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f9f2a150e8
2002-04-13 Ulrich Drepper <drepper@redhat.com> * elf/do-lookup.h [!VERSIONED]: Add new parameter flags. Use it to check whether the caller prefers getting the most recent version of a symbol of the earliest version. * elf/dl-lookup.c: Adjust all callers of do_lookup. Change _dl_do_lookup to also take the new parameter and pass it on. Change 'explicit' parameter of _dl_lookup_symbol and _dl_lookup_versioned_symbol to flags. Adjust tests. * sysdeps/generic/ldsodefs.h: Adjust prototypes. * elf/dl-libc.c: Adjust all callers of _dl_lookup_symbol and _dl_lookup_versioned_symbol. * elf/dl-reloc.c: Likewise. * elf/dl-runtime.c: Likewise. * elf/dl-sym.c: Likewise. * sysdeps/mips/dl-machine.h: Likewise.
179 lines
5.1 KiB
C
179 lines
5.1 KiB
C
/* Look up a symbol in a shared object loaded by `dlopen'.
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Copyright (C) 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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#include <stddef.h>
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#include <setjmp.h>
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#include <libintl.h>
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#include <dlfcn.h>
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#include <ldsodefs.h>
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#include <dl-hash.h>
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void *
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internal_function
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_dl_sym (void *handle, const char *name, void *who)
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{
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const ElfW(Sym) *ref = NULL;
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lookup_t result;
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ElfW(Addr) caller = (ElfW(Addr)) who;
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struct link_map *match;
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struct link_map *l;
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/* If the address is not recognized the call comes from the main
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program (we hope). */
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match = GL(dl_loaded);
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/* Find the highest-addressed object that CALLER is not below. */
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for (l = GL(dl_loaded); l != NULL; l = l->l_next)
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if (caller >= l->l_map_start && caller < l->l_map_end)
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{
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/* There must be exactly one DSO for the range of the virtual
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memory. Otherwise something is really broken. */
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match = l;
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break;
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}
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if (handle == RTLD_DEFAULT)
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/* Search the global scope as seen in the caller object. */
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result = _dl_lookup_symbol (name, match, &ref, match->l_scope, 0,
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DL_LOOKUP_RETURN_NEWEST
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| DL_LOOKUP_ADD_DEPENDENCY);
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else
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{
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if (handle != RTLD_NEXT)
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{
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/* Search the scope of the given object. */
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struct link_map *map = handle;
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result = _dl_lookup_symbol (name, match, &ref, map->l_local_scope,
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0, DL_LOOKUP_RETURN_NEWEST);
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}
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else
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{
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if (__builtin_expect (match == GL(dl_loaded), 0))
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{
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if (! GL(dl_loaded)
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|| caller < GL(dl_loaded)->l_map_start
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|| caller >= GL(dl_loaded)->l_map_end)
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_dl_signal_error (0, NULL, NULL, N_("\
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RTLD_NEXT used in code not dynamically loaded"));
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}
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l = match;
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while (l->l_loader != NULL)
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l = l->l_loader;
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result = _dl_lookup_symbol_skip (name, l, &ref, l->l_local_scope,
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match);
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}
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}
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if (ref != NULL)
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{
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#if defined USE_TLS && defined SHARED
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if (ELFW(ST_TYPE) (ref->st_info) == STT_TLS)
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/* The found symbol is a thread-local storage variable.
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Return the address for to the current thread. */
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return _dl_tls_symaddr (result, ref);
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#endif
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return DL_SYMBOL_ADDRESS (result, ref);
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}
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return NULL;
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}
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void *
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internal_function
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_dl_vsym (void *handle, const char *name, const char *version, void *who)
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{
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const ElfW(Sym) *ref = NULL;
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struct r_found_version vers;
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lookup_t result;
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ElfW(Addr) caller = (ElfW(Addr)) who;
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struct link_map *match;
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struct link_map *l;
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/* Compute hash value to the version string. */
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vers.name = version;
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vers.hidden = 1;
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vers.hash = _dl_elf_hash (version);
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/* We don't have a specific file where the symbol can be found. */
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vers.filename = NULL;
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/* If the address is not recognized the call comes from the main
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program (we hope). */
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match = GL(dl_loaded);
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/* Find the highest-addressed object that CALLER is not below. */
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for (l = GL(dl_loaded); l != NULL; l = l->l_next)
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if (caller >= l->l_map_start && caller < l->l_map_end)
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{
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/* There must be exactly one DSO for the range of the virtual
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memory. Otherwise something is really broken. */
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match = l;
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break;
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}
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if (handle == RTLD_DEFAULT)
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/* Search the global scope. */
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result = _dl_lookup_versioned_symbol (name, match, &ref, match->l_scope,
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&vers, 0, DL_LOOKUP_ADD_DEPENDENCY);
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else if (handle == RTLD_NEXT)
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{
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if (__builtin_expect (match == GL(dl_loaded), 0))
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{
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if (! GL(dl_loaded)
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|| caller < GL(dl_loaded)->l_map_start
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|| caller >= GL(dl_loaded)->l_map_end)
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_dl_signal_error (0, NULL, NULL, N_("\
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RTLD_NEXT used in code not dynamically loaded"));
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}
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l = match;
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while (l->l_loader != NULL)
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l = l->l_loader;
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result = _dl_lookup_versioned_symbol_skip (name, l, &ref,
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l->l_local_scope,
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&vers, match);
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}
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else
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{
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/* Search the scope of the given object. */
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struct link_map *map = handle;
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result = _dl_lookup_versioned_symbol (name, map, &ref,
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map->l_local_scope, &vers, 0, 0);
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}
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if (ref != NULL)
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{
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#if defined USE_TLS && defined SHARED
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if (ELFW(ST_TYPE) (ref->st_info) == STT_TLS)
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/* The found symbol is a thread-local storage variable.
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Return the address for to the current thread. */
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return _dl_tls_symaddr (result, ref);
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#endif
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return DL_SYMBOL_ADDRESS (result, ref);
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}
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return NULL;
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}
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