Do not crash if ntp has been synced once and it fails next time (can happen when laptop lid is closed)

1 files changed, 18 insertions, 4 deletions

diff --git a/src/Database.cpp b/src/Database.cpp
index 27caba0..155e8f5 100644
--- a/src/Database.cpp
+++ b/src/Database.cpp
@@ -144,8 +144,9 @@ namespace odhtdb
                 delete ntpThread;
             
             const int ntpFetchTimestampRetries = 5;
+            const int ntpFetchFailRetryCooldownSec = 60;
 
-            ntpThread = new thread([]()
+            ntpThread = new thread([ntpFetchFailRetryCooldownSec]()
             {
                 ntp::NtpClient ntpClient("pool.ntp.org", 10);
                 while(databaseCount > 0)
@@ -166,17 +167,30 @@ namespace odhtdb
                         catch(ntp::NtpClientException &e)
                         {
                             Log::warn("Failed to sync clock with ntp server, reason: %s. Try #%d", e.what(), fetchRetryCounter);
-                            this_thread::sleep_for(500ms);
+                            if(timestampSynced)
+                                this_thread::sleep_for(3s);
                         }
                         ++fetchRetryCounter;
                     }
                     
                     if(fetchRetryCounter == ntpFetchTimestampRetries)
-                        throw ntp::NtpClientException("Failed to retrieve ntp timestamp after several retries");
+                    {
+                        if(!timestampSynced)
+                        {
+                            string errMsg = "Failed to retrieve ntp timestamp after ";
+                            errMsg += to_string(ntpFetchTimestampRetries);
+                            errMsg += " retries, giving up";
+                            throw ntp::NtpClientException(errMsg);
+                        }
+                        else
+                        {
+                            Log::warn("Failed to retrieve ntp timestamp after %d retries, retrying in %d seconds", ntpFetchTimestampRetries, ntpFetchFailRetryCooldownSec);
+                            this_thread::sleep_for(chrono::seconds(ntpFetchFailRetryCooldownSec));
+                        }
+                    }
                     
                     this_thread::sleep_for(60s);
                 }
-                timestampSynced = false;
             });
             ntpThread->detach();
         }