Simon Cooksey
Pinned to some recent date
Diff: features/FEATURE_BLE/ble/GattClient.h
- Revision:
- 0:fb7af294d5d9
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/features/FEATURE_BLE/ble/GattClient.h Thu Nov 17 16:43:53 2016 +0000
@@ -0,0 +1,626 @@
+/* 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_CLIENT_H__
+#define __GATT_CLIENT_H__
+
+#include "Gap.h"
+#include "GattAttribute.h"
+#include "ServiceDiscovery.h"
+#include "CharacteristicDescriptorDiscovery.h"
+
+#include "GattCallbackParamTypes.h"
+
+#include "CallChainOfFunctionPointersWithContext.h"
+
+class GattClient {
+public:
+ /**
+ * Type for the registered callbacks added to the data read callchain.
+ * Refer to GattClient::onDataRead().
+ */
+ typedef FunctionPointerWithContext<const GattReadCallbackParams*> ReadCallback_t;
+ /**
+ * Type for the data read event callchain. Refer to GattClient::onDataRead().
+ */
+ typedef CallChainOfFunctionPointersWithContext<const GattReadCallbackParams*> ReadCallbackChain_t;
+
+ /**
+ * Enumerator for write operations.
+ */
+ enum WriteOp_t {
+ GATT_OP_WRITE_REQ = 0x01, /**< Write request. */
+ GATT_OP_WRITE_CMD = 0x02, /**< Write command. */
+ };
+
+ /**
+ * Type for the registered callbacks added to the data write callchain.
+ * Refer to GattClient::onDataWrite().
+ */
+ typedef FunctionPointerWithContext<const GattWriteCallbackParams*> WriteCallback_t;
+ /**
+ * Type for the data write event callchain. Refer to GattClient::onDataWrite().
+ */
+ typedef CallChainOfFunctionPointersWithContext<const GattWriteCallbackParams*> WriteCallbackChain_t;
+
+ /**
+ * Type for the registered callbacks added to the update event callchain.
+ * Refer to GattClient::onHVX().
+ */
+ typedef FunctionPointerWithContext<const GattHVXCallbackParams*> HVXCallback_t;
+ /**
+ * Type for the update event callchain. Refer to GattClient::onHVX().
+ */
+ typedef CallChainOfFunctionPointersWithContext<const GattHVXCallbackParams*> HVXCallbackChain_t;
+
+ /**
+ * Type for the registered callbacks added to the shutdown callchain.
+ * Refer to GattClient::onShutdown().
+ */
+ typedef FunctionPointerWithContext<const GattClient *> GattClientShutdownCallback_t;
+ /**
+ * Type for the shutdown event callchain. Refer to GattClient::onShutown().
+ */
+ typedef CallChainOfFunctionPointersWithContext<const GattClient *> GattClientShutdownCallbackChain_t;
+
+ /*
+ * The following functions are meant to be overridden in the platform-specific sub-class.
+ */
+public:
+ /**
+ * Launch service discovery. Once launched, application callbacks will be
+ * invoked for matching services or characteristics. isServiceDiscoveryActive()
+ * can be used to determine status, and a termination callback (if one was set up)
+ * will be invoked at the end. Service discovery can be terminated prematurely,
+ * if needed, using terminateServiceDiscovery().
+ *
+ * @param[in] connectionHandle
+ * Handle for the connection with the peer.
+ * @param[in] 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[in] 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[in] 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[in] matchingCharacteristicUUIDIn
+ * UUID-based filter for specifying 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 launchServiceDiscovery(Gap::Handle_t connectionHandle,
+ ServiceDiscovery::ServiceCallback_t sc = NULL,
+ ServiceDiscovery::CharacteristicCallback_t cc = NULL,
+ const UUID &matchingServiceUUID = UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN),
+ const UUID &matchingCharacteristicUUIDIn = UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN)) {
+ /* Avoid compiler warnings about unused variables. */
+ (void)connectionHandle;
+ (void)sc;
+ (void)cc;
+ (void)matchingServiceUUID;
+ (void)matchingCharacteristicUUIDIn;
+
+ return BLE_ERROR_NOT_IMPLEMENTED; /* Requesting action from porters: override this API if this capability is supported. */
+ }
+
+ /**
+ * Launch service discovery for services. Once launched, service discovery will remain
+ * active with service-callbacks being issued back into the application for matching
+ * services. isServiceDiscoveryActive() 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 terminateServiceDiscovery().
+ *
+ * @param[in] connectionHandle
+ * Handle for the connection with the peer.
+ * @param[in] callback
+ * This is the application callback for a matching service.
+ * 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[in] 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.
+ *
+ * @return
+ * BLE_ERROR_NONE if service discovery is launched successfully; else an appropriate error.
+ */
+ virtual ble_error_t discoverServices(Gap::Handle_t connectionHandle,
+ ServiceDiscovery::ServiceCallback_t callback,
+ const UUID &matchingServiceUUID = UUID::ShortUUIDBytes_t(BLE_UUID_UNKNOWN)) {
+ return launchServiceDiscovery(connectionHandle, callback, NULL, matchingServiceUUID); /* We take advantage of the property
+ * that 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. Porters are free to override this. */
+ }
+
+ /**
+ * Launch service discovery for services. Once launched, service discovery will remain
+ * active with service-callbacks being issued back into the application for matching
+ * services. isServiceDiscoveryActive() 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 terminateServiceDiscovery().
+ *
+ * @param[in] connectionHandle
+ * Handle for the connection with the peer.
+ * @param[in] callback
+ * This is the application callback for a matching service.
+ * 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[in] startHandle, endHandle
+ * Handle range within which to limit the search.
+ *
+ * @return
+ * BLE_ERROR_NONE if service discovery is launched successfully; else an appropriate error.
+ */
+ virtual ble_error_t discoverServices(Gap::Handle_t connectionHandle,
+ ServiceDiscovery::ServiceCallback_t callback,
+ GattAttribute::Handle_t startHandle,
+ GattAttribute::Handle_t endHandle) {
+ /* Avoid compiler warnings about unused variables. */
+ (void)connectionHandle;
+ (void)callback;
+ (void)startHandle;
+ (void)endHandle;
+
+ return BLE_ERROR_NOT_IMPLEMENTED; /* Requesting action from porters: override this API if this capability is supported. */
+ }
+
+ /**
+ * Check if service-discovery is currently active.
+ *
+ * @return true if service-discovery is active, false otherwise.
+ */
+ virtual bool isServiceDiscoveryActive(void) const {
+ return false; /* Requesting action from porters: override this API if this capability is supported. */
+ }
+
+ /**
+ * Terminate an ongoing service discovery. This should result in an
+ * invocation of TerminationCallback if service-discovery is active.
+ */
+ virtual void terminateServiceDiscovery(void) {
+ /* Requesting action from porters: override this API if this capability is supported. */
+ }
+
+ /**
+ * Initiate a GATT Client read procedure by attribute-handle.
+ *
+ * @param[in] connHandle
+ * Handle for the connection with the peer.
+ * @param[in] attributeHandle
+ * Handle of the attribute to read data from.
+ * @param[in] offset
+ * The offset from the start of the attribute value to be read.
+ *
+ * @return
+ * BLE_ERROR_NONE if read procedure was successfully started.
+ */
+ virtual ble_error_t read(Gap::Handle_t connHandle, GattAttribute::Handle_t attributeHandle, uint16_t offset) const {
+ /* Avoid compiler warnings about unused variables. */
+ (void)connHandle;
+ (void)attributeHandle;
+ (void)offset;
+
+ return BLE_ERROR_NOT_IMPLEMENTED; /* Requesting action from porters: override this API if this capability is supported. */
+ }
+
+ /**
+ * Initiate a GATT Client write procedure.
+ *
+ * @param[in] cmd
+ * Command can be either a write-request (which generates a
+ * matching response from the peripheral), or a write-command
+ * (which doesn't require the connected peer to respond).
+ * @param[in] connHandle
+ * Connection handle.
+ * @param[in] attributeHandle
+ * Handle for the target attribtue on the remote GATT server.
+ * @param[in] length
+ * Length of the new value.
+ * @param[in] value
+ * New value being written.
+ *
+ * @return
+ * BLE_ERROR_NONE if write procedure was successfully started.
+ */
+ virtual ble_error_t write(GattClient::WriteOp_t cmd,
+ Gap::Handle_t connHandle,
+ GattAttribute::Handle_t attributeHandle,
+ size_t length,
+ const uint8_t *value) const {
+ /* Avoid compiler warnings about unused variables. */
+ (void)cmd;
+ (void)connHandle;
+ (void)attributeHandle;
+ (void)length;
+ (void)value;
+
+ return BLE_ERROR_NOT_IMPLEMENTED; /* Requesting action from porters: override this API if this capability is supported. */
+ }
+
+ /* Event callback handlers. */
+public:
+ /**
+ * Set up a callback for read response events.
+ *
+ * @param[in] callback
+ * Event handler being registered.
+ *
+ * @note It is possible to chain together multiple onDataRead callbacks
+ * (potentially from different modules of an application).
+ *
+ * @note It is possible to unregister a callback using
+ * onDataRead().detach(callbackToRemove).
+ */
+ void onDataRead(ReadCallback_t callback) {
+ onDataReadCallbackChain.add(callback);
+ }
+
+ /**
+ * @brief Provide access to the callchain of read event callbacks.
+ *
+ * @return A reference to the read event callback chain.
+ *
+ * @note It is possible to register callbacks using onDataRead().add(callback).
+ *
+ * @note It is possible to unregister callbacks using onDataRead().detach(callback).
+ */
+ ReadCallbackChain_t& onDataRead() {
+ return onDataReadCallbackChain;
+ }
+
+ /**
+ * Set up a callback for write response events.
+ *
+ * @param[in] callback
+ * Event handler being registered.
+ *
+ * @note It is possible to remove registered callbacks using
+ * onDataWritten().detach(callbackToRemove).
+ *
+ * @note Write commands (issued using writeWoResponse) don't generate a response.
+ */
+ void onDataWritten(WriteCallback_t callback) {
+ onDataWriteCallbackChain.add(callback);
+ }
+
+ /**
+ * @brief Provide access to the callchain of data written callbacks.
+ *
+ * @return A reference to the data written callbacks chain.
+ *
+ * @note It is possible to register callbacks using onDataWritten().add(callback).
+ *
+ * @note It is possible to unregister callbacks using onDataWritten().detach(callback).
+ */
+ WriteCallbackChain_t& onDataWritten() {
+ return onDataWriteCallbackChain;
+ }
+
+ /**
+ * Set up a callback for write response events.
+ *
+ * @param[in] callback
+ * Event handler being registered.
+ *
+ * @note Write commands (issued using writeWoResponse) don't generate a response.
+ *
+ * @deprecated Please use GattServer::onDataWritten() instead.
+ */
+ void onDataWrite(WriteCallback_t callback) {
+ onDataWritten(callback);
+ }
+
+ /**
+ * Set up a callback for when serviceDiscovery terminates.
+ *
+ * @param[in] callback
+ * Event handler being registered.
+ */
+ virtual void onServiceDiscoveryTermination(ServiceDiscovery::TerminationCallback_t callback) {
+ (void)callback; /* Avoid compiler warnings about ununsed variables. */
+
+ /* Requesting action from porters: override this API if this capability is supported. */
+ }
+
+ /**
+ * @brief Launch discovery of descriptors for a given characteristic.
+ *
+ * @details This function will discover all descriptors available for a
+ * specific characteristic.
+ *
+ * @param[in] characteristic
+ * The characteristic targeted by this discovery procedure.
+ * @param[in] discoveryCallback
+ * User function called each time a descriptor is found during
+ * the procedure.
+ * @param[in] terminationCallback
+ * User provided function which will be called once the
+ * discovery procedure is terminating. This will get called
+ * when all the descriptors have been discovered or if an
+ * error occur during the discovery procedure.
+ *
+ * @return
+ * BLE_ERROR_NONE if characteristic descriptor discovery is launched
+ * successfully; else an appropriate error.
+ */
+ virtual ble_error_t discoverCharacteristicDescriptors(
+ const DiscoveredCharacteristic& characteristic,
+ const CharacteristicDescriptorDiscovery::DiscoveryCallback_t& discoveryCallback,
+ const CharacteristicDescriptorDiscovery::TerminationCallback_t& terminationCallback) {
+ (void) characteristic;
+ (void) discoveryCallback;
+ (void) terminationCallback;
+ /* Requesting action from porter(s): override this API if this capability is supported. */
+ return BLE_ERROR_NOT_IMPLEMENTED;
+ }
+
+ /**
+ * @brief Indicate if the discovery of characteristic descriptors is active
+ * for a given characteristic or not.
+ *
+ * @param[in] characteristic
+ * The characteristic concerned by the descriptors discovery.
+ *
+ * @return true if a descriptors discovery is active for the characteristic
+ * in input; otherwise false.
+ */
+ virtual bool isCharacteristicDescriptorDiscoveryActive(const DiscoveredCharacteristic& characteristic) const
+ {
+ (void) characteristic;
+ return false; /* Requesting action from porter(s): override this API if this capability is supported. */
+ }
+
+ /**
+ * @brief Terminate an ongoing characteristic descriptor discovery.
+ *
+ * @details This should result in an invocation of the TerminationCallback if
+ * the characteristic descriptor discovery is active.
+ *
+ * @param[in] characteristic
+ * The characteristic on which the running descriptors
+ * discovery should be stopped.
+ */
+ virtual void terminateCharacteristicDescriptorDiscovery(const DiscoveredCharacteristic& characteristic) {
+ /* Requesting action from porter(s): override this API if this capability is supported. */
+ (void) characteristic;
+ }
+
+ /**
+ * Set up a callback for when the GATT Client receives an update event
+ * corresponding to a change in the value of a characteristic on the remote
+ * GATT Server.
+ *
+ * @note It is possible to unregister callbacks using
+ * onHVX().detach(callbackToRemove).
+ */
+ void onHVX(HVXCallback_t callback) {
+ onHVXCallbackChain.add(callback);
+ }
+
+ /**
+ * Setup a callback to be invoked to notify the user application that the
+ * GattClient 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 GattClient 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 GattClientShutdownCallback_t& callback) {
+ shutdownCallChain.add(callback);
+ }
+
+ /**
+ * Same as GattClient::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 GattClient *)) {
+ 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).
+ */
+ GattClientShutdownCallbackChain_t& onShutdown() {
+ return shutdownCallChain;
+ }
+
+ /**
+ * @brief provide access to the callchain of HVX callbacks.
+ *
+ * @return A reference to the HVX callbacks chain.
+ *
+ * @note It is possible to register callbacks using onHVX().add(callback).
+ *
+ * @note It is possible to unregister callbacks using onHVX().detach(callback).
+ */
+ HVXCallbackChain_t& onHVX() {
+ return onHVXCallbackChain;
+ }
+
+public:
+ /**
+ * Notify all registered onShutdown callbacks that the GattClient is
+ * about to be shutdown and clear all GattClient 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 GattClient members. This shall be achieved
+ * by a call to GattClient::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();
+
+ onDataReadCallbackChain.clear();
+ onDataWriteCallbackChain.clear();
+ onHVXCallbackChain.clear();
+
+ return BLE_ERROR_NONE;
+ }
+
+protected:
+ GattClient() {
+ /* Empty */
+ }
+
+ /* Entry points for the underlying stack to report events back to the user. */
+public:
+ /**
+ * 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 processReadResponse(const GattReadCallbackParams *params) {
+ onDataReadCallbackChain(params);
+ }
+
+ /**
+ * 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 processWriteResponse(const GattWriteCallbackParams *params) {
+ onDataWriteCallbackChain(params);
+ }
+
+ /**
+ * Helper function that notifies all registered handlers of an occurrence
+ * of an update event. This function is meant to be called from the
+ * BLE stack specific implementation when an update event occurs.
+ *
+ * @param[in] params
+ * The update event parameters passed to the registered
+ * handlers.
+ */
+ void processHVXEvent(const GattHVXCallbackParams *params) {
+ if (onHVXCallbackChain) {
+ onHVXCallbackChain(params);
+ }
+ }
+
+protected:
+ /**
+ * Callchain containing all registered callback handlers for data read
+ * events.
+ */
+ ReadCallbackChain_t onDataReadCallbackChain;
+ /**
+ * Callchain containing all registered callback handlers for data write
+ * events.
+ */
+ WriteCallbackChain_t onDataWriteCallbackChain;
+ /**
+ * Callchain containing all registered callback handlers for update
+ * events.
+ */
+ HVXCallbackChain_t onHVXCallbackChain;
+ /**
+ * Callchain containing all registered callback handlers for shutdown
+ * events.
+ */
+ GattClientShutdownCallbackChain_t shutdownCallChain;
+
+private:
+ /* Disallow copy and assignment. */
+ GattClient(const GattClient &);
+ GattClient& operator=(const GattClient &);
+};
+
+#endif /* ifndef __GATT_CLIENT_H__ */