sunos.c

基于4个mips核的noc设计

	 The address is put in the ld_symbols field.  */
      s = bfd_make_section (abfd, ".dynstr");
      if (s == NULL
	  || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
	  || ! bfd_set_section_alignment (abfd, s, 2))
	return false;

      sunos_hash_table (info)->dynamic_sections_created = true;
    }

  if ((needed && ! sunos_hash_table (info)->dynamic_sections_needed)
      || info->shared)
    {
      bfd *dynobj;

      dynobj = sunos_hash_table (info)->dynobj;

      s = bfd_get_section_by_name (dynobj, ".got");
      if (s->_raw_size == 0)
	s->_raw_size = BYTES_IN_WORD;

      sunos_hash_table (info)->dynamic_sections_needed = true;
      sunos_hash_table (info)->got_needed = true;
    }

  return true;
}

/* Add dynamic symbols during a link.  This is called by the a.out
   backend linker for each object it encounters.  */

static boolean
sunos_add_dynamic_symbols (abfd, info, symsp, sym_countp, stringsp)
     bfd *abfd;
     struct bfd_link_info *info;
     struct external_nlist **symsp;
     bfd_size_type *sym_countp;
     char **stringsp;
{
  asection *s;
  bfd *dynobj;
  struct sunos_dynamic_info *dinfo;
  unsigned long need;

  /* Make sure we have all the required sections.  */
  if (info->hash->creator == abfd->xvec)
    {
      if (! sunos_create_dynamic_sections (abfd, info,
					   (((abfd->flags & DYNAMIC) != 0
					     && ! info->relocateable)
					    ? true
					    : false)))
	return false;
    }

  /* There is nothing else to do for a normal object.  */
  if ((abfd->flags & DYNAMIC) == 0)
    return true;

  dynobj = sunos_hash_table (info)->dynobj;

  /* We do not want to include the sections in a dynamic object in the
     output file.  We hack by simply clobbering the list of sections
     in the BFD.  This could be handled more cleanly by, say, a new
     section flag; the existing SEC_NEVER_LOAD flag is not the one we
     want, because that one still implies that the section takes up
     space in the output file.  If this is the first object we have
     seen, we must preserve the dynamic sections we just created.  */
  if (abfd != dynobj)
    abfd->sections = NULL;
  else
    {
      asection *s;

      for (s = abfd->sections;
	   (s->flags & SEC_LINKER_CREATED) == 0;
	   s = s->next)
	;
      abfd->sections = s;
    }

  /* The native linker seems to just ignore dynamic objects when -r is
     used.  */
  if (info->relocateable)
    return true;

  /* There's no hope of using a dynamic object which does not exactly
     match the format of the output file.  */
  if (info->hash->creator != abfd->xvec)
    {
      bfd_set_error (bfd_error_invalid_operation);
      return false;
    }

  /* Make sure we have a .need and a .rules sections.  These are only
     needed if there really is a dynamic object in the link, so they
     are not added by sunos_create_dynamic_sections.  */
  if (bfd_get_section_by_name (dynobj, ".need") == NULL)
    {
      /* The .need section holds the list of names of shared objets
	 which must be included at runtime.  The address of this
	 section is put in the ld_need field.  */
      s = bfd_make_section (dynobj, ".need");
      if (s == NULL
	  || ! bfd_set_section_flags (dynobj, s,
				      (SEC_ALLOC
				       | SEC_LOAD
				       | SEC_HAS_CONTENTS
				       | SEC_IN_MEMORY
				       | SEC_READONLY))
	  || ! bfd_set_section_alignment (dynobj, s, 2))
	return false;
    }

  if (bfd_get_section_by_name (dynobj, ".rules") == NULL)
    {
      /* The .rules section holds the path to search for shared
	 objects.  The address of this section is put in the ld_rules
	 field.  */
      s = bfd_make_section (dynobj, ".rules");
      if (s == NULL
	  || ! bfd_set_section_flags (dynobj, s,
				      (SEC_ALLOC
				       | SEC_LOAD
				       | SEC_HAS_CONTENTS
				       | SEC_IN_MEMORY
				       | SEC_READONLY))
	  || ! bfd_set_section_alignment (dynobj, s, 2))
	return false;
    }

  /* Pick up the dynamic symbols and return them to the caller.  */
  if (! sunos_slurp_dynamic_symtab (abfd))
    return false;

  dinfo = (struct sunos_dynamic_info *) obj_aout_dynamic_info (abfd);
  *symsp = dinfo->dynsym;
  *sym_countp = dinfo->dynsym_count;
  *stringsp = dinfo->dynstr;

  /* Record information about any other objects needed by this one.  */
  need = dinfo->dyninfo.ld_need;
  while (need != 0)
    {
      bfd_byte buf[16];
      unsigned long name, flags;
      unsigned short major_vno, minor_vno;
      struct bfd_link_needed_list *needed, **pp;
      char *namebuf, *p;
      size_t alc;
      bfd_byte b;
      char *namecopy;

      if (bfd_seek (abfd, need, SEEK_SET) != 0
	  || bfd_read (buf, 1, 16, abfd) != 16)
	return false;

      /* For the format of an ld_need entry, see aout/sun4.h.  We
         should probably define structs for this manipulation.  */

      name = bfd_get_32 (abfd, buf);
      flags = bfd_get_32 (abfd, buf + 4);
      major_vno = (unsigned short)bfd_get_16 (abfd, buf + 8);
      minor_vno = (unsigned short)bfd_get_16 (abfd, buf + 10);
      need = bfd_get_32 (abfd, buf + 12);

      needed = ((struct bfd_link_needed_list *)
		bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
      if (needed == NULL)
	return false;
      needed->by = abfd;

      /* We return the name as [-l]name[.maj][.min].  */
      alc = 30;
      namebuf = (char *) bfd_malloc (alc + 1);
      if (namebuf == NULL)
	return false;
      p = namebuf;

      if ((flags & 0x80000000) != 0)
	{
	  *p++ = '-';
	  *p++ = 'l';
	}
      if (bfd_seek (abfd, name, SEEK_SET) != 0)
	{
	  free (namebuf);
	  return false;
	}

      do
	{
	  if (bfd_read (&b, 1, 1, abfd) != 1)
	    {
	      free (namebuf);
	      return false;
	    }

	  if ((size_t) (p - namebuf) >= alc)
	    {
	      char *n;

	      alc *= 2;
	      n = (char *) bfd_realloc (namebuf, alc + 1);
	      if (n == NULL)
		{
		  free (namebuf);
		  return false;
		}
	      p = n + (p - namebuf);
	      namebuf = n;
	    }

	  *p++ = b;
	}
      while (b != '\0');

      if (major_vno == 0)
	*p = '\0';
      else
	{
	  char majbuf[30];
	  char minbuf[30];

	  sprintf (majbuf, ".%d", major_vno);
	  if (minor_vno == 0)
	    minbuf[0] = '\0';
	  else
	    sprintf (minbuf, ".%d", minor_vno);

	  if ((p - namebuf) + strlen (majbuf) + strlen (minbuf) >= alc)
	    {
	      char *n;

	      alc = (p - namebuf) + strlen (majbuf) + strlen (minbuf);
	      n = (char *) bfd_realloc (namebuf, alc + 1);
	      if (n == NULL)
		{
		  free (namebuf);
		  return false;
		}
	      p = n + (p - namebuf);
	      namebuf = n;
	    }

	  strcpy (p, majbuf);
	  strcat (p, minbuf);
	}

      namecopy = bfd_alloc (abfd, strlen (namebuf) + 1);
      if (namecopy == NULL)
	{
	  free (namebuf);
	  return false;
	}
      strcpy (namecopy, namebuf);
      free (namebuf);
      needed->name = namecopy;

      needed->next = NULL;

      for (pp = &sunos_hash_table (info)->needed;
	   *pp != NULL;
	   pp = &(*pp)->next)
	;
      *pp = needed;
    }

  return true;
}

/* Function to add a single symbol to the linker hash table.  This is
   a wrapper around _bfd_generic_link_add_one_symbol which handles the
   tweaking needed for dynamic linking support.  */

static boolean
sunos_add_one_symbol (info, abfd, name, flags, section, value, string,
		      copy, collect, hashp)
     struct bfd_link_info *info;
     bfd *abfd;
     const char *name;
     flagword flags;
     asection *section;
     bfd_vma value;
     const char *string;
     boolean copy;
     boolean collect;
     struct bfd_link_hash_entry **hashp;
{
  struct sunos_link_hash_entry *h;
  int new_flag;

  if ((flags & (BSF_INDIRECT | BSF_WARNING | BSF_CONSTRUCTOR)) != 0
      || ! bfd_is_und_section (section))
    h = sunos_link_hash_lookup (sunos_hash_table (info), name, true, copy,
				false);
  else
    h = ((struct sunos_link_hash_entry *)
	 bfd_wrapped_link_hash_lookup (abfd, info, name, true, copy, false));
  if (h == NULL)
    return false;

  if (hashp != NULL)
    *hashp = (struct bfd_link_hash_entry *) h;

  /* Treat a common symbol in a dynamic object as defined in the .bss
     section of the dynamic object.  We don't want to allocate space
     for it in our process image.  */
  if ((abfd->flags & DYNAMIC) != 0
      && bfd_is_com_section (section))
    section = obj_bsssec (abfd);

  if (! bfd_is_und_section (section)
      && h->root.root.type != bfd_link_hash_new
      && h->root.root.type != bfd_link_hash_undefined
      && h->root.root.type != bfd_link_hash_defweak)
    {
      /* We are defining the symbol, and it is already defined.  This
	 is a potential multiple definition error.  */
      if ((abfd->flags & DYNAMIC) != 0)
	{
	  /* The definition we are adding is from a dynamic object.
	     We do not want this new definition to override the
	     existing definition, so we pretend it is just a
	     reference.  */
	  section = bfd_und_section_ptr;
	}
      else if (h->root.root.type == bfd_link_hash_defined
	       && h->root.root.u.def.section->owner != NULL
	       && (h->root.root.u.def.section->owner->flags & DYNAMIC) != 0)
	{
	  /* The existing definition is from a dynamic object.  We
	     want to override it with the definition we just found.
	     Clobber the existing definition.  */
	  h->root.root.type = bfd_link_hash_undefined;
	  h->root.root.u.undef.abfd = h->root.root.u.def.section->owner;
	}
      else if (h->root.root.type == bfd_link_hash_common
	       && (h->root.root.u.c.p->section->owner->flags & DYNAMIC) != 0)
	{
	  /* The existing definition is from a dynamic object.  We
	     want to override it with the definition we just found.
	     Clobber the existing definition.  We can't set it to new,
	     because it is on the undefined list.  */
	  h->root.root.type = bfd_link_hash_undefined;
	  h->root.root.u.undef.abfd = h->root.root.u.c.p->section->owner;
	}
    }

  if ((abfd->flags & DYNAMIC) != 0
      && abfd->xvec == info->hash->creator
      && (h->flags & SUNOS_CONSTRUCTOR) != 0)
    {
      /* The existing symbol is a constructor symbol, and this symbol
         is from a dynamic object.  A constructor symbol is actually a
         definition, although the type will be bfd_link_hash_undefined
         at this point.  We want to ignore the definition from the
         dynamic object.  */
      section = bfd_und_section_ptr;
    }
  else if ((flags & BSF_CONSTRUCTOR) != 0
	   && (abfd->flags & DYNAMIC) == 0
	   && h->root.root.type == bfd_link_hash_defined
	   && h->root.root.u.def.section->owner != NULL
	   && (h->root.root.u.def.section->owner->flags & DYNAMIC) != 0)
    {
      /* The existing symbol is defined by a dynamic object, and this
         is a constructor symbol.  As above, we want to force the use
         of the constructor symbol from the regular object.  */
      h->root.root.type = bfd_link_hash_new;
    }

  /* Do the usual procedure for adding a symbol.  */
  if (! _bfd_generic_link_add_one_symbol (info, abfd, name, flags, section,
					  value, string, copy, collect,
					  hashp))
    return false;

  if (abfd->xvec == info->hash->creator)
    {
      /* Set a flag in the hash table entry indicating the type of
	 reference or definition we just found.  Keep a count of the
	 number of dynamic symbols we find.  A dynamic symbol is one
	 which is referenced or defined by both a regular object and a
	 shared object.  */
      if ((abfd->flags & DYNAMIC) == 0)
	{
	  if (bfd_is_und_section (section))
	    new_flag = SUNOS_REF_REGULAR;
	  else
	    new_flag = SUNOS_DEF_REGULAR;
	}
      else
	{
	  if (bfd_is_und_section (section))
	    new_flag = SUNOS_REF_DYNAMIC;
	  else
	    new_flag = SUNOS_DEF_DYNAMIC;
	}
      h->flags |= new_flag;

      if (h->dynindx == -1
	  && (h->flags & (SUNOS_DEF_REGULAR | SUNOS_REF_REGULAR)) != 0)
	{
	  ++sunos_hash_table (info)->dynsymcount;
	  h->dynindx = -2;
	}

      if ((flags & BSF_CONSTRUCTOR) != 0
	  && (abfd->flags & DYNAMIC) == 0)
	h->flags |= SUNOS_CONSTRUCTOR;
    }

  return true;
}

/* Return the list of objects needed by BFD.  */

/*ARGSUSED*/