Wang Xinglu / BLE_API

High level Bluetooth Low Energy API and radio abstraction layer

Dependencies:   nRF51822

Dependents:   LinkNode_LIS3DH

Fork of BLE_API by Bluetooth Low Energy

public/FunctionPointerWithContext.h@118:620d28e7a1ba, 2014-09-22 (annotated)

Committer:
Rohit Grover
Date:
Mon Sep 22 10:59:09 2014 +0100
Revision:
118:620d28e7a1ba
Child:
126:fdebe4d5d62f
Release 0.2.0

=============



Highlights:

  Introducing standard services to simplify applications.

  Add support for over-the-air firmware updates.



Features

~~~~~~~~



- This release introduces 'templates' for common services such as heart-rate,

  battery-level, device-info, UART, device-firmware-update etc. These services

  take the shape of class declarations within header files aggregated under a

  new folder called 'services/'. These service-classes provide a high-level

  API hopefully easing the burden of developing BLE applications. The

  underlying APIs to work with characteristics and services are still

  available to allow greater control if needed. We expect to grow the

  supported services to include all SIG defined BLE profiles.



- WriteCallbackParams now includes the characteristic's value-attribute

  handle; this changes the signature of onDataWritten().



- BLEDevice::onDataWritten() now allows chaining of callbacks--this means that

  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. It is

  also possible to chain callbacks to functions within objects.



- Added the following expectation for GattCharacteristic: If valuePtr ==

  NULL, initialLength == 0, and properties == READ for the value attribute of

  a characteristic, then that particular characteristic may be considered

  optional and dropped while instantiating the service with the underlying BLE

  stack.



- Introducing the typedef GattAttribute::Handle_t to capture Attribute handles.



Bugfixes

~~~~~~~~



None.



Compatibility

~~~~~~~~~~~~~



The signature of onDataWritten() has seen a change; so application programs

using this new version of the BLE API will need minor modifications. Please

refer to sample programs under BLE team page.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Rohit Grover 118:620d28e7a1ba 1 /* mbed Microcontroller Library
Rohit Grover 118:620d28e7a1ba 2 * Copyright (c) 2006-2013 ARM Limited
Rohit Grover 118:620d28e7a1ba 3 *
Rohit Grover 118:620d28e7a1ba 4 * Licensed under the Apache License, Version 2.0 (the "License");
Rohit Grover 118:620d28e7a1ba 5 * you may not use this file except in compliance with the License.
Rohit Grover 118:620d28e7a1ba 6 * You may obtain a copy of the License at
Rohit Grover 118:620d28e7a1ba 7 *
Rohit Grover 118:620d28e7a1ba 8 * http://www.apache.org/licenses/LICENSE-2.0
Rohit Grover 118:620d28e7a1ba 9 *
Rohit Grover 118:620d28e7a1ba 10 * Unless required by applicable law or agreed to in writing, software
Rohit Grover 118:620d28e7a1ba 11 * distributed under the License is distributed on an "AS IS" BASIS,
Rohit Grover 118:620d28e7a1ba 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
Rohit Grover 118:620d28e7a1ba 13 * See the License for the specific language governing permissions and
Rohit Grover 118:620d28e7a1ba 14 * limitations under the License.
Rohit Grover 118:620d28e7a1ba 15 */
Rohit Grover 118:620d28e7a1ba 16
Rohit Grover 118:620d28e7a1ba 17 #ifndef MBED_FUNCTIONPOINTER_WITH_CONTEXT_H
Rohit Grover 118:620d28e7a1ba 18 #define MBED_FUNCTIONPOINTER_WITH_CONTEXT_H
Rohit Grover 118:620d28e7a1ba 19
Rohit Grover 118:620d28e7a1ba 20 #include <string.h>
Rohit Grover 118:620d28e7a1ba 21
Rohit Grover 118:620d28e7a1ba 22 namespace mbed {
Rohit Grover 118:620d28e7a1ba 23
Rohit Grover 118:620d28e7a1ba 24 /** A class for storing and calling a pointer to a static or member void function
Rohit Grover 118:620d28e7a1ba 25 * which takes a context.
Rohit Grover 118:620d28e7a1ba 26 */
Rohit Grover 118:620d28e7a1ba 27 template <typename ContextType>
Rohit Grover 118:620d28e7a1ba 28 class FunctionPointerWithContext {
Rohit Grover 118:620d28e7a1ba 29 public:
Rohit Grover 118:620d28e7a1ba 30 typedef FunctionPointerWithContext<ContextType> *pFunctionPointerWithContext_t;
Rohit Grover 118:620d28e7a1ba 31 typedef void (*pvoidfcontext_t)(ContextType context);
Rohit Grover 118:620d28e7a1ba 32
Rohit Grover 118:620d28e7a1ba 33 /** Create a FunctionPointerWithContext, attaching a static function
Rohit Grover 118:620d28e7a1ba 34 *
Rohit Grover 118:620d28e7a1ba 35 * @param function The void static function to attach (default is none)
Rohit Grover 118:620d28e7a1ba 36 */
Rohit Grover 118:620d28e7a1ba 37 FunctionPointerWithContext(void (*function)(ContextType context) = NULL) :
Rohit Grover 118:620d28e7a1ba 38 _function(NULL), _object(NULL), _member(), _membercaller(NULL), _next(NULL) {
Rohit Grover 118:620d28e7a1ba 39 attach(function);
Rohit Grover 118:620d28e7a1ba 40 }
Rohit Grover 118:620d28e7a1ba 41
Rohit Grover 118:620d28e7a1ba 42 /** Create a FunctionPointerWithContext, attaching a member function
Rohit Grover 118:620d28e7a1ba 43 *
Rohit Grover 118:620d28e7a1ba 44 * @param object The object pointer to invoke the member function on (i.e. the this pointer)
Rohit Grover 118:620d28e7a1ba 45 * @param function The address of the void member function to attach
Rohit Grover 118:620d28e7a1ba 46 */
Rohit Grover 118:620d28e7a1ba 47 template<typename T>
Rohit Grover 118:620d28e7a1ba 48 FunctionPointerWithContext(T *object, void (T::*member)(ContextType context)) :
Rohit Grover 118:620d28e7a1ba 49 _function(NULL), _object(NULL), _member(), _membercaller(NULL), _next(NULL) {
Rohit Grover 118:620d28e7a1ba 50 attach(object, member);
Rohit Grover 118:620d28e7a1ba 51 }
Rohit Grover 118:620d28e7a1ba 52
Rohit Grover 118:620d28e7a1ba 53 /** Attach a static function
Rohit Grover 118:620d28e7a1ba 54 *
Rohit Grover 118:620d28e7a1ba 55 * @param function The void static function to attach (default is none)
Rohit Grover 118:620d28e7a1ba 56 */
Rohit Grover 118:620d28e7a1ba 57 void attach(void (*function)(ContextType context) = NULL) {
Rohit Grover 118:620d28e7a1ba 58 _function = function;
Rohit Grover 118:620d28e7a1ba 59 }
Rohit Grover 118:620d28e7a1ba 60
Rohit Grover 118:620d28e7a1ba 61 /** Attach a member function
Rohit Grover 118:620d28e7a1ba 62 *
Rohit Grover 118:620d28e7a1ba 63 * @param object The object pointer to invoke the member function on (i.e. the this pointer)
Rohit Grover 118:620d28e7a1ba 64 * @param function The address of the void member function to attach
Rohit Grover 118:620d28e7a1ba 65 */
Rohit Grover 118:620d28e7a1ba 66 template<typename T>
Rohit Grover 118:620d28e7a1ba 67 void attach(T *object, void (T::*member)(ContextType context)) {
Rohit Grover 118:620d28e7a1ba 68 _object = static_cast<void *>(object);
Rohit Grover 118:620d28e7a1ba 69 memcpy(_member, (char *)&member, sizeof(member));
Rohit Grover 118:620d28e7a1ba 70 _membercaller = &FunctionPointerWithContext::membercaller<T>;
Rohit Grover 118:620d28e7a1ba 71 }
Rohit Grover 118:620d28e7a1ba 72
Rohit Grover 118:620d28e7a1ba 73 /** Call the attached static or member function; and if there are chained
Rohit Grover 118:620d28e7a1ba 74 * FunctionPointers their callbacks are invoked as well.
Rohit Grover 118:620d28e7a1ba 75 * @Note: all chained callbacks stack up; so hopefully there won't be too
Rohit Grover 118:620d28e7a1ba 76 * many FunctionPointers in a chain. */
Rohit Grover 118:620d28e7a1ba 77 void call(ContextType context) {
Rohit Grover 118:620d28e7a1ba 78 if (_function) {
Rohit Grover 118:620d28e7a1ba 79 _function(context);
Rohit Grover 118:620d28e7a1ba 80 } else if (_object && _membercaller) {
Rohit Grover 118:620d28e7a1ba 81 _membercaller(_object, _member, context);
Rohit Grover 118:620d28e7a1ba 82 }
Rohit Grover 118:620d28e7a1ba 83
Rohit Grover 118:620d28e7a1ba 84 /* Propagate the call to next in the chain. */
Rohit Grover 118:620d28e7a1ba 85 if (_next) {
Rohit Grover 118:620d28e7a1ba 86 _next->call(context);
Rohit Grover 118:620d28e7a1ba 87 }
Rohit Grover 118:620d28e7a1ba 88 }
Rohit Grover 118:620d28e7a1ba 89
Rohit Grover 118:620d28e7a1ba 90 /**
Rohit Grover 118:620d28e7a1ba 91 * Setup an external FunctionPointer as a next in the chain of related
Rohit Grover 118:620d28e7a1ba 92 * callbacks. Invoking call() on the head FunctionPointer will invoke all
Rohit Grover 118:620d28e7a1ba 93 * chained callbacks.
Rohit Grover 118:620d28e7a1ba 94 *
Rohit Grover 118:620d28e7a1ba 95 * Refer to 'CallChain' as an alternative.
Rohit Grover 118:620d28e7a1ba 96 */
Rohit Grover 118:620d28e7a1ba 97 void chainAsNext(pFunctionPointerWithContext_t next) {
Rohit Grover 118:620d28e7a1ba 98 _next = next;
Rohit Grover 118:620d28e7a1ba 99 }
Rohit Grover 118:620d28e7a1ba 100
Rohit Grover 118:620d28e7a1ba 101 pFunctionPointerWithContext_t getNext(void) const {
Rohit Grover 118:620d28e7a1ba 102 return _next;
Rohit Grover 118:620d28e7a1ba 103 }
Rohit Grover 118:620d28e7a1ba 104
Rohit Grover 118:620d28e7a1ba 105 pvoidfcontext_t get_function() const {
Rohit Grover 118:620d28e7a1ba 106 return (pvoidfcontext_t)_function;
Rohit Grover 118:620d28e7a1ba 107 }
Rohit Grover 118:620d28e7a1ba 108
Rohit Grover 118:620d28e7a1ba 109 private:
Rohit Grover 118:620d28e7a1ba 110 template<typename T>
Rohit Grover 118:620d28e7a1ba 111 static void membercaller(void *object, char *member, ContextType context) {
Rohit Grover 118:620d28e7a1ba 112 T *o = static_cast<T *>(object);
Rohit Grover 118:620d28e7a1ba 113 void (T::*m)(ContextType);
Rohit Grover 118:620d28e7a1ba 114 memcpy((char *)&m, member, sizeof(m));
Rohit Grover 118:620d28e7a1ba 115 (o->*m)(context);
Rohit Grover 118:620d28e7a1ba 116 }
Rohit Grover 118:620d28e7a1ba 117
Rohit Grover 118:620d28e7a1ba 118 void (*_function)(ContextType context); /**< static function pointer - NULL if none attached */
Rohit Grover 118:620d28e7a1ba 119 void *_object; /**< object this pointer - NULL if none attached */
Rohit Grover 118:620d28e7a1ba 120 char _member[16]; /**< raw member function pointer storage - converted back by
Rohit Grover 118:620d28e7a1ba 121 * registered _membercaller */
Rohit Grover 118:620d28e7a1ba 122 void (*_membercaller)(void *, char *, ContextType); /**< registered membercaller function to convert back and call
Rohit Grover 118:620d28e7a1ba 123 * _member on _object passing the context. */
Rohit Grover 118:620d28e7a1ba 124 pFunctionPointerWithContext_t _next; /**< Optional link to make a chain out of functionPointers; this
Rohit Grover 118:620d28e7a1ba 125 * allows chaining function pointers without requiring
Rohit Grover 118:620d28e7a1ba 126 * external memory to manage the chain. Also refer to
Rohit Grover 118:620d28e7a1ba 127 * 'CallChain' as an alternative. */
Rohit Grover 118:620d28e7a1ba 128 };
Rohit Grover 118:620d28e7a1ba 129 } // namespace mbed
Rohit Grover 118:620d28e7a1ba 130
Rohit Grover 118:620d28e7a1ba 131 #endif // ifndef MBED_FUNCTIONPOINTER_WITH_CONTEXT_H