Diff: MQTTUnsubscribeClient.c

Revision:

0:7734401cc1b4

Child:

7:1b8fb13fc6ef

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MQTTUnsubscribeClient.c	Tue Feb 04 22:31:32 2014 +0000
@@ -0,0 +1,105 @@
+/*******************************************************************************
+ * Copyright (c) 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
+ * and Eclipse Distribution License v1.0 which accompany this distribution.
+ *
+ * The Eclipse Public License is available at
+ *    http://www.eclipse.org/legal/epl-v10.html
+ * and the Eclipse Distribution License is available at
+ *   http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * Contributors:
+ *    Ian Craggs - initial API and implementation and/or initial documentation
+ *******************************************************************************/
+
+#include "MQTTPacket.h"
+#include "StackTrace.h"
+
+#include <string.h>
+
+/**
+  * Determines the length of the MQTT unsubscribe packet that would be produced using the supplied parameters
+  * @param count the number of topic filter strings in topicFilters
+  * @param topicFilters the array of topic filter strings to be used in the publish
+  * @return the length of buffer needed to contain the serialized version of the packet
+  */
+int MQTTSerialize_unsubscribeLength(int count, MQTTString topicFilters[])
+{
+	int i;
+	int len = 2; /* packetid */
+
+	for (i = 0; i < count; ++i)
+		len += 2 + MQTTstrlen(topicFilters[i]); /* length + topic*/
+	return len;
+}
+
+
+/**
+  * Serializes the supplied unsubscribe data into the supplied buffer, ready for sending
+  * @param buf the raw buffer data, of the correct length determined by the remaining length field
+  * @param buflen the length in bytes of the data in the supplied buffer
+  * @param dup integer - the MQTT dup flag
+  * @param packetid integer - the MQTT packet identifier
+  * @param count - number of members in the topicFilters array
+  * @param topicFilters - array of topic filter names
+  * @return the length of the serialized data.  <= 0 indicates error
+  */
+int MQTTSerialize_unsubscribe(char* buf, int buflen, int dup, int packetid, int count, MQTTString topicFilters[])
+{
+	char *ptr = buf;
+	MQTTHeader header;
+	int rem_len = 0;
+	int rc = -1;
+	int i = 0;
+
+	FUNC_ENTRY;
+	if (MQTTPacket_len(rem_len = MQTTSerialize_unsubscribeLength(count, topicFilters)) > buflen)
+	{
+		rc = MQTTPACKET_BUFFER_TOO_SHORT;
+		goto exit;
+	}
+
+	header.byte = 0;
+	header.bits.type = SUBSCRIBE;
+	header.bits.dup = dup;
+	header.bits.qos = 1;
+	writeChar(&ptr, header.byte); /* write header */
+
+	ptr += MQTTPacket_encode(ptr, rem_len); /* write remaining length */;
+
+	writeInt(&ptr, packetid);
+
+	for (i = 0; i < count; ++i)
+		writeMQTTString(&ptr, topicFilters[i]);
+
+	rc = ptr - buf;
+exit:
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+
+/**
+  * Deserializes the supplied (wire) buffer into unsuback data
+  * @param packetid returned integer - the MQTT packet identifier
+  * @param buf the raw buffer data, of the correct length determined by the remaining length field
+  * @param buflen the length in bytes of the data in the supplied buffer
+  * @return error code.  1 is success, 0 is failure
+  */
+int MQTTDeserialize_unsuback(int* packetid, char* buf, int buflen)
+{
+	int type = 0;
+	int dup = 0;
+	int rc = 0;
+
+	FUNC_ENTRY;
+	rc = MQTTDeserialize_ack(&type, &dup, packetid, buf, buflen);
+	if (type == UNSUBACK)
+		rc = 1;
+	FUNC_EXIT_RC(rc);
+	return rc;
+}
+
+