symbol.c

体系机构仿真

  if (fread(&fhdr, sizeof(struct ecoff_filehdr), 1, fobj) < 1)
    fatal("cannot read header from executable `%s'", fname);

  /* record endian of target */
  if (fhdr.f_magic != ECOFF_EB_MAGIC && fhdr.f_magic != ECOFF_EL_MAGIC)
    fatal("bad magic number in executable `%s'", fname);

  if (fread(&ahdr, sizeof(struct ecoff_aouthdr), 1, fobj) < 1)
    fatal("cannot read AOUT header from executable `%s'", fname);

  /* seek to the beginning of the symbolic header */
  fseek(fobj, fhdr.f_symptr, 0);

  if (fread(&symhdr, sizeof(struct ecoff_symhdr_t), 1, fobj) < 1)
    fatal("could not read symbolic header from executable `%s'", fname);

  if (symhdr.magic != ECOFF_magicSym)
    fatal("bad magic number (0x%x) in symbolic header", symhdr.magic);

  /* allocate space for the string table */
  len = symhdr.issMax + symhdr.issExtMax;
  strtab = (char *)calloc(len, sizeof(char));
  if (!strtab)
    fatal("out of virtual memory");

  /* read all the symbol names into memory */
  fseek(fobj, symhdr.cbSsOffset, 0);
  if (fread(strtab, len, 1, fobj) < 0)
    fatal("error while reading symbol table names");

  /* allocate symbol space */
  len = symhdr.isymMax + symhdr.iextMax;
  if (len <= 0)
    fatal("`%s' has no text or data symbols", fname);
  sym_db = (struct sym_sym_t *)calloc(len, sizeof(struct sym_sym_t));
  if (!sym_db)
    fatal("out of virtual memory");

  /* allocate space for the external symbol entries */
  extr =
    (struct ecoff_EXTR *)calloc(symhdr.iextMax, sizeof(struct ecoff_EXTR));
  if (!extr)
    fatal("out of virtual memory");

  fseek(fobj, symhdr.cbExtOffset, 0);
  if (fread(extr, sizeof(struct ecoff_EXTR), symhdr.iextMax, fobj) < 0)
    fatal("error reading external symbol entries");

  sym_nsyms = 0; sym_ndatasyms = 0; sym_ntextsyms = 0;

  /* convert symbols to internal format */
  for (i=0; i < symhdr.iextMax; i++)
    {
      int str_offset;

      str_offset = symhdr.issMax + extr[i].asym.iss;

#if 0
      printf("ext %2d: ifd = %2d, iss = %3d, value = %8x, st = %3x, "
	     "sc = %3x, index = %3x\n",
	     i, extr[i].ifd,
	     extr[i].asym.iss, extr[i].asym.value,
	     extr[i].asym.st, extr[i].asym.sc,
	     extr[i].asym.index);
      printf("       %08x %2d %2d %s\n",
	     extr[i].asym.value,
	     extr[i].asym.st,
	     extr[i].asym.sc,
	     &strtab[str_offset]);
#endif

      switch (extr[i].asym.st)
	{
	case ECOFF_stGlobal:
	case ECOFF_stStatic:
	  /* from data segment */
	  sym_db[sym_nsyms].name = mystrdup(&strtab[str_offset]);
	  sym_db[sym_nsyms].seg = ss_data;
	  sym_db[sym_nsyms].initialized = /* FIXME: ??? */TRUE;
	  sym_db[sym_nsyms].pub = /* FIXME: ??? */TRUE;
	  sym_db[sym_nsyms].local = /* FIXME: ??? */FALSE;
	  sym_db[sym_nsyms].addr = extr[i].asym.value;
	  sym_nsyms++;
	  sym_ndatasyms++;
	  break;

	case ECOFF_stProc:
	case ECOFF_stStaticProc:
	case ECOFF_stLabel:
	  /* from text segment */
	  sym_db[sym_nsyms].name = mystrdup(&strtab[str_offset]);
	  sym_db[sym_nsyms].seg = ss_text;
	  sym_db[sym_nsyms].initialized = /* FIXME: ??? */TRUE;
	  sym_db[sym_nsyms].pub = /* FIXME: ??? */TRUE;
	  sym_db[sym_nsyms].local = /* FIXME: ??? */FALSE;
	  sym_db[sym_nsyms].addr = extr[i].asym.value;
	  sym_nsyms++;
	  sym_ntextsyms++;
	  break;

	default:
	  /* FIXME: ignored... */;
	}
    }
  free(extr);

  /* done with the executable, close it */
  if (fclose(fobj))
    fatal("could not close executable `%s'", fname);

#endif /* BFD_LOADER */

  /*
   * generate various sortings
   */

  /* all symbols sorted by address and name */
  sym_syms =
    (struct sym_sym_t **)calloc(sym_nsyms, sizeof(struct sym_sym_t *));
  if (!sym_syms)
    fatal("out of virtual memory");

  sym_syms_by_name =
    (struct sym_sym_t **)calloc(sym_nsyms, sizeof(struct sym_sym_t *));
  if (!sym_syms_by_name)
    fatal("out of virtual memory");

  for (debug_cnt=0, i=0; i<sym_nsyms; i++)
    {
      sym_syms[debug_cnt] = &sym_db[i];
      sym_syms_by_name[debug_cnt] = &sym_db[i];
      debug_cnt++;
    }
  /* sanity check */
  if (debug_cnt != sym_nsyms)
    panic("could not locate all symbols");

  /* sort by address */
  qsort(sym_syms, sym_nsyms, sizeof(struct sym_sym_t *), (void *)acmp);

  /* sort by name */
  qsort(sym_syms_by_name, sym_nsyms, sizeof(struct sym_sym_t *), (void *)ncmp);

  /* text segment sorted by address and name */
  sym_textsyms =
    (struct sym_sym_t **)calloc(sym_ntextsyms, sizeof(struct sym_sym_t *));
  if (!sym_textsyms)
    fatal("out of virtual memory");

  sym_textsyms_by_name =
    (struct sym_sym_t **)calloc(sym_ntextsyms, sizeof(struct sym_sym_t *));
  if (!sym_textsyms_by_name)
    fatal("out of virtual memory");

  for (debug_cnt=0, i=0; i<sym_nsyms; i++)
    {
      if (sym_db[i].seg == ss_text)
	{
	  sym_textsyms[debug_cnt] = &sym_db[i];
	  sym_textsyms_by_name[debug_cnt] = &sym_db[i];
	  debug_cnt++;
	}
    }
  /* sanity check */
  if (debug_cnt != sym_ntextsyms)
    panic("could not locate all text symbols");

  /* sort by address */
  qsort(sym_textsyms, sym_ntextsyms, sizeof(struct sym_sym_t *), (void *)acmp);

  /* sort by name */
  qsort(sym_textsyms_by_name, sym_ntextsyms,
	sizeof(struct sym_sym_t *), (void *)ncmp);

  /* data segment sorted by address and name */
  sym_datasyms =
    (struct sym_sym_t **)calloc(sym_ndatasyms, sizeof(struct sym_sym_t *));
  if (!sym_datasyms)
    fatal("out of virtual memory");

  sym_datasyms_by_name =
    (struct sym_sym_t **)calloc(sym_ndatasyms, sizeof(struct sym_sym_t *));
  if (!sym_datasyms_by_name)
    fatal("out of virtual memory");

  for (debug_cnt=0, i=0; i<sym_nsyms; i++)
    {
      if (sym_db[i].seg == ss_data)
	{
	  sym_datasyms[debug_cnt] = &sym_db[i];
	  sym_datasyms_by_name[debug_cnt] = &sym_db[i];
	  debug_cnt++;
	}
    }
  /* sanity check */
  if (debug_cnt != sym_ndatasyms)
    panic("could not locate all data symbols");
      
  /* sort by address */
  qsort(sym_datasyms, sym_ndatasyms, sizeof(struct sym_sym_t *), (void *)acmp);

  /* sort by name */
  qsort(sym_datasyms_by_name, sym_ndatasyms,
	sizeof(struct sym_sym_t *), (void *)ncmp);

  /* compute symbol sizes */
  for (i=0; i<sym_ntextsyms; i++)
    {
      sym_textsyms[i]->size =
	(i != (sym_ntextsyms - 1)
	 ? (sym_textsyms[i+1]->addr - sym_textsyms[i]->addr)
	 : ((ld_text_base + ld_text_size) - sym_textsyms[i]->addr));
    }
  for (i=0; i<sym_ndatasyms; i++)
    {
      sym_datasyms[i]->size =
	(i != (sym_ndatasyms - 1)
	 ? (sym_datasyms[i+1]->addr - sym_datasyms[i]->addr)
	 : ((ld_data_base + ld_data_size) - sym_datasyms[i]->addr));
    }

  /* symbols are now available for use */
  syms_loaded = TRUE;
}

/* dump symbol SYM to output stream FD */
void
sym_dumpsym(struct sym_sym_t *sym,	/* symbol to display */
	    FILE *fd)			/* output stream */
{
  fprintf(fd,
    "sym `%s': %s seg, init-%s, pub-%s, local-%s, addr=0x%08x, size=%d\n",
	  sym->name,
	  sym->seg == ss_data ? "data" : "text",
	  sym->initialized ? "y" : "n",
	  sym->pub ? "y" : "n",
	  sym->local ? "y" : "n",
	  sym->addr,
	  sym->size);
}

/* dump all symbols to output stream FD */
void
sym_dumpsyms(FILE *fd)			/* output stream */
{
  int i;

  for (i=0; i < sym_nsyms; i++)
    sym_dumpsym(sym_syms[i], fd);
}

/* dump all symbol state to output stream FD */
void
sym_dumpstate(FILE *fd)			/* output stream */
{
  int i;

  if (fd == NULL)
    fd = stderr;

  fprintf(fd, "** All symbols sorted by address:\n");
  for (i=0; i < sym_nsyms; i++)
    sym_dumpsym(sym_syms[i], fd);

  fprintf(fd, "\n** All symbols sorted by name:\n");
  for (i=0; i < sym_nsyms; i++)
    sym_dumpsym(sym_syms_by_name[i], fd);

  fprintf(fd, "** Text symbols sorted by address:\n");
  for (i=0; i < sym_ntextsyms; i++)
    sym_dumpsym(sym_textsyms[i], fd);

  fprintf(fd, "\n** Text symbols sorted by name:\n");
  for (i=0; i < sym_ntextsyms; i++)
    sym_dumpsym(sym_textsyms_by_name[i], fd);

  fprintf(fd, "** Data symbols sorted by address:\n");
  for (i=0; i < sym_ndatasyms; i++)
    sym_dumpsym(sym_datasyms[i], fd);

  fprintf(fd, "\n** Data symbols sorted by name:\n");
  for (i=0; i < sym_ndatasyms; i++)
    sym_dumpsym(sym_datasyms_by_name[i], fd);
}

/* bind address ADDR to a symbol in symbol database DB, the address must
   match exactly if EXACT is non-zero, the index of the symbol in the
   requested symbol database is returned in *PINDEX if the pointer is
   non-NULL */
struct sym_sym_t *			/* symbol found, or NULL */
sym_bind_addr(SS_ADDR_TYPE addr,	/* address of symbol to locate */
	      int *pindex,		/* ptr to index result var */
	      int exact,		/* require exact address match? */
	      enum sym_db_t db)		/* symbol database to search */
{
  int nsyms, low, high, pos;
  struct sym_sym_t **syms;

  switch (db)
    {
    case sdb_any:
      syms = sym_syms;
      nsyms = sym_nsyms;
      break;
    case sdb_text:
      syms = sym_textsyms;
      nsyms = sym_ntextsyms;
      break;
    case sdb_data:
      syms = sym_datasyms;
      nsyms = sym_ndatasyms;
      break;
    default:
      panic("bogus symbol database");
    }

  /* any symbols to search? */
  if (!nsyms)
    {
      if (pindex)
	*pindex = -1;
      return NULL;
    }

  /* binary search symbol database (sorted by address) */
  low = 0;
  high = nsyms-1;
  pos = (low + high) >> 1;
  while (!(/* exact match */
	   (exact && syms[pos]->addr == addr)
	   /* in bounds match */
	   || (!exact
	       && syms[pos]->addr <= addr
	       && addr < (syms[pos]->addr + MAX(1, syms[pos]->size)))))
    {
      if (addr < syms[pos]->addr)
	high = pos - 1;
      else
	low = pos + 1;
      if (high >= low)
	pos = (low + high) >> 1;
      else
	{
	  if (pindex)
	    *pindex = -1;
	  return NULL;
	}
    }

  /* bound! */
  if (pindex)
    *pindex = pos;
  return syms[pos];
}

/* bind name NAME to a symbol in symbol database DB, the index of the symbol
   in the requested symbol database is returned in *PINDEX if the pointer is
   non-NULL */
struct sym_sym_t *				/* symbol found, or NULL */
sym_bind_name(char *name,			/* symbol name to locate */
	      int *pindex,			/* ptr to index result var */
	      enum sym_db_t db)			/* symbol database to search */
{
  int nsyms, low, high, pos, cmp;
  struct sym_sym_t **syms;

  switch (db)
    {
    case sdb_any:
      syms = sym_syms_by_name;
      nsyms = sym_nsyms;
      break;
    case sdb_text:
      syms = sym_textsyms_by_name;
      nsyms = sym_ntextsyms;
      break;
    case sdb_data:
      syms = sym_datasyms_by_name;
      nsyms = sym_ndatasyms;
      break;
    default:
      panic("bogus symbol database");
    }

  /* any symbols to search? */
  if (!nsyms)
    {
      if (pindex)
	*pindex = -1;
      return NULL;
    }

  /* binary search symbol database (sorted by name) */
  low = 0;
  high = nsyms-1;
  pos = (low + high) >> 1;
  while (!(/* exact string match */!(cmp = strcmp(syms[pos]->name, name))))
    {
      if (cmp > 0)
	high = pos - 1;
      else
	low = pos + 1;
      if (high >= low)
	pos = (low + high) >> 1;
      else
	{
	  if (pindex)
	    *pindex = -1;
	  return NULL;
	}
    }

  /* bound! */
  if (pindex)
    *pindex = pos;
  return syms[pos];
}