Don't #define snprintf in VS 2015 or higher.
In VS 2015 and higher snprintf is supplied and therefore vsnprintf
doesn't need to be defined. This also avoids problems caused by
_snprintf being different from snprintf.
This fixes a build break with VS 2015 and improves security.
Originally submitted via chromium by brucedawson@chromium.org
https://codereview.chromium.org/1055603003
Additionally break this MSVC-specific tweak to a new file, which will
become the home of all such MSVC-specific things.
This requires adding a dependency on msvc.h to every example which uses
args.c and tools_common.h
Change-Id: I35b5f8e7ea00f6627403aabc9ea79b0412557a99
diff --git a/vpx_ports/msvc.h b/vpx_ports/msvc.h
new file mode 100644
index 0000000..43a36e7
--- /dev/null
+++ b/vpx_ports/msvc.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2015 The WebM project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef VPX_PORTS_MSVC_H_
+#define VPX_PORTS_MSVC_H_
+#ifdef _MSC_VER
+
+#include "./vpx_config.h"
+
+# if _MSC_VER < 1900 // VS2015 provides snprintf
+# define snprintf _snprintf
+# endif // _MSC_VER < 1900
+
+#endif // _MSC_VER
+#endif // VPX_PORTS_MSVC_H_
