/usr/include/mysql/private/my_bit.h is in libmariadbclient-dev 1:10.1.29-6.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 | /* Copyright (c) 2007, 2011, Oracle and/or its affiliates.
Copyright (c) 2009-2011, Monty Program Ab
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
#ifndef MY_BIT_INCLUDED
#define MY_BIT_INCLUDED
#include <my_global.h>
/*
Some useful bit functions
*/
C_MODE_START
extern const char _my_bits_nbits[256];
extern const uchar _my_bits_reverse_table[256];
/*
Find smallest X in 2^X >= value
This can be used to divide a number with value by doing a shift instead
*/
static inline uint my_bit_log2(ulong value)
{
uint bit;
for (bit=0 ; value > 1 ; value>>=1, bit++) ;
return bit;
}
static inline uint my_count_bits(ulonglong v)
{
#if SIZEOF_LONG_LONG > 4
/* The following code is a bit faster on 16 bit machines than if we would
only shift v */
ulong v2=(ulong) (v >> 32);
return (uint) (uchar) (_my_bits_nbits[(uchar) v] +
_my_bits_nbits[(uchar) (v >> 8)] +
_my_bits_nbits[(uchar) (v >> 16)] +
_my_bits_nbits[(uchar) (v >> 24)] +
_my_bits_nbits[(uchar) (v2)] +
_my_bits_nbits[(uchar) (v2 >> 8)] +
_my_bits_nbits[(uchar) (v2 >> 16)] +
_my_bits_nbits[(uchar) (v2 >> 24)]);
#else
return (uint) (uchar) (_my_bits_nbits[(uchar) v] +
_my_bits_nbits[(uchar) (v >> 8)] +
_my_bits_nbits[(uchar) (v >> 16)] +
_my_bits_nbits[(uchar) (v >> 24)]);
#endif
}
static inline uint my_count_bits_uint32(uint32 v)
{
return (uint) (uchar) (_my_bits_nbits[(uchar) v] +
_my_bits_nbits[(uchar) (v >> 8)] +
_my_bits_nbits[(uchar) (v >> 16)] +
_my_bits_nbits[(uchar) (v >> 24)]);
}
/*
Next highest power of two
SYNOPSIS
my_round_up_to_next_power()
v Value to check
RETURN
Next or equal power of 2
Note: 0 will return 0
NOTES
Algorithm by Sean Anderson, according to:
http://graphics.stanford.edu/~seander/bithacks.html
(Orignal code public domain)
Comments shows how this works with 01100000000000000000000000001011
*/
static inline uint32 my_round_up_to_next_power(uint32 v)
{
v--; /* 01100000000000000000000000001010 */
v|= v >> 1; /* 01110000000000000000000000001111 */
v|= v >> 2; /* 01111100000000000000000000001111 */
v|= v >> 4; /* 01111111110000000000000000001111 */
v|= v >> 8; /* 01111111111111111100000000001111 */
v|= v >> 16; /* 01111111111111111111111111111111 */
return v+1; /* 10000000000000000000000000000000 */
}
static inline uint32 my_clear_highest_bit(uint32 v)
{
uint32 w=v >> 1;
w|= w >> 1;
w|= w >> 2;
w|= w >> 4;
w|= w >> 8;
w|= w >> 16;
return v & w;
}
static inline uint32 my_reverse_bits(uint32 key)
{
return
(_my_bits_reverse_table[ key & 255] << 24) |
(_my_bits_reverse_table[(key>> 8) & 255] << 16) |
(_my_bits_reverse_table[(key>>16) & 255] << 8) |
_my_bits_reverse_table[(key>>24) ];
}
/*
a number with the n lowest bits set
an overflow-safe version of (1 << n) - 1
*/
static inline uint32 my_set_bits(int n)
{
return (((1UL << (n - 1)) - 1) << 1) | 1;
}
C_MODE_END
#endif /* MY_BIT_INCLUDED */
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