DNS-SD Server

This module includes APIs for DNS-SD server.

Summary

Enumerations
otDnssdQueryType{   OT_DNSSD_QUERY_TYPE_NONE = 0,   OT_DNSSD_QUERY_TYPE_BROWSE = 1,   OT_DNSSD_QUERY_TYPE_RESOLVE = 2,   OT_DNSSD_QUERY_TYPE_RESOLVE_HOST = 3 }	enum This enumeration specifies a DNS-SD query type.

Typedefs
otDnssdCounters	typedef struct otDnssdCounters This structure contains the counters of DNS-SD server.
otDnssdHostInfo	typedef struct otDnssdHostInfo This structure represents information of a discovered host for a DNS-SD query.
otDnssdQuery	typedef void This opaque type represents a DNS-SD query.
otDnssdQuerySubscribeCallback)(void *aContext, const char *aFullName)	typedef void(* This function is called when a DNS-SD query subscribes one of:
otDnssdQueryUnsubscribeCallback)(void *aContext, const char *aFullName)	typedef void(* This function is called when a DNS-SD query unsubscribes one of:
otDnssdServiceInstanceInfo	typedef struct otDnssdServiceInstanceInfo This structure represents information of a discovered service instance for a DNS-SD query.

Functions
otDnssdGetCounters(otInstance *aInstance)	const otDnssdCounters * This function returns the counters of the DNS-SD server.
otDnssdGetNextQuery(otInstance *aInstance, const otDnssdQuery *aQuery)	const otDnssdQuery * This function acquires the next query in the DNS-SD server.
otDnssdGetQueryTypeAndName(const otDnssdQuery *aQuery, char(*) aNameOutput[OT_DNS_MAX_NAME_SIZE])	otDnssdQueryType This function acquires the DNS-SD query type and name for a specific query.
otDnssdQueryHandleDiscoveredHost(otInstance *aInstance, const char *aHostFullName, otDnssdHostInfo *aHostInfo)	void This function notifies a discovered host.
otDnssdQueryHandleDiscoveredServiceInstance(otInstance *aInstance, const char *aServiceFullName, otDnssdServiceInstanceInfo *aInstanceInfo)	void This function notifies a discovered service instance.
otDnssdQuerySetCallbacks(otInstance *aInstance, otDnssdQuerySubscribeCallback aSubscribe, otDnssdQueryUnsubscribeCallback aUnsubscribe, void *aContext)	void This function sets DNS-SD server query callbacks.

Structs
otDnssdCounters	This structure contains the counters of DNS-SD server.
otDnssdHostInfo	This structure represents information of a discovered host for a DNS-SD query.
otDnssdServiceInstanceInfo	This structure represents information of a discovered service instance for a DNS-SD query.

Enumerations

otDnssdQueryType

 otDnssdQueryType

This enumeration specifies a DNS-SD query type.

Properties
OT_DNSSD_QUERY_TYPE_BROWSE	Service type browse service.
OT_DNSSD_QUERY_TYPE_NONE	Service type unspecified.
OT_DNSSD_QUERY_TYPE_RESOLVE	Service type resolve service instance.
OT_DNSSD_QUERY_TYPE_RESOLVE_HOST	Service type resolve hostname.

Typedefs

otDnssdCounters

struct otDnssdCounters otDnssdCounters

This structure contains the counters of DNS-SD server.

otDnssdHostInfo

struct otDnssdHostInfo otDnssdHostInfo

This structure represents information of a discovered host for a DNS-SD query.

otDnssdQuery

void otDnssdQuery

This opaque type represents a DNS-SD query.

otDnssdQuerySubscribeCallback

void(* otDnssdQuerySubscribeCallback)(void *aContext, const char *aFullName)

This function is called when a DNS-SD query subscribes one of:

1. a service name.
2. a service instance name.
3. a host name.

The DNS-SD query implementation is responsible for identifying what aFullName is. If aFullName is a service name or service instance name, the DNS-SD query implementation should discover corresponding service instance information and notify the DNS-SD server using otDnssdQueryHandleDiscoveredServiceInstance. If aFullName is a host name, the DNS-SD query implementation should discover the host information and notify the DNS-SD server using otDnssdQueryHandleDiscoveredHost.

Note: There can be multiple subscription to the same name. DNS-SD query implementation should record the number of active subscriptions and stop notifying when there is no active subscription for aFullName.

Details
Parameters	[in] aContext A pointer to the application-specific context. [in] aFullName The null-terminated full service name (e.g. "_ipps._tcp.default.service.arpa."), or full service instance name (e.g. "OpenThread._ipps._tcp.default.service.arpa."), or full host name (e.g. "ot-host.default.service.arpa.").

See also:
otDnssdQueryHandleDiscoveredServiceInstance
otDnssdQueryHandleDiscoveredHost

otDnssdQueryUnsubscribeCallback

void(* otDnssdQueryUnsubscribeCallback)(void *aContext, const char *aFullName)

This function is called when a DNS-SD query unsubscribes one of:

1. a service name.
2. a service instance name.
3. a host name.

The DNS-SD query implementation is responsible for identifying what aFullName is.

Note: There can be multiple subscription to the same name. DNS-SD query implementation should record the number of active subscriptions and stop notifying when there is no active subscription for aFullName.

Details
Parameters	[in] aContext A pointer to the application-specific context. [in] aFullName The null-terminated full service name (e.g. "_ipps._tcp.default.service.arpa."), or full service instance name (e.g. "OpenThread._ipps._tcp.default.service.arpa.").

otDnssdServiceInstanceInfo

struct otDnssdServiceInstanceInfo otDnssdServiceInstanceInfo

This structure represents information of a discovered service instance for a DNS-SD query.

Functions

otDnssdGetCounters

const otDnssdCounters * otDnssdGetCounters(
  otInstance *aInstance
)

This function returns the counters of the DNS-SD server.

Details
Parameters	[in] aInstance The OpenThread instance structure.
Returns	A pointer to the counters of the DNS-SD server.

otDnssdGetNextQuery

const otDnssdQuery * otDnssdGetNextQuery(
  otInstance *aInstance,
  const otDnssdQuery *aQuery
)

This function acquires the next query in the DNS-SD server.

Details
Parameters	[in] aInstance The OpenThread instance structure. [in] aQuery The query pointer. Pass NULL to get the first query.
Returns	A pointer to the query or NULL if no more queries.

otDnssdGetQueryTypeAndName

otDnssdQueryType otDnssdGetQueryTypeAndName(
  const otDnssdQuery *aQuery,
  char(*) aNameOutput[OT_DNS_MAX_NAME_SIZE]
)

This function acquires the DNS-SD query type and name for a specific query.

Details
Parameters	[in] aQuery The query pointer acquired from otDnssdGetNextQuery. [out] aNameOutput The name output buffer, which should be OT_DNS_MAX_NAME_SIZE bytes long.
Returns	The DNS-SD query type.

otDnssdQueryHandleDiscoveredHost

void otDnssdQueryHandleDiscoveredHost(
  otInstance *aInstance,
  const char *aHostFullName,
  otDnssdHostInfo *aHostInfo
)

This function notifies a discovered host.

The external query resolver (e.g. Discovery Proxy) should call this function to notify OpenThread core of the subscribed hosts.

Note: aHostInfo must not contain unspecified or link-local or loop-back or multicast IP addresses.

Details
Parameters	[in] aInstance The OpenThread instance structure. [in] aHostFullName The null-terminated full host name. [in] aHostInfo A pointer to the discovered service instance information.

otDnssdQueryHandleDiscoveredServiceInstance

void otDnssdQueryHandleDiscoveredServiceInstance(
  otInstance *aInstance,
  const char *aServiceFullName,
  otDnssdServiceInstanceInfo *aInstanceInfo
)

This function notifies a discovered service instance.

The external query resolver (e.g. Discovery Proxy) should call this function to notify OpenThread core of the subscribed services or service instances.

Note: aInstanceInfo must not contain unspecified or link-local or loop-back or multicast IP addresses.

Details
Parameters	[in] aInstance The OpenThread instance structure. [in] aServiceFullName The null-terminated full service name. [in] aInstanceInfo A pointer to the discovered service instance information.

otDnssdQuerySetCallbacks

void otDnssdQuerySetCallbacks(
  otInstance *aInstance,
  otDnssdQuerySubscribeCallback aSubscribe,
  otDnssdQueryUnsubscribeCallback aUnsubscribe,
  void *aContext
)

This function sets DNS-SD server query callbacks.

The DNS-SD server calls aSubscribe to subscribe to a service or service instance to resolve a DNS-SD query and aUnsubscribe to unsubscribe when the query is resolved or timeout.

Note: aSubscribe and aUnsubscribe must be both set or unset.

Details
Parameters	[in] aInstance The OpenThread instance structure. [in] aSubscribe A pointer to the callback function to subscribe a service or service instance. [in] aUnsubscribe A pointer to the callback function to unsubscribe a service or service instance. [in] aContext A pointer to the application-specific context.

Resources

OpenThread API Reference topics originate from the source code, available on GitHub. For more information, or to contribute to our documentation, refer to Resources.