CTest: use std::chrono::steady_clock for time keeping

It was reported in issue #17345 that CTest does not use monotonic time
to report test duration. Monotonic clocks are not affected by large NTP
adjustments or things like daylight savings time.

As CMake 3.10 requires C++11, which introduced std::chrono, this commit
moves the time keeping in CTest from cmSystemTools::GetTime() to
std::chrono::steady_clock.

Fixes: #17345

1 files changed, 16 insertions, 6 deletions

diff --git a/Source/CTest/cmCTestMemCheckHandler.cxx b/Source/CTest/cmCTestMemCheckHandler.cxx
index 3efb039..2e7874d 100644
--- a/Source/CTest/cmCTestMemCheckHandler.cxx
+++ b/Source/CTest/cmCTestMemCheckHandler.cxx
@@ -10,9 +10,11 @@
 #include "cmsys/FStream.hxx"
 #include "cmsys/Glob.hxx"
 #include "cmsys/RegularExpression.hxx"
+#include <chrono>
 #include <iostream>
 #include <sstream>
 #include <string.h>
+#include <type_traits>
 
 struct CatToErrorType
 {
@@ -408,8 +410,10 @@ void cmCTestMemCheckHandler::GenerateDartOutput(cmXMLWriter& xml)
 
   xml.Element("EndDateTime", this->EndTest);
   xml.Element("EndTestTime", this->EndTestTime);
-  xml.Element("ElapsedMinutes",
-              static_cast<int>(this->ElapsedTestingTime / 6) / 10.0);
+  xml.Element(
+    "ElapsedMinutes",
+    std::chrono::duration_cast<std::chrono::minutes>(this->ElapsedTestingTime)
+      .count());
 
   xml.EndElement(); // DynamicAnalysis
   this->CTest->EndXML(xml);
@@ -844,7 +848,7 @@ bool cmCTestMemCheckHandler::ProcessMemCheckValgrindOutput(
   cmsys::RegularExpression vgABR("== .*pthread_mutex_unlock: mutex is "
                                  "locked by a different thread");
   std::vector<std::string::size_type> nonValGrindOutput;
-  double sttime = cmSystemTools::GetTime();
+  auto sttime = std::chrono::steady_clock::now();
   cmCTestOptionalLog(this->CTest, DEBUG,
                      "Start test: " << lines.size() << std::endl, this->Quiet);
   std::string::size_type totalOutputSize = 0;
@@ -918,7 +922,10 @@ bool cmCTestMemCheckHandler::ProcessMemCheckValgrindOutput(
     }
   }
   cmCTestOptionalLog(this->CTest, DEBUG, "End test (elapsed: "
-                       << (cmSystemTools::GetTime() - sttime) << std::endl,
+                       << std::chrono::duration_cast<std::chrono::seconds>(
+                            std::chrono::steady_clock::now() - sttime)
+                            .count()
+                       << "s)" << std::endl,
                      this->Quiet);
   log = ostr.str();
   this->DefectCount += defects;
@@ -929,7 +936,7 @@ bool cmCTestMemCheckHandler::ProcessMemCheckBoundsCheckerOutput(
   const std::string& str, std::string& log, std::vector<int>& results)
 {
   log.clear();
-  double sttime = cmSystemTools::GetTime();
+  auto sttime = std::chrono::steady_clock::now();
   std::vector<std::string> lines;
   cmSystemTools::Split(str.c_str(), lines);
   cmCTestOptionalLog(this->CTest, DEBUG,
@@ -961,7 +968,10 @@ bool cmCTestMemCheckHandler::ProcessMemCheckBoundsCheckerOutput(
     defects++;
   }
   cmCTestOptionalLog(this->CTest, DEBUG, "End test (elapsed: "
-                       << (cmSystemTools::GetTime() - sttime) << std::endl,
+                       << std::chrono::duration_cast<std::chrono::seconds>(
+                            std::chrono::steady_clock::now() - sttime)
+                            .count()
+                       << "s)" << std::endl,
                      this->Quiet);
   if (defects) {
     // only put the output of Bounds Checker if there were