159 lines
		
	
	
		
			4.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			159 lines
		
	
	
		
			4.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* loader-dld_link.c -- dynamic linking with dld
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| 
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|    Copyright (C) 1998, 1999, 2000, 2004, 2006,
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|                  2007, 2008 Free Software Foundation, Inc.
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|    Written by Thomas Tanner, 1998
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| 
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|    NOTE: The canonical source of this file is maintained with the
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|    GNU Libtool package.  Report bugs to bug-libtool@gnu.org.
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| 
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| GNU Libltdl is free software; you can redistribute it and/or
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| modify it under the terms of the GNU Lesser General Public
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| License as published by the Free Software Foundation; either
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| version 2 of the License, or (at your option) any later version.
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| 
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| As a special exception to the GNU Lesser General Public License,
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| if you distribute this file as part of a program or library that
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| is built using GNU Libtool, you may include this file under the
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| same distribution terms that you use for the rest of that program.
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| 
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| GNU Libltdl is distributed in the hope that it will be useful,
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| but WITHOUT ANY WARRANTY; without even the implied warranty of
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| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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| GNU Lesser General Public License for more details.
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| 
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| You should have received a copy of the GNU Lesser General Public
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| License along with GNU Libltdl; see the file COPYING.LIB.  If not, a
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| copy can be downloaded from  http://www.gnu.org/licenses/lgpl.html,
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| or obtained by writing to the Free Software Foundation, Inc.,
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| 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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| */
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| 
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| #include "lt__private.h"
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| #include "lt_dlloader.h"
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| 
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| /* Use the preprocessor to rename non-static symbols to avoid namespace
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|    collisions when the loader code is statically linked into libltdl.
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|    Use the "<module_name>_LTX_" prefix so that the symbol addresses can
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|    be fetched from the preloaded symbol list by lt_dlsym():  */
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| #define get_vtable	dld_link_LTX_get_vtable
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| 
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| LT_BEGIN_C_DECLS
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| LT_SCOPE lt_dlvtable *get_vtable (lt_user_data loader_data);
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| LT_END_C_DECLS
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| 
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| 
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| /* Boilerplate code to set up the vtable for hooking this loader into
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|    libltdl's loader list:  */
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| static int	 vl_exit  (lt_user_data loader_data);
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| static lt_module vm_open  (lt_user_data loader_data, const char *filename,
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|                            lt_dladvise advise);
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| static int	 vm_close (lt_user_data loader_data, lt_module module);
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| static void *	 vm_sym   (lt_user_data loader_data, lt_module module,
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| 			  const char *symbolname);
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| 
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| static lt_dlvtable *vtable = 0;
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| 
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| /* Return the vtable for this loader, only the name and sym_prefix
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|    attributes (plus the virtual function implementations, obviously)
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|    change between loaders.  */
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| lt_dlvtable *
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| get_vtable (lt_user_data loader_data)
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| {
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|   if (!vtable)
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|     {
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|       vtable = lt__zalloc (sizeof *vtable);
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|     }
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| 
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|   if (vtable && !vtable->name)
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|     {
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|       vtable->name		= "lt_dld_link";
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|       vtable->module_open	= vm_open;
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|       vtable->module_close	= vm_close;
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|       vtable->find_sym		= vm_sym;
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|       vtable->dlloader_exit	= vl_exit;
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|       vtable->dlloader_data	= loader_data;
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|       vtable->priority		= LT_DLLOADER_APPEND;
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|     }
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| 
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|   if (vtable && (vtable->dlloader_data != loader_data))
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|     {
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|       LT__SETERROR (INIT_LOADER);
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|       return 0;
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|     }
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| 
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|   return vtable;
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| }
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| 
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| 
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| 
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| /* --- IMPLEMENTATION --- */
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| 
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| 
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| #if defined(HAVE_DLD_H)
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| #  include <dld.h>
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| #endif
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| 
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| /* A function called through the vtable when this loader is no
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|    longer needed by the application.  */
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| static int
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| vl_exit (lt_user_data LT__UNUSED loader_data)
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| {
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|   vtable = NULL;
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|   return 0;
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| }
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| 
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| /* A function called through the vtable to open a module with this
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|    loader.  Returns an opaque representation of the newly opened
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|    module for processing with this loader's other vtable functions.  */
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| static lt_module
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| vm_open (lt_user_data LT__UNUSED loader_data, const char *filename,
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|          lt_dladvise LT__UNUSED advise)
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| {
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|   lt_module module = lt__strdup (filename);
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| 
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|   if (dld_link (filename) != 0)
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|     {
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|       LT__SETERROR (CANNOT_OPEN);
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|       FREE (module);
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|     }
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| 
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|   return module;
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| }
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| 
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| /* A function called through the vtable when a particular module
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|    should be unloaded.  */
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| static int
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| vm_close (lt_user_data LT__UNUSED loader_data, lt_module module)
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| {
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|   int errors = 0;
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| 
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|   if (dld_unlink_by_file ((char*)(module), 1) != 0)
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|     {
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|       LT__SETERROR (CANNOT_CLOSE);
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|       ++errors;
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|     }
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|   else
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|     {
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|       FREE (module);
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|     }
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| 
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|   return errors;
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| }
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| 
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| /* A function called through the vtable to get the address of
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|    a symbol loaded from a particular module.  */
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| static void *
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| vm_sym (lt_user_data LT__UNUSED loader_data, lt_module LT__UNUSED module,
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| 	const char *name)
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| {
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|   void *address = dld_get_func (name);
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| 
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|   if (!address)
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|     {
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|       LT__SETERROR (SYMBOL_NOT_FOUND);
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|     }
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| 
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|   return address;
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| }
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