Subversion Repositories openrisc_2011-10-31

/* ARM Symbian OS target support.

   Copyright (C) 2008, 2009, 2010

   Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"

#include "frame.h"

#include "objfiles.h"

#include "osabi.h"

#include "solib.h"

#include "solib-target.h"

#include "target.h"

#include "elf-bfd.h"

/* If PC is in a DLL import stub, return the address of the `real'

   function belonging to the stub.  */

CORE_ADDR

arm_symbian_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)

{

  struct gdbarch *gdbarch;

  enum bfd_endian byte_order;

  ULONGEST insn;

  CORE_ADDR dest;

  gdb_byte buf[4];

  if (!in_plt_section (pc, NULL))

    return 0;

  if (target_read_memory (pc, buf, 4) != 0)

    return 0;

  gdbarch = get_frame_arch (frame);

  byte_order = gdbarch_byte_order (gdbarch);

  /* ldr pc, [pc, #-4].  */

  insn = extract_unsigned_integer (buf, 4, byte_order);

  if (insn != 0xe51ff004)

    return 0;

  if (target_read_memory (pc + 4, buf, 4) != 0)

    return 0;

  dest = extract_unsigned_integer (buf, 4, byte_order);

  return gdbarch_addr_bits_remove (gdbarch, dest);

}

static void

arm_symbian_init_abi (struct gdbarch_info info,

                      struct gdbarch *gdbarch)

{

  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  /* Shared library handling.  */

  set_gdbarch_skip_trampoline_code (gdbarch, arm_symbian_skip_trampoline_code);

  /* On this target, the toolchain outputs ELF files, with `sym' for

     filename extension (e.g., `FOO.sym'); these are post-linker

     processed into PE-ish DLLs (e.g., `FOO.dll'), and it's these that

     are actually copied to and run on the target.  Naturally, when

     listing shared libraries, Symbian stubs report the DLL filenames.

     Setting this makes it so that GDB automatically looks for the

     corresponding ELF files on the host's filesystem.  */

  set_gdbarch_solib_symbols_extension (gdbarch, "sym");

  /* Canonical paths on this target look like `c:\sys\bin\bar.dll',

     for example.  */

  set_gdbarch_has_dos_based_file_system (gdbarch, 1);

  set_solib_ops (gdbarch, &solib_target_so_ops);

}

/* Recognize Symbian object files.  */

static enum gdb_osabi

arm_symbian_osabi_sniffer (bfd *abfd)

{

  Elf_Internal_Phdr *phdrs, **segments;

  long phdrs_size;

  int num_phdrs, i;

  /* Symbian executables are always shared objects (ET_DYN).  */

  if (elf_elfheader (abfd)->e_type == ET_EXEC)

    return GDB_OSABI_UNKNOWN;

  if (elf_elfheader (abfd)->e_ident[EI_OSABI] != ELFOSABI_NONE)

    return GDB_OSABI_UNKNOWN;

  /* Check for the ELF headers not being part of any PT_LOAD segment.

     Symbian is the only GDB supported (or GNU binutils supported) ARM

     target which uses a postlinker to flatten ELF files, dropping the

     ELF dynamic info in the process.  */

  phdrs_size = bfd_get_elf_phdr_upper_bound (abfd);

  if (phdrs_size == -1)

    return GDB_OSABI_UNKNOWN;

  phdrs = alloca (phdrs_size);

  num_phdrs = bfd_get_elf_phdrs (abfd, phdrs);

  if (num_phdrs == -1)

    return GDB_OSABI_UNKNOWN;

  for (i = 0; i < num_phdrs; i++)

    if (phdrs[i].p_type == PT_LOAD && phdrs[i].p_offset == 0)

      return GDB_OSABI_UNKNOWN;

  /* Looks like a Symbian binary.  */

  return GDB_OSABI_SYMBIAN;

}

void

_initialize_arm_symbian_tdep (void)

{

  gdbarch_register_osabi_sniffer (bfd_arch_arm,

                                  bfd_target_elf_flavour,

                                  arm_symbian_osabi_sniffer);

  gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_SYMBIAN,

                          arm_symbian_init_abi);

}