[0.99.37] better jack_client_open() error checking

git-svn-id: svn+ssh://jackaudio.org/trunk/jack@847 0c269be4-1314-0410-8aa9-9f06e86f4224

configure.ac

@@ -15,7 +15,7 @@ dnl                 changes are made
 dnl ---
 JACK_MAJOR_VERSION=0
 JACK_MINOR_VERSION=99
-JACK_MICRO_VERSION=36
+JACK_MICRO_VERSION=37
 
 dnl ---
 dnl HOWTO: updating the jack protocol version
@@ -25,7 +25,7 @@ dnl made to the way libjack communicates with jackd
 dnl that would break applications linked with an older
 dnl version of libjack.
 dnl ---
-JACK_PROTOCOL_VERSION=14
+JACK_PROTOCOL_VERSION=15
 
 dnl ---
 dnl HOWTO: updating the libjack interface version

jack/internal.h

@@ -250,6 +250,7 @@ typedef volatile struct {
 
 typedef struct {
     
+    uint32_t	protocol_v;		/* protocol version, must go first */
     int32_t    load;
     ClientType type;
     jack_options_t options;
@@ -262,7 +263,6 @@ typedef struct {
 
 typedef struct {
 
-    uint32_t	protocol_v;
     jack_status_t status;
 
     jack_shm_info_t client_shm;

jack/types.h

@@ -351,7 +351,17 @@ enum JackStatus {
      /**
       * Unable to initialize client
       */
-     JackInitFailure = 0x100
+     JackInitFailure = 0x100,
+
+     /**
+      * Unable to access shared memory
+      */
+     JackShmFailure = 0x200,
+
+     /**
+      * Client's protocol version does not match
+      */
+     JackVersionError = 0x400
 };
 
 /**

jackd/clientengine.c

@@ -650,10 +650,25 @@ jack_client_create (jack_engine_t *engine, int client_fd)
 	jack_client_internal_t *client;
 	jack_client_connect_request_t req;
 	jack_client_connect_result_t res;
+	ssize_t nbytes;
 
 	res.status = 0;
 
-	if (read (client_fd, &req, sizeof (req)) != sizeof (req)) {
+	nbytes = read (client_fd, &req, sizeof (req));
+
+	if ((nbytes < sizeof (req.protocol_v))
+	    || (req.protocol_v != jack_protocol_version)) {
+
+		/* JACK protocol incompatibility */
+		res.status |= (JackFailure|JackVersionError);
+		jack_error ("JACK protocol mismatch");
+		if (write (client_fd, &res, sizeof (res)) != sizeof (res)) {
+			jack_error ("cannot write client connection response");
+		}
+		return -1;
+	}
+
+	if (nbytes != sizeof (req)) {
 		jack_error ("cannot read connection request from client");
 		return -1;
 	}
@@ -680,7 +695,6 @@ jack_client_create (jack_engine_t *engine, int client_fd)
 		res.status |= JackFailure; /* just making sure */
 		return -1;
 	}
-	res.protocol_v = jack_protocol_version;
 	res.client_shm = client->control_shm;
 	res.engine_shm = engine->control_shm;
 	res.realtime = engine->control->real_time;
@@ -699,7 +713,7 @@ jack_client_create (jack_engine_t *engine, int client_fd)
 		strcpy (res.fifo_prefix, engine->fifo_prefix);
 	}
 
-	if (write (client->request_fd, &res, sizeof (res)) != sizeof (res)) {
+	if (write (client_fd, &res, sizeof (res)) != sizeof (res)) {
 		jack_error ("cannot write connection response to client");
 		jack_client_delete (engine, client);
 		return -1;

jackd/engine.c

@@ -1489,12 +1489,6 @@ jack_server_thread (void *arg)
 	return 0;
 }
 
-
-static void
-jack_engine_reset_frame_timer (jack_engine_t* engine)
-{
-}
-
 jack_engine_t *
 jack_engine_new (int realtime, int rtpriority, int do_mlock, int do_unlock,
 		 const char *server_name, int temporary, int verbose,

libjack/client.c

@@ -600,6 +600,8 @@ jack_request_client (ClientType type,
 		*status |= JackServerStarted;
 	}
 
+	/* format connection request */
+	req.protocol_v = jack_protocol_version;
 	req.load = TRUE;
 	req.type = type;
 	snprintf (req.name, sizeof (req.name),
@@ -641,18 +643,15 @@ jack_request_client (ClientType type,
 	*status |= res->status;		/* return server status bits */
 
 	if (*status & JackFailure) {
-		jack_error ("could not attach as client");
+		if (*status & JackVersionError) {
+			jack_error ("client linked with incompatible libjack"
+				    " version.");
+		}
+		jack_error ("could not attach to JACK server");
 		*status |= JackServerError;
 		goto fail;
 	}
 
-	if (res->protocol_v != jack_protocol_version){
-		jack_error ("application linked against incompatible libjack"
-			    " version.");
-		*status |= (JackFailure|JackServerError);
-		goto fail;
-	}
-
 	switch (type) {
 	case ClientDriver:
 	case ClientInternal:
@@ -788,6 +787,7 @@ jack_client_open (const char *client_name,
 	/* don't access shared memory until server connected */
 	if (jack_initialize_shm ()) {
 		jack_error ("Unable to initialize shared memory.");
+		*status |= (JackFailure|JackShmFailure);
 		return NULL;
 	}