AxibugEmuOnline/AxibugEmuOnline.Client/Assets/Plugins/AxiReplay/InternalRingbuffer.cs

using System.Threading;

namespace AxiReplay
{
    public partial class FrameProfiler
    {
        internal class RingBuffer<T>
        {
            private readonly T[] buffer;
            private readonly int capacity;
            private int writePos;
            private int readPos;
            private int count;

            public RingBuffer(int capacity)
            {
                this.capacity = capacity;
                this.buffer = new T[capacity];
                this.writePos = 0;
                this.readPos = 0;
                this.count = 0;
            }

            public void Write(T item)
            {
                int localWritePos;
                int localReadPos;

                do
                {
                    localWritePos = Volatile.Read(ref writePos);
                    localReadPos = Volatile.Read(ref readPos);

                    int nextWritePos = (localWritePos + 1) % capacity;

                    if (nextWritePos == localReadPos)
                    {
                        // 缓冲区已满，覆盖最旧的未读数据
                        Interlocked.CompareExchange(ref readPos, (localReadPos + 1) % capacity, localReadPos);
                    }
                }
                while (Interlocked.CompareExchange(ref writePos, (localWritePos + 1) % capacity, localWritePos) != localWritePos);

                buffer[localWritePos] = item;
                Interlocked.Increment(ref count);
            }

            public bool TryRead(out T item)
            {
                item = default(T);

                int localReadPos;
                int localWritePos;

                do
                {
                    localReadPos = Volatile.Read(ref readPos);
                    localWritePos = Volatile.Read(ref writePos);

                    if (localReadPos == localWritePos)
                    {
                        return false; // 缓冲区为空
                    }
                }
                while (Interlocked.CompareExchange(ref readPos, (localReadPos + 1) % capacity, localReadPos) != localReadPos);

                item = buffer[localReadPos];
                Interlocked.Decrement(ref count);
                return true;
            }

            public int Available()
            {
                return Volatile.Read(ref count);
            }
        }
    }
}