glibc/sysdeps/stub/dl-machine.h

116 lines
3.6 KiB
C

/* Machine-dependent ELF dynamic relocation inline functions. Stub version.
Copyright (C) 1995 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., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#define ELF_MACHINE_NAME "stub"
#include <assert.h>
#include <string.h>
#include <link.h>
/* Return nonzero iff E_MACHINE is compatible with the running host. */
static inline int
elf_machine_matches_host (Elf32_Half e_machine)
{
switch (e_machine)
{
default:
return 0;
}
}
/* Return the run-time address of the _GLOBAL_OFFSET_TABLE_. */
static inline Elf32_Addr *
elf_machine_got (void)
{
#error "GOT not got"
}
/* Return the run-time load address of the shared object. */
static inline Elf32_Addr
elf_machine_load_address (void)
{
#error "Where am I?"
}
/* This can modify DYNAMIC_INFO to avoid relocating code in
the functions above if they are doing bizarre magic. */
#define ELF_MACHINE_BEFORE_RTLD_RELOC(dynamic_info) /* nothing */
/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
LOADADDR is the load address of the object; INFO is an array indexed
by DT_* of the .dynamic section info. */
static inline void
elf_machine_rel (Elf32_Addr loadaddr, Elf32_Dyn *info[DT_NUM],
const Elf32_Rel *reloc,
Elf32_Addr sym_loadaddr, const Elf32_Sym *sym)
{
Elf32_Addr *const reloc_addr = (Elf32_Addr *) reloc->r_offset;
const Elf32_Addr sym_value = sym_loadaddr + sym->st_value;
switch (ELF32_R_TYPE (reloc->r_info))
{
case R_MACHINE_COPY:
memcpy (reloc_addr, (void *) sym_value, sym->st_size);
break;
default:
assert (! "unexpected dynamic reloc type");
break;
}
}
static inline void
elf_machine_rela (Elf32_Addr loadaddr, Elf32_Dyn *info[DT_NUM],
const Elf32_Rela *reloc,
Elf32_Addr sym_loadaddr, const Elf32_Sym *sym)
{
_dl_signal_error (0, "Elf32_Rela relocation requested -- unused on "
ELF_MACHINE_NAME);
}
/* Set up the loaded object described by L so its unrelocated PLT
entries will jump to the on-demand fixup code in dl-runtime.c. */
static inline void
elf_machine_runtime_setup (struct link_map *l)
{
extern void _dl_runtime_resolve (Elf32_Word);
/* The GOT entries for functions in the PLT have not yet been filled
in. Their initial contents will arrange when called to push an
offset into the .rel.plt section, push _GLOBAL_OFFSET_TABLE_[1],
and then jump to _GLOBAL_OFFSET_TABLE[2]. */
Elf32_Addr *got = (Elf32_Addr *) l->l_info[DT_PLTGOT]->d_un.d_ptr;
got[1] = (Elf32_Addr) l; /* Identify this shared object. */
/* This function will get called to fix up the GOT entry indicated by
the offset on the stack, and then jump to the resolved address. */
got[2] = (Elf32_Addr) &_dl_runtime_resolve;
}
/* Initial entry point code for the dynamic linker.
The C function `_dl_start' is the real entry point;
its return value is the user program's entry point. */
#define RTLD_START #error need some startup code