2015-10-25 03:30:15 +00:00
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#include "mbed.h"
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#include "MicroBit.h"
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2015-10-25 15:30:05 +00:00
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void RefCounted::init()
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{
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// Initialize to one reference (lowest bit set to 1)
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refCount = 3;
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}
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static inline bool isReadOnlyInline(RefCounted *t)
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{
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uint32_t refCount = t->refCount;
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if (refCount == 0xffff)
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return true; // object in flash
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// Do some sanity checking while we're here
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if (refCount == 1)
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2015-10-25 19:59:45 +00:00
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uBit.panic(MICROBIT_USE_AFTER_FREE); // object should have been deleted
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2015-10-25 15:30:05 +00:00
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if ((refCount & 1) == 0)
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2015-10-25 19:59:45 +00:00
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uBit.panic(MICROBIT_REF_COUNT_CORRUPTION); // refCount doesn't look right
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2015-10-25 15:30:05 +00:00
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// Not read only
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return false;
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}
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bool RefCounted::isReadOnly()
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{
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return isReadOnlyInline(this);
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}
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2015-10-25 03:30:15 +00:00
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void RefCounted::incr()
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{
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2015-10-25 15:30:05 +00:00
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if (!isReadOnlyInline(this))
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refCount += 2;
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2015-10-25 03:30:15 +00:00
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}
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void RefCounted::decr()
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{
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2015-10-25 15:30:05 +00:00
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if (isReadOnlyInline(this))
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2015-10-25 03:30:15 +00:00
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return;
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2015-10-25 15:30:05 +00:00
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refCount -= 2;
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2015-10-27 15:19:56 +00:00
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if (refCount == 1) {
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2015-10-25 15:30:05 +00:00
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free(this);
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2015-10-25 03:30:15 +00:00
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}
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}
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