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/* ELF symbol resolve functions for VDSO objects.
Copyright (C) 2005 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include "config.h"
#include <dl-hash.h>
#include <ldsodefs.h>
void *
internal_function
_dl_vdso_vsym (const char *name, const char *version)
{
struct link_map *map = GLRO (dl_sysinfo_map);
void *value = NULL;
if (map != NULL)
{
/* Use a WEAK REF so we don't error out if the symbol is not found. */
ElfW (Sym) wsym;
memset (&wsym, 0, sizeof (ElfW (Sym)));
wsym.st_info = (unsigned char) ELFW (ST_INFO (STB_WEAK, STT_NOTYPE));
/* Compute hash value to the version string. */
struct r_found_version vers;
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;
/* Search the scope of the vdso map. */
const ElfW (Sym) *ref = &wsym;
lookup_t result = GLRO (dl_lookup_symbol_x) (name, map, &ref,
map->l_local_scope,
&vers, 0, 0, NULL);
if (ref != NULL)
value = DL_SYMBOL_ADDRESS (result, ref);
}
return value;
}
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