[0.78.3] ignore old-style timebase masters

git-svn-id: svn+ssh://jackaudio.org/trunk/jack@460 0c269be4-1314-0410-8aa9-9f06e86f4224

configure.in

@@ -14,7 +14,7 @@ dnl                 changes are made
 dnl ---
 JACK_MAJOR_VERSION=0
 JACK_MINOR_VERSION=78
-JACK_MICRO_VERSION=2
+JACK_MICRO_VERSION=3
 
 dnl ---
 dnl HOWTO: updating the jack protocal version

doc/transport.dox

@@ -41,7 +41,7 @@ are in <jack/transport.h>
   - We want a way for clients with heavyweight state to sync up when
   the user presses "play", before the transport starts rolling.
 
-  - We need to provide for ongoing binary compatibility as the
+  - We want to provide for ongoing binary compatibility as the
   transport design evolves.
 
 
@@ -52,7 +52,8 @@ The former transport master role has been divided into two layers:
   - @ref timebase - counting beats, frames, etc. on every cycle.
   - @ref transportcontrol - start, stop and reposition the playback.  
 
-Existing clients continue to work in compatibility mode.
+Existing transport clients continue to work in compatibility mode.
+But, old-style timebase masters will no longer control the transport.
 
 
 @subsection timebase Timebase Master
@@ -171,7 +172,6 @@ will enter the ::JackTransportStarting state and begin invoking their
 
 
 @image html	fsm.png "Transport State Transition Diagram"
-@image latex	fsm.png "Transport State Transition Diagram"
 
 
 @subsection transportclients Transport Clients
@@ -191,27 +191,35 @@ cycle and the state returned is valid for the entire cycle.
 
 @subsection compatibility Compatibility
 
-We want to support the existing functions in compatibility mode as
-deprecated interfaces for a while.  The main reasons are:
+During the transition period we will support the old-style interfaces
+in compatibility mode as deprecated interfaces.  This compatibility is
+not 100%, there are limitations.  
+
+The main reasons for doing this are:
 
   - facilitate testing with clients that already have transport
   support
   - provide a clean migration path, so application developers are
   not discouraged from supporting the transport interface
-  - inter-operate with ardour 0.9 beta.
 
-So, these interfaces continue to be supported (but deprecated):
+These deprecated interfaces continue to work:
 
 @code
   typedef struct jack_transport_info_t;
 
-  void jack_set_transport_info (jack_client_t *client,
-                                jack_transport_info_t *tinfo);
   void jack_get_transport_info (jack_client_t *client,
                                 jack_transport_info_t *tinfo);
-  int  jack_engine_takeover_timebase (jack_client_t *);
 @endcode
 
+Unfortunately, the old-style timebase master interface cannot coexist
+cleanly with such new features as jack_transport_locate() and
+slow-sync clients.  So, these interfaces are only present as stubs:
+
+@code
+  void jack_set_transport_info (jack_client_t *client,
+                                jack_transport_info_t *tinfo);
+  int  jack_engine_takeover_timebase (jack_client_t *);
+@endcode
 
 For compatibility with future changes, it would be good to avoid
 structures entirely.  Nevertheless, the jack_position_t structure
@@ -238,7 +246,4 @@ will probably not be included in JACK release 1.0.
   are addressed there's no reason to retain those two SMPTE fields in
   the jack_position_t structure.
   - looping -- unless we get feedback that this is really required
-  - internal timebase master or slow-sync clients
-       - probably a good idea
-       - haven't studied it
 */

jack/internal.h

@@ -103,6 +103,7 @@ typedef struct {
     jack_position_t	  pending_time;	/* position for next cycle */
     jack_position_t	  request_time;	/* latest requested position */
     jack_unique_t	  prev_request; /* previous request unique ID */
+    volatile int	  seq_number;	/* unique ID sequence number */
     int			  new_pos;	/* new position this cycle */
     unsigned long	  sync_clients;	/* number of is_slowsync clients */
     unsigned long	  sync_remain;	/* number of them with sync_poll */
@@ -119,7 +120,6 @@ typedef struct {
     float                 cpu_load;
     unsigned long         port_max;
     int                   engine_ok;
-    jack_engine_t        *engine;
     unsigned long         n_port_types;
     jack_port_type_info_t port_types[JACK_MAX_PORT_TYPES];
     jack_port_shared_t    ports[0];

jack/jack.h

@@ -536,16 +536,14 @@ jack_port_t *jack_port_by_name (jack_client_t *, const char *portname);
 jack_port_t *jack_port_by_id (const jack_client_t *client, jack_port_id_t id);
 
 /**
- * If a client is told (by the user) to become the timebase for the
- * entire system, it calls this function. If it returns zero, then the
- * client has the responsibility to call jack_set_transport_info() at
- * the end of its process callback.
+ * Old-style interface to become the timebase for the entire JACK
+ * subsystem.
  *
- * @deprecated This function is only for compatibility with earlier
- * transport implementations.  Instead, see <jack/transport.h> and use
- * jack_set_timebase_callback().
+ * @deprecated This function still exists for compatibility with the
+ * earlier transport interface, but it does nothing.  Instead, see
+ * <jack/transport.h> and use jack_set_timebase_callback().
  *
- * @return 0 on success, otherwise a non-zero error code
+ * @return ENOSYS, function not implemented.
  */
 int  jack_engine_takeover_timebase (jack_client_t *);
 

jack/transport.h

@@ -387,16 +387,9 @@ void jack_get_transport_info (jack_client_t *client,
 /**
  * Set the transport info structure (deprecated).
  *
- * @param client the JACK client structure.
- * @param tinfo used to return a new transport info structure used
- * for the next process cycle.  The "valid" field must say which
- * fields contain valid data.
- *
- * @deprecated This is for compatibility with the earlier transport
- * interface.  Define a ::JackTimebaseCallback, instead.
- *
- * @pre Caller must be the current timebase master.  Must be called
- * from the process thread.
+ * @deprecated This function still exists for compatibility with the
+ * earlier transport interface, but it does nothing.  Instead, define
+ * a ::JackTimebaseCallback.
  */
 void jack_set_transport_info (jack_client_t *client,
 			      jack_transport_info_t *tinfo);

jackd/engine.c

@@ -1740,7 +1740,6 @@ jack_engine_new (int realtime, int rtpriority, int verbose, int client_timeout)
 	jack_register_shm (engine->control_shm_name, addr, shmid);
 	
 	engine->control = (jack_control_t *) addr;
-	engine->control->engine = engine;
 
 	/* setup port type information from builtins. buffer space is allocated
 	   whenever we call jack_set_buffer_size()

jackd/transengine.c

@@ -234,6 +234,7 @@ jack_transport_init (jack_engine_t *engine)
 	memset (&ectl->pending_time, 0, sizeof(ectl->pending_time));
 	memset (&ectl->request_time, 0, sizeof(ectl->request_time));
 	ectl->prev_request = 0;
+	ectl->seq_number = 1;		/* can't start at 0 */
 	ectl->new_pos = 0;
 	ectl->sync_remain = 0;
 	ectl->sync_clients = 0;
@@ -305,8 +306,7 @@ jack_transport_client_set_sync (jack_engine_t *engine,
 	int ret;
 	jack_client_internal_t *client;
 
-	// JOQ: I am assuming the process cycle is serialized with
-	// respect to this lock...
+	/* The process cycle runs with this lock. */
 	jack_lock_graph (engine);
 
 	client = jack_client_internal_by_id (engine, client_id);

libjack/transclient.c

@@ -373,9 +373,14 @@ jack_transport_stop (jack_client_t *client)
 
 /************* Compatibility with old transport API. *************/
 
+#define OLD_TIMEBASE_BROKEN
+
 int
 jack_engine_takeover_timebase (jack_client_t *client)
 {
+#ifdef OLD_TIMEBASE_BROKEN
+	return ENOSYS;
+#else
 	jack_request_t req;
 
 	req.type = SetTimeBaseClient;
@@ -383,6 +388,7 @@ jack_engine_takeover_timebase (jack_client_t *client)
 	req.x.timebase.conditional = 0;
 
 	return jack_client_deliver_request (client, &req);
+#endif /* OLD_TIMEBASE_BROKEN */
 }	
 
 void
@@ -416,12 +422,20 @@ jack_get_transport_info (jack_client_t *client,
 	}
 }
 
-static int first_error = 1;
-
 void
 jack_set_transport_info (jack_client_t *client,
 			 jack_transport_info_t *info)
 {
+	static int first_error = 1;
+
+#ifdef OLD_TIMEBASE_BROKEN
+
+	if (first_error)
+		jack_error ("jack_set_transport_info() no longer supported.");
+	first_error = 0;
+
+#else
+
 	jack_control_t *ectl = client->engine;
 
 	if (!client->control->is_timebase) { /* not timebase master? */
@@ -470,6 +484,7 @@ jack_set_transport_info (jack_client_t *client,
 		ectl->pending_time.ticks_per_beat = info->ticks_per_beat;
 		ectl->pending_time.beats_per_minute = info->beats_per_minute;
 	}
+#endif /* OLD_TIMEBASE_BROKEN */
 }	
 
 #endif /* OLD_TRANSPORT */