1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1999 Marcel Moolenaar 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer 12 * in this position and unchanged. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 * 30 * $FreeBSD$ 31 */ 32 33 #ifndef _SYS_ASSYM_H_ 34 #define _SYS_ASSYM_H_ 35 36 #define ASSYM_BIAS 0x10000 /* avoid zero-length arrays */ 37 #define ASSYM_ABS(value) ((value) < 0 ? -((value) + 1) + 1ULL : (value)) 38 39 #define ASSYM(name, value) \ 40 char name ## sign[((value) < 0 ? 1 : 0) + ASSYM_BIAS]; \ 41 char name ## w0[(ASSYM_ABS(value) & 0xFFFFU) + ASSYM_BIAS]; \ 42 char name ## w1[((ASSYM_ABS(value) & 0xFFFF0000UL) >> 16) + ASSYM_BIAS]; \ 43 char name ## w2[((ASSYM_ABS(value) & 0xFFFF00000000ULL) >> 32) + ASSYM_BIAS]; \ 44 char name ## w3[((ASSYM_ABS(value) & 0xFFFF000000000000ULL) >> 48) + ASSYM_BIAS] 45 46 47 /* char name ## _datatype_ ## STRINGIFY(typeof(((struct parenttype *)(0x0))-> name)) [1]; */ 48 #ifdef OFFSET_TEST 49 #define OFFSET_CTASSERT CTASSERT 50 #else 51 #define OFFSET_CTASSERT(...) 52 #endif 53 54 #define OFFSYM(name, parenttype, datatype) \ 55 ASSYM(name, offsetof(struct parenttype, name)); \ 56 char name ## _datatype_ ## datatype [1]; \ 57 char name ## _parenttype_ ## parenttype [1]; \ 58 CTASSERT(__builtin_types_compatible_p(__typeof(((struct parenttype *)(0x0))-> name), datatype)); \ 59 OFFSET_CTASSERT(offsetof(struct parenttype, name) == offsetof(struct parenttype ## _lite, name)) 60 61 #endif /* !_SYS_ASSYM_H_ */ 62