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-rw-r--r--elf/dl-sym.c129
1 files changed, 129 insertions, 0 deletions
diff --git a/elf/dl-sym.c b/elf/dl-sym.c
new file mode 100644
index 0000000..441b54f
--- /dev/null
+++ b/elf/dl-sym.c
@@ -0,0 +1,129 @@
+/* Look up a symbol in a shared object loaded by `dlopen'.
+ Copyright (C) 1999 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 <setjmp.h>
+#include <libintl.h>
+
+#include <dlfcn.h>
+#include <ldsodefs.h>
+#include <dl-hash.h>
+
+void *
+internal_function
+_dl_sym (void *handle, const char *name, void *who)
+{
+ ElfW(Addr) loadbase;
+ const ElfW(Sym) *ref = NULL;
+
+ if (handle == RTLD_DEFAULT)
+ /* Search the global scope. */
+ loadbase = _dl_lookup_symbol (name, &ref, _dl_global_scope, NULL, 0);
+ else if (handle == RTLD_NEXT)
+ {
+ struct link_map *l, *match;
+ ElfW(Addr) caller = (ElfW(Addr)) who;
+
+ /* 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, l->l_local_scope,
+ NULL, match);
+ }
+ else
+ {
+ /* Search the scope of the given object. */
+ struct link_map *map = handle;
+ loadbase = _dl_lookup_symbol (name, &ref, map->l_local_scope,
+ map->l_name, 0);
+ }
+
+ if (loadbase)
+ return (void *) (loadbase + ref->st_value);
+
+ return NULL;
+}
+
+void *
+internal_function
+_dl_vsym (void *handle, const char *name, const char *version, void *who)
+{
+ ElfW(Addr) loadbase;
+ const ElfW(Sym) *ref = NULL;
+ struct r_found_version vers;
+
+ /* Compute hash value to the version string. */
+ vers.name = version;
+ vers.hidden = 1;
+ vers.hash = _dl_elf_hash (version);
+ /* We don't have a specific file where the symbol can be found. */
+ vers.filename = NULL;
+
+ if (handle == RTLD_DEFAULT)
+ /* Search the global scope. */
+ loadbase = _dl_lookup_versioned_symbol (name, &ref, _dl_global_scope,
+ NULL, &vers, 0);
+ else if (handle == RTLD_NEXT)
+ {
+ struct link_map *l, *match;
+ ElfW(Addr) caller = (ElfW(Addr)) who;
+
+ /* 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_versioned_symbol_skip (name, &ref,
+ l->l_local_scope,
+ NULL, &vers, match);
+ }
+ else
+ {
+ /* Search the scope of the given object. */
+ struct link_map *map = handle;
+ loadbase = _dl_lookup_versioned_symbol (name, &ref,
+ map->l_local_scope,
+ map->l_name, &vers, 0);
+ }
+
+ if (loadbase)
+ return (void *) (loadbase + ref->st_value);
+
+ return NULL;
+}