libasm/asm_newsym.c

/* Define new symbol for current position in given section.
   Copyright (C) 2002, 2005 Red Hat, Inc.
   Written by Ulrich Drepper <drepper@redhat.com>, 2002.

   This program is Open Source software; you can redistribute it and/or
   modify it under the terms of the Open Software License version 1.0 as
   published by the Open Source Initiative.

   You should have received a copy of the Open Software License along
   with this program; if not, you may obtain a copy of the Open Software
   License version 1.0 from http://www.opensource.org/licenses/osl.php or
   by writing the Open Source Initiative c/o Lawrence Rosen, Esq.,
   3001 King Ranch Road, Ukiah, CA 95482.   */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <libasmP.h>
#include <system.h>


AsmSym_t *
asm_newsym (asmscn, name, size, type, binding)
     AsmScn_t *asmscn;
     const char *name;
     GElf_Xword size;
     int type;
     int binding;
{
#define TEMPSYMLEN 10
  char tempsym[TEMPSYMLEN];
  AsmSym_t *result;

  if (asmscn == NULL)
    /* Something went wrong before.  */
    return NULL;

  /* Generate a temporary symbol if necessary.  */
  if (name == NULL)
    {
      /* If a local symbol name is created the symbol better have
	 local binding.  */
      if (binding != STB_LOCAL)
	{
	  __libasm_seterrno (ASM_E_INVALID);
	  return NULL;
	}

      // XXX This requires getting the format from the machine backend.  */
      snprintf (tempsym, TEMPSYMLEN, ".L%07u", asmscn->ctx->tempsym_count++);

      name = tempsym;
    }

  size_t name_len = strlen (name) + 1;

  result = (AsmSym_t *) malloc (sizeof (AsmSym_t) + name_len);
  if (result == NULL)
    return NULL;

  rwlock_wrlock (asmscn->ctx->lock);

  result->scn = asmscn;
  result->offset = asmscn->offset;
  result->size = size;
  result->type = type;
  result->binding = binding;
  result->symidx = 0;
  result->strent = ebl_strtabadd (asmscn->ctx->symbol_strtab,
				  memcpy (result + 1, name, name_len), 0);

  if (unlikely (asmscn->ctx->textp))
    {
      /* We are only interested in the name and don't need to know whether
	 it is a local name or not.  */
      /* First print the binding pseudo-op.  */
      if (binding == STB_GLOBAL)
	fprintf (asmscn->ctx->out.file, "\t.globl\t%s\n", name);
      else if (binding == STB_WEAK)
	fprintf (asmscn->ctx->out.file, "\t.weak\t%s\n", name);

      /* Next the symbol type.  */
      if (type == STT_OBJECT)
	fprintf (asmscn->ctx->out.file, "\t.type\t%s,@object\n", name);
      else if (type == STT_FUNC)
	fprintf (asmscn->ctx->out.file, "\t.type\t%s,@function\n", name);

      /* Finally the size and the label.  */
      fprintf (asmscn->ctx->out.file, "\t.size\t%s,%" PRIuMAX "\n%s:\n",
	       name, (uintmax_t) size, name);
    }
  else
    {
      /* Put the symbol in the hash table so that we can later find it.  */
      if (asm_symbol_tab_insert (&asmscn->ctx->symbol_tab, elf_hash (name),
				 result) != 0)
	{
	  /* The symbol already exists.  */
	  __libasm_seterrno (ASM_E_DUPLSYM);
	  /* Note that we can free the entry since there must be no
	     reference in the string table to the string.  We can only
	     fail to insert the symbol into the symbol table if there
	     is already a symbol with this name.  In this case the
	     ebl_strtabadd function would use the previously provided
	     name.  */
	  free (result);
	  result = NULL;
	}
      else if (name != tempsym && asm_emit_symbol_p (name))
	/* Only count non-private symbols.  */
	++asmscn->ctx->nsymbol_tab;
    }

  rwlock_unlock (asmscn->ctx->lock);

  return result;
}