mirror of
git://sourceware.org/git/glibc.git
synced 2024-11-21 01:12:26 +08:00
91 lines
2.4 KiB
C
91 lines
2.4 KiB
C
/* Look up a symbol in a shared object loaded by `dlopen'.
|
|
Copyright (C) 1995-2023 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 Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <dlfcn.h>
|
|
#include <ldsodefs.h>
|
|
#include <shlib-compat.h>
|
|
#include <stddef.h>
|
|
|
|
struct dlsym_args
|
|
{
|
|
/* The arguments to dlsym_doit. */
|
|
void *handle;
|
|
const char *name;
|
|
void *who;
|
|
|
|
/* The return value of dlsym_doit. */
|
|
void *sym;
|
|
};
|
|
|
|
static void
|
|
dlsym_doit (void *a)
|
|
{
|
|
struct dlsym_args *args = (struct dlsym_args *) a;
|
|
|
|
args->sym = _dl_sym (args->handle, args->name, args->who);
|
|
}
|
|
|
|
static void *
|
|
dlsym_implementation (void *handle, const char *name, void *dl_caller)
|
|
{
|
|
struct dlsym_args args;
|
|
args.who = dl_caller;
|
|
args.handle = handle;
|
|
args.name = name;
|
|
|
|
/* Protect against concurrent loads and unloads. */
|
|
__rtld_lock_lock_recursive (GL(dl_load_lock));
|
|
|
|
void *result = (_dlerror_run (dlsym_doit, &args) ? NULL : args.sym);
|
|
|
|
__rtld_lock_unlock_recursive (GL(dl_load_lock));
|
|
|
|
return result;
|
|
}
|
|
|
|
#ifdef SHARED
|
|
void *
|
|
___dlsym (void *handle, const char *name)
|
|
{
|
|
if (GLRO (dl_dlfcn_hook) != NULL)
|
|
return GLRO (dl_dlfcn_hook)->dlsym (handle, name, RETURN_ADDRESS (0));
|
|
else
|
|
return dlsym_implementation (handle, name, RETURN_ADDRESS (0));
|
|
}
|
|
versioned_symbol (libc, ___dlsym, dlsym, GLIBC_2_34);
|
|
|
|
# if OTHER_SHLIB_COMPAT (libdl, GLIBC_2_0, GLIBC_2_34)
|
|
compat_symbol (libdl, ___dlsym, dlsym, GLIBC_2_0);
|
|
# endif
|
|
|
|
#else /* !SHARED */
|
|
/* Also used with _dlfcn_hook. */
|
|
void *
|
|
__dlsym (void *handle, const char *name, void *dl_caller)
|
|
{
|
|
return dlsym_implementation (handle, name, dl_caller);
|
|
}
|
|
|
|
void *
|
|
___dlsym (void *handle, const char *name)
|
|
{
|
|
return __dlsym (handle, name, RETURN_ADDRESS (0));
|
|
}
|
|
weak_alias (___dlsym, dlsym)
|
|
#endif /* !SHARED */
|