Workaround for ticket #50: added API to lock/bind transaction, dialog, and regc to a specific transport/listener

git-svn-id: http://svn.pjsip.org/repos/pjproject/trunk@879 74dad513-b988-da41-8d7b-12977e46ad98

6 files changed, 215 insertions, 11 deletions

diff --git a/pjsip/include/pjsip-ua/sip_regc.h b/pjsip/include/pjsip-ua/sip_regc.h
index 04f2752d..683c3d48 100644
--- a/pjsip/include/pjsip-ua/sip_regc.h
+++ b/pjsip/include/pjsip-ua/sip_regc.h
@@ -26,6 +26,7 @@
 
 #include <pjsip/sip_types.h>
 #include <pjsip/sip_auth.h>
+#include <pjsip/sip_transport.h>
 
 
 /**
@@ -198,6 +199,32 @@ PJ_DECL(pj_status_t) pjsip_regc_set_credentials( pjsip_regc *regc,
 PJ_DECL(pj_status_t) pjsip_regc_set_route_set(pjsip_regc *regc,
 					      const pjsip_route_hdr*route_set);
 
+
+/**
+ * Lock/bind client registration to a specific transport/listener. 
+ * This is optional, as normally transport will be selected automatically
+ * based on the destination of requests upon resolver completion. 
+ * When the client registration is explicitly bound to the specific 
+ * transport/listener, all UAC transactions originated by the client
+ * registration will use the specified transport/listener when sending 
+ * outgoing requests.
+ *
+ * Note that this doesn't affect the Contact header set for this client
+ * registration. Application must manually update the Contact header if
+ * necessary, to adjust the address according to the transport being
+ * selected.
+ *
+ * @param regc	    The client registration instance.
+ * @param sel	    Transport selector containing the specification of
+ *		    transport or listener to be used by this session
+ *		    to send requests.
+ *
+ * @return	    PJ_SUCCESS on success, or the appropriate error code.
+ */
+PJ_DECL(pj_status_t) pjsip_regc_set_transport(pjsip_regc *regc,
+					      const pjsip_tpselector *sel);
+
+
 /**
  * Add headers to be added to outgoing REGISTER requests.
  *
diff --git a/pjsip/include/pjsip/sip_dialog.h b/pjsip/include/pjsip/sip_dialog.h
index b4d2a1ac..9cea4ded 100644
--- a/pjsip/include/pjsip/sip_dialog.h
+++ b/pjsip/include/pjsip/sip_dialog.h
@@ -28,6 +28,7 @@
 #include <pjsip/sip_msg.h>
 #include <pjsip/sip_auth.h>
 #include <pjsip/sip_errno.h>
+#include <pjsip/sip_transport.h>
 #include <pj/sock.h>
 #include <pj/assert.h>
 
@@ -134,6 +135,9 @@ struct pjsip_dialog
     /** Transaction counter. */
     int			tsx_count;  /**< Number of pending transactions.    */
 
+    /** Transport selector. */
+    pjsip_tpselector	tp_sel;
+
     /* Dialog usages. */
     unsigned		usage_cnt;  /**< Number of registered usages.	    */
     pjsip_module       *usage[PJSIP_MAX_MODULE]; /**< Array of usages, 
@@ -224,6 +228,30 @@ PJ_DECL(pj_status_t) pjsip_dlg_create_uas(  pjsip_user_agent *ua,
 
 
 /**
+ * Lock/bind dialog to a specific transport/listener. This is optional,
+ * as normally transport will be selected automatically based on the 
+ * destination of requests upon resolver completion. When the dialog is 
+ * explicitly bound to the specific transport/listener, all UAC transactions
+ * originated by this dialog will use the specified transport/listener
+ * when sending outgoing requests.
+ *
+ * Note that this doesn't affect the Contact header generated by this
+ * dialog. Application must manually update the Contact header if
+ * necessary, to adjust the address according to the transport being
+ * selected.
+ *
+ * @param dlg	    The dialog instance.
+ * @param sel	    Transport selector containing the specification of
+ *		    transport or listener to be used by this dialog
+ *		    to send requests.
+ *
+ * @return	    PJ_SUCCESS on success, or the appropriate error code.
+ */
+PJ_DECL(pj_status_t) pjsip_dlg_set_transport(pjsip_dialog *dlg,
+					     const pjsip_tpselector *sel);
+
+
+/**
  * Create a new (forked) dialog on receipt on forked response in rdata. 
  * The new dialog will be created from original_dlg, except that it will have
  * new remote tag as copied from the To header in the response. Upon return, 
diff --git a/pjsip/include/pjsip/sip_endpoint.h b/pjsip/include/pjsip/sip_endpoint.h
index 34413d7c..7f264908 100644
--- a/pjsip/include/pjsip/sip_endpoint.h
+++ b/pjsip/include/pjsip/sip_endpoint.h
@@ -352,18 +352,29 @@ PJ_DECL(pj_ioqueue_t*) pjsip_endpt_get_ioqueue(pjsip_endpoint *endpt);
 
 /**
  * Find a SIP transport suitable for sending SIP message to the specified
- * address. This function will complete asynchronously when the transport is
- * ready (for example, when TCP socket is connected), and when it completes,
- * the callback will be called with the status of the operation.
+ * address. If transport selector ("sel") is set, then the function will
+ * check if the transport selected is suitable to send requests to the
+ * specified address.
  *
- * @see pjsip_transport_get
+ * @see pjsip_tpmgr_acquire_transport
+ *
+ * @param endpt	    The SIP endpoint instance.
+ * @param type	    The type of transport to be acquired.
+ * @param remote    The remote address to send message to.
+ * @param addr_len  Length of the remote address.
+ * @param sel	    Optional pointer to transport selector instance which is
+ *		    used to find explicit transport, if required.
+ * @param p_tp	    Pointer to receive the transport instance, if one is found.
+ *
+ * @return	    PJ_SUCCESS on success, or the appropriate error code.
  */
 PJ_DECL(pj_status_t) 
 pjsip_endpt_acquire_transport( pjsip_endpoint *endpt,
 			       pjsip_transport_type_e type,
 			       const pj_sockaddr_t *remote,
 			       int addr_len,
-			       pjsip_transport **p_transport);
+			       const pjsip_tpselector *sel,
+			       pjsip_transport **p_tp);
 
 
 /*****************************************************************************
diff --git a/pjsip/include/pjsip/sip_errno.h b/pjsip/include/pjsip/sip_errno.h
index 10b542c7..bd0fecaf 100644
--- a/pjsip/include/pjsip/sip_errno.h
+++ b/pjsip/include/pjsip/sip_errno.h
@@ -214,6 +214,14 @@ PJ_BEGIN_DECL
  * transmit data has been deleted on return of pjsip_tx_data_dec_ref().
  */
 #define PJSIP_EBUFDESTROYED     (PJSIP_ERRNO_START_PJSIP + 63)	/* 171063 */
+/**
+ * @hideinitializer
+ * Unsuitable transport selected. This error occurs when application
+ * has explicitly requested to use a particular transport/listener,
+ * but the selected transport is not suitable to send request to
+ * the specified destination.
+ */
+#define PJSIP_ETPNOTSUITABLE	(PJSIP_ERRNO_START_PJSIP + 64)	/* 171064 */
 
 
 /************************************************************
diff --git a/pjsip/include/pjsip/sip_transaction.h b/pjsip/include/pjsip/sip_transaction.h
index e15fd13d..dfd00339 100644
--- a/pjsip/include/pjsip/sip_transaction.h
+++ b/pjsip/include/pjsip/sip_transaction.h
@@ -26,6 +26,7 @@
 
 #include <pjsip/sip_msg.h>
 #include <pjsip/sip_util.h>
+#include <pjsip/sip_transport.h>
 #include <pj/timer.h>
 
 PJ_BEGIN_DECL
@@ -96,6 +97,7 @@ struct pjsip_transaction
     pj_str_t			transaction_key;/**< Hash table key.        */
     pj_uint32_t			hashed_key;	/**< Key's hashed value.    */
     pj_str_t			branch;         /**< The branch Id.         */
+    pjsip_tpselector		tp_sel;		/**< Transport selector.    */
 
     /*
      * State and status.
@@ -214,6 +216,26 @@ PJ_DECL(pj_status_t) pjsip_tsx_create_uas( pjsip_module *tsx_user,
 
 
 /**
+ * Lock/bind transaction to a specific transport/listener. This is optional,
+ * as normally transport will be selected automatically based on the 
+ * destination of the request upon resolver completion. Also it's only valid
+ * for UAC transaction (to send outgoing request), since for UAS the
+ * transport will be selected according to rules about handling incoming
+ * request (most likely it will use the transport where the request is
+ * coming from if ";rport" parameter is present in Via header).
+ *
+ * @param tsx	    The UAC transaction.
+ * @param sel	    Transport selector containing the specification of
+ *		    transport or listener to be used by this transaction
+ *		    to send requests.
+ *
+ * @return	    PJ_SUCCESS on success, or the appropriate error code.
+ */
+PJ_DECL(pj_status_t) pjsip_tsx_set_transport(pjsip_transaction *tsx,
+					     const pjsip_tpselector *sel);
+
+
+/**
  * Call this function to manually feed a message to the transaction.
  * For UAS transaction, application MUST call this function after
  * UAS transaction has been created.
diff --git a/pjsip/include/pjsip/sip_transport.h b/pjsip/include/pjsip/sip_transport.h
index 4c9120e9..30516de7 100644
--- a/pjsip/include/pjsip/sip_transport.h
+++ b/pjsip/include/pjsip/sip_transport.h
@@ -55,6 +55,13 @@ PJ_BEGIN_DECL
  *
  *****************************************************************************/
 
+/*
+ * Forward declaration for transport factory (since it is referenced by
+ * the transport factory itself).
+ */
+typedef struct pjsip_tpfactory pjsip_tpfactory;
+
+
 /**
  * Flags for SIP transports.
  */
@@ -156,6 +163,76 @@ pjsip_transport_get_default_port_for_type(pjsip_transport_type_e type);
 PJ_DECL(const char*) pjsip_transport_get_type_name(pjsip_transport_type_e t);
 
 
+
+/*****************************************************************************
+ *
+ * TRANSPORT SELECTOR.
+ *
+ *****************************************************************************/
+
+/**
+ * This structure describes the type of data in pjsip_tpselector.
+ */
+typedef enum pjsip_tpselector_type
+{
+    /** Transport is not specified. */
+    PJSIP_TPSELECTOR_NONE,
+
+    /** Use the specific transport to send request. */
+    PJSIP_TPSELECTOR_TRANSPORT,
+
+    /** Use the specific listener to send request. */
+    PJSIP_TPSELECTOR_LISTENER,
+
+} pjsip_tpselector_type;
+
+
+/**
+ * This structure describes the transport/listener preference to be used
+ * when sending outgoing requests.
+ *
+ * Normally transport will be selected automatically according to rules about
+ * sending requests. But some applications (such as proxies or B2BUAs) may 
+ * want to explicitly use specific transport to send requests, for example
+ * when they want to make sure that outgoing request should go from a specific
+ * network interface.
+ *
+ * The pjsip_tpselector structure is used for that purpose, i.e. to allow
+ * application specificly request that a particular transport/listener
+ * should be used to send request. This structure is used when calling
+ * pjsip_tsx_set_transport() and pjsip_dlg_set_transport().
+ */
+typedef struct pjsip_tpselector
+{
+    /** The type of data in the union */
+    pjsip_tpselector_type   type;
+
+    /** Union representing the transport/listener criteria to be used. */
+    union {
+	pjsip_transport	*transport;
+	pjsip_tpfactory	*listener;
+    } u;
+
+} pjsip_tpselector;
+
+
+/**
+ * Add transport/listener reference in the selector to prevent the specified
+ * transport/listener from being destroyed while application still has
+ * reference to it.
+ *
+ * @param sel	The transport selector.
+ */
+PJ_DECL(void) pjsip_tpselector_add_ref(pjsip_tpselector *sel);
+
+
+/**
+ * Decrement transport/listener reference in the selector.
+ * @param sel	The transport selector
+ */
+PJ_DECL(void) pjsip_tpselector_dec_ref(pjsip_tpselector *sel);
+
+
 /*****************************************************************************
  *
  * RECEIVE DATA BUFFER.
@@ -431,6 +508,14 @@ struct pjsip_tx_data
 	char		     dst_name[16];  /**< Destination address.	*/
 	int		     dst_port;	    /**< Destination port.	*/
     } tp_info;
+
+    /** 
+     * Transport selector, to specify which transport to be used. 
+     * The value here must be set with pjsip_tx_data_set_transport(),
+     * to allow reference counter to be set properly.
+     */
+    pjsip_tpselector	    tp_sel;
+
 };
 
 
@@ -499,6 +584,20 @@ PJ_DECL(void) pjsip_tx_data_invalidate_msg( pjsip_tx_data *tdata );
  */
 PJ_DECL(char*) pjsip_tx_data_get_info( pjsip_tx_data *tdata );
 
+/**
+ * Set the explicit transport to be used when sending this transmit data.
+ * Application should not need to call this function, but rather use
+ * pjsip_tsx_set_transport() and pjsip_dlg_set_transport() instead (which
+ * will call this function).
+ *
+ * @param tdata	    The transmit buffer.
+ * @param sel	    Transport selector.
+ *
+ * @return	    PJ_SUCCESS on success.
+ */
+PJ_DECL(pj_status_t) pjsip_tx_data_set_transport(pjsip_tx_data *tdata,
+						 const pjsip_tpselector *sel);
+
 
 /*****************************************************************************
  *
@@ -706,12 +805,6 @@ PJ_DECL(pj_ssize_t) pjsip_tpmgr_receive_packet(pjsip_tpmgr *mgr,
  *
  *****************************************************************************/
 
-/*
- * Forward declaration for transport factory (since it is referenced by
- * the transport factory itself).
- */
-typedef struct pjsip_tpfactory pjsip_tpfactory;
-
 
 /**
  * A transport factory is normally used for connection oriented transports
@@ -859,11 +952,26 @@ PJ_DECL(void) pjsip_tpmgr_dump_transports(pjsip_tpmgr *mgr);
 /**
  * Find transport to be used to send message to remote destination. If no
  * suitable transport is found, a new one will be created.
+ *
+ * This is an internal function since normally application doesn't have access
+ * to transport manager. Application should use pjsip_endpt_acquire_transport()
+ * instead.
+ *
+ * @param mgr	    The transport manager instance.
+ * @param type	    The type of transport to be acquired.
+ * @param remote    The remote address to send message to.
+ * @param addr_len  Length of the remote address.
+ * @param sel	    Optional pointer to transport selector instance which is
+ *		    used to find explicit transport, if required.
+ * @param tp	    Pointer to receive the transport instance, if one is found.
+ *
+ * @return	    PJ_SUCCESS on success, or the appropriate error code.
  */
 PJ_DECL(pj_status_t) pjsip_tpmgr_acquire_transport(pjsip_tpmgr *mgr,
 						   pjsip_transport_type_e type,
 						   const pj_sockaddr_t *remote,
 						   int addr_len,
+						   const pjsip_tpselector *sel,
 						   pjsip_transport **tp);