1 /* Look up a symbol in a shared object loaded by `dlopen'.
2 Copyright (C) 1995, 1996, 1997, 1998 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
23 #include <elf/ldsodefs.h>
27 /* The arguments to dlsym_doit. */
30 struct r_found_version version
;
32 /* The return values of dlsym_doit. */
41 struct dlsym_args
*args
= (struct dlsym_args
*) a
;
44 if (args
->handle
== RTLD_DEFAULT
)
45 /* Search the global scope. */
46 args
->loadbase
= _dl_lookup_symbol (args
->name
, &args
->ref
,
47 _dl_global_scope
, NULL
, 0);
48 else if (args
->handle
== RTLD_NEXT
)
50 struct link_map
*l
, *match
;
52 /* Find the highest-addressed object that CALLER is not below. */
54 for (l
= _dl_loaded
; l
; l
= l
->l_next
)
55 if (args
->caller
>= l
->l_addr
&& (!match
|| match
->l_addr
< l
->l_addr
))
59 _dl_signal_error (0, NULL
, _("\
60 RTLD_NEXT used in code not dynamically loaded"));
66 args
->loadbase
= _dl_lookup_symbol_skip (args
->name
, &args
->ref
,
67 l
->l_local_scope
, NULL
, match
);
71 /* Search the scope of the given object. */
72 struct link_map
*map
= args
->handle
;
73 args
->loadbase
= _dl_lookup_symbol (args
->name
, &args
->ref
,
74 map
->l_local_scope
, map
->l_name
, 0);
80 dlsym (void *handle
, const char *name
)
82 struct dlsym_args args
;
83 args
.caller
= (ElfW(Addr
)) __builtin_return_address (0);
87 return (_dlerror_run (dlsym_doit
, &args
)
88 ? NULL
: (void *) (args
.loadbase
+ args
.ref
->st_value
));