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glibc/elf/dynamic-link.h
Ulrich Drepper dacc8ffa42 Update. 
2000-03-30  Ulrich Drepper  <drepper@redhat.com>

	Implement dynamic determination of constructor/destructor order in
	the dynamic linker.
	* elf/Versions [ld.so] (GLIBC_2.0): Remove _dl_init_next.
	(GLIBC_2.2): Add _dl_init.
	* elf/dl-close.c: Also call all destructors in FINI_ARRAY.
	r_duplist is not anymore allocated separately.  l_initfini is and
	therefore free it if necessary.
	* elf/dl-deps.c: If a searchlist has to be allocated, put all in one
	malloc block.  Otherwise allocate l_initfini list only.
	Put dependencies for the object in l_initfini list.
	Sort dependencies for the object to be loaded topologically.
	* elf/dl-fini.c: Before running the destructors sort the topologically.
	* elf/dl-init.c (_dl_init): Renamed from _dl_init_next.  Rewrite to
	call constructors instead of iterating over the pointers.  Get list of
	objects for which to run constructors from l_initfini element. Accept
	argc, argv, and env as parameters and pass them to the constructors.
	* elf/ld-load.c (_dl_map_object_from_fd): Initialize l_ldnum member
	with size of dynamic section.
	* elf/dl-open.c (dl_open_worker): Only call _dl_init instead of
	_dl_init_next and calling constructors ourself.
	* elf/dl-preinit.c (_dl_preinit): Renamed from _dl_preinit_next.
	Take argc, argv, and env as parameters and pass them to the
	constructors.  Rewrite to call all constructors and not iterate over
	the pointers.
	* elf/dynamic-link.h: Don't relocate DT_FINI_ARRAY entry.  Don't
	precompute l_initcount and l_preinitcount.
	* elf/link.h (struct link_map): Add l_ldnum member.
	Make l_phdr_allocated part of the bitfield.  Remove l_runcount,
	l_initcount, and l_preinitcount.  Add l_initfini.
	* sysdeps/generic/ldsodefs.h: Replace _dl_init_next prototype with
	one for _dl_init.
	* sysdeps/i386/dl-machine (RTLD_START): Rewrite to match new init
	function interface.
	* sysdeps/unix/sysv/linux/init-first.h: Removed.
	* sysdeps/unix/sysv/linux/Dist: Delete file here as well.
	* sysdeps/unix/sysv/linux/init-first.c [PIC]: Don't use
	SYSDEP_CALL_INIT.  Make _init a strong alias of init.  The calling
	conventions now match.

	* sysdeps/generic/libc-start.c: Calling __libc_init_first has no
	effect for shared objects.  Don't emit message and call only for
	static library.
2000-03-30 16:30:49 +00:00

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/* Inline functions for dynamic linking.
Copyright (C) 1995,96,97,98,99,2000 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 <elf.h>
#include <dl-machine.h>
#include <assert.h>
#ifndef VERSYMIDX
# define VERSYMIDX(sym) (DT_NUM + DT_PROCNUM + DT_VERSIONTAGIDX (sym))
#endif
/* Global read-only variable defined in rtld.c which is nonzero if we
shall give more warning messages. */
extern int _dl_verbose __attribute__ ((unused));
/* Read the dynamic section at DYN and fill in INFO with indices DT_*. */
static inline void __attribute__ ((unused))
elf_get_dynamic_info (struct link_map *l)
{
ElfW(Dyn) *dyn = l->l_ld;
ElfW(Addr) l_addr;
ElfW(Dyn) **info;
if (! dyn)
return;
l_addr = l->l_addr;
info = l->l_info;
while (dyn->d_tag != DT_NULL)
{
if (dyn->d_tag < DT_NUM)
info[dyn->d_tag] = dyn;
else if (dyn->d_tag >= DT_LOPROC &&
dyn->d_tag < DT_LOPROC + DT_PROCNUM)
info[dyn->d_tag - DT_LOPROC + DT_NUM] = dyn;
else if ((Elf32_Word) DT_VERSIONTAGIDX (dyn->d_tag) < DT_VERSIONTAGNUM)
info[VERSYMIDX (dyn->d_tag)] = dyn;
else if ((Elf32_Word) DT_EXTRATAGIDX (dyn->d_tag) < DT_EXTRANUM)
info[DT_EXTRATAGIDX (dyn->d_tag) + DT_NUM + DT_PROCNUM
+ DT_VERSIONTAGNUM] = dyn;
else
assert (! "bad dynamic tag");
++dyn;
}
#ifndef DL_RO_DYN_SECTION
if (info[DT_PLTGOT] != NULL)
info[DT_PLTGOT]->d_un.d_ptr += l_addr;
if (info[DT_STRTAB] != NULL)
info[DT_STRTAB]->d_un.d_ptr += l_addr;
if (info[DT_SYMTAB] != NULL)
info[DT_SYMTAB]->d_un.d_ptr += l_addr;
# if ! ELF_MACHINE_NO_RELA
if (info[DT_RELA] != NULL)
{
assert (info[DT_RELAENT]->d_un.d_val == sizeof (ElfW(Rela)));
info[DT_RELA]->d_un.d_ptr += l_addr;
}
# endif
# if ! ELF_MACHINE_NO_REL
if (info[DT_REL] != NULL)
{
assert (info[DT_RELENT]->d_un.d_val == sizeof (ElfW(Rel)));
info[DT_REL]->d_un.d_ptr += l_addr;
}
# endif
#endif
if (info[DT_PLTREL] != NULL)
{
# if ELF_MACHINE_NO_RELA
assert (info[DT_PLTREL]->d_un.d_val == DT_REL);
# elif ELF_MACHINE_NO_REL
assert (info[DT_PLTREL]->d_un.d_val == DT_RELA);
# else
assert (info[DT_PLTREL]->d_un.d_val == DT_REL
|| info[DT_PLTREL]->d_un.d_val == DT_RELA);
# endif
}
#ifndef DL_RO_DYN_SECTION
if (info[DT_JMPREL] != NULL)
info[DT_JMPREL]->d_un.d_ptr += l_addr;
if (info[VERSYMIDX (DT_VERSYM)] != NULL)
info[VERSYMIDX (DT_VERSYM)]->d_un.d_ptr += l_addr;
#endif
if (info[DT_FLAGS] != NULL)
{
/* Flags are used. Translate to the old form where available.
Since these l_info entries are only tested for NULL pointers it
is ok if they point to the DT_FLAGS entry. */
ElfW(Word) flags = info[DT_FLAGS]->d_un.d_val;
if (flags & DF_SYMBOLIC)
info[DT_SYMBOLIC] = info[DT_FLAGS];
if (flags & DF_TEXTREL)
info[DT_TEXTREL] = info[DT_FLAGS];
if (flags & DF_BIND_NOW)
info[DT_BIND_NOW] = info[DT_FLAGS];
}
if (info[DT_RUNPATH] != NULL)
/* If both RUNPATH and RPATH are given, the latter is ignored. */
info[DT_RPATH] = NULL;
}
#ifdef RESOLVE
/* Get the definitions of `elf_dynamic_do_rel' and `elf_dynamic_do_rela'.
These functions are almost identical, so we use cpp magic to avoid
duplicating their code. It cannot be done in a more general function
because we must be able to completely inline. */
/* On some machines, notably SPARC, DT_REL* includes DT_JMPREL in its
range. Note that according to the ELF spec, this is completely legal!
But conditionally define things so that on machines we know this will
not happen we do something more optimal. */
# ifdef ELF_MACHINE_PLTREL_OVERLAP
# define _ELF_DYNAMIC_DO_RELOC(RELOC, reloc, map, do_lazy, test_rel) \
do { \
struct { ElfW(Addr) start, size; int lazy; } ranges[3]; \
int ranges_index; \
\
ranges[0].lazy = ranges[2].lazy = 0; \
ranges[1].lazy = 1; \
ranges[0].size = ranges[1].size = ranges[2].size = 0; \
\
if ((map)->l_info[DT_##RELOC]) \
{ \
ranges[0].start = D_PTR ((map), l_info[DT_##RELOC]); \
ranges[0].size = (map)->l_info[DT_##RELOC##SZ]->d_un.d_val; \
} \
\
if ((do_lazy) \
&& (map)->l_info[DT_PLTREL] \
&& (!test_rel || (map)->l_info[DT_PLTREL]->d_un.d_val == DT_##RELOC)) \
{ \
ranges[1].start = D_PTR ((map), l_info[DT_JMPREL]); \
ranges[1].size = (map)->l_info[DT_PLTRELSZ]->d_un.d_val; \
ranges[2].start = ranges[1].start + ranges[1].size; \
ranges[2].size = ranges[0].start + ranges[0].size - ranges[2].start; \
ranges[0].size = ranges[1].start - ranges[0].start; \
} \
\
for (ranges_index = 0; ranges_index < 3; ++ranges_index) \
elf_dynamic_do_##reloc ((map), \
ranges[ranges_index].start, \
ranges[ranges_index].size, \
ranges[ranges_index].lazy); \
} while (0)
# else
# define _ELF_DYNAMIC_DO_RELOC(RELOC, reloc, map, do_lazy, test_rel) \
do { \
struct { ElfW(Addr) start, size; int lazy; } ranges[2]; \
int ranges_index; \
ranges[0].lazy = 0; \
ranges[0].size = ranges[1].size = 0; \
ranges[0].start = 0; \
\
if ((map)->l_info[DT_##RELOC]) \
{ \
ranges[0].start = D_PTR ((map), l_info[DT_##RELOC]); \
ranges[0].size = (map)->l_info[DT_##RELOC##SZ]->d_un.d_val; \
} \
if ((map)->l_info[DT_PLTREL] \
&& (!test_rel || (map)->l_info[DT_PLTREL]->d_un.d_val == DT_##RELOC)) \
{ \
ElfW(Addr) start = D_PTR ((map), l_info[DT_JMPREL]); \
\
if ((do_lazy) \
/* This test does not only detect whether the relocation \
sections are in the right order, it also checks whether \
there is a DT_REL/DT_RELA section. */ \
|| ranges[0].start + ranges[0].size != start) \
{ \
ranges[1].start = start; \
ranges[1].size = (map)->l_info[DT_PLTRELSZ]->d_un.d_val; \
ranges[1].lazy = (do_lazy); \
} \
else \
/* Combine processing the sections. */ \
ranges[0].size += (map)->l_info[DT_PLTRELSZ]->d_un.d_val; \
} \
\
for (ranges_index = 0; ranges_index < 2; ++ranges_index) \
elf_dynamic_do_##reloc ((map), \
ranges[ranges_index].start, \
ranges[ranges_index].size, \
ranges[ranges_index].lazy); \
} while (0)
# endif
# if ELF_MACHINE_NO_REL || ELF_MACHINE_NO_RELA
# define _ELF_CHECK_REL 0
# else
# define _ELF_CHECK_REL 1
# endif
# if ! ELF_MACHINE_NO_REL
# include "do-rel.h"
# define ELF_DYNAMIC_DO_REL(map, lazy) \
_ELF_DYNAMIC_DO_RELOC (REL, rel, map, lazy, _ELF_CHECK_REL)
# else
# define ELF_DYNAMIC_DO_REL(map, lazy) /* Nothing to do. */
# endif
# if ! ELF_MACHINE_NO_RELA
# define DO_RELA
# include "do-rel.h"
# define ELF_DYNAMIC_DO_RELA(map, lazy) \
_ELF_DYNAMIC_DO_RELOC (RELA, rela, map, lazy, _ELF_CHECK_REL)
# else
# define ELF_DYNAMIC_DO_RELA(map, lazy) /* Nothing to do. */
# endif
/* This can't just be an inline function because GCC is too dumb
to inline functions containing inlines themselves. */
# define ELF_DYNAMIC_RELOCATE(map, lazy, consider_profile) \
do { \
int edr_lazy = elf_machine_runtime_setup ((map), (lazy), \
(consider_profile)); \
ELF_DYNAMIC_DO_REL ((map), edr_lazy); \
ELF_DYNAMIC_DO_RELA ((map), edr_lazy); \
} while (0)
#endif
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