Ping Pong Buffer 双缓冲 C++代码学习

typedef struct
    {
        void *buffer[2];
        volatile uint8_t writeIndex;
        volatile uint8_t readIndex;
        volatile uint8_t readAvaliable[2];
    } PingPongBuffer_t;

void *buffer[2] 无类型指针，指向不同数据类型的缓冲Buff

volatile uint8_t writeIndex 缓冲写索引

volatile uint8_t readIndex 缓冲读索引

volatile uint8_t readAvaliable[2] 可读标志位

void PingPongBuffer_Init(PingPongBuffer_t *ppbuf, void *buf0, void *buf1)
{
    memset(ppbuf, 0, sizeof(PingPongBuffer_t));
    ppbuf->buffer[0] = buf0;
    ppbuf->buffer[1] = buf1;
}


bool PingPongBuffer_GetReadBuf(PingPongBuffer_t *ppbuf, void **pReadBuf)
{
    if (ppbuf->readAvaliable[0])
    {
        ppbuf->readIndex = 0;
    }
    else if (ppbuf->readAvaliable[1])
    {
        ppbuf->readIndex = 1;
    }
    else
    {
        return false;
    }
    *pReadBuf = ppbuf->buffer[ppbuf->readIndex];
    return true;
}


void PingPongBuffer_SetReadDone(PingPongBuffer_t *ppbuf)
{
    ppbuf->readAvaliable[ppbuf->readIndex] = false;
}


void PingPongBuffer_GetWriteBuf(PingPongBuffer_t *ppbuf, void **pWriteBuf)
{
    if (ppbuf->writeIndex == ppbuf->readIndex)
    {
        ppbuf->writeIndex = !ppbuf->readIndex;
    }
    *pWriteBuf = ppbuf->buffer[ppbuf->writeIndex];
}


void PingPongBuffer_SetWriteDone(PingPongBuffer_t *ppbuf)
{
    ppbuf->readAvaliable[ppbuf->writeIndex] = true;
    ppbuf->writeIndex = !ppbuf->writeIndex;
}