+++ /dev/null
-/* Machine-dependent ELF dynamic relocation inline functions.
- i386/Linux 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 "i386"
-
-#include <assert.h>
-#include <string.h>
-#include <link.h>
-#include <syscall.h>
-#include <sys/mman.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)
- {
- case EM_386:
- case EM_486:
- return 1;
- default:
- return 0;
- }
-}
-
-
-/* Return the run-time address of the _GLOBAL_OFFSET_TABLE_.
- Must be inlined in a function which uses global data. */
-static inline Elf32_Addr *
-elf_machine_got (void)
-{
- register Elf32_Addr *got asm ("%ebx");
- return got;
-}
-
-
-/* Return the run-time load address of the shared object. */
-static inline Elf32_Addr
-elf_machine_load_address (void)
-{
- Elf32_Addr addr;
- asm (" call here\n"
- "here: popl %0\n"
- " subl $here, %0"
- : "=r" (addr));
- return addr;
-}
-/* The `subl' insn above will contain an R_386_32 relocation entry
- intended to insert the run-time address of the label `here'.
- This will be the first relocation in the text of the dynamic linker;
- we skip it to avoid trying to modify read-only text in this early stage. */
-#define ELF_MACHINE_BEFORE_RTLD_RELOC(dynamic_info) \
- ++(const Elf32_Rel *) (dynamic_info)[DT_REL]->d_un.d_ptr; \
- (dynamic_info)[DT_RELSZ]->d_un.d_val -= sizeof (Elf32_Rel)
-
-/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
- MAP is the object containing the reloc. */
-
-static inline void
-elf_machine_rel (struct link_map *map,
- const Elf32_Rel *reloc,
- Elf32_Addr sym_loadaddr, const Elf32_Sym *sym)
-{
- Elf32_Addr *const reloc_addr = (void *) (map->l_addr + reloc->r_offset);
- const Elf32_Addr sym_value = sym_loadaddr + sym->st_value;
-
- switch (ELF32_R_TYPE (reloc->r_info))
- {
- case R_386_COPY:
- memcpy (reloc_addr, (void *) sym_value, sym->st_size);
- break;
- case R_386_GLOB_DAT:
- case R_386_JMP_SLOT:
- *reloc_addr = sym_value;
- break;
- case R_386_32:
- if (map->l_type == lt_interpreter)
- {
- /* Undo the relocation done here during bootstrapping. Now we will
- relocate it anew, possibly using a binding found in the user
- program or a loaded library rather than the dynamic linker's
- built-in definitions used while loading those libraries. */
- const Elf32_Sym *const dlsymtab
- = (void *) (map->l_addr + map->l_info[DT_SYMTAB]->d_un.d_ptr);
- *reloc_addr -= (map->l_addr +
- dlsymtab[ELF32_R_SYM (reloc->r_info)].st_value);
- }
- *reloc_addr += sym_value;
- break;
- case R_386_RELATIVE:
- if (map->l_type != lt_interpreter) /* Already done in dynamic linker. */
- *reloc_addr += map->l_addr;
- break;
- case R_386_PC32:
- *reloc_addr = sym_value - (Elf32_Addr) reloc_addr;
- break;
- default:
- assert (! "unexpected dynamic reloc type");
- break;
- }
-}
-
-static inline void
-elf_machine_lazy_rel (struct link_map *map, const Elf32_Rel *reloc)
-{
- Elf32_Addr *const reloc_addr = (void *) (map->l_addr + reloc->r_offset);
- switch (ELF32_R_TYPE (reloc->r_info))
- {
- case R_386_JMP_SLOT:
- *reloc_addr += map->l_addr;
- break;
- default:
- assert (! "unexpected PLT reloc type");
- break;
- }
-}
-
-/* The i386 never uses Elf32_Rela relocations. */
-#define ELF_MACHINE_NO_RELA 1
-
-
-/* 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)
-{
- Elf32_Addr *got;
- 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]. */
- got = (Elf32_Addr *) (l->l_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;
-}
-
-
-/* Mask identifying addresses reserved for the user program,
- where the dynamic linker should not map anything. */
-#define ELF_MACHINE_USER_ADDRESS_MASK 0xf8000000UL
-
-
-
-/* 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 asm ("\
-.text\n\
-.globl _start\n\
-.globl _dl_start_user\n\
-_start:\n\
- call _dl_start\n\
-_dl_start_user:\n\
- # Save the user entry point address in %edi.\n\
- movl %eax, %edi\n\
- # Point %ebx at the GOT.
- call 0f\n\
-0: popl %ebx\n\
- addl $_GLOBAL_OFFSET_TABLE_+[.-0b], %ebx\n\
- # See if we were run as a command with the executable file\n\
- # name as an extra leading argument.\n\
- movl rtld_command@GOT(%ebx), %eax\n\
- movl (%eax),%eax\n\
- testl %eax,%eax\n\
- jz 0f\n\
- # Pop the original argument count, decrement it, and replace\n\
- # the original first argument pointer with the new count.\n\
- popl %eax\n\
- decl %eax\n\
- movl %eax,(%esp)\n\
- # Call _dl_init_next to return the address of an initializer\n\
- # function to run.\n\
-0: call _dl_init_next@PLT\n\
- # Check for zero return, when out of initializers.\n\
- testl %eax,%eax\n\
- jz 1f\n\
- # Call the shared object initializer function.\n\
- # NOTE: We depend only on the registers (%ebx and %edi)\n\
- # and the return address pushed by this call;\n\
- # the initializer is called with the stack just\n\
- # as it appears on entry, and it is free to move\n\
- # the stack around, as long as it winds up jumping to\n\
- # the return address on the top of the stack.\n\
- call *%eax\n\
- # Loop to call _dl_init_next for the next initializer.\n\
- jmp 0b\n\
-1: # Pass our finalizer function to the user in %edx, as per ELF ABI.\n\
- movl _dl_fini@GOT(%ebx), %edx\n\
- # Jump to the user's entry point.\n\
- jmp *%edi\n\
-");
projects / platform / upstream / glibc.git / commitdiff