Add ffmpeg externals

Externals/ffmpeg/include/libavutil/avassert.h

@@ -0,0 +1,66 @@
+/*
+ * copyright (c) 2010 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * simple assert() macros that are a bit more flexible than ISO C assert().
+ * @author Michael Niedermayer <michaelni@gmx.at>
+ */
+
+#ifndef AVUTIL_AVASSERT_H
+#define AVUTIL_AVASSERT_H
+
+#include <stdlib.h>
+#include "avutil.h"
+#include "log.h"
+
+/**
+ * assert() equivalent, that is always enabled.
+ */
+#define av_assert0(cond) do {                                           \
+    if (!(cond)) {                                                      \
+        av_log(NULL, AV_LOG_PANIC, "Assertion %s failed at %s:%d\n",    \
+               AV_STRINGIFY(cond), __FILE__, __LINE__);                 \
+        abort();                                                        \
+    }                                                                   \
+} while (0)
+
+
+/**
+ * assert() equivalent, that does not lie in speed critical code.
+ * These asserts() thus can be enabled without fearing speedloss.
+ */
+#if defined(ASSERT_LEVEL) && ASSERT_LEVEL > 0
+#define av_assert1(cond) av_assert0(cond)
+#else
+#define av_assert1(cond) ((void)0)
+#endif
+
+
+/**
+ * assert() equivalent, that does lie in speed critical code.
+ */
+#if defined(ASSERT_LEVEL) && ASSERT_LEVEL > 1
+#define av_assert2(cond) av_assert0(cond)
+#else
+#define av_assert2(cond) ((void)0)
+#endif
+
+#endif /* AVUTIL_AVASSERT_H */