xref: /freebsd/include/dlfcn.h (revision fda2301943c10ee6e10a1c26d835bbff867adc1a)
1 /*
2  * Copyright (c) 1994
3  *	The Regents of the University of California.  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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * $FreeBSD$
34  */
35 
36 #ifndef _DLFCN_H_
37 #define	_DLFCN_H_
38 #include <sys/cdefs.h>
39 
40 /*
41  * Modes and flags for dlopen().
42  */
43 #define RTLD_LAZY	1	/* Bind function calls lazily */
44 #define RTLD_NOW	2	/* Bind function calls immediately */
45 #define RTLD_MODEMASK	0x3
46 #define RTLD_GLOBAL	0x100	/* Make symbols globally available */
47 #define RTLD_LOCAL	0	/* Opposite of RTLD_GLOBAL, and the default */
48 #define RTLD_TRACE	0x200	/* Trace loaded objects and exit */
49 
50 /*
51  * Special handle arguments for dlsym().
52  */
53 #define RTLD_NEXT	((void *) -1)	/* Search subsequent objects */
54 #define RTLD_DEFAULT	((void *) -2)	/* Use default search algorithm */
55 
56 /*
57  * Structure filled in by dladdr().
58  */
59 typedef struct dl_info {
60 	const char	*dli_fname;	/* Pathname of shared object */
61 	void		*dli_fbase;	/* Base address of shared object */
62 	const char	*dli_sname;	/* Name of nearest symbol */
63 	void		*dli_saddr;	/* Address of nearest symbol */
64 } Dl_info;
65 
66 /*
67  * The actual type declared by this typedef is immaterial, provided that
68  * it is a function pointer.  Its purpose is to provide a return type for
69  * dlfunc() which can be cast to a function pointer type without depending
70  * on behavior undefined by the C standard, which might trigger a compiler
71  * diagnostic.  We intentionally declare a unique type signature to force
72  * a diagnostic should the application not cast the return value of dlfunc()
73  * appropriately.
74  */
75 struct __dlfunc_arg {
76 	int __dlfunc_dummy;
77 };
78 
79 typedef void (*dlfunc_t)(struct __dlfunc_arg);
80 
81 __BEGIN_DECLS
82 /* XSI functions first */
83 int dlclose(void *);
84 const char *dlerror(void);
85 void *dlopen(const char *, int);
86 void *dlsym(void * /* __restrict */, const char * /* __restrict */);
87 
88 #if __BSD_VISIBLE
89 int dladdr(const void *, Dl_info *);
90 dlfunc_t dlfunc(void * /* __restrict */, const char * /* __restrict */);
91 void dllockinit(void *_context,
92 		void *(*_lock_create)(void *_context),
93 		void (*_rlock_acquire)(void *_lock),
94 		void (*_wlock_acquire)(void *_lock),
95 		void (*_lock_release)(void *_lock),
96 		void (*_lock_destroy)(void *_lock),
97 		void (*_context_destroy)(void *_context));
98 #endif /* __BSD_VISIBLE */
99 __END_DECLS
100 
101 #endif /* !_DLFCN_H_ */
102