obj-coff.c

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/* coff object file format
   Copyright 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   1999, 2000, 2001
   Free Software Foundation, Inc.

   This file is part of GAS.

   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, 59 Temple Place - Suite 330, Boston, MA
   02111-1307, USA.  */

#define OBJ_HEADER "obj-coff.h"

#include "as.h"
#include "obstack.h"
#include "subsegs.h"

/* I think this is probably always correct.  */
#ifndef KEEP_RELOC_INFO
#define KEEP_RELOC_INFO
#endif

/* The BFD_ASSEMBLER version of obj_coff_section will use this macro to set
   a new section's attributes when a directive has no valid flags or the
   "w" flag is used. This default should be appropriate for most.  */
#ifndef TC_COFF_SECTION_DEFAULT_ATTRIBUTES
#define TC_COFF_SECTION_DEFAULT_ATTRIBUTES (SEC_LOAD | SEC_DATA)
#endif

static void obj_coff_bss PARAMS ((int));
const char *s_get_name PARAMS ((symbolS * s));
static void obj_coff_ln PARAMS ((int));
static void obj_coff_def PARAMS ((int));
static void obj_coff_endef PARAMS ((int));
static void obj_coff_dim PARAMS ((int));
static void obj_coff_line PARAMS ((int));
static void obj_coff_size PARAMS ((int));
static void obj_coff_scl PARAMS ((int));
static void obj_coff_tag PARAMS ((int));
static void obj_coff_val PARAMS ((int));
static void obj_coff_type PARAMS ((int));
static void obj_coff_ident PARAMS ((int));
#ifdef BFD_ASSEMBLER
static void obj_coff_loc PARAMS((int));
#endif

/* This is used to hold the symbol built by a sequence of pseudo-ops
   from .def and .endef.  */
static symbolS *def_symbol_in_progress;

/* stack stuff */
typedef struct
  {
    unsigned long chunk_size;
    unsigned long element_size;
    unsigned long size;
    char *data;
    unsigned long pointer;
  }
stack;

static stack *
stack_init (chunk_size, element_size)
     unsigned long chunk_size;
     unsigned long element_size;
{
  stack *st;

  st = (stack *) malloc (sizeof (stack));
  if (!st)
    return 0;
  st->data = malloc (chunk_size);
  if (!st->data)
    {
      free (st);
      return 0;
    }
  st->pointer = 0;
  st->size = chunk_size;
  st->chunk_size = chunk_size;
  st->element_size = element_size;
  return st;
}

#if 0
/* Not currently used.  */
static void
stack_delete (st)
     stack *st;
{
  free (st->data);
  free (st);
}
#endif

static char *
stack_push (st, element)
     stack *st;
     char *element;
{
  if (st->pointer + st->element_size >= st->size)
    {
      st->size += st->chunk_size;
      if ((st->data = xrealloc (st->data, st->size)) == (char *) 0)
	return (char *) 0;
    }
  memcpy (st->data + st->pointer, element, st->element_size);
  st->pointer += st->element_size;
  return st->data + st->pointer;
}

static char *
stack_pop (st)
     stack *st;
{
  if (st->pointer < st->element_size)
    {
      st->pointer = 0;
      return (char *) 0;
    }
  st->pointer -= st->element_size;
  return st->data + st->pointer;
}

/*
 * Maintain a list of the tagnames of the structres.
 */

static struct hash_control *tag_hash;

static void
tag_init ()
{
  tag_hash = hash_new ();
}

static void
tag_insert (name, symbolP)
     const char *name;
     symbolS *symbolP;
{
  const char *error_string;

  if ((error_string = hash_jam (tag_hash, name, (char *) symbolP)))
    {
      as_fatal (_("Inserting \"%s\" into structure table failed: %s"),
		name, error_string);
    }
}

static symbolS *
tag_find (name)
     char *name;
{
#ifdef STRIP_UNDERSCORE
  if (*name == '_')
    name++;
#endif /* STRIP_UNDERSCORE */
  return (symbolS *) hash_find (tag_hash, name);
}

static symbolS *
tag_find_or_make (name)
     char *name;
{
  symbolS *symbolP;

  if ((symbolP = tag_find (name)) == NULL)
    {
      symbolP = symbol_new (name, undefined_section,
			    0, &zero_address_frag);

      tag_insert (S_GET_NAME (symbolP), symbolP);
#ifdef BFD_ASSEMBLER
      symbol_table_insert (symbolP);
#endif
    }				/* not found */

  return symbolP;
}

/* We accept the .bss directive to set the section for backward
   compatibility with earlier versions of gas.  */

static void
obj_coff_bss (ignore)
     int ignore ATTRIBUTE_UNUSED;
{
  if (*input_line_pointer == '\n')
    subseg_new (".bss", get_absolute_expression ());
  else
    s_lcomm (0);
}

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

static void
obj_coff_weak (ignore)
     int ignore ATTRIBUTE_UNUSED;
{
  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 ();

#if defined BFD_ASSEMBLER || defined S_SET_WEAK
      S_SET_WEAK (symbolP);
#endif

#ifdef TE_PE
      S_SET_STORAGE_CLASS (symbolP, C_NT_WEAK);
#else
      S_SET_STORAGE_CLASS (symbolP, C_WEAKEXT);
#endif

      if (c == ',')
	{
	  input_line_pointer++;
	  SKIP_WHITESPACE ();
	  if (*input_line_pointer == '\n')
	    c = '\n';
	}
    }
  while (c == ',');

  demand_empty_rest_of_line ();
}

#ifdef BFD_ASSEMBLER

static void SA_SET_SYM_TAGNDX PARAMS ((symbolS *, symbolS *));

#define GET_FILENAME_STRING(X) \
((char*) (&((X)->sy_symbol.ost_auxent->x_file.x_n.x_offset))[1])

/* @@ Ick.  */
static segT
fetch_coff_debug_section ()
{
  static segT debug_section;
  if (!debug_section)
    {
      CONST asymbol *s;
      s = bfd_make_debug_symbol (stdoutput, (char *) 0, 0);
      assert (s != 0);
      debug_section = s->section;
    }
  return debug_section;
}

void
SA_SET_SYM_ENDNDX (sym, val)
     symbolS *sym;
     symbolS *val;
{
  combined_entry_type *entry, *p;

  entry = &coffsymbol (symbol_get_bfdsym (sym))->native[1];
  p = coffsymbol (symbol_get_bfdsym (val))->native;
  entry->u.auxent.x_sym.x_fcnary.x_fcn.x_endndx.p = p;
  entry->fix_end = 1;
}

static void
SA_SET_SYM_TAGNDX (sym, val)
     symbolS *sym;
     symbolS *val;
{
  combined_entry_type *entry, *p;

  entry = &coffsymbol (symbol_get_bfdsym (sym))->native[1];
  p = coffsymbol (symbol_get_bfdsym (val))->native;
  entry->u.auxent.x_sym.x_tagndx.p = p;
  entry->fix_tag = 1;
}

static int
S_GET_DATA_TYPE (sym)
     symbolS *sym;
{
  return coffsymbol (symbol_get_bfdsym (sym))->native->u.syment.n_type;
}

int
S_SET_DATA_TYPE (sym, val)
     symbolS *sym;
     int val;
{
  coffsymbol (symbol_get_bfdsym (sym))->native->u.syment.n_type = val;
  return val;
}

int
S_GET_STORAGE_CLASS (sym)
     symbolS *sym;
{
  return coffsymbol (symbol_get_bfdsym (sym))->native->u.syment.n_sclass;
}

int
S_SET_STORAGE_CLASS (sym, val)
     symbolS *sym;
     int val;
{
  coffsymbol (symbol_get_bfdsym (sym))->native->u.syment.n_sclass = val;
  return val;
}

/* Merge a debug symbol containing debug information into a normal symbol.  */

void
c_symbol_merge (debug, normal)
     symbolS *debug;
     symbolS *normal;
{
  S_SET_DATA_TYPE (normal, S_GET_DATA_TYPE (debug));
  S_SET_STORAGE_CLASS (normal, S_GET_STORAGE_CLASS (debug));

  if (S_GET_NUMBER_AUXILIARY (debug) > S_GET_NUMBER_AUXILIARY (normal))
    {
      /* take the most we have */
      S_SET_NUMBER_AUXILIARY (normal, S_GET_NUMBER_AUXILIARY (debug));
    }

  if (S_GET_NUMBER_AUXILIARY (debug) > 0)
    {
      /* Move all the auxiliary information.  */
      memcpy (SYM_AUXINFO (normal), SYM_AUXINFO (debug),
	      (S_GET_NUMBER_AUXILIARY (debug)
	       * sizeof (*SYM_AUXINFO (debug))));
    }

  /* Move the debug flags.  */
  SF_SET_DEBUG_FIELD (normal, SF_GET_DEBUG_FIELD (debug));
}

void
c_dot_file_symbol (filename)
     const char *filename;
{
  symbolS *symbolP;

  /* BFD converts filename to a .file symbol with an aux entry.  It
     also handles chaining.  */
  symbolP = symbol_new (filename, bfd_abs_section_ptr, 0, &zero_address_frag);

  S_SET_STORAGE_CLASS (symbolP, C_FILE);
  S_SET_NUMBER_AUXILIARY (symbolP, 1);

  symbol_get_bfdsym (symbolP)->flags = BSF_DEBUGGING;

#ifndef NO_LISTING
  {
    extern int listing;
    if (listing)
      {
	listing_source_file (filename);
      }
  }
#endif

  /* Make sure that the symbol is first on the symbol chain */
  if (symbol_rootP != symbolP)
    {
      symbol_remove (symbolP, &symbol_rootP, &symbol_lastP);
      symbol_insert (symbolP, symbol_rootP, &symbol_rootP, &symbol_lastP);
    }				/* if not first on the list */
}

/* Line number handling */

struct line_no {
  struct line_no *next;
  fragS *frag;
  alent l;
};

int coff_line_base;

/* Symbol of last function, which we should hang line#s off of.  */
static symbolS *line_fsym;

#define in_function()		(line_fsym != 0)
#define clear_function()	(line_fsym = 0)
#define set_function(F)		(line_fsym = (F), coff_add_linesym (F))


void
coff_obj_symbol_new_hook (symbolP)
     symbolS *symbolP;
{
  long   sz = (OBJ_COFF_MAX_AUXENTRIES + 1) * sizeof (combined_entry_type);
  char * s  = (char *) xmalloc (sz);

  memset (s, 0, sz);
  coffsymbol (symbol_get_bfdsym (symbolP))->native = (combined_entry_type *) s;

  S_SET_DATA_TYPE (symbolP, T_NULL);
  S_SET_STORAGE_CLASS (symbolP, 0);
  S_SET_NUMBER_AUXILIARY (symbolP, 0);

  if (S_IS_STRING (symbolP))
    SF_SET_STRING (symbolP);

  if (S_IS_LOCAL (symbolP))
    SF_SET_LOCAL (symbolP);
}


/*
 * Handle .ln directives.
 */

static symbolS *current_lineno_sym;
static struct line_no *line_nos;
/* @@ Blindly assume all .ln directives will be in the .text section...  */
int coff_n_line_nos;

static void
add_lineno (frag, offset, num)
     fragS *frag;
     addressT offset;
     int num;
{
  struct line_no *new_line =
    (struct line_no *) xmalloc (sizeof (struct line_no));
  if (!current_lineno_sym)
    {
      abort ();
    }

#ifndef OBJ_XCOFF
  /* The native aix assembler accepts negative line number */

  if (num <= 0)
    {
      /* Zero is used as an end marker in the file.  */
      as_warn (_("Line numbers must be positive integers\n"));
      num = 1;
    }
#endif /* OBJ_XCOFF */
  new_line->next = line_nos;
  new_line->frag = frag;
  new_line->l.line_number = num;
  new_line->l.u.offset = offset;
  line_nos = new_line;
  coff_n_line_nos++;
}

void
coff_add_linesym (sym)
     symbolS *sym;
{
  if (line_nos)
    {
      coffsymbol (symbol_get_bfdsym (current_lineno_sym))->lineno =
	(alent *) line_nos;
      coff_n_line_nos++;
      line_nos = 0;
    }
  current_lineno_sym = sym;
}

static void
obj_coff_ln (appline)
     int appline;
{
  int l;

  if (! appline && def_symbol_in_progress != NULL)
    {
      as_warn (_(".ln pseudo-op inside .def/.endef: ignored."));
      demand_empty_rest_of_line ();
      return;
    }

  l = get_absolute_expression ();
  if (!appline)
    {
      add_lineno (frag_now, frag_now_fix (), l);
    }

  if (appline)
    new_logical_line ((char *) NULL, l - 1);

#ifndef NO_LISTING
  {
    extern int listing;