Ram Gandikota / Mbed OS ABCD

A metronome using the FRDM K64F board

mbed-client/test/mbedclient/utest/common/FunctionPointerBase.h@0:a7a43371b306, 2017-05-14 (annotated)

Committer:
ram54288
Date:
Sun May 14 18:40:18 2017 +0000
Revision:
0:a7a43371b306
Initial commit

Who changed what in which revision?

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ram54288 0:a7a43371b306 1 /* mbed Microcontroller Library
ram54288 0:a7a43371b306 2 * Copyright (c) 2015 ARM Limited
ram54288 0:a7a43371b306 3 *
ram54288 0:a7a43371b306 4 * Licensed under the Apache License, Version 2.0 (the "License");
ram54288 0:a7a43371b306 5 * you may not use this file except in compliance with the License.
ram54288 0:a7a43371b306 6 * You may obtain a copy of the License at
ram54288 0:a7a43371b306 7 *
ram54288 0:a7a43371b306 8 * http://www.apache.org/licenses/LICENSE-2.0
ram54288 0:a7a43371b306 9 *
ram54288 0:a7a43371b306 10 * Unless required by applicable law or agreed to in writing, software
ram54288 0:a7a43371b306 11 * distributed under the License is distributed on an "AS IS" BASIS,
ram54288 0:a7a43371b306 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
ram54288 0:a7a43371b306 13 * See the License for the specific language governing permissions and
ram54288 0:a7a43371b306 14 * limitations under the License.
ram54288 0:a7a43371b306 15 */
ram54288 0:a7a43371b306 16 #ifndef MBED_FUNCTIONPOINTERBASE_H
ram54288 0:a7a43371b306 17 #define MBED_FUNCTIONPOINTERBASE_H
ram54288 0:a7a43371b306 18
ram54288 0:a7a43371b306 19 #include <string.h>
ram54288 0:a7a43371b306 20 #include <stdint.h>
ram54288 0:a7a43371b306 21 #include <stddef.h>
ram54288 0:a7a43371b306 22 #include <stdarg.h>
ram54288 0:a7a43371b306 23 namespace mbed {
ram54288 0:a7a43371b306 24
ram54288 0:a7a43371b306 25 template<typename R>
ram54288 0:a7a43371b306 26 class FunctionPointerBase {
ram54288 0:a7a43371b306 27 public:
ram54288 0:a7a43371b306 28 operator bool(void) const {
ram54288 0:a7a43371b306 29 return (_membercaller != NULL) && (_object != NULL);
ram54288 0:a7a43371b306 30 }
ram54288 0:a7a43371b306 31
ram54288 0:a7a43371b306 32 /**
ram54288 0:a7a43371b306 33 * Clears the current function pointer assignment
ram54288 0:a7a43371b306 34 * After clear(), this instance will point to nothing (NULL)
ram54288 0:a7a43371b306 35 */
ram54288 0:a7a43371b306 36 virtual void clear() {
ram54288 0:a7a43371b306 37 _membercaller = NULL;
ram54288 0:a7a43371b306 38 _object = NULL;
ram54288 0:a7a43371b306 39 }
ram54288 0:a7a43371b306 40
ram54288 0:a7a43371b306 41 protected:
ram54288 0:a7a43371b306 42 struct ArgOps {
ram54288 0:a7a43371b306 43 void (*constructor)(void *, va_list);
ram54288 0:a7a43371b306 44 void (*copy_args)(void *, void *);
ram54288 0:a7a43371b306 45 void (*destructor)(void *);
ram54288 0:a7a43371b306 46 };
ram54288 0:a7a43371b306 47 void * _object; // object Pointer/function pointer
ram54288 0:a7a43371b306 48 R (*_membercaller)(void *, uintptr_t *, void *);
ram54288 0:a7a43371b306 49 // aligned raw member function pointer storage - converted back by registered _membercaller
ram54288 0:a7a43371b306 50 uintptr_t _member[4];
ram54288 0:a7a43371b306 51 static const struct ArgOps _nullops;
ram54288 0:a7a43371b306 52
ram54288 0:a7a43371b306 53 protected:
ram54288 0:a7a43371b306 54 FunctionPointerBase():_object(NULL), _membercaller(NULL) {}
ram54288 0:a7a43371b306 55 FunctionPointerBase(const FunctionPointerBase<R> & fp) {
ram54288 0:a7a43371b306 56 copy(&fp);
ram54288 0:a7a43371b306 57 }
ram54288 0:a7a43371b306 58 virtual ~FunctionPointerBase() {
ram54288 0:a7a43371b306 59 }
ram54288 0:a7a43371b306 60
ram54288 0:a7a43371b306 61 /**
ram54288 0:a7a43371b306 62 * Calls the member pointed to by object::member or (function)object
ram54288 0:a7a43371b306 63 * @param arg
ram54288 0:a7a43371b306 64 * @return
ram54288 0:a7a43371b306 65 */
ram54288 0:a7a43371b306 66 inline R call(void* arg) {
ram54288 0:a7a43371b306 67 return _membercaller(_object, _member, arg);
ram54288 0:a7a43371b306 68 }
ram54288 0:a7a43371b306 69
ram54288 0:a7a43371b306 70 void copy(const FunctionPointerBase<R> * fp) {
ram54288 0:a7a43371b306 71 _object = fp->_object;
ram54288 0:a7a43371b306 72 memcpy (_member, fp->_member, sizeof(_member));
ram54288 0:a7a43371b306 73 _membercaller = fp->_membercaller;
ram54288 0:a7a43371b306 74 }
ram54288 0:a7a43371b306 75 private:
ram54288 0:a7a43371b306 76 static void _null_constructor(void * dest, va_list args) {(void) dest;(void) args;}
ram54288 0:a7a43371b306 77 static void _null_copy_args(void *dest , void* src) {(void) dest; (void) src;}
ram54288 0:a7a43371b306 78 static void _null_destructor(void *args) {(void) args;}
ram54288 0:a7a43371b306 79
ram54288 0:a7a43371b306 80 };
ram54288 0:a7a43371b306 81 template<typename R>
ram54288 0:a7a43371b306 82 const struct FunctionPointerBase<R>::ArgOps FunctionPointerBase<R>::_nullops = {
ram54288 0:a7a43371b306 83 FunctionPointerBase<R>::_null_constructor,
ram54288 0:a7a43371b306 84 FunctionPointerBase<R>::_null_copy_args,
ram54288 0:a7a43371b306 85 FunctionPointerBase<R>::_null_destructor
ram54288 0:a7a43371b306 86 };
ram54288 0:a7a43371b306 87
ram54288 0:a7a43371b306 88 }
ram54288 0:a7a43371b306 89 #endif