util_buffer.c

来自「用CC2430的P1端口P1_0和P1_1实现对简单程序的测试！」· C语言 代码 · 共 182 行

/***********************************************************************************
  Filename:     util_buffer.c

  Description:  Ringbuffer implementation.

***********************************************************************************/

/***********************************************************************************
* INCLUDES
*/
#include "util_buffer.h"
#include "hal_board.h"
#include "hal_int.h"

/***********************************************************************************
* GLOBAL FUNCTIONS
*/

/***********************************************************************************
* @fn      bufInit
*
* @brief   Initialise a ringbuffer. The buffer must be allocated by the
*          application.
*
* @param   pBuf - pointer to the ringbuffer
*
* @return  none
*/
void bufInit(ringBuf_t *pBuf)
{
    uint16 s;

    // Critical section start
    s = halIntLock();

    pBuf->nBytes= 0;
    pBuf->iHead= 0;
    pBuf->iTail= 0;

    // Critical section end
    halIntUnlock(s);
}


/***********************************************************************************
* @fn      bufPut
*
* @brief   Add bytes to the buffer.
*
* @param   pBuf - pointer to the ringbuffer
*          pData - pointer to data to be appended to the buffer
*          nBytes - number of bytes
*
* @return  Number of bytes copied to the buffer
*/
uint8 bufPut(ringBuf_t *pBuf, const uint8 *pData, uint8 nBytes)
{
    uint8 i;
    uint16 s;

    // Critical section start
    s = halIntLock();

    i= 0;
    while(i<nBytes) {
        pBuf->pData[pBuf->iTail]= pData[i];
        pBuf->iTail++;
        if (pBuf->iTail==BUF_SIZE)
            pBuf->iTail= 0;
        i++;
    }
    pBuf->nBytes+= i;

    // Critical section end
    halIntUnlock(s);

    return i;
}


/***********************************************************************************
* @fn      bufGet
*
* @brief   Extract bytes from the buffer.
*
* @param   pBuf   - pointer to the ringbuffer
*          pData  - pointer to data to be extracted
*          nBytes - number of bytes
*
* @return  Bytes actually returned
*/
uint8 bufGet(ringBuf_t *pBuf, uint8 *pData, uint8 nBytes)
{
    uint8 i;
    uint16 s;

    // Critical section start
    s = halIntLock();

    i= 0;
    while(i<nBytes && i<pBuf->nBytes) {
        pData[i]= pBuf->pData[pBuf->iHead];
        pBuf->iHead++;
        if (pBuf->iHead==BUF_SIZE)
            pBuf->iHead= 0;
        i++;
    }
    pBuf->nBytes-= i;

    // Critical section end
    halIntUnlock(s);
    return i;
}


/***********************************************************************************
* @fn      bufPeek
*
* @brief   Read bytes from the buffer but leave them in the queue.
*
* @param   pBuf   - pointer to the ringbuffer
*          pData  - pointer to data to be extracted
*          nBytes - number of bytes
*
* @return  Bytes actually returned
*/
uint8 bufPeek(ringBuf_t *pBuf, uint8 *pData, uint8 nBytes)
{
    uint8 i,j;
    uint16 s;

    // Critical section start
    s = halIntLock();

    i= 0;
    j= pBuf->iHead;
    while(i<nBytes && i<pBuf->nBytes) {
        pData[i]= pBuf->pData[j];
        j++;
        if (j==BUF_SIZE)
            j= 0;
        i++;
    }

    // Critical section end
    halIntUnlock(s);
    return i;
}


/***********************************************************************************
* @fn      bufNumBytes
*
* @brief   Return the byte count for the ring buffer.
*
* @param   pBuf- pointer to the buffer
*
* @return  Number of bytes present.
*/
uint8 bufNumBytes(ringBuf_t *pBuf)
{
    return pBuf->nBytes;
}

/***********************************************************************************
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  Software unless you agree to abide by the terms of the License. The License
  limits your use, and you acknowledge, that the Software may not be modified,
  copied or distributed unless embedded on a Texas Instruments microcontroller
  or used solely and exclusively in conjunction with a Texas Instruments radio
  frequency transceiver, which is integrated into your product.  Other than for
  the foregoing purpose, you may not use, reproduce, copy, prepare derivative
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  YOU FURTHER ACKNOWLEDGE AND AGREE THAT THE SOFTWARE AND DOCUMENTATION ARE
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