1/***************************************************************************** 2 3Copyright (c) 1994, 2009, Oracle and/or its affiliates. All Rights Reserved. 4 5This program is free software; you can redistribute it and/or modify 6it under the terms of the GNU General Public License, version 2.0, 7as published by the Free Software Foundation. 8 9This program is also distributed with certain software (including 10but not limited to OpenSSL) that is licensed under separate terms, 11as designated in a particular file or component or in included license 12documentation. The authors of MySQL hereby grant you an additional 13permission to link the program and your derivative works with the 14separately licensed software that they have included with MySQL. 15 16This program is distributed in the hope that it will be useful, 17but WITHOUT ANY WARRANTY; without even the implied warranty of 18MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19GNU General Public License, version 2.0, for more details. 20 21You should have received a copy of the GNU General Public License along with 22this program; if not, write to the Free Software Foundation, Inc., 2351 Franklin Street, Suite 500, Boston, MA 02110-1335 USA 24 25*****************************************************************************/ 26 27/**************************************************************//** 28@file include/ut0byte.ic 29Utilities for byte operations 30 31Created 5/30/1994 Heikki Tuuri 32*******************************************************************/ 33 34/*******************************************************//** 35Creates a 64-bit integer out of two 32-bit integers. 36@return created integer */ 37UNIV_INLINE 38ib_uint64_t 39ut_ull_create( 40/*==========*/ 41 ulint high, /*!< in: high-order 32 bits */ 42 ulint low) /*!< in: low-order 32 bits */ 43{ 44 ut_ad(high <= ULINT32_MASK); 45 ut_ad(low <= ULINT32_MASK); 46 return(((ib_uint64_t) high) << 32 | low); 47} 48 49/********************************************************//** 50Rounds a 64-bit integer downward to a multiple of a power of 2. 51@return rounded value */ 52UNIV_INLINE 53ib_uint64_t 54ut_uint64_align_down( 55/*=================*/ 56 ib_uint64_t n, /*!< in: number to be rounded */ 57 ulint align_no) /*!< in: align by this number 58 which must be a power of 2 */ 59{ 60 ut_ad(align_no > 0); 61 ut_ad(ut_is_2pow(align_no)); 62 63 return(n & ~((ib_uint64_t) align_no - 1)); 64} 65 66/********************************************************//** 67Rounds ib_uint64_t upward to a multiple of a power of 2. 68@return rounded value */ 69UNIV_INLINE 70ib_uint64_t 71ut_uint64_align_up( 72/*===============*/ 73 ib_uint64_t n, /*!< in: number to be rounded */ 74 ulint align_no) /*!< in: align by this number 75 which must be a power of 2 */ 76{ 77 ib_uint64_t align_1 = (ib_uint64_t) align_no - 1; 78 79 ut_ad(align_no > 0); 80 ut_ad(ut_is_2pow(align_no)); 81 82 return((n + align_1) & ~align_1); 83} 84 85/*********************************************************//** 86The following function rounds up a pointer to the nearest aligned address. 87@return aligned pointer */ 88UNIV_INLINE 89void* 90ut_align( 91/*=====*/ 92 const void* ptr, /*!< in: pointer */ 93 ulint align_no) /*!< in: align by this number */ 94{ 95 ut_ad(align_no > 0); 96 ut_ad(((align_no - 1) & align_no) == 0); 97 ut_ad(ptr); 98 99 ut_ad(sizeof(void*) == sizeof(ulint)); 100 101 return((void*)((((ulint) ptr) + align_no - 1) & ~(align_no - 1))); 102} 103 104/*********************************************************//** 105The following function rounds down a pointer to the nearest 106aligned address. 107@return aligned pointer */ 108UNIV_INLINE 109void* 110ut_align_down( 111/*==========*/ 112 const void* ptr, /*!< in: pointer */ 113 ulint align_no) /*!< in: align by this number */ 114{ 115 ut_ad(align_no > 0); 116 ut_ad(((align_no - 1) & align_no) == 0); 117 ut_ad(ptr); 118 119 ut_ad(sizeof(void*) == sizeof(ulint)); 120 121 return((void*)((((ulint) ptr)) & ~(align_no - 1))); 122} 123 124/*********************************************************//** 125The following function computes the offset of a pointer from the nearest 126aligned address. 127@return distance from aligned pointer */ 128UNIV_INLINE 129ulint 130ut_align_offset( 131/*============*/ 132 const void* ptr, /*!< in: pointer */ 133 ulint align_no) /*!< in: align by this number */ 134{ 135 ut_ad(align_no > 0); 136 ut_ad(((align_no - 1) & align_no) == 0); 137 ut_ad(ptr); 138 139 ut_ad(sizeof(void*) == sizeof(ulint)); 140 141 return(((ulint) ptr) & (align_no - 1)); 142} 143 144/*****************************************************************//** 145Gets the nth bit of a ulint. 146@return TRUE if nth bit is 1; 0th bit is defined to be the least significant */ 147UNIV_INLINE 148ibool 149ut_bit_get_nth( 150/*===========*/ 151 ulint a, /*!< in: ulint */ 152 ulint n) /*!< in: nth bit requested */ 153{ 154 ut_ad(n < 8 * sizeof(ulint)); 155#if TRUE != 1 156# error "TRUE != 1" 157#endif 158 return(1 & (a >> n)); 159} 160 161/*****************************************************************//** 162Sets the nth bit of a ulint. 163@return the ulint with the bit set as requested */ 164UNIV_INLINE 165ulint 166ut_bit_set_nth( 167/*===========*/ 168 ulint a, /*!< in: ulint */ 169 ulint n, /*!< in: nth bit requested */ 170 ibool val) /*!< in: value for the bit to set */ 171{ 172 ut_ad(n < 8 * sizeof(ulint)); 173#if TRUE != 1 174# error "TRUE != 1" 175#endif 176 if (val) { 177 return(((ulint) 1 << n) | a); 178 } else { 179 return(~((ulint) 1 << n) & a); 180 } 181} 182