface_dir, ifconfig->dummy, NULL);
       if (strbuf_overrun(d))
-      return WHYF("dummy interface file name overrun: %s", alloca_str_toprint(strbuf_str(d)));
+	return WHYF("dummy or packet radio interface file name overrun: %s", alloca_str_toprint(strbuf_str(d)));
+    }
     if ((interface->alarm.poll.fd = open(dummyfile,O_APPEND|O_RDWR)) < 1) {
-      return WHYF("could not open dummy interface file %s for append", dummyfile);
+      return WHYF("could not open dummy or packet radio interface file %s for append", dummyfile);
     }
 
     bzero(&interface->address, sizeof(interface->address));
@@ -425,22 +429,37 @@ overlay_interface_init(const char *name, struct in_addr src_addr, struct in_addr
     interface->drop_broadcasts = ifconfig->dummy_filter_broadcasts;
     interface->drop_unicasts = ifconfig->dummy_filter_unicasts;
     
+    if (interface->type!=OVERLAY_INTERFACE_PACKETRADIO) {
       /* Seek to end of file as initial reading point */
       interface->recv_offset = lseek(interface->alarm.poll.fd,0,SEEK_END);
       /* XXX later add pretend location information so that we can decide which "packets" to receive
 	 based on closeness */    
+    } else {
+      // Setup packet radio device
+      // XXX This needs to be parameterised at some point
+      // Make sure it is not in command mode
+      write(interface->alarm.poll.fd,"ATO\r",4);
+    }
 
     // schedule an alarm for this interface
+    if (interface->type!=OVERLAY_INTERFACE_PACKETRADIO) {
       interface->alarm.function=overlay_dummy_poll;
+      dummy_poll_stats.name="overlay_dummy_poll";
+    } else {
+      interface->alarm.function=overlay_packetradio_poll;
+      dummy_poll_stats.name="overlay_packetradio_poll";
+    }
     interface->alarm.alarm=gettime_ms()+10;
     interface->alarm.deadline=interface->alarm.alarm;
-    dummy_poll_stats.name="overlay_dummy_poll";
     interface->alarm.stats=&dummy_poll_stats;
     schedule(&interface->alarm);
     
     interface->state=INTERFACE_STATE_UP;
+    if (interface->type!=OVERLAY_INTERFACE_PACKETRADIO)
       INFOF("Dummy interface %s addr %s:%d, is up",interface->name,
 	    inet_ntoa(interface->address.sin_addr), ntohs(interface->address.sin_port));
+    else
+      INFOF("Packet radio interface %s, is up",interface->name);
     
     directory_registration();
     
@@ -545,6 +564,44 @@ struct dummy_packet{
   unsigned char payload[1400];
 };
 
+void overlay_packetradio_poll(struct sched_ent *alarm)
+{
+  overlay_interface *interface = (overlay_interface *)alarm;
+  time_ms_t now = gettime_ms();
+
+  // We will almost certainly support more than one type of packet radio
+  // so lets parameterise this.
+  switch(1) {
+  case 1:
+    // Read data from the serial port
+    break;
+  }
+
+  // tick the interface
+  if (interface->tick_ms>0 && 
+      (interface->last_tick_ms == -1 || now >= interface->last_tick_ms + interface->tick_ms)) {
+    // tick the interface
+    overlay_route_queue_advertisements(interface);
+    interface->last_tick_ms=now;
+  }
+  
+  unsigned char buffer[8192];
+  ssize_t nread = read(alarm->poll.fd, buffer,8192);
+  if (nread == -1){
+    WHY_perror("read");
+    return;
+  }
+  if (nread>0) {
+    buffer[8191]=0;
+    if (nread<8192) buffer[nread]=0;
+    DEBUGF("Read '%s'",buffer);
+  }
+
+  schedule(alarm);
+
+  return ;
+}
+
 void overlay_dummy_poll(struct sched_ent *alarm)
 {
   overlay_interface *interface = (overlay_interface *)alarm;
@@ -707,7 +764,7 @@ overlay_interface_register(char *name,
   int i;
   for (i = 0; i < config.interfaces.ac; ++i, ifconfig = NULL) {
     ifconfig = &config.interfaces.av[i].value;
-    if (!ifconfig->dummy[0]) {
+    if ((!ifconfig->dummy[0])&&ifconfig->type!=OVERLAY_INTERFACE_PACKETRADIO) {
       int j;
       for (j = 0; j < ifconfig->match.patc; ++j){
 	if (fnmatch(ifconfig->match.patv[j], name, 0) == 0)
@@ -791,17 +848,18 @@ void overlay_interface_discover(struct sched_ent *alarm)
   const struct config_network_interface *ifconfig = NULL;
   for (i = 0; i < config.interfaces.ac; ++i, ifconfig = NULL) {
     ifconfig = &config.interfaces.av[i].value;
-    if (!ifconfig->dummy[0]) {
+    if (ifconfig->type!=OVERLAY_INTERFACE_PACKETRADIO&&(!ifconfig->dummy[0])) {
       detect_real_interfaces = 1;
       continue;
     }
-    for (i = 0; i < overlay_interface_count; i++)
+    int j;
-      if (strcasecmp(overlay_interfaces[i].name, ifconfig->dummy) == 0) {
+    for (j = 0; j < overlay_interface_count; j++)
-	if (overlay_interfaces[i].state==INTERFACE_STATE_DETECTING)
+      if (strcasecmp(overlay_interfaces[j].name, ifconfig->dummy) == 0) {
-	  overlay_interfaces[i].state=INTERFACE_STATE_UP;
+	if (overlay_interfaces[j].state==INTERFACE_STATE_DETECTING)
+	  overlay_interfaces[j].state=INTERFACE_STATE_UP;
 	break;
       }
-    if (i >= overlay_interface_count) {
+    if (j >= overlay_interface_count) {
       // New dummy interface, so register it.
       struct in_addr dummyaddr = hton_in_addr(INADDR_NONE);
       overlay_interface_init(ifconfig->dummy, dummyaddr, dummyaddr, dummyaddr, ifconfig);

serval.h

@@ -743,6 +743,7 @@ int _unwatch(struct __sourceloc whence, struct sched_ent *alarm);
 int fd_poll();
 
 void overlay_interface_discover(struct sched_ent *alarm);
+void overlay_packetradio_poll(struct sched_ent *alarm);
 void overlay_dummy_poll(struct sched_ent *alarm);
 void overlay_route_tick(struct sched_ent *alarm);
 void server_config_reload(struct sched_ent *alarm);