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

690 lines
26 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 __GATT_SERVER_H__
#define __GATT_SERVER_H__
#include "Gap.h"
#include "GattService.h"
#include "GattAttribute.h"
#include "GattServerEvents.h"
#include "GattCallbackParamTypes.h"
#include "CallChainOfFunctionPointersWithContext.h"
class GattServer {
public:
/**
* Type for the registered callbacks added to the data sent callchain.
* Refer to GattServer::onDataSent().
*/
typedef FunctionPointerWithContext<unsigned> DataSentCallback_t;
/**
* Type for the data sent event callchain. Refer to GattServer::onDataSent().
*/
typedef CallChainOfFunctionPointersWithContext<unsigned> DataSentCallbackChain_t;
/**
* Type for the registered callbacks added to the data written callchain.
* Refer to GattServer::onDataWritten().
*/
typedef FunctionPointerWithContext<const GattWriteCallbackParams*> DataWrittenCallback_t;
/**
* Type for the data written event callchain. Refer to GattServer::onDataWritten().
*/
typedef CallChainOfFunctionPointersWithContext<const GattWriteCallbackParams*> DataWrittenCallbackChain_t;
/**
* Type for the registered callbacks added to the data read callchain.
* Refer to GattServer::onDataRead().
*/
typedef FunctionPointerWithContext<const GattReadCallbackParams*> DataReadCallback_t;
/**
* Type for the data read event callchain. Refer to GattServer::onDataRead().
*/
typedef CallChainOfFunctionPointersWithContext<const GattReadCallbackParams *> DataReadCallbackChain_t;
/**
* Type for the registered callbacks added to the shutdown callchain.
* Refer to GattServer::onShutdown().
*/
typedef FunctionPointerWithContext<const GattServer *> GattServerShutdownCallback_t;
/**
* Type for the shutdown event callchain. Refer to GattServer::onShutdown().
*/
typedef CallChainOfFunctionPointersWithContext<const GattServer *> GattServerShutdownCallbackChain_t;
/**
* Type for the registered callback for various events. Refer to
* GattServer::onUpdatesEnabled(), GattServer::onUpdateDisabled() and
* GattServer::onConfirmationReceived().
*/
typedef FunctionPointerWithContext<GattAttribute::Handle_t> EventCallback_t;
protected:
/**
* Construct a GattServer instance.
*/
GattServer() :
serviceCount(0),
characteristicCount(0),
dataSentCallChain(),
dataWrittenCallChain(),
dataReadCallChain(),
updatesEnabledCallback(NULL),
updatesDisabledCallback(NULL),
confirmationReceivedCallback(NULL) {
/* empty */
}
/*
* The following functions are meant to be overridden in the platform-specific sub-class.
*/
public:
/**
* Add a service declaration to the local server ATT table. Also add the
* characteristics contained within.
*
* @param[in] service
* The service to be added.
*
* @return BLE_ERROR_NONE if the service was successfully added.
*/
virtual ble_error_t addService(GattService &service) {
/* Avoid compiler warnings about unused variables. */
(void)service;
return BLE_ERROR_NOT_IMPLEMENTED; /* Requesting action from porters: override this API if this capability is supported. */
}
/**
* Read the value of a characteristic from the local GATT server.
*
* @param[in] attributeHandle
* Attribute handle for the value attribute of the characteristic.
* @param[out] buffer
* A buffer to hold the value being read.
* @param[in,out] lengthP
* Length of the buffer being supplied. If the attribute
* value is longer than the size of the supplied buffer,
* this variable will hold upon return the total attribute value length
* (excluding offset). The application may use this
* information to allocate a suitable buffer size.
*
* @return BLE_ERROR_NONE if a value was read successfully into the buffer.
*/
virtual ble_error_t read(GattAttribute::Handle_t attributeHandle, uint8_t buffer[], uint16_t *lengthP) {
/* Avoid compiler warnings about unused variables. */
(void)attributeHandle;
(void)buffer;
(void)lengthP;
return BLE_ERROR_NOT_IMPLEMENTED; /* Requesting action from porters: override this API if this capability is supported. */
}
/**
* Read the value of a characteristic from the local GATT server.
*
* @param[in] connectionHandle
* Connection handle.
* @param[in] attributeHandle
* Attribute handle for the value attribute of the characteristic.
* @param[out] buffer
* A buffer to hold the value being read.
* @param[in,out] lengthP
* Length of the buffer being supplied. If the attribute
* value is longer than the size of the supplied buffer,
* this variable will hold upon return the total attribute value length
* (excluding offset). The application may use this
* information to allocate a suitable buffer size.
*
* @return BLE_ERROR_NONE if a value was read successfully into the buffer.
*
* @note This API is a version of the above, with an additional connection handle
* parameter to allow fetches for connection-specific multivalued
* attributes (such as the CCCDs).
*/
virtual ble_error_t read(Gap::Handle_t connectionHandle, GattAttribute::Handle_t attributeHandle, uint8_t *buffer, uint16_t *lengthP) {
/* Avoid compiler warnings about unused variables. */
(void)connectionHandle;
(void)attributeHandle;
(void)buffer;
(void)lengthP;
return BLE_ERROR_NOT_IMPLEMENTED; /* Requesting action from porters: override this API if this capability is supported. */
}
/**
* Update the value of a characteristic on the local GATT server.
*
* @param[in] attributeHandle
* Handle for the value attribute of the characteristic.
* @param[in] value
* A pointer to a buffer holding the new value.
* @param[in] size
* Size of the new value (in bytes).
* @param[in] localOnly
* Should this update be kept on the local
* GATT server regardless of the state of the
* notify/indicate flag in the CCCD for this
* Characteristic? If set to true, no notification
* or indication is generated.
*
* @return BLE_ERROR_NONE if we have successfully set the value of the attribute.
*/
virtual ble_error_t write(GattAttribute::Handle_t attributeHandle, const uint8_t *value, uint16_t size, bool localOnly = false) {
/* Avoid compiler warnings about unused variables. */
(void)attributeHandle;
(void)value;
(void)size;
(void)localOnly;
return BLE_ERROR_NOT_IMPLEMENTED; /* Requesting action from porters: override this API if this capability is supported. */
}
/**
* Update the value of a characteristic on the local GATT server. A version
* of the same as the above, with a connection handle parameter to allow updates
* for connection-specific multivalued attributes (such as the CCCDs).
*
* @param[in] connectionHandle
* Connection handle.
* @param[in] attributeHandle
* Handle for the value attribute of the characteristic.
* @param[in] value
* A pointer to a buffer holding the new value.
* @param[in] size
* Size of the new value (in bytes).
* @param[in] localOnly
* Should this update be kept on the local
* GattServer regardless of the state of the
* notify/indicate flag in the CCCD for this
* Characteristic? If set to true, no notification
* or indication is generated.
*
* @return BLE_ERROR_NONE if we have successfully set the value of the attribute.
*/
virtual ble_error_t write(Gap::Handle_t connectionHandle, GattAttribute::Handle_t attributeHandle, const uint8_t *value, uint16_t size, bool localOnly = false) {
/* Avoid compiler warnings about unused variables. */
(void)connectionHandle;
(void)attributeHandle;
(void)value;
(void)size;
(void)localOnly;
return BLE_ERROR_NOT_IMPLEMENTED; /* Requesting action from porters: override this API if this capability is supported. */
}
/**
* Determine the updates-enabled status (notification or indication) for the current connection from a characteristic's CCCD.
*
* @param[in] characteristic
* The characteristic.
* @param[out] enabledP
* Upon return, *enabledP is true if updates are enabled, else false.
*
* @return BLE_ERROR_NONE if the connection and handle are found. False otherwise.
*/
virtual ble_error_t areUpdatesEnabled(const GattCharacteristic &characteristic, bool *enabledP) {
/* Avoid compiler warnings about unused variables. */
(void)characteristic;
(void)enabledP;
return BLE_ERROR_NOT_IMPLEMENTED; /* Requesting action from porters: override this API if this capability is supported. */
}
/**
* Determine the connection-specific updates-enabled status (notification or indication) from a characteristic's CCCD.
*
* @param[in] connectionHandle
* The connection handle.
* @param[in] characteristic
* The characteristic.
* @param[out] enabledP
* Upon return, *enabledP is true if updates are enabled, else false.
*
* @return BLE_ERROR_NONE if the connection and handle are found. False otherwise.
*/
virtual ble_error_t areUpdatesEnabled(Gap::Handle_t connectionHandle, const GattCharacteristic &characteristic, bool *enabledP) {
/* Avoid compiler warnings about unused variables. */
(void)connectionHandle;
(void)characteristic;
(void)enabledP;
return BLE_ERROR_NOT_IMPLEMENTED; /* Requesting action from porters: override this API if this capability is supported. */
}
/**
* A virtual function to allow underlying stacks to indicate if they support
* onDataRead(). It should be overridden to return true as applicable.
*
* @return true if onDataRead is supported, false otherwise.
*/
virtual bool isOnDataReadAvailable() const {
return false; /* Requesting action from porters: override this API if this capability is supported. */
}
/*
* APIs with non-virtual implementations.
*/
public:
/**
* Add a callback for the GATT event DATA_SENT (which is triggered when
* updates are sent out by GATT in the form of notifications).
*
* @param[in] callback
* Event handler being registered.
*
* @note It is possible to chain together multiple onDataSent callbacks
* (potentially from different modules of an application) to receive updates
* to characteristics.
*
* @note It is also possible to set up a callback into a member function of
* some object.
*/
void onDataSent(const DataSentCallback_t& callback) {
dataSentCallChain.add(callback);
}
/**
* Same as GattServer::onDataSent(), but allows the possibility to add an object
* reference and member function as handler for DATA_SENT event
* callbacks.
*
* @param[in] objPtr
* Pointer to the object of a class defining the member callback
* function (@p memberPtr).
* @param[in] memberPtr
* The member callback (within the context of an object) to be
* invoked.
*/
template <typename T>
void onDataSent(T *objPtr, void (T::*memberPtr)(unsigned count)) {
dataSentCallChain.add(objPtr, memberPtr);
}
/**
* @brief Provide access to the callchain of DATA_SENT event callbacks.
*
* @return A reference to the DATA_SENT event callback chain.
*/
DataSentCallbackChain_t& onDataSent() {
return dataSentCallChain;
}
/**
* Set up a callback for when an attribute has its value updated by or at the
* connected peer. For a peripheral, this callback is triggered when the local
* GATT server has an attribute updated by a write command from the peer.
* For a central, this callback is triggered when a response is received for
* a write request.
*
* @param[in] callback
* Event handler being registered.
*
* @note It is possible to chain together multiple onDataWritten callbacks
* (potentially from different modules of an application) to receive updates
* to characteristics. Many services, such as DFU and UART, add their own
* onDataWritten callbacks behind the scenes to trap interesting events.
*
* @note It is also possible to set up a callback into a member function of
* some object.
*
* @note It is possible to unregister a callback using onDataWritten().detach(callback)
*/
void onDataWritten(const DataWrittenCallback_t& callback) {
dataWrittenCallChain.add(callback);
}
/**
* Same as GattServer::onDataWritten(), but allows the possibility to add an object
* reference and member function as handler for data written event
* callbacks.
*
* @param[in] objPtr
* Pointer to the object of a class defining the member callback
* function (@p memberPtr).
* @param[in] memberPtr
* The member callback (within the context of an object) to be
* invoked.
*/
template <typename T>
void onDataWritten(T *objPtr, void (T::*memberPtr)(const GattWriteCallbackParams *context)) {
dataWrittenCallChain.add(objPtr, memberPtr);
}
/**
* @brief Provide access to the callchain of data written event callbacks.
*
* @return A reference to the data written event callbacks chain.
*
* @note It is possible to register callbacks using onDataWritten().add(callback).
*
* @note It is possible to unregister callbacks using onDataWritten().detach(callback).
*/
DataWrittenCallbackChain_t& onDataWritten() {
return dataWrittenCallChain;
}
/**
* Setup a callback to be invoked on the peripheral when an attribute is
* being read by a remote client.
*
* @param[in] callback
* Event handler being registered.
*
* @return BLE_ERROR_NOT_IMPLEMENTED if this functionality isn't available;
* else BLE_ERROR_NONE.
*
* @note This functionality may not be available on all underlying stacks.
* You could use GattCharacteristic::setReadAuthorizationCallback() as an
* alternative. Refer to isOnDataReadAvailable().
*
* @note It is possible to chain together multiple onDataRead callbacks
* (potentially from different modules of an application) to receive updates
* to characteristics. Services may add their own onDataRead callbacks
* behind the scenes to trap interesting events.
*
* @note It is also possible to set up a callback into a member function of
* some object.
*
* @note It is possible to unregister a callback using onDataRead().detach(callback).
*/
ble_error_t onDataRead(const DataReadCallback_t& callback) {
if (!isOnDataReadAvailable()) {
return BLE_ERROR_NOT_IMPLEMENTED;
}
dataReadCallChain.add(callback);
return BLE_ERROR_NONE;
}
/**
* Same as GattServer::onDataRead(), but allows the possibility to add an object
* reference and member function as handler for data read event
* callbacks.
*
* @param[in] objPtr
* Pointer to the object of a class defining the member callback
* function (@p memberPtr).
* @param[in] memberPtr
* The member callback (within the context of an object) to be
* invoked.
*/
template <typename T>
ble_error_t onDataRead(T *objPtr, void (T::*memberPtr)(const GattReadCallbackParams *context)) {
if (!isOnDataReadAvailable()) {
return BLE_ERROR_NOT_IMPLEMENTED;
}
dataReadCallChain.add(objPtr, memberPtr);
return BLE_ERROR_NONE;
}
/**
* @brief Provide access to the callchain of data read event callbacks.
*
* @return A reference to the data read event callbacks chain.
*
* @note It is possible to register callbacks using onDataRead().add(callback).
*
* @note It is possible to unregister callbacks using onDataRead().detach(callback).
*/
DataReadCallbackChain_t& onDataRead() {
return dataReadCallChain;
}
/**
* Setup a callback to be invoked to notify the user application that the
* GattServer instance is about to shutdown (possibly as a result of a call
* to BLE::shutdown()).
*
* @param[in] callback
* Event handler being registered.
*
* @note It is possible to chain together multiple onShutdown callbacks
* (potentially from different modules of an application) to be notified
* before the GattServer is shutdown.
*
* @note It is also possible to set up a callback into a member function of
* some object.
*
* @note It is possible to unregister a callback using onShutdown().detach(callback)
*/
void onShutdown(const GattServerShutdownCallback_t& callback) {
shutdownCallChain.add(callback);
}
/**
* Same as GattServer::onShutdown(), but allows the possibility to add an object
* reference and member function as handler for shutdown event
* callbacks.
*
* @param[in] objPtr
* Pointer to the object of a class defining the member callback
* function (@p memberPtr).
* @param[in] memberPtr
* The member callback (within the context of an object) to be
* invoked.
*/
template <typename T>
void onShutdown(T *objPtr, void (T::*memberPtr)(const GattServer *)) {
shutdownCallChain.add(objPtr, memberPtr);
}
/**
* @brief Provide access to the callchain of shutdown event callbacks.
*
* @return A reference to the shutdown event callbacks chain.
*
* @note It is possible to register callbacks using onShutdown().add(callback).
*
* @note It is possible to unregister callbacks using onShutdown().detach(callback).
*/
GattServerShutdownCallbackChain_t& onShutdown() {
return shutdownCallChain;
}
/**
* Set up a callback for when notifications or indications are enabled for a
* characteristic on the local GATT server.
*
* @param[in] callback
* Event handler being registered.
*/
void onUpdatesEnabled(EventCallback_t callback) {
updatesEnabledCallback = callback;
}
/**
* Set up a callback for when notifications or indications are disabled for a
* characteristic on the local GATT server.
*
* @param[in] callback
* Event handler being registered.
*/
void onUpdatesDisabled(EventCallback_t callback) {
updatesDisabledCallback = callback;
}
/**
* Set up a callback for when the GATT server receives a response for an
* indication event sent previously.
*
* @param[in] callback
* Event handler being registered.
*/
void onConfirmationReceived(EventCallback_t callback) {
confirmationReceivedCallback = callback;
}
/* Entry points for the underlying stack to report events back to the user. */
protected:
/**
* Helper function that notifies all registered handlers of an occurrence
* of a data written event. This function is meant to be called from the
* BLE stack specific implementation when a data written event occurs.
*
* @param[in] params
* The data written parameters passed to the registered
* handlers.
*/
void handleDataWrittenEvent(const GattWriteCallbackParams *params) {
dataWrittenCallChain.call(params);
}
/**
* Helper function that notifies all registered handlers of an occurrence
* of a data read event. This function is meant to be called from the
* BLE stack specific implementation when a data read event occurs.
*
* @param[in] params
* The data read parameters passed to the registered
* handlers.
*/
void handleDataReadEvent(const GattReadCallbackParams *params) {
dataReadCallChain.call(params);
}
/**
* Helper function that notifies the registered handler of an occurrence
* of updates enabled, updates disabled and confirmation received events.
* This function is meant to be called from the BLE stack specific
* implementation when any of these events occurs.
*
* @param[in] type
* The type of event that occurred.
* @param[in] attributeHandle
* The handle of the attribute that was modified.
*/
void handleEvent(GattServerEvents::gattEvent_e type, GattAttribute::Handle_t attributeHandle) {
switch (type) {
case GattServerEvents::GATT_EVENT_UPDATES_ENABLED:
if (updatesEnabledCallback) {
updatesEnabledCallback(attributeHandle);
}
break;
case GattServerEvents::GATT_EVENT_UPDATES_DISABLED:
if (updatesDisabledCallback) {
updatesDisabledCallback(attributeHandle);
}
break;
case GattServerEvents::GATT_EVENT_CONFIRMATION_RECEIVED:
if (confirmationReceivedCallback) {
confirmationReceivedCallback(attributeHandle);
}
break;
default:
break;
}
}
/**
* Helper function that notifies all registered handlers of an occurrence
* of a data sent event. This function is meant to be called from the
* BLE stack specific implementation when a data sent event occurs.
*
* @param[in] count
* Number of packets sent.
*/
void handleDataSentEvent(unsigned count) {
dataSentCallChain.call(count);
}
public:
/**
* Notify all registered onShutdown callbacks that the GattServer is
* about to be shutdown and clear all GattServer 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 GattServer members. This shall be achieved
* by a call to GattServer::reset() from the sub-class' reset()
* implementation.
*
* @return BLE_ERROR_NONE on success.
*/
virtual ble_error_t reset(void) {
/* Notify that the instance is about to shutdown */
shutdownCallChain.call(this);
shutdownCallChain.clear();
serviceCount = 0;
characteristicCount = 0;
dataSentCallChain.clear();
dataWrittenCallChain.clear();
dataReadCallChain.clear();
updatesEnabledCallback = NULL;
updatesDisabledCallback = NULL;
confirmationReceivedCallback = NULL;
return BLE_ERROR_NONE;
}
protected:
/**
* The total number of services added to the ATT table.
*/
uint8_t serviceCount;
/**
* The total number of characteristics added to the ATT table.
*/
uint8_t characteristicCount;
private:
/**
* Callchain containing all registered callback handlers for data sent
* events.
*/
DataSentCallbackChain_t dataSentCallChain;
/**
* Callchain containing all registered callback handlers for data written
* events.
*/
DataWrittenCallbackChain_t dataWrittenCallChain;
/**
* Callchain containing all registered callback handlers for data read
* events.
*/
DataReadCallbackChain_t dataReadCallChain;
/**
* Callchain containing all registered callback handlers for shutdown
* events.
*/
GattServerShutdownCallbackChain_t shutdownCallChain;
/**
* The registered callback handler for updates enabled events.
*/
EventCallback_t updatesEnabledCallback;
/**
* The registered callback handler for updates disabled events.
*/
EventCallback_t updatesDisabledCallback;
/**
* The registered callback handler for confirmation received events.
*/
EventCallback_t confirmationReceivedCallback;
private:
/* Disallow copy and assignment. */
GattServer(const GattServer &);
GattServer& operator=(const GattServer &);
};
#endif /* ifndef __GATT_SERVER_H__ */