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Change-Id: I6a4444e3c193dae437cd7929f4c39aba7b749efa
diff --git a/libfdcore/extensions.c b/libfdcore/extensions.c
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+/*********************************************************************************************************
+* Software License Agreement (BSD License) *
+* Author: Sebastien Decugis <sdecugis@freediameter.net> *
+* *
+* Copyright (c) 2013, WIDE Project and NICT *
+* All rights reserved. *
+* *
+* Redistribution and use of this software in source and binary forms, with or without modification, are *
+* permitted provided that the following conditions are met: *
+* *
+* * Redistributions of source code must retain the above *
+* copyright notice, this list of conditions and the *
+* following disclaimer. *
+* *
+* * Redistributions in binary form must reproduce the above *
+* copyright notice, this list of conditions and the *
+* following disclaimer in the documentation and/or other *
+* materials provided with the distribution. *
+* *
+* * Neither the name of the WIDE Project or NICT nor the *
+* names of its contributors may be used to endorse or *
+* promote products derived from this software without *
+* specific prior written permission of WIDE Project and *
+* NICT. *
+* *
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED *
+* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A *
+* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR *
+* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT *
+* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS *
+* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR *
+* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF *
+* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *
+*********************************************************************************************************/
+
+#include "fdcore-internal.h"
+
+#include <dlfcn.h> /* We may use libtool's <ltdl.h> later for better portability.... */
+#include <libgen.h> /* for "basename" */
+
+/* plugins management */
+
+/* List of extensions to load, from the configuration parsing */
+struct fd_ext_info {
+ struct fd_list chain; /* link in the list */
+ char *filename; /* extension filename. must be a dynamic library with fd_ext_init symbol. */
+ char *conffile; /* optional configuration file name for the extension */
+ void *handler; /* object returned by dlopen() */
+ const char **depends; /* names of the other extensions this one depends on (if provided) */
+ char *ext_name; /* points to the extension name, either inside depends, or basename(filename) */
+ int free_ext_name; /* must be freed if it was malloc'd */
+ void (*fini)(void); /* optional address of the fd_ext_fini callback */
+ char *proto_ver;
+ double gen_date;
+};
+
+/* list of extensions */
+static struct fd_list ext_list = FD_LIST_INITIALIZER(ext_list);
+
+/* Add new extension */
+int fd_ext_add( char * filename, char * conffile )
+{
+ struct fd_ext_info * new;
+
+ TRACE_ENTRY("%p %p", filename, conffile);
+
+ /* Check the filename is valid */
+ CHECK_PARAMS( filename );
+
+ /* Create a new object in the list */
+ CHECK_MALLOC( new = malloc( sizeof(struct fd_ext_info) ) );
+ memset(new, 0, sizeof(struct fd_ext_info));
+ fd_list_init(&new->chain, NULL);
+ new->filename = filename;
+ new->conffile = conffile;
+ fd_list_insert_before( &ext_list, &new->chain );
+ TRACE_DEBUG (FULL, "Extension %s added to the list.", filename);
+ return 0;
+}
+
+/* Dump the list */
+DECLARE_FD_DUMP_PROTOTYPE(fd_ext_dump)
+{
+ struct fd_list * li;
+ FD_DUMP_HANDLE_OFFSET();
+
+ if (FD_IS_LIST_EMPTY(&ext_list)) {
+ CHECK_MALLOC_DO( fd_dump_extend( FD_DUMP_STD_PARAMS, "-none-"), return NULL);
+ } else {
+ for (li = ext_list.next; li != &ext_list; li = li->next)
+ {
+ struct fd_ext_info * ext = (struct fd_ext_info *)li;
+ CHECK_MALLOC_DO( fd_dump_extend( FD_DUMP_STD_PARAMS, "'%s'[%s], %sloaded%s",
+ ext->filename,
+ ext->conffile?:"(no config file)",
+ ext->handler ? "" : "not ", (li->next == &ext_list) ? "":"\n"), return NULL);
+ }
+ }
+ return *buf;
+}
+
+/* Load the dependencies */
+static int load_dependencies(struct fd_ext_info *ext)
+{
+ TRACE_ENTRY( "%p", ext);
+ /* Attempt to resolve the dependency array */
+ ext->depends = dlsym( ext->handler, "fd_ext_depends");
+ if (!ext->depends) {
+ /* Duplicate the filename */
+ char * tmp = strdup(ext->filename);
+ ext->ext_name = strdup(basename(tmp));
+ free(tmp);
+ ext->free_ext_name = 1;
+ TRACE_DEBUG(FULL, "Old extension's [%s] API: missing dependencies (ignored)", ext->ext_name);
+ return 0;
+ }
+
+ ext->ext_name = (char *)ext->depends[0];
+ return 0;
+
+}
+
+/* Check the dependencies. The object must have been dlopened already. */
+static int check_dependencies(struct fd_ext_info * ext)
+{
+ int i = 1;
+ TRACE_DEBUG(FULL, "Checking dependencies for '%s'...", ext->ext_name);
+
+ while (ext->depends[i]) {
+ struct fd_list * li;
+ for (li = ext_list.next; li != &ext_list; li = li->next)
+ {
+ struct fd_ext_info * e = (struct fd_ext_info *)li;
+ if (!strcasecmp(e->ext_name, ext->depends[i])) {
+ /* the dependency was already loaded */
+ break;
+ }
+ }
+
+ if (li == &ext_list) {
+ /* the dependency was not found */
+ LOG_F("Error: extension [%s] depends on [%s] which was not loaded first. Please fix your configuration file.",
+ ext->ext_name, ext->depends[i]);
+ return ESRCH;
+ }
+
+ i++;
+ }
+
+ /* All dependencies resolved successfully */
+ return 0;
+}
+
+/* Load all extensions in the list */
+int fd_ext_load()
+{
+ int ret;
+ int (*fd_ext_init)(int, int, char *) = NULL;
+ int (*fd_ext_init2)(int, int, char *) = NULL;
+ struct fd_list * li;
+
+ TRACE_ENTRY();
+
+ /* Loop on all extensions */
+ for (li = ext_list.next; li != &ext_list; li = li->next)
+ {
+ struct fd_ext_info * ext = (struct fd_ext_info *)li;
+ LOG_D( "Loading : %s", ext->filename);
+
+ /* Load the extension */
+#ifndef DEBUG
+ ext->handler = dlopen(ext->filename, RTLD_LAZY | RTLD_GLOBAL);
+#else /* DEBUG */
+ /* We resolve symbols immediatly so it's easier to find problems in ABI */
+ ext->handler = dlopen(ext->filename, RTLD_NOW | RTLD_GLOBAL);
+#endif /* DEBUG */
+ if (ext->handler == NULL) {
+ /* An error occured */
+ LOG_F("Loading of extension %s failed: %s", ext->filename, dlerror());
+ ext->handler = dlopen(ext->filename, RTLD_LAZY | RTLD_GLOBAL);
+ if (ext->handler) {
+ if (!check_dependencies(ext)) {
+ LOG_F("In addition, not all declared dependencies are satisfied (Internal Error!)");
+ }
+ }
+ return EINVAL;
+ }
+
+ /* Resolve the entry point of the extension */
+ fd_ext_init = ( int (*) (int, int, char *) )dlsym( ext->handler, "fd_ext_init" );
+
+ if (fd_ext_init == NULL) {
+ /* An error occured */
+ TRACE_ERROR("Unable to resolve symbol 'fd_ext_init' for extension %s: %s", ext->filename, dlerror());
+ return EINVAL;
+ }
+
+
+ /* Resolve the exit point of the extension, which is optional for extensions */
+ ext->fini = ( void (*) (void) )dlsym( ext->handler, "fd_ext_fini" );
+
+ if (ext->fini == NULL) {
+ /* Not provided */
+ TRACE_DEBUG (FULL, "Extension [%s] has no fd_ext_fini function.", ext->filename);
+ } else {
+ /* Provided */
+ TRACE_DEBUG (FULL, "Extension [%s] fd_ext_fini has been resolved successfully.", ext->filename);
+ }
+
+ /* Now call the entry point to initialize the extension */
+ ret = (*fd_ext_init)( FD_PROJECT_VERSION_MAJOR, FD_PROJECT_VERSION_MINOR, ext->conffile );
+ if (ret != 0) {
+ /* The extension was unable to load cleanly */
+ TRACE_ERROR("Extension %s returned an error during initialization: %s", ext->filename, strerror(ret));
+ return ret;
+ }
+
+ /* Proceed to the next extension */
+ }
+
+ for( li = ext_list.next; li != &ext_list; li = li->next )
+ {
+ struct fd_ext_info * ext = (struct fd_ext_info *)li;
+ CHECK_FCT( load_dependencies(ext));
+ }
+
+
+ for( li = ext_list.next; li != &ext_list; li = li->next )
+ {
+ struct fd_ext_info * ext = (struct fd_ext_info *)li;
+
+ /* Check if declared dependencies are satisfied. */
+ CHECK_FCT( check_dependencies(ext) );
+
+ /* Loading methods init2 & parserules */
+ fd_ext_init2 = ( int (*) (int, int, char *) )dlsym( ext->handler, "fd_ext_init2" );
+
+ if (fd_ext_init2 == NULL) {
+ /* Old extensions do not define fd_ext_init2 */
+ LOG_N("Unable to resolve symbol 'fd_ext_init2' for extension %s: ", ext->filename);
+ }
+ else {
+ ret = (*fd_ext_init2)( FD_PROJECT_VERSION_MAJOR, FD_PROJECT_VERSION_MINOR, ext->conffile );
+ if (ret != 0) {
+ /* The extension was unable to load cleanly */
+ TRACE_ERROR("Extension %s returned an error during parse local rules: %s", ext->filename, strerror(ret));
+ return ret;
+ }
+ }
+ }
+
+ LOG_N("All extensions loaded.");
+
+ /* We have finished. */
+ return 0;
+}
+
+/* Now unload the extensions and free the memory */
+int fd_ext_term( void )
+{
+ TRACE_ENTRY();
+
+ /* Loop on all extensions, in FIFO order */
+ while (!FD_IS_LIST_EMPTY(&ext_list))
+ {
+ struct fd_list * li = ext_list.next;
+ struct fd_ext_info * ext = (struct fd_ext_info *)li;
+
+ /* Unlink this element from the list */
+ fd_list_unlink(li);
+
+ /* Call the exit point of the extension, if it was resolved */
+ if (ext->fini != NULL) {
+ TRACE_DEBUG (FULL, "Calling [%s]->fd_ext_fini function.", ext->ext_name ?: ext->filename);
+ (*ext->fini)();
+ }
+
+#ifndef SKIP_DLCLOSE
+ /* Now unload the extension */
+ if (ext->handler) {
+ TRACE_DEBUG (FULL, "Unloading %s", ext->ext_name ?: ext->filename);
+ if ( dlclose(ext->handler) != 0 ) {
+ TRACE_DEBUG (INFO, "Unloading [%s] failed : %s", ext->ext_name ?: ext->filename, dlerror());
+ }
+ }
+#endif /* SKIP_DLCLOSE */
+
+ /* Free the object and continue */
+ if (ext->free_ext_name)
+ free(ext->ext_name);
+ free(ext->filename);
+ free(ext->conffile);
+ free(ext);
+ }
+
+ /* We always return 0 since we would not handle an error anyway... */
+ return 0;
+}
+