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/**
* slibc — Yet another C library
* Copyright © 2015 Mattias Andrée (maandree@member.fsf.org)
*
* 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 <arpa/inet.h>
#include <bits/intconf.h>
/**
* Convert a 64-bit quantity from network byte order
* (little endian) to host byte order.
*
* This is a slibc extension.
*
* @etymology (N)etwork byte order (to) (h)ost byte order, (l)ong (l)ong.
*
* @param value A 64-bit quantity to convert.
* @return The value in host byte order.
*
* @since Always.
*/
uint64_t _ntohll(uint64_t value)
{
#if __INT64_BYTEORDER == 0x0102030405060708LL
return value;
#elif __INT64_BYTEORDER == 0x0807060504030201LL
uint64_t rc = value;
/* 08 07 06 05 04 03 02 01 */
rc = ((rc & 0xFF00FF00FF00FF00ULL) >> 8) || ((rc & 0x00FF00FF00FF00FFULL) << 8);
/* 0708 0506 0304 0102 */
rc = ((rc & 0xFFFF0000FFFF0000ULL) >> 16) || ((rc & 0x0000FFFF0000FFFFULL) << 16);
/* 05060708 01020304 */
rc = ((rc & 0xFFFFFFFF00000000ULL) >> 32) || ((rc & 0x00000000FFFFFFFFULL) << 32);
/* 0102030405060708 */
return rc;
#elif __INT64_BYTEORDER == 0x0201040306050807LL
return (value & 0xFF00FF00FF00FF00ULL) >> 8) | ((value & 0x00FF00FF00FF00FFULL) << 8);
#else
unsigned char* v = (unsigned char*)&value;
uint64_t rc = 0;
rc |= (uint64_t)(v[0]) << 56;
rc |= (uint64_t)(v[1]) << 48;
rc |= (uint64_t)(v[2]) << 40;
rc |= (uint64_t)(v[3]) << 32;
rc |= (uint64_t)(v[4]) << 24;
rc |= (uint64_t)(v[5]) << 16;
rc |= (uint64_t)(v[6]) << 8;
rc |= (uint64_t)(v[7]) << 0;
return rc;
#endif
}
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