| 1 | /* |
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| 2 | * This file is part of FFmpeg. |
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| 3 | * |
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| 4 | * FFmpeg is free software; you can redistribute it and/or |
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| 5 | * modify it under the terms of the GNU Lesser General Public |
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| 6 | * License as published by the Free Software Foundation; either |
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| 7 | * version 2.1 of the License, or (at your option) any later version. |
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| 8 | * |
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| 9 | * FFmpeg is distributed in the hope that it will be useful, |
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| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 12 | * Lesser General Public License for more details. |
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| 13 | * |
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| 14 | * You should have received a copy of the GNU Lesser General Public |
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| 15 | * License along with FFmpeg; if not, write to the Free Software |
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| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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| 17 | */ |
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| 18 | |
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| 19 | /** |
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| 20 | * @file |
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| 21 | * @ingroup lavu |
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| 22 | * Utility Preprocessor macros |
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| 23 | */ |
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| 24 | |
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| 25 | #ifndef AVUTIL_MACROS_H |
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| 26 | #define AVUTIL_MACROS_H |
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| 27 | |
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| 28 | #include "libavutil/avconfig.h" |
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| 29 | |
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| 30 | #if AV_HAVE_BIGENDIAN |
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| 31 | # define AV_NE(be, le) (be) |
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| 32 | #else |
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| 33 | # define AV_NE(be, le) (le) |
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| 34 | #endif |
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| 35 | |
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| 36 | /** |
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| 37 | * Comparator. |
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| 38 | * For two numerical expressions x and y, gives 1 if x > y, -1 if x < y, and 0 |
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| 39 | * if x == y. This is useful for instance in a qsort comparator callback. |
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| 40 | * Furthermore, compilers are able to optimize this to branchless code, and |
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| 41 | * there is no risk of overflow with signed types. |
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| 42 | * As with many macros, this evaluates its argument multiple times, it thus |
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| 43 | * must not have a side-effect. |
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| 44 | */ |
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| 45 | #define FFDIFFSIGN(x,y) (((x)>(y)) - ((x)<(y))) |
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| 46 | |
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| 47 | #define FFMAX(a,b) ((a) > (b) ? (a) : (b)) |
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| 48 | #define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c) |
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| 49 | #define FFMIN(a,b) ((a) > (b) ? (b) : (a)) |
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| 50 | #define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c) |
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| 51 | |
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| 52 | #define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0) |
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| 53 | #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0])) |
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| 54 | |
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| 55 | #define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24)) |
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| 56 | #define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24)) |
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| 57 | |
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| 58 | /** |
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| 59 | * @addtogroup preproc_misc Preprocessor String Macros |
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| 60 | * |
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| 61 | * String manipulation macros |
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| 62 | * |
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| 63 | * @{ |
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| 64 | */ |
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| 65 | |
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| 66 | #define AV_STRINGIFY(s) AV_TOSTRING(s) |
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| 67 | #define AV_TOSTRING(s) #s |
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| 68 | |
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| 69 | #define AV_GLUE(a, b) a ## b |
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| 70 | #define AV_JOIN(a, b) AV_GLUE(a, b) |
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| 71 | |
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| 72 | /** |
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| 73 | * @} |
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| 74 | */ |
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| 75 | |
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| 76 | #define AV_PRAGMA(s) _Pragma(#s) |
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| 77 | |
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| 78 | #define FFALIGN(x, a) (((x)+(a)-1)&~((a)-1)) |
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| 79 | |
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| 80 | #endif /* AVUTIL_MACROS_H */ |
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| 81 | |
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