fixes for MSVC non-standard C library

strcase => _stricmp
strncase => _strnicmp
strdup => _strdup
snprintf => _snprintf

a compliant snprintf() is supposed to be available
in MS Visual Studio 2015 and later

src/readini.c

@@ -29,6 +29,9 @@
 #include <string.h>
 #include <stdlib.h>
 #include <ctype.h>
+#if defined(_MSC_VER)
+#define strdup _strdup
+#endif
 
 #include "const.h"
 #include "errors.h"