xref: /freebsd/libexec/rtld-elf/rtld_lock.h (revision 3416500aef140042c64bc149cb1ec6620483bc44)
1 /*-
2  * Copyright 2003 Alexander Kabaev.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  *
25  * $FreeBSD$
26  */
27 
28 #ifndef _RTLD_LOCK_H_
29 #define	_RTLD_LOCK_H_
30 
31 #define	RTLI_VERSION	0x01
32 #define	MAX_RTLD_LOCKS	8
33 
34 struct RtldLockInfo
35 {
36 	unsigned int rtli_version;
37 	void *(*lock_create)(void);
38 	void  (*lock_destroy)(void *);
39 	void  (*rlock_acquire)(void *);
40 	void  (*wlock_acquire)(void *);
41 	void  (*lock_release)(void *);
42 	int   (*thread_set_flag)(int);
43 	int   (*thread_clr_flag)(int);
44 	void  (*at_fork)(void);
45 };
46 
47 extern void _rtld_thread_init(struct RtldLockInfo *) __exported;
48 extern void _rtld_atfork_pre(int *) __exported;
49 extern void _rtld_atfork_post(int *) __exported;
50 
51 #ifdef IN_RTLD
52 
53 struct rtld_lock;
54 typedef struct rtld_lock *rtld_lock_t;
55 
56 extern rtld_lock_t	rtld_bind_lock;
57 extern rtld_lock_t	rtld_libc_lock;
58 extern rtld_lock_t	rtld_phdr_lock;
59 
60 #define	RTLD_LOCK_UNLOCKED	0
61 #define	RTLD_LOCK_RLOCKED	1
62 #define	RTLD_LOCK_WLOCKED	2
63 
64 struct Struct_RtldLockState;
65 typedef struct Struct_RtldLockState RtldLockState;
66 
67 void	rlock_acquire(rtld_lock_t, RtldLockState *);
68 void 	wlock_acquire(rtld_lock_t, RtldLockState *);
69 void	lock_release(rtld_lock_t, RtldLockState *);
70 void	lock_upgrade(rtld_lock_t, RtldLockState *);
71 void	lock_restart_for_upgrade(RtldLockState *);
72 
73 #endif	/* IN_RTLD */
74 
75 #endif
76