Don't use strftime

Author: uNetworkingAB

src/LoopData.h

@@ -68,7 +68,21 @@ struct alignas(16) LoopData {
 #else
         gmtime_r(&now, &tstruct);
 #endif
-        strftime(date, 32, "%a, %d %b %Y %X GMT", &tstruct);
+        static const char wday_name[][4] = {
+            "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
+        };
+        static const char mon_name[][4] = {
+            "Jan", "Feb", "Mar", "Apr", "May", "Jun",
+            "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
+        };
+        sprintf(date, "%.3s, %.2d %.3s %d %.2d:%.2d:%.2d GMT",
+            wday_name[tstruct.tm_wday],
+            tstruct.tm_mday,
+            mon_name[tstruct.tm_mon],
+            1900 + tstruct.tm_year,
+            tstruct.tm_hour,
+            tstruct.tm_min,
+            tstruct.tm_sec);
     }
 
     char date[32];