1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright 2003 Alexander Kabaev.
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 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#ifndef _RTLD_LOCK_H_
29#define	_RTLD_LOCK_H_
30
31#define	RTLI_VERSION_ONE	0x01
32#define	RTLI_VERSION		0x02
33
34#define	MAX_RTLD_LOCKS	8
35
36/*
37 * This structure is part of the ABI between rtld and threading
38 * libraries, like libthr and even libc_r.  Its layout is fixed and
39 * can be changed only by appending new fields at the end, with the
40 * bump of RTLI_VERSION.
41 */
42struct RtldLockInfo
43{
44	/*
45	 * Valid if the object calling _rtld_thread_init() exported
46	 * symbol _pli_rtli_version.  Otherwise assume RTLI_VERSION_ONE.
47	 */
48	unsigned int rtli_version;
49
50	void *(*lock_create)(void);
51	void  (*lock_destroy)(void *);
52	void  (*rlock_acquire)(void *);
53	void  (*wlock_acquire)(void *);
54	void  (*lock_release)(void *);
55	int   (*thread_set_flag)(int);
56	int   (*thread_clr_flag)(int);
57	void  (*at_fork)(void);
58
59	/* Version 2 fields */
60	char *(*dlerror_loc)(void);
61	int  *(*dlerror_seen)(void);
62	int   dlerror_loc_sz;
63};
64
65#if defined(IN_RTLD) || defined(PTHREAD_KERNEL)
66
67void _rtld_thread_init(struct RtldLockInfo *) __exported;
68void _rtld_atfork_pre(int *) __exported;
69void _rtld_atfork_post(int *) __exported;
70
71#endif /* IN_RTLD || PTHREAD_KERNEL */
72
73#ifdef IN_RTLD
74
75struct rtld_lock;
76typedef struct rtld_lock *rtld_lock_t;
77
78extern rtld_lock_t	rtld_bind_lock;
79extern rtld_lock_t	rtld_libc_lock;
80extern rtld_lock_t	rtld_phdr_lock;
81
82extern struct RtldLockInfo lockinfo;
83
84#define	RTLD_LOCK_UNLOCKED	0
85#define	RTLD_LOCK_RLOCKED	1
86#define	RTLD_LOCK_WLOCKED	2
87
88struct Struct_RtldLockState;
89typedef struct Struct_RtldLockState RtldLockState;
90
91void	rlock_acquire(rtld_lock_t, RtldLockState *);
92void 	wlock_acquire(rtld_lock_t, RtldLockState *);
93void	lock_release(rtld_lock_t, RtldLockState *);
94void	lock_upgrade(rtld_lock_t, RtldLockState *);
95void	lock_restart_for_upgrade(RtldLockState *);
96
97void	dlerror_dflt_init(void);
98
99#endif	/* IN_RTLD */
100
101#endif
102