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Change-Id: I6a4444e3c193dae437cd7929f4c39aba7b749efa
diff --git a/libfdproto/dispatch.c b/libfdproto/dispatch.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 "fdproto-internal.h"
+
+/* The dispatch module in the library is quite simple: callbacks are saved in a global list
+ * in no particular order. In addition, they are also linked from the dictionary objects they
+ * refer to. */
+
+/* Protection for the lists managed in this module. */
+pthread_rwlock_t fd_disp_lock = PTHREAD_RWLOCK_INITIALIZER;
+
+/* List of all registered handlers -- useful if we want to cleanup properly at some point... */
+static struct fd_list all_handlers = FD_LIST_INITIALIZER( all_handlers );
+
+/* List of handlers registered for DISP_HOW_ANY. Other handlers are stored in the dictionary */
+static struct fd_list any_handlers = FD_LIST_INITIALIZER( any_handlers );
+
+/* The structure to store a callback */
+struct disp_hdl {
+	int		 eyec;	/* Eye catcher, DISP_EYEC */
+	struct fd_list	 all;	/* link in the all_handlers list */
+	struct fd_list	 parent;/* link in dictionary cb_list or in any_handlers */
+	enum disp_how	 how;	/* Copy of registration parameter */
+	struct disp_when when;	/* Copy of registration parameter */
+	int		(*cb)( struct msg **, struct avp *, struct session *, void *, enum disp_action *);	/* The callback itself */
+	void            *opaque; /* opaque data passed back to the callback */
+};
+
+#define DISP_EYEC	0xD15241C1
+#define VALIDATE_HDL( _hdl ) \
+	( ( ( _hdl ) != NULL ) && ( ((struct disp_hdl *)( _hdl ))->eyec == DISP_EYEC ) )
+
+/**************************************************************************************/
+
+/* Call CBs from a given list (any_handlers if cb_list is NULL) -- must have locked fd_disp_lock before */
+int fd_disp_call_cb_int( struct fd_list * cb_list, struct msg ** msg, struct avp *avp, struct session *sess, enum disp_action *action, 
+			struct dict_object * obj_app, struct dict_object * obj_cmd, struct dict_object * obj_avp, struct dict_object * obj_enu,
+			char ** drop_reason, struct msg ** drop_msg)
+{
+	struct fd_list * senti, *li;
+	int r;
+	TRACE_ENTRY("%p %p %p %p %p %p %p %p %p", cb_list, msg, avp, sess, action, obj_app, obj_cmd, obj_avp, obj_enu);
+	CHECK_PARAMS(msg && action);
+	
+	senti = cb_list;
+	if (!senti)
+		senti = &any_handlers;
+	
+	for (li = senti->next; li != senti; li = li->next) {
+		struct disp_hdl * hdl = (struct disp_hdl *)(li->o);
+		
+		TRACE_DEBUG(ANNOYING, "when: %p %p %p %p", hdl->when.app, hdl->when.command, hdl->when.avp, hdl->when.value);
+		
+		/* Check this handler matches this message / avp */
+		if (hdl->when.app     && (hdl->when.app     != obj_app))
+			continue;
+		if (hdl->when.command && (hdl->when.command != obj_cmd))
+			continue;
+		if (hdl->when.avp     && (hdl->when.avp     != obj_avp))
+			continue;
+		if (hdl->when.value   && (hdl->when.value   != obj_enu))
+			continue;
+		
+		/* We have a match, the cb must be called. */
+		CHECK_FCT_DO( (r = (*hdl->cb)(msg, avp, sess, hdl->opaque, action)),
+			{
+				*drop_reason = "Internal error: a DISPATCH callback returned an error";
+				*drop_msg = *msg;
+				*msg = NULL;
+			}
+		 );
+		
+		if (*action != DISP_ACT_CONT)
+			break;
+		
+		if ( *msg  == NULL )
+			break;
+	}
+	
+	/* We're done on this list */
+	return 0;
+}
+
+/**************************************************************************************/
+
+/* Create a new handler and link it */
+int fd_disp_register ( int (*cb)( struct msg **, struct avp *, struct session *, void *, enum disp_action *), 
+			enum disp_how how, struct disp_when * when, void * opaque, struct disp_hdl ** handle )
+{
+	struct fd_list * cb_list = NULL;
+	struct disp_hdl * new;
+	struct dict_object * type_enum = NULL, * type_avp;
+	struct dictionary  * dict = NULL;
+	
+	TRACE_ENTRY("%p %d %p %p", cb, how, when, handle);
+	CHECK_PARAMS( cb && ( (how == DISP_HOW_ANY) || when ));
+	
+	switch (how) {
+		case DISP_HOW_ANY:
+			cb_list = &any_handlers;
+			break;
+		
+		case DISP_HOW_APPID:
+			CHECK_FCT( fd_dict_disp_cb(DICT_APPLICATION, when->app, &cb_list) );
+			break;
+		
+		case DISP_HOW_CC:
+			CHECK_FCT( fd_dict_disp_cb(DICT_COMMAND, when->command, &cb_list) );
+			break;
+		
+		case DISP_HOW_AVP_ENUMVAL:
+			CHECK_FCT( fd_dict_disp_cb(DICT_ENUMVAL, when->value, &cb_list) ); /* cb_list is then overwritten */
+			CHECK_FCT( fd_dict_getdict(when->value, &dict) );
+			CHECK_FCT( fd_dict_search(dict, DICT_TYPE, TYPE_OF_ENUMVAL, when->value, &type_enum, EINVAL) );
+		case DISP_HOW_AVP:
+			CHECK_FCT( fd_dict_disp_cb(DICT_AVP, when->avp, &cb_list) );
+			if (dict) {
+				CHECK_FCT( fd_dict_search(dict, DICT_TYPE, TYPE_OF_AVP, when->avp, &type_avp, EINVAL) );
+				if (type_enum) {
+					CHECK_PARAMS( type_enum == type_avp );
+				}
+			}
+			break;
+		
+		default:
+			CHECK_PARAMS(how = 0);
+	}
+	/* We might further check optional fields, but we trust the caller ^^ */
+	
+	/* Create the new handler */
+	CHECK_MALLOC( new = malloc( sizeof(struct disp_hdl) ) );
+	memset(new, 0, sizeof(struct disp_hdl));
+	new->eyec = DISP_EYEC;
+	fd_list_init(&new->all, new);
+	fd_list_init(&new->parent, new);
+	new->how = how;
+	switch (how) {
+		case DISP_HOW_ANY:
+			/* there is no "when" in that case */
+			break;
+		case DISP_HOW_AVP_ENUMVAL:
+			new->when.value   = when->value;
+		case DISP_HOW_AVP:
+			new->when.avp     = when->avp;
+		case DISP_HOW_CC:
+			new->when.command = when->command;
+		case DISP_HOW_APPID:
+			new->when.app     = when->app;
+	}
+	new->cb = cb;
+	new->opaque = opaque;
+	
+	/* Now, link this new element in the appropriate lists */
+	CHECK_POSIX( pthread_rwlock_wrlock(&fd_disp_lock) );
+	fd_list_insert_before(&all_handlers, &new->all);
+	fd_list_insert_before(cb_list, &new->parent);
+	CHECK_POSIX( pthread_rwlock_unlock(&fd_disp_lock) );
+	
+	/* We're done */
+	if (handle)
+		*handle = new;
+	
+	return 0;
+}
+
+/* Delete a handler */
+int fd_disp_unregister ( struct disp_hdl ** handle, void ** opaque )
+{
+	struct disp_hdl * del;
+	TRACE_ENTRY("%p", handle);
+	CHECK_PARAMS( handle && VALIDATE_HDL(*handle) );
+	del = *handle;
+	*handle = NULL;
+	
+	CHECK_POSIX( pthread_rwlock_wrlock(&fd_disp_lock) );
+	fd_list_unlink(&del->all);
+	fd_list_unlink(&del->parent);
+	CHECK_POSIX( pthread_rwlock_unlock(&fd_disp_lock) );
+	
+	if (opaque)
+		*opaque = del->opaque;
+	
+	free(del);
+	return 0;
+}
+
+/* Delete all handlers */
+void fd_disp_unregister_all ( void )
+{
+	TRACE_ENTRY("");
+	while (!FD_IS_LIST_EMPTY(&all_handlers)) {
+		CHECK_FCT_DO( fd_disp_unregister((void *)&(all_handlers.next->o), NULL), /* continue */ );
+	}
+	return;
+}