Fix localtime/gmtime usage (#1227)

* Prefer the reentrant versions of localtime/gmtime when available

* Simplify pragmas

* Review comment fixes

* Remove comment

2 files changed, 13 insertions, 18 deletions

diff --git a/cpp/src/IceSSL/OpenSSLCertificateI.cpp b/cpp/src/IceSSL/OpenSSLCertificateI.cpp
index db83275bc22..7109710f048 100644
--- a/cpp/src/IceSSL/OpenSSLCertificateI.cpp
+++ b/cpp/src/IceSSL/OpenSSLCertificateI.cpp
@@ -209,24 +209,21 @@ ASMUtcTimeToTime(const ASN1_UTCTIME* s)
     }
 #  undef g2
 
-    //
-    // If timegm was on all systems this code could be
-    // return IceUtil::Time::seconds(timegm(&tm) - offset*60);
-    //
-    // Windows doesn't support the re-entrant _r versions.
-    //
-#if defined(_MSC_VER)
-#   pragma warning(disable:4996) // localtime is depercated
-#endif
     time_t tzone;
     {
         IceUtilInternal::MutexPtrLock<IceUtil::Mutex> sync(mut);
         time_t now = time(0);
-        tzone = mktime(localtime(&now)) - mktime(gmtime(&now));
-    }
+        struct tm localTime;
+        struct tm gmTime;
 #if defined(_MSC_VER)
-#   pragma warning(default:4996) // localtime is depercated
+        localtime_s(&localTime, &now);
+        gmtime_s(&gmTime, &now);
+#else
+        localtime_r(&now, &localTime);
+        gmtime_r(&now, &gmTime);
 #endif
+        tzone = mktime(&localTime) - mktime(&gmTime);
+    }
 
     IceUtil::Time time = IceUtil::Time::seconds(mktime(&tm) - IceUtil::Int64(offset) * 60 + tzone);
 
diff --git a/cpp/src/IceUtil/Time.cpp b/cpp/src/IceUtil/Time.cpp
index bac201a055d..68d775d0a9a 100644
--- a/cpp/src/IceUtil/Time.cpp
+++ b/cpp/src/IceUtil/Time.cpp
@@ -280,17 +280,15 @@ IceUtil::Time::toString(const std::string& format) const
 {
     time_t time = static_cast<long>(_usec / 1000000);
 
-    struct tm* t;
-#ifdef _WIN32
-    t = localtime(&time);
-#else
     struct tm tr;
+#ifdef _MSC_VER
+    localtime_s(&tr, &time);
+#else
     localtime_r(&time, &tr);
-    t = &tr;
 #endif
 
     char buf[32];
-    if(strftime(buf, sizeof(buf), format.c_str(), t) == 0)
+    if(strftime(buf, sizeof(buf), format.c_str(), &tr) == 0)
     {
         return std::string();
     }