贡献开源的位操作函数
本帖最后由 test01 于 2012-10-13 02:46 编辑/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
uint64_t read_bit (uint64_t source_bits, uint_fast8_t source_width, uint_fast8_t n)//Lowest order is 0
{
const uint_fast8_t MAXIMUM_WIDTH_BIT = 64;
if ((source_bits >> source_width) not_eq 0)
{
return source_bits;
}
if (source_width > MAXIMUM_WIDTH_BIT)
{
return source_bits;
}
if (n >= source_width)
{
return source_bits;
}
return (source_bits >> n) bitand ((uint64_t)0x01);
}
uint64_t write_bit (uint64_t source_bits, uint_fast8_t source_width, uint_fast8_t n, uint_fast8_t a_bit)//Lowest order is 0
{
const uint_fast8_t MAXIMUM_WIDTH_BIT = 64;
if ((source_bits >> source_width) not_eq 0)
{
return source_bits;
}
if (source_width > MAXIMUM_WIDTH_BIT)
{
return source_bits;
}
if (n >= source_width)
{
return source_bits;
}
if ((a_bit >> 1) not_eq 0)
{
return source_bits;
}
(a_bit == 0) ? (source_bits and_eq (compl(((uint64_t)0x01) << n))) : (source_bits or_eq (((uint64_t)0x01) << n));
return source_bits;
}
uint64_t xor_bit (uint64_t source_bits, uint_fast8_t source_width, uint_fast8_t n, uint_fast8_t a_bit)//Lowest order is 0
{
const uint_fast8_t MAXIMUM_WIDTH_BIT = 64;
if ((source_bits >> source_width) not_eq 0)
{
return source_bits;
}
if (source_width > MAXIMUM_WIDTH_BIT)
{
return source_bits;
}
if (n >= source_width)
{
return source_bits;
}
if ((a_bit >> 1) not_eq 0)
{
return source_bits;
}
return source_bits xor (((uint64_t)a_bit) << n);
}
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纯C11草案标准写的
加了输入参数范围检查
有什么使用问题欢迎留言 为更方便大家应用，变更了开源许可证
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