Functions used for working with topic details (TOPIC_DETAILS_T). More...

Functions
TOPIC_DETAILS_T *	create_topic_details_none (void)
	Create a TOPIC_DETAILS_T which describes a topic with no topic details.

TOPIC_DETAILS_T *	create_topic_details_stateless (void)
	Create a TOPIC_DETAILS_T which describes a stateless topic, ie one that delegates its content to a publisher or control client.

TOPIC_DETAILS_T *	create_topic_details_single_value (const M_DATA_TYPE_T type)
	Create a TOPIC_DETAILS_T which describes a topic with a simple value.

TOPIC_DETAILS_T *	create_topic_details_record (void)
	Create a TOPIC_DETAILS_T which for a topic with records and fields. More...

TOPIC_DETAILS_T *	create_topic_details_slave (const char *const master_topic)
	Create a TOPIC_DETAILS_T for a slave topic. More...

BUF_T *	topic_details_schema_build (const TOPIC_DETAILS_T *details)
	Creates an XML document that represents the topic details that has been passed as an argument. More...

BUF_T *	topic_details_marshal (TOPIC_DETAILS_T *details)
	Take existing topic details (with an associated schema) and serialise into a form suitable for transmitting over the wire to Diffusion.

TOPIC_DETAILS_T *	topic_details_dup (const TOPIC_DETAILS_T *src)
	Create a duplicate (copy) of an existing TOPIC_DETAILS_T.

void	topic_details_free (TOPIC_DETAILS_T *details)
	Free memory associated with a TOPIC_DETAILS_T.

char *	set_empty_field_value (const TOPIC_DETAILS_T details, const char value)
	Set the empty field value (record topic data only). More...

char *	get_empty_field_value (const TOPIC_DETAILS_T *details)
	Get the current empty field value (record topic data only). More...

Detailed Description

Functions used for working with topic details (TOPIC_DETAILS_T).

Topic details describe the structure of a topic.

If you intend to create many topics which have the same type of topic details, e.g. single value string topics, then it is recommended that you only create a single instance of topic details to describe them. This will allow the server to cache the details, significantly improving performance and reducing memory load.

Use is subject to license terms.

NOTICE: All information contained herein is, and remains the property of Push Technology. The intellectual and technical concepts contained herein are proprietary to Push Technology and may be covered by U.S. and Foreign Patents, patents in process, and are protected by trade secret or copyright law.

Function Documentation

TOPIC_DETAILS_T* create_topic_details_record ( void )

Create a TOPIC_DETAILS_T which for a topic with records and fields.

The schema describing the structure of these records and fields must be provided separately.

TOPIC_DETAILS_T* create_topic_details_slave ( const char *const master_topic )

Create a TOPIC_DETAILS_T for a slave topic.

This function will return NULL if master_topic is NULL.

Parameters

master_topic The full path of the topic to which the slave topic shall be an alias.

char* get_empty_field_value ( const TOPIC_DETAILS_T * details )

Get the current empty field value (record topic data only).

This returns the value used to distinguish between a field which is unchanged from one which is merely empty. A value of NULL indicates that this value has never been set, and is treated internally as an empty string.

Parameters

details Record topic details.

Returns: The value used to represent empty fields, or NULL.

char* set_empty_field_value	(	const TOPIC_DETAILS_T *	details,
		const char *	value
	)

Set the empty field value (record topic data only).

For a client to differentiate between unchanged fields and empty fields in delta messages, it's necessary to use a special value to represent an empty field.

Parameters

details	Topic details for which to set the value.
value	New value for empty fields, or NULL to reset to the default (an empty string).

Returns: The previous value.

BUF_T* topic_details_schema_build ( const TOPIC_DETAILS_T * details )

Creates an XML document that represents the topic details that has been passed as an argument.

The XML is serialised to a BUF_T for transmission to Diffusion when creating new topics.