Don't use CLOCK_GETTIME in SDR

6 files changed, 30 insertions, 65 deletions

diff --git a/TODO b/TODO
index 8f49571..ac0a877 100644
--- a/TODO
+++ b/TODO
@@ -18,7 +18,7 @@ https://discourse.myriadrf.org/t/synchronize-two-limesdr/1714
 DPD will be possible too.
 
 
-Move dpd port from uhd section to somewhere else.
+Test sleep_through_frame implementation.
 
 Clean up and separate GPS and refclk checks.
  * *done* handle UHD GPSDO and time
@@ -31,7 +31,7 @@ Add antenna selection to config.
 
 Test RC entries.
 
-Portability: replace clock_gettime with std::chrono
+*done* Portability: replace clock_gettime with std::chrono
 
 *done* Make an abstraction for the DPD feedback server, use it for Soapy and UHD.
 
diff --git a/src/Utils.cpp b/src/Utils.cpp
index f113be3..b4816d3 100644
--- a/src/Utils.cpp
+++ b/src/Utils.cpp
@@ -3,7 +3,7 @@
    Her Majesty the Queen in Right of Canada (Communications Research
    Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -215,16 +215,16 @@ double parseChannel(const std::string& chan)
     return freq;
 }
 
-int transmission_frame_duration_ms(unsigned int dabMode)
+std::chrono::milliseconds transmission_frame_duration(unsigned int dabmode)
 {
-    switch (dabMode) {
-        case 1: return 96;
-        case 2: return 24;
-        case 3: return 24;
-        case 4: return 48;
+    using namespace std::chrono;
+    switch (dabmode) {
+        case 1: return milliseconds(96);
+        case 2: return milliseconds(24);
+        case 3: return milliseconds(24);
+        case 4: return milliseconds(48);
         default:
             throw std::runtime_error("invalid DAB mode");
     }
 }
 
-
diff --git a/src/Utils.h b/src/Utils.h
index 5d5831b..9e88488 100644
--- a/src/Utils.h
+++ b/src/Utils.h
@@ -3,7 +3,7 @@
    Her Majesty the Queen in Right of Canada (Communications Research
    Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -36,6 +36,7 @@
 #include <stdio.h>
 #include <time.h>
 #include <string>
+#include <chrono>
 
 void printUsage(const char* progName);
 
@@ -43,22 +44,6 @@ void printVersion(void);
 
 void printStartupInfo(void);
 
-inline long timespecdiff_us(struct timespec& oldTime, struct timespec& time)
-{
-    long tv_sec;
-    long tv_nsec;
-    if (time.tv_nsec < oldTime.tv_nsec) {
-        tv_sec = time.tv_sec - 1 - oldTime.tv_sec;
-        tv_nsec = 1000000000L + time.tv_nsec - oldTime.tv_nsec;
-    }
-    else {
-        tv_sec = time.tv_sec - oldTime.tv_sec;
-        tv_nsec = time.tv_nsec - oldTime.tv_nsec;
-    }
-
-    return tv_sec * 1000 + tv_nsec / 1000;
-}
-
 // Set SCHED_RR with priority prio (0=lowest)
 int set_realtime_prio(int prio);
 
@@ -70,5 +55,4 @@ double parseChannel(const std::string& chan);
 
 // dabMode is either 1, 2, 3, 4, corresponding to TM I, TM II, TM III and TM IV.
 // throws a runtime_error if dabMode is not one of these values.
-int transmission_frame_duration_ms(unsigned int dabMode);
-
+std::chrono::milliseconds transmission_frame_duration(unsigned int dabmode);
diff --git a/src/output/SDR.cpp b/src/output/SDR.cpp
index e478de5..8906ef6 100644
--- a/src/output/SDR.cpp
+++ b/src/output/SDR.cpp
@@ -59,15 +59,11 @@ static constexpr double TIMESTAMP_MARGIN_FUTURE = 0.5;
 SDR::SDR(SDRDeviceConfig& config, std::shared_ptr<SDRDevice> device) :
     ModOutput(), ModMetadata(), RemoteControllable("sdr"),
     m_config(config),
-    m_running(false),
     m_device(device)
 {
     // muting is remote-controllable
     m_config.muting = false;
 
-    time_last_frame.tv_sec = 0;
-    time_last_frame.tv_nsec = 0;
-
     m_device_thread = std::thread(&SDR::process_thread_entry, this);
 
     m_dpd_feedback_server = make_shared<DPDFeedbackServer>(
@@ -78,15 +74,10 @@ SDR::SDR(SDRDeviceConfig& config, std::shared_ptr<SDRDevice> device) :
 
 SDR::~SDR()
 {
-    stop();
-}
-
-void SDR::stop()
-{
     m_running.store(false);
 
     FrameData end_marker;
-    end_marker.buf.resize(0);
+    end_marker.buf.clear();
     m_queue.push(end_marker);
 
     if (m_device_thread.joinable()) {
@@ -218,33 +209,23 @@ const char* SDR::name()
 
 void SDR::sleep_through_frame()
 {
-    struct timespec now;
-    if (clock_gettime(CLOCK_MONOTONIC, &now) != 0) {
-        stringstream ss;
-        ss << "clock_gettime failure: " << strerror(errno);
-        throw runtime_error(ss.str());
-    }
+    using namespace std::chrono;
 
-    if (time_last_frame.tv_sec == 0) {
-        if (clock_gettime(CLOCK_MONOTONIC, &time_last_frame) != 0) {
-            stringstream ss;
-            ss << "clock_gettime failure: " << strerror(errno);
-            throw runtime_error(ss.str());
-        }
+    const auto now = steady_clock::now();
+
+    if (not t_last_frame_initialised) {
+        t_last_frame = now;
+        t_last_frame_initialised = true;
     }
 
-    long delta_us = timespecdiff_us(time_last_frame, now);
-    long wait_time_us = transmission_frame_duration_ms(m_config.dabMode);
+    const auto delta = now - t_last_frame;
+    const auto wait_time = transmission_frame_duration(m_config.dabMode);
 
-    if (wait_time_us - delta_us > 0) {
-        usleep(wait_time_us - delta_us);
+    if (wait_time > delta) {
+        this_thread::sleep_for(wait_time - delta);
     }
 
-    time_last_frame.tv_nsec += wait_time_us * 1000;
-    while (time_last_frame.tv_nsec >= 1000000000L) {
-        time_last_frame.tv_nsec -= 1000000000L;
-        time_last_frame.tv_sec++;
-    }
+    t_last_frame += wait_time;
 }
 
 void SDR::handle_frame(struct FrameData& frame)
diff --git a/src/output/SDR.h b/src/output/SDR.h
index 4c7de5a..a55f7c0 100644
--- a/src/output/SDR.h
+++ b/src/output/SDR.h
@@ -34,6 +34,7 @@ DESCRIPTION:
 #   include <config.h>
 #endif
 
+#include <chrono>
 #include "ModPlugin.h"
 #include "EtiReader.h"
 #include "output/SDRDevice.h"
@@ -66,14 +67,13 @@ class SDR : public ModOutput, public ModMetadata, public RemoteControllable {
                 const std::string& parameter) const override;
 
     private:
-        void stop(void);
         void process_thread_entry(void);
         void handle_frame(struct FrameData &frame);
         void sleep_through_frame(void);
 
         SDRDeviceConfig& m_config;
 
-        std::atomic<bool> m_running;
+        std::atomic<bool> m_running = ATOMIC_VAR_INIT(false);
         std::thread m_device_thread;
         std::vector<uint8_t> m_frame;
         ThreadsafeQueue<FrameData> m_queue;
@@ -87,8 +87,8 @@ class SDR : public ModOutput, public ModMetadata, public RemoteControllable {
         uint32_t last_tx_second = 0;
         uint32_t last_tx_pps = 0;
 
-        struct timespec time_last_frame;
-
+        bool     t_last_frame_initialised = false;
+        std::chrono::steady_clock::time_point t_last_frame;
 };
 
 }
diff --git a/src/output/USRPTime.cpp b/src/output/USRPTime.cpp
index dcedeab..9ed398e 100644
--- a/src/output/USRPTime.cpp
+++ b/src/output/USRPTime.cpp
@@ -2,7 +2,7 @@
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
    Queen in Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org