1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 * $FreeBSD$
28 */
29
30#ifndef _RTLD_LOCK_H_
31#define	_RTLD_LOCK_H_
32
33#define	RTLI_VERSION_ONE	0x01
34#define	RTLI_VERSION		0x02
35
36#define	MAX_RTLD_LOCKS	8
37
38/*
39 * This structure is part of the ABI between rtld and threading
40 * libraries, like libthr and even libc_r.  Its layout is fixed and
41 * can be changed only by appending new fields at the end, with the
42 * bump of RTLI_VERSION.
43 */
44struct RtldLockInfo
45{
46	/*
47	 * Valid if the object calling _rtld_thread_init() exported
48	 * symbol _pli_rtli_version.  Otherwise assume RTLI_VERSION_ONE.
49	 */
50	unsigned int rtli_version;
51
52	void *(*lock_create)(void);
53	void  (*lock_destroy)(void *);
54	void  (*rlock_acquire)(void *);
55	void  (*wlock_acquire)(void *);
56	void  (*lock_release)(void *);
57	int   (*thread_set_flag)(int);
58	int   (*thread_clr_flag)(int);
59	void  (*at_fork)(void);
60
61	/* Version 2 fields */
62	char *(*dlerror_loc)(void);
63	int  *(*dlerror_seen)(void);
64	int   dlerror_loc_sz;
65};
66
67#if defined(IN_RTLD) || defined(PTHREAD_KERNEL)
68
69void _rtld_thread_init(struct RtldLockInfo *) __exported;
70void _rtld_atfork_pre(int *) __exported;
71void _rtld_atfork_post(int *) __exported;
72
73#endif /* IN_RTLD || PTHREAD_KERNEL */
74
75#ifdef IN_RTLD
76
77struct rtld_lock;
78typedef struct rtld_lock *rtld_lock_t;
79
80extern rtld_lock_t	rtld_bind_lock;
81extern rtld_lock_t	rtld_libc_lock;
82extern rtld_lock_t	rtld_phdr_lock;
83
84extern struct RtldLockInfo lockinfo;
85
86#define	RTLD_LOCK_UNLOCKED	0
87#define	RTLD_LOCK_RLOCKED	1
88#define	RTLD_LOCK_WLOCKED	2
89
90struct Struct_RtldLockState;
91typedef struct Struct_RtldLockState RtldLockState;
92
93void	rlock_acquire(rtld_lock_t, RtldLockState *);
94void 	wlock_acquire(rtld_lock_t, RtldLockState *);
95void	lock_release(rtld_lock_t, RtldLockState *);
96void	lock_upgrade(rtld_lock_t, RtldLockState *);
97void	lock_restart_for_upgrade(RtldLockState *);
98
99void	dlerror_dflt_init(void);
100
101#endif	/* IN_RTLD */
102
103#endif
104