Vipin Ranka / MGAS_GR_Peach

This is the final version of Mini Gateway for Automation and Security desgined for Renesas GR Peach Design Contest

Dependencies:   GR-PEACH_video GraphicsFramework HTTPServer R_BSP mbed-rpc mbed-rtos Socket lwip-eth lwip-sys lwip FATFileSystem

Fork of mbed-os-example-mbed5-blinky by mbed-os-examples

mbed-dev/platform/SingletonPtr.h@12:9a20164dcc47, 2017-01-11 (annotated)

Committer:
vipinranka
Date:
Wed Jan 11 11:41:30 2017 +0000
Revision:
12:9a20164dcc47
This is the final version MGAS Project for Renesas GR Peach Design Contest

Who changed what in which revision?

UserRevisionLine numberNew contents of line
vipinranka 12:9a20164dcc47 1
vipinranka 12:9a20164dcc47 2 /** \addtogroup platform */
vipinranka 12:9a20164dcc47 3 /** @{*/
vipinranka 12:9a20164dcc47 4 /* mbed Microcontroller Library
vipinranka 12:9a20164dcc47 5 * Copyright (c) 2006-2013 ARM Limited
vipinranka 12:9a20164dcc47 6 *
vipinranka 12:9a20164dcc47 7 * Licensed under the Apache License, Version 2.0 (the "License");
vipinranka 12:9a20164dcc47 8 * you may not use this file except in compliance with the License.
vipinranka 12:9a20164dcc47 9 * You may obtain a copy of the License at
vipinranka 12:9a20164dcc47 10 *
vipinranka 12:9a20164dcc47 11 * http://www.apache.org/licenses/LICENSE-2.0
vipinranka 12:9a20164dcc47 12 *
vipinranka 12:9a20164dcc47 13 * Unless required by applicable law or agreed to in writing, software
vipinranka 12:9a20164dcc47 14 * distributed under the License is distributed on an "AS IS" BASIS,
vipinranka 12:9a20164dcc47 15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
vipinranka 12:9a20164dcc47 16 * See the License for the specific language governing permissions and
vipinranka 12:9a20164dcc47 17 * limitations under the License.
vipinranka 12:9a20164dcc47 18 */
vipinranka 12:9a20164dcc47 19 #ifndef SINGLETONPTR_H
vipinranka 12:9a20164dcc47 20 #define SINGLETONPTR_H
vipinranka 12:9a20164dcc47 21
vipinranka 12:9a20164dcc47 22 #include <stdint.h>
vipinranka 12:9a20164dcc47 23 #include <new>
vipinranka 12:9a20164dcc47 24 #include "platform/mbed_assert.h"
vipinranka 12:9a20164dcc47 25 #ifdef MBED_CONF_RTOS_PRESENT
vipinranka 12:9a20164dcc47 26 #include "cmsis_os.h"
vipinranka 12:9a20164dcc47 27 #endif
vipinranka 12:9a20164dcc47 28
vipinranka 12:9a20164dcc47 29 #ifdef MBED_CONF_RTOS_PRESENT
vipinranka 12:9a20164dcc47 30 extern osMutexId singleton_mutex_id;
vipinranka 12:9a20164dcc47 31 #endif
vipinranka 12:9a20164dcc47 32
vipinranka 12:9a20164dcc47 33 /** Lock the singleton mutex
vipinranka 12:9a20164dcc47 34 *
vipinranka 12:9a20164dcc47 35 * This function is typically used to provide
vipinranka 12:9a20164dcc47 36 * exclusive access when initializing a
vipinranka 12:9a20164dcc47 37 * global object.
vipinranka 12:9a20164dcc47 38 */
vipinranka 12:9a20164dcc47 39 inline static void singleton_lock(void)
vipinranka 12:9a20164dcc47 40 {
vipinranka 12:9a20164dcc47 41 #ifdef MBED_CONF_RTOS_PRESENT
vipinranka 12:9a20164dcc47 42 osMutexWait(singleton_mutex_id, osWaitForever);
vipinranka 12:9a20164dcc47 43 #endif
vipinranka 12:9a20164dcc47 44 }
vipinranka 12:9a20164dcc47 45
vipinranka 12:9a20164dcc47 46 /** Unlock the singleton mutex
vipinranka 12:9a20164dcc47 47 *
vipinranka 12:9a20164dcc47 48 * This function is typically used to provide
vipinranka 12:9a20164dcc47 49 * exclusive access when initializing a
vipinranka 12:9a20164dcc47 50 * global object.
vipinranka 12:9a20164dcc47 51 */
vipinranka 12:9a20164dcc47 52 inline static void singleton_unlock(void)
vipinranka 12:9a20164dcc47 53 {
vipinranka 12:9a20164dcc47 54 #ifdef MBED_CONF_RTOS_PRESENT
vipinranka 12:9a20164dcc47 55 osMutexRelease (singleton_mutex_id);
vipinranka 12:9a20164dcc47 56 #endif
vipinranka 12:9a20164dcc47 57 }
vipinranka 12:9a20164dcc47 58
vipinranka 12:9a20164dcc47 59 /** Utility class for creating an using a singleton
vipinranka 12:9a20164dcc47 60 *
vipinranka 12:9a20164dcc47 61 * @Note Synchronization level: Thread safe
vipinranka 12:9a20164dcc47 62 *
vipinranka 12:9a20164dcc47 63 * @Note: This class must only be used in a static context -
vipinranka 12:9a20164dcc47 64 * this class must never be allocated or created on the
vipinranka 12:9a20164dcc47 65 * stack.
vipinranka 12:9a20164dcc47 66 *
vipinranka 12:9a20164dcc47 67 * @Note: This class is lazily initialized on first use.
vipinranka 12:9a20164dcc47 68 * This class is a POD type so if it is not used it will
vipinranka 12:9a20164dcc47 69 * be garbage collected.
vipinranka 12:9a20164dcc47 70 */
vipinranka 12:9a20164dcc47 71 template <class T>
vipinranka 12:9a20164dcc47 72 struct SingletonPtr {
vipinranka 12:9a20164dcc47 73
vipinranka 12:9a20164dcc47 74 /** Get a pointer to the underlying singleton
vipinranka 12:9a20164dcc47 75 *
vipinranka 12:9a20164dcc47 76 * @returns
vipinranka 12:9a20164dcc47 77 * A pointer to the singleton
vipinranka 12:9a20164dcc47 78 */
vipinranka 12:9a20164dcc47 79 T* get() {
vipinranka 12:9a20164dcc47 80 if (NULL == _ptr) {
vipinranka 12:9a20164dcc47 81 singleton_lock();
vipinranka 12:9a20164dcc47 82 if (NULL == _ptr) {
vipinranka 12:9a20164dcc47 83 _ptr = new (_data) T();
vipinranka 12:9a20164dcc47 84 }
vipinranka 12:9a20164dcc47 85 singleton_unlock();
vipinranka 12:9a20164dcc47 86 }
vipinranka 12:9a20164dcc47 87 // _ptr was not zero initialized or was
vipinranka 12:9a20164dcc47 88 // corrupted if this assert is hit
vipinranka 12:9a20164dcc47 89 MBED_ASSERT(_ptr == (T *)&_data);
vipinranka 12:9a20164dcc47 90 return _ptr;
vipinranka 12:9a20164dcc47 91 }
vipinranka 12:9a20164dcc47 92
vipinranka 12:9a20164dcc47 93 /** Get a pointer to the underlying singleton
vipinranka 12:9a20164dcc47 94 *
vipinranka 12:9a20164dcc47 95 * @returns
vipinranka 12:9a20164dcc47 96 * A pointer to the singleton
vipinranka 12:9a20164dcc47 97 */
vipinranka 12:9a20164dcc47 98 T* operator->() {
vipinranka 12:9a20164dcc47 99 return get();
vipinranka 12:9a20164dcc47 100 }
vipinranka 12:9a20164dcc47 101
vipinranka 12:9a20164dcc47 102 // This is zero initialized when in global scope
vipinranka 12:9a20164dcc47 103 T *_ptr;
vipinranka 12:9a20164dcc47 104 // Force data to be 4 byte aligned
vipinranka 12:9a20164dcc47 105 uint32_t _data[(sizeof(T) + sizeof(uint32_t) - 1) / sizeof(uint32_t)];
vipinranka 12:9a20164dcc47 106 };
vipinranka 12:9a20164dcc47 107
vipinranka 12:9a20164dcc47 108 #endif
vipinranka 12:9a20164dcc47 109
vipinranka 12:9a20164dcc47 110 /** @}*/