utils: query_gpsdo_sensors: Fix ref_lock wait loop

The old loop didn't have any output, and had an inaccurate timeout. We
now use a timer for a 30 second timeout, and print a . every time we
poll the sensor.

1 files changed, 4 insertions, 1 deletions

diff --git a/host/utils/query_gpsdo_sensors.cpp b/host/utils/query_gpsdo_sensors.cpp
index 4a8aa24d2..ecc0048a7 100644
--- a/host/utils/query_gpsdo_sensors.cpp
+++ b/host/utils/query_gpsdo_sensors.cpp
@@ -162,10 +162,13 @@ int UHD_SAFE_MAIN(int argc, char* argv[])
     // Check for ref lock
     if (std::find(sensor_names.begin(), sensor_names.end(), "ref_locked")
         != sensor_names.end()) {
+        std::cout << "Waiting for ref_locked..." << std::flush;
         uhd::sensor_value_t ref_locked = usrp->get_mboard_sensor("ref_locked", 0);
-        for (size_t i = 0; not ref_locked.to_bool() and i < 300; i++) {
+        auto end = std::chrono::steady_clock::now() + std::chrono::seconds(30);
+        while (!ref_locked.to_bool() && std::chrono::steady_clock::now() < end) {
             std::this_thread::sleep_for(std::chrono::milliseconds(100));
             ref_locked = usrp->get_mboard_sensor("ref_locked", 0);
+            std::cout << "." << std::flush;
         }
         if (not ref_locked.to_bool()) {
             std::cout << boost::format("USRP NOT Locked to Reference.\n");