1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26#ifndef	_SGSRTCID_H
27#define	_SGSRTCID_H
28
29#pragma ident	"%Z%%M%	%I%	%E% SMI"
30
31#ifdef	__cplusplus
32extern "C" {
33#endif
34
35
36/*
37 * This file defines the Rtc_id structure that is found at the beginning
38 * of linker configuration files. It resides at this level so that
39 * it can be accessed by file(1) as well as by crle(1) and the
40 * runtime linker (ld.so.1). The rest of the data structures for
41 * config files are found in usr/src/cmd/sgs/include/rtc.h
42 *
43 * The use of sizeof(char) data (no byte order issue) and explicit
44 * padding in the definition of Rtc_id ensures that it will have
45 * exactly the same layout on all systems, and will have a
46 * size of 16 bytes. The same layout means all systems can read it.
47 * the same size means that any data can be safely placed immediately
48 * following it, without the need for alignment.
49 */
50
51/*
52 * Identification header.
53 */
54typedef struct {
55	uchar_t	id_magic0;	/* RTC_ID_MAG0 */
56	uchar_t	id_magic1;	/* RTC_ID_MAG1 */
57	uchar_t	id_magic2;	/* RTC_ID_MAG2 */
58	uchar_t	id_magic3;	/* RTC_ID_MAG0 */
59	uchar_t	id_class;	/* File class/capacity (ELFCLASS constant) */
60	uchar_t	id_data;	/* Data encoding (ELFDATA constant) */
61	uchar_t	id_machine;	/* Architecture (ELF EM_ constant) */
62	uchar_t	id_pad[9];	/* Ensure size is 16 bytes */
63} Rtc_id;
64
65#define	RTC_ID_MAG0 '\077'	/* ? */
66#define	RTC_ID_MAG1 'R'		/* Runtime */
67#define	RTC_ID_MAG2 'L'		/* Linker */
68#define	RTC_ID_MAG3 'C'		/* Configuration */
69
70/*
71 * Ensure that the largest machine constant will not grow beyond
72 * maximum value representable by an unsigned byte without our
73 * being alerted to it.
74 */
75#if EM_NUM > 256
76#error "Maximum machine constant size exceeded. Format requires revision."
77#endif
78
79/*
80 * Check the 4 bytes starting at the given address to see if
81 * they contain the Rtc_id magic number. The type of the address
82 * is unimportant as long as it is valid, because RTC_ID_TEST()
83 * will cast it to (uchar_t *).
84 */
85#define	RTC_ID_TEST(addr) \
86	((RTC_ID_MAG0 == *((uchar_t *)addr)) && \
87	(RTC_ID_MAG1 == *(((uchar_t *)addr) + 1)) && \
88	(RTC_ID_MAG2 == *(((uchar_t *)addr) + 2)) && \
89	(RTC_ID_MAG3 == *(((uchar_t *)addr) + 3)))
90
91#ifdef	__cplusplus
92}
93#endif
94
95#endif	/* _SGSRTCID_H */
96