erkin yucel / mbed-os

mbed os with nrf51 internal bandgap enabled to read battery level

Dependents:   BLE_file_test BLE_Blink ExternalEncoder

features/FEATURE_BLE/ble/FunctionPointerWithContext.h@0:f269e3021894, 2016-10-23 (annotated)

Committer:
elessair
Date:
Sun Oct 23 15:10:02 2016 +0000
Revision:
0:f269e3021894
Initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
elessair 0:f269e3021894 1 /* mbed Microcontroller Library
elessair 0:f269e3021894 2 * Copyright (c) 2006-2013 ARM Limited
elessair 0:f269e3021894 3 *
elessair 0:f269e3021894 4 * Licensed under the Apache License, Version 2.0 (the "License");
elessair 0:f269e3021894 5 * you may not use this file except in compliance with the License.
elessair 0:f269e3021894 6 * You may obtain a copy of the License at
elessair 0:f269e3021894 7 *
elessair 0:f269e3021894 8 * http://www.apache.org/licenses/LICENSE-2.0
elessair 0:f269e3021894 9 *
elessair 0:f269e3021894 10 * Unless required by applicable law or agreed to in writing, software
elessair 0:f269e3021894 11 * distributed under the License is distributed on an "AS IS" BASIS,
elessair 0:f269e3021894 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
elessair 0:f269e3021894 13 * See the License for the specific language governing permissions and
elessair 0:f269e3021894 14 * limitations under the License.
elessair 0:f269e3021894 15 */
elessair 0:f269e3021894 16
elessair 0:f269e3021894 17 #ifndef MBED_FUNCTIONPOINTER_WITH_CONTEXT_H
elessair 0:f269e3021894 18 #define MBED_FUNCTIONPOINTER_WITH_CONTEXT_H
elessair 0:f269e3021894 19
elessair 0:f269e3021894 20 #include <string.h>
elessair 0:f269e3021894 21 #include "SafeBool.h"
elessair 0:f269e3021894 22
elessair 0:f269e3021894 23 /** A class for storing and calling a pointer to a static or member void function
elessair 0:f269e3021894 24 * that takes a context.
elessair 0:f269e3021894 25 */
elessair 0:f269e3021894 26 template <typename ContextType>
elessair 0:f269e3021894 27 class FunctionPointerWithContext : public SafeBool<FunctionPointerWithContext<ContextType> > {
elessair 0:f269e3021894 28 public:
elessair 0:f269e3021894 29 typedef FunctionPointerWithContext<ContextType> *pFunctionPointerWithContext_t;
elessair 0:f269e3021894 30 typedef const FunctionPointerWithContext<ContextType> *cpFunctionPointerWithContext_t;
elessair 0:f269e3021894 31 typedef void (*pvoidfcontext_t)(ContextType context);
elessair 0:f269e3021894 32
elessair 0:f269e3021894 33 /** Create a FunctionPointerWithContext, attaching a static function.
elessair 0:f269e3021894 34 *
elessair 0:f269e3021894 35 * @param function The void static function to attach (default is none).
elessair 0:f269e3021894 36 */
elessair 0:f269e3021894 37 FunctionPointerWithContext(void (*function)(ContextType context) = NULL) :
elessair 0:f269e3021894 38 _memberFunctionAndPointer(), _caller(NULL), _next(NULL) {
elessair 0:f269e3021894 39 attach(function);
elessair 0:f269e3021894 40 }
elessair 0:f269e3021894 41
elessair 0:f269e3021894 42 /** Create a FunctionPointerWithContext, attaching a member function.
elessair 0:f269e3021894 43 *
elessair 0:f269e3021894 44 * @param object The object pointer to invoke the member function on (the "this" pointer).
elessair 0:f269e3021894 45 * @param function The address of the void member function to attach.
elessair 0:f269e3021894 46 */
elessair 0:f269e3021894 47 template<typename T>
elessair 0:f269e3021894 48 FunctionPointerWithContext(T *object, void (T::*member)(ContextType context)) :
elessair 0:f269e3021894 49 _memberFunctionAndPointer(), _caller(NULL), _next(NULL) {
elessair 0:f269e3021894 50 attach(object, member);
elessair 0:f269e3021894 51 }
elessair 0:f269e3021894 52
elessair 0:f269e3021894 53 FunctionPointerWithContext(const FunctionPointerWithContext& that) :
elessair 0:f269e3021894 54 _memberFunctionAndPointer(that._memberFunctionAndPointer), _caller(that._caller), _next(NULL) {
elessair 0:f269e3021894 55 }
elessair 0:f269e3021894 56
elessair 0:f269e3021894 57 FunctionPointerWithContext& operator=(const FunctionPointerWithContext& that) {
elessair 0:f269e3021894 58 _memberFunctionAndPointer = that._memberFunctionAndPointer;
elessair 0:f269e3021894 59 _caller = that._caller;
elessair 0:f269e3021894 60 _next = NULL;
elessair 0:f269e3021894 61 return *this;
elessair 0:f269e3021894 62 }
elessair 0:f269e3021894 63
elessair 0:f269e3021894 64 /** Attach a static function.
elessair 0:f269e3021894 65 *
elessair 0:f269e3021894 66 * @param function The void static function to attach (default is none).
elessair 0:f269e3021894 67 */
elessair 0:f269e3021894 68 void attach(void (*function)(ContextType context) = NULL) {
elessair 0:f269e3021894 69 _function = function;
elessair 0:f269e3021894 70 _caller = functioncaller;
elessair 0:f269e3021894 71 }
elessair 0:f269e3021894 72
elessair 0:f269e3021894 73 /** Attach a member function.
elessair 0:f269e3021894 74 *
elessair 0:f269e3021894 75 * @param object The object pointer to invoke the member function on (the "this" pointer).
elessair 0:f269e3021894 76 * @param function The address of the void member function to attach.
elessair 0:f269e3021894 77 */
elessair 0:f269e3021894 78 template<typename T>
elessair 0:f269e3021894 79 void attach(T *object, void (T::*member)(ContextType context)) {
elessair 0:f269e3021894 80 _memberFunctionAndPointer._object = static_cast<void *>(object);
elessair 0:f269e3021894 81 memcpy(_memberFunctionAndPointer._memberFunction, (char*) &member, sizeof(member));
elessair 0:f269e3021894 82 _caller = &FunctionPointerWithContext::membercaller<T>;
elessair 0:f269e3021894 83 }
elessair 0:f269e3021894 84
elessair 0:f269e3021894 85 /** Call the attached static or member function; if there are chained
elessair 0:f269e3021894 86 * FunctionPointers their callbacks are invoked as well.
elessair 0:f269e3021894 87 * @Note: All chained callbacks stack up, so hopefully there won't be too
elessair 0:f269e3021894 88 * many FunctionPointers in a chain. */
elessair 0:f269e3021894 89 void call(ContextType context) const {
elessair 0:f269e3021894 90 _caller(this, context);
elessair 0:f269e3021894 91 }
elessair 0:f269e3021894 92
elessair 0:f269e3021894 93 /**
elessair 0:f269e3021894 94 * @brief Same as above
elessair 0:f269e3021894 95 */
elessair 0:f269e3021894 96 void operator()(ContextType context) const {
elessair 0:f269e3021894 97 call(context);
elessair 0:f269e3021894 98 }
elessair 0:f269e3021894 99
elessair 0:f269e3021894 100 /** Same as above, workaround for mbed os FunctionPointer implementation. */
elessair 0:f269e3021894 101 void call(ContextType context) {
elessair 0:f269e3021894 102 ((const FunctionPointerWithContext*) this)->call(context);
elessair 0:f269e3021894 103 }
elessair 0:f269e3021894 104
elessair 0:f269e3021894 105 typedef void (FunctionPointerWithContext::*bool_type)() const;
elessair 0:f269e3021894 106
elessair 0:f269e3021894 107 /**
elessair 0:f269e3021894 108 * implementation of safe bool operator
elessair 0:f269e3021894 109 */
elessair 0:f269e3021894 110 bool toBool() const {
elessair 0:f269e3021894 111 return (_function || _memberFunctionAndPointer._object);
elessair 0:f269e3021894 112 }
elessair 0:f269e3021894 113
elessair 0:f269e3021894 114 /**
elessair 0:f269e3021894 115 * Set up an external FunctionPointer as a next in the chain of related
elessair 0:f269e3021894 116 * callbacks. Invoking call() on the head FunctionPointer will invoke all
elessair 0:f269e3021894 117 * chained callbacks.
elessair 0:f269e3021894 118 *
elessair 0:f269e3021894 119 * Refer to 'CallChain' as an alternative.
elessair 0:f269e3021894 120 */
elessair 0:f269e3021894 121 void chainAsNext(pFunctionPointerWithContext_t next) {
elessair 0:f269e3021894 122 _next = next;
elessair 0:f269e3021894 123 }
elessair 0:f269e3021894 124
elessair 0:f269e3021894 125 pFunctionPointerWithContext_t getNext(void) const {
elessair 0:f269e3021894 126 return _next;
elessair 0:f269e3021894 127 }
elessair 0:f269e3021894 128
elessair 0:f269e3021894 129 pvoidfcontext_t get_function() const {
elessair 0:f269e3021894 130 return (pvoidfcontext_t)_function;
elessair 0:f269e3021894 131 }
elessair 0:f269e3021894 132
elessair 0:f269e3021894 133 friend bool operator==(const FunctionPointerWithContext& lhs, const FunctionPointerWithContext& rhs) {
elessair 0:f269e3021894 134 return rhs._caller == lhs._caller &&
elessair 0:f269e3021894 135 memcmp(
elessair 0:f269e3021894 136 &rhs._memberFunctionAndPointer,
elessair 0:f269e3021894 137 &lhs._memberFunctionAndPointer,
elessair 0:f269e3021894 138 sizeof(rhs._memberFunctionAndPointer)
elessair 0:f269e3021894 139 ) == 0;
elessair 0:f269e3021894 140 }
elessair 0:f269e3021894 141
elessair 0:f269e3021894 142 private:
elessair 0:f269e3021894 143 template<typename T>
elessair 0:f269e3021894 144 static void membercaller(cpFunctionPointerWithContext_t self, ContextType context) {
elessair 0:f269e3021894 145 if (self->_memberFunctionAndPointer._object) {
elessair 0:f269e3021894 146 T *o = static_cast<T *>(self->_memberFunctionAndPointer._object);
elessair 0:f269e3021894 147 void (T::*m)(ContextType);
elessair 0:f269e3021894 148 memcpy((char*) &m, self->_memberFunctionAndPointer._memberFunction, sizeof(m));
elessair 0:f269e3021894 149 (o->*m)(context);
elessair 0:f269e3021894 150 }
elessair 0:f269e3021894 151 }
elessair 0:f269e3021894 152
elessair 0:f269e3021894 153 static void functioncaller(cpFunctionPointerWithContext_t self, ContextType context) {
elessair 0:f269e3021894 154 if (self->_function) {
elessair 0:f269e3021894 155 self->_function(context);
elessair 0:f269e3021894 156 }
elessair 0:f269e3021894 157 }
elessair 0:f269e3021894 158
elessair 0:f269e3021894 159 struct MemberFunctionAndPtr {
elessair 0:f269e3021894 160 /*
elessair 0:f269e3021894 161 * Forward declaration of a class and a member function to this class.
elessair 0:f269e3021894 162 * Because the compiler doesn't know anything about the forwarded member
elessair 0:f269e3021894 163 * function, it will always use the biggest size and the biggest alignment
elessair 0:f269e3021894 164 * that a member function can take for objects of type UndefinedMemberFunction.
elessair 0:f269e3021894 165 */
elessair 0:f269e3021894 166 class UndefinedClass;
elessair 0:f269e3021894 167 typedef void (UndefinedClass::*UndefinedMemberFunction)(ContextType);
elessair 0:f269e3021894 168
elessair 0:f269e3021894 169 void* _object;
elessair 0:f269e3021894 170 union {
elessair 0:f269e3021894 171 char _memberFunction[sizeof(UndefinedMemberFunction)];
elessair 0:f269e3021894 172 UndefinedMemberFunction _alignment;
elessair 0:f269e3021894 173 };
elessair 0:f269e3021894 174 };
elessair 0:f269e3021894 175
elessair 0:f269e3021894 176 union {
elessair 0:f269e3021894 177 pvoidfcontext_t _function; /**< Static function pointer - NULL if none attached */
elessair 0:f269e3021894 178 /**
elessair 0:f269e3021894 179 * object this pointer and pointer to member -
elessair 0:f269e3021894 180 * _memberFunctionAndPointer._object will be NULL if none attached
elessair 0:f269e3021894 181 */
elessair 0:f269e3021894 182 mutable MemberFunctionAndPtr _memberFunctionAndPointer;
elessair 0:f269e3021894 183 };
elessair 0:f269e3021894 184
elessair 0:f269e3021894 185 void (*_caller)(const FunctionPointerWithContext*, ContextType);
elessair 0:f269e3021894 186
elessair 0:f269e3021894 187 pFunctionPointerWithContext_t _next; /**< Optional link to make a chain out of functionPointers. This
elessair 0:f269e3021894 188 * allows chaining function pointers without requiring
elessair 0:f269e3021894 189 * external memory to manage the chain. Refer to
elessair 0:f269e3021894 190 * 'CallChain' as an alternative. */
elessair 0:f269e3021894 191 };
elessair 0:f269e3021894 192
elessair 0:f269e3021894 193 /**
elessair 0:f269e3021894 194 * @brief Create a new FunctionPointerWithContext which bind an instance and a
elessair 0:f269e3021894 195 * a member function together.
elessair 0:f269e3021894 196 * @details This little helper is a just here to eliminate the need to write the
elessair 0:f269e3021894 197 * FunctionPointerWithContext type each time you want to create one by kicking
elessair 0:f269e3021894 198 * automatic type deduction of function templates. With this function, it is easy
elessair 0:f269e3021894 199 * to write only one entry point for functions which expect a FunctionPointer
elessair 0:f269e3021894 200 * in parameters.
elessair 0:f269e3021894 201 *
elessair 0:f269e3021894 202 * @param object to bound with member function
elessair 0:f269e3021894 203 * @param member The member function called
elessair 0:f269e3021894 204 * @return a new FunctionPointerWithContext
elessair 0:f269e3021894 205 */
elessair 0:f269e3021894 206 template<typename T, typename ContextType>
elessair 0:f269e3021894 207 FunctionPointerWithContext<ContextType> makeFunctionPointer(T *object, void (T::*member)(ContextType context))
elessair 0:f269e3021894 208 {
elessair 0:f269e3021894 209 return FunctionPointerWithContext<ContextType>(object, member);
elessair 0:f269e3021894 210 }
elessair 0:f269e3021894 211
elessair 0:f269e3021894 212 #endif // ifndef MBED_FUNCTIONPOINTER_WITH_CONTEXT_H