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/* Do relocations for ELF dynamic linking.
Copyright (C) 1995,96,97,98,99,2000,2001 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. */
/* This file may be included twice, to define both
`elf_dynamic_do_rel' and `elf_dynamic_do_rela'. */
#ifdef DO_RELA
# define elf_dynamic_do_rel elf_dynamic_do_rela
# define RELCOUNT_IDX VERSYMIDX (DT_RELACOUNT)
# define Rel Rela
# define elf_machine_rel elf_machine_rela
# define elf_machine_rel_relative elf_machine_rela_relative
#else
# define RELCOUNT_IDX VERSYMIDX (DT_RELCOUNT)
#endif
#ifndef VERSYMIDX
# define VERSYMIDX(sym) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (sym))
#endif
#ifndef VALIDX
# define VALIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
+ DT_EXTRANUM + DT_VALTAGIDX (tag))
#endif
/* Perform the relocations in MAP on the running program image as specified
by RELTAG, SZTAG. If LAZY is nonzero, this is the first pass on PLT
relocations; they should be set up to call _dl_runtime_resolve, rather
than fully resolved now. */
static inline void
elf_dynamic_do_rel (struct link_map *map,
ElfW(Addr) reladdr, ElfW(Addr) relsize,
int lazy)
{
const ElfW(Rel) *r = (const void *) reladdr;
const ElfW(Rel) *end = (const void *) (reladdr + relsize);
ElfW(Addr) l_addr = map->l_addr;
#if (!defined DO_RELA || !defined ELF_MACHINE_PLT_REL) && !defined RTLD_BOOTSTRAP
/* We never bind lazily during ld.so bootstrap. Unfortunately gcc is
not clever enough to see through all the function calls to realize
that. */
if (lazy)
{
/* Doing lazy PLT relocations; they need very little info. */
for (; r < end; ++r)
elf_machine_lazy_rel (map, l_addr, r);
}
else
#endif
{
const ElfW(Sym) *const symtab =
(const void *) D_PTR (map, l_info[DT_SYMTAB]);
ElfW(Word) nrelative = (map->l_info[RELCOUNT_IDX] == NULL
? 0 : map->l_info[RELCOUNT_IDX]->d_un.d_val);
const ElfW(Rel) *relative = r;
r = MIN (r + nrelative, end);
#ifndef RTLD_BOOTSTRAP
/* This is defined in rtld.c, but nowhere in the static libc.a; make
the reference weak so static programs can still link. This
declaration cannot be done when compiling rtld.c (i.e. #ifdef
RTLD_BOOTSTRAP) because rtld.c contains the common defn for
_dl_rtld_map, which is incompatible with a weak decl in the same
file. */
weak_extern (_dl_rtld_map);
if (map != &_dl_rtld_map) /* Already done in rtld itself. */
# ifndef DO_RELA
/* Rela platforms get the offset from r_addend and this must
be copied in the relocation address. Therefore we can skip
the relative relocations only if this is for rel
relocations... */
if (l_addr != 0)
# else
/* ...or we know the object has been prelinked. */
if (l_addr != 0 || ! map->l_info[VALIDX(DT_GNU_PRELINKED)])
# endif
#endif
for (; relative < r; ++relative)
elf_machine_rel_relative (l_addr, relative,
(void *) (l_addr + relative->r_offset));
if (map->l_info[VERSYMIDX (DT_VERSYM)])
{
const ElfW(Half) *const version =
(const void *) D_PTR (map, l_info[VERSYMIDX (DT_VERSYM)]);
for (; r < end; ++r)
{
ElfW(Half) ndx = version[ELFW(R_SYM) (r->r_info)];
elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)],
&map->l_versions[ndx],
(void *) (l_addr + r->r_offset));
}
}
else
for (; r < end; ++r)
elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)], NULL,
(void *) (l_addr + r->r_offset));
}
}
#undef elf_dynamic_do_rel
#undef Rel
#undef elf_machine_rel
#undef elf_machine_rel_relative
#undef RELCOUNT_IDX
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