37 lines
953 B
C
37 lines
953 B
C
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#pragma once
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#include <atomic>
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// A simple queue. No locks, but only works with a single thread as producer and a single thread as
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// a consumer. Mutex up as needed.
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template <typename ElementType, size_t QueueSize>
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class MsgQueue {
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ElementType queue_[QueueSize];
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std::atomic_uint nextAdd_{0};
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std::atomic_uint nextSend_{0};
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std::atomic_uint pendingSends_{0};
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public:
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MsgQueue() {}
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ElementType* GetNextAddMessage()
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{
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// if we are falling behind, bail
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if (pendingSends_.load() >= QueueSize) {
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return nullptr;
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}
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auto index = (nextAdd_++) % QueueSize;
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return &queue_[index];
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}
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void CommitAdd() { ++pendingSends_; }
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bool HavePendingSends() const { return pendingSends_.load() != 0; }
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ElementType* GetNextSendMessage()
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{
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auto index = (nextSend_++) % QueueSize;
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return &queue_[index];
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}
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void CommitSend() { --pendingSends_; }
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};
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