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/* loader-shl_load.c -- dynamic linking with shl_load (HP-UX) |
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|
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Copyright (C) 1998-2000, 2004, 2006-2008, 2011-2015 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 shl_load_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_shl_load"; |
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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_DL_H |
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# include <dl.h> |
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#endif |
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|
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/* some flags are missing on some systems, so we provide |
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* harmless defaults. |
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* |
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* Mandatory: |
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* BIND_IMMEDIATE - Resolve symbol references when the library is loaded. |
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* BIND_DEFERRED - Delay code symbol resolution until actual reference. |
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* |
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* Optionally: |
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* BIND_FIRST - Place the library at the head of the symbol search |
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* order. |
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* BIND_NONFATAL - The default BIND_IMMEDIATE behavior is to treat all |
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* unsatisfied symbols as fatal. This flag allows |
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* binding of unsatisfied code symbols to be deferred |
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* until use. |
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* [Perl: For certain libraries, like DCE, deferred |
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* binding often causes run time problems. Adding |
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* BIND_NONFATAL to BIND_IMMEDIATE still allows |
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* unresolved references in situations like this.] |
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* BIND_NOSTART - Do not call the initializer for the shared library |
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* when the library is loaded, nor on a future call to |
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* shl_unload(). |
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* BIND_VERBOSE - Print verbose messages concerning possible |
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* unsatisfied symbols. |
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* |
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* hp9000s700/hp9000s800: |
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* BIND_RESTRICTED - Restrict symbols visible by the library to those |
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* present at library load time. |
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* DYNAMIC_PATH - Allow the loader to dynamically search for the |
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* library specified by the path argument. |
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*/ |
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|
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#if !defined DYNAMIC_PATH |
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# define DYNAMIC_PATH 0 |
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#endif |
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#if !defined BIND_RESTRICTED |
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# define BIND_RESTRICTED 0 |
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#endif |
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|
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#define LT_BIND_FLAGS (BIND_IMMEDIATE | BIND_NONFATAL | DYNAMIC_PATH) |
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|
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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 loader_data LT__UNUSED) |
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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 loader_data LT__UNUSED, const char *filename, |
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lt_dladvise advise LT__UNUSED) |
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{ |
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static shl_t self = (shl_t) 0; |
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lt_module module = shl_load (filename, LT_BIND_FLAGS, 0L); |
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|
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/* Since searching for a symbol against a NULL module handle will also |
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look in everything else that was already loaded and exported with |
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the -E compiler flag, we always cache a handle saved before any |
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modules are loaded. */ |
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if (!self) |
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{ |
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void *address; |
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shl_findsym (&self, "main", TYPE_UNDEFINED, &address); |
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} |
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|
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if (!filename) |
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{ |
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module = self; |
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} |
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else |
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{ |
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module = shl_load (filename, LT_BIND_FLAGS, 0L); |
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|
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if (!module) |
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{ |
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LT__SETERROR (CANNOT_OPEN); |
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} |
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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 loader_data LT__UNUSED, lt_module module) |
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{ |
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int errors = 0; |
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|
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if (module && (shl_unload ((shl_t) (module)) != 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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|
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return errors; |
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} |
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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 loader_data LT__UNUSED, lt_module module, const char *name) |
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{ |
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void *address = 0; |
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|
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/* sys_shl_open should never return a NULL module handle */ |
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if (module == (lt_module) 0) |
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{ |
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LT__SETERROR (INVALID_HANDLE); |
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} |
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else if (!shl_findsym((shl_t*) &module, name, TYPE_UNDEFINED, &address)) |
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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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|
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return address; |
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} |