X-NUCLEO-MEMS1 function call constructs

[Mario Simunic]

Hi,

Here is the code from CubeMX generated BSP module for hts221 sensor.

/**
  * @brief  Read generic device register
  *
  * @param  hts221_ctx_t* ctx: read / write interface definitions
  * @param  uint8_t reg: register to read
  * @param  uint8_t* data: pointer to buffer that store the data read
  * @param  uint16_t len: number of consecutive register to read
  *
  */
int32_t hts221_read_reg(hts221_ctx_t *ctx, uint8_t reg, uint8_t *data,
                        uint16_t len)
{
  int32_t ret;
  ret = ctx->read_reg(ctx->handle, reg, data, len);
  return ret;
}

I need help to understand constructs like in this code. int32_t hts221_read_reg(hts221_ctx_t *ctx, uint8_t reg, uint8_t *data, uint16_t len) is function which is doing something with a pointers, but I'm not sure what.

And Why? What are benefits of such a constructs. Is it mandatory to use it because of some coding standard (ie. MISRA-C ) or is it something else?

Thanks.

[Tesla DeLorean]

It is calling a function pointer providing the underlying support functions.

I think this allows for a) abstraction, b) different busing, c) multiple sensors