From db9a7df50a39474019568187e4fb5c4321bebc3f Mon Sep 17 00:00:00 2001 From: "Matthias P. Braendli" Date: Mon, 7 Jan 2019 14:41:00 +0100 Subject: ClockTAI: refactor downloading slightly --- src/ClockTAI.cpp | 137 ++++++++++++++++++++++++++++++------------------------- 1 file changed, 74 insertions(+), 63 deletions(-) (limited to 'src') diff --git a/src/ClockTAI.cpp b/src/ClockTAI.cpp index 787eb4d..00a9aeb 100644 --- a/src/ClockTAI.cpp +++ b/src/ClockTAI.cpp @@ -78,54 +78,6 @@ static array default_tai_urls = { // /var/tmp "must not be deleted when the system is booted." static const char *tai_cache_location = "/var/tmp/odr-dabmux-leap-seconds.cache"; -struct bulletin_state { - bool valid = false; - int64_t expiry = 0; - - bool usable() const { return valid and expiry > 0; } -}; - -static bulletin_state parse_bulletin(const string& bulletin) -{ - // The bulletin contains one line that specifies an expiration date - // in NTP time. If that point in time is in the future, we consider - // the bulletin valid. - // - // The entry looks like this: - //#@ 3707596800 - - bulletin_state ret; - - std::regex regex_expiration(R"(#@\s+([0-9]+))"); - - time_t now = time(nullptr); - - stringstream ss(bulletin); - - for (string line; getline(ss, line); ) { - std::smatch bulletin_entry; - - bool is_match = std::regex_search(line, bulletin_entry, regex_expiration); - if (is_match) { - if (bulletin_entry.size() != 2) { - throw runtime_error( - "Incorrect number of matched TAI IETF bulletin expiration"); - } - const string expiry_data_str(bulletin_entry[1]); - const int64_t expiry_unix = - std::atoll(expiry_data_str.c_str()) - ntp_unix_offset; - -#ifdef TEST - etiLog.level(info) << "Bulletin expires in " << expiry_unix - now; -#endif - ret.expiry = expiry_unix - now; - ret.valid = true; - break; - } - } - return ret; -} - // read TAI offset from a valid bulletin in IETF format static int parse_ietf_bulletin(const std::string& bulletin) { @@ -193,6 +145,62 @@ static int parse_ietf_bulletin(const std::string& bulletin) } +struct bulletin_state { + bool valid = false; + int64_t expiry = 0; + int offset = 0; + + bool usable() const { return valid and expiry > 0; } +}; + +static bulletin_state parse_bulletin(const string& bulletin) +{ + // The bulletin contains one line that specifies an expiration date + // in NTP time. If that point in time is in the future, we consider + // the bulletin valid. + // + // The entry looks like this: + //#@ 3707596800 + + bulletin_state ret; + + std::regex regex_expiration(R"(#@\s+([0-9]+))"); + + time_t now = time(nullptr); + + stringstream ss(bulletin); + + for (string line; getline(ss, line); ) { + std::smatch bulletin_entry; + + bool is_match = std::regex_search(line, bulletin_entry, regex_expiration); + if (is_match) { + if (bulletin_entry.size() != 2) { + throw runtime_error( + "Incorrect number of matched TAI IETF bulletin expiration"); + } + const string expiry_data_str(bulletin_entry[1]); + const int64_t expiry_unix = + std::atoll(expiry_data_str.c_str()) - ntp_unix_offset; + +#ifdef TEST + etiLog.level(info) << "Bulletin expires in " << expiry_unix - now; +#endif + ret.expiry = expiry_unix - now; + try { + ret.offset = parse_ietf_bulletin(bulletin); + ret.valid = true; + } + catch (const runtime_error& e) { + etiLog.level(warn) << "Bulletin expiry ok but parse error: " << e.what(); + } + break; + } + } + return ret; +} + + // callback that receives data from cURL static size_t fill_bulletin(char *ptr, size_t size, size_t nmemb, void *ctx) { @@ -279,22 +287,25 @@ int ClockTAI::get_valid_offset() std::unique_lock lock(m_data_mutex); - if (parse_bulletin(m_bulletin).usable()) { + const auto state = parse_bulletin(m_bulletin); + if (state.usable()) { #if TEST etiLog.level(info) << "Bulletin already valid"; #endif - offset = parse_ietf_bulletin(m_bulletin); + offset = state.offset; offset_valid = true; } else { const auto cache_bulletin = load_bulletin_from_file(tai_cache_location); - if (parse_bulletin(cache_bulletin).usable()) { + const auto cache_state = parse_bulletin(cache_bulletin); + + if (cache_state.usable()) { m_bulletin = cache_bulletin; + offset = cache_state.offset; + offset_valid = true; #if TEST - etiLog.level(info) << "Bulletin from cache valid"; + etiLog.level(info) << "Bulletin from cache valid with offset=" << offset; #endif - offset = parse_ietf_bulletin(m_bulletin); - offset_valid = true; } else { for (const auto url : m_bulletin_urls) { @@ -303,9 +314,10 @@ int ClockTAI::get_valid_offset() etiLog.level(info) << "Load bulletin from " << url; #endif const auto new_bulletin = download_tai_utc_bulletin(url.c_str()); - if (parse_bulletin(new_bulletin).usable()) { + const auto new_state = parse_bulletin(new_bulletin); + if (new_state.usable()) { m_bulletin = new_bulletin; - offset = parse_ietf_bulletin(m_bulletin); + offset = new_state.offset; offset_valid = true; etiLog.level(debug) << "Loaded valid TAI Bulletin from " << @@ -343,8 +355,6 @@ int ClockTAI::get_valid_offset() } else { // Try again later - m_bulletin_download_time += chrono::hours(download_retry_interval_hours); - throw download_failed(); } } @@ -365,7 +375,7 @@ int ClockTAI::get_offset() m_offset_valid = true; // Simulate requiring a new download - m_bulletin_download_time = system_clock::now() - hours(24 * 40); + m_bulletin_download_time = time_now - hours(24 * 40); #else // First time we run we must block until we know // the offset @@ -378,7 +388,7 @@ int ClockTAI::get_offset() } lock.lock(); m_offset_valid = true; - m_bulletin_download_time = system_clock::now(); + m_bulletin_download_time = time_now; #endif etiLog.level(info) << "Initialised TAI-UTC offset to " << m_offset << "s."; @@ -396,7 +406,7 @@ int ClockTAI::get_offset() try { m_offset = m_offset_future.get(); m_offset_valid = true; - m_bulletin_download_time = system_clock::now(); + m_bulletin_download_time = time_now; etiLog.level(info) << "Updated TAI-UTC offset to " << m_offset << "s."; @@ -405,6 +415,8 @@ int ClockTAI::get_offset() etiLog.level(warn) << "TAI-UTC download failed, will retry in " << download_retry_interval_hours << " hour(s)"; + + m_bulletin_download_time += hours(download_retry_interval_hours); } #ifdef TEST wait_longer = false; @@ -424,8 +436,7 @@ int ClockTAI::get_offset() #ifdef TEST etiLog.level(debug) << " Launch async"; #endif - m_offset_future = async(launch::async, - &ClockTAI::get_valid_offset, this); + m_offset_future = async(launch::async, &ClockTAI::get_valid_offset, this); } } -- cgit v1.2.3