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- Change the strong dlfcn names in libc to ___name, and make the __name
  versions used by others in libc weak, so that we have:
	name: weak
	__name: weak
	___name: strong
- Add __name strong aliases of the dlfcn names in ld.elf_so, so that we have:
	name: strong
	__name: strong

This allows ld.elf_so to self-resolve both the name and __name variants
of the dlfcn functions, the former being required for dlfcn support in
applications, the latter being required for dlfcn support in libc.

Fixes the problem described in:

    http://mail-index.netbsd.org/tech-toolchain/2004/07/17/0000.html

Reviewed by Nick.

/*	$NetBSD: dlfcn_elf.c,v 1.5 2004/07/18 17:26:19 thorpej Exp $	*/

/*
 * Copyright (c) 2000 Takuya SHIOZAKI
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: dlfcn_elf.c,v 1.5 2004/07/18 17:26:19 thorpej Exp $");
#endif /* LIBC_SCCS and not lint */

#include "namespace.h"

#undef dlopen
#undef dlclose
#undef dlsym
#undef dlerror
#undef dladdr

#define	dlopen		___dlopen
#define	dlclose		___dlclose
#define	dlsym		___dlsym
#define	dlerror		___dlerror
#define	dladdr		___dladdr

#define ELFSIZE ARCH_ELFSIZE
#include "rtld.h"

#ifdef __weak_alias
__weak_alias(dlopen,___dlopen)
__weak_alias(dlclose,___dlclose)
__weak_alias(dlsym,___dlsym)
__weak_alias(dlerror,___dlerror)
__weak_alias(dladdr,___dladdr)

__weak_alias(__dlopen,___dlopen)
__weak_alias(__dlclose,___dlclose)
__weak_alias(__dlsym,___dlsym)
__weak_alias(__dlerror,___dlerror)
__weak_alias(__dladdr,___dladdr)
#endif

/*
 * For ELF, the dynamic linker directly resolves references to its
 * services to functions inside the dynamic linker itself.  These
 * weak-symbol stubs are necessary so that "ld" won't complain about
 * undefined symbols.  The stubs are executed only when the program is
 * linked statically, or when a given service isn't implemented in the
 * dynamic linker.  They must return an error if called, and they must
 * be weak symbols so that the dynamic linker can override them.
 */

static char dlfcn_error[] = "Service unavailable";

/*ARGSUSED*/
void *
dlopen(const char *name, int mode)
{

	return NULL;
}

/*ARGSUSED*/
int
dlclose(void *fd)
{

	return -1;
}

/*ARGSUSED*/
void *
dlsym(void *handle, const char *name)
{

	return NULL;
}

/*ARGSUSED*/
__aconst char *
dlerror()
{

	return dlfcn_error;
}

/*ARGSUSED*/
int
dladdr(const void *addr, Dl_info *dli)
{

	return 0;
}