From 72a40536f90aca5bebb714a2d02af4cb2bc67fdd Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Mon, 24 Nov 2008 20:17:57 +0100 Subject: ModuleManager angefangen; libltdl zum Projekt hinzugefuegt --- libltdl/lt_dlloader.c | 210 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 210 insertions(+) create mode 100644 libltdl/lt_dlloader.c (limited to 'libltdl/lt_dlloader.c') diff --git a/libltdl/lt_dlloader.c b/libltdl/lt_dlloader.c new file mode 100644 index 0000000..4e66a6c --- /dev/null +++ b/libltdl/lt_dlloader.c @@ -0,0 +1,210 @@ +/* lt_dlloader.c -- dynamic library loader interface + + Copyright (C) 2004, 2007, 2008 Free Software Foundation, Inc. + Written by Gary V. Vaughan, 2004 + + 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" + +#define RETURN_SUCCESS 0 +#define RETURN_FAILURE 1 + +static void * loader_callback (SList *item, void *userdata); + +/* A list of all the dlloaders we know about, each stored as a boxed + SList item: */ +static SList *loaders = 0; + + +/* Return NULL, unless the loader in this ITEM has a matching name, + in which case we return the matching item so that its address is + passed back out (for possible freeing) by slist_remove. */ +static void * +loader_callback (SList *item, void *userdata) +{ + const lt_dlvtable *vtable = (const lt_dlvtable *) item->userdata; + const char * name = (const char *) userdata; + + assert (vtable); + + return streq (vtable->name, name) ? (void *) item : NULL; +} + + +/* Hook VTABLE into our global LOADERS list according to its own + PRIORITY field value. */ +int +lt_dlloader_add (const lt_dlvtable *vtable) +{ + SList *item; + + if ((vtable == 0) /* diagnose invalid vtable fields */ + || (vtable->module_open == 0) + || (vtable->module_close == 0) + || (vtable->find_sym == 0) + || ((vtable->priority != LT_DLLOADER_PREPEND) && + (vtable->priority != LT_DLLOADER_APPEND))) + { + LT__SETERROR (INVALID_LOADER); + return RETURN_FAILURE; + } + + item = slist_box (vtable); + if (!item) + { + (*lt__alloc_die) (); + + /* Let the caller know something went wrong if lt__alloc_die + doesn't abort. */ + return RETURN_FAILURE; + } + + if (vtable->priority == LT_DLLOADER_PREPEND) + { + loaders = slist_cons (item, loaders); + } + else + { + assert (vtable->priority == LT_DLLOADER_APPEND); + loaders = slist_concat (loaders, item); + } + + return RETURN_SUCCESS; +} + +#ifdef LT_DEBUG_LOADERS +static void * +loader_dump_callback (SList *item, void *userdata) +{ + const lt_dlvtable *vtable = (const lt_dlvtable *) item->userdata; + fprintf (stderr, ", %s", (vtable && vtable->name) ? vtable->name : "(null)"); + return 0; +} + +void +lt_dlloader_dump (void) +{ + fprintf (stderr, "loaders: "); + if (!loaders) + { + fprintf (stderr, "(empty)"); + } + else + { + const lt_dlvtable *head = (const lt_dlvtable *) loaders->userdata; + fprintf (stderr, "%s", (head && head->name) ? head->name : "(null)"); + if (slist_tail (loaders)) + slist_foreach (slist_tail (loaders), loader_dump_callback, NULL); + } + fprintf (stderr, "\n"); +} +#endif + +/* An iterator for the global loader list: if LOADER is NULL, then + return the first element, otherwise the following element. */ +lt_dlloader +lt_dlloader_next (lt_dlloader loader) +{ + SList *item = (SList *) loader; + return (lt_dlloader) (item ? item->next : loaders); +} + + +/* Non-destructive unboxing of a loader. */ +const lt_dlvtable * +lt_dlloader_get (lt_dlloader loader) +{ + return (const lt_dlvtable *) (loader ? ((SList *) loader)->userdata : NULL); +} + + +/* Return the contents of the first item in the global loader list + with a matching NAME after removing it from that list. If there + was no match, return NULL; if there is an error, return NULL and + set an error for lt_dlerror; do not set an error if only resident + modules need this loader; in either case, the loader list is not + changed if NULL is returned. */ +lt_dlvtable * +lt_dlloader_remove (char *name) +{ + const lt_dlvtable * vtable = lt_dlloader_find (name); + static const char id_string[] = "lt_dlloader_remove"; + lt_dlinterface_id iface; + lt_dlhandle handle = 0; + int in_use = 0; + int in_use_by_resident = 0; + + if (!vtable) + { + LT__SETERROR (INVALID_LOADER); + return 0; + } + + /* Fail if there are any open modules which use this loader. */ + iface = lt_dlinterface_register (id_string, NULL); + while ((handle = lt_dlhandle_iterate (iface, handle))) + { + lt_dlhandle cur = handle; + if (cur->vtable == vtable) + { + in_use = 1; + if (lt_dlisresident (handle)) + in_use_by_resident = 1; + } + } + lt_dlinterface_free (iface); + if (in_use) + { + if (!in_use_by_resident) + LT__SETERROR (REMOVE_LOADER); + return 0; + } + + /* Call the loader finalisation function. */ + if (vtable && vtable->dlloader_exit) + { + if ((*vtable->dlloader_exit) (vtable->dlloader_data) != 0) + { + /* If there is an exit function, and it returns non-zero + then it must set an error, and we will not remove it + from the list. */ + return 0; + } + } + + /* If we got this far, remove the loader from our global list. */ + return (lt_dlvtable *) + slist_unbox ((SList *) slist_remove (&loaders, loader_callback, name)); +} + + +const lt_dlvtable * +lt_dlloader_find (char *name) +{ + return lt_dlloader_get (slist_find (loaders, loader_callback, name)); +} -- cgit v1.2.3