| 1 | /* |
| 2 | * arbitrary precision integers |
| 3 | * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at> |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation; either |
| 10 | * version 2.1 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with FFmpeg; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | /** |
| 23 | * @file |
| 24 | * arbitrary precision integers |
| 25 | * @author Michael Niedermayer <michaelni@gmx.at> |
| 26 | */ |
| 27 | |
| 28 | #ifndef AVUTIL_INTEGER_H |
| 29 | #define AVUTIL_INTEGER_H |
| 30 | |
| 31 | #include <stdint.h> |
| 32 | #include "common.h" |
| 33 | |
| 34 | #define AV_INTEGER_SIZE 8 |
| 35 | |
| 36 | typedef struct AVInteger{ |
| 37 | uint16_t v[AV_INTEGER_SIZE]; |
| 38 | } AVInteger; |
| 39 | |
| 40 | AVInteger av_add_i(AVInteger a, AVInteger b) av_const; |
| 41 | AVInteger av_sub_i(AVInteger a, AVInteger b) av_const; |
| 42 | |
| 43 | /** |
| 44 | * Return the rounded-down value of the base 2 logarithm of the given |
| 45 | * AVInteger. This is simply the index of the most significant bit |
| 46 | * which is 1, or 0 if all bits are 0. |
| 47 | */ |
| 48 | int av_log2_i(AVInteger a) av_const; |
| 49 | AVInteger av_mul_i(AVInteger a, AVInteger b) av_const; |
| 50 | |
| 51 | /** |
| 52 | * Return 0 if a==b, 1 if a>b and -1 if a<b. |
| 53 | */ |
| 54 | int av_cmp_i(AVInteger a, AVInteger b) av_const; |
| 55 | |
| 56 | /** |
| 57 | * bitwise shift |
| 58 | * @param s the number of bits by which the value should be shifted right, |
| 59 | may be negative for shifting left |
| 60 | */ |
| 61 | AVInteger av_shr_i(AVInteger a, int s) av_const; |
| 62 | |
| 63 | /** |
| 64 | * Return a % b. |
| 65 | * @param quot a/b will be stored here. |
| 66 | */ |
| 67 | AVInteger av_mod_i(AVInteger *quot, AVInteger a, AVInteger b); |
| 68 | |
| 69 | /** |
| 70 | * Return a/b. |
| 71 | */ |
| 72 | AVInteger av_div_i(AVInteger a, AVInteger b) av_const; |
| 73 | |
| 74 | /** |
| 75 | * Convert the given int64_t to an AVInteger. |
| 76 | */ |
| 77 | AVInteger av_int2i(int64_t a) av_const; |
| 78 | |
| 79 | /** |
| 80 | * Convert the given AVInteger to an int64_t. |
| 81 | * If the AVInteger is too large to fit into an int64_t, |
| 82 | * then only the least significant 64 bits will be used. |
| 83 | */ |
| 84 | int64_t av_i2int(AVInteger a) av_const; |
| 85 | |
| 86 | #endif /* AVUTIL_INTEGER_H */ |