+++ /dev/null
-/* loader-preopen.c -- emulate dynamic linking using preloaded_symbols
-
- Copyright (C) 1998, 1999, 2000, 2004, 2006,
- 2007, 2008 Free Software Foundation, Inc.
- Written by Thomas Tanner, 1998
-
- NOTE: The canonical source of this file is maintained with the
- GNU Libtool package. Report bugs to bug-libtool@gnu.org.
-
-GNU Libltdl is free software; you can redistribute it and/or
-modify it under the terms of the GNU Lesser General Public
-License as published by the Free Software Foundation; either
-version 2 of the License, or (at your option) any later version.
-
-As a special exception to the GNU Lesser General Public License,
-if you distribute this file as part of a program or library that
-is built using GNU Libtool, you may include this file under the
-same distribution terms that you use for the rest of that program.
-
-GNU Libltdl is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU Lesser General Public License for more details.
-
-You should have received a copy of the GNU Lesser General Public
-License along with GNU Libltdl; see the file COPYING.LIB. If not, a
-copy can be downloaded from http://www.gnu.org/licenses/lgpl.html,
-or obtained by writing to the Free Software Foundation, Inc.,
-51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
-*/
-
-#include "lt__private.h"
-#include "lt_dlloader.h"
-
-/* Use the preprocessor to rename non-static symbols to avoid namespace
- collisions when the loader code is statically linked into libltdl.
- Use the "<module_name>_LTX_" prefix so that the symbol addresses can
- be fetched from the preloaded symbol list by lt_dlsym(): */
-#define get_vtable preopen_LTX_get_vtable
-
-LT_BEGIN_C_DECLS
-LT_SCOPE lt_dlvtable *get_vtable (lt_user_data loader_data);
-LT_END_C_DECLS
-
-
-/* Boilerplate code to set up the vtable for hooking this loader into
- libltdl's loader list: */
-static int vl_init (lt_user_data loader_data);
-static int vl_exit (lt_user_data loader_data);
-static lt_module vm_open (lt_user_data loader_data, const char *filename,
- lt_dladvise advise);
-static int vm_close (lt_user_data loader_data, lt_module module);
-static void * vm_sym (lt_user_data loader_data, lt_module module,
- const char *symbolname);
-
-static lt_dlvtable *vtable = 0;
-
-/* Return the vtable for this loader, only the name and sym_prefix
- attributes (plus the virtual function implementations, obviously)
- change between loaders. */
-lt_dlvtable *
-get_vtable (lt_user_data loader_data)
-{
- if (!vtable)
- {
- vtable = (lt_dlvtable *) lt__zalloc (sizeof *vtable);
- }
-
- if (vtable && !vtable->name)
- {
- vtable->name = "lt_preopen";
- vtable->sym_prefix = 0;
- vtable->module_open = vm_open;
- vtable->module_close = vm_close;
- vtable->find_sym = vm_sym;
- vtable->dlloader_init = vl_init;
- vtable->dlloader_exit = vl_exit;
- vtable->dlloader_data = loader_data;
- vtable->priority = LT_DLLOADER_PREPEND;
- }
-
- if (vtable && (vtable->dlloader_data != loader_data))
- {
- LT__SETERROR (INIT_LOADER);
- return 0;
- }
-
- return vtable;
-}
-
-
-
-/* --- IMPLEMENTATION --- */
-
-
-/* Wrapper type to chain together symbol lists of various origins. */
-typedef struct symlist_chain
-{
- struct symlist_chain *next;
- const lt_dlsymlist *symlist;
-} symlist_chain;
-
-
-static int add_symlist (const lt_dlsymlist *symlist);
-static int free_symlists (void);
-
-/* The start of the symbol lists chain. */
-static symlist_chain *preloaded_symlists = 0;
-
-/* A symbol list preloaded before lt_init() was called. */
-static const lt_dlsymlist *default_preloaded_symbols = 0;
-
-
-/* A function called through the vtable to initialise this loader. */
-static int
-vl_init (lt_user_data LT__UNUSED loader_data)
-{
- int errors = 0;
-
- preloaded_symlists = 0;
- if (default_preloaded_symbols)
- {
- errors = lt_dlpreload (default_preloaded_symbols);
- }
-
- return errors;
-}
-
-
-/* A function called through the vtable when this loader is no
- longer needed by the application. */
-static int
-vl_exit (lt_user_data LT__UNUSED loader_data)
-{
- vtable = NULL;
- free_symlists ();
- return 0;
-}
-
-
-/* A function called through the vtable to open a module with this
- loader. Returns an opaque representation of the newly opened
- module for processing with this loader's other vtable functions. */
-static lt_module
-vm_open (lt_user_data LT__UNUSED loader_data, const char *filename,
- lt_dladvise LT__UNUSED advise)
-{
- symlist_chain *lists;
- lt_module module = 0;
-
- if (!preloaded_symlists)
- {
- LT__SETERROR (NO_SYMBOLS);
- goto done;
- }
-
- /* Can't use NULL as the reflective symbol header, as NULL is
- used to mark the end of the entire symbol list. Self-dlpreopened
- symbols follow this magic number, chosen to be an unlikely
- clash with a real module name. */
- if (!filename)
- {
- filename = "@PROGRAM@";
- }
-
- for (lists = preloaded_symlists; lists; lists = lists->next)
- {
- const lt_dlsymlist *symbol;
- for (symbol= lists->symlist; symbol->name; ++symbol)
- {
- if (!symbol->address && streq (symbol->name, filename))
- {
- /* If the next symbol's name and address is 0, it means
- the module just contains the originator and no symbols.
- In this case we pretend that we never saw the module and
- hope that some other loader will be able to load the module
- and have access to its symbols */
- const lt_dlsymlist *next_symbol = symbol +1;
- if (next_symbol->address && next_symbol->name)
- {
- module = (lt_module) lists->symlist;
- goto done;
- }
- }
- }
- }
-
- LT__SETERROR (FILE_NOT_FOUND);
-
- done:
- return module;
-}
-
-
-/* A function called through the vtable when a particular module
- should be unloaded. */
-static int
-vm_close (lt_user_data LT__UNUSED loader_data, lt_module LT__UNUSED module)
-{
- /* Just to silence gcc -Wall */
- module = 0;
- return 0;
-}
-
-
-/* A function called through the vtable to get the address of
- a symbol loaded from a particular module. */
-static void *
-vm_sym (lt_user_data LT__UNUSED loader_data, lt_module module, const char *name)
-{
- lt_dlsymlist *symbol = (lt_dlsymlist*) module;
-
- symbol +=2; /* Skip header (originator then libname). */
-
- while (symbol->name)
- {
- if (streq (symbol->name, name))
- {
- return symbol->address;
- }
-
- ++symbol;
- }
-
- LT__SETERROR (SYMBOL_NOT_FOUND);
-
- return 0;
-}
-
-
-
-/* --- HELPER FUNCTIONS --- */
-
-
-/* The symbol lists themselves are not allocated from the heap, but
- we can unhook them and free up the chain of links between them. */
-static int
-free_symlists (void)
-{
- symlist_chain *lists;
-
- lists = preloaded_symlists;
- while (lists)
- {
- symlist_chain *next = lists->next;
- FREE (lists);
- lists = next;
- }
- preloaded_symlists = 0;
-
- return 0;
-}
-
-/* Add a new symbol list to the global chain. */
-static int
-add_symlist (const lt_dlsymlist *symlist)
-{
- symlist_chain *lists;
- int errors = 0;
-
- /* Search for duplicate entries: */
- for (lists = preloaded_symlists;
- lists && lists->symlist != symlist; lists = lists->next)
- /*NOWORK*/;
-
- /* Don't add the same list twice: */
- if (!lists)
- {
- symlist_chain *tmp = (symlist_chain *) lt__zalloc (sizeof *tmp);
-
- if (tmp)
- {
- tmp->symlist = symlist;
- tmp->next = preloaded_symlists;
- preloaded_symlists = tmp;
- }
- else
- {
- ++errors;
- }
- }
-
- return errors;
-}
-
-
-
-/* --- PRELOADING API CALL IMPLEMENTATIONS --- */
-
-
-/* Save a default symbol list for later. */
-int
-lt_dlpreload_default (const lt_dlsymlist *preloaded)
-{
- default_preloaded_symbols = preloaded;
- return 0;
-}
-
-
-/* Add a symbol list to the global chain, or with a NULL argument,
- revert to just the default list. */
-int
-lt_dlpreload (const lt_dlsymlist *preloaded)
-{
- int errors = 0;
-
- if (preloaded)
- {
- errors = add_symlist (preloaded);
- }
- else
- {
- free_symlists();
-
- if (default_preloaded_symbols)
- {
- errors = lt_dlpreload (default_preloaded_symbols);
- }
- }
-
- return errors;
-}
-
-
-/* Open all the preloaded modules from the named originator, executing
- a callback for each one. If ORIGINATOR is NULL, then call FUNC for
- each preloaded module from the program itself. */
-int
-lt_dlpreload_open (const char *originator, lt_dlpreload_callback_func *func)
-{
- symlist_chain *list;
- int errors = 0;
- int found = 0;
-
- /* For each symlist in the chain... */
- for (list = preloaded_symlists; list; list = list->next)
- {
- /* ...that was preloaded by the requesting ORIGINATOR... */
- if ((originator && streq (list->symlist->name, originator))
- || (!originator && streq (list->symlist->name, "@PROGRAM@")))
- {
- const lt_dlsymlist *symbol;
- unsigned int idx = 0;
-
- ++found;
-
- /* ...load the symbols per source compilation unit:
- (we preincrement the index to skip over the originator entry) */
- while ((symbol = &list->symlist[++idx])->name != 0)
- {
- if ((symbol->address == 0)
- && (strneq (symbol->name, "@PROGRAM@")))
- {
- lt_dlhandle handle = lt_dlopen (symbol->name);
- if (handle == 0)
- {
- ++errors;
- }
- else
- {
- errors += (*func) (handle);
- }
- }
- }
- }
- }
-
- if (!found)
- {
- LT__SETERROR(CANNOT_OPEN);
- ++errors;
- }
-
- return errors;
-}
HCoop / hcoop / debian / courier-authlib.git / blobdiff