ltdl.c

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      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, '\'');
  int	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;
}

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;
      int	i;

      /* 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 */
      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, 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], 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.  */
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;
  int		len;
  int		errors		= 0;
  int		file_found	= 1; /* until proven otherwise */

  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);
  errors = try_dlopen (&handle, tmp);

  /* As before, if the file was found but loading failed, return now
     with the current error message.  */
  if (handle || ((errors > 0) && file_not_found ()))
    {
      LT_DLFREE (tmp);
      return handle;
    }
#endif

  /* Still here?  Then we really did fail to locate any of the file
     names we tried.  */
  LT_DLMUTEX_SETERROR (LT_DLSTRERROR (FILE_NOT_FOUND));
  LT_DLFREE (tmp);
  return 0;
}


int
lt_argz_insert (pargz, pargz_len, before, entry)
     char **pargz;
     size_t *pargz_len;
     char *before;
     const char *entry;
{
  error_t error;

  if ((error = argz_insert (pargz, pargz_len, before, entry)))
    {
      switch (error)
	{
	case ENOMEM:
	  LT_DLMUTEX_SETERROR (LT_DLSTRERROR (NO_MEMORY));
	  break;
	default:
	  LT_DLMUTEX_SETERROR (LT_DLSTRERROR (UNKNOWN));
	  break;
	}
      return 1;
    }

  return 0;
}

int
lt_argz_