Eddystone test using modified DAL

Dependencies:   BLE_API mbed-dev-bin nRF51822

Dependents:   microbit-eddystone

Fork of microbit-dal by Lancaster University

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Show/hide line numbers RefCounted.cpp Source File

RefCounted.cpp

00001 /*
00002 The MIT License (MIT)
00003 
00004 Copyright (c) 2016 British Broadcasting Corporation.
00005 This software is provided by Lancaster University by arrangement with the BBC.
00006 
00007 Permission is hereby granted, free of charge, to any person obtaining a
00008 copy of this software and associated documentation files (the "Software"),
00009 to deal in the Software without restriction, including without limitation
00010 the rights to use, copy, modify, merge, publish, distribute, sublicense,
00011 and/or sell copies of the Software, and to permit persons to whom the
00012 Software is furnished to do so, subject to the following conditions:
00013 
00014 The above copyright notice and this permission notice shall be included in
00015 all copies or substantial portions of the Software.
00016 
00017 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00018 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00019 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
00020 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00021 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
00022 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
00023 DEALINGS IN THE SOFTWARE.
00024 */
00025 
00026 /**
00027   * Base class for payload for ref-counted objects. Used by ManagedString and MicroBitImage.
00028   * There is no constructor, as this struct is typically malloc()ed.
00029   */
00030 #include "mbed.h"
00031 #include "MicroBitConfig.h"
00032 #include "RefCounted.h"
00033 #include "MicroBitDisplay.h"
00034 
00035 /**
00036   * Initializes for one outstanding reference.
00037   */
00038 void RefCounted::init()
00039 {
00040     // Initialize to one reference (lowest bit set to 1)
00041     refCount = 3;
00042 }
00043 
00044 /**
00045   * Checks if the object resides in flash memory.
00046   *
00047   * @param t the object to check.
00048   *
00049   * @return true if the object resides in flash memory, false otherwise.
00050   */
00051 static inline bool isReadOnlyInline(RefCounted *t)
00052 {
00053     uint32_t refCount = t->refCount;
00054 
00055     if (refCount == 0xffff)
00056         return true; // object in flash
00057 
00058     // Do some sanity checking while we're here
00059     if (refCount == 1 ||        // object should have been deleted
00060         (refCount & 1) == 0)    // refCount doesn't look right
00061         microbit_panic(MICROBIT_HEAP_ERROR);
00062 
00063     // Not read only
00064     return false;
00065 }
00066 
00067 /**
00068   * Checks if the object resides in flash memory.
00069   *
00070   * @return true if the object resides in flash memory, false otherwise.
00071   */
00072 bool RefCounted::isReadOnly()
00073 {
00074     return isReadOnlyInline(this);
00075 }
00076 
00077 /**
00078   * Increment reference count.
00079   */
00080 void RefCounted::incr()
00081 {
00082     if (!isReadOnlyInline(this))
00083         refCount += 2;
00084 }
00085 
00086 /**
00087   * Decrement reference count.
00088   */
00089 void RefCounted::decr()
00090 {
00091     if (isReadOnlyInline(this))
00092         return;
00093 
00094     refCount -= 2;
00095     if (refCount == 1) {
00096         free(this);
00097     }
00098 }