36 lines
695 B
C
36 lines
695 B
C
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#pragma once
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#include "foundation/atomics.h"
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#include "lfitem.h"
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/* This data structure holds one item, and returns you the old item when you replace it
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it's sort of a "stack of 1" */
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template <class value_t>
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class LockFreeItem
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{
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public:
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typedef value_t *ptr_t;
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LockFreeItem()
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{
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lfitem_init(&item);
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}
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value_t *GetItem()
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{
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return (value_t *)lfitem_get(&item);
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}
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// returns the previous value
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value_t *SetItem(value_t *new_item)
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{
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return (value_t *)lfitem_set(&item, new_item);
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}
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// if there's already a value, returns what you passed in
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value_t *SetItemIfZero(value_t *new_item)
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{
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return (value_t *)lfitem_set_if_zero(&item, new_item);
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}
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lfitem_value_t item;
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};
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