1 /* Handle loading and unloading shared objects for internal libc purposes.
2 Copyright (C) 1999 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Zack Weinberg <zack@rabi.columbia.edu>, 1999.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Library General Public License as
8 published by the Free Software Foundation; either version 2 of the
9 License, or (at your option) any later version.
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 Library General Public License for more details.
16 You should have received a copy of the GNU Library General Public
17 License along with the GNU C Library; see the file COPYING.LIB. If not,
18 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
25 /* The purpose of this file is to provide wrappers around the dynamic
26 linker error mechanism (similar to dlopen() et al in libdl) which
27 are usable from within libc. Generally we want to throw away the
28 string that dlerror() would return and just pass back a null pointer
29 for errors. This also lets the rest of libc not know about the error
32 Much of this code came from gconv_dl.c with slight modifications. */
36 dlerror_run (void (*operate) (void *), void *args)
38 char *last_errstring = NULL;
41 (void) _dl_catch_error (&last_errstring, operate, args);
43 result = last_errstring != NULL;
45 free (last_errstring);
50 /* These functions are called by dlerror_run... */
54 /* Argument to do_dlopen. */
57 /* Return from do_dlopen. */
63 /* Arguments to do_dlsym. */
67 /* Return values of do_dlsym. */
75 struct do_dlopen_args *args = (struct do_dlopen_args *) ptr;
76 /* Open and relocate the shared object. */
77 args->map = _dl_open (args->name, RTLD_LAZY, NULL);
83 struct do_dlsym_args *args = (struct do_dlsym_args *) ptr;
85 args->loadbase = _dl_lookup_symbol (args->name, args->map, &args->ref,
86 args->map->l_local_scope, 0);
90 do_dlclose (void *ptr)
92 _dl_close ((struct link_map *) ptr);
95 /* ... and these functions call dlerror_run. */
98 __libc_dlopen (const char *__name)
100 struct do_dlopen_args args;
103 return (dlerror_run (do_dlopen, &args) ? NULL : (void *) args.map);
107 __libc_dlsym (void *__map, const char *__name)
109 struct do_dlsym_args args;
113 return (dlerror_run (do_dlsym, &args) ? NULL
114 : (void *) (DL_SYMBOL_ADDRESS (args.loadbase, args.ref)));
118 __libc_dlclose (void *__map)
120 return dlerror_run (do_dlclose, __map);