CTest: add safe conversion from cmDuration to integer types

A problem area by recent refactoring of time to std::chrono has been the
unsafe conversion from duration<double> to std::chrono::seconds, which
is of an unspecified integer type.

This commit adds a template function that for a given type provides a
safe conversion, effectively clamping a duration<double> into what fits
safely in that type. A specialisation for int and unsigned int are
provided.

It changes the protential problem areas to use this safe function.

3 files changed, 22 insertions, 30 deletions

diff --git a/Source/CTest/cmCTestMemCheckHandler.cxx b/Source/CTest/cmCTestMemCheckHandler.cxx
index 6b6c337..c3fbc0d 100644
--- a/Source/CTest/cmCTestMemCheckHandler.cxx
+++ b/Source/CTest/cmCTestMemCheckHandler.cxx
@@ -3,6 +3,7 @@
 #include "cmCTestMemCheckHandler.h"
 
 #include "cmCTest.h"
+#include "cmDuration.h"
 #include "cmSystemTools.h"
 #include "cmXMLParser.h"
 #include "cmXMLWriter.h"
@@ -920,12 +921,11 @@ bool cmCTestMemCheckHandler::ProcessMemCheckValgrindOutput(
       break; // stop the copy of output if we are full
     }
   }
-  cmCTestOptionalLog(this->CTest, DEBUG, "End test (elapsed: "
-                       << std::chrono::duration_cast<std::chrono::seconds>(
-                            std::chrono::steady_clock::now() - sttime)
-                            .count()
-                       << "s)" << std::endl,
-                     this->Quiet);
+  cmCTestOptionalLog(
+    this->CTest, DEBUG, "End test (elapsed: "
+      << cmDurationTo<unsigned int>(std::chrono::steady_clock::now() - sttime)
+      << "s)" << std::endl,
+    this->Quiet);
   log = ostr.str();
   this->DefectCount += defects;
   return defects == 0;
@@ -966,12 +966,11 @@ bool cmCTestMemCheckHandler::ProcessMemCheckBoundsCheckerOutput(
     results[err]++;
     defects++;
   }
-  cmCTestOptionalLog(this->CTest, DEBUG, "End test (elapsed: "
-                       << std::chrono::duration_cast<std::chrono::seconds>(
-                            std::chrono::steady_clock::now() - sttime)
-                            .count()
-                       << "s)" << std::endl,
-                     this->Quiet);
+  cmCTestOptionalLog(
+    this->CTest, DEBUG, "End test (elapsed: "
+      << cmDurationTo<unsigned int>(std::chrono::steady_clock::now() - sttime)
+      << "s)" << std::endl,
+    this->Quiet);
   if (defects) {
     // only put the output of Bounds Checker if there were
     // errors or leaks detected
diff --git a/Source/CTest/cmCTestRunTest.cxx b/Source/CTest/cmCTestRunTest.cxx
index a5ec93d..8d602fa 100644
--- a/Source/CTest/cmCTestRunTest.cxx
+++ b/Source/CTest/cmCTestRunTest.cxx
@@ -621,17 +621,11 @@ bool cmCTestRunTest::ForkProcess(cmDuration testTimeOut, bool explicitTimeout,
   if (testTimeOut == cmDuration::zero() && explicitTimeout) {
     timeout = cmDuration::zero();
   }
-  cmCTestOptionalLog(
-    this->CTest, HANDLER_VERBOSE_OUTPUT, this->Index
-      << ": "
-      << "Test timeout computed to be: "
-      << (timeout == cmCTest::MaxDuration()
-            ? std::string("infinite")
-            : std::to_string(
-                std::chrono::duration_cast<std::chrono::seconds>(timeout)
-                  .count()))
-      << "\n",
-    this->TestHandler->GetQuiet());
+  cmCTestOptionalLog(this->CTest, HANDLER_VERBOSE_OUTPUT, this->Index
+                       << ": "
+                       << "Test timeout computed to be: "
+                       << cmDurationTo<unsigned int>(timeout) << "\n",
+                     this->TestHandler->GetQuiet());
 
   this->TestProcess->SetTimeout(timeout);
 
diff --git a/Source/CTest/cmCTestScriptHandler.cxx b/Source/CTest/cmCTestScriptHandler.cxx
index d5faeb5..15a81f2 100644
--- a/Source/CTest/cmCTestScriptHandler.cxx
+++ b/Source/CTest/cmCTestScriptHandler.cxx
@@ -159,9 +159,9 @@ void cmCTestScriptHandler::UpdateElapsedTime()
 {
   if (this->Makefile) {
     // set the current elapsed time
-    auto itime = std::chrono::duration_cast<std::chrono::seconds>(
-      std::chrono::steady_clock::now() - this->ScriptStartTime);
-    auto timeString = std::to_string(itime.count());
+    auto itime = cmDurationTo<unsigned int>(std::chrono::steady_clock::now() -
+                                            this->ScriptStartTime);
+    auto timeString = std::to_string(itime);
     this->Makefile->AddDefinition("CTEST_ELAPSED_TIME", timeString.c_str());
   }
 }
@@ -569,10 +569,9 @@ int cmCTestScriptHandler::RunCurrentScript()
       auto interval = std::chrono::steady_clock::now() - startOfInterval;
       auto minimumInterval = cmDuration(this->MinimumInterval);
       if (interval < minimumInterval) {
-        auto sleepTime = std::chrono::duration_cast<std::chrono::seconds>(
-                           minimumInterval - interval)
-                           .count();
-        this->SleepInSeconds(static_cast<unsigned int>(sleepTime));
+        auto sleepTime =
+          cmDurationTo<unsigned int>(minimumInterval - interval);
+        this->SleepInSeconds(sleepTime);
       }
       if (this->EmptyBinDirOnce) {
         this->EmptyBinDir = false;