Fix important EDI Timestamp issues

First, use more servers, not only those from USNO that currenty show problems.
Add a server from IETF and the github repository from the tz project that mirrors
that file.

Second, fix issues about parsing the bulletin and error handling.

Third, run the bulletin update asynchronously once the mux runs, to avoid blocking it.

1 files changed, 20 insertions, 16 deletions

diff --git a/src/ClockTAI.h b/src/ClockTAI.h
index 499fa56..6ab9ab6 100644
--- a/src/ClockTAI.h
+++ b/src/ClockTAI.h
@@ -3,7 +3,7 @@
    2011, 2012 Her Majesty the Queen in Right of Canada (Communications
    Research Center Canada)
 
-   Copyright (C) 2016
+   Copyright (C) 2017
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://www.opendigitalradio.org
@@ -26,18 +26,19 @@
 */
 
 /* The EDI output needs TAI clock, according to ETSI TS 102 693 Annex F
- * "EDI Timestamps". This module sets the local CLOCK_TAI clock by
+ * "EDI Timestamps". This module can set the local CLOCK_TAI clock by
  * setting the TAI-UTC offset using adjtimex.
  *
- * This functionality requires Linux 3.10 (30 Jun 2013) or newer */
+ * This functionality requires Linux 3.10 (30 Jun 2013) or newer.
+ */
 
-#ifndef __CLOCK_TAI_H_
-#define __CLOCK_TAI_H_
+#pragma once
 
 #include <stdint.h>
 #include <stdlib.h>
 #include <sstream>
 #include <chrono>
+#include <future>
 
 // EDI needs to know UTC-TAI, but doesn't need the CLOCK_TAI to be set.
 // We can keep this code, maybe for future use
@@ -46,8 +47,6 @@
 /* Loads, parses and represents TAI-UTC offset information from the USNO bulletin */
 class ClockTAI {
     public:
-        ClockTAI();
-
         // Fetch the bulletin from the USNO website and return the current
         // TAI-UTC offset.
         // Throws runtime_error on failure.
@@ -60,19 +59,26 @@ class ClockTAI {
 #endif
 
     private:
-        // leap seconds insertion bulletin is available at
-        const char* tai_data_url1 = "http://maia.usno.navy.mil/ser7/tai-utc.dat";
-        const char* tai_data_url2 = "http://toshi.nofs.navy.mil/ser7/tai-utc.dat";
+        int download_offset_task(void);
+
+        // Download of new bulletin is done asynchronously
+        std::future<int> m_offset_future;
 
+        // The currently used TAI-UTC offset
         int m_offset;
+        int m_offset_valid = false;
+
         std::stringstream m_bulletin;
         std::chrono::system_clock::time_point m_bulletin_download_time;
 
-        // Load bulletin into m_bulletin, return 0 on success
-        int download_tai_utc_bulletin(const char* url);
+        // Load bulletin into m_bulletin
+        void download_tai_utc_bulletin(const char* url);
 
-        // read TAI offset from m_bulletin
-        int parse_tai_offset(void);
+        // read TAI offset from m_bulletin in IETF format
+        int parse_ietf_bulletin(void);
+
+        // read TAI offset from m_bulletin in USNO format
+        int parse_usno_bulletin(void);
 
         // callback that receives data from cURL
         size_t fill_bulletin(char *ptr, size_t size, size_t nmemb);
@@ -82,5 +88,3 @@ class ClockTAI {
                 char *ptr, size_t size, size_t nmemb, void *ctx);
 };
 
-#endif // __CLOCK_TAI_H_
-