tm: disable 6xx or failover on a per message basis

Added support for disabling 6xx special handling and dns failover
on a per transaction basis:

- t_set_disable_6xx(0|1): disable(1)/enable(0) 6xx rfc special handling.
- t_set_disable_failover(0|1): disable/enable dns failover.

They both work either on the current transaction (if it was
already created) or on the next transaction that will be created
(e.g. t_set_disable_6xx(1); t_relay()  works).

modules/tm/h_table.h

@@ -273,6 +273,9 @@ struct totag_elem {
 	/* don't generate automatically an ACK for local transaction */
 #	define T_NO_AUTO_ACK	(1<<7)
 #endif
+
+#define T_DISABLE_6xx (1<<8) /* treat 6xx as a normal reply */
+#define T_DISABLE_FAILOVER (1<<9) /* don't perform dns failover */
 #define T_DONT_FORK   (T_CANCELED|T_6xx)
 
 /* unsigned short should be enough for a retr. timer: max. 65535 ticks =>

modules/tm/t_funcs.c

@@ -90,7 +90,8 @@ static int     contacts_avp_index = 0;
 
 int tm_error = 0; /* delayed tm error */
 
-struct msgid_var user_auto_inv_100;
+struct msgid_var user_cell_set_flags;   /* extra cell->flags to be set */
+struct msgid_var user_cell_reset_flags; /* extra cell->flags to be reset */
 
 /* ----------------------------------------------------- */
 int send_pr_buffer(	struct retr_buf *rb, void *buf, int len

modules/tm/t_funcs.h

@@ -74,7 +74,8 @@ struct entry;
 struct cell;
 
 extern int tm_error; /* delayed tm error */
-extern struct msgid_var user_auto_inv_100;
+extern struct msgid_var user_cell_set_flags;
+extern struct msgid_var user_cell_reset_flags;
 
 extern int fr_inv_timer_avp_type;
 extern int_str fr_inv_timer_avp;

modules/tm/t_fwd.c

@@ -649,8 +649,9 @@ int add_uac_dns_fallback(struct cell *t, struct sip_msg* msg,
 	int ret;
 	
 	ret=-1;
-	if (cfg_get(core, core_cfg, use_dns_failover) && 
-			!((t->flags & T_DONT_FORK) || uac_dont_fork(old_uac)) &&
+	if (cfg_get(core, core_cfg, use_dns_failover) &&
+			!((t->flags & (T_DONT_FORK|T_DISABLE_FAILOVER)) ||
+				uac_dont_fork(old_uac)) &&
 			dns_srv_handle_next(&old_uac->dns_h, 0)){
 			if (lock_replies){
 				/* use reply lock to guarantee nobody is adding a branch

modules/tm/t_lookup.c

@@ -1243,7 +1243,6 @@ static inline void init_new_t(struct cell *new_cell, struct sip_msg *p_msg)
 	struct sip_msg *shm_msg;
 	unsigned int timeout; /* avp timeout gets stored here (in s) */
 	ticks_t lifetime;
-	int v;
 
 	shm_msg=new_cell->uas.request;
 	new_cell->from.s=shm_msg->from->name.s;
@@ -1259,13 +1258,17 @@ static inline void init_new_t(struct cell *new_cell, struct sip_msg *p_msg)
 
 	new_cell->method=new_cell->uas.request->first_line.u.request.method;
 	if (p_msg->REQ_METHOD==METHOD_INVITE){
-		new_cell->flags |= T_IS_INVITE_FLAG;
-		if (unlikely(v=get_msgid_val(user_auto_inv_100, p_msg->id, int)))
-			/* 1 = set, -1 = reset */
-			new_cell->flags|=T_AUTO_INV_100 & (!(v+1)-1);
-		else
-			new_cell->flags|=T_AUTO_INV_100 &
+		/* set flags */
+		new_cell->flags |= T_IS_INVITE_FLAG |
+			get_msgid_val(user_cell_set_flags, p_msg->id, int);
+		new_cell->flags|=T_AUTO_INV_100 &
 					(!cfg_get(tm, tm_cfg, tm_auto_inv_100) -1);
+		new_cell->flags|=T_DISABLE_6xx &
+					(!cfg_get(tm, tm_cfg, disable_6xx) -1);
+		/* reset flags */
+		new_cell->flags &=
+			(~ get_msgid_val(user_cell_reset_flags, p_msg->id, int));
+		
 		lifetime=(ticks_t)get_msgid_val(user_inv_max_lifetime,
 												p_msg->id, int);
 		if (likely(lifetime==0))

modules/tm/t_reply.c

@@ -1086,10 +1086,10 @@ static enum rps t_should_relay_response( struct cell *Trans , int new_code,
 		if (picked_branch==-2) { /* branches open yet */
 			*should_store=1;
 			*should_relay=-1;
-			if (new_code>=600 && new_code<=699 &&
-					!cfg_get(tm, tm_cfg, disable_6xx)){
-				if (!(Trans->flags & T_6xx)){
-					/* cancel only the first time we get a 6xx */
+			if (new_code>=600 && new_code<=699){
+				if (!(Trans->flags & (T_6xx | T_DISABLE_6xx))){
+					/* cancel only the first time we get a 6xx and only
+					  if the 6xx handling is not disabled */
 					prepare_to_cancel(Trans, cancel_bitmap, 0);
 					Trans->flags|=T_6xx;
 				}

modules/tm/tm.c

@@ -228,6 +228,8 @@ static int w_t_reset_retr(struct sip_msg* msg, char* foo, char* bar);
 static int w_t_set_max_lifetime(struct sip_msg* msg, char* inv, char* noninv);
 static int w_t_reset_max_lifetime(struct sip_msg* msg, char* foo, char* bar);
 static int t_set_auto_inv_100(struct sip_msg* msg, char* on_off, char* foo);
+static int t_set_disable_6xx(struct sip_msg* msg, char* on_off, char* foo);
+static int t_set_disable_failover(struct sip_msg* msg, char* on_off, char* f);
 static int t_branch_timeout(struct sip_msg* msg, char*, char*);
 static int t_branch_replied(struct sip_msg* msg, char*, char*);
 static int t_any_timeout(struct sip_msg* msg, char*, char*);
@@ -361,6 +363,10 @@ static cmd_export_t cmds[]={
 			REQUEST_ROUTE|ONREPLY_ROUTE|FAILURE_ROUTE|BRANCH_ROUTE },
 	{"t_set_auto_inv_100", t_set_auto_inv_100,       1, fixup_var_int_1,
 													  REQUEST_ROUTE},
+	{"t_set_disable_6xx", t_set_disable_6xx,         1, fixup_var_int_1,
+			REQUEST_ROUTE|ONREPLY_ROUTE|FAILURE_ROUTE|BRANCH_ROUTE },
+	{"t_set_disable_failover", t_set_disable_failover, 1, fixup_var_int_1,
+			REQUEST_ROUTE|ONREPLY_ROUTE|FAILURE_ROUTE|BRANCH_ROUTE },
 	{"t_branch_timeout",  t_branch_timeout,         0, 0,  FAILURE_ROUTE},
 	{"t_branch_replied",  t_branch_replied,         0, 0,  FAILURE_ROUTE},
 	{"t_any_timeout",     t_any_timeout,            0, 0, 
@@ -1525,31 +1531,62 @@ int w_t_reset_max_lifetime(struct sip_msg* msg, char* foo, char* bar)
 	return t_reset_max_lifetime();
 }
 
+
+
+/* helper macro, builds a function for setting a cell flag from the script.
+   e.g. T_SET_FLAG_GEN_FUNC(t_set_foo, T_FOO) =>
+   static int t_set_foo(struct sip_msg* msg, char*, char* )
+   that will expect fparam as first param and will set or reset T_FOO
+   in the current or next to be created transaction. */
+#define T_SET_FLAG_GEN_FUNC(fname, T_FLAG_NAME) \
+static int fname(struct sip_msg* msg, char* p1, char* p2) \
+{ \
+	int state; \
+	struct cell* t; \
+	unsigned int set_flags; \
+	unsigned int reset_flags; \
+	 \
+	if (get_int_fparam(&state, msg, (fparam_t*)p1) < 0) return -1; \
+	t=get_t(); \
+	/* in REPLY_ROUTE and FAILURE_ROUTE T will be set to current transaction; \
+	 * in REQUEST_ROUTE T will be set only if the transaction was already  \
+	 * created; if not -> use the static variables */ \
+	if (!t || t==T_UNDEFINED ){ \
+		set_flags=get_msgid_val(user_cell_set_flags, msg->id, int); \
+		reset_flags=get_msgid_val(user_cell_reset_flags, msg->id, int); \
+		if (state){ \
+			/* set */ \
+			set_flags|= T_FLAG_NAME; \
+			reset_flags&=~T_FLAG_NAME; \
+		}else{ \
+			/* reset */ \
+			set_flags&=~T_FLAG_NAME; \
+			reset_flags|=T_FLAG_NAME; \
+		} \
+		set_msgid_val(user_cell_set_flags, msg->id, int, set_flags); \
+		set_msgid_val(user_cell_reset_flags, msg->id, int, reset_flags); \
+	}else{ \
+		if (state) \
+			t->flags|=T_FLAG_NAME; \
+		else \
+			t->flags&=~T_FLAG_NAME; \
+	} \
+	return 1; \
+}
+
+
+
 /* set automatically sending 100 replies on/off for the current or
  * next to be created transaction */
-static int t_set_auto_inv_100(struct sip_msg* msg, char* p1, char* p2)
-{
-	int state;
-	struct cell* t;
-	
-	if (get_int_fparam(&state, msg, (fparam_t*)p1) < 0) return -1;
-	t=get_t();
-	/* in REPLY_ROUTE and FAILURE_ROUTE T will be set to current transaction;
-	 * in REQUEST_ROUTE T will be set only if the transaction was already
-	 * created; if not -> use the static variables */
-	if (!t || t==T_UNDEFINED ){
-		if (state)
-			set_msgid_val(user_auto_inv_100, msg->id, int, 1); /* set */
-		else
-			set_msgid_val(user_auto_inv_100, msg->id, int, -1); /* reset */
-	}else{
-		if (state)
-			t->flags|=T_AUTO_INV_100;
-		else
-			t->flags&=~T_AUTO_INV_100;
-	}
-	return 1;
-}
+T_SET_FLAG_GEN_FUNC(t_set_auto_inv_100, T_AUTO_INV_100)
+
+
+/* set 6xx handling for the current or next to be created transaction */
+T_SET_FLAG_GEN_FUNC(t_set_disable_6xx, T_DISABLE_6xx)
+
+
+/* disable dns failover for the current transaction */
+T_SET_FLAG_GEN_FUNC(t_set_disable_failover, T_DISABLE_FAILOVER)