Avoid an undefined behavior of memcpy() in gzappend().

[zlib.git] / gzguts.h

diff --git a/gzguts.h b/gzguts.h
index 593dfee1111af630e02d37c6f6641ffabe40f45d..6378d468a258b134420c2434f62de8f0d3fb42ea 100644 (file)
--- a/gzguts.h
+++ b/gzguts.h
@@ -1,5 +1,5 @@
 /* gzguts.h -- zlib internal header definitions for gz* operations
- * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013 Mark Adler
+ * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013, 2016 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
@@ -39,6 +39,10 @@
 #  include <io.h>
 #endif
 
+#if defined(_WIN32)
+#  define WIDECHAR
+#endif
+
 #ifdef WINAPI_FAMILY
 #  define open _open
 #  define read _read
@@ -99,18 +103,19 @@
 #  endif
 #endif
 
-/* unlike snprintf (which is required in C99, yet still not supported by
-   Microsoft more than a decade later!), _snprintf does not guarantee null
-   termination of the result -- however this is only used in gzlib.c where
+/* unlike snprintf (which is required in C99), _snprintf does not guarantee
+   null termination of the result -- however this is only used in gzlib.c where
    the result is assured to fit in the space provided */
-#ifdef _MSC_VER
+#if defined(_MSC_VER) && _MSC_VER < 1900
 #  define snprintf _snprintf
 #endif
 
 #ifndef local
 #  define local static
 #endif
-/* compile with -Dlocal if your debugger can't find static symbols */
+/* since "static" is used to mean two completely different things in C, we
+   define "local" for the non-static meaning of "static", for readability
+   (compile with -Dlocal if your debugger can't find static symbols) */
 
 /* gz* functions always use library allocation functions */
 #ifndef STDC