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/* Machine-dependent ELF dynamic relocation inline functions. Stub version.
Copyright (C) 1995-2019 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, see
<https://www.gnu.org/licenses/>. */
#define ELF_MACHINE_NAME "stub"
#include <string.h>
#include <link.h>
/* Return nonzero iff ELF header is compatible with the running host. */
static inline int
elf_machine_matches_host (const Elf32_Ehdr *ehdr)
{
switch (ehdr->e_machine)
{
default:
return 0;
}
}
/* Return the link-time address of _DYNAMIC. */
static inline Elf32_Addr
elf_machine_dynamic (void)
{
#error "Damn, no _DYNAMIC"
}
/* Return the run-time load address of the shared object. */
static inline Elf32_Addr
elf_machine_load_address (void)
{
#error "Where am I?"
}
/* Fixup a PLT entry to bounce directly to the function at VALUE. */
static inline ElfW(Addr)
elf_machine_fixup_plt (struct link_map *map, lookup_t t,
const ElfW(Sym) *refsym, const ElfW(Sym) *sym,
const ElfW(Rel) *reloc,
ElfW(Addr) *reloc_addr, ElfW(Addr) value)
{
return *reloc_addr = value;
}
/* 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. */
auto inline void
__attribute__ ((always_inline))
elf_machine_rel (Elf32_Addr loadaddr, Elf32_Dyn *info[DT_NUM],
const Elf32_Rel *reloc, const Elf32_Sym *sym,
Elf32_Addr (*resolve) (const Elf32_Sym **ref,
Elf32_Addr reloc_addr,
int noplt))
{
Elf32_Addr *const reloc_addr = (Elf32_Addr *) reloc->r_offset;
Elf32_Addr loadbase;
switch (ELF32_R_TYPE (reloc->r_info))
{
case R_MACHINE_COPY:
loadbase = (*resolve) (&sym, (Elf32_Addr) reloc_addr, 0);
memcpy (reloc_addr, (void *) (loadbase + sym->st_value), sym->st_size);
break;
default:
_dl_reloc_bad_type (map, ELF32_R_TYPE (reloc->r_info), 0);
break;
}
}
auto inline Elf32_Addr
__attribute__ ((always_inline))
elf_machine_rela (Elf32_Addr loadaddr, Elf32_Dyn *info[DT_NUM],
const Elf32_Rel *reloc, const Elf32_Sym *sym,
Elf32_Addr (*resolve) (const Elf32_Sym **ref,
Elf32_Addr reloc_addr,
int noplt))
{
_dl_signal_error (0, "Elf32_Rela relocation requested -- unused on "
NULL, 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 int
elf_machine_runtime_setup (struct link_map *l, int lazy)
{
extern void _dl_runtime_resolve (Elf32_Word);
if (lazy)
{
/* 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 *) D_PTR (l, l_info[DT_PLTGOT]);
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;
}
return lazy;
}
/* 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
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