binutils-gdb/gas/config/obj-aout.c

/* a.out object file format
   Copyright (C) 1989, 1990, 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.

This file is part of GAS, the GNU Assembler.

GAS 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 2,
or (at your option) any later version.

GAS 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 GAS; see the file COPYING.  If not, write
to the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */

#include "as.h"
#ifdef BFD_ASSEMBLER
#undef NO_RELOC
#include "aout/aout64.h"
#endif
#include "obstack.h"

#ifndef BFD_ASSEMBLER
/* in: segT   out: N_TYPE bits */
const short seg_N_TYPE[] =
{
  N_ABS,
  N_TEXT,
  N_DATA,
  N_BSS,
  N_UNDF,			/* unknown */
  N_UNDF,			/* error */
  N_UNDF,			/* expression */
  N_UNDF,			/* debug */
  N_UNDF,			/* ntv */
  N_UNDF,			/* ptv */
  N_REGISTER,			/* register */
};

const segT N_TYPE_seg[N_TYPE + 2] =
{				/* N_TYPE == 0x1E = 32-2 */
  SEG_UNKNOWN,			/* N_UNDF == 0 */
  SEG_GOOF,
  SEG_ABSOLUTE,			/* N_ABS == 2 */
  SEG_GOOF,
  SEG_TEXT,			/* N_TEXT == 4 */
  SEG_GOOF,
  SEG_DATA,			/* N_DATA == 6 */
  SEG_GOOF,
  SEG_BSS,			/* N_BSS == 8 */
  SEG_GOOF,
  SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF,
  SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF,
  SEG_GOOF, SEG_GOOF, SEG_GOOF, SEG_GOOF,
  SEG_REGISTER,			/* dummy N_REGISTER for regs = 30 */
  SEG_GOOF,
};
#endif

static void obj_aout_line PARAMS ((int));
static void obj_aout_weak PARAMS ((int));

const pseudo_typeS obj_pseudo_table[] =
{
  {"line", obj_aout_line, 0},	/* source code line number */
  {"ln", obj_aout_line, 0},	/* coff line number that we use anyway */

  {"weak", obj_aout_weak, 0},	/* mark symbol as weak.  */

  /* coff debug pseudos (ignored) */
  {"def", s_ignore, 0},
  {"dim", s_ignore, 0},
  {"endef", s_ignore, 0},
  {"ident", s_ignore, 0},
  {"line", s_ignore, 0},
  {"ln", s_ignore, 0},
  {"scl", s_ignore, 0},
  {"size", s_ignore, 0},
  {"tag", s_ignore, 0},
  {"type", s_ignore, 0},
  {"val", s_ignore, 0},
  {"version", s_ignore, 0},

  {"optim", s_ignore, 0},	/* For sun386i cc (?) */

  /* other stuff */
  {"ABORT", s_abort, 0},

  {NULL}			/* end sentinel */
};				/* obj_pseudo_table */


#ifdef BFD_ASSEMBLER

void
obj_aout_frob_symbol (sym, punt)
     symbolS *sym;
     int *punt;
{
  flagword flags;
  asection *sec;
  int desc, type, other;

  flags = sym->bsym->flags;
  desc = S_GET_DESC (sym);
  type = S_GET_TYPE (sym);
  other = S_GET_OTHER (sym);
  sec = sym->bsym->section;

  /* Only frob simple symbols this way right now.  */
  if (! (type & ~ (N_TYPE | N_EXT)))
    {
      if (type == (N_UNDF | N_EXT)
	  && sec == &bfd_abs_section)
	sym->bsym->section = sec = bfd_und_section_ptr;

      if ((type & N_TYPE) != N_INDR
	  && (type & N_TYPE) != N_SETA
	  && (type & N_TYPE) != N_SETT
	  && (type & N_TYPE) != N_SETD
	  && (type & N_TYPE) != N_SETB
	  && type != N_WARNING
	  && (sec == &bfd_abs_section
	      || sec == &bfd_und_section))
	return;
      if (flags & BSF_EXPORT)
	type |= N_EXT;

      switch (type & N_TYPE)
	{
	case N_SETA:
	case N_SETT:
	case N_SETD:
	case N_SETB:
	  /* Set the debugging flag for constructor symbols so that
	     BFD leaves them alone.  */
	  sym->bsym->flags |= BSF_DEBUGGING;

	  /* You can't put a common symbol in a set.  The way a set
	     element works is that the symbol has a definition and a
	     name, and the linker adds the definition to the set of
	     that name.  That does not work for a common symbol,
	     because the linker can't tell which common symbol the
	     user means.  FIXME: Using as_bad here may be
	     inappropriate, since the user may want to force a
	     particular type without regard to the semantics of sets;
	     on the other hand, we certainly don't want anybody to be
	     mislead into thinking that their code will work.  */
	  if (S_IS_COMMON (sym))
	    as_bad ("Attempt to put a common symbol into set %s",
		    S_GET_NAME (sym));
	  /* Similarly, you can't put an undefined symbol in a set.  */
	  else if (! S_IS_DEFINED (sym))
	    as_bad ("Attempt to put an undefined symbol into set %s",
		    S_GET_NAME (sym));

	  break;
	case N_INDR:
	  /* Put indirect symbols in the indirect section.  */
	  sym->bsym->section = bfd_ind_section_ptr;
	  sym->bsym->flags |= BSF_INDIRECT;
	  if (type & N_EXT)
	    {
	      sym->bsym->flags |= BSF_EXPORT;
	      sym->bsym->flags &=~ BSF_LOCAL;
	    }
	  break;
	case N_WARNING:
	  /* Mark warning symbols.  */
	  sym->bsym->flags |= BSF_WARNING;
	  break;
	}
    }
  else
    {
      sym->bsym->flags |= BSF_DEBUGGING;
    }

  S_SET_TYPE (sym, type);

  /* Double check weak symbols.  */
  if (sym->bsym->flags & BSF_WEAK)
    {
      if (S_IS_COMMON (sym))
	as_bad ("Symbol `%s' can not be both weak and common",
		S_GET_NAME (sym));
    }
}

void
obj_aout_frob_file ()
{
  /* Relocation processing may require knowing the VMAs of the sections.
     Since writing to a section will cause the BFD back end to compute the
     VMAs, fake it out here....  */
  bfd_byte b = 0;
  boolean x = true;
  if (bfd_section_size (stdoutput, text_section) != 0)
    {
      x = bfd_set_section_contents (stdoutput, text_section, &b, (file_ptr) 0,
				    (bfd_size_type) 1);
    }
  else if (bfd_section_size (stdoutput, data_section) != 0)
    {
      x = bfd_set_section_contents (stdoutput, data_section, &b, (file_ptr) 0,
				    (bfd_size_type) 1);
    }
  assert (x == true);
}

#else

/* Relocation. */

/*
 *		emit_relocations()
 *
 * Crawl along a fixS chain. Emit the segment's relocations.
 */
void
obj_emit_relocations (where, fixP, segment_address_in_file)
     char **where;
     fixS *fixP;		/* Fixup chain for this segment. */
     relax_addressT segment_address_in_file;
{
  for (; fixP; fixP = fixP->fx_next)
    if (fixP->fx_done == 0)
      {
	tc_aout_fix_to_chars (*where, fixP, segment_address_in_file);
	*where += md_reloc_size;
      }
}

#ifndef obj_header_append
/* Aout file generation & utilities */
void
obj_header_append (where, headers)
     char **where;
     object_headers *headers;
{
  tc_headers_hook (headers);

#ifdef CROSS_COMPILE
  md_number_to_chars (*where, headers->header.a_info, sizeof (headers->header.a_info));
  *where += sizeof (headers->header.a_info);
  md_number_to_chars (*where, headers->header.a_text, sizeof (headers->header.a_text));
  *where += sizeof (headers->header.a_text);
  md_number_to_chars (*where, headers->header.a_data, sizeof (headers->header.a_data));
  *where += sizeof (headers->header.a_data);
  md_number_to_chars (*where, headers->header.a_bss, sizeof (headers->header.a_bss));
  *where += sizeof (headers->header.a_bss);
  md_number_to_chars (*where, headers->header.a_syms, sizeof (headers->header.a_syms));
  *where += sizeof (headers->header.a_syms);
  md_number_to_chars (*where, headers->header.a_entry, sizeof (headers->header.a_entry));
  *where += sizeof (headers->header.a_entry);
  md_number_to_chars (*where, headers->header.a_trsize, sizeof (headers->header.a_trsize));
  *where += sizeof (headers->header.a_trsize);
  md_number_to_chars (*where, headers->header.a_drsize, sizeof (headers->header.a_drsize));
  *where += sizeof (headers->header.a_drsize);

#else /* CROSS_COMPILE */

  append (where, (char *) &headers->header, sizeof (headers->header));
#endif /* CROSS_COMPILE */

}
#endif

void
obj_symbol_to_chars (where, symbolP)
     char **where;
     symbolS *symbolP;
{
  md_number_to_chars ((char *) &(S_GET_OFFSET (symbolP)), S_GET_OFFSET (symbolP), sizeof (S_GET_OFFSET (symbolP)));
  md_number_to_chars ((char *) &(S_GET_DESC (symbolP)), S_GET_DESC (symbolP), sizeof (S_GET_DESC (symbolP)));
  md_number_to_chars ((char *) &(symbolP->sy_symbol.n_value), S_GET_VALUE (symbolP), sizeof (symbolP->sy_symbol.n_value));

  append (where, (char *) &symbolP->sy_symbol, sizeof (obj_symbol_type));
}

void
obj_emit_symbols (where, symbol_rootP)
     char **where;
     symbolS *symbol_rootP;
{
  symbolS *symbolP;

  /* Emit all symbols left in the symbol chain.  */
  for (symbolP = symbol_rootP; symbolP; symbolP = symbol_next (symbolP))
    {
      /* Used to save the offset of the name. It is used to point
	 to the string in memory but must be a file offset. */
      register char *temp;

      temp = S_GET_NAME (symbolP);
      S_SET_OFFSET (symbolP, symbolP->sy_name_offset);

      /* Any symbol still undefined and is not a dbg symbol is made N_EXT. */
      if (!S_IS_DEBUG (symbolP) && !S_IS_DEFINED (symbolP))
	S_SET_EXTERNAL (symbolP);

      /* Adjust the type of a weak symbol.  */
      if (S_GET_WEAK (symbolP))
	{
	  switch (S_GET_TYPE (symbolP))
	    {
	    case N_UNDF: S_SET_TYPE (symbolP, N_WEAKU); break;
	    case N_ABS:	 S_SET_TYPE (symbolP, N_WEAKA); break;
	    case N_TEXT: S_SET_TYPE (symbolP, N_WEAKT); break;
	    case N_DATA: S_SET_TYPE (symbolP, N_WEAKD); break;
	    case N_BSS:  S_SET_TYPE (symbolP, N_WEAKB); break;
	    default: as_bad ("%s: bad type for weak symbol", temp); break;
	    }
	}

      obj_symbol_to_chars (where, symbolP);
      S_SET_NAME (symbolP, temp);
    }
}

#endif /* ! BFD_ASSEMBLER */

static void
obj_aout_line (ignore)
     int ignore;
{
  /* Assume delimiter is part of expression.
     BSD4.2 as fails with delightful bug, so we
     are not being incompatible here. */
  new_logical_line ((char *) NULL, (int) (get_absolute_expression ()));
  demand_empty_rest_of_line ();
}				/* obj_aout_line() */

/* Handle .weak.  This is a GNU extension.  */

static void
obj_aout_weak (ignore)
     int ignore;
{
  char *name;
  int c;
  symbolS *symbolP;

  do
    {
      name = input_line_pointer;
      c = get_symbol_end ();
      symbolP = symbol_find_or_make (name);
      *input_line_pointer = c;
      SKIP_WHITESPACE ();
      S_SET_WEAK (symbolP);
      if (c == ',')
	{
	  input_line_pointer++;
	  SKIP_WHITESPACE ();
	  if (*input_line_pointer == '\n')
	    c = '\n';
	}
    }
  while (c == ',');
  demand_empty_rest_of_line ();
}

void
obj_read_begin_hook ()
{
}

#ifndef BFD_ASSEMBLER

void
obj_crawl_symbol_chain (headers)
     object_headers *headers;
{
  symbolS *symbolP;
  symbolS **symbolPP;
  int symbol_number = 0;

  tc_crawl_symbol_chain (headers);

  symbolPP = &symbol_rootP;	/*->last symbol chain link. */
  while ((symbolP = *symbolPP) != NULL)
    {
      if (flag_readonly_data_in_text && (S_GET_SEGMENT (symbolP) == SEG_DATA))
	{
	  S_SET_SEGMENT (symbolP, SEG_TEXT);
	}			/* if pusing data into text */

      resolve_symbol_value (symbolP);

      /* OK, here is how we decide which symbols go out into the brave
	 new symtab.  Symbols that do are:

	 * symbols with no name (stabd's?)
	 * symbols with debug info in their N_TYPE

	 Symbols that don't are:
	 * symbols that are registers
	 * symbols with \1 as their 3rd character (numeric labels)
	 * "local labels" as defined by S_LOCAL_NAME(name) if the -L
	 switch was passed to gas.

	 All other symbols are output.  We complain if a deleted
	 symbol was marked external. */


      if (!S_IS_REGISTER (symbolP)
	  && (!S_GET_NAME (symbolP)
	      || S_IS_DEBUG (symbolP)
	      || !S_IS_DEFINED (symbolP)
	      || S_IS_EXTERNAL (symbolP)
	      || (S_GET_NAME (symbolP)[0] != '\001'
		  && (flag_keep_locals || !S_LOCAL_NAME (symbolP)))))
	{
	  symbolP->sy_number = symbol_number++;

	  /* The + 1 after strlen account for the \0 at the
			   end of each string */
	  if (!S_IS_STABD (symbolP))
	    {
	      /* Ordinary case. */
	      symbolP->sy_name_offset = string_byte_count;
	      string_byte_count += strlen (S_GET_NAME (symbolP)) + 1;
	    }
	  else			/* .Stabd case. */
	    symbolP->sy_name_offset = 0;
	  symbolPP = &(symbol_next (symbolP));
	}
      else
	{
	  if (S_IS_EXTERNAL (symbolP) || !S_IS_DEFINED (symbolP))
	    /* This warning should never get triggered any more.
	       Well, maybe if you're doing twisted things with
	       register names...  */
	    {
	      as_bad ("Local symbol %s never defined.", decode_local_label_name (S_GET_NAME (symbolP)));
	    }			/* oops. */

	  /* Unhook it from the chain */
	  *symbolPP = symbol_next (symbolP);
	}			/* if this symbol should be in the output */
    }				/* for each symbol */

  H_SET_SYMBOL_TABLE_SIZE (headers, symbol_number);
}

/*
 * Find strings by crawling along symbol table chain.
 */

void
obj_emit_strings (where)
     char **where;
{
  symbolS *symbolP;

#ifdef CROSS_COMPILE
  /* Gotta do md_ byte-ordering stuff for string_byte_count first - KWK */
  md_number_to_chars (*where, string_byte_count, sizeof (string_byte_count));
  *where += sizeof (string_byte_count);
#else /* CROSS_COMPILE */
  append (where, (char *) &string_byte_count, (unsigned long) sizeof (string_byte_count));
#endif /* CROSS_COMPILE */

  for (symbolP = symbol_rootP; symbolP; symbolP = symbol_next (symbolP))
    {
      if (S_GET_NAME (symbolP))
	append (&next_object_file_charP, S_GET_NAME (symbolP),
		(unsigned long) (strlen (S_GET_NAME (symbolP)) + 1));
    }				/* walk symbol chain */
}

#ifndef AOUT_VERSION
#define AOUT_VERSION 0
#endif

void
obj_pre_write_hook (headers)
     object_headers *headers;
{
  H_SET_DYNAMIC (headers, 0);
  H_SET_VERSION (headers, AOUT_VERSION);
  H_SET_MACHTYPE (headers, AOUT_MACHTYPE);
  tc_aout_pre_write_hook (headers);
}

void
DEFUN_VOID (s_sect)
{
  /* Strip out the section name */
  char *section_name;
  char *section_name_end;
  char c;

  unsigned int len;
  unsigned int exp;
  char *save;

  section_name = input_line_pointer;
  c = get_symbol_end ();
  section_name_end = input_line_pointer;

  len = section_name_end - section_name;
  input_line_pointer++;
  save = input_line_pointer;

  SKIP_WHITESPACE ();
  if (c == ',')
    {
      exp = get_absolute_expression ();
    }
  else if (*input_line_pointer == ',')
    {
      input_line_pointer++;
      exp = get_absolute_expression ();
    }
  else
    {
      input_line_pointer = save;
      exp = 0;
    }
  if (exp >= 1000)
    {
      as_bad ("subsegment index too high");
    }

  if (strcmp (section_name, ".text") == 0)
    {
      subseg_set (SEG_TEXT, (subsegT) exp);
    }

  if (strcmp (section_name, ".data") == 0)
    {
      if (flag_readonly_data_in_text)
	subseg_set (SEG_TEXT, (subsegT) exp + 1000);
      else
	subseg_set (SEG_DATA, (subsegT) exp);
    }

  *section_name_end = c;
}

#endif /* ! BFD_ASSEMBLER */

/* end of obj-aout.c */