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/* dlsym -- Look up a symbol in a shared object loaded by `dlopen'.
Copyright (C) 1995, 1996 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <stddef.h>
#include <link.h>
#include <dlfcn.h>
#include <setjmp.h>
void *
dlsym (void *handle, const char *name)
{
ElfW(Addr) caller = (ElfW(Addr)) __builtin_return_address (0);
ElfW(Addr) loadbase;
const ElfW(Sym) *ref = NULL;
void doit (void)
{
if (handle == NULL)
/* Search the global scope. */
loadbase = _dl_lookup_symbol
(name, &ref, &(_dl_global_scope ?: _dl_default_scope)[2], NULL, 0);
else if (handle == RTLD_NEXT)
{
struct link_map *l, *match;
/* Find the highest-addressed object that CALLER is not below. */
match = NULL;
for (l = _dl_loaded; l; l = l->l_next)
if (caller >= l->l_addr && (!match || match->l_addr < l->l_addr))
match = l;
if (! match)
_dl_signal_error (0, NULL, _("\
RTLD_NEXT used in code not dynamically loaded"));
l = match;
while (l->l_loader)
l = l->l_loader;
loadbase = _dl_lookup_symbol_skip
(name, &ref, &_dl_loaded, NULL, l, 0);
}
else
{
/* Search the scope of the given object. */
struct link_map *map = handle;
struct link_map *mapscope[2] = { map, NULL };
loadbase = _dl_lookup_symbol (name, &ref, mapscope, map->l_name, 0);
}
}
return _dlerror_run (doit) ? NULL : (void *) (loadbase + ref->st_value);
}
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