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- /*
- * 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
- * @ingroup lavu
- * Utility Preprocessor macros
- */
-
- #ifndef AVUTIL_MACROS_H
- #define AVUTIL_MACROS_H
-
- #include "libavutil/avconfig.h"
-
- #if AV_HAVE_BIGENDIAN
- # define AV_NE(be, le) (be)
- #else
- # define AV_NE(be, le) (le)
- #endif
-
- /**
- * Comparator.
- * For two numerical expressions x and y, gives 1 if x > y, -1 if x < y, and 0
- * if x == y. This is useful for instance in a qsort comparator callback.
- * Furthermore, compilers are able to optimize this to branchless code, and
- * there is no risk of overflow with signed types.
- * As with many macros, this evaluates its argument multiple times, it thus
- * must not have a side-effect.
- */
- #define FFDIFFSIGN(x,y) (((x)>(y)) - ((x)<(y)))
-
- #define FFMAX(a,b) ((a) > (b) ? (a) : (b))
- #define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c)
- #define FFMIN(a,b) ((a) > (b) ? (b) : (a))
- #define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c)
-
- #define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)
- #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0]))
-
- #define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24))
- #define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24))
-
- /**
- * @addtogroup preproc_misc Preprocessor String Macros
- *
- * String manipulation macros
- *
- * @{
- */
-
- #define AV_STRINGIFY(s) AV_TOSTRING(s)
- #define AV_TOSTRING(s) #s
-
- #define AV_GLUE(a, b) a ## b
- #define AV_JOIN(a, b) AV_GLUE(a, b)
-
- /**
- * @}
- */
-
- #define AV_PRAGMA(s) _Pragma(#s)
-
- #define FFALIGN(x, a) (((x)+(a)-1)&~((a)-1))
-
- #endif /* AVUTIL_MACROS_H */
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