xref: /freebsd/include/dlfcn.h (revision 4c8945a06b01a5c8122cdeb402af36bb46a06acc)
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. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #ifndef _DLFCN_H_
33 #define	_DLFCN_H_
34 
35 #include <sys/_types.h>
36 
37 /*
38  * Modes and flags for dlopen().
39  */
40 #define	RTLD_LAZY	1	/* Bind function calls lazily. */
41 #define	RTLD_NOW	2	/* Bind function calls immediately. */
42 #define	RTLD_MODEMASK	0x3
43 #define	RTLD_GLOBAL	0x100	/* Make symbols globally available. */
44 #define	RTLD_LOCAL	0	/* Opposite of RTLD_GLOBAL, and the default. */
45 #define	RTLD_TRACE	0x200	/* Trace loaded objects and exit. */
46 #define	RTLD_NODELETE	0x01000	/* Do not remove members. */
47 #define	RTLD_NOLOAD	0x02000	/* Do not load if not already loaded. */
48 
49 /*
50  * Request arguments for dlinfo().
51  */
52 #define	RTLD_DI_LINKMAP		2	/* Obtain link map. */
53 #define	RTLD_DI_SERINFO		4	/* Obtain search path info. */
54 #define	RTLD_DI_SERINFOSIZE	5	/*  ... query for required space. */
55 #define	RTLD_DI_ORIGIN		6	/* Obtain object origin */
56 #define	RTLD_DI_MAX		RTLD_DI_ORIGIN
57 
58 /*
59  * Special handle arguments for dlsym()/dlinfo().
60  */
61 #define	RTLD_NEXT	((void *) -1)	/* Search subsequent objects. */
62 #define	RTLD_DEFAULT	((void *) -2)	/* Use default search algorithm. */
63 #define	RTLD_SELF	((void *) -3)	/* Search the caller itself. */
64 
65 #if __BSD_VISIBLE
66 
67 #ifndef	_SIZE_T_DECLARED
68 typedef __size_t        size_t;
69 #define	_SIZE_T_DECLARED
70 #endif
71 
72 /*
73  * Structure filled in by dladdr().
74  */
75 typedef	struct dl_info {
76 	const char	*dli_fname;	/* Pathname of shared object. */
77 	void		*dli_fbase;	/* Base address of shared object. */
78 	const char	*dli_sname;	/* Name of nearest symbol. */
79 	void		*dli_saddr;	/* Address of nearest symbol. */
80 } Dl_info;
81 
82 /*-
83  * The actual type declared by this typedef is immaterial, provided that
84  * it is a function pointer.  Its purpose is to provide a return type for
85  * dlfunc() which can be cast to a function pointer type without depending
86  * on behavior undefined by the C standard, which might trigger a compiler
87  * diagnostic.  We intentionally declare a unique type signature to force
88  * a diagnostic should the application not cast the return value of dlfunc()
89  * appropriately.
90  */
91 struct __dlfunc_arg {
92 	int	__dlfunc_dummy;
93 };
94 
95 typedef	void (*dlfunc_t)(struct __dlfunc_arg);
96 
97 /*
98  * Structures, returned by the RTLD_DI_SERINFO dlinfo() request.
99  */
100 typedef struct dl_serpath {
101 	char *		dls_name;	/* single search path entry */
102 	unsigned int	dls_flags;	/* path information */
103 } Dl_serpath;
104 
105 typedef struct  dl_serinfo {
106         size_t		dls_size;       /* total buffer size */
107         unsigned int	dls_cnt;        /* number of path entries */
108         Dl_serpath	dls_serpath[1]; /* there may be more than one */
109 } Dl_serinfo;
110 
111 #endif /* __BSD_VISIBLE */
112 
113 __BEGIN_DECLS
114 /* XSI functions first. */
115 int	 dlclose(void *);
116 char	*dlerror(void);
117 void	*dlopen(const char *, int);
118 void	*dlsym(void * __restrict, const char * __restrict);
119 
120 #if __BSD_VISIBLE
121 int	 dladdr(const void * __restrict, Dl_info * __restrict);
122 dlfunc_t dlfunc(void * __restrict, const char * __restrict);
123 int	 dlinfo(void * __restrict, int, void * __restrict);
124 void	 dllockinit(void *_context,
125 	    void *(*_lock_create)(void *_context),
126 	    void (*_rlock_acquire)(void *_lock),
127 	    void (*_wlock_acquire)(void *_lock),
128 	    void (*_lock_release)(void *_lock),
129 	    void (*_lock_destroy)(void *_lock),
130 	    void (*_context_destroy)(void *_context));
131 void	*dlvsym(void * __restrict, const char * __restrict,
132 	    const char * __restrict);
133 #endif /* __BSD_VISIBLE */
134 __END_DECLS
135 
136 #endif /* !_DLFCN_H_ */
137