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/* loader-dld_link.c -- dynamic linking with dld |
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|
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Copyright (C) 1998-2000, 2004, 2006-2008, 2011-2014 Free Software |
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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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} |
