MQTT 3.1.1 support - sessionPresent for MQTTClient

Bug: 436049

src/MQTTAsync.h

@@ -23,7 +23,7 @@
  * @cond MQTTAsync_main
  * @mainpage Asynchronous MQTT client library for C
  * 
- * © Copyright IBM Corp. 2009, 2013
+ * © Copyright IBM Corp. 2009, 2014
  * 
  * @brief An Asynchronous MQTT client library for C.
  *
@@ -333,6 +333,13 @@ typedef struct
 			MQTTAsync_message message;
 			char* destinationName;
 		} pub;
+		/* For connect, the server connected to, MQTT version used, and sessionPresent flag */
+		struct
+		{
+			char* serverURI;
+			int MQTTVersion;
+			int sessionPresent;
+		} connect;
 	} alt;
 } MQTTAsync_successData;
 

src/MQTTClient.c

@@ -762,6 +762,7 @@ int MQTTClient_connectURIVersion(MQTTClient handle, MQTTClient_connectOptions* o
 {
 	MQTTClients* m = handle;
 	int rc = SOCKET_ERROR;
+	int sessionPresent = 0;
 
 	FUNC_ENTRY;
 	if (m->ma && !running)
@@ -890,6 +891,8 @@ int MQTTClient_connectURIVersion(MQTTClient handle, MQTTClient_connectOptions* o
 				m->c->connected = 1;
 				m->c->good = 1;
 				m->c->connect_state = 0;
+				if (MQTTVersion == 4)
+					sessionPresent = connack->flags.bits.sessionPresent;
 				if (m->c->cleansession)
 					rc = MQTTClient_cleanSession(m->c);
 				if (m->c->outboundMsgs->count > 0)
@@ -910,9 +913,17 @@ int MQTTClient_connectURIVersion(MQTTClient handle, MQTTClient_connectOptions* o
 			m->pack = NULL;
 		}
 	}
-
 exit:
-	if (rc != MQTTCLIENT_SUCCESS)
+	if (rc == MQTTCLIENT_SUCCESS)
+	{
+		if (options->struct_version == 4) /* means we have to fill out return values */
+		{			
+			options->returned.serverURI = serverURI;
+			options->returned.MQTTVersion = MQTTVersion;    
+			options->returned.sessionPresent = sessionPresent;
+		}
+	}
+	else
 	{
 		Thread_unlock_mutex(mqttclient_mutex);
 		MQTTClient_disconnect1(handle, 0, 0, (MQTTVersion == 3)); /* not "internal" because we don't want to call connection lost */
@@ -1046,7 +1057,7 @@ int MQTTClient_connect(MQTTClient handle, MQTTClient_connectOptions* options)
 
 	if (strncmp(options->struct_id, "MQTC", 4) != 0 || 
 		(options->struct_version != 0 && options->struct_version != 1 && options->struct_version != 2
-			&& options->struct_version != 3))
+			&& options->struct_version != 3 && options->struct_version != 4))
 	{
 		rc = MQTTCLIENT_BAD_STRUCTURE;
 		goto exit;
@@ -1298,6 +1309,8 @@ int MQTTClient_subscribe(MQTTClient handle, char* topic, int qos)
 
 	FUNC_ENTRY;
 	rc = MQTTClient_subscribeMany(handle, 1, &topic, &qos);
+	if (qos == MQTT_BAD_SUBSCRIBE) /* addition for MQTT 3.1.1 - error code from subscribe */
+		rc = MQTT_BAD_SUBSCRIBE;
 	FUNC_EXIT_RC(rc);
 	return rc;
 }

src/MQTTClient.h

@@ -38,7 +38,7 @@
  * @endcond
  * @cond MQTTClient_main
  * @mainpage MQTT Client library for C
- * © Copyright IBM Corp. 2009, 2013
+ * © Copyright IBM Corp. 2009, 2014
  * 
  * @brief An MQTT client library in C.
  *
@@ -173,6 +173,10 @@
  * MQTT version to connect with: 3.1.1
  */
 #define MQTTVERSION_3_1_1 4
+/**
+ * Bad return code from subscribe, as defined in the 3.1.1 specification
+ */
+#define MQTT_BAD_SUBSCRIBE 0x80
 
 /**
  * A handle representing an MQTT client. A valid client handle is available
@@ -504,11 +508,12 @@ typedef struct
 {
 	/** The eyecatcher for this structure.  must be MQTC. */
 	char struct_id[4];
-	/** The version number of this structure.  Must be 0, 1, 2 or 3.  
-	  * 0 signifies no SSL options and no serverURIs
-	  * 1 signifies no serverURIs 
-      * 2 signifies no MQTTVersion
-	  */
+	/** The version number of this structure.  Must be 0, 1, 2, 3 or 4.  
+	 * 0 signifies no SSL options and no serverURIs
+	 * 1 signifies no serverURIs 
+	 * 2 signifies no MQTTVersion
+	 * 3 signifies no returned values
+	 */
 	int struct_version;
 	/** The "keep alive" interval, measured in seconds, defines the maximum time
    * that should pass without communication between the client and the server
@@ -599,15 +604,24 @@ typedef struct
    */    
 	char** serverURIs;
 	/**
-      * Sets the version of MQTT to be used on the connect.
-      * MQTTVERSION_DEFAULT (0) = default: start with 3.1.1, and if that fails, fall back to 3.1
-      * MQTTVERSION_3_1 (3) = only try version 3.1
-      * MQTTVERSION_3_1_1 (4) = only try version 3.1.1
-	  */
+	 * Sets the version of MQTT to be used on the connect.
+	 * MQTTVERSION_DEFAULT (0) = default: start with 3.1.1, and if that fails, fall back to 3.1
+	 * MQTTVERSION_3_1 (3) = only try version 3.1
+	 * MQTTVERSION_3_1_1 (4) = only try version 3.1.1
+	 */
 	int MQTTVersion;
+	/**
+	 * Returned from the connect when the MQTT version used to connect is 3.1.1
+	 */
+	struct 
+	{
+		char* serverURI;     /**< the serverURI connected to */
+		int MQTTVersion;     /**< the MQTT version used to connect with */
+		int sessionPresent;  /**< if the MQTT version is 3.1.1, the value of sessionPresent returned in the connack */
+	} returned;
 } MQTTClient_connectOptions;
 
-#define MQTTClient_connectOptions_initializer { {'M', 'Q', 'T', 'C'}, 3, 60, 1, 1, NULL, NULL, NULL, 30, 20, NULL, 0, NULL, 0}
+#define MQTTClient_connectOptions_initializer { {'M', 'Q', 'T', 'C'}, 4, 60, 1, 1, NULL, NULL, NULL, 30, 20, NULL, 0, NULL, 0}
 
 /**
   * MQTTClient_libraryInfo is used to store details relating to the currently used

src/MQTTPacket.h

 /*******************************************************************************
- * Copyright (c) 2009, 2013 IBM Corp.
+ * Copyright (c) 2009, 2014 IBM Corp.
  *
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
@@ -13,6 +13,7 @@
  * Contributors:
  *    Ian Craggs - initial API and implementation and/or initial documentation
  *    Ian Craggs, Allan Stockdill-Mander - SSL updates
+ *    Ian Craggs - MQTT 3.1.1 support
  *******************************************************************************/
 
 #if !defined(MQTTPACKET_H)
@@ -120,6 +121,23 @@ typedef struct
 typedef struct
 {
 	Header header; /**< MQTT header byte */
+	union
+	{
+		unsigned char all;	/**< all connack flags */
+#if defined(REVERSED)
+		struct
+		{
+			unsigned int reserved : 7;	/**< message type nibble */
+			bool sessionPresent : 1;    /**< was a session found on the server? */
+		} bits;
+#else
+		struct
+		{
+			bool sessionPresent : 1;    /**< was a session found on the server? */
+			unsigned int reserved : 7;	/**< message type nibble */
+		} bits;
+#endif
+	} flags;	 /**< connack flags byte */
 	char rc; /**< connack return code */
 } Connack;
 

src/MQTTPacketOut.c

@@ -123,7 +123,7 @@ void* MQTTPacket_connack(unsigned char aHeader, char* data, int datalen)
 
 	FUNC_ENTRY;
 	pack->header.byte = aHeader;
-	readChar(&curdata);	/* reserved byte */
+	pack->flags.all = readChar(&curdata);
 	pack->rc = readChar(&curdata);
 	FUNC_EXIT;
 	return pack;