mbed-os/features/FEATURE_BLE/ble/ServiceDiscovery.h

184 lines
8.0 KiB
C++

/* mbed Microcontroller Library
* Copyright (c) 2006-2013 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef __SERVICE_DISOVERY_H__
#define __SERVICE_DISOVERY_H__
#include "UUID.h"
#include "Gap.h"
#include "GattAttribute.h"
class DiscoveredService;
class DiscoveredCharacteristic;
class ServiceDiscovery {
public:
/*
* Exposed application callback types.
*/
/**
* Callback type for when a matching service is found during service-
* discovery. The receiving function is passed in a pointer to a
* DiscoveredService object, which will remain valid for the lifetime of the
* callback. Memory for this object is owned by the BLE_API eventing
* framework. The application can safely make a persistent shallow-copy of
* this object to work with the service beyond the callback.
*/
typedef FunctionPointerWithContext<const DiscoveredService *> ServiceCallback_t;
/**
* Callback type for when a matching characteristic is found during service-
* discovery. The receiving function is passed in a pointer to a
* DiscoveredCharacteristic object, which will remain valid for the lifetime
* of the callback. Memory for this object is owned by the BLE_API eventing
* framework. The application can safely make a persistent shallow-copy of
* this object to work with the characteristic beyond the callback.
*/
typedef FunctionPointerWithContext<const DiscoveredCharacteristic *> CharacteristicCallback_t;
/**
* Callback type for when serviceDiscovery terminates.
*/
typedef FunctionPointerWithContext<Gap::Handle_t> TerminationCallback_t;
public:
/**
* Launch service discovery. Once launched, service discovery will remain
* active with callbacks being issued back into the application for matching
* services or characteristics. isActive() can be used to determine status, and
* a termination callback (if set up) will be invoked at the end. Service
* discovery can be terminated prematurely, if needed, using terminate().
*
* @param connectionHandle
* Handle for the connection with the peer.
* @param sc
* This is the application callback for a matching service. Taken as
* NULL by default. Note: service discovery may still be active
* when this callback is issued; calling asynchronous BLE-stack
* APIs from within this application callback might cause the
* stack to abort service discovery. If this becomes an issue, it
* may be better to make a local copy of the discoveredService and
* wait for service discovery to terminate before operating on the
* service.
* @param cc
* This is the application callback for a matching characteristic.
* Taken as NULL by default. Note: service discovery may still be
* active when this callback is issued; calling asynchronous
* BLE-stack APIs from within this application callback might cause
* the stack to abort service discovery. If this becomes an issue,
* it may be better to make a local copy of the discoveredCharacteristic
* and wait for service discovery to terminate before operating on the
* characteristic.
* @param matchingServiceUUID
* UUID-based filter for specifying a service in which the application is
* interested. By default it is set as the wildcard UUID_UNKNOWN,
* in which case it matches all services. If characteristic-UUID
* filter (below) is set to the wildcard value, then a service
* callback will be invoked for the matching service (or for every
* service if the service filter is a wildcard).
* @param matchingCharacteristicUUIDIn
* UUID-based filter for specifying a characteristic in which the application
* is interested. By default it is set as the wildcard UUID_UKNOWN
* to match against any characteristic. If both service-UUID
* filter and characteristic-UUID filter are used with non-wildcard
* values, then only a single characteristic callback is
* invoked for the matching characteristic.
*
* @note Using wildcard values for both service-UUID and characteristic-
* UUID will result in complete service discovery: callbacks being
* called for every service and characteristic.
*
* @note Providing NULL for the characteristic callback will result in
* characteristic discovery being skipped for each matching
* service. This allows for an inexpensive method to discover only
* services.
*
* @return
* BLE_ERROR_NONE if service discovery is launched successfully; else an appropriate error.
*/
virtual ble_error_t launch(Gap::Handle_t connectionHandle,
ServiceCallback_t sc = NULL,
CharacteristicCallback_t cc = NULL,
const UUID &matchingServiceUUID = UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN),
const UUID &matchingCharacteristicUUIDIn = UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN)) = 0;
/**
* Check whether service-discovery is currently active.
*/
virtual bool isActive(void) const = 0;
/**
* Terminate an ongoing service discovery. This should result in an
* invocation of the TerminationCallback if service discovery is active.
*/
virtual void terminate(void) = 0;
/**
* Set up a callback to be invoked when service discovery is terminated.
*/
virtual void onTermination(TerminationCallback_t callback) = 0;
/**
* Clear all ServiceDiscovery state of the associated object.
*
* This function is meant to be overridden in the platform-specific
* sub-class. Nevertheless, the sub-class is only expected to reset its
* state and not the data held in ServiceDiscovery members. This shall be
* achieved by a call to ServiceDiscovery::reset() from the sub-class'
* reset() implementation.
*
* @return BLE_ERROR_NONE on success.
*/
virtual ble_error_t reset(void) {
connHandle = 0;
matchingServiceUUID = UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN);
serviceCallback = NULL;
matchingCharacteristicUUID = UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN);
characteristicCallback = NULL;
return BLE_ERROR_NONE;
}
protected:
/**
* Connection handle as provided by the SoftDevice.
*/
Gap::Handle_t connHandle;
/**
* UUID-based filter that specifies the service that the application is
* interested in.
*/
UUID matchingServiceUUID;
/**
* The registered callback handle for when a matching service is found
* during service-discovery.
*/
ServiceCallback_t serviceCallback;
/**
* UUID-based filter that specifies the characteristic that the
* application is interested in.
*/
UUID matchingCharacteristicUUID;
/**
* The registered callback handler for when a matching characteristic is
* found during service-discovery.
*/
CharacteristicCallback_t characteristicCallback;
};
#endif /* ifndef __SERVICE_DISOVERY_H__ */