3 files changed, 28 insertions, 6 deletions
diff --git a/lib/usrp/mboard/usrp2.cpp b/lib/usrp/mboard/usrp2.cpp
index d51b37602..9282a541a 100644
--- a/lib/usrp/mboard/usrp2.cpp
+++ b/lib/usrp/mboard/usrp2.cpp
@@ -21,6 +21,7 @@
 #include <uhd/device.hpp>
 #include <boost/thread.hpp>
 #include <boost/lexical_cast.hpp>
+#include <boost/thread.hpp>
 #include <netinet/in.h>
 
 using namespace uhd::usrp::mboard;
@@ -36,11 +37,31 @@ std::vector<uhd::device_addr_t> usrp2::discover(const device_addr_t &hint){
     uhd::transport::udp udp_transport(hint.udp_args.addr, ctrl_port, true);
 
     //send a hello control packet
-    usrp2_ctrl_data_t data;
-    data.id = htonl(USRP2_CTRL_ID_HELLO);
-    udp_transport.send(&data, sizeof(data));
+    usrp2_ctrl_data_t ctrl_data_out;
+    ctrl_data_out.id = htonl(USRP2_CTRL_ID_HELLO);
+    udp_transport.send(boost::asio::buffer(&ctrl_data_out, sizeof(ctrl_data_out)));
 
-    //TODO start a thread to listen and sleep for timeout
+    //loop and recieve until the time is up
+    size_t num_timeouts = 0;
+    while(true){
+        boost::asio::const_buffer buff = udp_transport.recv();
+        //std::cout << boost::asio::buffer_size(buff) << "\n";
+        if (boost::asio::buffer_size(buff) < sizeof(usrp2_ctrl_data_t)){
+            //sleep a little so we dont burn cpu
+            if (num_timeouts++ > 50) break;
+            boost::this_thread::sleep(boost::posix_time::milliseconds(1));
+        }else{
+            //handle the received data
+            const usrp2_ctrl_data_t *ctrl_data_in = boost::asio::buffer_cast<const usrp2_ctrl_data_t *>(buff);
+            switch(ntohl(ctrl_data_in->id)){
+            case USRP2_CTRL_ID_HELLO:
+                //make a boost asio ipv4 with the raw addr in host byte order
+                boost::asio::ip::address_v4 ip_addr(ntohl(ctrl_data_in->data.discovery_addrs.ip_addr));
+                std::cout << "hello " << ip_addr.to_string() << "\n";
+                break;
+            }
+        }
+    }
 
     return usrp2_addrs;
 }
diff --git a/lib/usrp/mboard/usrp2_fw_common.h b/lib/usrp/mboard/usrp2_fw_common.h
index 28d58cf7c..217d8cf1c 100644
--- a/lib/usrp/mboard/usrp2_fw_common.h
+++ b/lib/usrp/mboard/usrp2_fw_common.h
@@ -33,6 +33,7 @@ extern "C" {
 #define USRP2_UDP_DATA_PORT 49153
 
 typedef enum{
+    USRP2_CTRL_ID_NONE,
     USRP2_CTRL_ID_HELLO
 } usrp2_ctrl_id_t;
 
diff --git a/lib/usrp/usrp.cpp b/lib/usrp/usrp.cpp
index d188f51a7..c49a63d49 100644
--- a/lib/usrp/usrp.cpp
+++ b/lib/usrp/usrp.cpp
@@ -32,7 +32,7 @@ static void send_raw_default(const std::vector<boost::asio::const_buffer> &){
     throw std::runtime_error("No callback registered for send raw");
 }
 
-static const boost::asio::const_buffer recv_raw_default(void){
+static boost::asio::const_buffer recv_raw_default(void){
     throw std::runtime_error("No callback registered for recv raw");
 }
 
@@ -87,6 +87,6 @@ void usrp::send_raw(const std::vector<boost::asio::const_buffer> &buffs){
     return _send_raw_cb(buffs);
 }
 
-const boost::asio::const_buffer usrp::recv_raw(void){
+boost::asio::const_buffer usrp::recv_raw(void){
     return _recv_raw_cb();
 }