Exemplo n.º 1
0
static int
enable_break2 (void)
{
  enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
  int success = 0;
  char **bkpt_namep;
  asection *interp_sect;
  struct dsbt_info *info = get_dsbt_info ();

  if (exec_bfd == NULL)
    return 0;

  if (!target_has_execution)
    return 0;

  if (info->enable_break2_done)
    return 1;

  info->interp_text_sect_low = 0;
  info->interp_text_sect_high = 0;
  info->interp_plt_sect_low = 0;
  info->interp_plt_sect_high = 0;

  /* Find the .interp section; if not found, warn the user and drop
     into the old breakpoint at symbol code.  */
  interp_sect = bfd_get_section_by_name (exec_bfd, ".interp");
  if (interp_sect)
    {
      unsigned int interp_sect_size;
      gdb_byte *buf;
      bfd *tmp_bfd = NULL;
      int status;
      CORE_ADDR addr, interp_loadmap_addr;
      gdb_byte addr_buf[TIC6X_PTR_SIZE];
      struct int_elf32_dsbt_loadmap *ldm;
      volatile struct gdb_exception ex;

      /* Read the contents of the .interp section into a local buffer;
         the contents specify the dynamic linker this program uses.  */
      interp_sect_size = bfd_section_size (exec_bfd, interp_sect);
      buf = alloca (interp_sect_size);
      bfd_get_section_contents (exec_bfd, interp_sect,
				buf, 0, interp_sect_size);

      /* Now we need to figure out where the dynamic linker was
         loaded so that we can load its symbols and place a breakpoint
         in the dynamic linker itself.  */

      TRY_CATCH (ex, RETURN_MASK_ALL)
        {
          tmp_bfd = solib_bfd_open (buf);
        }
      if (tmp_bfd == NULL)
	{
	  enable_break_failure_warning ();
	  return 0;
	}

      dsbt_get_initial_loadmaps ();
      ldm = info->interp_loadmap;

      /* Record the relocated start and end address of the dynamic linker
         text and plt section for dsbt_in_dynsym_resolve_code.  */
      interp_sect = bfd_get_section_by_name (tmp_bfd, ".text");
      if (interp_sect)
	{
	  info->interp_text_sect_low
	    = bfd_section_vma (tmp_bfd, interp_sect);
	  info->interp_text_sect_low
	    += displacement_from_map (ldm, info->interp_text_sect_low);
	  info->interp_text_sect_high
	    = info->interp_text_sect_low
	    + bfd_section_size (tmp_bfd, interp_sect);
	}
      interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt");
      if (interp_sect)
	{
	  info->interp_plt_sect_low =
	    bfd_section_vma (tmp_bfd, interp_sect);
	  info->interp_plt_sect_low
	    += displacement_from_map (ldm, info->interp_plt_sect_low);
	  info->interp_plt_sect_high =
	    info->interp_plt_sect_low + bfd_section_size (tmp_bfd, interp_sect);
	}

      addr = gdb_bfd_lookup_symbol (tmp_bfd, cmp_name, "_dl_debug_addr");
      if (addr == 0)
	{
	  warning (_("Could not find symbol _dl_debug_addr in dynamic linker"));
	  enable_break_failure_warning ();
	  bfd_close (tmp_bfd);
	  return 0;
	}

      if (solib_dsbt_debug)
	fprintf_unfiltered (gdb_stdlog,
	                    "enable_break: _dl_debug_addr (prior to relocation) = %s\n",
			    hex_string_custom (addr, 8));

      addr += displacement_from_map (ldm, addr);

      if (solib_dsbt_debug)
	fprintf_unfiltered (gdb_stdlog,
	                    "enable_break: _dl_debug_addr (after relocation) = %s\n",
			    hex_string_custom (addr, 8));

      /* Fetch the address of the r_debug struct.  */
      if (target_read_memory (addr, addr_buf, sizeof addr_buf) != 0)
	{
	  warning (_("Unable to fetch contents of _dl_debug_addr "
		     "(at address %s) from dynamic linker"),
	           hex_string_custom (addr, 8));
	}
      addr = extract_unsigned_integer (addr_buf, sizeof addr_buf, byte_order);

      if (solib_dsbt_debug)
	fprintf_unfiltered (gdb_stdlog,
	                    "enable_break: _dl_debug_addr[0..3] = %s\n",
	                    hex_string_custom (addr, 8));

      /* If it's zero, then the ldso hasn't initialized yet, and so
         there are no shared libs yet loaded.  */
      if (addr == 0)
	{
	  if (solib_dsbt_debug)
	    fprintf_unfiltered (gdb_stdlog,
	                        "enable_break: ldso not yet initialized\n");
	  /* Do not warn, but mark to run again.  */
	  return 0;
	}

      /* Fetch the r_brk field.  It's 8 bytes from the start of
         _dl_debug_addr.  */
      if (target_read_memory (addr + 8, addr_buf, sizeof addr_buf) != 0)
	{
	  warning (_("Unable to fetch _dl_debug_addr->r_brk "
		     "(at address %s) from dynamic linker"),
	           hex_string_custom (addr + 8, 8));
	  enable_break_failure_warning ();
	  bfd_close (tmp_bfd);
	  return 0;
	}
      addr = extract_unsigned_integer (addr_buf, sizeof addr_buf, byte_order);

      /* We're done with the temporary bfd.  */
      bfd_close (tmp_bfd);

      /* We're also done with the loadmap.  */
      xfree (ldm);

      /* Remove all the solib event breakpoints.  Their addresses
         may have changed since the last time we ran the program.  */
      remove_solib_event_breakpoints ();

      /* Now (finally!) create the solib breakpoint.  */
      create_solib_event_breakpoint (target_gdbarch, addr);

      info->enable_break2_done = 1;

      return 1;
    }
Exemplo n.º 2
0
static int
enable_break (void)
{
  enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
  asection *interp_sect;
  struct dsbt_info *info;

  if (exec_bfd == NULL)
    return 0;

  if (!target_has_execution)
    return 0;

  info = get_dsbt_info ();

  info->interp_text_sect_low = 0;
  info->interp_text_sect_high = 0;
  info->interp_plt_sect_low = 0;
  info->interp_plt_sect_high = 0;

  /* Find the .interp section; if not found, warn the user and drop
     into the old breakpoint at symbol code.  */
  interp_sect = bfd_get_section_by_name (exec_bfd, ".interp");
  if (interp_sect)
    {
      unsigned int interp_sect_size;
      char *buf;
      bfd *tmp_bfd = NULL;
      CORE_ADDR addr;
      gdb_byte addr_buf[TIC6X_PTR_SIZE];
      struct int_elf32_dsbt_loadmap *ldm;
      volatile struct gdb_exception ex;
      int ret;

      /* Read the contents of the .interp section into a local buffer;
	 the contents specify the dynamic linker this program uses.  */
      interp_sect_size = bfd_section_size (exec_bfd, interp_sect);
      buf = alloca (interp_sect_size);
      bfd_get_section_contents (exec_bfd, interp_sect,
				buf, 0, interp_sect_size);

      /* Now we need to figure out where the dynamic linker was
	 loaded so that we can load its symbols and place a breakpoint
	 in the dynamic linker itself.  */

      TRY_CATCH (ex, RETURN_MASK_ALL)
	{
	  tmp_bfd = solib_bfd_open (buf);
	}
      if (tmp_bfd == NULL)
	{
	  enable_break_failure_warning ();
	  return 0;
	}

      dsbt_get_initial_loadmaps ();
      ldm = info->interp_loadmap;

      /* Record the relocated start and end address of the dynamic linker
	 text and plt section for dsbt_in_dynsym_resolve_code.  */
      interp_sect = bfd_get_section_by_name (tmp_bfd, ".text");
      if (interp_sect)
	{
	  info->interp_text_sect_low
	    = bfd_section_vma (tmp_bfd, interp_sect);
	  info->interp_text_sect_low
	    += displacement_from_map (ldm, info->interp_text_sect_low);
	  info->interp_text_sect_high
	    = info->interp_text_sect_low
	    + bfd_section_size (tmp_bfd, interp_sect);
	}
      interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt");
      if (interp_sect)
	{
	  info->interp_plt_sect_low =
	    bfd_section_vma (tmp_bfd, interp_sect);
	  info->interp_plt_sect_low
	    += displacement_from_map (ldm, info->interp_plt_sect_low);
	  info->interp_plt_sect_high =
	    info->interp_plt_sect_low + bfd_section_size (tmp_bfd, interp_sect);
	}

      addr = gdb_bfd_lookup_symbol (tmp_bfd, cmp_name, "_dl_debug_state");
      if (addr != 0)
	{
	  if (solib_dsbt_debug)
	    fprintf_unfiltered (gdb_stdlog,
				"enable_break: _dl_debug_state (prior to relocation) = %s\n",
				hex_string_custom (addr, 8));
	  addr += displacement_from_map (ldm, addr);

	  if (solib_dsbt_debug)
	    fprintf_unfiltered (gdb_stdlog,
				"enable_break: _dl_debug_state (after relocation) = %s\n",
				hex_string_custom (addr, 8));

	  /* Now (finally!) create the solib breakpoint.  */
	  create_solib_event_breakpoint (target_gdbarch (), addr);

	  ret = 1;
	}
      else
	{
	  if (solib_dsbt_debug)
	    fprintf_unfiltered (gdb_stdlog,
				"enable_break: _dl_debug_state is not found\n");
	  ret = 0;
	}

      /* We're done with the temporary bfd.  */
      gdb_bfd_unref (tmp_bfd);

      /* We're also done with the loadmap.  */
      xfree (ldm);

      return ret;
    }