minimodem-mirror/src/misc.c

47 lines
1.3 KiB
C
Executable File

/*
* misc.c
*
* Copyright (C) 2014 Marcos Vives Del Sol <socram8888@gmail.com>
*
* 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, either version 3 of the License, or
* (at your option) any later version.
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include "misc.h"
// Reverses the ordering of the bits on an integer
unsigned long long
bit_reverse(unsigned long long value,
unsigned int bits)
{
unsigned int out = 0;
while (bits--) {
out = (out << 1) | (value & 1);
value >>= 1;
}
return out;
}
// Gets "bits" bits from "value" starting "offset" bits from the start
unsigned long long
bit_window(unsigned long long value,
unsigned int offset,
unsigned int bits)
{
unsigned long long mask = (1ULL << bits) - 1;
value = (value >> offset) & mask;
return value;
}