fixed 3 problem that they maybe don't make bug.

src/IO/FileAccess.cpp

@@ -15,6 +15,7 @@ namespace hgl
         {
             fp=-1;
             mode=FileOpenMode::None;
+            hgl_zero(file_state);
         }
 
         FileAccess::~FileAccess()

src/Text/LoadString.cpp

@@ -87,6 +87,9 @@ namespace hgl
      */
     int LoadStringFromText(UTF16String &full_text,const void *source_data,const int size,const CharSet &cs)
     {
+        if(!source_data||size<=0)
+            return(0);
+
         const uint8 *data=(const uint8 *)source_data;
         u16char *str=nullptr;
 

src/Time/DateTime.cpp

@@ -38,6 +38,7 @@ namespace hgl
 
     Time::Time()
     {
+        gmt_off=0;
         hours=0;
         minutes=0;
         seconds=0;
@@ -51,6 +52,7 @@ namespace hgl
 
     Time::Time(int h,int m,int s,int ms)
     {
+        gmt_off=0;
         hours=h;
         minutes=m;
         seconds=s;