tool/mbed/mbed-sdk/libraries/mbed/api/FunctionPointer.h

   1 /* mbed Microcontroller Library
   2  * Copyright (c) 2006-2013 ARM Limited
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 #ifndef MBED_FUNCTIONPOINTER_H
  17 #define MBED_FUNCTIONPOINTER_H
  18
  19 #include <string.h>
  20
  21 namespace mbed {
  22
  23 typedef void (*pvoidf_t)(void);
  24
  25 /** A class for storing and calling a pointer to a static or member void function
  26  */
  27 class FunctionPointer {
  28 public:
  29
  30     /** Create a FunctionPointer, attaching a static function
  31      *
  32      *  @param function The void static function to attach (default is none)
  33      */
  34     FunctionPointer(void (*function)(void) = 0);
  35
  36     /** Create a FunctionPointer, attaching a member function
  37      *
  38      *  @param object The object pointer to invoke the member function on (i.e. the this pointer)
  39      *  @param function The address of the void member function to attach
  40      */
  41     template<typename T>
  42     FunctionPointer(T *object, void (T::*member)(void)) {
  43         attach(object, member);
  44     }
  45
  46     /** Attach a static function
  47      *
  48      *  @param function The void static function to attach (default is none)
  49      */
  50     void attach(void (*function)(void) = 0);
  51
  52     /** Attach a member function
  53      *
  54      *  @param object The object pointer to invoke the member function on (i.e. the this pointer)
  55      *  @param function The address of the void member function to attach
  56      */
  57     template<typename T>
  58     void attach(T *object, void (T::*member)(void)) {
  59         _object = static_cast<void*>(object);
  60         memcpy(_member, (char*)&member, sizeof(member));
  61         _membercaller = &FunctionPointer::membercaller<T>;
  62         _function = 0;
  63     }
  64
  65     /** Call the attached static or member function
  66      */
  67     void call();
  68
  69     pvoidf_t get_function() const {
  70         return (pvoidf_t)_function;
  71     }
  72
  73 #ifdef MBED_OPERATORS
  74     void operator ()(void);
  75 #endif
  76
  77 private:
  78     template<typename T>
  79     static void membercaller(void *object, char *member) {
  80         T* o = static_cast<T*>(object);
  81         void (T::*m)(void);
  82         memcpy((char*)&m, member, sizeof(m));
  83         (o->*m)();
  84     }
  85
  86     void (*_function)(void);             // static function pointer - 0 if none attached
  87     void *_object;                       // object this pointer - 0 if none attached
  88     char _member[16];                    // raw member function pointer storage - converted back by registered _membercaller
  89     void (*_membercaller)(void*, char*); // registered membercaller function to convert back and call _member on _object
  90 };
  91
  92 } // namespace mbed
  93
  94 #endif