CallChain.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 #ifndef MBED_CALLCHAIN_H
00017 #define MBED_CALLCHAIN_H
00018 
00019 #include "Callback.h"
00020 #include <string.h>
00021 
00022 namespace mbed {
00023 
00024 /** Group one or more functions in an instance of a CallChain, then call them in
00025  * sequence using CallChain::call(). Used mostly by the interrupt chaining code,
00026  * but can be used for other purposes.
00027  *
00028  * @Note Synchronization level: Not protected
00029  *
00030  * Example:
00031  * @code
00032  * #include "mbed.h"
00033  *
00034  * CallChain chain;
00035  *
00036  * void first(void) {
00037  *     printf("'first' function.\n");
00038  * }
00039  *
00040  * void second(void) {
00041  *     printf("'second' function.\n");
00042  * }
00043  *
00044  * class Test {
00045  * public:
00046  *     void f(void) {
00047  *         printf("A::f (class member).\n");
00048  *     }
00049  * };
00050  *
00051  * int main() {
00052  *     Test test;
00053  *
00054  *     chain.add(second);
00055  *     chain.add_front(first);
00056  *     chain.add(&test, &Test::f);
00057  *     chain.call();
00058  * }
00059  * @endcode
00060  */
00061 
00062 typedef Callback<void()> *pFunctionPointer_t;
00063 class CallChainLink;
00064 
00065 class CallChain {
00066 public:
00067     /** Create an empty chain
00068      *
00069      *  @param size (optional) Initial size of the chain
00070      */
00071     CallChain(int size = 4);
00072     virtual ~CallChain();
00073 
00074     /** Add a function at the end of the chain
00075      *
00076      *  @param func A pointer to a void function
00077      *
00078      *  @returns
00079      *  The function object created for 'func'
00080      */
00081     pFunctionPointer_t add(Callback<void()> func);
00082 
00083     /** Add a function at the end of the chain
00084      *
00085      *  @param obj pointer to the object to call the member function on
00086      *  @param method pointer to the member function to be called
00087      *
00088      *  @returns
00089      *  The function object created for 'obj' and 'method'
00090      */
00091     template<typename T, typename M>
00092     pFunctionPointer_t add(T *obj, M method) {
00093         return add(Callback<void()>(obj, method));
00094     }
00095 
00096     /** Add a function at the beginning of the chain
00097      *
00098      *  @param func A pointer to a void function
00099      *
00100      *  @returns
00101      *  The function object created for 'func'
00102      */
00103     pFunctionPointer_t add_front(Callback<void()> func);
00104 
00105     /** Add a function at the beginning of the chain
00106      *
00107      *  @param tptr pointer to the object to call the member function on
00108      *  @param mptr pointer to the member function to be called
00109      *
00110      *  @returns
00111      *  The function object created for 'tptr' and 'mptr'
00112      */
00113     template<typename T, typename M>
00114     pFunctionPointer_t add_front(T *obj, M method) {
00115         return add_front(Callback<void()>(obj, method));
00116     }
00117 
00118     /** Get the number of functions in the chain
00119      */
00120     int size() const;
00121 
00122     /** Get a function object from the chain
00123      *
00124      *  @param i function object index
00125      *
00126      *  @returns
00127      *  The function object at position 'i' in the chain
00128      */
00129     pFunctionPointer_t get(int i) const;
00130 
00131     /** Look for a function object in the call chain
00132      *
00133      *  @param f the function object to search
00134      *
00135      *  @returns
00136      *  The index of the function object if found, -1 otherwise.
00137      */
00138     int find(pFunctionPointer_t f) const;
00139 
00140     /** Clear the call chain (remove all functions in the chain).
00141      */
00142     void clear();
00143 
00144     /** Remove a function object from the chain
00145      *
00146      *  @arg f the function object to remove
00147      *
00148      *  @returns
00149      *  true if the function object was found and removed, false otherwise.
00150      */
00151     bool remove(pFunctionPointer_t f);
00152 
00153     /** Call all the functions in the chain in sequence
00154      */
00155     void call();
00156 
00157     void operator ()(void) {
00158         call();
00159     }
00160     pFunctionPointer_t operator [](int i) const {
00161         return get(i);
00162     }
00163 
00164     /* disallow copy constructor and assignment operators */
00165 private:
00166     CallChain(const CallChain&);
00167     CallChain & operator = (const CallChain&);
00168     CallChainLink *_chain;
00169 };
00170 
00171 } // namespace mbed
00172 
00173 #endif