Add real timestamp to log output when mock time is enabled (#2604)

* Implement IsMockTime to test for mock time

* Add real timestamp to log output when mock time is enabled

This makes debugging on Travis easier as it gives a hint about timing
behavior.

src/util.cpp

@@ -316,8 +316,12 @@ static std::string LogTimestampStr(const std::string &str, std::atomic_bool *fSt
         return str;
 
     if (*fStartedNewLine) {
+        if (IsMockTime()) {
+            int64_t nRealTimeMicros = GetTimeMicros();
+            strStamped = DateTimeStrFormat("(real %Y-%m-%d %H:%M:%S) ", nRealTimeMicros/1000000);
+        }
         int64_t nTimeMicros = GetLogTimeMicros();
-        strStamped = DateTimeStrFormat("%Y-%m-%d %H:%M:%S", nTimeMicros/1000000);
+        strStamped += DateTimeStrFormat("%Y-%m-%d %H:%M:%S", nTimeMicros/1000000);
         if (fLogTimeMicros)
             strStamped += strprintf(".%06d", nTimeMicros%1000000);
         strStamped += ' ' + str;

src/utiltime.cpp

@@ -29,6 +29,11 @@ void SetMockTime(int64_t nMockTimeIn)
     nMockTime = nMockTimeIn;
 }
 
+bool IsMockTime()
+{
+    return nMockTime != 0;
+}
+
 int64_t GetTimeMillis()
 {
     int64_t now = (boost::posix_time::microsec_clock::universal_time() -

src/utiltime.h

@@ -25,6 +25,7 @@ int64_t GetTimeMicros();
 int64_t GetSystemTimeInSeconds(); // Like GetTime(), but not mockable
 int64_t GetLogTimeMicros();
 void SetMockTime(int64_t nMockTimeIn);
+bool IsMockTime();
 void MilliSleep(int64_t n);
 
 std::string DateTimeStrFormat(const char* pszFormat, int64_t nTime);