ltdl.c

Small Device C Compiler 面向Inter8051

	      *end = 0; /* set a temporary string terminator */
	      if (strncmp(p, "-l", 2) == 0)
		{
		  size_t name_len = 3+ /* "lib" */ LT_STRLEN (p + 2);
		  name = LT_EMALLOC (char, 1+ name_len);
		  if (name)
		    sprintf (name, "lib%s", p+2);
		}
	      else
		name = lt_estrdup(p);

	      if (!name)
		goto cleanup_names;

	      names[depcount++] = name;
	      *end = save;
	    }
	  p = end;
	}
    }

  /* load the deplibs (in reverse order)
     At this stage, don't worry if the deplibs do not load correctly,
     they may already be statically linked into the loading application
     for instance.  There will be a more enlightening error message
     later on if the loaded module cannot resolve all of its symbols.  */
  if (depcount)
    {
      int	j = 0;

      handle->deplibs = (lt_dlhandle*) LT_EMALLOC (lt_dlhandle *, depcount);
      if (!handle->deplibs)
	goto cleanup;

      for (i = 0; i < depcount; ++i)
	{
	  handle->deplibs[j] = lt_dlopenext(names[depcount-1-i]);
	  if (handle->deplibs[j])
	    {
	      ++j;
	    }
	}

      handle->depcount	= j;	/* Number of successfully loaded deplibs */
      errors		= 0;
    }

 cleanup_names:
  for (i = 0; i < depcount; ++i)
    {
      LT_DLFREE (names[i]);
    }

 cleanup:
  LT_DLFREE (names);
#endif

  return errors;
}

static int
unload_deplibs (handle)
     lt_dlhandle handle;
{
  int i;
  int errors = 0;

  if (handle->depcount)
    {
      for (i = 0; i < handle->depcount; ++i)
	{
	  if (!LT_DLIS_RESIDENT (handle->deplibs[i]))
	    {
	      errors += lt_dlclose (handle->deplibs[i]);
	    }
	}
    }

  return errors;
}

static int
trim (dest, str)
     char **dest;
     const char *str;
{
  /* remove the leading and trailing "'" from str
     and store the result in dest */
  const char *end   = strrchr (str, '\'');
  size_t len	    = LT_STRLEN (str);
  char *tmp;

  LT_DLFREE (*dest);

  if (len > 3 && str[0] == '\'')
    {
      tmp = LT_EMALLOC (char, end - str);
      if (!tmp)
	return 1;

      strncpy(tmp, &str[1], (end - str) - 1);
      tmp[len-3] = LT_EOS_CHAR;
      *dest = tmp;
    }
  else
    {
      *dest = 0;
    }

  return 0;
}

static int
free_vars (dlname, oldname, libdir, deplibs)
     char *dlname;
     char *oldname;
     char *libdir;
     char *deplibs;
{
  LT_DLFREE (dlname);
  LT_DLFREE (oldname);
  LT_DLFREE (libdir);
  LT_DLFREE (deplibs);

  return 0;
}

static int
try_dlopen (phandle, filename)
     lt_dlhandle *phandle;
     const char *filename;
{
  const char *	ext		= 0;
  const char *	saved_error	= 0;
  char *	canonical	= 0;
  char *	base_name	= 0;
  char *	dir		= 0;
  char *	name		= 0;
  int		errors		= 0;
  lt_dlhandle	newhandle;

  assert (phandle);
  assert (*phandle == 0);

  LT_DLMUTEX_GETERROR (saved_error);

  /* dlopen self? */
  if (!filename)
    {
      *phandle = (lt_dlhandle) LT_EMALLOC (struct lt_dlhandle_struct, 1);
      if (*phandle == 0)
	return 1;

      memset (*phandle, 0, sizeof(struct lt_dlhandle_struct));
      newhandle	= *phandle;

      /* lt_dlclose()ing yourself is very bad!  Disallow it.  */
      LT_DLSET_FLAG (*phandle, LT_DLRESIDENT_FLAG);

      if (tryall_dlopen (&newhandle, 0) != 0)
	{
	  LT_DLFREE (*phandle);
	  return 1;
	}

      goto register_handle;
    }

  assert (filename && *filename);

  /* Doing this immediately allows internal functions to safely
     assume only canonicalized paths are passed.  */
  if (canonicalize_path (filename, &canonical) != 0)
    {
      ++errors;
      goto cleanup;
    }

  /* If the canonical module name is a path (relative or absolute)
     then split it into a directory part and a name part.  */
  base_name = strrchr (canonical, '/');
  if (base_name)
    {
      size_t dirlen = (1+ base_name) - canonical;

      dir = LT_EMALLOC (char, 1+ dirlen);
      if (!dir)
	{
	  ++errors;
	  goto cleanup;
	}

      strncpy (dir, canonical, dirlen);
      dir[dirlen] = LT_EOS_CHAR;

      ++base_name;
    }
  else
    LT_DLMEM_REASSIGN (base_name, canonical);

  assert (base_name && *base_name);

  /* Check whether we are opening a libtool module (.la extension).  */
  ext = strrchr (base_name, '.');
  if (ext && strcmp (ext, archive_ext) == 0)
    {
      /* this seems to be a libtool module */
      FILE *	file	 = 0;
      char *	dlname	 = 0;
      char *	old_name = 0;
      char *	libdir	 = 0;
      char *	deplibs	 = 0;
      char *    line	 = 0;
      size_t	line_len;

      /* if we can't find the installed flag, it is probably an
	 installed libtool archive, produced with an old version
	 of libtool */
      int	installed = 1;

      /* extract the module name from the file name */
      name = LT_EMALLOC (char, ext - base_name + 1);
      if (!name)
	{
	  ++errors;
	  goto cleanup;
	}

      /* canonicalize the module name */
      {
        size_t i;
        for (i = 0; i < ext - base_name; ++i)
	  {
	    if (isalnum ((int)(base_name[i])))
	      {
	        name[i] = base_name[i];
	      }
	    else
	      {
	        name[i] = '_';
	      }
	  }
        name[ext - base_name] = LT_EOS_CHAR;
      }

      /* Now try to open the .la file.  If there is no directory name
         component, try to find it first in user_search_path and then other
         prescribed paths.  Otherwise (or in any case if the module was not
         yet found) try opening just the module name as passed.  */
      if (!dir)
	{
	  const char *search_path;

	  LT_DLMUTEX_LOCK ();
	  search_path = user_search_path;
	  if (search_path)
	    file = find_file (user_search_path, base_name, &dir);
	  LT_DLMUTEX_UNLOCK ();

	  if (!file)
	    {
	      search_path = getenv (LTDL_SEARCHPATH_VAR);
	      if (search_path)
		file = find_file (search_path, base_name, &dir);
	    }

#ifdef LTDL_SHLIBPATH_VAR
	  if (!file)
	    {
	      search_path = getenv (LTDL_SHLIBPATH_VAR);
	      if (search_path)
		file = find_file (search_path, base_name, &dir);
	    }
#endif
#ifdef LTDL_SYSSEARCHPATH
	  if (!file && sys_search_path)
	    {
	      file = find_file (sys_search_path, base_name, &dir);
	    }
#endif
	}
      if (!file)
	{
	  file = fopen (filename, LT_READTEXT_MODE);
	}

      /* If we didn't find the file by now, it really isn't there.  Set
	 the status flag, and bail out.  */
      if (!file)
	{
	  LT_DLMUTEX_SETERROR (LT_DLSTRERROR (FILE_NOT_FOUND));
	  ++errors;
	  goto cleanup;
	}

      line_len = LT_FILENAME_MAX;
      line = LT_EMALLOC (char, line_len);
      if (!line)
	{
	  fclose (file);
	  ++errors;
	  goto cleanup;
	}

      /* read the .la file */
      while (!feof (file))
	{
	  if (!fgets (line, (int) line_len, file))
	    {
	      break;
	    }

	  /* Handle the case where we occasionally need to read a line
	     that is longer than the initial buffer size.  */
	  while (line[LT_STRLEN(line) -1] != '\n')
	    {
	      line = LT_DLREALLOC (char, line, line_len *2);
	      if (!fgets (&line[line_len -1], (int) line_len +1, file))
		{
		  break;
		}
	      line_len *= 2;
	    }

	  if (line[0] == '\n' || line[0] == '#')
	    {
	      continue;
	    }

#undef  STR_DLNAME
#define STR_DLNAME	"dlname="
	  if (strncmp (line, STR_DLNAME, sizeof (STR_DLNAME) - 1) == 0)
	    {
	      errors += trim (&dlname, &line[sizeof (STR_DLNAME) - 1]);
	    }

#undef  STR_OLD_LIBRARY
#define STR_OLD_LIBRARY	"old_library="
	  else if (strncmp (line, STR_OLD_LIBRARY,
			    sizeof (STR_OLD_LIBRARY) - 1) == 0)
	    {
	      errors += trim (&old_name, &line[sizeof (STR_OLD_LIBRARY) - 1]);
	    }
#undef  STR_LIBDIR
#define STR_LIBDIR	"libdir="
	  else if (strncmp (line, STR_LIBDIR, sizeof (STR_LIBDIR) - 1) == 0)
	    {
	      errors += trim (&libdir, &line[sizeof(STR_LIBDIR) - 1]);
	    }

#undef  STR_DL_DEPLIBS
#define STR_DL_DEPLIBS	"dependency_libs="
	  else if (strncmp (line, STR_DL_DEPLIBS,
			    sizeof (STR_DL_DEPLIBS) - 1) == 0)
	    {
	      errors += trim (&deplibs, &line[sizeof (STR_DL_DEPLIBS) - 1]);
	    }
	  else if (strcmp (line, "installed=yes\n") == 0)
	    {
	      installed = 1;
	    }
	  else if (strcmp (line, "installed=no\n") == 0)
	    {
	      installed = 0;
	    }

#undef  STR_LIBRARY_NAMES
#define STR_LIBRARY_NAMES "library_names="
	  else if (! dlname && strncmp (line, STR_LIBRARY_NAMES,
					sizeof (STR_LIBRARY_NAMES) - 1) == 0)
	    {
	      char *last_libname;
	      errors += trim (&dlname, &line[sizeof (STR_LIBRARY_NAMES) - 1]);
	      if (!errors
		  && dlname
		  && (last_libname = strrchr (dlname, ' ')) != 0)
		{
		  last_libname = lt_estrdup (last_libname + 1);
		  if (!last_libname)
		    {
		      ++errors;
		      goto cleanup;
		    }
		  LT_DLMEM_REASSIGN (dlname, last_libname);
		}
	    }

	  if (errors)
	    break;
	}

      fclose (file);
      LT_DLFREE (line);

      /* allocate the handle */
      *phandle = (lt_dlhandle) LT_EMALLOC (struct lt_dlhandle_struct, 1);
      if (*phandle == 0)
	++errors;

      if (errors)
	{
	  free_vars (dlname, old_name, libdir, deplibs);
	  LT_DLFREE (*phandle);
	  goto cleanup;
	}

      assert (*phandle);

      memset (*phandle, 0, sizeof(struct lt_dlhandle_struct));
      if (load_deplibs (*phandle, deplibs) == 0)
	{
	  newhandle = *phandle;
	  /* find_module may replace newhandle */
	  if (find_module (&newhandle, dir, libdir, dlname, old_name, installed))
	    {
	      unload_deplibs (*phandle);
	      ++errors;
	    }
	}
      else
	{
	  ++errors;
	}

      free_vars (dlname, old_name, libdir, deplibs);
      if (errors)
	{
	  LT_DLFREE (*phandle);
	  goto cleanup;
	}

      if (*phandle != newhandle)
	{
	  unload_deplibs (*phandle);
	}
    }
  else
    {
      /* not a libtool module */
      *phandle = (lt_dlhandle) LT_EMALLOC (struct lt_dlhandle_struct, 1);
      if (*phandle == 0)
	{
	  ++errors;
	  goto cleanup;
	}

      memset (*phandle, 0, sizeof (struct lt_dlhandle_struct));
      newhandle = *phandle;

      /* If the module has no directory name component, try to find it
	 first in user_search_path and then other prescribed paths.
	 Otherwise (or in any case if the module was not yet found) try
	 opening just the module name as passed.  */
      if ((dir || (!find_handle (user_search_path, base_name, &newhandle)
		   && !find_handle (getenv (LTDL_SEARCHPATH_VAR), base_name,
				    &newhandle)
#ifdef LTDL_SHLIBPATH_VAR
		   && !find_handle (getenv (LTDL_SHLIBPATH_VAR), base_name,
				    &newhandle)
#endif
#ifdef LTDL_SYSSEARCHPATH
		   && !find_handle (sys_search_path, base_name, &newhandle)
#endif
		   )))
	{
	  tryall_dlopen (&newhandle, filename);
	}

      if (!newhandle)
	{
	  LT_DLFREE (*phandle);
	  ++errors;
	  goto cleanup;
	}
    }

 register_handle:
  LT_DLMEM_REASSIGN (*phandle, newhandle);

  if ((*phandle)->info.ref_count == 0)
    {
      (*phandle)->info.ref_count	= 1;
      LT_DLMEM_REASSIGN ((*phandle)->info.name, name);

      LT_DLMUTEX_LOCK ();
      (*phandle)->next		= handles;
      handles			= *phandle;
      LT_DLMUTEX_UNLOCK ();
    }

  LT_DLMUTEX_SETERROR (saved_error);

 cleanup:
  LT_DLFREE (dir);
  LT_DLFREE (name);
  LT_DLFREE (canonical);

  return errors;
}

lt_dlhandle
lt_dlopen (filename)
     const char *filename;
{
  lt_dlhandle handle = 0;

  /* Just incase we missed a code path in try_dlopen() that reports
     an error, but forgets to reset handle... */
  if (try_dlopen (&handle, filename) != 0)
    return 0;

  return handle;
}

/* If the last error messge store was `FILE_NOT_FOUND', then return
   non-zero.  */
static int
file_not_found ()
{
  const char *error = 0;

  LT_DLMUTEX_GETERROR (error);
  if (error == LT_DLSTRERROR (FILE_NOT_FOUND))
    return 1;

  return 0;
}

/* If FILENAME has an ARCHIVE_EXT or SHLIB_EXT extension, try to
   open the FILENAME as passed.  Otherwise try appending ARCHIVE_EXT,
   and if a file is still not found try again with SHLIB_EXT appended
   instead.  */
lt_dlhandle
lt_dlopenext (filename)
     const char *filename;
{
  lt_dlhandle	handle		= 0;
  char *	tmp		= 0;
  char *	ext		= 0;
  size_t	len;
  int		errors		= 0;

  if (!filename)
    {
      return lt_dlopen (filename);
    }

  assert (filename);

  len = LT_STRLEN (filename);
  ext = strrchr (filename, '.');

  /* If FILENAME already bears a suitable extension, there is no need
     to try appending additional extensions.  */
  if (ext && ((strcmp (ext, archive_ext) == 0)
#ifdef LTDL_SHLIB_EXT
	      || (strcmp (ext, shlib_ext) == 0)
#endif
      ))
    {
      return lt_dlopen (filename);
    }

  /* First try appending ARCHIVE_EXT.  */
  tmp = LT_EMALLOC (char, len + LT_STRLEN (archive_ext) + 1);
  if (!tmp)
    return 0;

  strcpy (tmp, filename);
  strcat (tmp, archive_ext);
  errors = try_dlopen (&handle, tmp);

  /* If we found FILENAME, stop searching -- whether we were able to
     load the file as a module or not.  If the file exists but loading
     failed, it is better to return an error message here than to
     report FILE_NOT_FOUND when the alternatives (foo.so etc) are not
     in the module search path.  */
  if (handle || ((errors > 0) && file_not_found ()))
    {
      LT_DLFREE (tmp);
      return handle;
    }

#ifdef LTDL_SHLIB_EXT
  /* Try appending SHLIB_EXT.   */
  if (LT_STRLEN (shlib_ext) > LT_STRLEN (archive_ext))
    {
      LT_DLFREE (tmp);
      tmp = LT_EMALLOC (char, len + LT_STRLEN (shlib_ext) + 1);
      if (!tmp)
	return 0;

      strcpy (tmp, filename);
    }
  else
    {
      tmp[len] = LT_EOS_CHAR;
    }

  strcat(tmp, shlib_ext);