Re: make libltdl work on platforms without loader

[Ralf Wildenhues]

* Gary V. Vaughan wrote on Sun, Nov 28, 2004 at 01:31:52PM CET:
> Ralf Wildenhues wrote:
> 
> >     * libltdl/loaders/dummy.c: new file, dummy loader that doesn't
> >        do anything and always fails.
> >     * m4/ltdl.m4 (LT_LIB_DLLOAD), libltdl/loaders/Makefile.am:
> >     In case of no other loader, use the dummy loader to force
> >     symfileobj creation.
> 
> Yuck!  No, I think we should fix this properly from the outset.  It 
> should only be a matter of #defining it away under the right 
> circumstances...

Yup.  That turned out to be pretty easy, too.  See below.

> I expect we'll need to fix the annoying need-a-.la-file-even-to-dlopen-
> a-preloaded-module bug too :-(

Do you mean the issue that currently prevents libdlloader.la from
being convenience-only?  Haven't looked yet, but might soon.


Back to above (rightfully) rejected patch.  This one seems to do
the trick.  Not beautiful, but much shorter.  OK to apply?  Does
HAVE_NO_DLLOADER constitute disallowed infringement on autoconf
namespace?

Regards,
Ralf    (what about my dietlibc patches?)


        * m4/ltdl.m4 (LT_LIB_DLLOAD): Define HAVE_NO_DLLOADER in case
        preopen is the only thing we got.
        * libltdl/ltdl.c (lt_dlinit): Do not preload if
        !HAVE_NO_DLLOADER.  Do not declare preloaded_symbols then.
        Fixes libltdl on static platforms.


Index: libltdl/ltdl.c
===================================================================
RCS file: /cvsroot/libtool/libtool/libltdl/ltdl.c,v
retrieving revision 1.217.2.3
diff -u -r1.217.2.3 ltdl.c
--- libltdl/ltdl.c      1 Nov 2004 14:05:02 -0000       1.217.2.3
+++ libltdl/ltdl.c      28 Nov 2004 19:01:56 -0000
@@ -189,7 +189,9 @@
 #define preloaded_symbols      LT_CONC3(lt_, LTDLOPEN, _LTX_preloaded_symbols)
 
 LT_SCOPE const lt_dlvtable *   get_vtable (lt_user_data data);
+#ifndef HAVE_NO_DLLOADER
 LT_SCOPE lt_dlsymlist          preloaded_symbols;
+#endif
 
 /* Initialize libltdl. */
 int
@@ -211,6 +213,7 @@
 
       /* Now open all the preloaded module loaders, so the application
         can use _them_ to lt_dlopen its own modules.  */
+#ifndef HAVE_NO_DLLOADER
       if (!errors)
        {
          errors += lt_dlpreload (&preloaded_symbols);
@@ -220,6 +223,7 @@
        {
          errors += lt_dlpreload_open (LT_STR(LTDLOPEN), loader_init_callback);
        }
+#endif /* !HAVE_NO_DLLOADER */
     }
 
   return errors;
Index: m4/ltdl.m4
===================================================================
RCS file: /cvsroot/libtool/libtool/m4/ltdl.m4,v
retrieving revision 1.20.2.2
diff -u -r1.20.2.2 ltdl.m4
--- m4/ltdl.m4  10 Nov 2004 13:20:52 -0000      1.20.2.2
+++ m4/ltdl.m4  28 Nov 2004 19:02:03 -0000
@@ -413,7 +413,9 @@
                [AC_DEFINE([HAVE_LIBDL], [1],
                         [Define if you have the libdl library or equivalent.])
                LIBADD_DLOPEN="-lsvld" libltdl_cv_func_dlopen="yes"
-               LT_DLLOADERS="$LT_DLLOADERS dlopen.la"])])])
+               LT_DLLOADERS="$LT_DLLOADERS dlopen.la"],
+               [AC_DEFINE([HAVE_NO_DLLOADER], [1],
+                          [Define if no native dlloader present on this 
platform.])])])])
 if test x"$libltdl_cv_func_dlopen" = xyes || test x"$libltdl_cv_lib_dl_dlopen" 
= xyes
 then
   lt_save_LIBS="$LIBS"