blob: 2348e436dd4e007e4ca3205548a3141726f322a7 [file] [log] [blame]
lh9ed821d2023-04-07 01:36:19 -07001/* User functions for run-time dynamic loading.
2 Copyright (C) 1995-1999,2000,2001,2003,2004,2006
3 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19 02111-1307 USA. */
20
21#ifndef _DLFCN_H
22#define _DLFCN_H 1
23
24#include <features.h>
25#define __need_size_t
26#include <stddef.h>
27
28/* Collect various system dependent definitions and declarations. */
29#include <bits/dlfcn.h>
30
31
32#ifdef __USE_GNU
33/* If the first argument of `dlsym' or `dlvsym' is set to RTLD_NEXT
34 the run-time address of the symbol called NAME in the next shared
35 object is returned. The "next" relation is defined by the order
36 the shared objects were loaded. */
37# define RTLD_NEXT ((void *) -1l)
38
39/* If the first argument to `dlsym' or `dlvsym' is set to RTLD_DEFAULT
40 the run-time address of the symbol called NAME in the global scope
41 is returned. */
42# define RTLD_DEFAULT ((void *) 0)
43
44
45# if 0 /* uClibc doesnt support this */
46/* Type for namespace indeces. */
47typedef long int Lmid_t;
48
49/* Special namespace ID values. */
50# define LM_ID_BASE 0 /* Initial namespace. */
51# define LM_ID_NEWLM -1 /* For dlmopen: request new namespace. */
52# endif
53#endif
54
55__BEGIN_DECLS
56
57/* Open the shared object FILE and map it in; return a handle that can be
58 passed to `dlsym' to get symbol values from it. */
59extern void *dlopen (__const char *__file, int __mode) __THROW;
60
61/* Unmap and close a shared object opened by `dlopen'.
62 The handle cannot be used again after calling `dlclose'. */
63extern int dlclose (void *__handle) __THROW __nonnull ((1));
64
65/* Find the run-time address in the shared object HANDLE refers to
66 of the symbol called NAME. */
67extern void *dlsym (void *__restrict __handle,
68 __const char *__restrict __name) __THROW __nonnull ((2));
69
70#if 0 /*def __USE_GNU*/
71/* Like `dlopen', but request object to be allocated in a new namespace. */
72extern void *dlmopen (Lmid_t __nsid, __const char *__file, int __mode) __THROW;
73
74/* Find the run-time address in the shared object HANDLE refers to
75 of the symbol called NAME with VERSION. */
76extern void *dlvsym (void *__restrict __handle,
77 __const char *__restrict __name,
78 __const char *__restrict __version)
79 __THROW __nonnull ((2, 3));
80#endif
81
82/* When any of the above functions fails, call this function
83 to return a string describing the error. Each call resets
84 the error string so that a following call returns null. */
85extern char *dlerror (void) __THROW;
86
87
88#ifdef __USE_GNU
89/* Structure containing information about object searched using
90 `dladdr'. */
91typedef struct
92{
93 __const char *dli_fname; /* File name of defining object. */
94 void *dli_fbase; /* Load address of that object. */
95 __const char *dli_sname; /* Name of nearest symbol. */
96 void *dli_saddr; /* Exact value of nearest symbol. */
97} Dl_info;
98
99/* Fill in *INFO with the following information about ADDRESS.
100 Returns 0 iff no shared object's segments contain that address. */
101extern int dladdr (__const void *__address, Dl_info *__info)
102 __THROW __nonnull ((2));
103
104#if 0 /* not supported by uClibc */
105/* Same as `dladdr', but additionally sets *EXTRA_INFO according to FLAGS. */
106extern int dladdr1 (__const void *__address, Dl_info *__info,
107 void **__extra_info, int __flags) __THROW __nonnull ((2));
108
109/* These are the possible values for the FLAGS argument to `dladdr1'.
110 This indicates what extra information is stored at *EXTRA_INFO.
111 It may also be zero, in which case the EXTRA_INFO argument is not used. */
112enum
113 {
114 /* Matching symbol table entry (const ElfNN_Sym *). */
115 RTLD_DL_SYMENT = 1,
116
117 /* The object containing the address (struct link_map *). */
118 RTLD_DL_LINKMAP = 2
119 };
120
121
122/* Get information about the shared object HANDLE refers to.
123 REQUEST is from among the values below, and determines the use of ARG.
124
125 On success, returns zero. On failure, returns -1 and records an error
126 message to be fetched with `dlerror'. */
127extern int dlinfo (void *__restrict __handle,
128 int __request, void *__restrict __arg)
129 __THROW __nonnull ((1, 3));
130
131/* These are the possible values for the REQUEST argument to `dlinfo'. */
132enum
133 {
134 /* Treat ARG as `lmid_t *'; store namespace ID for HANDLE there. */
135 RTLD_DI_LMID = 1,
136
137 /* Treat ARG as `struct link_map **';
138 store the `struct link_map *' for HANDLE there. */
139 RTLD_DI_LINKMAP = 2,
140
141 RTLD_DI_CONFIGADDR = 3, /* Unsupported, defined by Solaris. */
142
143 /* Treat ARG as `Dl_serinfo *' (see below), and fill in to describe the
144 directories that will be searched for dependencies of this object.
145 RTLD_DI_SERINFOSIZE fills in just the `dls_cnt' and `dls_size'
146 entries to indicate the size of the buffer that must be passed to
147 RTLD_DI_SERINFO to fill in the full information. */
148 RTLD_DI_SERINFO = 4,
149 RTLD_DI_SERINFOSIZE = 5,
150
151 /* Treat ARG as `char *', and store there the directory name used to
152 expand $ORIGIN in this shared object's dependency file names. */
153 RTLD_DI_ORIGIN = 6,
154
155 RTLD_DI_PROFILENAME = 7, /* Unsupported, defined by Solaris. */
156 RTLD_DI_PROFILEOUT = 8, /* Unsupported, defined by Solaris. */
157
158 /* Treat ARG as `size_t *', and store there the TLS module ID
159 of this object's PT_TLS segment, as used in TLS relocations;
160 store zero if this object does not define a PT_TLS segment. */
161 RTLD_DI_TLS_MODID = 9,
162
163 /* Treat ARG as `void **', and store there a pointer to the calling
164 thread's TLS block corresponding to this object's PT_TLS segment.
165 Store a null pointer if this object does not define a PT_TLS
166 segment, or if the calling thread has not allocated a block for it. */
167 RTLD_DI_TLS_DATA = 10,
168
169 RTLD_DI_MAX = 10,
170 };
171
172
173/* This is the type of elements in `Dl_serinfo', below.
174 The `dls_name' member points to space in the buffer passed to `dlinfo'. */
175typedef struct
176{
177 char *dls_name; /* Name of library search path directory. */
178 unsigned int dls_flags; /* Indicates where this directory came from. */
179} Dl_serpath;
180
181/* This is the structure that must be passed (by reference) to `dlinfo' for
182 the RTLD_DI_SERINFO and RTLD_DI_SERINFOSIZE requests. */
183typedef struct
184{
185 size_t dls_size; /* Size in bytes of the whole buffer. */
186 unsigned int dls_cnt; /* Number of elements in `dls_serpath'. */
187 Dl_serpath dls_serpath[1]; /* Actually longer, dls_cnt elements. */
188} Dl_serinfo;
189
190#else
191
192/* Get information about the shared objects currently loaded */
193extern int dlinfo (void);
194
195#endif
196#endif /* __USE_GNU */
197
198
199__END_DECLS
200
201#endif /* dlfcn.h */