Aditya Mehrotra / mbed-dev

Biomimetics MBED Library w/ Added Support for CAN3

Dependents:   CAN_TEST SPIne_Plus_DYNO_SENSORS SPIne_Plus_v2 SPIne_Plus_Dyno_v2

platform/SingletonPtr.h@3:993b4d6ff61e, 2021-03-09 (annotated)

Committer:
adimmit
Date:
Tue Mar 09 20:33:24 2021 +0000
Revision:
3:993b4d6ff61e
Parent:
0:083111ae2a11 
added CAN3

Who changed what in which revision?

UserRevisionLine numberNew contents of line
saloutos 0:083111ae2a11 1
saloutos 0:083111ae2a11 2 /** \addtogroup platform */
saloutos 0:083111ae2a11 3 /** @{*/
saloutos 0:083111ae2a11 4 /* mbed Microcontroller Library
saloutos 0:083111ae2a11 5 * Copyright (c) 2006-2013 ARM Limited
saloutos 0:083111ae2a11 6 *
saloutos 0:083111ae2a11 7 * Licensed under the Apache License, Version 2.0 (the "License");
saloutos 0:083111ae2a11 8 * you may not use this file except in compliance with the License.
saloutos 0:083111ae2a11 9 * You may obtain a copy of the License at
saloutos 0:083111ae2a11 10 *
saloutos 0:083111ae2a11 11 * http://www.apache.org/licenses/LICENSE-2.0
saloutos 0:083111ae2a11 12 *
saloutos 0:083111ae2a11 13 * Unless required by applicable law or agreed to in writing, software
saloutos 0:083111ae2a11 14 * distributed under the License is distributed on an "AS IS" BASIS,
saloutos 0:083111ae2a11 15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
saloutos 0:083111ae2a11 16 * See the License for the specific language governing permissions and
saloutos 0:083111ae2a11 17 * limitations under the License.
saloutos 0:083111ae2a11 18 */
saloutos 0:083111ae2a11 19 #ifndef SINGLETONPTR_H
saloutos 0:083111ae2a11 20 #define SINGLETONPTR_H
saloutos 0:083111ae2a11 21
saloutos 0:083111ae2a11 22 #include <stdint.h>
saloutos 0:083111ae2a11 23 #include <new>
saloutos 0:083111ae2a11 24 #include "platform/mbed_assert.h"
saloutos 0:083111ae2a11 25 #ifdef MBED_CONF_RTOS_PRESENT
saloutos 0:083111ae2a11 26 #include "cmsis_os2.h"
saloutos 0:083111ae2a11 27 #endif
saloutos 0:083111ae2a11 28
saloutos 0:083111ae2a11 29 #ifdef MBED_CONF_RTOS_PRESENT
saloutos 0:083111ae2a11 30 extern osMutexId_t singleton_mutex_id;
saloutos 0:083111ae2a11 31 #endif
saloutos 0:083111ae2a11 32
saloutos 0:083111ae2a11 33 /** Lock the singleton mutex
saloutos 0:083111ae2a11 34 *
saloutos 0:083111ae2a11 35 * This function is typically used to provide
saloutos 0:083111ae2a11 36 * exclusive access when initializing a
saloutos 0:083111ae2a11 37 * global object.
saloutos 0:083111ae2a11 38 */
saloutos 0:083111ae2a11 39 inline static void singleton_lock(void)
saloutos 0:083111ae2a11 40 {
saloutos 0:083111ae2a11 41 #ifdef MBED_CONF_RTOS_PRESENT
saloutos 0:083111ae2a11 42 osMutexAcquire(singleton_mutex_id, osWaitForever);
saloutos 0:083111ae2a11 43 #endif
saloutos 0:083111ae2a11 44 }
saloutos 0:083111ae2a11 45
saloutos 0:083111ae2a11 46 /** Unlock the singleton mutex
saloutos 0:083111ae2a11 47 *
saloutos 0:083111ae2a11 48 * This function is typically used to provide
saloutos 0:083111ae2a11 49 * exclusive access when initializing a
saloutos 0:083111ae2a11 50 * global object.
saloutos 0:083111ae2a11 51 */
saloutos 0:083111ae2a11 52 inline static void singleton_unlock(void)
saloutos 0:083111ae2a11 53 {
saloutos 0:083111ae2a11 54 #ifdef MBED_CONF_RTOS_PRESENT
saloutos 0:083111ae2a11 55 osMutexRelease (singleton_mutex_id);
saloutos 0:083111ae2a11 56 #endif
saloutos 0:083111ae2a11 57 }
saloutos 0:083111ae2a11 58 /** @}*/
saloutos 0:083111ae2a11 59
saloutos 0:083111ae2a11 60 /** Utility class for creating an using a singleton
saloutos 0:083111ae2a11 61 *
saloutos 0:083111ae2a11 62 * @note Synchronization level: Thread safe
saloutos 0:083111ae2a11 63 *
saloutos 0:083111ae2a11 64 * @note: This class must only be used in a static context -
saloutos 0:083111ae2a11 65 * this class must never be allocated or created on the
saloutos 0:083111ae2a11 66 * stack.
saloutos 0:083111ae2a11 67 *
saloutos 0:083111ae2a11 68 * @note: This class is lazily initialized on first use.
saloutos 0:083111ae2a11 69 * This class is a POD type so if it is not used it will
saloutos 0:083111ae2a11 70 * be garbage collected.
saloutos 0:083111ae2a11 71 * @ingroup platform
saloutos 0:083111ae2a11 72 */
saloutos 0:083111ae2a11 73 template <class T>
saloutos 0:083111ae2a11 74 struct SingletonPtr {
saloutos 0:083111ae2a11 75
saloutos 0:083111ae2a11 76 /** Get a pointer to the underlying singleton
saloutos 0:083111ae2a11 77 *
saloutos 0:083111ae2a11 78 * @returns
saloutos 0:083111ae2a11 79 * A pointer to the singleton
saloutos 0:083111ae2a11 80 */
saloutos 0:083111ae2a11 81 T* get() {
saloutos 0:083111ae2a11 82 if (NULL == _ptr) {
saloutos 0:083111ae2a11 83 singleton_lock();
saloutos 0:083111ae2a11 84 if (NULL == _ptr) {
saloutos 0:083111ae2a11 85 _ptr = new (_data) T();
saloutos 0:083111ae2a11 86 }
saloutos 0:083111ae2a11 87 singleton_unlock();
saloutos 0:083111ae2a11 88 }
saloutos 0:083111ae2a11 89 // _ptr was not zero initialized or was
saloutos 0:083111ae2a11 90 // corrupted if this assert is hit
saloutos 0:083111ae2a11 91 MBED_ASSERT(_ptr == (T *)&_data);
saloutos 0:083111ae2a11 92 return _ptr;
saloutos 0:083111ae2a11 93 }
saloutos 0:083111ae2a11 94
saloutos 0:083111ae2a11 95 /** Get a pointer to the underlying singleton
saloutos 0:083111ae2a11 96 *
saloutos 0:083111ae2a11 97 * @returns
saloutos 0:083111ae2a11 98 * A pointer to the singleton
saloutos 0:083111ae2a11 99 */
saloutos 0:083111ae2a11 100 T* operator->() {
saloutos 0:083111ae2a11 101 return get();
saloutos 0:083111ae2a11 102 }
saloutos 0:083111ae2a11 103
saloutos 0:083111ae2a11 104 // This is zero initialized when in global scope
saloutos 0:083111ae2a11 105 T *_ptr;
saloutos 0:083111ae2a11 106 // Force data to be 4 byte aligned
saloutos 0:083111ae2a11 107 uint32_t _data[(sizeof(T) + sizeof(uint32_t) - 1) / sizeof(uint32_t)];
saloutos 0:083111ae2a11 108 };
saloutos 0:083111ae2a11 109
saloutos 0:083111ae2a11 110 #endif
saloutos 0:083111ae2a11 111