diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/dl-vdso.c')
-rw-r--r-- | sysdeps/unix/sysv/linux/dl-vdso.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/dl-vdso.c b/sysdeps/unix/sysv/linux/dl-vdso.c new file mode 100644 index 0000000000..e1be097734 --- /dev/null +++ b/sysdeps/unix/sysv/linux/dl-vdso.c @@ -0,0 +1,59 @@ +/* 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; +} |