aoutx.h

早期freebsd实现

    r_index =  (bytes->r_index[2] << 16)
      | (bytes->r_index[1] << 8)
	|  bytes->r_index[0];
    r_extern  = (0 != (bytes->r_type[0] & RELOC_STD_BITS_EXTERN_LITTLE));
    r_pcrel   = (0 != (bytes->r_type[0] & RELOC_STD_BITS_PCREL_LITTLE));
    r_baserel = (0 != (bytes->r_type[0] & RELOC_STD_BITS_BASEREL_LITTLE));
    r_jmptable= (0 != (bytes->r_type[0] & RELOC_STD_BITS_JMPTABLE_LITTLE));
    r_relative= (0 != (bytes->r_type[0] & RELOC_STD_BITS_RELATIVE_LITTLE));
    r_length  =       (bytes->r_type[0] & RELOC_STD_BITS_LENGTH_LITTLE) 
      			>> RELOC_STD_BITS_LENGTH_SH_LITTLE;
  }

  cache_ptr->howto =  howto_table_std + r_length + 4 * r_pcrel;
  /* FIXME-soon:  Roll baserel, jmptable, relative bits into howto setting */

  MOVE_ADDRESS(0);
}

/* Reloc hackery */

boolean
DEFUN(NAME(aout,slurp_reloc_table),(abfd, asect, symbols),
      bfd *abfd AND
      sec_ptr asect AND
      asymbol **symbols)
{
  unsigned int count;
  bfd_size_type reloc_size;
  PTR relocs;
  arelent *reloc_cache;
  size_t each_size;

  if (asect->relocation) return true;

  if (asect->flags & SEC_CONSTRUCTOR) return true;

  if (asect == obj_datasec (abfd)) {
    reloc_size = exec_hdr(abfd)->a_drsize;
    goto doit;
  }

  if (asect == obj_textsec (abfd)) {
    reloc_size = exec_hdr(abfd)->a_trsize;
    goto doit;
  }

  bfd_error = invalid_operation;
  return false;

 doit:
  bfd_seek (abfd, asect->rel_filepos, SEEK_SET);
  each_size = obj_reloc_entry_size (abfd);

  count = reloc_size / each_size;


  reloc_cache = (arelent *) bfd_zalloc (abfd, (size_t)(count * sizeof
						       (arelent)));
  if (!reloc_cache) {
nomem:
    bfd_error = no_memory;
    return false;
  }

  relocs = (PTR) bfd_alloc (abfd, reloc_size);
  if (!relocs) {
    bfd_release (abfd, reloc_cache);
    goto nomem;
  }

  if (bfd_read (relocs, 1, reloc_size, abfd) != reloc_size) {
    bfd_release (abfd, relocs);
    bfd_release (abfd, reloc_cache);
    bfd_error = system_call_error;
    return false;
  }

  if (each_size == RELOC_EXT_SIZE) {
    register struct reloc_ext_external *rptr = (struct reloc_ext_external *) relocs;
    unsigned int counter = 0;
    arelent *cache_ptr = reloc_cache;

    for (; counter < count; counter++, rptr++, cache_ptr++) {
      NAME(aout,swap_ext_reloc_in)(abfd, rptr, cache_ptr, symbols);
    }
  } else {
    register struct reloc_std_external *rptr = (struct reloc_std_external*) relocs;
    unsigned int counter = 0;
    arelent *cache_ptr = reloc_cache;

    for (; counter < count; counter++, rptr++, cache_ptr++) {
	NAME(aout,swap_std_reloc_in)(abfd, rptr, cache_ptr, symbols);
    }

  }

  bfd_release (abfd,relocs);
  asect->relocation = reloc_cache;
  asect->reloc_count = count;
  return true;
}



/* Write out a relocation section into an object file.  */

boolean
DEFUN(NAME(aout,squirt_out_relocs),(abfd, section),
      bfd *abfd AND
      asection *section)
{
  arelent **generic;
  unsigned char *native, *natptr;
  size_t each_size;

  unsigned int count = section->reloc_count;
  size_t natsize;

  if (count == 0) return true;

  each_size = obj_reloc_entry_size (abfd);
  natsize = each_size * count;
  native = (unsigned char *) bfd_zalloc (abfd, natsize);
  if (!native) {
    bfd_error = no_memory;
    return false;
  }

  generic = section->orelocation;

  if (each_size == RELOC_EXT_SIZE) 
    {
      for (natptr = native;
	   count != 0;
	   --count, natptr += each_size, ++generic)
	NAME(aout,swap_ext_reloc_out) (abfd, *generic, (struct reloc_ext_external *)natptr);
    }
  else 
    {
      for (natptr = native;
	   count != 0;
	   --count, natptr += each_size, ++generic)
	NAME(aout,swap_std_reloc_out)(abfd, *generic, (struct reloc_std_external *)natptr);
    }

  if ( bfd_write ((PTR) native, 1, natsize, abfd) != natsize) {
    bfd_release(abfd, native);
    return false;
  }
  bfd_release (abfd, native);

  return true;
}

/* This is stupid.  This function should be a boolean predicate */
unsigned int
DEFUN(NAME(aout,canonicalize_reloc),(abfd, section, relptr, symbols),
      bfd *abfd AND
      sec_ptr section AND
      arelent **relptr AND
      asymbol **symbols)
{
  arelent *tblptr = section->relocation;
  unsigned int count;

  if (!(tblptr || NAME(aout,slurp_reloc_table)(abfd, section, symbols)))
    return 0;

  if (section->flags & SEC_CONSTRUCTOR) {
    arelent_chain *chain = section->constructor_chain;
    for (count = 0; count < section->reloc_count; count ++) {
      *relptr ++ = &chain->relent;
      chain = chain->next;
    }
  }
  else {
    tblptr = section->relocation;
    if (!tblptr) return 0;

    for (count = 0; count++ < section->reloc_count;) 
      {
	*relptr++ = tblptr++;
      }
  }
  *relptr = 0;

  return section->reloc_count;
}

unsigned int
DEFUN(NAME(aout,get_reloc_upper_bound),(abfd, asect),
     bfd *abfd AND
     sec_ptr asect)
{
  if (bfd_get_format (abfd) != bfd_object) {
    bfd_error = invalid_operation;
    return 0;
  }
  if (asect->flags & SEC_CONSTRUCTOR) {
    return (sizeof (arelent *) * (asect->reloc_count+1));
  }


  if (asect == obj_datasec (abfd))
    return (sizeof (arelent *) *
            ((exec_hdr(abfd)->a_drsize / obj_reloc_entry_size (abfd))
             +1));

  if (asect == obj_textsec (abfd))
    return (sizeof (arelent *) *
            ((exec_hdr(abfd)->a_trsize / obj_reloc_entry_size (abfd))
             +1));

  bfd_error = invalid_operation;
  return 0;
}


 unsigned int
DEFUN(NAME(aout,get_symtab_upper_bound),(abfd),
     bfd *abfd)
{
  if (!NAME(aout,slurp_symbol_table)(abfd)) return 0;

  return (bfd_get_symcount (abfd)+1) * (sizeof (aout_symbol_type *));
}
 alent *
DEFUN(NAME(aout,get_lineno),(ignore_abfd, ignore_symbol),
      bfd *ignore_abfd AND
      asymbol *ignore_symbol)
{
return (alent *)NULL;
}


void 
DEFUN(NAME(aout,print_symbol),(ignore_abfd, afile, symbol, how),
      bfd *ignore_abfd AND
      PTR afile AND
      asymbol *symbol AND
      bfd_print_symbol_type how)
{
  FILE *file = (FILE *)afile;

  switch (how) {
  case bfd_print_symbol_name:
    if (symbol->name)
      fprintf(file,"%s", symbol->name);
    break;
  case bfd_print_symbol_more:
    fprintf(file,"%4x %2x %2x",(unsigned)(aout_symbol(symbol)->desc & 0xffff),
	    (unsigned)(aout_symbol(symbol)->other & 0xff),
	    (unsigned)(aout_symbol(symbol)->type));
    break;
  case bfd_print_symbol_all:
    {
   CONST char *section_name = symbol->section->name;


      bfd_print_symbol_vandf((PTR)file,symbol);

      fprintf(file," %-5s %04x %02x %02x",
	      section_name,
	      (unsigned)(aout_symbol(symbol)->desc & 0xffff),
	      (unsigned)(aout_symbol(symbol)->other & 0xff),
	      (unsigned)(aout_symbol(symbol)->type  & 0xff));
      if (symbol->name)
        fprintf(file," %s", symbol->name);
    }
    break;
  case bfd_print_symbol_nm:
    {
      int section_code = bfd_decode_symclass  (symbol);

      if (section_code == 'U')
	fprintf(file, "        ");
      else
	fprintf_vma(file, symbol->value+symbol->section->vma);
      if (section_code == '?')
	{
	  int type_code = aout_symbol(symbol)->type  & 0xff;
	  char *stab_name = aout_stab_name(type_code);
	  char buf[10];
	  if (stab_name == NULL)
	    {
	      sprintf(buf, "(%d)", type_code);
	      stab_name = buf;
	    }
	  fprintf(file," - %02x %04x %5s",
		  (unsigned)(aout_symbol(symbol)->other & 0xff),
		  (unsigned)(aout_symbol(symbol)->desc & 0xffff),
		  stab_name);
        }
      else
	fprintf(file," %c", section_code);
      if (symbol->name)
        fprintf(file," %s", symbol->name);
    }
    break;
  }
}

/* 
 provided a BFD, a section and an offset into the section, calculate
 and return the name of the source file and the line nearest to the
 wanted location.
*/
 
boolean
DEFUN(NAME(aout,find_nearest_line),(abfd,
				     section,
				     symbols,
				     offset,
				     filename_ptr,
				     functionname_ptr,
				     line_ptr),
      bfd *abfd AND
      asection *section AND
      asymbol **symbols AND
      bfd_vma offset AND
      CONST char **filename_ptr AND
      CONST char **functionname_ptr AND
      unsigned int *line_ptr)
{
  /* Run down the file looking for the filename, function and linenumber */
  asymbol **p;
  static  char buffer[100];
  static  char filename_buffer[200];
  CONST char *directory_name = NULL;
  CONST char *main_file_name = NULL;
  CONST char *current_file_name = NULL;
  CONST char *line_file_name = NULL; /* Value of current_file_name at line number. */
  bfd_vma high_line_vma = ~0;
  bfd_vma low_func_vma = 0;
  asymbol *func = 0;
  *filename_ptr = abfd->filename;
  *functionname_ptr = 0;
  *line_ptr = 0;
  if (symbols != (asymbol **)NULL) {
    for (p = symbols; *p; p++) {
      aout_symbol_type  *q = (aout_symbol_type *)(*p);
    next:
      switch (q->type){
      case N_SO:
	main_file_name = current_file_name = q->symbol.name;
	/* Look ahead to next symbol to check if that too is an N_SO. */
	p++;
	if (*p == NULL)
	  break;
	q = (aout_symbol_type *)(*p);
	if (q->type != (int)N_SO)
	  goto next;

	/* Found a second N_SO  First is directory; second is filename. */
	directory_name = current_file_name;
	main_file_name = current_file_name = q->symbol.name;
	if (obj_textsec(abfd) != section)
	  goto done;
	break;
      case N_SOL:
	current_file_name = q->symbol.name;
	break;

      case N_SLINE:

      case N_DSLINE:
      case N_BSLINE:
	/* We'll keep this if it resolves nearer than the one we have already */
	if (q->symbol.value >= offset &&
	    q->symbol.value < high_line_vma) {
	  *line_ptr = q->desc;
	  high_line_vma = q->symbol.value;
	  line_file_name = current_file_name;
	}
	break;
      case N_FUN:
	{
	  /* We'll keep this if it is nearer than the one we have already */
	  if (q->symbol.value >= low_func_vma &&
	      q->symbol.value <= offset) {
	    low_func_vma = q->symbol.value;
	    func = (asymbol *)q;
	  }
	  if (*line_ptr && func) {
	    CONST char *function = func->name;
	    char *p;
	    strncpy(buffer, function, sizeof(buffer)-1);
	    buffer[sizeof(buffer)-1] = 0;
	    /* Have to remove : stuff */
	    p = strchr(buffer,':');
	    if (p != NULL) { *p = '\0'; }
	    *functionname_ptr = buffer;
	    goto done;

	  }
	}
	break;
      }
    }
  }

 done:
  if (*line_ptr)
    main_file_name = line_file_name;
  if (main_file_name) {
      if (main_file_name[0] == '/' || directory_name == NULL)
	  *filename_ptr = main_file_name;
      else {
	  sprintf(filename_buffer, "%.140s%.50s",
		  directory_name, main_file_name);
	  *filename_ptr = filename_buffer;
      }
  }
  return true;

}

int 
DEFUN(NAME(aout,sizeof_headers),(abfd, execable),
      bfd *abfd AND
      boolean execable)
{
  return adata(abfd).exec_bytes_size;
}